Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Eight 6-week-old piglets were inoculated with a strain of encephalomyocarditis virus (EMCV) isolated from an outbreak which occurred naturally in the Po Valley in 1988. Two non-infected animals, kept in the same cage, were used as controls. Out of the eight inoculated piglets, two died and two were suppressed on the 2nd post infection day (PID), the four remaining were killed on the 5th, 7th, 11th and 15th PIDs. Control animals were killed at the end of the experiment. The pathogenesis of myocarditis has been studied using routine methods (Alcian-PAS, Masson's trichrome, Gomori's for reticulin and Mallory's stain), histochemical techniques (ATPase and NADH-TR reactions) and ultrastructural observations (TEM). All the inoculated piglets showed macro and/or microscopic lesions of lymphocytic myocarditis, only in one case associated with fibrinous exudation. One control piglet also showed myocarditic lesions, probably due to a contact infection. An early myocardial fibrosis was already present on the 5th PID. Ultrastructurally the cardiac muscle cells showed severe myofibrillar losses and other regressive alterations. Only on the 15th PID did we observe calcification of the degenerating myocytes, while ultrastructurally we detected needle-like calcium deposits in the mitochondria from the 5th PID. From the 5th PID in the areas of myocarditis the myocytes showed a reduction and/or absence of ATPase and NADH-TR reactions. On TEM, one or more aggregates of viral particles in crystalline array were detected in the cytoplasm of many endothelial cells.
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PMID:Ultrastructural study of experimental myocarditis induced by cardiovirus (EMCV-M) in swine. 132 99

The effect on the tegument of adult Fasciola hepatica of incubation in the sodium ionophore monensin, the Na+/K+-ATPase inhibitor ouabain and ouabain pretreatment followed by monensin has been determined in vitro by scanning and transmission electron microscopy (SEM, TEM). With monensin incubation alone (1 x 10(-6) M), a flattening of the tegument with some loss of spines on the ventral surface is evident from 0.5 h onwards. Internally, the subtegumental musculature becomes grossly swollen, although there is no swelling of the infoldings of the basal plasma membrane of the tegument, even after 24 h incubation. Ouabain incubation (1 x 10(-3) M) induces folding of the apical surface of the tegument from 0.5 h onwards, and this is accompanied by the formation of blebs and microvilli. Brief (0.5 h) exposure to ouabain (1 x 10(-3) M) followed by monensin treatment (1 x 10(-4) M, 3 h) leads to gross "vacuolation" of the tegument, but this is not due to swelling of the basal infoldings. The other main feature of ouabain-pretreated flukes is the projection of basal lamina-like material into the tegumental syncytium. Monensin treatment alone (1 x 10(-6) M) results in the Golgi complexes of the tegumental cells becoming very diffuse from 1.5 h onwards, and relatively few secretory bodies are present in the cytoplasm. After 0.5 h incubation in ouabain (1 x 10(-3) M), the Golgi complexes of the tegumental cells are indistinct, although numerous secretory bodies are still present. The classical monensin-induced swelling of the Golgi cisternae is observed in the tegumental cells only when monensin treatment (1 x 10(-4) M, 3 h) was preceded by brief (0.5 h) exposure to ouabain (1 x 10(-3) M). The results are discussed in relation to the postulated osmoregulatory role of the tegument and the role of sodium pumps in membrane function in the fluke.
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PMID:Fasciola hepatica: the effect of the sodium ionophore monensin on the adult tegument. 254 Apr 90

The cytochemical localization of enzymatic activity by means of backscattered electron imaging (BEI) is reviewed and the application of BEI to changes in acid phosphatase and ATPase distribution during physiological (programmed) cell death in Heliothis midgut is explored. Programmed cell death entails the release of nascent free acid phosphatase as extracisternal hydrolase. This shift can readily be detected by means of the atomic number contrast imparted by BEI of the lead phosphatase reaction product, thus enabling the distribution of dying cells to be mapped. BEI is particularly useful in this context as it allows the examination of bulk specimens at low magnification. Death of cells is also accompanied by a collapse in ATPase activity which shows up as cytochemically negative areas in the X-ray microscope and by means of BEI. Acid phosphatase in normal cells is localized in the apical microvilli and lysosomes. Senescent or dying cells, however, clearly show a basally situated free hydrolase which migrates throughout the cell. Parallel TEM results confirm that this enzyme is ribosomal and extracisternal rather than lysosomal in origin. ATPase activity is largely limited to the apical microvilli, although there is some activity associated with the basal plasma membranes. The apical ATPase, however is partially resistant to ouabain. Young and mature cells are positive although in the latter case some microvilli may be lost as the cells acquire a negative cap or dome. Inhibition by bromotetramizole indicates that apical activity is not to any significant extent contributed to by alkaline phosphatase. Degenerate or dead cells are negative and can be seen as a mozaic of "black patches" among normal cells when imaged by means of BEI or X-ray microscopy.
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PMID:The use of backscattered electron imaging, X-ray microanalysis and X-ray microscopy in demonstrating physiological cell death. 297 76

