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And so far, all the gear I’ve seen has been rather well-balanced in terms of advantages and drawbacks, meaning that overpowered god-builds feel unlikely, and creative stat-juggling should be quite the fun challenge. However, for those who’ve been waiting five years for another hunter x hunter web game adventure, I don’t think x hunter online will be good enough. An ancient robot who devoted his life to give birth to his children?
If you’re in the mood for a more competitive battle, x hunter game’s “hunter x game” player-versus-player (PvP) mode, much like the battlegrounds in hunter x hunter game online, pits two teams against one another in a battle to the death. But hunter x hunter games has a loot system. hxh game involves gathering piles of loot, something which is addictive for veteran RPG gamers.The portable screen magnifies small details that are lost when the console is docked.
 Be prepared to play the hunter x game beyond the first main ending; that’s simply the end of the first part, and the full Hunter X Online plays out over five different endings. Canonically strong team combinations.Though Nintendo’s limits on full Excel-spreadsheet nerdery may be a shortcoming in the eyes of those who revel in such systems, if the idea of an RPG is to role-play then shouldn’t I be able to slay the final boss if I, the player, role-playing as the hero, am skilled enough? It’s odd that hunter x hunter browser game and now Zelda champion such outside-the-box thinking when it ought to be role-playing hunter x hunter mmorpg games that consider such matters the most heavily. Because while the traditional – and less obvious – fighting hunter x hunter online game archetypes are present and correct, from all-rounder hunter x online game, to nimble, acrobatic hunter x hunter mmorpg online, to tricksy, technical, trap-setting Dr.
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Positional mutation is a protein engineering technique that substitutes, inserts or deletes specific nucleotides in known DNA sequences based on the known structure and function of proteins to produce mutant protein (enzyme) molecules with novel traits. The technology is widely used in the biological and medical fields. Position mutation technology has the characteristics of high mutation rate, simple and easy to perform, and good repeatability. As a research method, localization mutation technology is also widely used to study the relationship between protein structure and function, so as to elucidate the regulation mechanism of genes, the etiology and mechanism of diseases.

 

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Introduction

The "small change" of protein molecules based on natural protein structure refers to the modification, substitution or deletion of a few residues of proteins of known structure. This is the most widely used method in protein engineering, and can be mainly divided into proteins. Two types of modification and gene location mutation. Gene-localized mutation refers to the transformation of protein molecules at the genetic level, that is, the method of site-directed mutagenesis, the insertion, deletion, substitution and reorganization of nucleotide codons of genes encoding proteins, and then the mutated genes are carried out. The protein expresses and analyzes the functional activity of the expressed protein, and the result provides a new design for protein molecular engineering.

 

Design goals and solutions for location mutation

The common design goals of localization mutations are to improve the heat and acid stability of proteins, increase activity, reduce side effects, improve specificity, and conduct structural-functional studies through protein engineering. Hartley is equal to 1986 to complete a design goal and solution that we want, and still has important reference value. The stability of protein is an important prerequisite for the normal biological activity of proteins. Therefore, improving the stability of proteins has become one of the important goals of protein design and transformation.

 

Type of mutation

There are many ways to change the nucleotide sequence of a gene, such as chemical synthesis of genes, direct modification of genes, and cassette mutation technology. Depending on the manner in which the gene is mutated, it can also be classified into three categories: insertion of one or more amino acid residues; deletion of one or more amino acid residues; replacement or substitution of one or more amino acid residues. In order to achieve the purpose of gene location mutation, in vitro recombinant DNA technology or PCR method is often used.

 

Site-directed mutation

The amino acids in a protein are determined by the triplet codon in the gene. By changing one or two bases, the amino acid species can be changed to produce a new protein. It is usually the amino acid that changes a position in the functional region to study the structure, stability or catalytic properties of the protein. The work of point mutation is the main body of current protein engineering research. So far, many kinds of proteins such as subtilisin, T4 lysozyme, dihydrofolate reductase, trypsin and ribonuclease have been modified. For example, replacing Asn117 of a tissue-type plasminogen activator (t-PA) with Glu117, thereby removing an original glycosylation site; since the original sugar chain can promote t -PA is cleared from plasma, so point mutations can reduce plasma clearance of t-PA and prolong plasma half-life.

 

Box mutation

In 1985, Wells proposed a genetic modification technique for a box-type mutation that can produce 20 different amino acid mutants at one site, and can perform "saturation" analysis of important amino acids in protein molecules. Using the localization mutation, two original vectors and endonuclease cleavage points not present on the gene are added on both sides of the amino acid code to be modified, and the endonuclease is used to digest the gene, and then the synthesized double-stranded DNA fragment with different changes is substituted for digestion. part. A variety of mutant genes can be obtained in such a single treatment.

 

Procedure for locating mutations

The protein molecular design program for gene localization mutation follows the procedure in the design principle, but the gene location mutation has its own particularity, and its specific procedure is as follows.

  1. Establish a structural model of the protein under study

Establishing a three-dimensional structural model of a protein is critical to establishing a mutation site or region and predicting the structure and function of the mutated protein. The structure can be determined by X-ray crystallography, two-dimensional nuclear magnetic resonance, or the like, or a structural model can be established based on the structure of the analog or other structural prediction methods.

  1. Identify locations that have a significant impact on the required properties
  2. Predict the structure of the mutant
  3. Construct mutants. Mutant protein
  4. Examination of mutant proteins

 

About us

We provide custom protein services in the biological sciences, enabling access to the latest tools, techniques, and expertise with competitive pricing and rapid turnaround time. We serve a broad spectrum of industrial and academic clients with a commitment to delivering high-quality data and customer services. Here are some our products: SPR, Co-Immunoprecipitation, Pull-Downs, CLIP-seq, etc.

qxcvbnmy

Positional mutation is a protein engineering technique that substitutes, inserts or deletes specific nucleotides in known DNA sequences based on the known structure and function of proteins to produce mutant protein (enzyme) molecules with novel traits. The technology is widely used in the biological and medical fields. Position mutation technology has the characteristics of high mutation rate, simple and easy to perform, and good repeatability. As a research method, localization mutation technology is also widely used to study the relationship between protein structure and function, so as to elucidate the regulation mechanism of genes, the etiology and mechanism of diseases.

 

%E5%9B%BE%E7%89%872-300x123.png

 

Introduction

The "small change" of protein molecules based on natural protein structure refers to the modification, substitution or deletion of a few residues of proteins of known structure. This is the most widely used method in protein engineering, and can be mainly divided into proteins. Two types of modification and gene location mutation. Gene-localized mutation refers to the transformation of protein molecules at the genetic level, that is, the method of site-directed mutagenesis, the insertion, deletion, substitution and reorganization of nucleotide codons of genes encoding proteins, and then the mutated genes are carried out. The protein expresses and analyzes the functional activity of the expressed protein, and the result provides a new design for protein molecular engineering.

 

Design goals and solutions for location mutation

The common design goals of localization mutations are to improve the heat and acid stability of proteins, increase activity, reduce side effects, improve specificity, and conduct structural-functional studies through protein engineering. Hartley is equal to 1986 to complete a design goal and solution that we want, and still has important reference value. The stability of protein is an important prerequisite for the normal biological activity of proteins. Therefore, improving the stability of proteins has become one of the important goals of protein design and transformation.

 

Type of mutation

There are many ways to change the nucleotide sequence of a gene, such as chemical synthesis of genes, direct modification of genes, and cassette mutation technology. Depending on the manner in which the gene is mutated, it can also be classified into three categories: insertion of one or more amino acid residues; deletion of one or more amino acid residues; replacement or substitution of one or more amino acid residues. In order to achieve the purpose of gene location mutation, in vitro recombinant DNA technology or PCR method is often used.

 

Site-directed mutation

The amino acids in a protein are determined by the triplet codon in the gene. By changing one or two bases, the amino acid species can be changed to produce a new protein. It is usually the amino acid that changes a position in the functional region to study the structure, stability or catalytic properties of the protein. The work of point mutation is the main body of current protein engineering research. So far, many kinds of proteins such as subtilisin, T4 lysozyme, dihydrofolate reductase, trypsin and ribonuclease have been modified. For example, replacing Asn117 of a tissue-type plasminogen activator (t-PA) with Glu117, thereby removing an original glycosylation site; since the original sugar chain can promote t -PA is cleared from plasma, so point mutations can reduce plasma clearance of t-PA and prolong plasma half-life.

 

Box mutation

In 1985, Wells proposed a genetic modification technique for a box-type mutation that can produce 20 different amino acid mutants at one site, and can perform "saturation" analysis of important amino acids in protein molecules. Using the localization mutation, two original vectors and endonuclease cleavage points not present on the gene are added on both sides of the amino acid code to be modified, and the endonuclease is used to digest the gene, and then the synthesized double-stranded DNA fragment with different changes is substituted for digestion. part. A variety of mutant genes can be obtained in such a single treatment.

 

Procedure for locating mutations

The protein molecular design program for gene localization mutation follows the procedure in the design principle, but the gene location mutation has its own particularity, and its specific procedure is as follows.

  1. Establish a structural model of the protein under study

Establishing a three-dimensional structural model of a protein is critical to establishing a mutation site or region and predicting the structure and function of the mutated protein. The structure can be determined by X-ray crystallography, two-dimensional nuclear magnetic resonance, or the like, or a structural model can be established based on the structure of the analog or other structural prediction methods.

  1. Identify locations that have a significant impact on the required properties
  2. Predict the structure of the mutant
  3. Construct mutants. Mutant protein
  4. Examination of mutant proteins

 

About us

We provide custom protein services in the biological sciences, enabling access to the latest tools, techniques, and expertise with competitive pricing and rapid turnaround time. We serve a broad spectrum of industrial and academic clients with a commitment to delivering high-quality data and customer services. Here are some our products: SPR, Co-Immunoprecipitation, Pull-Downs, CLIP-seq, etc.

qxcvbnmy

The genetic engineering was established in the early 1970s and it has played an important role in the field of biology after decades of continuous progress and development.

Plant genetic engineering technology uses recombinant DNA technology to systematically transform and recombine biological genes by artificial "shearing" and "splicing" in vitro, and then insert and integrate into the recipient plant genome to reorganize. The gene is expressed in the recipient cell, so that the recipient plant obtains a new shape and breeds a new variety with high yield, multi-resistance and high quality.

The research and application of plant genetic engineering is flourishing around the world and is considered to be the hope of agriculture in the 21st century. It plays an important role in the new agricultural revolution.

1. Plant genetic engineering and its technologies

Based on human's goals and design, plant genetic engineering was conducted through split, integrate, splice, etc. in vitro to make the genetic material is recombined, and those features are then transferred to the plant through a specific vector (such as plasmid, phage, virus, etc.) intracellularly, and the expression of the required genes are expressed in cells. With this, a new plant type is created. Genetic engineering has a superior development space for improving plant traits, quality, increasing yield, and improving plant resistance to diseases, insects, and stress resistance. Therefore, its future development is extremely broad.

Plant engineering genetic technology has greatly expanded the gene pool available to plants, and it has become a reality to initiate directional mutation according to people's preset plans, which has brought huge changes in plant breeding (mainly in the following aspects: break reproductive isolation, making it creates conditions for broadening the available gene banks of plants, and providing new techniques for manipulating mutations; most of the genes used for genetic engineering breeding have been studied more clearly. The purpose of improving plants is clear, and the selection means is effective, so that it is possible to produce directional variation and directional selection; by improving some key traits of plants, the original promotion varieties will be improved to a large extent, not only can shorten the breeding period, but also make a comprehensive breakthrough in different ecological regions; with the deepening of understanding of genetic engineering, the cloning of new genes and the improvement of transgenic technology, and the targeted operation of multiple genes will also be possible, which is difficult to imagine in conventional breeding, and may lead to new "green" Revolution").

2. The possible risk and mechanism of genetically engineered plants

People have gradually realized that because the current level of science and technology can not accurately predict all the manifestations of plant genetic engineering, the safety of plant genetic engineering has attracted people's attention.

2.1. Possible risk of genetic engineering plants

(1) The threat of genetically engineered plants to environmental safety:

The effect of insect-resistant genetically engineered plants on other organisms. The insecticidal effect of insect-resistant genetically engineered plants is non-selective. It can also kill beneficial insects or other organisms in the environment while killing pests. Even when their residues are degraded in the soil, they will also affect insects or microorganisms in the soil.

Antiviral genetically engineered plants pose a risk of new viruses. At present, in genetic engineering of antiviral plants, most of the genes introduced into plants are sequences derived from the viral genome, and the most widely used are CP gene, MP gene and replicase gene.

The potential threat of genetically engineered plants to the Earth's ecosystem. After the release of genetically engineered plants, gene drift is inevitable, which causes the transferred genes to be passed on to other crops. Metabolites of genetically engineered plants will spread to the external environment, causing a chain reaction.

(2) The harm of genetically engineered plants to human health:

Genetically engineered plants may contain known or unknown toxins that are toxic to humans.

Genetically engineered plants may contain known or unknown allergens, causing allergic reactions in the human body and even death.

Genetically engineered plants produce certain nutrients or nutritional qualities that cause certain symptoms in the body.

After the genetically engineered plant is eaten by humans, the food will pass the drug resistance gene to the pathogenic bacteria in the human body, which will make the body resistant.

2.2 The mechanism of genetic engineering plant to cause risk

(1). Genetic engineering causes mutations in DNA in plants. Genetic engineering introduces foreign genes into plant gene tissues, causing DNA mutations in plants. Different locations of foreign gene introduction may lead to changes in plant gene expression, enzyme expression, or in unknown growth and metabolism in plants, which may produce or polymerize certain harmful substances, thereby threatening human health.

