49 results about "Cell death rate" patented technology

The invention relates to a buffer solution for suspending animal or human cells and for dissolving biologically active molecules in order to introduce said biologically active molecules into the cells using an electric current and to a method for introducing biologically active molecules into animal or human cells using an electric current and a buffer solution. The inventive buffer solution has a buffering capacity of at least 20 mmol*I⁻¹*pH⁻¹ and an ionic strength of at least 200 mmol*I⁻¹ during a change to the pH value from pH 7 to pH 8 and at a temperature of 25° C. The use of a buffer solution of this type in the corresponding method allows biologically active molecules to be introduced into animal and human cells with a high degree of transfection efficiency and at the same time a low cell mortality. Different cell types, in particular dormant and actively dividing cells of low activity, can be successfully transfected in said buffer solution.

The present invention relates to methods for inducing or promoting caspase-independent apoptosis in a cell, the method comprising exposing to the cell an effective amount of a compound of formula I as described herein. The invention also relates to methods for treating or preventing diseases and disorders by administering to subjects in need thereof an effective amount of a compound of formula I, wherein the compound induces or promotes caspase-independent apoptosis in at least one cell of the subject.

The invention relates to a novel method allowing the transport of DNA and/or other biologically active molecules into the nucleus of eukaryotic cells using electrical current, independently from cell division and with low cell mortality.

The invention relates to an enzymatically decomposed clam oligopeptide having a recovery effect on a non-alcoholic fatty liver disease (NAFLD) cell model. The clam oligopeptide is characterized by comprising an amino acid sequence of Gln Leu Asn Trp Asp. The invention also relates to a preparation method of the enzymatically decomposed clam oligopeptide having the recovery effect on the NAFLD cell model. Compared with the prior art, the following advantages can be achieved: the NAFLD cell model is established by virtue of induction of palmitic acid and the damaged liver cells in a body are simulated sufficiently, and the result indicates that the TG content of the in-vitro NAFLD cell model established 48 hours after induction by 15 micrograms/milliliter palmitic acid increased remarkably in comparison with that of normal liver cells; oil red O staining shows that the number of intracellular lipid droplets of the model group is increased in contrast with that of the cells of a normal group, and the cell mortality rate is low and the repeatability is good, and therefore, the modeling method is simple, convenient and feasible; meanwhile, the enzymatically decomposed clam oligopeptide having the obvious recovery effect on the NAFLD cell model can be separated out from clams.

The invention provides a preparation method for upconversion nanoparticles wrapped by mesoporous silica loading indocyanine green. Upconversion is wrapped by mesoporous silica, and the biosecurity ofthe particles and the loading capacity of the indocyanine green are improved. The size ofthe prepared upconversion nanoparticles wrapped by the mesoporous silica loading the indocyanine green is 80-400 nanometers; after the upconversion nanoparticles wrapped by the mesoporous silica loading the indocyanine green (ICG) are added, the survival rate of cells is within the range of 85-95%; a confocalmicroscope can observe cytophagy of the particles in the cells;after particle addition through laser radiation, the death rate of the cells is within the range of 40-75%.

The invention relates to a method for culturing mesenchymal stem cells through manual simulation of the bone marrow microenvironment. The method comprises the following steps: acquiring the mesenchymal stem cells, and carrying out culture in vitro in a culture medium by adopting a three-dimensional cell culture scaffold, wherein the three-dimensional cell culture scaffold is made of collagen and chitosan or lysine, or the three-dimensional cell culture scaffold is made of collagen, chitosan and glutaraldehyde. According to the method, by adopting chitosan or lysine, or adopting chitosan and glutaraldehyde to modify the collagen scaffold, the mechanical property of the collagen scaffold can be improved; a three-dimensional porous structure of the three-dimensional cell culture scaffold is adopted for maintaining the three-dimensional growing environment in the in-vitro culturing process of the mesenchymal stem cells, so that the bone marrow microenvironment suitable for the growth of the mesenchymal stem cells can be well simulated, and the problem that in the prior art, the single three-dimensional cell culture scaffold is adopted for culturing the mesenchymal stem cells, the mechanical property of the scaffold is poor, so that the cell proliferation rate is low, and the cell death rate is high, is solved.

The invention relates to a novel circuit arrangement for electrotransfection or electrofusion, which enables the transportation of DNA and/or other biologically active molecules to the nucleus of higher eukaryotic cells or the fusion of cells, independent of cell division and with reduced cell mortality.

