71 results about "DNA degradation" patented technology

The invention discloses a stool sample preservation liquid, a preparation method and application thereof. Specifically, the stool sample preservation liquid contains: 45 vol%-60 vol% of a fixing agent; 0.1 mass%-15 mass% of a fixing agent adjuvant; 0.01 mass%-1.5 mass% of an anticoagulant; 10 vol%-15 vol% of a buffer solution; 0.01 mass%-1 mass% of an ionic strength maintenance agent; 0.01 vol%-0.5 vol% of a nonionic detergent; and the balance water. The stool sample preservation liquid provided by the invention has the characteristics of easy preparation and low cost, can preserve stool samples at room temperature, also can effectively inhibit DNA degradation and cell damage of stool samples, maintain cell shape, and can preserve samples for a long time, and the preserved samples have high qualification rate during reutilization.

The present invention relates to sirtuin 6 activating peptides, derived from highly conserved regions of human SIRT proteins, and to a cosmetic or pharmaceutical composition comprising at least one sirtuin 6 activating peptide in a physiologically acceptable medium. The invention further relates to the utilization of a cosmetic composition to prevent and/or repair DNA degradation, improve telomere maintenance and reduce cellular senescence. The invention also applies to a cosmetic treatment process intended to prevent and/or treat the cutaneous signs of aging and photo aging.

The invention provides a dura graft and a preparation method thereof. The dura graft is prepared from an acellular dermal matrix. The acellular dermal matrix is obtained from allogenic skin by crosslinking treatment, digestion treatment with a protease solution, decellularization with a hypertonic saline solution containing a surfactant, DNA degradation, amino acid nutrition treatment and freeze drying. The invention also provides applications of the dura graft in preparing repair materials used in the treatment of dural damage. The acellular dermal matrix is obtained from human skin tissue and undergoes physicochemical and biochemical treatment, so that all the components that may cause immunological rejection are removed. A fibrous stereoscopic scaffold structure of the original tissue is completely reserved, and new vessels and fibroblasts rapidly grow in the dura graft after implantation. Therefore, the dura graft has good clinical effects.

The invention belongs to preservation agents of blood samples and in particular relates to a blood preservation agent for protecting free DNA. Every 100ml of the preservation agent comprises the following components: 6.0-8.8g of an anticoagulant, 0.1-2.0g of a natural preservative, 4.8-11.7g of a DNA enzyme inhibitor, 5.0-10.0g of glucose, 5.0-8.0g of an antihemolytic agent, 0.1-0.5g of purine and the balance of buffer solution, totaling 100ml. The preservation agent disclosed by the invention can achieve the effects of effectively preventing blood cells from rupturing to release genome DNA so as to cause pollution, preventing degradation of free DNA in the plasma and providing a stable environment for the free DNA in the plasma. Moreover, the preservation agent is safe and non-toxic to the human body and environment and is favorable for accurate detection and analysis of the free DNA.

The invention relates to a methylation quantitative test method of APC gene in the DNA of human blood plasma. The methylation quantitative test method obtains venous blood and the blood plasma, prepares a DNA standard curve sample of the blood plasma, extracts the DNA of the blood plasma to be detected, the DNA of a standard curve blood plasma sample and the DNA of healthy human blood plasma, realizes chemical modification of the DNA of the blood plasma to be detected, the standard curve blood plasma sample and the healthy human blood plasma, designs particularity primers and Taqman fluorescent probes according to 707 CpG locus of a 1A sequence in a human APC gene sub-promoter, builds a standard curve according to the augmentation result of the DNA of the standard blood plasma after the augmentation, and implements methylation quantitative result analysis of the sample to be detected. The methylation quantitative test method of the APC gene solves the defects that the blood plasma has less DNA content, high loss rate, DNA degradation and carcinogenic pollutant, etc. The methylation quantitative test method of the APC gene utilizes a primer pair and a Taqman fluorescent probe that aim at the 1A sequence in the APC gene sub-promoter, realizes the detection aiming at the 707 CpG locus in the APC gene sub-promoter with high methylation developing rate, implements quantitative analysis, and can be used in the aspects of cure effect observing as well as prognosis and relapse monitoring of tumor patients.

A process of quantifying the extent of degradation present in a human DNA sample is described. The process makes use of a real time PCR system to separately quantitate within a sample a first retrotransposon interspersed element and a relatively longer second retrotransposon interspersed element, where the longer element is expected to be disrupted at a faster pace than is the shorter element as the sample degrades. In one embodiment, the process makes use of the appearance of the relatively young (on an evolutionary scale) Alu Yb-lineage subfamily sequences appearing in every human genome and their virtual absence in non-human samples. In a preferred embodiment, the process quantifies longer 290 bp sequences of “SVA” elements and shorter 80 bp sequences of Alu Yb8-lineage. Newly designed primers and TaqMan probes that are useful in the process are presented. A related process additionally quantifies male specific human DNA.

