90results about How to "Low cytotoxicity" patented technology

The invention belongs to the technical field of biology, and particularly relates to antibacterial peptide based on large yellow croaker CXCL8 protein and application of the antibacterial peptide. The preparation method comprises the following steps: by taking a large yellow croaker CXCL8 protein as a template, intercepting a linear polypeptide of 13 amino acids, and carrying out carboxyl terminal amidation modification, so as to obtain the antibacterial peptide AVV13N, and the amino acid sequence of the antibacterial peptide AVV13N is Ala-Arg-Trp-Val-Arg-Arg-Val-Leu-Lys-Lys-Met-Val-NH2; the antibacterial peptide AVK13N is obtained by interchanging lysine at the 11th site and valine at the 13th site in an amino acid sequence of the antibacterial peptide AVV13N, and the amino acid sequence of the antibacterial peptide AVK13N is Ala-Arg-Trp-Val-Arg-Arg-Val-Leu-Lys-Lys-Val-Met-Lys-NH2. The molecular weights of the antibacterial peptides AVV13N and AVK13N are both 1669.12 Da, the isoelectric points of the antibacterial peptides AVV13N and AVK13N are both 12.44, and the antibacterial peptides AVV13N and AVK13N are both alkaline polypeptides. The antibacterial peptides AVV13N and AVK13N have broad-spectrum bactericidal activity and can be used for specifically killing gram-positive bacteria and gram-negative bacteria. In addition, the antibacterial peptides AVV13N and AVK13N have relatively weak hemolytic activity, relatively low cytotoxicity and good temperature stability, pH value stability and salt ion stability. The antibacterial peptides AVV13N and AVK13N provided by the invention can replace antibiotics and are applied to prevention and treatment of bacterial diseases.

The invention discloses temperature-sensitive antibacterial hydrogel based on ultra-small-particle-size copper nanoparticles and a preparation method of the temperature-sensitive antibacterial hydrogel, and relates to the technical field of biomedical materials. The preparation method of the temperature-sensitive antibacterial hydrogel comprises the step of uniformly mixing the gel matrix, the stabilizer, the pH buffer solution and the ultra-small-particle-size copper nanoparticles to prepare the temperature-sensitive antibacterial hydrogel. The preparation method of the copper nanoparticles with the ultra-small particle size comprises the following steps that lactoferrin is dissolved in water, copper sulfate pentahydrate is added, an alkali solution is added to adjust the pH of the solution to be 8-14, then a reducing agent is added for a reaction, dialysis and drying treatment are conducted, and the copper nanoparticles with the ultra-small particle size are obtained. The hydrogel has good injectability, can release the copper nanoparticles under specific conditions and rapidly sterilize, in addition, the hydrogel is convenient to synthesize and simple to operate, has good biocompatibility, shows relatively low cytotoxicity to cells, and has relatively great application potential in the process of treating skin wound infection.

The present invention discloses an antimicrobial peptide and its application, wherein the antimicrobial peptide comprises one or more of an antimicrobial peptide PFK having an amino acid sequence as shown in SEQ ID NO: 1, an antimicrobial peptide PVK having an amino acid sequence as shown in SEQ ID NO: 2, and an antimicrobial peptide PIK having an amino acid sequence as shown in SEQ ID NO: 3. The antimicrobial peptides PFK, PVK and PIK of the present invention have antimicrobial effects on Porphyromonas gingivalis, Streptococcus mutans, Acinetobacter baumannii, Escherichia coli and Staphylococcus aureus, and the antimicrobial peptides PFK, PVK and PIK have low hemolytic activity and low cytotoxicity, and can be used to prepare biological antimicrobial preparations, anti-infective drugs or oral products.

The invention discloses a membrane-rupturing antibacterial peptide and application thereof. On the basis of an artificial intelligence screening method, a membrane-rupturing antibacterial peptide KLAKLLKLLLWAQNELDQKK is identified from a proteome of toads, the membrane-rupturing antibacterial peptide has three positive charges, and 50% of amino acid is hydrophobic amino acid. Through experimental tests, the antibacterial peptide can inhibit the growth of 10 different strains including gram negative strains and gram positive strains; meanwhile, the semi-maximum hemolysis concentration and the semi-maximum cytotoxicity concentration of the antibacterial peptide are both greater than 128 mu g / mL, and the antibacterial peptide has good biological safety. The antibacterial peptide plays an antibacterial role by destroying cell membranes, has the characteristic that the drug resistance of bacteria is not easily caused, and is an ideal development object of antibacterial drugs and antibacterial products such as disinfectants, detergents and feed additives.

