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1.
Vestn Otorinolaringol ; 89(1): 21-27, 2024.
Article in Russian | MEDLINE | ID: mdl-38506021

ABSTRACT

Chronic sensorineural hearing loss (SNHL) is a common disease that leads to disability of the population. Despite the many reports devoted to SNHL, the question of the pathogenesis of the disease is still open. Many researchers consider the development of SNHL as a manifestation of microangiopathy. The mechanism of development of microangiopathy in SNHL is multifactorial, but most researchers agree that endothelial dysfunction (ED) triggers a complex of pathological changes in the vessels of the inner ear. OBJECTIVE: Review of the results of scientific research in recent years on the problem of etiopathogenesis of sensorineural hearing loss from the perspective of endothelial dysfunction in the formation of auditory disorders.


Subject(s)
Ear, Inner , Hearing Loss, Sensorineural , Humans , Hearing Loss, Sensorineural/etiology , Hearing Loss, Sensorineural/epidemiology
2.
J Chromatogr A ; 1590: 121-129, 2019 Apr 12.
Article in English | MEDLINE | ID: mdl-30679044

ABSTRACT

A novel electrochemical method of preparation of standard gas mixtures for calibration of gas-analytical equipment with O2, H2 and CO was elaborated. Utilization of solid state electrolyte membrane allows to perform a nearly 100%-efficient electrochemical generation or conversion of the analyte and avoid some problems typical for liquid electrolytes, such as solvent evaporation and condensation at the inner walls of the gas tubes or deviations from the Faraday's law. Analysis of uncertainties associated with the calibration procedure showed that the lowest systematic errors are achieved when the calibrant is generated during the electrolysis (i.e. anodic evolution of oxygen or cathodic generation of CO), and the major uncertainties are associated with operation of the flow controllers. For calibration with H2, where the calibrant is partially converted during the electrochemical process, the total uncertainty is essentially determined by molar fractions of the components in H2-Ar mixture, instrumental errors of the equipment, primarily by precision of mass-flow controllers or stability of the gas flow, and the initial flow rate of the calibrant-containing gas mixture. The relative total errors of calibration with oxygen are assessed to be 5-6%; similar uncertainties were calculated for analysis of oxygen content in standard gas mixtures by chromatography using the electrochemical method of calibration.


Subject(s)
Chromatography, Gas/methods , Electrochemical Techniques/methods , Electrolytes/chemistry , Gases , Calibration , Gases/analysis , Gases/chemistry , Membranes, Artificial
3.
Adv Gerontol ; 31(2): 246-249, 2018.
Article in Russian | MEDLINE | ID: mdl-30080332

ABSTRACT

The article compares the flow of intestinal infections in elderly and young people. Analyzed the medical records of 172 persons 60-85 years and 82 history persons 20-40 years with salmonellosis, shigellosis and rotavirus gastroenteritis. It is revealed that bacterial intestinal infections, salmonellosis and shigellosis, those over 60 years of age have the clinical differences and flow is heavier than in patients 20-40 years. Clinic of rotaviral gastroenteritis is not age-appropriate. Knowledge of clinic of intestinal infections in persons of elderly and senile age should your doctor for early diagnosis and proper treatment of patients of this category.


Subject(s)
Gastroenteritis/diagnosis , Adult , Age Distribution , Aged , Aged, 80 and over , Dysentery, Bacillary/diagnosis , Gastroenteritis/microbiology , Gastroenteritis/virology , Humans , Medical Records , Middle Aged , Rotavirus Infections/diagnosis , Salmonella Infections/diagnosis , Young Adult
4.
Mol Hum Reprod ; 16(10): 743-51, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20508064

