A study of the protein composition of the zona pellucida of mammalian oocytes and zygotes by a method of microelectrophoresis in polyacrylamide gel

It is known that drugs are not unlimitedly stable. Dilutions of the antineoplastic agent daunoblastin used in the clinic and experimental work, were examined, whether they could be stored for several days. By means of impulscytophotometry, spectral-photometric measurements, counting of surviving cells and estimation of DNA-synthesis after culturing pieces of tissue in the presence of daunoblastin it could be established that this drug, diluted even four days ago, still possesses sufficient activity.     

Measurement of integrated sensory-motor function following brain damage by a computerized preview tracking task

A preview tracking task has been developed which has particular application to neurological assessment and rehabilitation. Generated and monitored by a graphic display computer, it permits accurate global quantification of the upper-limb sensory-motor system. The incorporation of 'preview' into the tracking task is considered to significantly increase its effectiveness and relevance in relation to normal daily activities. Applied to three groups of normal subjects, several features of normal psychomotor performance and learning were identified or verified: hand dominance is not significant in overall arm control; learning does not completely plateau; increase in age (15-59 years) results in only a minor overall decrement in performance; an initial wide performance distribution decreases dramatically in subsequent sessions. Applied to brain-damaged patients, particularly head injury or stroke, the preview tracking task allows assessment at regular intervals enabling sensory-motor recovery curves to be generated. The potential of this technique, to help determine the efficacy of therapeutic procedures on the recovery process, is illustrated with the presentation of results from three brain-damaged patients demonstrating zero, significant and disjointed recovery of sensory-motor function. The usefulness of the preview tracking task can be expanded by combination with a less frequently applied but more component specific neurological assessment battery.     

The number and biodiversity of the parasites from small mammals in the evacuation area of the Chernobyl Nuclear Power Station

The study of the micromammalian parasite complexes in the Belorussian part of the evacuation zone of the Chernobyl nuclear station revealed 13 species of Coccidia and 30 species of ectoparasitic Arthropoda. Total increase of abundance and biodiversity of both parasites and their hosts was observed. The part of ectoparasites being epidemically hazardous was significantly increased. An analysis of a long-term dynamics of parasite abundance reveals their adaptation to new conditions in the Belorussia.     

Multiple effects of CD4 CDR3-related peptide derivatives showing anti-HIV-1 activity on HIV-1 gp120 functions

The interaction of the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 with CD4 CDR3-related peptide derivatives showing anti-HIV-1 activity has been studied. Conformational changes in gp120, which could affect its interaction with CD4 and its shedding from virions, were detected by fluorescence spectrum analysis of tryptophan residues after addition of peptide representative of the CD4 CDR3-related region, but not the CD4 CDR2-related region. Interestingly, the addition of scrambled peptide, S1 (with altered amino acid sequence compared with the native CDR3-related peptide but unaltered overall composition), which we recently showed to have stronger anti-HIV-1 activity than the original CDR3-related peptide, had no effects on the conformational change in gp120 or on its interaction with CD4 and its shedding from HIV-1 virions. However, all of the CDR3-related peptides, including S1, showed blocking effects on the binding of antibodies against gp120 V3 loop and C-terminus regions. Thus, we concluded that there were at least two separable activities of the CDR3-related peptides in anti-HIV-1 activity, i.e. induction of conformational changes in gp120, which could affect its binding to CD4 and to gp41 (as observed in native CDR3-related peptides), and inactivation of V3 loop and C-terminus regions in gp120 (as observed in all of the CDR3-related peptides, including S1).     

The role of oncostatin M in animal and human connective tissue collagen turnover and its localization within the rheumatoid joint

OBJECTIVE: To study the interaction of interleukin-1alpha (IL-1alpha) and oncostatin M (OSM) in promoting cartilage collagen destruction. METHODS: Bovine, porcine, and human cartilage and human chondrocytes were studied in culture. The levels of collagenase (matrix metalloproteinase 1 [MMP-1]) and tissue inhibitor of metalloproteinases 1 (TIMP-1) were measured by bioassay and enzyme-linked immunosorbent assay (ELISA). The levels of OSM in rheumatoid synovial fluid were measured by ELISA. RESULTS: When combined with OSM, IL-1alpha, IL-1beta, and tumor necrosis factor alpha released proteoglycan and collagen from cartilage. OSM was the only member of the IL-6 family to have this effect. Human tendon also responded to IL-1alpha and OSM. OSM increased the production of MMP-1 and TIMP-1 but when combined with IL-1alpha, synergistically promoted MMP-1 production in human chondrocytes and synovial fibroblasts. High levels of OSM were found in human rheumatoid synovial fluids, and confocal microscopy showed that OSM was produced by macrophages in rheumatoid synovial tissue. CONCLUSION: These results highlight an important new mechanism by which there is irreversible loss of collagen from cartilage.     

