231 results about "Cell membrane permeability" patented technology

A method of determining information about cell viability and other characteristics relating to cell membrane permeability is disclosed. The method involves determining the effect of a cell on current flow and relating that effect to a known standard which standard may be a known healthy cell and thereby deducing the viability of the cell being tested. The cells being tested can be subjected to different environmental conditions such as surrounding chemicals, temperature, pH and pressure to determine the effects of such conditions on cell viability and/or cell permeability. The cell being tested can be in a cell suspension, grown on s ubstarte, in tissue in vitro or in tissue in vivo. The method provides substantially instantaneous results and need not include the use of dyes or other markers.

A cell-penetrating peptide of (A) to (D) below gives cell membrane permeability and transmucosal absorbability to a physiologically active substance:

• • (A) a peptide having the amino acid sequence of SEQ ID NO:1;
  • (B) a peptide represented by SEQ ID NO:1 except that one or several basic amino acids are changed;
  • (C) a peptide represented by SEQ ID NO:1 except that 1 to 5 amino acids are changed;
  • (D) a peptide having: the reverse sequence of any of (A) to (C); an amino acid sequence which is the same as the reverse sequence of (A) except that one or several basic amino acids are changed; or an amino acid sequence which is the same as the reverse sequence of (A) except that 1 to 5 amino acids are changed.

The invention discloses a production process for red tea. The production process comprises the following steps of: (1) fresh leaf withering; (2) freezing; (3) thawing; (4) rolling; (5) fermenting; (6) drying. According to the production process for the red tea, the withering process normally only needs 1-2 hours, and the rolling process needs 15-30 minutes; by carrying out the thawing process, the cell membrane permeability can be increased, the enzymatic oxidation of polyphenol materials can be accelerated, and the withering time and the rolling time are greatly shortened by at least 6 hours than a traditional method, so that the production efficiency is improved; the red tea produced by utilizing the production process has the advantages that the flavor is mellow and tasty, the liquor color and leaves are red and bright, and the quality is high.

The invention relates to a natural preservative antistaling agent, which comprises epsilon-polylysine and alcohol extractions of anise, black plum, Cinnamomum cassia, and purple perilla, and can improve the cell membrane permeability of microorganism, thereby causing microorganism restricted substance leak, and can inhibit the growth of Gram-positive bacteria and Gram-negative bacterium, fungus, and saccharomycete in fresh-cut vegetables, and forming a layer of protective film on the surface of fruits and vegetables. The invention can prevent the intrusion of microbe, and reduces spoilage. When utilized in fresh-cut vegetables, the preservative antistaling agent can reduces the rotten rate and avoid the shortcoming that general chemical preservative needs lower PH, the invention is particularly suitable to the fresh-keeping of low acid foods such as vegetables, and can reduce loss in weight which is caused by water evaporation, and can be used for fresh-keeping of fresh-cut vegetables, inhibits oxidation and browning reaction and nutrient loss, prolongs the goods shelf life, and is a preservative antistaling agent which is safe and has no side effect. The invention can prolong the shelf life by 2-3 days.

Certain substances (e.g., large molecules) that ordinarily cannot traverse the cell membrane of cells can be introduced into cells by applying an alternating electric field to the cell for a period of time, wherein the frequency of the alternating electric field is selected so that application of the alternating electric field increases permeability of the cell membrane. Once the permeability of the cell membrane has been increased, the substance is able to cross the cell membrane. This approach is particularly useful in the context of cancer cells (e.g., glioblastoma).

The invention provides a fluorescent probe represented by the formula (I), wherein R1 and R2 are independently selected from H or an aromatic vinyl group, and at least one of R1 and R2 is the aromatic vinyl group; R3 is selected from H, F, Cl, Br, OH, OCH3, N(CH3)2 or C1-C6 alkyl; and R4 is selected from C1-C6 alkyl. Compared with the prior art, because the fluorescent probe provided by the invention has a relatively large electronic conjugated system and plane, the intensity of the intramolecular charge transfer effect can affect the molecular fluorescence emission intensity; when the fluorescent probe and the G-quadruplex generate a specific action, the flexibility of intramolecular rotatable double bonds is restricted, the intramolecular charge transfer effect is enhanced, and the fluorescence is also enhanced significantly; moreover, the fluorescent probe provided by the invention has the advantages of low biotoxicity, phototoxicity and photobleaching property, good light stability, good water solubility and good cell membrane permeability.