ABSTRACT

The recently identified trans-membrane G protein-coupled estrogen receptor 1 (GPER, GPR30) has been implicated in rapid non-genomic effects of estrogens. This focuses on expression and localization of GPER mRNA and protein in normal cyclic endometrium and early pregnancy decidua. Real-time PCR, western blotting, in situ hybridization and immuno-histochemistry were used. Endometrial expression of GPER mRNA was lower in the secretory phase than in the proliferative phase, and even lower in the decidua. The expression pattern was similar to that of ERα mRNA, but different from that of ERß mRNA. Western blot detected GPER protein as a 54 kDa band in all endometrial and decidual samples. In contrast to the mRNA, GPER protein did not show cyclic variations. Apparently, a lower amount of mRNA is sufficient to maintain protein levels in the secretory phase. GPER mRNA was predominantly localized in the epithelium of mid- and late-proliferative phase endometrium, whereas expression in early proliferative and secretory glands could not be distinguished from the diffuse stromal signal, which was present throughout the cycle. Immuno-staining for GPER was stronger in glandular and luminal epithelium than in the stroma throughout the cycle. The cyclic variations of GPER mRNA obviously relate to strong epithelial expression in the proliferative phase, and the expression pattern suggests regulation by ovarian steroids. GPER protein is present in endometrial tissue throughout the cycle, and the epithelial localization suggests potential functions during sperm migration at mid-cycle, as well as decidualization and blastocyst implantation in the mid-secretory phase.


Subject(s)
Decidua/metabolism , Endometrium/metabolism , Receptors, G-Protein-Coupled/metabolism , Blotting, Western , Female , Humans , Immunohistochemistry , In Situ Hybridization , Menstrual Cycle/genetics , Menstrual Cycle/metabolism , Polymerase Chain Reaction , Pregnancy , Receptors, Estrogen , Receptors, G-Protein-Coupled/genetics
5.
Mol Hum Reprod ; 12(8): 497-503, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16809379

ABSTRACT

We have previously reported that endometrial mRNA expression of both tissue inhibitors of metalloproteinase-4 (TIMP-4) and matrix metalloproteinase-26 (MMP-26) peaks in the early secretory phase, which implies a role in implantation. The objective of this study was to compare the distribution of TIMP-4 and MMP-26 in endometrial tissue and uterine fluid over the menstrual cycle. Endometrial tissue was analysed with in situ hybridization and immunohistochemistry to localize mRNA and protein for TIMP-4 and MMP-26 in the same set of samples. TIMP-4 mRNA was quantified in separated stromal and epithelial cells using real-time PCR. Uterine fluid was analysed with western blotting. TIMP-4 mRNA was exclusively localized to the stroma, whereas MMP-26 mRNA was expressed by epithelial cells. TIMP-4 protein was only occasionally found in the stroma but was consistently present in granules of the apical part of luminal and glandular epithelial cells. TIMP-4, but not MMP-26, was demonstrated in uterine fluid. Thus, TIMP-4 is produced in the stroma only, secreted by stromal cells, taken up by epithelial cells, accumulated in apical granules and finally secreted to the uterine fluid. Maximal expression of MMP-26, and its strongest inhibitor TIMP-4, in the early and mid-secretory phase suggests a role during implantation. MMP-26 is stored in epithelial cells in its active form, is not released spontaneously and is controlled by TIMP-4 in both stroma and uterine fluid.


Subject(s)
Endometrium/metabolism , Epithelial Cells/metabolism , Matrix Metalloproteinases/metabolism , Stromal Cells/metabolism , Tissue Inhibitor of Metalloproteinases/genetics , Adult , Aged , Blotting, Western/methods , Embryo Implantation , Endometrium/cytology , Female , Gene Expression/genetics , Humans , Immunohistochemistry/methods , In Situ Hybridization/methods , Matrix Metalloproteinases/urine , Matrix Metalloproteinases, Secreted , Pregnancy , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Tissue Inhibitor of Metalloproteinases/metabolism , Tissue Inhibitor of Metalloproteinases/urine , Uterus/metabolism , Tissue Inhibitor of Metalloproteinase-4
6.
Mol Hum Reprod ; 10(9): 655-63, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15243126