The invention relates to the technical field of microbial probiotic preparations, in particular to a sodium alginate multifunctional composite microsphere as well as a preparation method and application thereof. The sodium alginate multifunctional composite microspheres are obtained by dissolving the carbohydrate vesicles, the traditional Chinese medicine nanoparticles and the probiotics in a sodium alginate solution and then dropwise adding the solution into a calcium chloride solution through an ionic cross-linking effect. According to the invention, the amphiphilic xylooligosaccharide-cystamine derivative with H2S response is synthesized through a click reaction on the basis of prebiotic xylooligosaccharide. And the amphipathic saccharide vesicles are obtained through self-assembly by virtue of hydrophilic and hydrophobic effects. Sanguinarine iodide prepared by purification, separation and reflux and baicalin are self-assembled in an aqueous solution through a non-covalent bond, and the traditional Chinese medicine nanoparticles are prepared through ultrasonic treatment. An in-vitro simulated release experiment proves that the sodium alginate multifunctional composite microsphere is relatively low in release rate under an acidic condition, so that substances are favorably delivered to intestinal tracts; and the release of encapsulated substances can be better realized in neutral and alkaline environments.

The invention discloses an oligopeptide for treating neonatal bacterial meningitis and a preparation method of the oligopeptide, and belongs to the technical field of biological medicines. The invention successfully designs and prepares small molecular mimic peptides capable of effectively blocking escherichia coli from invading into the brain based on a lactam cyclization technology, the small molecular mimic peptides are named as EC-MP-1 and EC-MP-2, and animal level research proves that the mimic peptides disclosed by the invention can inhibit the invasion of E44 escherichia coli to HBMEC; cell and molecular level researches prove that the mimic peptide disclosed by the invention can play an effective therapeutic role. A new thought is provided for prevention and treatment of neonatal meningitis, and reliable scientific data is accumulated for subsequent development and clinical application of micromolecule polypeptide drugs.

The application provides a method for inducing poly-podophylli rhizoma by using clump buds, comprising the following steps: S1, cutting stem segments from a podophylli rhizoma mother plant, soaking and cleaning to obtain explants; S2, disinfecting and cleaning the explants, inoculating into a clump bud induction medium to obtain podophylli rhizoma clump buds; S3, inoculating the clump buds into doubling liquid I, washing with a liquid clump bud induction medium after culture, and then transferring into doubling liquid II; S4, taking out the clump buds, cleaning, inoculating into a clump bud induction medium, and then inoculating into a bud proliferation medium; S5, waiting until 1-2 cm, screening out potential mutant strains through phenotypes, inoculating into the bud proliferation medium for subculture, and obtaining mutant plants; and S6, rooting culture of the mutant plants, and after root systems grow, planting and raising seedlings, and then poly-podophylli rhizoma plants are obtained. In the research, suitable concentration of colchicine is used for induction treatment twice, and through stage concentration switching and intermittent recovery strategies, the poly-ploid induction efficiency and explant survival are effectively considered.

A ferritin fusion protein according to an embodiment includes a cancer-targeting peptide and a peptide to be cleaved in a cancer cell linked to an outer surface thereof. The ferritin fusion protein may enable efficient cancer-targeting treatment by releasing an anticancer drug specifically in a cancer cell, has excellent anticancer efficacy, and can effectively reduce toxicity to a normal cell, thereby minimizing side effects of anticancer treatment.

The present application provides a kind of polypeptide, wherein the polypeptide has the amino acid sequence as shown in SEQ ID NO.1 or the amino acid sequence as shown in SEQ ID NO.2;The inventors of the present application prepare a kind of high activity peptide mixture by the process of pearl powder enzymolysis, ultrafiltration, freeze-drying etc., the high activity peptide mixture has the efficacy of whitening, anti-aging etc.On this basis, the present application obtains two polypeptides SEQ ID NO.1, SEQ ID NO.2, the amino acid sequence of the SEQ ID NO.1 is TKLDHAVT, the amino acid sequence of the SEQ ID NO.2 is VPGF;In another embodiment of the present application, the inventors of the present application obtain polypeptide SEQ ID NO.1, SEQ ID NO.2 by self-synthesis method.In some specific embodiments of the present application, the inventors of the present application find that the aforementioned two polypeptides SEQ ID NO.1, SEQ ID NO.2 have significant melanin inhibitory activity.