(2). Genetic engineering causes plants to contain new proteins that directly or indirectly endanger human health. Plant genetic engineering introduces genetic information into plants, and this genetic information may come from any organism on the earth that allows plants to produce new proteins. This new protein may directly harm human health or this new protein affects plant cell metabolism and changes the nutrient composition of the plant, thereby affecting human health.

(3). The harm may be caused by the unpredictability of genetic engineering. Although DNA can be spliced very accurately under laboratory conditions, the effect of a foreign gene into a plant on the entire plant genome cannot be fully predicted and controlled. The plant is an extremely complex living system, and our existing scientific knowledge and technical means cannot fully control the inheritance of plants.

3. Suggestions on improving the safety management of plant genetic engineering

(1). Have a full understand on the strategic significance of genetic engineering safety management, and improve the safety awareness of genetic engineering of all people, especially leading cadres and related scientific research and staff, and popularize relevant laws and regulations on genetic engineering safety management.

(2). Formulate a comprehensive "Genetic Engineering Law" to ensure that all laws and regulations on the safety management of genetic engineering are available.

(3). Establish an effective and timely genetic engineering supervision and reporting system, and conduct long-term follow-up monitoring of projects with higher risk levels to ensure that genetic engineering safety is within the controllable range.

(4). Establish a scientific genetic engineering risk assessment mechanism and explore the establishment of an authoritative genetic engineering risk assessment social organization. Strengthen the approval of research, development, promotion, import and export, and extend the review time of high-risk projects.

With the rapid development of plant genetic engineering technology, the emergence of new gene introduction technology (such as CRISPR/CAS9, TALEN-Mediated DNA Insertion, Virus-induced Gene Silencing etc.)and the technology of crop tissue culture are more convenient and effective. In the near future, it is expected to produce high-yield, high-quality, high-efficiency, disease-resistant, insect-resistant and anti-adversity crops. A new crop variety with excellent traits will benefit human beings and become an important weapon for human beings to understand nature and transform nature. At the same time, when seeing the achievements of genetic engineering plant, we must also see the risk of genetically modified plants.

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Protein is mainly composed of chemical elements such as carbon, hydrogen, oxygen and nitrogen. It is an important biological macromolecule. All proteins are multimers formed by the connection of 20 different amino acids. After Forming proteins, these amino acids are also called as a residue.

 

The boundaries between proteins and peptides are not very clear. Some people believe that the number of residues required for a functionally acting domain is called a polypeptide or peptide if the number of residues is less than 40. To function biologically, proteins need to be properly folded into a specific configuration, mainly through a large number of non-covalent interactions (such as hydrogen bonds, ionic bonds, van der Waals forces and hydrophobic interactions); in addition, in some proteins (especially in the case of secreted proteins), disulfide bonds also play a key role. In order to understand the mechanism of action of proteins at the molecular level, it is often necessary to determine the three-dimensional structure of a protein. Structural biology has been developed by studying protein structure, using techniques including X-ray crystallography, nuclear magnetic resonance, etc. to resolve protein structures.

 

A certain number of residues are necessary to exert a certain biochemical function; 40-50 residues are usually the lower limit of the size of a functional domain. Protein size can range from such a lower limit up to thousands of residues. The current estimated average length of proteins differs between different species, typically about 200-380 residues, while eukaryotes have an average protein length of about 55% longer than prokaryotes. Larger protein aggregates can be formed by many protein subunits; for example, by the polymerization of thousands of actin molecules to form protein fibers.

 

Discovery history

In 1959, Perutz and Kendrew analyzed the structure of hemoglobin and myoglobin, solved the three-dimensional structure, and won the 1962 Nobel Prize in Chemistry.

Pauling discovered the basic structure of the protein. Based on the X-ray diffraction data, Crick and Watson proposed a model of the three-dimensional structure of DNA. Received the 1962 Nobel Prize in Physiology or Medicine. After the 1950s, Hauptmann and Karle established a purely mathematical theory for the direct determination of crystal structures using X-ray analysis, which has epoch-making significance in crystal research, especially in the study of macromolecular biological substances such as hormones, antibiotics, and proteins. And the molecular structure of new drugs played an important role. They were awarded the 1985 Nobel Prize in Chemistry.

 

Structure type

Protein molecules are covalent polypeptide chains formed by the condensation of amino acids end-to-end, but natural protein molecules are not loose random polypeptide chains. Each natural protein has its own unique spatial structure or three-dimensional structure, which is often referred to as the conformation of the protein, ie the structure of the protein.

The molecular structure of a protein can be divided into four levels to describe its different aspects:

Primary structure: A linear amino acid sequence that makes up a protein polypeptide chain.

Secondary structure: a stable structure formed by hydrogen bonds between C=O and N-H groups between different amino acids, mainly α-helix and β-sheet.

Tertiary structure: The three-dimensional structure of a protein molecule formed by the arrangement of multiple secondary structural elements in three dimensions.

Quaternary structure: used to describe a protein complex molecule that is functionally formed by interactions between different polypeptide chains (subunits).

In addition to these structural levels, proteins can be transformed in multiple similar structures to perform their biological functions. For functional structural changes, these tertiary or quaternary structures are usually described in a chemical conformation, and the corresponding structural transformation is referred to as a conformational change.

 

 

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Adjuvant Selection is the main method for finding molecular genetic markers, vaccines like bacterial vaccines, cancer vaccines, RNA vaccines, MAS breeding and so on.

Major methods for finding molecular genetic markers

DNA markers are divided into two types: type markers, mainly are some single genes, and used to compare the homologous loci varieties of relative distance and chain and linear correlation; type markers, mainly high polymorphism, information content rich DNA fragments, is one of the most commonly used microsatellite marker. Through Adjuvant Optimization, more and more kinds of molecular markers were introduced, including restricted fragment length polymorphism (RFLP), random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), and Microsatellites. At present, there are 2,505 markers in the world's pig research, including 1,391 microsatellite markers. type 873, type mark 1632.

The main methods to search for molecular genetic markers are candidate gene method and genome scanning method.

1. Candidate gene method as a candidate gene for a trait, it is usually some genes whose biological functions and nucleic acid sequences are known, and they are involved in the growth and development process of the trait. These genes may be structural genes, regulatory genes or genes that affect the expression of traits in biochemical metabolic pathways. Candidate gene method research should follow certain steps, such as candidate gene selection primer design, gene specific fragment amplification, polymorphic locus search and so on. Candidate gene search USES genes that are thought to have a direct physiological function for a trait to find QTLS. In addition, genes found in other species that control some traits can be studied as candidate genes for pigs. For example, the h-fabp gene affects the backfat thickness and intramuscular fat content of pigs (Gerbens et al., 1999). 2000; 2001); The melanocorticoid receptor 4 (MC4R) gene was significantly correlated with the intake, backfat thickness and growth rate of pigs (Kim et al., 1999; 2000).

2. Genome scanning: all genetic information is stored on the 19 pairs of chromosomes of the pig. Reference families were established, such as meishan European and American pig species, wild boar big white pig, and their hybrid offspring were used to find QTL through genetic markers. The most effective design is the genotype analysis of F2 generation isolation population. Figure 4-2 is a simple schematic diagram of single genetic marker and linkage QTL analysis. Alleles of genetic markers and their linkage QTL in F1 generation were heterozygous. In the F2 generation isolation population, the ratio of the three possible genotypes per seat should be 1:2:1, when the average performance of marker genotypes is compared, the existence of linkage QTL can be analyzed.

Anderson (1994), such as reported with a wild boar by the results of the large white building reference group, using the 105 DNA markers in the genetic map, the separation of F2 generation 200 pigs linkage analysis research found that on chromosome 4 seat back fat and control the growth rate, the average genetic effect 24 g/d and 5 mm, respectively, the equivalent of F2 DaiQun total phenotypic variation of 12% and 18%. Daily weight gain can differ by more than 50g between two extreme homozygous genotypes, resulting in a 10kg weight difference at market time in pigs.

(iii) MAS breeding

In pig breeding selection, it is difficult to determine the sex efficiency of low heritability (e.g., reproductive traits), high cost of measurement (e.g., disease resistance), phenotypic values (e.g., lean meat rate) or limited sexual performance (e.g., milk production) early in development. It is estimated that the selection of the marker before the determination of the offspring can increase the selectivity response by 10%~15%. The MAS of compatriots who choose to combine can be increased by about 40%. Combining multiple genetic markers and trait information, the selectivity response can be increased by 50%~200%. Using marker selection in cross breeding can predict and make full use of heterosis. Molecular genetic markers can also be applied to early selection and screening and detection of large populations to select populations with desired genotypes.

For example, there is little progress in the improvement of pig litter, a low genetic trait, by traditional methods. Rothschild et al. found in 1994 that the estrogen receptor (ESR) gene was one of the main genes responsible for the litter size of pigs, which could control the total litter size of 1.5 pigs and the live litter size of 1 pig in the meishan synthetic line of China. In the Chinese two-flower face hybrid population, the agricultural university of China not only confirmed the results of Rothschild et al., but also found another main gene locus controlling the number of piglets - FSH, which can control the total number of piglets and the number of live piglets by 2.0.

Although MAS can improve the effectiveness of selection and the annual amount of genetic improvement, its effectiveness is also affected by many factors. In addition to the heritability of traits, the intensity of selection, and the size of the selected population, the determinants are the linkage between genetic markers and QTLS. Zhang (1992) pointed out that each QTL could be specifically detected by using genetic markers closely linked to QTL, and the final selection of genetic markers would be equivalent to the selection of QTL itself. Therefore, genetic markers closely related to QTL must be obtained in order to improve MAS efficiency. Resources at present, through the establishment of the pig family, has some related to the growth, reproduction and carcass, meat quality of QTL mapping in some microsatellite nearby, such as on chromosome 3 microsatellite Sw2427 - Sw251 area and daily gain of pigs, on chromosome 4 S0101 - S0107 area and back fat belly fat, 7 chromosome S0064 S0066 regional composition and has a strong correlation between birth weight and body. It can be predicted that with the discovery of more genetic markers closely linked to QTL, MAS will be applied more effectively in practical breeding.

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3 Cancer vaccine adjuvant selection

The initial aim of formulating vaccines in adjuvants was to deliver the antigen in a poorly metabolizing and slowly degrading substance. The intention was to favor the slow and sustained release of the antigen to be captured by antigen-presenting cells (APCs) and be subsequently presented to T cells. Aluminum salts are widely used to favor T helper cell 2 (Th2)-mediated humoral immunity, but they are less efficient for promoting Th1-dependent immunity. To this aim, water-in-oil adjuvants have been developed to create a depot of the antigen at the site of the injection. The next generation of vaccine delivery agents includes nanoparticles such as silica or liposomes or synthetic polymers, which are ideal vehicles to be taken up by dendritic cells (DCs) patrolling within the subcutaneous tissues. However, the challenge with such supports is to selectively promote DC uptake while eluding the systemic reticuloendothelial network of macrophages, which routinely clear circulating particles. In addition to these substances designed to favor delivery of the antigen to APCs, today’s therapeutic vaccines also contain another class of adjuvants aimed to deliver danger signals to activate the immune system, as antigen alone may fail to prime effective T cell responses or even induce tolerance.

4 The choice of cancer vaccine delivery system

The choice of delivery systems and route of immunization depends on the end use of the vaccine. For practical reasons and minimal side effects, most prophylactic vaccines are administered via the skin, usually by subcutaneous injections in the epidermis or the dermis. These two locations are ideal, as they are enriched respectively in Langerhans DCs and dermal DCs, both cell populations being very efficient in capturing and processing antigens. The oral route is also very convenient and is used by vaccines against polio, typhoid fever, cholera, and rotavirus. The oral route is, however, more challenging in view of the extreme conditions in the gastrointestinal tract, including the low pH in the stomach and the presence of microbiota, which may degrade the antigen before it reaches the lymphoid organs. Moreover, the usually tolerogenic gut environment may not be ideal to generate a strong systemic immune response.

With regard to therapeutic vaccines used to treat chronic noncontagious diseases such as cancer, atopy, or diabetes, both immediate cellular effector responses and long-term immunity are desired to guarantee the continuous immune-surveillance of the disease. Although prophylactic vaccines for global immunization programs must be simple, inexpensive, and given via a noninvasive route, therapeutic cancer vaccines can benefit from more complicated technologies and use more invasive routes of delivery if beneficial for the patient. There is a very large array of cancer vaccines under development which use various delivery systems, and which are being tested in clinical trials. Other delivery routes tested in therapeutic cancer vaccines range from subcutaneous and intradermal to more invasive intraperitoneal and intranodal injections, to optimize antigen uptake by APCs and favor a local potent immune response. For instance, particulate therapeutic vaccines such as virosomes or nanoparticles can be injected in LNs using an ultrasound-guided imaging procedure. Although most of these strategies are still in the development stage, the potential to achieve strong and long-lasting antitumor responses is high, owing to new delivery systems and better understanding of T cell memory development.