The invention provides a cell killing efficacy detection method and application thereof. The detection method comprises the following steps: carrying out mixed co-culture on target cells carrying a fluorescence label A and effector cells, then adding a fluorescence label B to label the target cells and the effector cells, and adding a fluorescence label C to carry out dyeing labeling on dead cellsgenerated after co-culture; and then respectively carrying out microscopic imaging on the cells by using different fluorescence channels, identifying and analyzing the cells in the same region in a microscopic image by combining an image synthesis analysis method, and obtaining the cell killing efficacy of effector cells according to an analysis result. Therefore, the detection method can effectively eliminate the interference of impurities and cell debris, can directly obtain a plurality of data such as cell death rate, cell self-injury rate and cell specific killing rate from the image, andhas the advantages of intuitive and visible detection result, high accuracy and high sensitivity.

The invention belongs to the field of sensitizing drugs for tumor chemotherapy, and relates to a new application of sanguinarine, that is, the application in the preparation of sensitizing drugs for improving the curative effect of cisplatin chemotherapy. The sanguinarine described in the invention can be used to prepare a sensitizing drug for improving the curative effect of cisplatin chemotherapy, and can improve the curative effect of cisplatin chemotherapy for tumor cells at a low concentration without toxic or side effects. After treatment with sanguinarine at a concentration without toxic side effects, when combined with cisplatin chemotherapy, compared with cisplatin chemotherapy alone, the cell death rate increased by 100%, almost doubled.

The present invention relates to a vitamin B6-coupled poly(ester amine) (VBPEA) as a gene carrier and a method for preparing the gene carrier. Moreover, the present invention relates to a gene delivery complex comprising a therapeutic gene coupled to the gene carrier and a pharmaceutical formulation for gene therapy, which comprises the gene delivery complex as an active ingredient. In addition, the present invention relates to gene therapy utilizing the gene carrier, the gene delivery complex or the pharmaceutical formulation. The VBPEA of the invention has a significantly high gene delivery rate compared to existing gene carriers and a complex of the VBPEA with DNA has little or no cytotoxicity and shows a very high in vivo transfection efficiency. In addition, a complex of the VBPEA with siRNA shows high gene silencing efficiency and can induce a high rate of cell death and the inhibition of cell proliferation in cancer cells, suggesting that it can be used for anticancer gene therapy. Thus, the gene carrier VBPEA of the invention can be used as an experimental gene carrier and can also be widely used in gene therapy against various diseases depending on the kind of therapeutic gene.

The invention relates to the technical field of biology, and particularly discloses a method of quickly measuring titer of ascovirus. The method includes: resuspending logarithmic phase Sf9 insect cells; placing into an incubator, standing for culture for 30 min until the cells are attached to walls, abandoning a supernatant culture medium, and replacing with a new Sf-900IISFM culture medium; utilizing a blood ball counting plate to measure cell concentration; taking and well mixing Sf9 insect cell suspension with ascovirus diluent, and inoculating to a 96-hole cell culture tray; disposing in the incubator for culture for 24 h, adding trypan blue dyeing liquid into each hole, and recording dyed cell number and total cell number of each hole; calculating Sf9 insect cell death rate of each hole, determining that the corresponding hole is infected with ascovirus if cell death rate of each hole is lower than that of a control group, determining that the corresponding hole is not infected with ascovirus if not, and calculating TCID50 of ascovirus according to a formula. The method combines cell dyeing, can be used for quick measuring of titer of ascovirus and is more accurate in measuring result.

The invention provides an evaluation method of in-vitro natural killer cell immunocompetence and application thereof. The evaluation method comprises the following steps: carrying out mixed co-cultureon target cells carrying a fluorescence label A and natural killer cells, then adding a fluorescence label B to label the target cells and the natural killer cells, and adding a fluorescence label Cto carry out dyeing labeling on dead cells generated after co-culture; and then carrying out microscopic imaging on the cells by using different fluorescence channels, identifying and analyzing the cells in the same area in the microscopic image by combining an image synthesis analysis method, and evaluating the immunocompetence of the natural killer cells according to an analysis result. According to the evaluation method, multiple data such as the cell death rate, the cell self-injury rate and the cell specific killing rate can be directly obtained through the images, the immunocompetence ofthe natural killer cells is obtained according to the data, and interference of impurities and cell debris is effectively eliminated.

The invention concerns a culture medium containing a polyvinylpyrrolidone as substitute for the serum of animal origin for producing animal or human adherent cells under stirring by increasing the cell proliferation or by decreasing cell death rate. Said medium is also suitable for producing viruses.

The invention discloses a method for establishing a hydrogen peroxide induced oxidation stress model of a mouse monocyte macrophage system. The mouse monocyte macrophage system is treated by adopting hydrogen peroxide in vitro induction, and the concentration of hydrogen peroxide is 25 to 450 microns. Compared with the prior art, the mouse monocyte macrophage system is firstly used as treatment cells of the hydrogen peroxide induced oxidation stress model, the optimal using concentration and cell incubating time of an H2O2 solution are determined by inspecting a cell mortality rate and an intracellular ROS level, the method is easy to operate and relatively low in cost, and researchers for cultivation of mouse monocyte macrophage and an oxidation stress model firstly can be helped to complete the cultivation of the mouse monocyte macrophage and the establishment of the oxidation stress model relatively successfully.