Certain substances (e.g., large molecules) that ordinarily cannot traverse the cell membrane of cells can be introduced into cells by applying an alternating electric field to the cell for a period of time, wherein the frequency of the alternating electric field is selected so that application of the alternating electric field increases permeability of the cell membrane. Once the permeability of the cell membrane has been increased, the substance is able to cross the cell membrane. This approach is particularly useful in the context of cancer cells (e.g., glioblastoma).

Pesticidal concentrate and spray compositions are described which exhibit enhanced efficacy due to the addition thereto of a compound which increases cell membrane permeability, suppresses oxidative burst, or increases expression of hydroxyproline-rich glycoproteins.

The invention discloses a fluorochrome taking fluorescein as matrix, as well as a preparation method and application thereof. The fluorochrome taking the fluorescein as the matrix has the structure shown in a general formula I (figure 1); and the compound has a certain level of water-solubility, and has certain good membrane permeability. The compound disclosed by the invention has novel spectral characteristics; and dye of fluorescein derivative with good property is applied to the fluorescence imaging aspect.

The invention discloses a cavitation-bubble-mediated laser transfection method. According to the method, laser is used to irradiate nano particles with especially strong light absorptivity, the nano particles are combined with a specific cell through a specific ligand and a specific receptor, and cavitation bubbles are generated at the peripheries of the nano particles which are irradiated by the laser. The generation of the cavitation bubbles causes a cell membrane to be temporarily permeable, and thus the transfection of an allogenic material is achieved. The laser is contactless and free from pollution and cytotoxicity, so that the safe gene transfection method is realized; and moreover, as the cell membrane is caused to be permeable through generating the cavitation bubbles, the method is a physical method, can realize the transfection of any type of cells, can realize transfection in large area, and does not need special, expensive and precision instruments.

The invention relates to a method of effectively producing 1, 3-propylene glycol by changing the membrane permeability, which adds nonionics to change the membrane permeability, effectively promotes the cell growth, and increases the concentration of 1, 3-propylene glycol which is the finished product of fermentation. The utility model has the technical process that as follows: adding the second-class germ culture into the fermentation culture; adding nonionics which can improve the membrane permeability to the fermentation culture; the nonionics reduce the resistance of the oxygen and nutrient substance from entering the cell, promote the cell growth, enhance the secreting of metabolite to the extra-cellular area, reduce the accumulation of metabolite in cell, and facilitate the elimination of inhibition of product and sub product, in particular the inhibition of cell growth and cell catalytic activity by 1, 3-propylene glycol. The concentration of the fermentation product--1, 3-propylene glycol is increased by 10 to 70 percent. With simple technical process and low production cost, the invention is easy to be industrially applied.

The invention provides a liposome for delivery to the posterior segment of the eye, comprising (A) a phospholipid, (B) a charged substance, and/or (C) a membrane-reinforcing substance; the liposome having a rigidity that provides the liposome with cell membrane permeability, and having a mean particle diameter of 1 μm or less; and a pharmaceutical composition for a disease in the posterior segment of an eye, comprising a drug encapsulated in the liposome. The liposome is delivered to the posterior segment of the eye by instillation, and is non-cytotoxic; and the pharmaceutical composition for a disease in the posterior segment of the eye comprises the liposome.

The invention relates to a near infrared fluorescence probe adopting nile blue as a parent, a preparation method thereof and applications thereof. The fluorescence probe has a structure shown as the general formula I as the attached drawing 1. The fluorescence probe can effectively improve deficiencies of tumor labeling fluorescence probes at present, can sensitively and accurately response to target cells COX-2 expression amount of which is abnormal, and is suitable for effective specific near infrared fluorescence probes labeling living tumor cells. The fluorescence probe provided by the invention is simple in synthesis and products are easy to obtain. The fluorescence probe provided by the invention has a very low fluorescence background in non-tumor cells and high fluorescence signals in tumor cells, and has strong specific labeling function for tumor cells. In addition, compounds of the type have good cell membrane permeability, low biotoxicity, low phototoxicity and low photobleaching capability and can locate a special organelle of a certain kind tumor cell.