The histochemistry and ultrastructure (SEM and TEM) of the spermatheca of Biomphalaria glabrata was investigated to elucidate the function of this organ and to compare its structure and function to similar organs found in other species. The spermatheca has a debris-filled lumen surrounded by a thin wall of tissue. The cells adjacent to the lumen are of three columnar epithelial cell types. Two cell types have abundant microvilli and mammalian cell-like organelle distribution and morphology. The above cell types differ in the electron density of their cytoplasms, nuclear morphologies, and organelle content. The third cell type differs from the other two in its cytoplasmic makeup. However, the most distinctive difference is the presence of large numbers of cilia at the apical surface with no evidence of microvilli. These columnar cells rest on a basal lamina adjacent to a two to three cell thick muscle layer. The entire organ is surrounded by an adventitia of unusual morphology. Histochemical investigation demonstrated that DNAase, RNAase, and protease are present in the lumen, alkaline phosphatase is associated primarily with the microvilli, small amounts of acid phosphatase are concentrated in the midcell area of the columnar epithelium, and ATPase activity is localized in the muscle cells and just below the absorptive surface of the microvillous cells. The luminal contents and adventitial areas are Sudan Black B positive, all areas of the lumen and organ wall are PAS positive, the cell nuclei and amorphous masses in the lumen showed Feulgen staining, and large vesicles in the columnar cells were Oil Red O positive. Apparently, the spermatheca of B. glabrata is both a digestive and absorptive structure. Although this organ shares functional similarities with those found in opisthobranchs and terrestrial pulmonates, the epithelia of the spermatheca differ dramatically in these groups.
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PMID:Structure and function of the spermatheca in a snail host of schistosomiasis, Biomphalaria glabrata. 364 39

Hairless mouse epidermis was separated from the underlying dermis using a 2 h incubation in 20 mM ethylenediaminetetraacetic acid (EDTA). The basal epidermis, thus exposed, was then examined using scanning electron (SEM), transmission electron (TEM), and light microscopy (LM). Sheets were also stained for: (i) Langerhans cell adenosine triphosphatase (ATPase), beta-glucuronidase, and la antigens; and, (ii) melanocyte 3,4-dihydroxyphenylalanine (DOPA)-oxidase. A regular distribution of protruding dendritic cells was observed superficial to the basal epidermis. These external dendritic cells were identified as Langerhans cells on the basis of subcellular morphology and distribution in the TEM. ATPase staining was Langerhans cell specific. The Langerhans cell population in hairless mouse epidermis was large, and evenly distributed in the interfollicular epidermis and the outer root sheath of degenerate hair follicles. The melanocyte population, in comparison, was negligibly small (4-5 cells per mm2).
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PMID:The Langerhans cell in hairless mouse epidermis. 641 9

A new giant Gram-negative non-cultivatable symbiotic endospore-forming bacterium was found in the gut of the European hamster. This "Metabacterium" sp., provisionally named "Metabacterium criceti", sp. n., has a length of approximately 20 microns and thickness of 4 microns. It forms 1 to 2 cylindrical endospores, approximately 9 microns long and 1.4 microns thick. TEM-micrographs show a cell wall structure characteristic of Gram-negative bacteria. Vegetative cells are filled with granules 0.3 micron in diameter which resemble starch granules. The reproduction occurs with binary fission and by formation of two endospores. Of thirteen biochemical components sought, four, i.e. glycogen, triacylglycerols, peroxidase and alkaline phosphatase, were not found. Starch, acid mucosubstances, DNA, RNA, lipids, proteins, adenosine triphosphatase and acid phosphatase were found in different patterns, depending on the developmental stage of the bacterium. In the vegetative cell stage all these components, with the exception of starch, were found. In the endospore-bearing cell stage, only the starch-like cell component granules could be detected. In free endospores only DNA, RNA and acid phosphatase were found. Some of the components, i.e. DNA, lipids, starch-like granules, were linked to certain cell substructures, the distribution of others, viz. polysaccharides, RNA, adenosine triphosphatase and proteins was diffuse. The lipids, found only in vegetative cells, were associated with the cell wall.
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PMID:Characterization of two Metabacterium sp. from the gut of rodents. 1. Morphology and histochemical examination of a new Metabacterium sp. from the gut of the European hamster (Cricetus cricetus) 769 4