ABSTRACT

Normal endometrium is a highly dynamic tissue, which responds to ovarian steroids with cyclic proliferation, differentiation (secretion), and degradation (menstruation). The urokinase plasminogen activator (uPA)-dependent proteolytic cascade as well as ligand activation of the uPA receptor (uPAR) is critically involved in physiological as well as pathophysiological aspects of tissue expansion and remodelling. Cyclic variation and distribution of uPA, uPAR and plasminogen activator inhibitor 1 (PAI-1) mRNA were examined by in situ hybridization, real-time PCR and northern blot in normal endometrium. Their corresponding proteins were localized with immunohistochemistry. uPA mRNA is exclusively expressed by stromal cells, whereas uPA protein is present in both epithelial and stromal cells. Immunostaining for uPA protein is reduced or undetectable at midcycle, thus coinciding with peak concentration of uPA in the uterine fluid. uPAR mRNA is expressed by epithelial cells in the proliferative phase and by stromal cells in the secretory phase. However, epithelial cells stain for uPAR protein throughout the cycle, suggesting that uPAR may detach from stromal cells and then bind to epithelial cells in the secretory phase. PAI-1 mRNA is located in vessel walls. The late secretory phase has greatly increased expression of all three mRNA and their proteins, mainly in pre-decidual cells in the superficial stroma. Discordant localization of the mRNA and proteins suggest that uPA is produced by stromal cells, released and bound to epithelial cells in both the proliferative and secretory phases, whereas uPAR is released from the stroma and bound to epithelial cells in the secretory phase. Also, the present data together with earlier reports suggest that uPA is released from the epithelial cells to the uterine fluid.


Subject(s)
Endometrium/metabolism , Menstrual Cycle/physiology , Plasminogen Activator Inhibitor 1/metabolism , Receptors, Cell Surface/metabolism , Urokinase-Type Plasminogen Activator/metabolism , Endometrium/cytology , Female , Humans , Immunohistochemistry , In Situ Hybridization , Plasminogen Activator Inhibitor 1/genetics , Receptors, Cell Surface/genetics , Receptors, Urokinase Plasminogen Activator , Urokinase-Type Plasminogen Activator/genetics
7.
Neoplasma ; 49(6): 418-25, 2002.
Article in English | MEDLINE | ID: mdl-12584592

ABSTRACT

Although cellular experiments have elucidated a number of active principles in the study of the multidrug resistance (MDR) phenomena, most of the drug resistant tumor cells were derived from different parental cell lines. This fact limits generalization of some experimental data and conclusions, and therefore we selected and characterized cell lines resistant to various anti-cancer agents derived from four parental cell lines: CEM (human T-lymphoblastic leukemia), K562 (human myeloid leukemia), A549 (human lung adenocarcinoma) and MDAMB 231 (human breast adenocarcinoma). In total we obtained a set of 42 resistant sublines, which is an excellent tool for the future studies of different aspects of MDR. In this study we report on some basic characteristics of these sublines, namely, cross-resistance to other anti-cancer drugs investigated by in vitro MTT assay, expression of MDR associated proteins (Pgp, MRP1, LRP, GST-pi and Topo IIalpha) as well as the functional activity of Pgp and MRP.


Subject(s)
ATP-Binding Cassette Transporters/metabolism , Drug Resistance, Multiple , Multidrug Resistance-Associated Proteins/metabolism , Neoplasm Proteins/metabolism , Neoplasms/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Antineoplastic Agents/pharmacology , Drug Resistance, Neoplasm , Female , Genes, MDR , Humans , In Vitro Techniques , Tumor Cells, Cultured
8.
Rozhl Chir ; 81(10): 527-37, 2002 Oct.
Article in Czech | MEDLINE | ID: mdl-12564094

ABSTRACT

The surgeon is frequently faced with the task of bioptic sampling of tissues from patients with tumourous diseases. The importance of such frequently minor procedures is incorrectly underrated. The importance of biopsy is in the foreground in particular at present at a time of individualization of treatment of malignant tumours, based on the development of new diagnostic-therapeutic methods. The bioptic specimen is the fundamental link in the basic decision--benignity or malignity--and also a unique source for assessment of prognostic and predictive factors on the basis of which we select the optimal therapeutic procedure. Contrary to current histopathological examination where the principles of correct collection of tissues specimens are generally known, in recent years the importance of molecular examinations is increasing where the surgeon must respect certain different principles to make the sampling successful. The authors working in a department of surgical oncology along with authors from specialized laboratories formulate rules of correct implementation of biopsies and transport of biological material in conjunction with recent laboratory methods, and based on examples of their own practice, they demonstrate how the initial approach of the surgeon can influence in a decisive way the correct diagnosis and therapeutic procedure in oncological patients.


