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11.
Activities of plasma membrane proteinases such as angiotensin-converting enzyme (ACE), aminopeptidases, and dipeptidyl peptidase IV (DPP-IV) were determined in lymphoid cells of various immunological phenotype which were obtained from 30 patients with lymphoproliferative diseases. The enzyme activities significantly varied depending on the immunological phenotype and stage of cell differentiation, but no correlation was found between activities of ACE, DPP-IV, and aminopeptidases in the cells of different type. The cell lysates studied contained at least two classes of aminopeptidases: metal- and sulfhydryl-dependent enzymes. A sulfhydryl-dependent aminopeptidase with activity optimum at pH 8. 5-9.0 was found for the first time and is suggested to be from a poorly studied aminopeptidase family. In addition to ACE, lysates of leukemic T- and B-cells were found to contain an inhibitor of ACE which was not previously described for these cells.  相似文献   
12.
Molecular Biology Reports - The aim of this study was to elucidate the features of the expression of matrix metalloproteinases inducer—EMMPRIN (EMN) and matrix metalloproteinase 1 (MMP-1) in...  相似文献   
13.
Following the immunization of BALB/c mice with B. pertussis toxin, monoclonal antibodies (McAb) to the antigens of human epithelium, both dermal (the basal, superbasal or all epidermis levels) and thymic (the epithelium of the medullary zone, the cortical and medullary epithelium around Hassall's corpuscles), have been obtained. McAb have been obtained as the result of the polyclonal activation of autoreactive B-cells with B. pertussis toxin. McAb thus obtained can be used for the determination of the corresponding antigens in the epithelial tissues of the thymus and other organs in man, as well as for the diagnosis of tumors, histogenetically related to integumentary tissues of the epidermal genesis.  相似文献   
14.
Applied Biochemistry and Microbiology - The production of diadinoxanthin and its cytostatic activity in an intensive culture of C. closterium has been estimated via molecular modeling and...  相似文献   
15.
Hybridomas synthetizing monoclonal antibodies (McAb) to B. pertussis toxin (BPT) and endotoxin, or lipopolysaccharide (LPS), were obtained. The specificity of McAb to BPT was confirmed in the leukocytosis-stimulating factor neutralization test. Two hybridomas synthetized McAb, seemingly active against the common determinant of BPT and LPS. The McAb of one hybridoma reacted with the crude extract of BPT.  相似文献   
16.
B. pertussis suspension was tested by De Voe et al. method (1970) and its modification with the solutions of a definite ionic composition and a lysozyme. The best results were obtained by the following modification elaborated by the authors. The microbes were grown on the casein-carbon agar for 36 hours and were washed with chilled 0.5 M NaCl. The suspension was washed 4 times with the same solution and then the precipitate was suspended in saccharose solution (0.5 M). In 2 hours the saccharose was replaced by a solution of salts with lysozyme. After a 2-hour incubation at 35 degrees C the substance was centrifugated for 20 minutes and the precipitate suspended in the tris-buffer at pH 7.8. The following changes were observed: after the washing and incubation with saccharose there was seen a strong stretching and separation of the cell wall (CW) from the cytoplasmic membrane (CPM); cells without the CW were rarely revealed; 2) after the lysozyme treatment there were many cells of spherical shape (phasic-contrast microscopy) without any CW, limited by the CPM only. Morphologically they were no different from the true protoplasts of the Gram-positive bacteria. The chemical analysis also confirmed a possibility of obtaining the true protoplasts of the Gram-negative bacteria.  相似文献   
17.
Own results of long-term studies of expression of matrix metalloproteinases (MMPs) and their endogenous regulators examined in fibroblasts transformed by oncogene E7 HPV16 (TF), immortalized fibroblasts (IF), cell lines associated with HPV16 and HPV18, and tumor tissue samples from patients with squamous cervical carcinoma (SCC) associated with HPV16 have been summarized. Transfection of fibroblasts with the E7 HPV16 oncogen was accompanied by induction of collagenase (MMP-1, MMP-14) and gelatinase (MMP-9) gene expression and the increase in catalytic activity of these MMP, while gelatinase MMP-2 expression remained unchanged. MMP expression correlated with the tumorigenic of transformed clones. Expression of MMP-9 was found only in TF. In TF expression mRNA TIMP-1 decreased, while expression of the genatinase inhibitor, TIMP-2, increased. Collagenase activity and expression of the MMP-14 (collagenase) mRNA increased, while gelatinase activity remained unchanged. The destructive potential of TF is associated with induction of collagenases, gelatinase MMP-9 and decreased levels of MMP inhibitors. MMP-9 may serve as a TF marker. Invasive potential of cell lines associated with HPV18 (HeLa and S4-1) was more pronounced than that of cell lines associated with HPV16 (SiHa and Caski). In most cell lines mRNA levels of collagenases MMP-1 and MMP-14 and the activator (uPA) increased, while gelatinase MMP-2 mRNA and tissue inhibitors mRNAs changed insignificantly. MMP-2 activity significantly increased in Caski and HeLa cell lines, while MMP-9 expression in these cell lines was not detected. The comparative study of expression MMP of and their endogenous regulators performed using SCC tumor samples associated with HPV16 has shown that the invasive and metastatic potentials of tumor tissue in SCC is obviously associated with increased expression of collagenases MMP-1, MMP-14 and gelatinase MMP-9, as well as decreased expression of inhibitors (TIMP-1 and TIMP-2), and to a lesser extent with increased expression of MMP-2. MMP-1 and MMP-9 can serve as markers of invasive and metastatic potential of the SCC tumor. The morphologically normal tissue adjacent to the tumor tissue is characterized by significant expression of MMP-1, MMP-2, and MMP-9. This also contributes to the increased destructive potential of the tumor.  相似文献   
18.
Contrary to the pre-existing concepts based on morphological and karyological data on the impossibility of hybridization between hamster species of the genus Allocricetulus (A. curtatus and A. eversmanni), F1 hybrids in both combinations, and backcrosses, were obtained for the first time. Some restrictions of hybridization between females of A. eversmanni and males of A. curtatus were detected. Analysis of the synaptonemal complex in the hybrids produced by crossing a female of A. curtatus with a male of A. eversmanni demonstarted that a significant portion of the cells was subject to arrest and selection at the stage of meiosis prophase I. Nevertheless, some spermatocytes still generate viable spermatozoa. Thus, the possibility of hybridization in the laboratory between two Allocricetulus species with different numbers of chromosomes may testify to a relatively low divergence between them.  相似文献   
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20.
Rabbit antisera were prepared against three highly purified enzymes from bovine spleen: proteinase I (cathepsin L), proteinase II (cathepsin H), and cathepsin B. The Ouchterlony double diffusion test shows that each antiserum specifically reacts with the corresponding antigen and does not cross react with other proteinases. These data provide evidence that the three proteinases are distinct with respect to their antigenic properties. Using specific antisera, the identity of two preparations of proteinase I isolated by different methods was demonstrated. Analysis of the fractions obtained in the course of isolation procedure revealed a component reacting with antisera against proteinase I. It had a greater molecular mass than proteinase I (30 000-40 000), was richer in antigenic respect and had a lower proteolytic activity as compared with proteinase I. The effect of various inhibitors and denaturation conditions on antigenic properties of proteinases was also studied.  相似文献   
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