Reference

[1] FUTURE II Study Group. Quadrivalent vaccine against HumanPapillomavirns to prevent high-grade cervical lessions. N Engl J Med, 2007, 356(19): 1915

[2] Olsson SE, Villa LL, Costa RLR, et a1. Induction of inmmne memory following administration of a prophylactic quadrivalent human papillomavirus (HPV) types 6/1 1/16/18 LI virus-like particle (VLP) vaccine. Vaccine, 2007 (25): 4931

[3] Harris JE, Ryan L, Hoover Jr HC, et a1. Adjuvant active specific immunotherapy for stage II and III colon cancer with an autologous tumor cell vaccine: Eastern Cooperative Oncology Group Study E5283. J Clin Orwol, 2000, 18(1): 148

[4] Berd D, Maguire Jr HC, Mastrangelo MJ, et a1. Treatment of human melanoma with a hapten — modified antologous vaccine. Ann NY Acad Sci, 1993, 690(8): 7

[5] Remann R, Goldschmidt AJ, Richter A. Adjuvant therapy of renal cell carcinoma patients with an autologous tumor cell lysate vaccine: a-year—follow—up analysis AnticancerRes, 2003, 23(2A): 969

[6] Mitchell MS, Kan — Mitchell J, Kempf RA, et a1. Active specific im-munotherapy for melanoma: phase I trial of allogeneic lysates and a novel adjuvant. Cancer Res, 1988, 48(20): 5883

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3 Benign Mucous Membrane Pemphigoid

3.1 Clinical manifestations

  Conjunctival and oral mucosal damage accounted for 60% to 90%, patients with nasal, pharyngeal, genital and anal mucosa accounted for about 25%, skin involvement is rare, skin damage is very similar to the lesions of bullous pemphigoid, but the time is short, and the stenosis or adhesion caused by scar healing and scar formation is characteristic.

3.1.1 Eye damage

The eye is the only affected part, and the damage usually occurs asymmetrically. After 1 to 2 years, the contralateral eye mucosa is involved. There are symptoms of catarrhal conjunctivitis. Transparent blisters can be found and quickly ruptured. Subsequently, scar atrophy, conjunctival and bulbar conjunctiva adhesions, eye movement involvement, tendon varus leading to secondary corneal changes, corneal opacity, scar formation of the tarsal plate with mucosa, atrophy of the gland and blockage of the lacrimal duct, thus corneal dryness, discoloration and blinding ulcers are formed.

3.1.2 Mucosal damage

Multiple blisters quickly form painful erosions and the scars heal. If the damage occurs in the tongue ligament, the contracted scar can limit the movement of the tongue. Damage that occurs in soft palate, tonsil, and buccal mucosa may limit food intake. The genital area of the vulva can form a head adhesion, a vaginal stenosis, and the like.

3.1.3 Skin damage

The incidence of skin damage is only about 25%, the damage is a tension blisters, the blister wall is not easy to rupture, occurs on erythematous skin, one or more parts. Healed with atrophic scars. If bullae occur in the head, scarring hair loss may occur. Generalized lesions are extremely rare, and even if there are secondary scar formation.

Benign mucosal pemphigoid can occur repeatedly for several years without significant effect on general health. The faster the disease progresses, the worse the prognosis. Due to eating difficulties, malnutrition and cachexia may occur, and the incidence of blindness is approximately 20% to 60%. Although extremely rare, there have been reports of cancerous changes in the scars of the oral mucosa.

3.2 Laboratory examination

3.2.1Histopathology: typical epidermis blister, no spine release. Infiltration of inflammatory cells composed of lymphocytes, plasma cells, and eosinophils can be seen in the upper dermis. Subsequently, there were a large number of fibroblasts with superficial dermal fibrosis and vascular hyperplasia and scar contracture.

3.2.2 Immunofluorescence: direct immunofluorescence of skin mucosa to detect IgG and C3 deposition in the basement membrane zone, and IgA and C3 deposition were also observed. The homogenous linear deposition was almost the same as that in bullous pemphigoid. The positive rate of indirect immunofluorescence detection of anti-basal membrane circulating antibodies was <10%, and the titer was low. If the DIF is negative, the fresh tissue should be removed from the erythema around the lesion for repeated testing.

4 Pathogenesis of Pemphigus

In the plasma of patients with pemphigus, there is anti-Dsg3 and/or anti-Dsg1 IgG, and no anti-Dsg2 antibody exists. This autoreactive antibody binds to its corresponding antigen, leading to a series of clinical pemphigus. The emergence of performance. In the active phase of pemphigus vulgaris, the serum is mainly pathogenic IgG4 subclass and IgG1, while in the serum of patients with long-term remission, there are low-valency IgG1 subclasses, IgG4 and Dsg1 and Dsg13 on keratinocytes. The combination causes the loss of adhesion between cells, leading to the release of intercellular cells and the formation of blisters in the epidermis.

The antigen Dsg produced in the MMP autoimmune disease belongs to the transmembrane component of desmos, belonging to the cadherin superfamily in the adhesion molecule, whose gene is located at 18q12.1. Dsg is divided into three categories: Dsg1, Dsg2, and Dsg3. Among them, Dsg2 is expressed in all tissues with desmosome, including monolayer epithelial cells and myocardial tissue. Dsg1 and Dsg3 are mainly restricted to stratified squamous cells. Current studies have shown that Dsg1 and Dsg3 are target antigens of pemphigus foliaceus (PF) and pemphigus vulgaris (PV), respectively. The relative molecular mass of Dsg3 is about 130 kD. which is mainly distributed on the surface of keratinocytes in the basal layer of the epidermis and the upper layer of the basal layer. The relative molecular mass of Dsg1 is about 160 kD, which is mainly distributed on the keratinocyte membrane in the upper layer of the epidermis, with the advantage of granular layer and subgranular layer expression. The Dsg3 and Dsg1 molecules, like other cadherin molecules, have five tandem repeats of approximately equal size extracellular domain (EC), each of which is approximately 100 amino acid residues in length, of which EC1 the region corresponds to the extracellular amino terminal residue and EC5 is at the carboxy terminus. The difference between Dsg1 and Dsg3 is mainly due to the homology of the 1 to 4 extracellular domains of Dsg1 and the homology of the 5 extracellular domains of Dsg3. Unlike classical cadherins, Dsg1 has a longer intracellular fragment, and the extracellular fragment of Dsg3 is slightly longer than Dsg1, but its intracellular domain is slightly shorter and has no glycine/serine-rich region.

In the five extracellular domains of the pemphigus antigen, EC1, EC2, and EC4 have relatively large homology and can be specifically recognized by the plasma of pemphigus patients. Therefore, these epitopes are called "an immune-dominant epitope, or a "pathogenic epitope," an antibody that specifically recognizes an epitope is called a "pathogenic antibody." The pemphigus antigen contains at least one "pathogenic epitope" in the EC1 -2 region, and antibodies against EC1 -2 are closely related to the pathogenesis of pemphigus. The recombinant protein expressed by the EC1 -2 and EC3 -4 gene sequences of Dsg3 only reacted with the plasma of pemphigus patients, and the response rates of the two were 57.9 % and 52.6%, respectively, and the bullous pemphigoid, system Lupus erythematosus and normal people do not respond. This indicates that EC1 -2 and EC3 -4 are antigen-specific and have a high affinity with pemphigus antibodies, thus providing a new approach for serological diagnosis and identification of pemphigus.

In Dsg1 and Dsg3, when either function is lost, the other can partially compensate for its function. This theory explains the tissue specificity of the loss of intercellular adhesion caused by autoantibodies in pemphigus patients. Because Dsg1 and Dsg3 have a certain distribution pattern, the difference in anti-Dsg antibodies also leads to differences in the clinical manifestations of pemphigus. By inserting the Dsg1 gene into Dsg3 knockout mice to form a transgenic mouse capable of expressing Dsg1, it was found that Dsg1 can compensate for partial Dsg3-mediated loss of intercellular adhesion function, which is confirmed genetically.

5 Treatment

Glucocorticoid is preferred for the treatment of pemphigus. Most scholars at home and abroad are empirical drugs. There are ethnic and regional differences in the choice of hormone dose. At present, the severity of the disease is not unified by using the scoring system. If the two are linked to the hormone dose and applied to the clinic, the treatment plan will be more reasonable. Determine the initial dose of hormone according to the ABSIS system: ABSIS skin severity score 10, give 30 ~ 40 mg / d, skin score of 10 ~ 50, 60 mg / d is appropriate, skin score > 50 points, give 80 mg /d. If the skin lesions are not controlled for 5 to 7 days, increase the dose by 50%. Reduced indications: Daily new blistering number <5, no new erythema; no obvious exudation of erosion surface; pemphigus antibody titer decreased earlier; ABSIS skin score decreased by more than 35%.

The long-term use of large doses of hormones can easily lead to many drug reactions. Therefore, the combination of immunosuppressive agents, including azathioprine, cyclophosphamide, mycophenolate mofetil, etc., is generally used to reduce the number of hormones and shorten the treatment time. At the same time, it can be combined with an immune-modulator (Amlalazine, etc.), plasma exchange method and in vitro. Photochemotherapy, etc. Randomized controlled observation of prednisone combined with mycophenolate mofetil, azathioprine and prednisone alone in the treatment of 42 cases of pemphigus, combined with the ABSIS system to assess the severity of the disease before and after treatment, the results show that the three treatment days The short-term efficacy and safety of acne are similar, but prednisone combined with mycophenolate mofetil reduces the dose of hormones most significantly. In recent years, some biological agents and treatments have become new choices for the treatment of pemphigus, such as rituximab, high-dose intravenous immunoglobulin (IVIG), immunosorbent assay, TNF-α antagonist and hematopoietic stem cell transplantation therapy.

 For the severe bullous disease such as pemphigus, detecting the Dsg ELISA index has certain guiding significance for judging its severity. However, if medical workers are to accurately grasp the changes in their condition, they also rely on an effective and widely recognized scoring system to provide a reliable clinical basis for the treatment and adjustment of pemphigus. At present, there are few clinical applications of ABSIS and PDAI. Both have their own advantages and disadvantages. If they can be combined, it is expected to improve the evaluation method. The correlation between the disease scoring system and antibody levels, and the number of hormones controlled by scoring will be important research topics. Many new drugs and treatments have emerged in recent years, and multi-center large-scale clinical trials are still needed to explore the best treatment options.

 

Reference

[1] Barnadas MA, Rubiales MV, Gich I, et al. Usefulness of specific anti-desmoglein 1 and 3 enzyme-linked immunoassay and indirect immunofluorescence in the evaluation of pemphigus activity [J]. Int J Dermatol, 2015, 54(11): 1261-1268.

[2] Daneshpazhooh M, Kamyab K, Kalantari MS, et al. Comparison of desmoglein 1 and 3 enzyme - linked immunosorbent assay and direct immunofluorescence for evaluation of immunological remission in pemphigus vulgaris [J]. Clinical & Experimental Dermatology, 2014, 39(1): 41-47.

[3] Nakahara T, Takagi A, Yamagami J, et al. High anti-desmoglein 3 antibody ELISA index and negative indirect immunofluorescence result in a patient with pemphigus vulgaris in remission: evaluation of the antibody profile by newly developed methods [J]. Jama Dermatology, 2014, 150(12): 1327-1330.

[4] Pfutze M, Niedermeier A, Eming R. Introducing a novel autoimmune bullous skin disorder intensity score ( ABSIS) in pemphigus [J]. Eur J Dermatol, 2007, 17(1): 4-11.

[5] Murrell DF, Dick S, Amagai M, et al. Consensus statement on definitions of disease, end points, and therapeutic response for pemphigus [J]. J Am Acad Dermatol, 2008, 58(6): 1043-1046.

[7] Chams-Davatchi C, Rahbar Z, Daneshpazhooh M, et al. Pemphigus vulgaris activity score and assessment of convergent validity [J]. Acta Med Iran, 2013, 51(51): 224-230.

[8] Sebaratnam DF, Frew JW, Davatchi F, et al. Quality -of-Life Measurement in Blistering Diseases [J]. Dermatol Clin, 2012, 30(2): 301-307.

[9] Mahajan VK, Sharma NL, Sharma RC, et al. Twelve-year clinicotherapeutic experience in pemphigus: a retrospective study of 54 cases [J]. Int J Dermatol, 2005, 44(10): 821-827.

[10] Agarwal M, Walia R, Kochhar AM, et al. Pemphigus Area and Activity Score (PAAS) --a novel clinical scoring method for monitoring of pemphigus vulgaris patients [J]. Int J Dermatol, 1998, 37(2): 158-160.

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What is 3D cell culture?

Three-dimensional cell culture is based on the common three-dimensional culture model of the scaffold, which can better simulate the natural environment in which the cells grow. Three-dimensional cell culture (TDCC) refers to the co-culture of vectors with different materials in three dimensions and various kinds of cells in vitro, so that cells can migrate and grow in the three-dimensional spatial structure of the carrier. Three-dimensional cell-carrier complex.

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Frontier knowledge about 3D cell culture research

  1. Three-dimensional cell tissue plus tensile culture model of the United States flexcell company Tissue Train tensile stress stimulation three-dimensional hydrogel stent cell tissue culture system.

Functional highlights of the three-dimensional cell tissue augmentation culture model: after burning three-dimensional cell tissue culture and stretching three-dimensional cell tissue culture in the true sense of three-dimensional culture - the system with a variety of coated surfaces (Amino, Collagen (Type I Or IV), Elastin, ProNectin (RGD), Laminin (YIGSR) collagen hydrogels for extracellular matrix scaffolds in biomaterial scaffold studies, compared to traditional nanofiber scaffolds and porous scaffolds, hydrogel scaffolds The network contains a lot of water, which can supply cell nutrients well, and can also cross-link bioactive factors to regulate cell growth and differentiation. Therefore, hydrogel scaffolds can better simulate the tissue-like physics required for cell growth. The spatial structure has high plasticity, relatively simple manufacturing process and convenient clinical application.

  1. Three-dimensional cell tissue pressure-carrying culture system model of American three-dimensional cell tissue after-force culture model

Three-dimensional cell culture in three-dimensional cell culture

1) The system provides periodic or static pressure loading of various tissue, three-dimensional cell cultures;

2) based on the deformation of the flexible film substrate, uniform force;

3) Real-time observation of the reaction of cells and tissues under pressure;

4) can selectively block stress loading on cells;

5) Simultaneously have multi-channel cell pull force loading function;

6) Up to 4 channels, 4 different programs can be run simultaneously, and multiple different pressure deformation rate comparison experiments are performed;

7) Multiple frequencies (0.01-5 Hz), multiple amplitudes and multiple waveforms can be operated in the same program;

8) Better control of waveforms under ultra-low or ultra-high stress;

9) A variety of waveform types: static waveform, positive rotation waveform, cardiac waveform, triangular waveform, rectangle and various special waveforms;

10) computer system for pressure loading cycle, size, frequency, duration precise intelligent control typical application range: detection Biochemical reactions of various tissues and cells under pressure.