Subject(s)
Biopsy/methods , Neoplasms/pathology , Biopsy, Needle/methods , Cytodiagnosis , Cytogenetic Analysis , Humans , Neoplasms/diagnosis , Specimen Handling/methods
9.
Prikl Biokhim Mikrobiol ; 36(6): 694-700, 2000.
Article in Russian | MEDLINE | ID: mdl-11116915

ABSTRACT

Five synergistic combinations of biocides were found, among which the combination of kathon + copper sulfate was the most efficient against Serratia marcescens. Depending on the ratio of these biocides, the synergistic effect of this pair allowed 4-20-fold decreases in the effective concentrations. Combinations of biocides with salts (carbonates and phosphates) that facilitate passivation of steel were found, which considerably decreased the corrosion losses of mild steel in comparison to isolated treatment with biocides or salts. The data showed that biocides must be added to corrosion-prone systems simultaneously with the beginning of their exploitation. Otherwise, considerably excessive amounts of biocides or their synergistic compositions are needed.


Subject(s)
Bacteria , Biodegradation, Environmental , Corrosion , Fungi , Fungicides, Industrial
10.
Mol Pathol ; 53(3): 145-9, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10897334

ABSTRACT

BACKGROUND: In vitro the Epstein-Barr virus (EBV) encoded latent membrane protein 1 (LMP-1) has been shown to upregulate expression of matrix metalloproteinase 9 (MMP-9), a member of a family of zinc dependent endopeptidases that is believed to facilitate tumour invasion and metastasis by degradation of the extracellular matrix. AIM: To test whether the expression of MMP-9 in Hodgkin's disease correlates with EBV status and survival and to investigate whether LMP-1 expression affects MMP-9 concentrations in the Hodgkin's disease cell line, L428. METHODS: MMP-9 expression was measured by means of immunohistochemistry in a series of Hodgkin's disease tumours and this expression was correlated with EBV status and survival. The influence of LMP-1 on MMP-9 expression was also investigated in the Hodgkin's disease cell line, L428. RESULTS: MMP-9 expression was demonstrated in the malignant Hodgkin and Reed-Sternberg cells of all (n = 86) formalin fixed, paraffin wax embedded Hodgkin's disease tumours examined. Although the intensity of MMP-9 immunostaining varied between cases, there was no correlation between MMP-9 expression and EBV status or survival. MMP-9 expression was also detected in a variety of non-malignant cells, including fibroblasts. MMP-9 was detected by zymography in the L428 and KMH2 Hodgkin's disease cell lines, whereas low or undetectable amounts of MMP-9 were found in the L591 Hodgkin's disease cell line. Induction of LMP-1 expression in the Hodgkin's disease cell line L428 did not result in a detectable increase in the values of MMP-9 as measured by zymography. CONCLUSIONS: These results demonstrate that MMP-9 is consistently expressed by the Hodgkin and Reed-Sternberg cells of Hodgkin's disease tumours and by the Hodgkin's disease cell lines, L428 and KMH2. However, this expression does not appear to be related either to LMP-1 values or to survival.


Subject(s)
Biomarkers, Tumor/metabolism , Herpesvirus 4, Human/isolation & purification , Hodgkin Disease/enzymology , Matrix Metalloproteinase 9/metabolism , Blotting, Western , Hodgkin Disease/virology , Humans , Immunoenzyme Techniques , Survival Rate , Tumor Cells, Cultured , Viral Matrix Proteins/metabolism
11.
Rozhl Chir ; 79(3): 134-8, 2000 Mar.
Article in Czech | MEDLINE | ID: mdl-10838948

ABSTRACT

The authors present an account on the initiation of a study concerned with the administration of cytostatics according to the sensitivity of the tumour cells. To assess the sensitivity the MTT test was used. The method is described in the paper. Four groups of tumours were examined by the MTT test: breast cancer, carcinoma of the colon and rectum, of the lungs and oesophagus + stomach. Six cytostatics were tested: 5-fluorouracil, cisplatinum, daunorubucin, paclitaxel, vincristine, and vepeside. Evaluation of the sensitivity of different tumours was based on the median of TCS50. The results of the MTT test were not used so far in the therapeutic protocol in all patients where the examination was made, as in solid tumours, contrary to haemo-blastomas, usually common empirically tested protocols are used. The authors reflect whether individually administered cytostatics according to the MTT test can improve the prognosis of patients with malignant diseases. They assume that long-term follow-up of the patients may provide favourable results in particular because more and more effective cytostatics are becoming available.