The invention discloses a nano di-cyclic aptamer probe and application thereof. The nano di-cyclic aptamer probe (G-dApR) is very stable and is not degraded by in-vivo DNA. Meanwhile, the biological activity of target cells can be effectively inhibited by combining specific recognition with a leukemia cell surface highly-expressive biomarker. The design of the probe is researched and developed based on two advanced technologies in the field of tumors, namely a ligand technology and a nanotechnology. Firstly, a conventional linear aptamer structure is transformed into a structure including a functional zone (specific) and a di-cyclic DNA zone (stable) by adopting a nucleic acid modification means, and the biological stability is greatly improved; secondly, the probe is finally established by combining a cyclic aptamer and a dendritic nano material PAMAM. The shortcoming that an aptamer is unstable is greatly overcome, an effective means is provided for leukemia detection, and high-sensitivity diagnosis and treatment integrated clinical application is achieved.

The invention provides an anal fistula patch or plug, as well as a preparation method and application thereof. The anal fistula patch or the anal fistula plug is prepared from an acellular dermal matrix. The acellular dermal matrix is obtained by performing protein enzyme solution digestive treatment, surfactant-containing hypertonic saline acellular treatment, crosslinking treatment, DNA degradation treatment and amino acid nutritional treatment on allogenic skin. The invention further provides application of the anal fistula patch or the anal fistula plug to preparation of a biological material for treating anal fistula. The acellular dermal matrix derives from human skin tissue, special physicochemical and biochemical treatment is conducted, all the components which may cause immunologic rejection are removed, the fiber three-dimensional stent structure of the original tissue is retained integrally, new vessels and fibroblasts grow quickly after implanting, and a good clinical effect is achieved.

The invention discloses a Y chromosome parting kit and its preparation method and application. The present invention designs three pairs of public primer pairs, optimizedly select 12 X chromosome STR loci suitable for the genetic distribution of Chinese population and designs MiniSTR primers fro part of loci, and respectively adds the three pairs of public primers to the 5' end of the MiniSTR primers to obtain 24 additional primers; the use of the inventive kit can simultaneously amplify 12 X chromosome STR loci at a single-tube, avoids the competition between these primers and the formation of heterozygosity dimers, increases the amplification efficiency of each locus, wherein, the length of amplification products can be less than the 280bp, and has a high sensitivity (as low as 30pg), a higher STR parting success rate can be obtained and the amplification efficiency of medical examiner DNA degradation samples can be improved. The inventive kit has advantages of high sensitivity, high specificity, high detection efficiency, low preparation cost and the like.

The invention aims to provide an excrement preserving fluid which is applied to excrement preservation. The excrement preserving fluid can preserve an excrement sample for a long time at normal temperature, can effectively inhibit DNA degradation and cell damage in the excrement sample, maintains cell morphology, and has a good inhibiting effect on the activity of degradation enzymes and microbes.The invention also provides a preparation method of the excrement preserving fluid. The excrement preserving fluid prepared by the preparation method is used for preserving excrement. The excrement preserving fluid comprises 10-500 mmol/L of a chelating agent, 1-100 g/L of a bacteriostatic agent, 1-10 g/L of an ionic strength maintaining agent, 1-50% (v/v) of a cell protective agent and 1-50 g/Lof a denaturing agent.

The invention relates to the technical field of biology, and discloses a method for detecting the nucleic acid mass of a sample, which comprises the following steps: adding internal control nucleic acid molecules with different lengths into a sample; carrying out specific amplification on conserved sequences with different lengths of nucleic acids to be detected in the sample and the internal control nucleic acid molecules in the same reaction system; detecting the amplification results; comparing the quantity of the conserved sequences and the quantity of the internal control nucleic acid molecules; and analyzing. Preferably, the invention adopts the real-time fluorescent quantitative PCR (Polymerase Chain Reaction) technology in the amplification and detection steps. The invention also provides a kit for detecting the nucleic acid mass. By detecting DNA (deoxyribonucleic acid) segments with different lengths to determine the DNA degradation degree in the sample, the method disclosedby the invention can accurately reflect the incidence of the sample inhibitor, and can be widely used in the fields of medicolegal examination, microbiological examination and food safety.