  1. Three-dimensional cell tissue augmentation culture model. Three-dimensional cell tissue stretchestensile force loading culture system model of American flexcell company Three-dimensional cell culture three-dimensional cell tension loading culture

1) The system provides axial and circumferential stress loading on two-dimensional, three-dimensional cells and tissues;

2) based on the deformation of the flexible film substrate, uniform force;

3) The reaction of cells and tissues under stress can be observed in real time;

4) can selectively block stress loading on cells;

5) Simultaneous multi-channel cell pressure loading function;

6) In combination with the Flex Flow parallel slab flow chamber, fluid shear stress can be applied while pulling the cells;

7) Up to 4 channels, 4 different programs can be run simultaneously, and multiple different tensile deformation rate comparison experiments are performed;

8) Multiple frequencies, multiple amplitudes and multiple waveforms can be operated in the same program;

9) Better control of waveforms under ultra-low or ultra-high stress;

10) Multiple waveform types: static waveform, positive rotation waveform, cardiac waveform, triangular waveform, rectangle, and various special waveforms;

3 Three-dimensional cell cultures in life applications:

Customized 3D cell culture services are common in our lives, and there are also 3D cell culture related products on the market.

  • Creative Bioarrayoffers 35 human cell systems with over 160 different cell types. Moreover, we also provide our customers primary cells from over 13 types of other animals.
  • These cells taken from living tissue are extremely accurate as they are literally coming from the source and are available from many sources on the human body. These living samples can give extremely accurate information about the cells in vivo and give relevant information regarding the living systems.
  • Not only canCreative Bioarray offer such a wide range of primary cells of humans, but we also have a selection of primary cells of animals for comparative testing.

Bone cells, which are found within the bone tissue, are responsible for bone production, maintenance and modeling. There are three different types of cells that found only in the bone. The osteoblasts are derived from mesenchymal stem cells and its function is bone matrix synthesis and its subsequent mineralization. The osteoclasts are large cells that dissolve the bone and osteocytes are cells inside the bone. At Creative Bioarray, we offer 6 types of human primary bone cells including: Human Bone marrow-derived endothelial Cells, Human Osteoblast Cells, Human Osteoblasts (HOB), Human Osteoblast Cells (Postnatal), Human Calvarial Osteoblasts (HCO) and Human Osteoblasts-femural (HO-f). The method we use to isolate endothelial cells was developed based on a combination of established and our proprietary methods. These cells are pre-coated with PECAM-1 antibody, following the application of magnetic beads pre-coated with secondary antibody. Human osteoblasts may be used for various types of in vitro, in vivo, or regenerative medicine studies in normal or diseased systems. In addition, they may be used in bone development studies.

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Many people regard designer brand for their footwear as the only way to go and businesses that offer those brands tend to get patronized more often. Wholesale shoes and boots is the way for retail businesses to go to take advantage of the latest fashion trends on the market at discounted prices. Even for those who have a liberal spending budget for their business and gets the styles that they want when they first come out, let's face it, that getting a discount on the quality that shows off business sense, good taste, and stylish sensitivity leaves more money in your pocket for other needs such as more inventory or bonuses to employees for exceeding sales quotas.

There are those who believe that what you put on your feet can make or break the entire look of a clothing choice and in part, there is some truth to this. Poorly fitting shoes or those that are worn with the heel lifts wearing out can make a brand new suit look dingy. With wholesale boots or wholesale shoes, especially designer names that people readily recognize, a retailer can give people the option to create a perfectly polished look that speaks volumes about taste, style, and fashion sense, and no one has to know that the designer boots or shoes did not cost the full price; including the customer making the purchase.

A wide variety of wholesalers offer great choices in wholesale shoes and boots, and not just designer names, for those who do not have to have a brand name label on their feet to reflect their personal fashion sense. A properly fitted shoe or boot is essential to foot comfort, whether it is for a busy day at work or a dazzling night out on the town. Getting stylish and trendy bargain wholesale shoes in flats, platforms, stacked heels, clogs or whatever style is desired, is the ticket to avoiding paying a fortune to resell footwear to the public with a handsome profit for your business.

Whether your business is attempting to appeal to those with a shoe fetish or just has a reputation for providing the public with a variety of shoes to choose from, wholesale shoes are fantastic choices. Many wholesalers provide instant access to the wholesale boots and shoes market and make it possible take advantage of great prices whether for low quantities or high volume stocking up. When it comes to designer quality, some big names have remained constant over the years, and at the same time the introduction of newcomers to the industry has broadened the selection and made it possible for retailers who swear by designer selections to help their customers stay outfitted from head to toe in their ideal choices.

Getting wholesale boots and wholesale shoes, whether design or everyday style, can be the ticket to providing customers with the luxury and comfort their feet deserve in every season. Whether the quest is for women, men or children's selections, a little due diligence can put these discounted designer brands and others right at the ready for those who want to have a big name in their footwear selections on the premises, but don't want to have to spend a fortune to get them. Wholesale shoes and boots in designer varieties are the sensible way to stay trendy and maintain your establishment's spending budget at the same time.

 

View More: Wholesale Shoes China 

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Neutron scattering research at the Department of Energy's Oak Ridge National Laboratory has revealed clear structural differences in the normal and pathological forms of a protein involved in Huntington's disease.

Huntington's disease, an incurable neurodegenerative disorder, starts as a genetic mutation that leads to an overabundance of "huntingtin" protein fragments, which form clumps in the brain.

Valerie Berthelier of the University of Tennessee Graduate School of Medicine, who co-led the study published in Biophysical Journalwith ORNL's Chris Stanley, said the goal was to establish a baseline understanding of huntingtin's structure in order to eventually determine the true structural basis of Huntington's disease.

"This is a very first step -- the hope is that we do this basic research to shed light on the structures of the protein," Berthelier said. "If we can start identifying any of these structures as toxic or potentially toxic, and then think about how drugs could interact with them, then we might be getting to the point of rationally designing therapeutics that would target those specific structures."

The researchers conducted a side-by-side study of model protein systems in solution using a time-resolved small-angle neutron scattering technique at ORNL's High Flux Isotope Reactor. The use of neutrons, a non-damaging but highly penetrating particle, allowed the team to study the biological materials over time without degrading the samples' structural integrity.

"We compared the normal and disease versions of the protein to see how they change over time," Stanley said. "You can see there's a discrepancy all the way from the early stages to the end-state fibrils."

The study's results showed key differences in the ways mutant and normal huntingtin proteins take shape. The disease protein, for instance, initially forms aggregates of one to two peptides, whereas the normal version makes bigger aggregates, gathering seven or eight peptides together.

These data on the very early stages of protein aggregate formation support a growing focus of the research in the amyloid field. Amyloid disorders, such as Parkinson's, Alzheimer's and Huntington's, all involve protein aggregation phenomena leading to a disease.

"There is no strong correlation between neuronal cell loss and the amount of protein aggregates found in the brain," Stanley said. "You could have a case with a lot of aggregates but minimal symptoms -- and you can find the converse. Researchers think there must be something happening at the earliest stage that's giving rise to toxicity."

Stanley says the team hopes to continue its research to obtain higher-resolution structural data and refine their understanding of the huntingtin protein.

"We'd like to use this small-angle neutron scattering technique in combination with others to get a better idea for how these early structures are forming and also ask the question -- are they toxic or not?" Stanley said.

The research is published as "Investigating the Structural Impact of the Glutamine Repeat in Huntingtin Assembly." Coauthors are Helen McWilliams-Koeppen, Erica Rowe and Tatiana Perevozchikova.

Related Tags:Protein Structure, Electron Microscope, VLP Construction 

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Overworked and stressed out? Look on the bright side. Some stress is good for you.

"You always think about stress as a really bad thing, but it's not," said Daniela Kaufer, associate professor of integrative biology at the University of California, Berkeley. "Some amounts of stress are good to push you just to the level of optimal alertness, behavioral and cognitive performance."

New research by Kaufer and UC Berkeley post-doctoral fellow Elizabeth Kirby has uncovered exactly how acute stress -- short-lived, not chronic -- primes the brain for improved performance.

In studies on rats, they found that significant, but brief stressful events caused stem cells in their brains to proliferate into new nerve cells that, when mature two weeks later, improved the rats' mental performance.

"I think intermittent stressful events are probably what keeps the brain more alert, and you perform better when you are alert," she said.

Kaufer, Kirby and their colleagues in UC Berkeley's Helen Wills Neuroscience Institute describe their results in a paper published April 16 in the new open access online journal eLife.

The UC Berkeley researchers' findings, "in general, reinforce the notion that stress hormones help an animal adapt -- after all, remembering the place where something stressful happened is beneficial to deal with future situations in the same place," said Bruce McEwen, head of the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology at The Rockefeller University, who was not involved in the study.

Kaufer is especially interested in how both acute and chronic stress affect memory, and since the brain's hippocampus is critical to memory, she and her colleagues focused on the effects of stress on neural stem cells in the hippocampus of the adult rat brain. Neural stem cells are a sort of generic or progenitor brain cell that, depending on chemical triggers, can mature into neurons, astrocytes or other cells in the brain. The dentate gyrus of the hippocampus is one of only two areas in the brain that generate new brain cells in adults, and is highly sensitive to glucocorticoid stress hormones, Kaufer said.

Much research has demonstrated that chronic stress elevates levels of glucocorticoid stress hormones, which suppresses the production of new neurons in the hippocampus, impairing memory. This is in addition to the effect that chronically elevated levels of stress hormones have on the entire body, such as increasing the risk of chronic obesity, heart disease and depression.

Less is known about the effects of acute stress, Kaufer said, and studies have been conflicting.

To clear up the confusion, Kirby subjected rats to what, to them, is acute but short-lived stress -- immobilization in their cages for a few hours. This led to stress hormone (corticosterone) levels as high as those from chronic stress, though for only a few hours. The stress doubled the proliferation of new brain cells in the hippocampus, specifically in the dorsal dentate gyrus.

Kirby discovered that the stressed rats performed better on a memory test two weeks after the stressful event, but not two days after the event. Using special cell labeling techniques, the researchers established that the new nerve cells triggered by the acute stress were the same ones involved in learning new tasks two weeks later.

"In terms of survival, the nerve cell proliferation doesn't help you immediately after the stress, because it takes time for the cells to become mature, functioning neurons," Kaufer said. "But in the natural environment, where acute stress happens on a regular basis, it will keep the animal more alert, more attuned to the environment and to what actually is a threat or not a threat."

They also found that nerve cell proliferation after acute stress was triggered by the release of a protein, fibroblast growth factor 2 (FGF2), by astrocytes -- brain cells formerly thought of as support cells, but that now appear to play a more critical role in regulating neurons.

"The FGF2 involvement is interesting, because FGF2 deficiency is associated with depressive-like behaviors in animals and is linked to depression in humans," McEwen said.

Kaufer noted that exposure to acute, intense stress can sometimes be harmful, leading, for example, to post-traumatic stress disorder. Further research could help to identify the factors that determine whether a response to stress is good or bad.

"I think the ultimate message is an optimistic one," she concluded. "Stress can be something that makes you better, but it is a question of how much, how long and how you interpret or perceive it."

The eLife paper was coauthored by UC Berkeley colleagues Sandra E Muroy, Wayne G. Sun and David Covarrubias of the Department of Molecular and Cell Biology; Megan J. Leong of the Helen Wills Neuroscience Institute; and Laurel A. Barchas of the Department of Integrative Biology. Kirby is now a post-doctoral fellow at Stanford University.

Kaufer's research was funded by a BRAINS (Biobehavioral Research Awards for Innovative New Scientists) award from the National Institute of Mental Health of the National Institutes of Health (R01 MH087495) and the National Alliance for Research on Schizophrenia and Depression. Kirby was supported by fellowships from the California Institute for Regenerative Medicine and the U.S. Department of Defense.

Related Tags:FGFR4, FGF23, FGF2

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Often times in the summer you might lose your appetite or feel too full because of the heat. Or maybe you're running late in the morning and still need to eat breakfast. A quick and easy protein shake is a great way to get all the nutrients your body needs without feeling like you're stuffing yourself.

MYTH: Protein shakes are for bodybuilders and will make me bulky.

REALITY: If you read my last article about Toning Your Muscles, you now know that nobody becomes a bodybuilder by accident. Everybody's body needs protein and adding a supplement to ensure you get enough is only going to help in the effort to reshape your body.

MYTH: Protein shakes will make me fat.

REALITY: If you are eating too much and then you add in a protein shake on a regular basis, you may see some weight gain. In that case, use the shake to replace a meal or snack. If you're one of my clients, however, that is used to hearing from me "you're not eating enough!" this may be a good way to get some extra calories in.

MYTH: It's not healthy to eat too much protein.

REALITY: It's actually very difficult to eat so much protein that it has an adverse effect on your system if you're a healthy individual. The American College of Sports Medicine recommends every person eat 0.8x their body weight in kilograms of protein every day. For a 150lb person, this is about 68g protein every day. If you're concerned about your protein intake, consult your physician. If your physician expresses no concern then you're likely in the clear.

Making sure you get enough protein in your diet is essential if you want to change the shape of your body. One of my favorite analogies is protein as the bricks to build the house that is your body. This analogy is detailed in my article Dieting Fads and Why They Don't Work.