Subject(s)
Antineoplastic Agents/pharmacology , Drug Screening Assays, Antitumor , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Survival/drug effects , Female , Gastrointestinal Neoplasms/drug therapy , Gastrointestinal Neoplasms/pathology , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology
12.
Adv Exp Med Biol ; 457: 461-71, 1999.
Article in English | MEDLINE | ID: mdl-10500823

ABSTRACT

This study was designed to compare the antileukemic activity of prednisolone and dexamethasone in childhood acute lymphoblastic leukemia (ALL) under in vitro conditions. The chemoresistance of leukemic cells was ascertained by means of a MTT assay in 69 ALL children at diagnosis and the concentration killing 50% of leukemic cells (LCS50) was determined. The children were treated using the protocol ALL-BFM 90/95. Statistical correlations were made among prednisolone (PRED) and/or dexamethasone (DEX) LCS50 and absolute number of blast cells (ANB) on day 0/8 and a new parameter named blast cells clearance (BCC, BCC8 [%] = ANB8: ANB0 x 100) on day 8. Despite the previously published results of Ito et al. (J. Clin. Oncol. 14: 2370-2376, 1996) and Kaspers et al. (MPO 27: 114-121, 1996) on a positive correlation of DEX versus PRED LCS50 (p < 0.002), in our study, we identified 30% of children (21/69) with differential in vitro responsiveness to PRED and DEX. 16% of patients (11/69) were highly sensitive to DEX and resistant to PRED, while 14% of them (10/69) were resistant to DEX and highly sensitive to PRED. The major difference found in our and the other studies was in the processing of leukemic cells. These results were confirmed in a model experiment using the CCRF-CEM line, where we showed that sensitivity to PRED and DEX, but not to other anti-cancer drugs critically depends on manipulation with tumor cells (cryopreservation). Correlation of PRED/DEX in vitro sensitivity values with parameters of in vivo patient's response to PRED monotherapy identified significant association of PRED LCS50 with BCC8 (p < 0.02). It indicates strong linkage of in vitro sensitivity to PRED with percentage of blast cells eliminated from patient blood within the first 8 days of PRED monotherapy.


Subject(s)
Antineoplastic Agents/toxicity , Dexamethasone/toxicity , Drug Resistance, Neoplasm , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Prednisolone/toxicity , Adolescent , Blast Crisis , Bone Marrow/pathology , Cell Line , Child , Drug Screening Assays, Antitumor , Female , Humans , Male , Precursor Cell Lymphoblastic Leukemia-Lymphoma/blood , Tumor Cells, Cultured
13.
Vestn Ross Akad Med Nauk ; (6): 20-4, 1997.
Article in Russian | MEDLINE | ID: mdl-9289273

ABSTRACT

Limited proteolysis has established that the protective antigen (PA) molecule consists of four functional-active domains. So, the shielding domain borrows an area in the linear structure of the PA molecule with NH2 of the end up to Lys 166 and plays a conducting role in the proteolytic activation of PA. The associative domain, engaging in the area Arg 167-Met266, plays a key role in the interaction with LF or EF at self-assembly toxic complexes LT or ET. The stabilizing domain borrows in the linear structure of the PA molecule are with Gly351 up to Met434. On the one hand, this area promotes formation with LF conformationally steady toxic complex's, and, on the other, takes a direct participation in the formation of a hydrophobic channel by which the molecule LF or EF enters the target cell. The receptor domain, representing a COOH-terminal area, starting from Leu663 amino acid, begins to interact with specific receptors on the macrophages and thus delivers the toxic complex to the target cell. It has been found that in the molecule of lethal factor there are 3 functionally active domains located in the linear structure of the molecule as follows: the associative domain borrows an area from Lys39 up to Met242, stabilizing and effector domains occupy areas from Leu517 to Lys614 and from that point to Lys COOH-terminal amino acid.