The invention discloses a rapid separation and detection kit and method for fragmented crosslinked DNA. The kit includes a reagent for decrosslinking and separation extraction of fragmented DNA, and the reagent is Chelex 100. The kit can further include a protein degradation reagent, a DNA ladder marker, a sample loading buffer solution and/or an RNA degradation reagent. Chelex 100 can integrate multivalent metal ions, has high metal ion selectivity and binding force, can separate DNA and prevent DNA degradation. The rapid separation and detection method for fragmented crosslinked DNA can determine whether a to-be-detected sample needs further ultrasound or is used for a next step precipitation experiment according to the effect of rapid quality control ultrasound fragmentation, or can be used for ultrasound optimization of a plurality of to-be-detected samples so as to select optimum conditions. The kit and the method provided by the invention can be used for rapid detection of chromatin ultrasound fragmented sample quality in chromatin immunoprecipitation assay (ChIP) and other technologies, and can greatly improve the success rate of ChIP.

The invention belongs to the technical field of aquatic animal molecular biology DNA sample preparation, and concretely relates to a method for extracting DNA from a shrimp shell of procambarus clarkia. The method comprises the following steps: cutting the shrimp shell of the procambarus clarkii immersed in an ethanol solution, adding a proper amount of a tissue lysate, EDTA, dithiothreitol, protease K and the like in a centrifuge tube, carrying out processes of water-bath cracking, ammonium acetate extraction and the like to obtain the total DNA of procambarus clarkia. The method of the invention has the advantages that the operation is simple and convenient, the used reagent enables small toxicity, less injury on the experimental animals when sampling is carried out, the samples are easy to be preserved for long-term, the degradation degree of the extracted DNA is lower than the degradation degree of the extracted DNA from the shrimp tail muscle. The prepared DNA can be used for diversity analysis of procambarus clarkii population genetics and the relative molecular biology application.

The invention relates to a dry plant tissue treatment method applied to flow cytometry, belonging to the technical field of biological analysis and aiming at solving the problem that only a fresh sample can be analyzed in the prior art. The treatment method comprises the following steps: performing cell nucleus extraction, staining and analyzing, wherein a cell nucleus extracting solution used by cell nucleus extraction comprises the following components: 12-18mM of Tris, 1-3Mm of Na2EDTA, 0.2-0.3mM of spermine tetrahydrochloride, 70-90mM of KCl, 10-25mM of NaCl, 10-20mM of beta-mercaptoethanol and 0.2-0.5 percent of Triton X-100, and the pH value is 6.5-7.0. The method has the effects of preventing cell nucleus DNA degradation, improving the stability of cell nucleus and lowering probability of oxidation of cell nucleus, and can be applied to various dry plant tissues, and the application range is widened.

A method for extractING genomic DNA of Lonicera japonica Maxim belongs to field of molecular biology. The method mainly comprises the following steps: firstly, cell walls and cell membrane are brokenso that DNA is fully released into buff; secondly, the interference of protein, polysaccharide, pigment and other impurities was eliminated; finally, DNA degradation is prevented. The sample was treated with SET nucleus separation buffer, which could separate the nucleus from the secondary substances such as polysaccharides and polyphenols in the supernatant, PVP added in the grinding process andbeta-Mercaptoethanol, can effectively prevent the oxidation of polyphenols, chloroform/isoamyl alcohol extraction, the addition of diluted CTAB to remove polysaccharides. The leaves of Caprifoliaceaeplants are rich in carbohydrates and polyphenols, These substances not only affect the extraction of DNA, but also affect the activity of Tag enzyme in PCR. By this method, DNA with high yield and good quality can be obtained. DNA electrophoretic bands are clear and bright, and there is no tail-trailing phenomenon, which can meet the further research at molecular level.

The invention relates to dsRNA in an organism or tissue and a method for extracting the dsRNA. The method comprises the following steps: pre-treating, centrifuging to obtain supernate, carrying out chromatography on the supernate, carrying out segmented elution, and collecting eluent for post-treatment. According to the method, organic reagent treatment and cellulose column chromatography are combined, firstly, an organism or tissue is treated to be broken, and nucleic acid substances are released into a liquid phase; and by means of reversible adsorption of filler in cellulose column chromatography on liquid-phase medium-concentration nucleic acid substances, dsRNA and other nucleic acid substances can be effectively separated through segmented elution, especially interference of DNA degradation substances can be remarkably reduced, and the purity of the final product dsRNA can be improved.

The invention discloses a preparation method of a deep sea fish extract capable of prolonging the brain cell life. The preparation method comprises the following steps: step-by-step enzymatic hydrolysis, micro-filtration, secondary ultra-filtration and nano-filtration, macro-porous resin adsorption and eluting, freezing and drying. The preparation method disclosed by the invention has the benefits that the preparation method is simple, detailed data is provided for each step, the reproducibility is strong, and the suitability for large-scale production is realized; as a large number of restriction enzyme cutting sites of porphyra yezoensis proteases is on deep sea fish proteins, after enzymatic hydrolysis, peptide chains of different lengths can be obtained, and the deep sea fish extract capable of prolonging the brain cell life can be obtained through enzymatic hydrolysis with flavor proteinase. The obtained deep sea fish extract can inhibit the production of endogenous endonucleases and delay the DNA degradation of cell chromosomes, thereby delaying the expression of apoptosis procedures in neuronal cells and effectively prolonging the brain cell life.