There are different kinds of whey protein powder that you can buy but be aware: a lot of them taste nasty! I've tried a lot of them and my some of favorites are Designer Whey, Pure Protein and Syntrax Nectar. Pure Protein you can actually find at Stop & Shop for $21 for a 2lb container. This should last you at least a month. You can click STORE on my website and then click Protein Powders to see what they look like or to order from Amazon. Whatever you decide to buy, make sure there is less than 5g of fat, carbs, and sugar, and more than 15g of protein per 1 scoop.

And finally, adding a protein shake is merely an idea if you're looking for something quick and easy to get your protein in. By no means do you HAVE to include it. You can get all the nutrients your body needs from "real" food.

Related Tags:Protein Expression, Bacillus Expression, Yeast Expression Systems 

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This article is intended to provide several analysis methods of a few important substances that they are well known. The first is bile acids analysis.

  

  Bile acid is an important component of bile and plays an important role in fat metabolism. Bile acid mainly exists in the intestinal and liver circulation system and acts as a protective role during recycling. Only a small amount of the bile acid enters the peripheral circulation.

 

  Bile acid analysis is of great importance to the research and development of clinical chemistry and bile acid drugs. As early as the ancient Chinese " Shennong's Herbal Classic " recorded the efficacy of carp gall. In addition, many important prescriptions, such as Bezoar powder and liushen pill, contain animal bile acids. Studies on bile acids in western countries began in the early 19th century, and quantitative studies began in the 1970s.

 

  The second is Catecholamines acids also known as pyrocatechol. Catecholamine is a neurotransmitter including catechins and amines. Catechins and amines are bound by an enzymatic process of l-tyrosine with sympathetic nerve, adrenal medulla and chromaffin cells. In general, catecholamine refers to norepinephrine (NA), adrenaline (Adr) and dopamine (DA). All three catecholamines are converted from tyrosine as precursors.

 

  As a neurotransmitter and hormone, catecholamine is closely related to people's health and disease. It is not only directly involved in behavioral activities or the regulation of neural functions such as blood pressure, heart rate, breathing and sleep, but also associated with some functional diseases such as schizophrenia and depression. Catecholamines Analysis began in the 1940s.With the deepening of the research on catecholamine, the analytical methods have been developing and improving all the time. At present, the research methods of molecular electrochemistry have become the leading one

 

  The third one is eicosanoids. Eicosanoids is a kind of bioactive unsaturated fatty acids, it is an important inflammatory factor, widely exists in body fluids and tissues, regulating many physiological and pathological processes. There are many kinds of eicosanoids in vivo, the content is low, and there are a lot of isomers. Therefore, the separation and analysis of eicosanoids in vivo are facing great challenges.

 

  As for eicosanoids analysis, Although there have been a lot of research on analytical methods, but still many problems waiting to solve. Neither extraction method has formed a standard extraction scheme for different biological samples. Therefore, the establishment of standardized extraction methods for different biological samples will greatly facilitate the eicosanoids analysis. The most powerful tool for analysis is the combination of chromatography-mass spectrometry. The characteristics of high sensitivity, high selectivity, high flux and high speed provide a good technical platform for the establishment of fast analytical methods. With the continuous development of various technologies, analytical methods will be continuously optimized and play a greater role in the research of biomarkers discovery, pathological mechanism and drug action mechanism.

 

  The last one is vitamins. There are two parts of vitamins analysis: water soluble vitamins analysis and fat soluble vitamins analysis.

 

  Vitamin is one of the important elements of human growth and development. At present, many foods are added with water-soluble vitamins, but there is a serious question whether they meet the requirements. Therefore, the development of research on it has certainly guiding significance for people's scientific intake and scientific control of the additive amount in food.

 

  Fat soluble vitamins are insoluble in water but soluble in fats and some organic solvents, including vitamin A, vitamin D, vitamin E and vitamin K. Fat soluble vitamins can be stored in large amounts in the body, mainly in the liver, so excessive intake will cause poisoning. Fat-soluble vitamins are becoming increasingly popular in clinical field. Thus, it is necessary to give reasonable attention to the analysis of the content and function of fat-soluble vitamins so that ensure the safety of use, maintain physical health.

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Fibroblast growth factor (FGFs) is a polypeptide composed of about 150-200 amino acids and exists in two closely related forms, namely, basic fibroblast growth factor (bFGF) and acidic fibroblast growth factor (aFGF). Its receptor (FGFR) belongs to the receptor protein tyrosine kinase, currently known FGFR mainly includes four types, FGFR1, FGFR2, FGFR3 and FGFR4. Clinically, FGFR overexpression and activation in tumor tissues are found to be associated with the occurrence of a variety of cancers, which can promote tumor angiogenesis and tumor cell proliferation. Therefore, FGFR is widely considered as an important drug target for anti-tumor, which has attracted extensive attention from pharmaceutical scientists in various countries.

In vitro experiments, both types of FGF stimulated the DNA synthesis of osteoblast-like cells isolated from rat cranial cap. Meanwhile, bFGF stimulated the colony formation of differentiated chondrocytes in AGAR, playing a role in mitogen and morphology. AFGF can be formed by macrophages, cartilage and chondrocytes, which can stimulate the proliferation of immature chondrocytes and their progenitors. In vivo studies, FGF has been observed to promote the repair of articular cartilage. The expression of FGF was also found in the mouse fracture model by immunohistochemistry.

In addition, fibroblast growth factor has the following main effects on the human body:

1. Effects on the skeletal system: It promotes the generation of a large number of osteoblasts and inhibits osteoclasts. To treat osteoporosis, femoral head necrosis, arthritis, rheumatism and diseases caused by calcium deficiency.

2. Effects on the digestive system: It can strengthen gastrointestinal function, promote the digestion of enzymes, increase appetite, treatment of chronic gastritis.

3. Effects on the blood system: It can strengthen the hematopoietic function of bone marrow, promote the generation of stem cells, and then generate a large number of red blood cells and white blood cells. Strengthening left ventricular thickness, enhancing myocardial elasticity, effectively treating heart disease. Effectively removing low density protein in the blood, preventing deposition in the blood vessel wall, and treating thrombosis.

Here are some important FGFs members and their main functions below:

1. FGF2

Fibroblast growth factor 2(FGF2), also called the basic fibroblast growth factor(bFGF), is widely involved in cell growth, differentiation, migration, angiogenesis and tumorigenesis. The FGF2 gene is located at 4q26 of human chromosome, the length of which is 38kb, contains 3 exons and 2 introns. The active FGF2 can be combined with the fibroblast growth factor receptor (FGFR) which has the nature of tyrosine kinase receptor (FGFR) through heparin sulfate proteoglycans (HSPG), activate PKC, Ras /Raf /MEK/ERK, P13K, JAK/STAT and other signaling pathways, and participate in the regulation of cell proliferation, differentiation and malignant transformation. In the cardiovascular system, studies have shown that FGF2 is involved in cardiac hypertrophy caused by stress load and angiotensin. However, some studies also have shown that FGF2 can cause cell chromatin concentration, inhibit proliferation and cause cell apoptosis. Clearly, the cardiovascular role of FGF2 is not fully understood.

2. FGF18

FGF18 is a highly conserved protein composed of 207 amino acids, with 30% to 70% homology with other members of FGFs found. FGF18 exists in a variety of cell types, and its function is not limited to skeletal development, but can stimulate the proliferation of numerous mesenchymal cells, epithelial cells and tissues, including lung, kidney, heart, testis, spleen, skeletal muscle and brain. As a member of the growth factor family, FGF18 plays an important role in morphogenesis, tumor growth and other cellular and tissue development. Compared with other growth factors except wound surface repair, FGF18 has potential clinical value in the treatment of skeletal diseases such as chondrodysplasia, chondroplasia and bone repair, with a wider range of effects. The decreased expression of FGFR3 was also observed by studying the FGFR3 and STAT1 signaling pathways, suggesting that FGF18 may play a role independent of FGFR3.

3. FGF23

FGF23 is an endocrine protein synthesized by osteoblasts and osteoblasts. It has been confirmed that the main role of FGF23 is to regulate the level of blood phosphorus as a hormone, which plays an important role in the metabolism of calcium and phosphorus, parathyroid gland, as well as participates in the regulation of bone mineral metabolism. FGF23 is a protective factor for kidney, promoting urinary phosphorus excretion and maintaining stable blood phosphorus metabolism.

In addition, FGF also has powerful functions and deep repair effect. The study of FGFs plays an immeasurable role in modern clinical medicine, surgery and cosmetic surgery.

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  1. 1.Definition of vaccine adjuvant?

What is a vaccine adjuvant? Before answering the question, let’s see what is an adjuvant. Adjuvant, also known as immunomodulator or immunepotentiator, originated from the Latin word "Adjuvare" and is meant to aid or enhance. An adjuvant is an additive of a vaccine. When it is mixed with an antigen and injected into the body, it can enhance the body's immune response to the antigen or change the type of immune response. It is a non-specific immunopotentiator and itself has no antigenicity. The ideal adjuvant not only enhances the immune response, but also provides the body with optimal protective immunity.

  1. 2.Application of vaccine adjuvant

(1) Enhancing the immunogenicity, immune response rate and tolerance of purified or recombinant antigens;

(2) Reducing the amount of antigen or the amount of inoculation required to achieve immunoprotection;

(3) Improve the immune efficacy of vaccines in infants, the elderly or people with impaired immune systems;

(4) As an antigen delivery system that takes up antigen through the mucosa, it can promote the absorption of the vaccine by the gastrointestinal mucosa. The concept of adjuvants is derived from ulcers formed at the site of inoculation and promotes the production of high levels of specific antibodies, even those produced by inoculation of unrelated substances can induce the production of highly specific antibodies;

(5) Adjuvants can increase the infiltration of cells, prevent antigen degradation, transport antigens to specific antigen-presenting cells, enhance antigen presentation or induce cytokine release.

  1. 3.Classification of adjuvants

At present, there is no uniform standard for the classification of adjuvants in the world. According to the chemical composition, it can be divided into aluminum salt adjuvant, protein adjuvant, nucleic acid adjuvant, lipid-containing adjuvant and mixed adjuvant.

(1) Aluminum salt adjuvant

Aluminum salt has been used clinically for more than 80 years and is the first classic adjuvant approved by the US FDA for human use. Many vaccine ingredients contain aluminum salts such as DTP vaccine and Haemophilus influenzae vaccine. Depending on the preparation process, vaccines with aluminum salts as adjuvants can be divided into two types: aluminum adsorption vaccines and aluminum precipitation vaccines. The aluminum adsorption vaccine is to add an antigen to an aluminum hydroxide or aluminum phosphate solution; and the aluminum precipitation vaccine is to add an aluminum suspension to the antigen solution. Aluminum hydroxide or aluminum phosphate is an aluminum adjuvant that is often used. The study found that aluminum adjuvant vaccine can reduce the amount of antigen used and enhance the strength and durability of the body's immune response. The mechanism of action of aluminum salts is still not clear. It is generally believed that the antigen-adsorbed aluminum salt particles form a gel state and are injected into animals to form an antigen reservoir. These insoluble particles can adsorb antigenic substances and increase the surface area of the antigen. In addition, the adjuvant can form a macrophage-rich granuloma at the injection site, delaying the absorption of the antigen, thereby prolonging the stimulation time of the antigen, and retaining the antigen for several days under normal conditions for a few weeks, and the antigen is taken at the injection site. Ability is enhanced. Studies have shown that aluminum hydroxide as an adjuvant can also activate Th2 cells to secrete IL-4, induce the expression of CD83, CD86 and MHC-II molecules, and then produce a Th2 type humoral immune response. Aluminum salts have many advantages as vaccine adjuvants, but there are also deficiencies. Although it can effectively induce a humoral immune response, it does not act on cellular immunity and cannot induce a cellular immune response.

(2) Protein adjuvant

Most of protein adjuvants belong to small molecule polypeptides or glycoproteins. A class of biologically active substances synthesized and secreted by immune cells and certain non-immune cells, generally cytokines, play an important role in the differentiation of Th cells. It can also enhance the function of NK cells and T lymphocytes, and has a wide-ranging effect on the immune response of the body. The use of a protein adjuvant in combination with an antigen enhances the immunogenic efficacy of the vaccine, and it can also be assembled into a plasmid and mixed with the antigen for injection. IL-12 is produced by monocytes and B cells and has a variety of biological activities. It can significantly reduce the number of bacterial invasions and increase the expression levels of IgG2a and IgA in the mucosa and immune system. It is a cytokine with broad application prospects. Adjuvant. It induces a Th1-type immune response, and the treatment of tumors and AIDS is in clinical trials.

 (3) Nucleic acid adjuvant

In the process of researching vaccines, some nucleic acid substances are also found to have the characteristics of adjuvants. The most representative one is CPG DNA, in which the unmethylated cytosine deoxynucleotides and guanine deoxynucleotides are Unit oligomers, agonists of TLR9, are currently a hot spot in adjuvant research. It plays an important role in enhancing specific immune responses, inducing non-specific immune responses in the body, and regulating the type of immune response. The characteristic sequence of CPG-ODN can activate a variety of immune effector cells, such as T cells, B cells and NK and other immunocompetent cells, so CPG-ODN is used in more experimental studies. Bacterial DNA is a source of CPG-ODN, and its role includes enhancing both humoral and cellular immunity. It is more likely to be used in tumors and infectious diseases. It has not been reported that CPG-ODN has serious side effects on humans, but it has been found in animal models that CPG-ODN can induce autoimmune diseases.