Subject(s)
Antigens, Bacterial/immunology , Bacillus anthracis/immunology , Bacterial Toxins/immunology , Epitopes/immunology , Macrophages, Peritoneal/immunology , Animals , Anthrax/immunology , Anthrax/prevention & control , Mice , Mice, Inbred CBA , Molecular Structure , Structure-Activity Relationship
14.
Anticancer Drugs ; 8(10): 1007-13, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9436644

ABSTRACT

This case report describes a dog with spontaneous melanoma of the orofacial region which was treated by a synthetic inhibitor of cyclin-dependent kinases, i.e. olomoucine (OC). The drug was applied i.v. in a single dose of 8 mg/kg/day for 7 days in succession. Repeated bioptic examinations of metastatic cervical lymph nodes showed rapid induction of apoptosis in tumor cells as early as on the third day of treatment. Standard clinical and laboratory examinations did not reveal side effects of the therapy. There were no detectable manifestations of myelosuppression, hepatotoxicity, nephrotoxicity or neurotoxicity. However, transient anemia developed following bleeding from a devitalized tumor mass. For this reason, the dog underwent surgery to minimize tumor load as well as to eliminate the source of bleeding. Two kilograms of primary tumor were extirpated in the course of surgery, including cervical node metastases. Unfortunately, the dog died soon after surgery due to respiratory depression. Histological examinations of the tumor tissue showed marked apoptosis of melanoma cells in both the primary tumor and metastases. The induction of programmed cell death of cancer cells by OC resulted in rapid eradication of at least 68% of the tumor cells. The remaining melanoma cells retained at least equally well in vitro sensitivity to OC as to drugs currently used in clinical practice.


Subject(s)
Antineoplastic Agents/therapeutic use , Apoptosis/drug effects , Cyclin-Dependent Kinases/antagonists & inhibitors , Dog Diseases/drug therapy , Enzyme Inhibitors/therapeutic use , Facial Neoplasms/veterinary , Melanoma/veterinary , Purines/therapeutic use , Animals , Dog Diseases/enzymology , Dog Diseases/pathology , Dogs , Kinetin , Male
15.
Mol Gen Mikrobiol Virusol ; (3): 20-2, 1996.
Article in Russian | MEDLINE | ID: mdl-8999313

ABSTRACT

Three functional domains were revealed in the molecule of the lethal factor of B. anthracis. They are located in the linear structure of the molecula as follows: the associative domain occupies the area from Lys39 to Met242, the stabilizing domain from Leu517 to Lys614, and the effector domain still further to the COOH-terminal Lys mino acid.


Subject(s)
Antigens, Bacterial , Bacillus anthracis/chemistry , Bacterial Toxins/isolation & purification , Exotoxins/isolation & purification , Amino Acid Sequence , Animals , Bacterial Toxins/metabolism , Binding, Competitive , Exotoxins/metabolism , Mice , Mice, Inbred CBA , Molecular Sequence Data
16.
Mol Gen Mikrobiol Virusol ; (3): 16-20, 1996.
Article in Russian | MEDLINE | ID: mdl-8999312

ABSTRACT

Using the limited proteolysis method, we established that the protective antigen (PA) molecule consists of four functionally active domains. The shielding domain occupies an area in the linear structure of the molecule PA with NH4-terminal up to Lys166 and plays an important role in the proteolytic activation of PA. The associative domain situated in the Arg167-Met266 region is responsible for interactions with either lethal or edematous factors in self-assembly of the toxic complexes of the lethal or edematous toxin. The stabilizing domain occupies the Gly351 to Met434 area. On the one hand, this area promotes the formation of conformationally stable toxic complexes with the lethal factor, on the other, directly participates in the formation of the hydrophobic canal, through which the molecule of the lethal or edematous factor and, evidently, a fragment of PA molecule as well (from Arg167 to Gly314), including the associative gene, gets inside the target cell. The receptor domain representing a COOH-terminal region, starting from Leu663 amino acid, interacts with the specific receptors on macrophages and thus delivers the toxic complex to the target cell.