The invention discloses human adipose preserving fluid and a preparing method thereof. Each 1000 ml of human adipose preserving fluid contains 50-70 g of low molecular dextran-40, 50-60 mmol of NaCl,20-30 mmol of KCl, 4-8 mmol of MgSO4, 40-60 mmol of cane sugar, 0.1-0.2 g of penicillin G sodium salt, 0.1-0.2 g of amphotericin, 0.07-0.13 g of gentamicin, 3-5 mmol of reduced glutathione, 4-8 mmol of adenosine and the balance deionized water. The preserving fluid has the pH value of 7.33-7.53. All the components are mixed and dissolved in the deionized water, subpackaged and sealed, and then preserved at 0-4 DEG C. The preserving fluid has a remarkable effect of reducing the adipose cell death rate and keeping the activity of mesenchymal stem cells in fat when used for preserving adipose tissue. In addition, bacteria can be effectively restrained, and the further clinical and scientific research application can be easily conducted on the fat.

The invention relates to a method for judging salinity-tolerance potential of poplar with leaf epidermal cell death rate; the leaf epidermal cell of the poplar carries out plasmolysis under a high-salinity environment, the cells with different salinity-tolerance capacity have different plasmolysis degree, and the cells with high-degree plasmolysis can not be restored and die; natural red of dye stuff is used as indicator, the leaf epidermal cells of the poplar are dyed, different coloring of living cells and dead cells can judge the genetype of the poplars with different salinity-tolerance capacity; the leaf epidermal cell is treated in high-salinity solution for a certain time, the death rate of the leaf epidermal cells can rapidly and accurately reflect the salinity-tolerance capacity of the genetype; by utilizing the judging technique of the death rate of the leaf epidermal cell, the salinity-tolerance potential of the genetype can be accurately judged only for 20-30min, the labors and time are saved, the working efficiency is high, thereby having very wide application prospect.

The invention discloses an efficient HaCaT cell transfection method. In the process that transfection plasmids enter a HaCaT cell through a liposome method, TX-10 is added in a transfection system of the HaCaT cell. As the TX-10 is added in the transfection process, permeability of a eukaryotic cell membrane is improved, and a liposome-DNA compound is promoted to effectively enter the cell. The method is very effective for HaCaT cells thick in cell membrane and difficult to transfect through a traditional liposome method and improves the transfection efficiency by several times. The method also has the applicability for other cells thick in cell membrane and difficult to transfect; as polyethylene glycol octylphenol ether has toxicity to cells when the use amount of polyethylene glycol octylphenol ether is high and the effect is not obvious when the use amount is low, the use amount of the polyethylene glycol octylphenol ether needs to be considered. For HaCaT cells, the best dosage of the TX-10 is 0.005%; under the best dosage, the death rate of HaCaT cells is lowest and the transfection efficiency is highest.

The invention discloses a high-low-temperature continuous stress microalgae culture method. According to the culture method, two-stage culture is carried out, wherein in a pre-culture stage, microalgae cells are cultured to a concentration range of 1.0*10<6>/L-1.2*10<6>/L under an optimal condition of 25 DEG C and 100 [mu]mol/(m<2>.s), and then a microalgae pre-culture solution is used for continuous high-low-temperature stress. The high-low-temperature continuous stress microalgae culture method can greatly shorten the culture period, reduce the cell death rate, and obviously improve the yield of damage repair active substances such as superoxide dismutase, catalase, polyunsaturated fatty acids (PUFAs) and the like.

The invention provides an asymmetric bipolar cell fusion instrument based on HB-MMC and a control method; the asymmetric bipolar cell fusion instrument comprises a shell; a pulse generation module, a sine generation module, a switching circuit and a controller module are arranged in the shell; the controller module is connected with the pulse generation module; the sine generation module is connected with the controller module; the pulse generation module is connected with the switching circuit; the sine generation module is connected with the switching circuit; the switching circuit is connected with the controller module; and the switching circuit sends a pulse voltage signal or/and a sine voltage signal to a load according to a control signal sent by the controller module. Asymmetric adjustment of positive and negative polarity pulse amplitudes, pulse widths and numbers can be realized, so that the second asymmetric pulse can better reduce the action effect of the first pulse, the cell death rate is reduced, the fusion efficiency is improved, and great significance is achieved for the development of biomedical treatment and biopharmacy.