The invention provides a pH sensitive near-infrared fluorescent molecular probe MP-Cy with a structural formula shown as follows. The invention also provides a preparation method of the molecular probe and its application in pH detection. The fluorescent molecular probe has the advantages of novel structure and simple preparation process, can effectively avoid interferences of biological autofluorescence and cell endogenous substances, is high in sensitivity, good in optical stability and good in cell membrane permeability, and can accurately monitor the near-in-vivo neutral physiological pH value fluctuations.

The invention discloses a Pu'er tea yeast fermentation technology. The technology comprises the following steps: (1) cleaning, (2) fermentation, (3) tea overturning, (4) stacking, (5) natural drying and (6) refining. According to the invention, Pu'er tea leaves are fermented in a fermentation room with the assistance of yeast, so that the cell membrane permeability of the Pu'er tea is increased, the enzymatic oxidation of polyphenols substances is promoted, the quality of the Pu'er tea is enhanced and the contents of water extracts, tea pigment, amino-acid and the like of the Pu'er tea are increased; as the Pu'er tea is produced through the adoption of the yeast fermentation technology, the fermentation time is distinctly shortened and the production efficiency is improved. The Pu'er tea, produced by adopting the yeast fermentation technology, is bright in color, full in shape, attractive in appearance, rich and strong in scent and rich in nutrition; the Pu'er tea water has a sweet and faint fragrance and is palatable; color, fragrance, taste, shape and nutrition of the original tea leaves are kept.

Provided are a double-stranded oligo RNA structure and a method of preparing the same, and more specifically, a double-stranded oligo RNA structure in which a polymer compound is covalently bound to a double-stranded oligo RNA in order to improve stability in vivo and a cell delivery efficiency of the double-stranded oligo RNA, and a method of preparing the same.

The double-stranded oligo RNA structure having the optimized structure according to the present invention may not inhibit functions of the double-stranded oligo RNA, but effectively improve stability and cell membrane permeability of the double-stranded oligo RNA, such that the double-stranded oligo RNA may be delivered into the cell even at a low concentration dosage thereof to be significantly used as a tool for treatment of cancer, infectious diseases, and the like, as well as a new delivery system of the double-stranded oligo RNA.

The invention discloses a black tea processing technology. The black tea processing technology includes the steps that firstly, after being spread and dried in the sun, picked fresh tea leaves are frozen for 25-30 days under the temperature condition of -20 DEG C to -15 DEG C; secondly, the frozen tea leaves are withered after being unfrozen, and according to withering, the frozen tea leaves are flatly laid on white cloth, subjected to sunlight withering and stirred one time every 10-20 min; thirdly, the withered tea leaves are rinsed, dehydrated, dried in air and twisted; fourthly, the twisted tea leaf raw materials are subjected to film covering fermentation, fermentation temperature is controlled between 35 DEG C and 40 DEG C, and fermentation is performed for 150-190 min; fifthly, the tea leaf raw materials are dried till the water content of the tea leaf raw materials is 5-7%, and then finished black tea products can be made; the cell membrane permeability is increased due to freezing, and therefore enzymatic oxidation of polyphenol substances can be promoted, the content of theaflavin and thearubigins of black tea can be remarkably increased due to freezing, and tea soup is red and bright and tastes sweet and mellow.

The invention provides a pipeline deodorizing and cleaning effervescent tablet and a preparation method thereof. The raw materials for preparing the effervescent tablet include a deodorant, a foamingagent, a lubricant, a surfactant and a filler, wherein the deodorant is mainly used for eliminating odor-causing microorganisms and decomposing odorous substances and is mainly prepared from sodium dichloro isocyanurate, and the sodium dichloro isocyanurate has the advantages of having strong oxidization and chlorination properties, being safe, stable in chemical property, small in irritation, simple, small in dosage and long in lasting effect. Under the condition of the concentration of 20 ppm, a variety of bacteria, algae, fungi, germs and the like can be quickly killed. The deodorizing andcleaning mechanism is that sodium dichloro isocyanurate slowly releases hypochlorous acid when being in contact with water, changes the cell membrane permeability of odorous microorganisms and denatures proteins, enzymes and DNA cannot be synthetized properly, thus odor sources are rapidly eliminated, and its extremely strong oxidization property causes decomposition to produce sulfides and the like.