Subject(s)
Antigens, Bacterial , Bacillus anthracis/chemistry , Bacterial Toxins/isolation & purification , Exotoxins/isolation & purification , Amino Acid Sequence , Animals , Bacterial Toxins/metabolism , Bacterial Toxins/toxicity , Binding, Competitive , Chromatography, High Pressure Liquid , Exotoxins/metabolism , Exotoxins/toxicity , Hydrolysis , Macrophages, Peritoneal/metabolism , Mice , Mice, Inbred CBA , Molecular Sequence Data
17.
Article in Russian | MEDLINE | ID: mdl-3898669

ABSTRACT

The conditions of cultivation, ensuring the maximum accumulation of intracellular thermolabile enterotoxin in the cultures of two E. coli strains of different origin, have been studied. Culture media manufactured in the USSR have been selected and the conditions of cultivation, necessary for obtaining intracellular thermolabile enterotoxin in preparative amounts, have been established. Under these conditions the yield of thermolabile enterotoxin in 1.4 mg per 1 liter of culture medium for strain H74-114 and 1.0 mg per 1 liter of culture medium for strain 86.


Subject(s)
Culture Media/metabolism , Enterotoxins/biosynthesis , Escherichia coli/metabolism , Dose-Response Relationship, Drug , Drug Stability , Escherichia coli/drug effects , Hot Temperature , Hydrogen-Ion Concentration , Lincomycin/pharmacology
18.
Int J Biochem ; 16(2): 201-6, 1984.
Article in English | MEDLINE | ID: mdl-6705970

ABSTRACT

Four fragments (F1-F4) of SEA, obtained via papain proteolysis were separated and isolated as individual components by means of the SDS-electrophoresis in polyacrilamide gel. Molecular masses of the pairs F1 + F4 and F2 + F3 are equal to the mass of the intact toxin--a fact that supposes a cleavage of polypeptide chain in two regions of "disulphide loop" in a SEA molecule. Neither fragment possesses any enterpathogenic properties. It was established, that interferonogenic and mitogenic activity of SEA is connected only with the part of molecule corresponding to F1(17,500) and F3(15,000). Two kinds of antigenic determinants in the SEA molecule were found: one was attributed to F1 and F3 fragments, the other was localised in F2 and F4. Proteolysis by trypsin led to cleavage of a small peptide from the N-terminal end of toxin molecule. Trypsinized SEA displayed all kinds of biological activity characterizing the native toxin.


Subject(s)
Enterotoxins/physiology , Animals , Antigens, Bacterial , Cats , Enterotoxins/immunology , Humans , In Vitro Techniques , Interferon Inducers , Papain , Peptide Fragments/immunology , Peptide Fragments/isolation & purification , Peptide Fragments/physiology , Trypsin
19.
Antibiotiki ; 28(3): 214-8, 1983 Mar.
Article in Russian | MEDLINE | ID: mdl-6407389

ABSTRACT

Pretreatment of the cultures of human peripheral blood leukocytes and splenocytes with the incubation medium of the mitogen-stimulated human lymphoid cells containing various concentrations of lymphokines (including 10 to 1280 units/ml of immune interferon) resulted in increased (by at least 4 times) production of interferon, induced by staphylococcal enterotoxin A, phytohemagglutinin and mitogen from Phytolacca americana (PWM), as well as in intensification of DNA synthesis in the producing cells. A more pronounced specific binding of the inductor labeled with radioactive iodine to the producing cells was also observed.


Subject(s)
Interferon Inducers/pharmacology , Interferon-gamma/biosynthesis , Interferon-gamma/pharmacology , Cells, Cultured , DNA/biosynthesis , Fibroblasts/immunology , Humans , Leukocytes/immunology , Lymphokines/pharmacology , Mitogens/pharmacology , Spleen/cytology , Spleen/immunology , Time Factors
20.
Int J Biochem ; 15(3): 285-8, 1983.
Article in English | MEDLINE | ID: mdl-6403393

ABSTRACT

1. The presence of specific binding of [125I]SEA with human splenocytes is established. 2. The association of toxin at 4 C is characterized by saturation, reversibility and a great affinity to a receptor (Kd = 4.0 x 10(-7) M). 3. The number of binding sites on a cell is equal to 6000. 4. At 23 C the binding of labelled toxin with a cell described by a biphasic curve. 5. Priming increases the association of SEA with the splenocytes and correspondingly increases the production level of gamma-interferon.


Subject(s)
Enterotoxins/metabolism , Interferon-gamma/biosynthesis , Protein Binding , Spleen/metabolism , Staphylococcus/metabolism , Humans , Lymphocytes/metabolism
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