The present invention provides a multiplex PCR kit with improved STR analysis success rate by introducing mini-STRs at 7 gene loci including a mini-STR at SE33 locus, which has high gene identification sensitivity, into a human genotype profile identification technique, as well as a method for identification of human genotype profiles using the same. According to the present invention, the STR analysis success rate is improved by identifying an STR at a locus that cannot be discriminated depending on DNA degradation level, thereby offering a lot of DNA information. Further, the present invention may contribute to more efficient DNA identification such as extension of database record, increase in identity determination success rate, etc. Still further, clues for reconstruction of a crime scene may be offered while improving reliability of forensic investigation results, simultaneously, thereby contributing to solving the crime.

The invention provides an RNA analyzing method of paraffine section tissue. The analyzing method comprises the following steps of performing DNA degradation on the paraffine section tissue, and extracting RNA of samples; preparing a paraffine section sample nucleic acid library, and sequencing sample RNA; performing quality control on the sample data obtained by sequencing; comparing the sample data after quality control with a reference genome, and performing quality control on comparing results; and performing transcriptome assembling and transcript quantifying on the sample data after quality control of comparing results, and performing quantification analysis, gene difference expression analysis and fusion gene analysis on gene expression. The invention provides an index and detectionmethod for completely assessing RNA quality of the paraffine section tissue, so that RNA of the paraffine section tissue can be comprehensively assessed, and the assessment results are accurate and effective. An effective reference basis is provided for subsequent analysis accuracy.

The invention relates to application of an acellular allogeneic dermal matrix in penile augmentation. In order to adapt to the penile augmentation and provide an appropriate built-in biological sleevematerial, the novel acellular allogeneic dermal matrix material is prepared by the coordination of multiple steps such as enzyme treatment, surfactant ultrasonic treatment and DNA degradation treatment and prepared into the built-in biological sleeve which is used for treating premature ejaculation and small and short penis. The acellular allogeneic dermal matrix or built-in biological sleeve isused for penile augmentation or lengthening or dorsal nerve isolation surgery while dorsal nerve cutting is not needed, and psychogenic erectile dysfunction caused by the fact that a patient worries about the dorsal nerve cutting is avoided.

The invention discloses utilization of pichia pastoris to produce high-specific activity high temperature- resistant phytase, adopts many isogenous phytase genes, using DNA enzyme to make partial enzyme mediation, recovering all the DNA degraded fragments, in vitro rearranging DNA molecules, making enzyme cutting on all the rearranged DNA molecules, then composing them in an expression carrier, electrically shocking them in Escherichia coli, screening mutant phytase gene by phytase expression and activity, and finally obtaining high-specific activity high temperature-resistant phytase gene Phy XH, which is constructed into phytase gene expression carrier pPhy XH, electrically shocking and transferring in pichia pastoris, and selecting recombinant high-phytase expression pichia pastoris.

The present invention is based on the discovery of sensitive and specific methylation detection by a) controlling excessive DNA degradation prior to conversion by incubating DNA conversion reagent (e.g. bisulfite reagent) directly with a nucleic acid containing sample without requiring prior nucleic acid purification from the sample and without requiring prior nucleic acid denaturation at elevated temperatures of 98° C. and, b) optimizing bisulfite removal by controlling the pumping rate flow of the bisulfite treated sample over an extraction membrane inside an automated system.

The invention relates to an on-site collection method of a karst cave water environment DNA sample, which comprises the following steps: 1, collecting water from a karst cave water environment DNA detection point by using a Bailer tube, and putting the collected water sample into a disposable plastic basin for later use; 2, preliminarily filtering the DNA water sample in the karst cave environment collected in the step 1, and removing large-particle impurities, 3, taking a disposable syringe, sucking the preliminarily filtered water sample, connecting the water sample to a membrane-replaceable needle type filter loaded with a glass fiber membrane, manually extruding the syringe at a constant speed to enable the water sample to pass through the membrane-replaceable needle type filter, and then discharging the water sample, putting the replaced filter membrane into a centrifugal tube filled with anhydrous alcohol, and storing at low temperature. According to the method, the DNA sample in the karst cave water environment can be collected on site, the problems of DNA degradation, cross contamination and the like when a water sample is remotely transported to a laboratory for vacuum filtration are solved, and the collection method is low in cost, simple and convenient to operate and high in accuracy of the collected sample.