The invention discloses an application of dixanthogenate to inhibit virus to induce MDCK cell death and detecting method of MDCK cell death, which is characterized by the following: the MDCK cell culture liquid is digestive liquid of 0. 22% tryptone and 0. 03% EDTA; the MDCK cell can be target cell to test the influence of dixanthogenate for cell death through amphophilic method on the stream-oriented cell device; the cell death rate has obvious difference (P<0. 01), which proves the cell death induced by influenza virus inhibited by dixanthogenate; the new target is found firstly in the anti-influenza virus of dixanthogenate.

The invention discloses a nozzle apparatus with a package function, and the nozzle apparatus not only is capable of overcoming the problem that the existing 3D biological printing technology is excessively high in cell death rate, but also can realize the uniform arrangement of biological particles. The nozzle apparatus with the package function mainly comprises a nozzle main body, a conical positioning part, a capillary pipe, a pinhead, a locking nut, a quick connector and a sealing screw. The nozzle apparatus with the package function has the characteristics that the conical positioning part is fixedly connected with the nozzle main body by virtue of threads and positioned by virtue of conicity; the capillary pipe is in clearance fit with the conical positioning part to be positioned, and the capillary pipe is fixed in an adhesion manner; the pinhead is fixed to the nozzle main body by virtue of the locking nut and positioned by virtue of the conicity at the outlet end of the nozzle main body, so that the coaxiality requirement of the capillary pipe and the pinhead is met; and two cavities are formed between the conical positioning part and the nozzle main body, an inner cavity and an outer cavity are respectively fully filled with different materials, the pressures of the inner cavity and the outer cavity are respectively controlled by virtue of a pressure feedback and control circuit, the flow rate of the biological material in the inner cavity and the outer cavity is further controlled, the package of cells or active biological materials as well as the uniform arrangement of particles are realized, and the nozzle also has the advantage of easiness in machining.

The invention relates to the technical field of transportation, in particular to cell transportation equipment. The equipment comprises a box body and a containing box, wherein the containing box is used for containing transported cells and arranged in the box body in a suspended mode. The equipment further comprises a fixing piece, wherein the fixing piece is located between the containing box and the inner wall of the box body and is fixedly arranged in the box body, and the fixing piece is provided with a through groove with a notch facing the containing box; the first damping piece is inserted into the through groove and fixedly connected with the groove top and the groove bottom of the through groove, wherein a mounting groove with a notch facing the containing box is formed in the middle of the first damping piece, and the first damping piece is used for damping the containing box; and one end of a second damping piece is detachably inserted into the mounting groove, and the other end of the second damping piece is fixedly connected with the containing box and used for damping the containing box. According to the cell transportation equipment, the problem that the death rateof the transported cells is increased due to poor shockproof performance in the transportation process of an existing cell transportation equipment can be solved.

The present invention relates to single cell array micro-chips and fabrication, electrical measurement and electroporation method thereof. The single cell array microchip comprises a substrate (1), a plurality of positioning electrodes (2) formed in an array, a plurality of measuring electrode-pairs (3) formed in an array, and a micro sample pool (4). The invention integrates cell array positioning with electrical measurement and electroporation for living cells, which is characteristic of label-free and noninvasive methods to manipulate, position particles/cells as well as further measure their electrical parameters. Therefore, single-cell-array positioning and multi-mode in-situ real-time measurement can be realized for intensive analysis. Since the positioned cells are immobile, the precision of the electrical measurement of cells is effectively improved, so is the efficiency of electroporation with lower cell mortality rate.

The invention discloses a method for improving electroporation cell transfection efficiency. The method comprises the following steps: performing electroporation on cell sample liquid to be treated byadopting an electroporation device, wherein at least one of electrodes of the electroporation device is a porous electrode; and, performing electroporation on the cell sample liquid to be treated byapplying a bipolar pulse voltage to the electroporation electrode, wherein the pulse voltage of the bipolar pulse voltage is -2kV to +2kV. According to the invention, the porous electrode is used as the electroporation electrode, the electric double-layer capacitance of the electrode can be increased, the surface partial pressure of the electrode is reduced, the voltage applied to a solution is increased, the solution electrolysis and the cathode effect are relieved, and the cathode effect is a main factor for increasing the death rate of cells and reducing the transfection rate; and meanwhile, due to the fact that partial voltage on the electrodes is reduced, the intensity of applied voltage can be reduced under the same electric field intensity requirement.

The invention discloses a new application of schizandrin A in preparation of a product for antagonizing formaldehyde cytotoxicity. Schizandrin A can antagonize cell death and apoptosis induced by formaldehyde so as to improve the cell survival rate. The invention discloses an application of schizandrin A in preparation of a product for inhibiting the cell death rate from increasing induced by formaldehyde. Schizandrin A plays an important role in antagonizing formaldehyde cytotoxicity, and is significant for preventing diseases caused by formaldehyde.