The present invention provides a charge-reversible phospholipid that is not positively charged at a pH of the body fluid (typically in the neutral range) and has low cytotoxicity. The present invention provides a phospholipid represented by formula (1): wherein m represents a natural number of 9 to 25, n represents a natural number of 10 to 15, X1, X2, and X3 are the same or different and each represent H or OH, and R1 represents the following formula (i) or (ii): wherein p represents 1 or 2, q represents 1 or 2, and r represents an integer of 1 to 4; or wherein s represents an integer of 1 to 3, and R2 represents a hydrogen atom or a hydrocarbon group.

The invention relates to the technical field of polymer materials, and particularly provides a biocompatible polymer material as well as a preparation method and application thereof. The molecular structure of the biocompatible polymer material contains at least one first block and at least one second block, the first blocks and the second blocks are arranged alternately, and the adjacent first blocks and second blocks are connected through carbamate bonds; the first block is formed by aliphatic polyester diol and / or alicyclic polyester diol, and the number-average molecular weight of the first block is 1000-10000; the second block is formed by aliphatic polyether glycol, and the number-average molecular weight of the second block is 200-2000. The polyurethane material disclosed by the invention has the characteristic of relatively high mechanical strength, and the cytotoxicity of the polyurethane material is relatively low after the low-molecular-weight monohydric alcohol is further adopted for blocking. The polyurethane material can be used for biological tissue engineering or wound dressing.

The application discloses a drainage bag with an antibacterial functional layer and a preparation process thereof, and relates to the technical field of medical materials, and comprises the following steps: adding modified montmorillonite into N, N'-dimethylacetamide, uniformly mixing through ultrasonic, adding a polyurethane film, ultrasonic immersion for 60-120 min, drying, and obtaining a drainage bag substrate; adding polylactic acid into N, N-dimethylformamide, uniformly stirring and mixing, adding modified nano zinc oxide, uniformly mixing through ultrasonic, and then performing electrospinning to obtain an antibacterial coating fiber film; placing the antibacterial coating fiber film on the inner side surface of the drainage bag substrate, high-frequency heat sealing, assembling, and obtaining the drainage bag.

The invention belongs to the technical field of food fresh-keeping materials, and particularly relates to an aerogel type composite fresh-keeping pad as well as a preparation method and application thereof. The preparation method of the aerogel type composite fresh-keeping pad comprises the following steps: S1, mixing polyethylene glycol, oxalic acid and polyacrylic acid, and stirring at 70-80 DEG C to obtain a eutectic solvent; the method comprises the following steps: mixing a biomass raw material with a deep eutectic solvent, extracting, and filtering to obtain solid residues; s2, mixing the obtained solid residues with water, performing high-pressure homogenization treatment, mixing the obtained cellulose-containing suspension with a gelatin solution and a cross-linking agent, pouring the obtained mixed solution into a forming mold, performing freeze-drying treatment, and taking out to obtain the aerogel type composite fresh-keeping pad. The aerogel type composite fresh-keeping pad prepared by the method disclosed by the invention has good mechanical property, water absorption and antibacterial activity, and shows an excellent fresh-keeping effect in fresh-keeping of fish slices.

This invention provides an interleukin-31 (IL-31) production inhibitor and a pharmaceutical composition comprising the inhibitor. The invention also provides a novel compound useful as an active ingredient for an IL-31 production inhibitor. These comprise a compound represented by the following formula (1) or a salt thereof as an active ingredient: wherein A is a -NH-N=C(R1)- group, a divalent N-containing 5-membered heterocyclic group, or a -NH-CO- group, wherein R1 is a hydrogen atom or a C1-4 alkyl group, B is the same or different and is a C1-6 alkyl group optionally having one hydroxyl group, a mono or di(C1-6 alkyl)amino group optionally having one hydroxyl group, a halogen atom, a halo C1-6 alkyl group, a C2-6 alkynylene group, or a carboxy group, wherein at least one C1-6 alkyl group in the mono or di (C1-6 alkyl) amino group is optionally attached to a carbon atom adjacent to a carbon atom in the phenyl group to which it is attached, to form a 5- to 6-membered ring, and n is an integer of 1 to 5.