The invention relates to the technical field of pH fluorescent probes and particularly relates to a lysosome targeted pH fluorescent probe for monitoring cell autophagy as well as preparation and application of the lysosome targeted pH fluorescent probe. The preparation method comprises the following steps of dissolving 2-(2-aminoethyl)-3',6'-bis(diethylamino) spiro [isoindole-1,9'-xanthan]-3-ketone and 2-(2-methoxyethoxy)4-methyl benzene sulfonic acid ethyl ester in N, N-dimethylformamide, and carrying out heating reflux to obtain a crude product; and removing a solvent from the crude product, and separating through a silica gel column to obtain a pure product. Cytotoxicity tests show that the probe has almost no toxic or side effect on cells, a cell co-localization experiment determinesthat the probe can specifically target a cell lysosome, and a laser confocal microimaging experiment shows that the probe has good cell membrane permeability and can perform high-sensitivity detectionon pH change in the lysosome. The probe provided by the invention can monitor the autophagy process of the cells by detecting the change of pH in the lysosome.

The invention discloses a pig breed brucella bax inhibitor-1 (BI-1) gene deletion strain and a construction method and application thereof. The strain is obtained by replacing a pig breed brucella BI-1 gene with a kanamycin resistance gene, and the method includes the main steps that a pig breed brucella S2 vaccine strain genome is taken as a template, PCR amplification is conducted to obtain an upstream homologous arm and a downstream homologous arm of the BI-1 gene, the upstream homologous arm and the downstream homologous arm of the BI-1 gene and a kanamycin resistance gene fragment also obtained through PCR amplification are together cloned into a pUC18 plasmid, and a homologous recombination deletion plasmid pUC18-BI1-KanR is obtained. The plasmid is used for electrotransformation ofa pig breed brucella competent cell, and through PCR identification, an obtained positive transformant is the pig breed brucella BI-1 gene deletion strain. Compared with a wild strain, the deletion strain shows the characteristics of decreasing the growth rate, reducing colonies, increasing cell membrane permeability, enhancing cell polymerization and the like, and it is indicated that the deletion strain has the potential of serving as a brucella attenuated live vaccine.

The invention discloses near-infrared fluorescent dye THX-Np capable of achieving mitochondrial localization and a preparation method and application of the near-infrared fluorescent dye THX-Np. The structural formula of the dye is shown in (I). The dye has a stable pH fluorescence opening effect in an aqueous phase under the conditions of different pH values, and 2,4-dinitrophenyl ether derivatives prepared by using the dye can be applied to detection of hydrogen sulfide. The invention has the following advantages that the fluorescent dye has pH stability, large Stokes shift, good water solubility, good cell membrane permeability and excellent mitochondrial localization performance, and hydroxyl groups and carboxyl groups of the dye can be easily modified so as to produce tracers relatedto organisms, the 2,4-dinitrophenyl ether derivatives prepared through etherification of hydroxyl groups of the dye have excellent selective recognition of hydrogen sulfide, and an excellent selectivefluorescent probe of hydrogen sulfide detection.

The invention relates to a method for extracting whole peptidoglycan from bifidobacterium longum NQ-1501. The method comprises the following steps of removing fat-like substances on a cell membrane through a degreasing process, extracting teichoic acid to improve cell membrane permeability, removing protein-like substances in cells through an enzymolysis solution, carrying out centrifugation cleaning to remove impurities, and carrying out freeze-drying to obtain whole peptidoglycan. The whole peptidoglycan extracted by the method has a complete cell wall structure and has good antitumor effects. The method has the advantages of strong practicality, simple operation, short period, simple and reasonable processes, low cost, high yield, and good adaptability for large-scale production. The invention also relates to whole peptidoglycan prepared by the method and a medicinal preparation prepared from the whole peptidoglycan.

The invention discloses a 4-N substituted anthracene pyridone fluorescent dye and a preparation method and application thereof. The compound has the structural general formula I, wherein in the general formula I, n is an integer from 1-10; and R is selected from hydrogen atom, methyl, hydroxyl, amino group, dimethylamino group, trimethyl ammonium halide group and guanidine hydrochloride group. The 4-N substituted anthracene pyridone fluorescent dye disclosed by the invention is simple to synthesize, and has good light stability, relatively long emission wavelength and good cellular membrane permeability. Therefore, the invention also aims to provide application of the 4-N substituted anthracene pyridone fluorescent dye in biological dyeing, and the 4-N substituted anthracene pyridone fluorescent dye can be used for dyeing fixed cells, living cells and biological tissues.