(4) Lipid-containing adjuvant

Lipid-containing adjuvants include lipopolysaccharide (LPS) and liposomes. LPS is a Gram-negative bacterial outer membrane lipopolysaccharide, and lipid A is the main component of adjuvant action in LPS. The researchers co-immunized mice with LPS as an adjuvant to pertussis vaccine. The results showed that LPS not only improved the immune efficiency of the vaccine, but also reduced the occurrence of type I hypersensitivity. Liposomes are similar to biofilms. Ultrafine spherical preparations, usually formed by bilayers of phospholipids and cholesterol coated with antigens, are capable of transporting antigens and as adjuvants for vaccines. Liposomal adjuvants are not toxic and can reduce the toxicity of the antigen and can degrade in the host itself. Studies have shown that liposome vaccine delivery can enhance the body's humoral and cellular immune responses, and the structure of the liposome facilitates the presentation of antigens to antigen-treated cells. Studies have also shown that liposomes combined with Freund's reagent or aluminum hydroxide have a multiplier effect. However, it also has shortcomings, such as poor stability, easy oxidation, and high production costs. Therefore, current research on the application of liposomes has been suspended for medical research.

(5) Mixed adjuvant

MF59 is an oil-in-water emulsion which is a uniform droplet emulsion formed by mixing Tween 80, sorbitol trioleate and squalene under high pressure conditions. This mixed adjuvant can induce a local immune stimulating environment at the injection site, increase chemokines, cytokine levels, and accumulate MHC+ cells in the muscle. In addition, MF59 is also able to enhance the ability of dendritic cells to take up antigen. Because MF59 enhances the immunogenicity of influenza in people with low immunity, it was certified as an adjuvant to influenza vaccines in the 1990s. A large amount of data shows that MF59 is safer for influenza vaccines.

(6) Aggregate structure adjuvant

The researchers compared the immunopotentiating effects of three novel molecular aggregate formula adjuvants [RAM1, Glycolamide (RAM2) and 5th generation dendrimer (RAM3)] and evaluated these adjuvants ability of an adjuvant to enhance a Th1 or Th2 response when applied with a soluble protein antigen. In this study, ovalbumin (OVA) was used as an antigen, and the above three new aggregates were adjuvants, and tuberculin, Al (OH)3, and Freund's incomplete adjuvant were used as controls. Results RAM1 was superior to other adjuvants in the three adjuvants, and the induced cytokines were mainly Th1 type, and induced a Th2-type response in the late stage of inoculation. In this study, ovalbumin (OVA) was used as an antigen, and the above three new aggregates were adjuvants, and tuberculin, Al (OH)3, and Freund's incomplete adjuvant were used as controls. Results RAM1 was superior to other adjuvants in the three adjuvants, and the induced cytokines were mainly Th1 type, and induced a Th2-type response in the late stage of inoculation.

To be continued in Part Two.

Reference

[1] Aguilar J C, Rodríguez E G. Vaccine adjuvants revisited[J]. Vaccine, 2007, 25(19):3752-3762.

[2] Coffman R L, Sher A, Seder R A. Vaccine Adjuvants: Putting Innate Immunity to Work[J]. Immunity, 2010, 33(4):492-503.

[3] Mata-Haro V, Cekic C, Martin M, et al. The Vaccine Adjuvant Monophosphoryl Lipid A as a TRIF-Biased Agonist of TLR4[J]. Science, 2007, 316(5831):1628-1632.

[4] O'Hagan D T, Valiante N M. Recent advances in the discovery and delivery of vaccine adjuvants[J]. Nature Reviews Drug Discovery, 2003, 2(9):727-35.

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What is TCR?

T cells are the main functional cells in the acquired immune system, which are responsible for identifying antigens and directing other immune cells to carry out immune responses. T cell antigen receptor on T cell surface plays a key role in antigen recognition. T cells play an important role in the immune system and can attack pathogens and cancer cells. T cell receptor (TCR) can recognize different ligands with wide affinity and participate in activating various physiological processes. TCR cell therapy customizes functional TCR, which has the best antigen recognition characteristics and uses the human immune system to fight cancer.

The structure of TCR

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Figure 1. The structure of TCR

T cells are the main components of adaptive immune response. The structure of their antigen recognition receptors has been confirmed. The cloned TCR consists of alpha and beta chains as heterodimers. TCR heterodimers mainly bind to several signal transduction subunits of CD3, CD3gamma, CD3delta and CD3E heterodimers and CD3delta homologous dimers. Different subunits of CD3 contain the activation sequence of tyrosine, the immune receptor, ITAM, but the number of each subunit is different. CD3gamma, CD3delta and CD3epsilon contain one, respectively, while CD3delta contains three tandem ITAMs, so that each T cell receptor can produce 10 ITAMs. Tyrosine phosphorylated ITAM can couple TCR with intracellular signal transduction pathways and recruit SH2 domain proteins, such as tyrosine kinase ZAP70, from TCR. However, there are still two hypotheses to explain why TCR complex contains so many signal transduction subunits and ITAM. One is that CD3 or ITAM alone may perform different signal transduction functions by recruiting unique effector molecules, and the other is that the main function of multiple TAMs is to amplify TCR signals.

TCR signaling pathway

TCR recognizes a peptide that binds to MHC molecules presented by antigen presenting cells (APCs). Single TCR can recognize different ligands (auto-peptide and foreign-peptide) with wide affinity. TCR is involved in triggering different functional outputs. In thymus, the binding intensity of pMHC and TCR signals determines the process of cell development and differentiation. When the binding force is between the minimum and the maximum, it promotes the survival of thymocytes and transforms into the mature stage of CD4*CD8 or CD4CD8*. If the TCR and pMHC are too low or too high, cell apoptosis will occur. Peripherally, the low affinity binding of autologous pMHC to TCR provides the strong survival signal necessary to maintain the initial T cells, and also promotes the full activation of autologous pMHC in high affinity encounters with foreign antigens.

The intensity of TCR signal is crucial for the production of appropriate T cells. TCR signal transduction response guides the successful differentiation of CD4* T cells into different T helper cell subsets, and plays a key role in specific T helper cell subsets. The intensity and duration of TCR cells are related to the differentiation of memory T cells, and are also the basic determinants of T cell impotence or depletion. TCR signal is regulated by biochemical and molecular mechanisms, leading to signal amplification or attenuation. The mechanism of TCR regulation is complex and diverse, but it can be divided into three basic levels: early signal transduction effector molecule; signal molecule development stage; and dynamic regulation of TCR signal intensity.

TCR binds to the MHC complex expressed on antigen presenting cells (APC) to activate TCR signaling pathway. SRC family protein tyrosine kinase LCK binds to the cytoplasmic domain of CD4 and CD8 common receptors, and is recruited to TCR through the co-binding of CD8 or CD4 with MHC or MHC class I complexes, respectively. LCK phosphorylation enables protein tyrosine kinase ZAP70 to bind to the CD3 chain. T cell activation cohesion factor LAT is phosphorylated, activated T cells, recruited multiple cohesion factors and effector molecules, forming LAT signal transducers. Activation of LAT-related effector molecules leads to signal transduction through three main signaling pathways: calmodulin, MAPK and NF-KB signaling pathways. Calmodulin signal transduction activates T cell nuclear factor (NFAT) for nuclear translocation; MAPK signal transduction leads to actin aggregation and activation of transcription factors FOS, JUN, AP-1; and NF-K B signal transduction causes nuclear translocation of REL and NF-K B transcription factors: These transcription factors synergize to cause T cell proliferation, migration, cytokine production and effect function. TCR is also usually associated with the activation of its common receptor CD28 or cytokine receptors (such as PI3K, AKT, PIP3, PTEN, JAK, STAT) and other signaling pathways.

Application of TCR

Tumor therapy

T cells were modified by TCR gene to exert specific immune regulation or cytotoxic activity. It has great potential in the treatment of malignant tumors and other diseases. Tumor-associated antigen-specific TCR gene was transduced into T lymphocyte for the treatment of tumors, starting with melanoma.

In addition to melanoma, some scholars have recently attempted to extend TCR gene therapy to the treatment of colorectal cancer, synovial cell carcinoma, neuroblastoma, lymphoma and other tumors.

TCR DNA vaccine

TCR gene can be used as a target gene for therapy besides being a guide gene for targeted therapy. In recent years, the use of TCR DNA vaccine to treat some diseases has been gradually carried out. TCR DNA vaccine is a kind of gene vaccine. Through the expression of antigen protein in the body, the body can induce specific immune response, selectively kill pathogenic T cells or inactivate them to play a therapeutic role.

The future of TCR

At present, two research hotspots in the field of TCR gene therapy are: (1) mutation of CDR region to improve the affinity of TCR transduction; (2) pairing of TCR A and beta chains. There are three main problems in TCR gene therapy in the future: (1) in vivo environment of T cells after transfusion; (2) quality problems of T cells after transfusion; (3) safety of transduction of TCR.

In TCR gene therapy, antigen-specific TCR gene modified T cells in tumors and infectious diseases have achieved exciting results, which has proved to be a promising therapeutic strategy. Antigen-specific TCR gene-modified T cells have replaced the traditional effector cells and become the hotspot of this field. Although there is still some distance from large-scale clinical application and becoming a conventional treatment method, it is believed that TCR gene therapy will become more and more perfect and play a greater therapeutic role with the deepening of research.

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Abstract: As a key genetically engineered antibody, single-chain antibody consists of three parts, the antibody light chain variable region, the heavy chain variable region and a segment of the bridge polypeptide chain. The single-chain antibody not only has strong targeting, but also is not easy to dissociate, has a simple structure, is easy to operate and transform, and is advantageous for antibody library screening. At present, there are two main ways to construct single-chain antibodies: 1. Amplification of antibody light chain and heavy chain variable regions from hybridism cell lines, but the construction of single-chain antibodies has a rejection reaction. 2. RNA was extracted from canine spleen B lymphocytes, reverse transcribed into cDNA, and antibody variable region was obtained. The phage display antibody library technology is a new technology currently available for the preparation of human monoclonal antibodies. It uses the RT-PCR method to amplify the human immunoglobulin full set variable region gene and then recombine into the prokaryotic expression vector, and forms a fusion protein with the phage coat protein to express the antibody fragment on the surface of the phage, and screens by panning. The specific variable region gene can conveniently and efficiently perform high-throughput screening of antibodies, and opens up a simple and rapid production route for the preparation of human monoclonal antibodies. A key aspect of this technology is the construction of a library of human phage antibodies.

Keywords: antibody library, single-chain antibody, construction

Phage single-chain antibody library for pancreatic cancer

Pancreatic cancer is one of the most malignant tumors known to date. Pancreatic cancer is the fourth leading cause of cancer death in Europe and America due to the insidious pancreatic cancer and lack of specific symptoms and signs. The phage antibody library technology has opened up new fields for the research of genetically engineered antibodies, and has been used in the diagnosis and prevention of infectious diseases, the identification of autoimmune diseases and viral diseases, imaging analysis of tumors and targeted therapy or gene therapy. The field shows great potential and broad application prospects. Compared with the traditional hybridism technology, the technology is simple, easy to produce, low in production cost, large in screening capacity, and can be prepared in large quantities by fermentation.

The total RNA of peripheral lymphocytes of patients was extracted, and the H chain and L chain variable region genes were amplified by RT-PCR. The VL fragments were randomly spliced into ScFv fragments by SOE-PCR. The ScFv fragment was then cloned into a specific vector and electroporated into a competent strain, rescued by the helper phage M13K07, and a human phage single-chain antibody library of pancreatic cancer was obtained, which aims to lay a foundation for the biological treatment of pancreatic cancer.

Pneumoconiosis phage single-chain antibody library

At present, pneumoconiosis is still the most common type of occupational disease in China with the highest incidence rate, the risk of death, and the most serious harm to workers. So far, there is no cure for it, which can only be eliminated or reversed according to the condition. Delaying the progression of the disease, therefore, active prevention and early diagnosis are particularly important to improve the quality of life and prolong life. The construction method is similar to the above and will not be described again.

Ribosomal display single-chain antibody library

Ribosomal display is a new technology for the screening and identification of functional proteins completely isolated, avoiding the drawbacks of traditional in vivo screening techniques, resulting in increased library capacity and enhanced molecular diversity. It binds the correctly folded protein and its mRNA to the ribosome, forming an mRNA-ribosomal-protein trimer that links the genotype and phenotype of the protein of interest. In recent years, ribosome display technology is built on a single-chain antibody library and applications have made great progress. The main processes of ribosome display technology include:

  • Construction of ScFv ribosome display template
  • ScFv single-chain antibody in vitro transcription and translation
  • Affinity screening and enrichment of ribosomal complexes
  • Evaluation of screening efficiency
  • In vitro evolution of ScFv molecules

The ribosome display technology is completely in vitro, and has the advantages of simple database construction, large library capacity, and simple screening method, no need to select pressure, and the like, and the introduction of mutation and recombination technology to improve the affinity of the target protein, so it is a large-scale construction. Because it can screen high-affinity protein molecules in a short period of time, its emergence opens up a new way to prepare small molecule antibodies. It is believed that with the continuous solution of shortcomings such as system stability in ribosome display technology, it will have great application value for the construction of antibody libraries and the screening of small molecule antibodies.