The application discloses an intrauterine postoperative anti-adhesion membrane, a preparation method thereof and a delivery device. The anti-adhesion membrane is a two-phase system composed of a natural polymer hydrogel outer layer and an inner layer of a specific block copolymer physically blended, forming a two-phase structure with gradient hydration function. The inner layer polymer is the core, covering ABA, AB or BAB type block structure, wherein the hydrophilic segment B can be selected from PEG, PEO, PNVP or PAA, and the hydrophobic segment A can be selected from PLA, PDLA, PGA, PCL, PTMC or a copolymer thereof. The total thickness of the material is 100-1000 microns, which can swell in body fluid and completely degrade within 7-30 days. The morphology is specially designed to accurately match the anatomical section of the target tissue. The application effectively isolates the wound surface and is mainly suitable for postoperative tissue adhesion prevention, uterine cavity repair, hemostasis and local drug release.

The invention relates to the technical field of medical treatment and beauty treatment, in particular to a solution for injection and a preparation method thereof. According to the injection solution disclosed by the invention, the cross-linked sodium hyaluronate, the vitamin B, the active peptide, the nicotinamide, the amino acid, the buffer solution and the water for injection are taken as raw materials, so that the injection solution is endowed with relatively good enzyme stability, is not easy to quickly decompose in vivo and is non-toxic; functional raw materials such as active peptide and nicotinamide are used, so that the injection solution has excellent anti-aging and melanin inhibition effects.

This invention discloses a weak force sensor based on a teardrop-shaped micro / nano optical fiber and its fabrication method. The sensor comprises a biconical micro / nano optical fiber, a single-conical optical fiber, a quartz capillary tube, and a PDMS microsphere. The biconical micro / nano optical fiber is symmetrically bent, with the central waist region fiber forming a teardrop-shaped ring. The two ends of the teardrop-shaped micro / nano optical fiber ring are sequentially connected to portions of the waist region fiber, a transition region fiber, and a standard fiber. This invention utilizes the sensitive self-sensing capability of micro / nano optical fibers to achieve integrated signal input and output, greatly simplifying the measurement feedback mechanism of the sensing system and reducing overall cost. Furthermore, it is simple and intuitive to operate, reducing the technical requirements for operators. In terms of sensor fabrication, the main raw materials are standard optical fiber and quartz capillary tube, both of which are extremely low-cost. Therefore, this micro / nano optical fiber sensor exhibits significant cost-effectiveness.

The invention belongs to the technical field of drugs for treating psoriasis, and particularly relates to a microminiature platinum cluster enzyme as well as a preparation method and application thereof. The microminiature platinum cluster enzyme comprises a platinum metal core and a cyclodextrin ligand, and the preparation method of the microminiature platinum cluster enzyme comprises the following steps: adding a Pt precursor solution into a sulfydryl-cyclodextrin solution, mixing, adding a reducing agent, and reacting to obtain the microminiature platinum cluster enzyme. The preparation method disclosed by the invention is simple and feasible, and the microminiature platinum cluster enzyme prepared by the method has the remarkable advantages of safety, effectiveness and economy in treatment and prevention of psoriasis.

The present invention belongs to the field of new biomedical technology applications, and specifically relates to a targeted polypeptide and a radioactive tracer for brain glioma. The amino acid sequence of the polypeptide is: KINWKFRLRY, Lysine-Isoleucine-Asparagine-Tryptophan-Lysine-Phenylalanine-Arginine-Leucine-Arginine-Tyr, Lys-Ile-Asn-Trp-Lys-Phe-Arg-Leu-Arg-Tyr. The radioactive tracer is represented by: 68 Ga‑DOTA‑KINW, where, 68 Ga is a radionuclide, DOTA is a chelating agent, and KINW is a polypeptide targeting the NPY1R receptor protein. The present invention uses mutation scanning and molecular docking technology to screen and modify a targeting polypeptide that specifically binds to NPY1R. Compared with the sequences reported previously, KINW has more binding sites to NPY1R and less cytotoxicity. KINW can cross the blood-brain barrier and 68 Ga chelation can image in situ brain glioma; the radioactive tracer prepared by the invention is used as an imaging drug for brain glioma, and has the characteristics of long imaging time, easy preparation and the like.

