8 results about "DNA - Deoxyribonucleic acid" patented technology

Linear DNA with improved resistance against exonucleases and methods for its production. The present invention relates to methods for producing a linear deoxyribonucleic acid (DNA) product (e.g., a closed linear DNA product) with improved resistance to nuclease digestion. The present invention relates to methods comprising the steps of: (a) contacting a double-stranded DNA molecule with an endonuclease, a ligase, and first and second terminal adaptor molecules and intermediate adaptor molecules to form a single contiguous aqueous volume; and (b) incubating the single contiguous aqueous volume to generate a linear DNA product (e.g., a closed linear DNA product). The present invention also relates to linear deoxyribonucleic acid (DNA) products (e.g., a closed linear DNA product) with improved resistance to nuclease digestion and uses thereof.

The application discloses a kind of nanoparticles for removing lung mucus and its preparation method and application, it is related to the field of biological medicine.The nanoparticles of the application are composed of inner core and shell coated on the surface of the inner core, wherein the inner core contains citric acid and photoluminescent polymer-aliphatic polyester copolymer;The shell contains deoxyribonuclease and hydrophilic polymer.The nanoparticles provided by the application have excellent biocompatibility and multifunctional integration characteristics, which realizes effective penetration of lung mucus barrier, specific degradation of DNA network, down-regulation of pro-inflammatory factors and inhibition of mucus production in sequence through cascade response mechanism, breaking through the limitations of traditional single therapy.In addition, the in vivo experimental results show that it can significantly reduce the thickness of lung mucus and the protein concentration of lavage fluid, and effectively relieve airway obstruction, and can be used for removing lung mucus.

The application provides a PDRN and an extraction method and application thereof, and belongs to the technical field of PDRN extraction. The extraction method of the PDRN comprises the following steps: subjecting plant tissues to stress treatment, so that the cells are in an irreversible damage state; subjecting the plant tissues subjected to the stress treatment to incubation treatment, so that DNA is selectively partially degraded under the action of endogenous deoxyribonuclease; and subjecting the plant tissues subjected to the incubation treatment to crushing treatment and extraction and purification treatment, to obtain the PDRN. The extraction method selectively degrades DNA under mild conditions by using endogenous enzymes (such as DNase) of plants, and has the advantages of high yield, high efficiency, low cost and green environmental protection; meanwhile, the PDRN extracted by the extraction method also has the advantages of high purity, high physiological activity and high safety.

The invention relates to methods for producing a linear deoxyribonucleic acid (DNA) product with enhanced resistance to nuclease digestion. The linear DNA product may be a closed linear DNA product, a linear DNA product comprising nuclease-resistant nucleotides, or a partially closed DNA product.

A thermal cycling method and associated device is described. The method is for carrying out a polymerase chain reaction (PCR) process to amplify deoxyribonucleic acid (DNA), and the method includes: pre-heating a series of blocks to respective temperatures that correspond to different respective heating stages in a PCR process, in which each block of the series of blocks defines a respective heat transfer surface, in which the series of blocks define a sequence of positions along a path, with each position defined by a respective heat transfer surface of a respective block; and moving a PCR reaction vessel, which contains deoxyribonucleic acid (DNA) and PCR reagents, along the path into and out of each respective position in the sequence of positions according to a schedule, in which, at each respective position the PCR reaction vessel is in thermal contact with the respective heat transfer surface to equilibrate a temperature of the PCR reaction vessel to a target temperature that corresponds to a respective heating stage in the PCR process.

FIELD: biotechnology.SUBSTANCE: used in diagnostic and research laboratories. A method for producing rod-shaped magnetite particles for isolating deoxyribonucleic acid (DNA) from whole blood is proposed, which includes producing Fe3O4 magnetite rods. At the first stage, particles of akagenite β-FeOOH are formed by hydrolysis of 0.57 M aqueous solution of FeCl3 at a temperature of 120–125 °C for 3 h. After completion of the reaction, the suspension is cooled to room temperature, the precipitate is separated by centrifugation at 10000 g for 10 min, washed with deionized water and ethanol and dried at 60 °C throughout the day. The resulting akagenite particles are dispersed in 20 ml of ethylene glycol using ultrasonic treatment at 100 W for 15 minutes. The resulting suspension is placed in an autoclave and subjected to hydrothermal treatment at 200 °C for 8 hours with the formation of the magnetite phase Fe3O4. Magnetite particles are separated with a magnet, washed successively with water and ethanol and dried at 60 °C within 24 hours. Then, a SiO2 shell is formed by dispersing a 50 mg sample of dried magnetite rods in 5 ml of deionized water. Dispersion is carried out in five cycles, each of which includes stirring at 300 rpm for 10 min and ultrasonic treatment at 45 W for 3 min. Isopropanol is added to the resulting suspension at a rate of 15 ml of isopropanol for every 5 ml of water, after which the mixture is stirred for 20 min at 300 rpm. Then, while stirring, 0.5 ml of a 25% NH4OH solution and 0.5 ml of tetraethoxysilane are added to the aqueous alcohol dispersion of particles for every 50 mg of rods. The formation of the SiO2 shell is carried out at room temperature for 20 hours with constant stirring. After incubation, the particles are purified by magnetic decantation with deionized water at least five times. The process of forming a silicon dioxide shell is repeated twice, and the purified rod-shaped particles of Fe3O4@SiO2 are dispersed in a 5% solution of polyethylene glycol with a molecular weight of 4000 Da. Fe3O4@SiO2-NH2 particles can also be obtained.EFFECT: increasinng the quantity and improving the purity of DNA isolated from whole blood by using magnetic particles with increased specific surface area and sorption capacity.2 cl, 12 dwg, 2 tbl, 3 ex

The application belongs to the technical field of biological medicine, and particularly relates to a thymus tissue dissociation reagent, a kit and application thereof in obtaining thymus epithelial cells. The thymus tissue dissociation reagent at least comprises collagenase D, dispersinase II, deoxyribonuclease I, dissociation enzyme and a dissolving reagent; and collagenase II and / or collagenase IV and / or trypsin. The cell survival rate of the thymus tissue dissociation reagent after dissociating the thymus tissue is maintained at a high level of 95.7% to 99.6%, which is significantly higher than that of the prior art; and after sorting, the number of thymus epithelial cells enriched and obtained from each gram of thymus tissue is 1.38e 5 ~1.06e 6 , and the success rate of enriching and obtaining thymus epithelial cells is as high as 95%, which is significantly higher than that of the prior art; and the proportion of epithelial stem cells in the thymus epithelial cells is 65.7%, which is significantly higher than that of the prior art.

Systems and methods are provided that can keep adoptively transferred macrophages in solid tumors in the tumoricidal MI phenotype. Microparticles containing poly(N-isopropylacrylamide) (PNIPAM) and a multilayered structure made of deoxyribonucleic acid (DNA) and a polycation (PC) can be produced by depositing a multilayer of DNA and a PC and a layer of PNIPAM on a stamp bearing micropillars, followed by printing the disk-shaped structures on a substrate. The DNA / PC multilayer can be delivered into the cytoplasm of the macrophages and / or monocytes by incubating the microparticles with macrophages and / or monocytes, briefly exposing the cells to a cold temperature, and continuing to culture the cells. The microparticles can be phagocytosed by the macrophages and / or monocytes during initial incubation. The brief exposure to the cold temperature can induce phagosomal rupture and release of the DNA / PC multilayer into the cytoplasm of the cells.