Anti-canine parvovirus single-chain antibody library

According to the larger bacterial display technology of bacterial particles, antibodies can be displayed on the surface of bacteria and the binding of antigen and antibody can be monitored by flow cytometry (FCM) in real time by fluorescent labeling, and the antibody-expressing strain with high affinity can be sorted. Using bacterial endometrial display technology, the foreign gene is expressed together with the NlpA signal peptide, and the target protein is displayed in the bacterial inner membrane. The NlpA signal peptide can transport the fusion gene of interest to the bacterial periplasmic space, and utilizes 6 specific amino acids to form a serotonin bond with the outer membrane of the bacterial endometrium during the transmembrane process, anchoring to the outside of the bacterial inner membrane to form a bacterial display antibody library. The outer membrane of the bacteria is treated with lysozyme, and the antibody library is screened by fluorescent labeling specific antigen binding to FCM. The method utilizes a 6 amino acid short peptide to anchor the foreign protein, has no effect on the conformation of the expressed antibody protein, and maintains genotype and phenotypic association. The aim is to screen recombinant antibodies with affinity anti-CPV gene, and lay a foundation for neutralizing active antibodies in subsequent studies. The neutralizing antibodies can bind to neutralizing epitopes on the virus, prevent the virus from binding to the corresponding receptors on the cell surface, and prevent diseases.

Evaluation

The ultimate goal of building a library is to screen out various specific antibody molecules. Whether the antibody of interest can be screened, in addition to the affinity of the antibody of interest and the target antigen, the quality of the library is also a determining factor. A library of antibodies with greater capacity and diversity will ensure the success of the screening. In general, the storage capacity is positively correlated with the affinity of the antibodies screened. High-affinity antibodies can only be screened in a high-capacity antibody library. At the same time, it must have good diversity. For natural antibody libraries, a wider range of antibody gene sources can better ensure the diversity of antibody libraries.

References

[1] Baca M, Presta LG, O 'Connor SJ, et a1. Antibody humanization using monovalent phage display [J].  J Biol Chem, 1997, 272:10678-10682.

[2] Lowenfels A B, Maisonneune P. Epidwminology and prevention of pancreatic cancer [J], Jpn J Clin Oncol, 2004, 349(5):238-242

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Wholesale Cat Food means that the prices of cat food are sold at a reduced price, meaning that you get a discount. You can get wholesale cat food which is sold on discount in many stores. Chicken & Brown Rice Dry Cat and Kitten food is one of them, it is combination of simple ingredient to meet needs and satisfy your cat. This is a real utilization of chicken meat and chicken meal as its core ingredient. The whole brown rice in the formula is a high source of carbohydrates and natural fiber. While sunflower oil provide Omega 3 and Omega 6 which are essential fatty acids for a healthy skin. This wholesale cat food is designed to meet the nutritional values that are set and leaves your cat full. It's packed on 5lb to 15 lbs and it's available for shipping when ordered on large quantity this way you save your money.

Herring & Sweet Potato Dry Cat Food is another food that can be found on wholesale cat food kit, this is a unique single source animal protein which is in herring. Sweet potato are good provider of antioxidant such as Beta-Carotene, vitamin A,C, and E, as well as potassium, Iron and other mineral more to this they add a sweet taste to the food. The presence of Oatmeal provides good source of carbohydrate energy. The natural source of this food is maintained by use of natural antioxidant this ensures that the package is fresh and the nutrition is intact and by this your cat gets a shiny coat.

Salmon & Sweet Potato is a combination of fresh wild-catch salmon and mackerel this gives your cat a simple meal. The use of Mackerel provides a high quality protein and it's a magnificent source of omega 3 fatty acids, which helps in structure of cell membranes. Fatty acids support growth, assist in development of nervous system. This diet is best for cats that do not like grains since it contains no grains.



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Have you ever pondered what your feline is stating? I'm certain most pet managers have every once in a while. When you figure out how to read non-verbal communication you can! Give careful consideration to what her tail, ears, and hide are doing and you can read their feelings.

Your felines' tail is the most vital part to watch to figure out your felines emotions. You can figure out whether your feline is cheerful or not by examining her tail.

Tail straight up: When your feline is strolling to you and her tail is straight up it is an indication of kind disposition, this is her method for welcome you in a well disposed way.

Tail straight up and shuddering: When your feline shows this she is exceptionally upbeat to see you, however in the event that your feline is a male be wary he may be getting primed to stamp his region when you get excessively close you may mourn it.

Tail straight up yet with a snare: This is normally seen when she is seeing a new individual or when approached by an alternate feline. When you see this she is readied to be agreeable yet readied to safeguard herself also.

Tail straight up and puffed: Look out on the grounds that your feline is pestered, furious, or startled. Better provide for some opportunity to cool off before approaching her.

Tail straight up and at a slight plot: She is unsure, readied to be agreeable additionally primed to flee or if important to battle.

Tail straight out and down: This feline is primed to battle, it could be she is prepared to play yet normally you can tell which one quite rapidly. So be extremely mindful when you see this conduct.

Tail goes up and afterward hangs down: Your feline is getting primed if important to shield herself.

Tail is tucked in: Your feline is frightened, assuming that she isn't cornered she will presumably fled, if cornered she will likely battle.

Tail whipping: Large abate swings typically mean she is energized however more diminutive swings and quickly moving shows outrage.

Your feline's ears are additionally a method for telling your feline's enthusiastic state. while not as evident as the tail when perusing both the tail and ears together you can show signs of improvement picture of how your feline feels.

Assuming that your feline's ears are back this typically implies animosity, assuming that they are both up and back this normally implies a test is constantly given.

The point when your feline's ears are out she is either apprehensive or exceptionally troubled, if the ears retreat significantly more she is undermined and may respond with animosity.

There are different signs your feline may provide for you, for example, murmuring, working, and rubbing with her head of face which we all know is an indication of warmth, however rubbing the head or face is likewise her method for fortifying her bond with you by exchanging some of her fragrance to you. Rubbing around your legs is likewise considered fondness which obviously it is however again she is holding with you by getting her aroma on you.

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A vigorous 60-minute workout on a treadmill affects the release of two key appetite hormones, ghrelin and peptide YY, while 90 minutes of weight lifting affects the level of only ghrelin, according to a new study. Taken together, the research shows that aerobic exercise is better at suppressing appetite than non-aerobic exercise and provides a possible explanation for how that happens.

This line of research may eventually lead to more effective ways to use exercise to help control weight, according to the senior author, David J. Stensel of Loughborough University in the United Kingdom.

Treadmill versus weight lifting

There are several hormones that help regulate appetite, but the researchers looked at two of the major ones, ghrelin and peptide YY. Ghrelin is the only hormone known to stimulate appetite. Peptide YY suppresses appetite.

Ghrelin was discovered by researchers in Japan only about 10 years ago and was originally identified for its role as a growth hormone. Only later did its role in stimulating appetite become known. Peptide YY was discovered less than 25 years ago.

In this experiment, 11 male university students did three eight-hour sessions. During one session they ran for 60 minutes on a treadmill, and then rested for seven hours. During another session they did 90 minutes of weight lifting, and then rested for six hours and 30 minutes. During another session, the participants did not exercise at all.

During each of the sessions, the participants filled out surveys in which they rated how hungry they felt at various points. They also received two meals during each session. The researchers measured ghrelin and peptide YY levels at multiple points along the way.

They found that the treadmill (aerobic) session caused ghrelin levels to drop and peptide YY levels to increase, indicating the hormones were suppressing appetite. However, a weight-lifting (non-aerobic) session produced a mixed result. Ghrelin levels dropped, indicating appetite suppression, but peptide YY levels did not change significantly.

Based on the hunger ratings the participants filled out, both aerobic and resistance exercise suppressed hunger, but aerobic exercise produced a greater suppression of hunger. The changes the researchers observed were short term for both types of exercise, lasting about two hours, including the time spent exercising, Stensel reported.

“The finding that hunger is suppressed during and immediately after vigorous treadmill running is consistent with previous studies indicating that strenuous aerobic exercise transiently suppresses appetite,” Stensel said. “The findings suggest a similar, although slightly attenuated response, for weight lifting exercise.”

Focus on active ghrelin

Previous studies have been inconclusive about whether exercise decreases ghrelin levels, but this study may help explain those mixed results, according to the researchers.

Ghrelin comes in two forms, acylated and non-acylated. The researchers measured acylated ghrelin, also called active ghrelin, because it can cross the blood-brain barrier and reach the appetite center in the brain. Stensel suggests that future research concentrate on active ghrelin.

While the study showed that exercise suppresses appetite hormones, the next step is to establish whether this change actually causes the suppression of eating.

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Superoxide dismutase, alias liver protein, abbreviation: SOD. SOD is an active substance derived from living organisms, which can eliminate harmful substances produced in the process of metabolism. Continuously replenish SOD on human body has special effects on anti-aging. Superoxide dismutase (SOD) was first isolated from bovine red blood cells in 1938. People have studied SOD for more than 70 years. McCord and others rediscovered the protein in 1969, and found its biological activity, and clarified its catalytic properties of peroxide anion disproportionation reaction, so it was formally named superoxide dismutase.

Superoxide dismutase is a new enzyme preparation. It is widely distributed in the biological world, almost from animals to plants, even from people to single-celled organisms, have its existence. SOD is regarded as the most magical enzyme in life science and technology, and garbage scavenger in human body. SOD is the natural enemy of oxygen free radicals, is the number one killer of oxygen free radicals in the body, is the basis of life and health.

The oxygen free radicals is an atomic group containing an unpaired electron, it spread in a lots of biocatalyst, such as lignin peroxidase, lactoperoxidase and so on. As atoms form molecules, electrons in chemical bonds must appear in pairs, so free radicals grab one of the electrons of other substances everywhere and form stable substances themselves. In chemistry, this phenomenon is called "oxidation". Our biological system mainly encounters oxygen free radicals, such as superoxide anion free radicals, hydroxyl free radicals, lipoxy free radicals, nitrogen dioxide and nitric oxide free radicals. Hydrogen peroxide, singlet oxygen and ozone are commonly referred to as reactive oxygen species. Reactive oxygen species in the body have certain functions, such as immunity and signal transduction. However, excessive reactive oxygen species (ROS) can cause damage to normal cells and tissues, leading to a variety of diseases. Such as heart disease, Alzheimer's disease, Parkinson's disease and cancer. In addition, sunlight radiation, air pollution, smoking, pesticides and so on in the external environment will cause the human body to produce more reactive oxygen species free radicals, so that nucleic acid mutation, which is the root cause of human aging and disease.

Superoxide dismutase (SOD) is naturally formed in the human body. It can antagonize and block the damage caused by oxygen free radicals and repair damaged cells in time. With age, the body's ability to form superoxide dismutase is getting worse and worse, and disease and aging are catching up. This shows how superoxide dismutase acts very miraculous and important.

SOD is a natural scavenger of oxygen free radicals in living organisms. It has a wide range of medical value and can be used as additives in medicine, food and daily chemical products. SOD is approved for clinical use and shows a powerful regenerative repair capability for some tissue sclerosis and fibrosis caused by age, disease or injury. SOD has been successfully applied to adjuvant therapy after radiotherapy, to control the progression of heart disease, and to treat severe rheumatoid arthritis. In Denmark, SOD is used to treat rheumatoid arthritis.

Superoxide dismutase (SOD) is widely used in cosmetic additives, such as SOD mask, SOD honey, SOD snake powder and other cosmetics manufactured by superoxide dismutase.

SOD is used as a supplementary food, and people try every possible way to maintain a high level of SOD in the body, that is, to provide appropriate nutrients for the liver to synthesize SOD while consuming food, or directly wrap the exogenous SOD in food protein, through the digestive system without being digested, into other parts of the body.

The development of SOD in medical application depends on the further study of its mechanism of action and production, and we expect to find the factors promoting SOD production. Because of the different sources of SOD and different detection methods, SOD activity is not comparable. It is expected that international standards should be standardized with scientific, simple and practical principles. Due to the blockage of animal blood SOD in the European Union, the development of plant and microbial SOD has become a promising industry direction.

As for the industrial enzyme production of the superoxide dismutase, it is a complex access, so for more information, you can click here to visit our website.

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Laccase is a polyphenol oxidase containing four copper ions (p-bisphenol oxidase, EC1.10.3.2), belonging to the copper blue oxidase, in the form of monomer glycoprotein. Laccase exists in mushrooms, fungi and plants, and can also exist in the air. The only product after the reaction is water, so it is essentially an environmental-friendly antioxidant enzymes. Laccase has a wide range of applications in biological detection because of its unique catalytic properties. As an efficient biodetector, laccase has become an effective tool and means for the analysis of substrates, coenzymes, inhibitors and other components. Laccase has become the research object of many scholars in recent years because of the importance of environmental protection consciousness.

Laccase is the largest type of blue poly-copper oxidase, which has the catalytic properties of oxidizing polyphenols by comt and reducing oxygen to water. As early as 1883, Yoshida first discovered laccase in Japanese lacquer tree, becoming one of the earliest discovered enzymes in the world. Plant laccase has been neglected for a long time due to its lack of industrial application value. In the continuous development of biotechnologies such as removing polyphenols from industrial wastewater and lignin and pigments from textile printing and dyeing, laccase can oxidize polyphenols, lignin and other chemicals by using oxygen as an electron acceptor and produce the only by-product water. High quality conditions make the catalytic properties of laccase have wide application prospects in environmental protection, textile, printing and dyeing, food, chemical synthesis, and become one of the focus of scientific circles in the last decade. The research and development of new laccase, the space structure of laccase and its catalytic mechanism, the properties and application of laccase have become the focus of scientific research. Researchers in China have gradually realized the advantages of laccase in industrial applications, and the research momentum in recent years is swift and violent.

Large-scale industrialized production of microbial enzymes, which is a kind of whole cell biocatalysis and known as biotechnology or green chemistry, is one of the major areas of bio-economy advocated by Europe. Enzymes that can be used in industrial production must have some good properties, such as high temperature resistance, strong alkali resistance, resistance to shear force, and no inactivation during a certain storage period. The application range of fungal laccase is pH 4-6, temperature 30-50 C, and many substances are sensitive. Chloride, azide compound, hydroxide and so on can inhibit the activity of fungal laccase. In order to improve the properties of laccase and reduce the enzyme production cost, it is an effective method to express heterologous laccase by genetic engineering. However, because fungal laccase is a glycoprotein, and its glycosyl group has an important influence on the properties and activity of laccase, the heterologous expression of fungal laccase is difficult. Up to now, no successful expression of fungal laccase in E. coli has been reported.