The invention belongs to the technical field of medicines, and particularly relates to a dihydropteridine-6 (5H)-ketone skeleton compound as well as a preparation method and application thereof. The dihydropteridine-6 (5H)-ketone skeleton compound disclosed by the invention is an HIV-1 (Human Immunodeficiency Virus-1) non-nucleoside reverse transcriptase inhibitor; the invention also comprises pharmaceutical salts, hydrates, solvates, polycrystals or co-crystals of the compounds, precursors and derivatives with the same biological functions of the compounds, a preparation method of the compounds and application of a composition containing one or more of the compounds in preparation of related drugs for treating AIDS and the like. The result of an in-vitro cellular level anti-HIV-1 activity experiment shows that the micromolecule has relatively strong anti-HIV-1 biological activity, can remarkably inhibit virus replication in MT-4 cells infected by HIV-1 viruses, and has relatively low cytotoxicity.

The invention relates to the technical field of biomedical materials, in particular to a nano assembly for releasing NO through red light triggering and a preparation method and application of the nano assembly. The nano assembly is prepared from an amphiphilic block polymer with a polyethylene glycol hydrophilic end and a hydrophobic segment containing NO donor molecules and photocatalyst molecules through a hydrophilic and hydrophobic self-assembly forming method. Photocatalyst molecules in the amphiphilic block polymer are excited under irradiation of red light, decomposition of NO donor molecules can be triggered through an electron transfer process, and space-time controllable adjustment of NO release is achieved. The nano assembly has the red light response characteristic, excellent biological safety and antibacterial property, and has a wide application prospect in the aspects of antibiosis, anti-inflammation and the like. In addition, the red light has the characteristics of large tissue penetration depth and low phototoxicity, so that the problem that the penetration depth of the traditional ultraviolet light or blue light response NO donor molecular monomer is limited is effectively solved.

The present invention discloses the application of rubusoside in the preparation of a drug for preventing and treating osteoporosis. The present invention finds that rubusoside as the only active ingredient can promote the osteogenic differentiation of MC3T3-E1 cells, promote the expression of ALP, BMP-2, COL, and RUNX2 mRNA, and promote the expression of ALP, BMP-2, COL, and RUNX2 proteins in MC3T3-E1 cells; under H2O2 damage conditions, rubusoside pretreatment can protect MC3T3-E1 cells from the decrease in activity and osteogenic ability caused by H2O2 damage; animal experiments show that rubusoside can improve femoral bone density in ovariectomized rats and increase the number and thickness of trabeculae. Therefore, rubusoside can be used to prevent and treat osteoporosis.

The invention discloses a PPD ring-opened derivative, which has a structural formula as shown in a formula 11, 12, 13 or 14, or a pharmaceutically acceptable salt of a compound as shown in the formula 11, 12, 13 or 14. The invention discloses a PPD ring-opening derivative, a preparation method of the PPD ring-opening derivative, and application of the PPD ring-opening derivative and pharmaceutically acceptable salts thereof in preparation of a tumor drug resistance reversal agent / tumor drug sensitizer, or preparation of a tumor drug resistance reversal agent / tumor drug sensitizer containing a pharmaceutically acceptable carrier. The PPD ring-opening derivative disclosed by the invention has lower cytotoxicity and better tumor drug resistance reversal effect, and the effect is obviously superior to that of a positive control drug. The PPD ring-opening derivative disclosed by the invention has relatively high development and application values. # imgabs0 #

This invention relates to the field of in vitro stem cell culture technology, specifically to a culture medium for the proliferation of muscle satellite cells, its culture method, and its application. The culture medium comprises a basal medium, fetal bovine serum, and plant-derived active substances; the plant-derived active substances include at least one selected from apigenin, resveratrol, and quercetin; the volume percentage of fetal bovine serum in the culture medium is 2%-5%. This invention, by adding plant-derived active substances, effectively maintains cell stemness and significantly promotes cell proliferation at low serum concentrations.