Inhibition of acid secretion in gastric parietal cells by the Ca2+/calmodulin-dependent protein kinase II inhibitor KN-93

A novel Ca2+/calmodulin-dependent protein kinase II (CaM Kinase II) inhibitor, KN-93 potently inhibits gastric acid secretion from parietal cells. As previously reported (1), treatment of parietal cells with a selective inhibitor of CaM kinase II, KN-62 resulted in the inhibition of cholinergic-stimulated rabbit parietal cell secretion, whereas it failed to inhibit the histamine and forskolin response. In contrast effects of carbachol, histamine and forskolin were significantly inhibited by KN-93 with an IC50 of 0.15, 0.3 and 1 microM, respectively; these effects occurred without any changes in intracellular cyclic AMP and Ca2+ levels. In the present study we investigated the mechanism by which KN-93 acts upon the acid-secreting machinery of gastric parietal cells. Neither redistribution of the proton pump activity nor the morphological transformation were affected by KN-93. The drug only weakly inhibited the H+, K(+)-ATPase activity but strongly dissipated the proton gradient formed in the gastric membrane vesicles and reduced the volume of luminal space. Thus KN-93 acts at pH gradient formation whereas KN-62 acts only at CaM Kinase II.     

Analysis of the human factor VIII A2 inhibitor epitope by alanine scanning mutagenesis

Antibodies directed to the A2 domain of factor VIII (fVIII) are usually an important component of the polyclonal response in patients who have clinically significant inhibitory antibodies to fVIII. A major determinant of the A2 epitope has been located by homolog scanning mutagenesis using recombinant hybrid human/porcine fVIII molecules to a sequence bounded by Arg484-Ile508 (Healey, J. F. , Lubin, I. M., Nakai, H., Saenko, E. L., Hoyer, L. W., Scandella, D. , and Lollar, P. (1995) J. Biol. Chem. 270, 14505-14509). Within this region, human residues Arg484, Pro485, Tyr487, Ser488, Arg489, Pro492, Val495, Phe501, and Ile508 differ from porcine fVIII. We stably expressed in mammalian cells nine active B-domainless human fVIII molecules containing single alanine substitutions at these sites. Their inhibition by a murine anti-A2 monoclonal antibody, monoclonal antibody (mAb) 413, and by three A2-specific alloimmune and two A2-specific autoimmune human inhibitor plasmas was measured by the Bethesda assay. The inhibition of Arg484 --> Ala, Tyr487 --> Ala, Arg489 --> Ala, and Arg492 --> Ala by mAb413 was reduced by greater than 90% compared with wild-type, B-domainless human fVIII. mAb413 inhibited the most severely affected mutant, Arg489 --> Ala, 0.01% as well as wild-type fVIII. For all five patient plasmas, the Tyr487 --> Ala mutant displayed the greatest reduction in inhibition. The inhibition of the Tyr487 --> Ala mutant by these antibodies ranged from 10% to 20% that of wild-type fVIII. The inhibition of the Ser488 --> Ala, Arg489 --> Ala, Pro492 --> Ala, Val495 --> Ala, Phe501 --> Ala, and Ile508 --> Ala mutants by most of the plasmas also was significantly reduced. In contrast, the Arg484 --> Ala and Pro485 --> Ala mutants were relatively unaffected. Thus, although mAb413 binds to the same region as human A2 inhibitors, it recognizes a different set of amino acid side chains. The side chains recognized by human A2 inhibitors appear to be similar, despite the differing immune settings that give rise to fVIII alloantibodies and autoantibodies.     

水解淫羊藿苷糖基的土壤细菌筛选

从20种土壤细菌中筛选出了对淫羊藿苷水解能力高的菌株Rhodanobncter sp．GS3054．该菌株30℃下发酵3～4d的发酵液提酶后对淫羊藿苷水解能力最佳；水解淫养藿苷成低糖基苷的最适反应条件为：50℃、pH6．0、底物20mg／mL，反应时间24h．