In a word, laccase is a kind of polyphenol oxidase, because it is widely distributed in nature, and has a wide range of applications in environmental protection, textile, printing and dyeing, food, chemical synthesis and so on, in recent years has been widely concerned and studied.

Bacterial laccase can make up for the shortcomings of lipoxygenase, which generally does not have glycoprotein, and is easy to heterologous expression, genetic modification and large-scale fermentation production. The optimum pH for bacterial laccase is alkaline environment, high temperature resistance, and insensitive to inhibitors. As Wang reported, the half-life of laccase produced by Bacillus subtilis WD23 was 2.5 h at 80 C and 15 d at pH 9. A laccase was obtained from Bacillus C-125. The optimum pH of laccase was 7.5-8. Chloride did not inhibit laccase but stimulated laccase activity. Bacterial laccase shows great potential for application. But there are too few studies on bacterial laccase that seriously hamper the application of bacterial laccase. Therefore, it is of great significance to carry out extensive research on bacterial laccase.

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Hydrogen peroxide, chemical formula H2O2. Pure hydrogen peroxide is a light blue viscous liquid that is miscible with water in any proportion. It is a strong oxidant. The aqueous solution is commonly called hydrogen peroxide and is a colorless transparent liquid. Its aqueous solution is suitable for medical wound disinfection and environmental disinfection and food disinfection. Under normal circumstances, it will slowly decompose into water and oxygen, but the decomposition rate is extremely slow, and the speed of the reaction is accelerated by adding a catalyst such as manganese dioxide or the like, or irradiating with short-wave radiation.

 

Oxidation and reduction in different cases. Used for photographic decontaminants; color positive blue thinning; film over-scale thinning. Very easy to break down, not easy to live for a long time.

On October 27, 2017, the World Health Organization's International Agency for Research on Cancer published a preliminary list of carcinogens, hydrogen peroxide in the list of three types of carcinogens.

 

Physical properties

The aqueous solution is a colorless transparent liquid, soluble in water, alcohol, ether, and insoluble in benzene and petroleum ether.

Pure hydrogen peroxide is a light blue viscous liquid with a melting point of -0.43 ° C and a boiling point of 150.2 ° C. The pure hydrogen peroxide will change its molecular configuration, so the melting point will also change. The solid density at the freezing point was 1.71 g/cm3, and the density decreased as the temperature increased. It has a greater degree of association than H2O, so its dielectric constant and boiling point are higher than water.

 

Chemical properties

Oxidative

Pure hydrogen peroxide

(Lead white in the oil painting [basic lead carbonate] will react with hydrogen sulfide in the air to form black lead sulfide, which can be washed with hydrogen peroxide)

Principle: lead sulfide→lead oxide→basic lead carbonate

(requires alkaline medium)

  1. Reducing The reaction with a strong oxidizing agent such as chlorine or potassium permanganate is oxidized to form oxygen.
  2. In 10 mL of 10% sample solution, 5 mL of diluted sulfuric acid test solution (TS-241) and 1 mL of potassium permanganate test solution (TS-193) were added. There should be bubbles and the purple-red potassium permanganate disappears. It is acidic to litmus. In case of organic matter, it is explosive.
  3. Take 1 g of sample (accurate to 0.1 mg) and dilute to 250.0 mL with water. Take 25 mL of this solution, add 10 mL of dilute sulfuric acid test solution (TS-241), and titrate with 0.1 mol/L potassium permanganate. 0.1 mol/L per ml. Potassium permanganate corresponds to 1.70 mg of hydrogen peroxide (H 2 O 2 ).
  4. In the case of organic matter and heat, it releases oxygen and water, and reacts violently with chromic acid, potassium permanganate, metal and carbonic acid. [2] In order to prevent decomposition, a trace amount of a stabilizer such as sodium stannate, sodium pyrophosphate or the like may be added.
  5. Hydrogen peroxide is a very weak acid: H2O2 = (reversible) = H++HO2-(Ka = 2.4 x 10-12). Therefore, the peroxide of the metal can be regarded as its salt.
  6. Pure hydrogen peroxide is very unstable, and it is violently decomposed into water and oxygen when heated to 153 °C.

 

Use

The use of hydrogen peroxide is divided into three types: medical, military and industrial. The daily disinfection is medical hydrogen peroxide. The medical hydrogen peroxide can kill intestinal pathogenic bacteria, pyogenic cocci, and pathogenic yeast, which are generally used for surface disinfection of objects. Hydrogen peroxide has an oxidation effect, but the concentration of medical hydrogen peroxide is equal to or lower than 3%. When it is wiped to the wound surface, it will burn, the surface will be oxidized into white and bubble, and it can be washed with water. After 3-5 minutes Restore the original skin tone.

 

Hydrogen peroxide bleaching mechanism

The chemical industry is used as a raw material for producing sodium perborate, sodium percarbonate, peracetic acid, sodium chlorite, thiourea peroxide, etc., oxidizing agents such as tartaric acid and vitamins. The pharmaceutical industry is used as a bactericide, disinfectant, and an oxidant for the production of thiram and 40 liters of antibacterial agents. The printing and dyeing industry is used as a bleaching agent for cotton fabrics and for chromogenic dyeing. Removal of iron and other heavy metals when used to produce metal salts or other compounds. Also used in electroplating baths to remove inorganic impurities and improve the quality of the plated parts. Also used for bleaching wool, raw silk, ivory, pulp, fat, etc. High concentrations of hydrogen peroxide can be used as a rocket power improver.

Civil use: to deal with the smell of kitchen sewers, to the pharmacy to buy hydrogen peroxide plus water plus washing powder poured into the sewer can be decontaminated, disinfected, and sterilized;

3% hydrogen peroxide (medical grade) for wound disinfection;

 

About us

Starting from a small supplier of proteins and enzymes for academic institutes and biotech companies, Creative BioMart has always been focusing on developing high quality protein products and efficient protein manufacturing techniques. Here are some products:JAG1LIPGMAPK13Mcl1,etc.

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The development of nucleic acid vaccine marks the arrival of the third vaccine revolution. In 1995, the New York Academy of Sciences held a conference on nucleic acid vaccines, which was called the new era of vaccines and the third revolution of vaccines.

Nucleic acid vaccine, also known as gene vaccine or DNA vaccine, is also called naked nucleic acid vaccine because it does not need carriers and adjuvants for intramuscular injection. By intramuscular injection, the vaccine can obtain a more durable antigen expression in myocytes. The antigen can induce antibody production, T cell proliferation and cytokine release, especially the killing effect of cytotoxic T cells. Specific immune response mediated by cytotoxic T cells plays an important role in anti-tumor, anti-virus and elimination of intracellular parasitic infections. Nucleic acid vaccine has attracted much attention among many vaccines because of its unique advantages.

The unexpected results of Wolf. and Arthur's gene delivery system provided conditions for the discovery of nucleic acid vaccine. In the late 1980s and early 1990s, gene therapy experiments were carried out with nucleic acids expressing gene products. Nude genes without any treatment can express proteins in muscle cells. This product can be expressed in skeletal muscle cells for two months and induce immune response in the body, thus triggering a research upsurge of nucleic acid vaccine.

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In the initial animal experiments, there were two encouraging results: the first was that influenza A virus nucleic acid vaccine was injected into mice, which resulted in the production of antibodies and cytotoxic T cells in mice and will take the Vaccine Preclinical Assessment in need. Then the mice were attacked with influenza A, and 100% of the mice in the control group survived in health, while 100% of the mice in the control group died nine days later. Almost at the same time, Fernand. used gene guns and nucleic acids encoding erythrocyte agglutinins, which resulted in protective immune responses in mice. Another important research result is the DNA vaccine of hepatitis B surface antigen. This vaccine can not only induce animals to produce corresponding antibodies, but also, more importantly, can make the HBsAg of transgenic animals negative. This indicates that nucleic acid vaccine can be used for the prevention or treatment of diseases, especially for the development of hepatitis B nucleic acid vaccine approach the medical dusty into vaccine Scale-up Development. This provides a promising direction for the research of hepatitis B vaccine in China at present.

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The research progress of nucleic acid vaccine is encouraging, because nucleic acid vaccine has many advantages, especially the dual functions of immune prevention and treatment. Since 1994, the Food and Drug Administration of the United States has successively approved nucleic acid vaccines such as AIDS, influenza, hepatitis B, simple scar, malaria and carcinoembryonic antigen to enter clinical trials. Many vaccine companies in Europe and the United States have invested a lot of manpower and material resources in the development and research of nucleic acid vaccine.

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  1. What is a biomarker?

Biomarkers are biochemical indicators that can be used to label changes in systems, organs, tissues, cells, and subcellular structures or functions, or to make changes, by measuring biochemical, cellular, and tissue responses, using biochemistry, immunology. genetics and other methods to indicate the presence or absence of pollutants and the response of biological individuals. Biomarkers can be directly sensitive to target cells or target molecules in vivo. Biomarkers have a very wide range of uses and can be used for disease diagnosis, for judging disease staging, or for evaluating the safety and efficacy of new drugs or new therapies in the target population.

Biomarkers are a necessary complement to conventional bioassays and can be used to form a complete biomonitoring system. In addition to chemical testing, a complete and comprehensive monitoring system needs to consider biological effects at various tissue levels, including individual or sub-individual levels, as well as biological effects at the population and community levels. Using advanced proteomics techniques to find relevant biomarkers in samples, surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS) can be used to screen disease-associated biomarkers using reversed-phase high performance liquid chromatography (RP-HPLC was used to separate and purify the sample, and the target protein was tracked by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The potential protein markers were identified by LC-MS/MS.

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  1. Classification of biomarkers

Based on functions, biomarkers are generally divided into:

Nutritional biomarkers (marker of exposure): reflect the content of exogenous substances or their metabolites or exogenous substances interacting with certain target cells and target molecules in the biological material of the organism, including two types of markers reflecting internal dose and biological effect dose.

Effect Biomarkers: Indicators of biochemical, physiological, behavioral, or other changes that can be measured in the body, including early biological effects, structural or functional changes, and markers of disease.

Sensitive biomarkers: reflects the body's innate or acquired indicators of its ability to respond to exposure to exogenous substances.

  1. Principles of biomarker selection

(1) The selected biomarker must have a certain specificity.

(2) The selected biomarker must have sufficient sensitivity that the level of the selected marker has a dose-response relationship with the level of external contact, and this relationship can be maintained at the level of innocuous contact.

(3) Repeatability and individual differences in the selected biomarker analysis are within acceptable limits.

(4) The selected biological standard should have sufficient stability to facilitate the transportation, preservation and analysis of the sample.

(5) When sampling, it is best to be non-destructive to the human body and acceptable to the subject.

  1. Characteristics of biomarkers:

(1) Has a certain sensitivity, the sensitivity should be higher than the general biological detection index, can be measured at low dose, and can be operated in a small amount. (2) Has the time effect of the reaction. The reaction must have a certain settling time and be fast. (3) The effect of the effector markers on the molecular and biochemical levels is closely related to the effects at the advanced biological level (such as growth and reproduction), and the effects at all levels must have a causal relationship. (4) Has a certain field application value. (5) It is required to select indicators that have less damage to the tested organisms, and the technology is easy to grasp. (6) Specific and early warning (eg, AchE).

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  1. How do you detect biomarkers in different cancers?

World Health Organization (WHO) statistics show that more than 80% of early malignancies can be cured! Early detection, early diagnosis, and early treatment are the keys to success. Therefore, how to detect cancer early to reduce mortality has become the focus of cancer prevention. In addition to clinical signs and imaging methods (such as X-ray, CT, MRI, B-ultrasound, colonoscopy, gastroscopy, etc.), early detection of cancer by tumor markers has become more and more important.

Tumor markers are biological signals that reflect the biological behavior of tumors. Combined detection of multiple tumor markers can detect tumors earlier than routine examinations (such as physical examination, X-ray, CT, MRI, B-ultrasound), and gain valuable time for treatment. Tumor marker detection can be used to: screening healthy populations, high-risk populations with family history or high risk factors; as a basis for early diagnosis, differential diagnosis, treatment testing, efficacy evaluation, recurrence and metastasis, prognosis, and search for therapeutic targets; tumors are detected early in asymptomatic conditions. For symptomatic people or high-risk populations, tumor markers have great reference value as indicators for census and health examinations. For example, elevated alpha-fetoprotein may indicate an increased risk of liver cancer in people who have had hepatitis and liver damage. Detection of prostate specific antigen (PSA) in elderly population tests is also a primary reference for male prostate cancer. For subjects with positive initial detection of tumor markers and no abnormalities, it is recommended to check every four to six weeks. If the retest result is negative, the possibility of tumor exclusion is naturally excluded (probably a transient increase in benign disease); if it continues to be positive for three consecutive times, it should be highly valued, consult a specialist, ask for a detailed history and conduct a physical examination. And combined with a variety of imaging examinations for tumor

There are many kinds of biomarkers, such as disease markers, cancer biomarkers, immune biomarkers, etc. So, how do we detect different biomarkers?

An example of a tumor marker is examined: liver cancer. Hepatitis B virus carriers, men who love to drink alcohol, check alpha-fetoprotein and B-ultrasound every six months after age 35. Liver cancer is a relatively high-risk disease in China. The high-risk age is 40-50 years old. Its important cause is viral infection--hepatitis, especially hepatitis B and hepatitis C, and even hepatitis carriers. These people are very likely to develop liver cancer after the age of 40.

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