The invention discloses a preparation method of red fluorescent carbon dots with lysosome and nucleolus dual-targeting capability in the technical field of nano material synthesis and biological imaging analysis. According to the preparation method, o-phenylenediamine is taken as a carbon source, methanol is taken as a solvent in the presence of rare earth ions, and the red fluorescent carbon dots can be obtained through a solvothermal method reaction in a reaction kettle. The synthesis process is simple, the raw materials are cheap and easy to repeat, and the absolute quantum yield of the purified red fluorescent carbon dots is 11.45%, so that the luminous efficiency is high, and the technical problem that the absolute quantum yield of the red fluorescent carbon dots in the existing bioimaging field is low is solved. The prepared red fluorescent carbon dots have non-exciting light dependence, and the emission wavelength can be extended to 800 nm; the size is small, the particle size distribution is 2.5-5.5 nm, and the average particle size is about 3.75 nm; the oil-water partition coefficient (Log P value) is 0.3-0.4, the water solubility is good, the lysosome and nucleolus targeting specificity is achieved, the photobleaching resistance is high, the biocompatibility is good, and the cytotoxicity is low.

The application discloses an antibacterial peptide derived from the skin of bullfrog and application thereof, and the amino acid sequence of the antibacterial peptide is GSVGPVGPR (as shown in SEQ ID NO:1), and the molecular weight is 824.4504 g / mol. The antibacterial peptide has obvious inhibiting effect on Staphylococcus aureus, and can be used for preparing a medicine for preventing or inhibiting Staphylococcus aureus infection. Meanwhile, the antibacterial peptide and vitamin A have a significant synergistic bactericidal effect on Staphylococcus aureus. The antibacterial peptide and vitamin A can significantly reduce the use concentration of single component, improve the antibacterial efficiency, overcome the bacterial drug resistance problem, and can be used for preparing antibacterial medicines, skin external preparation, medical dressings, feed additives and food preservatives.

The application discloses an antibacterial peptide designed by a generative artificial intelligence framework and targeting gram-negative bacteria and an application thereof, and belongs to the fields of artificial intelligence and biotechnology. The application designs and successfully obtains a novel antibacterial peptide by a generative artificial intelligence framework, the antibacterial peptide targeting gram-negative bacteria and having good antibacterial activity. It is verified by experiments that the antibacterial peptide MTAMP003 has good bacteriostatic capacity on E. coli, S. typhimurium, P. aeruginosa and A. baumannii, exhibits low cytotoxicity on human gastric mucosa epithelium and low hemolyticity on rabbit red blood cells, and has good application prospect and research value.

Disclosed is an antigen targeting, anti-CD16A, and immune effector cell activating trifunctional fusion protein, comprising: a CD16A binding region that specifically binds to CD16A, a tumor-associated antigen (TAA) binding region that specifically binds to a TAA, an IL-15 / IL-15Rα complex formed by combining IL-15 and IL-15Ra, and an Fc domain. A designed tumor-targeting innate immune cell activation molecule, i.e., an anti-TAA, anti-CD 16A, and cytokine IL 15 trifunctional fusion protein targets NK cells to a tumor by simultaneously binding to a TAA on tumor cells and CD16A on NK cells, so that the NK cells release perforin and granzymes to induce apoptosis and cause tumor cell death. The cytokine IL15 expands and maintains the function of the NK cells, stimulates immune cell proliferation, and changes the immune microenviroment of the tumor.

The invention discloses an antibacterial material based on natural polysaccharide as well as a preparation method and application of the antibacterial material. The antibacterial material disclosed by the invention comprises a base material, wherein the base material is modified with dopamine, quaternized polyethyleneimine and hyaluronic acid. According to the invention, QPEI and HA are combined on the surface of PP to prepare the antibacterial material, and the antibacterial material can be used for an anti-fouling antibacterial hernia repair sheet. The invention further provides a preparation method of the antibacterial material. The reaction conditions of the preparation method are mild and not harsh. The hernia repair patch prepared from the antibacterial material is remarkable and lasting in antifouling effect and antibacterial effect, and the modified hernia repair patch is good in biocompatibility and small in cytotoxicity.