The hematological characteristics of the red-legged partridge are reported. In addition to morphological observations of the circulating blood cells, a hemoglobin (Hb) analysis and cytochemical and ultrastructural observations of the circulating blood cells and their precursors in the bone marrow are presented. Two types of Hb, major and minor, were found. Hemoglobin electrophoresis revealed that they were composed of three different globin chains. On direct examination of the peripheral blood smear, red cells (2.36 x 10(6)/mm3), including 1-3% erythroblasts and rare stem cells; leukocytes (21,000/mm3), and thrombocytes (20-30,000/mm3) were identified. The WBC differential count was: heterophils, 40-70%; basophils, 1-8%; eosinophils, 0-6% %; lymphocytes, 16-50%; and monocytes, 4-11%. On further testing, the heterophilic leukocytes stained with PAS and demonstrated positive reactions for ATPase, ACP, and LAP. Under TEM, their granules appeared elongated and were of uniform density. A crystalline core was not observed. In contrast, the eosinophils contained round granules. B and T lymphocytes were distinguished. The former were identified by the presence of mIgM, the latter by their capacity to form E-rosettes and by the presence of ACP and ALE. Under TEM, the T cells were observed to have microvilli; rare, small granules, and vacuoles. Immunocytochemical techniques were used to identify three platelet factors in the thrombocytes: PF4, FVIIIRAg, and beta-TG.
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PMID:A study of the bone marrow precursors and hemoglobin of the blood cells of the red-legged partridge (Alectoris rufa rufa L.). 801 19

To provide the prerequisite for long-term study of the inner ear related to structural and functional integrity, tissue of stria vascularis with spiral ligament was isolated from Wistar rat cochleas and cultured using the explant-culture technique. The following culture media were used: EMEM with Hepes buffer, hydrocortisone (400 ng/ml), transferrin (5 micrograms/ml). triiodothyronine (10(-9) M), cholera toxin (10(-10) M), insulin (5 micrograms/ml), and epidermal growth factor (10 ng/ml). To characterize the cells growing out from the explant, immunofluorescence with cytokeratin (cytokeratin 18) and ultrastructural examination with SEM and TEM were performed. The marginal cell function was investigated by expression of Na+, K(+)-ATPase antisera against beta 2 subunit of rat Na+, K(+)-ATPase and P-NPPase. We were able to maintain the cultured cells for 3 weeks or more. Monolayered marginal cells were observed beyond 14 days in vitro and the expression of cytokeratin 18 was especially enhanced. The cultured marginal cells were almost identical to in vivo cells both as regards ultrastructural features and Na+, K(+)-ATPase activity. The present results suggest that the primary explant culture technique is a reliable in vitro model of strial marginal cells. However, establishment of the cell line is needed for long-term study.
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PMID:Establishment of primary cell culture from stria vascularis explants. Morphological and functional characterization. 897 11

TolAI--II--beta-lactamase, a fusion protein consisting of the inner membrane and transperiplasmic domains of TolA followed by TEM--beta-lactamase associated with the inner membrane but remained confined to the cytoplasm when expressed at high level in Escherichia coli. Although the fusion protein was resistant to proteolysis in vivo, it was hydrolyzed during preparative SDS-polyacrylamide electrophoresis and when insoluble cellular fractions unfolded with 5 M urea were subjected to microdialysis. Inhibitor profiling studies revealed that both a metallo- and serine protease were involved in TolAI--II--beta-lactamase degradation under denaturing conditions. The in vitro degradation rates of the fusion protein were not affected when insoluble fractions were harvested from a strain lacking protease IV, but were significantly reduced when microdialysis experiments were conducted with material isolated from an isogenic ftsH1 mutant. Adenine nucleotides were not required for degradation, and ATP supplementation did not accelerate the apparent rate of TolAI--II--beta-lactamase hydrolysis under denaturing conditions. Our results indicate that the metalloprotease active site of FtsH remains functional in the presence of 3--5 M urea and suggest that the ATPase and proteolytic activities of FtsH can be uncoupled if the substrate is sufficiently unstructured. Thus, a key role of the FtsH AAA module appears to be the net unfolding of bound substrates so that they can be efficiently engaged by the protease active site.
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PMID:Escherichia coli FtsH (HflB) degrades a membrane-associated TolAI-II-beta-lactamase fusion protein under highly denaturing conditions. 1123 95

One of the important pathways of resistance to anthracyclines is governed by elevated levels of glutathione (GSH) in cancer cells. Resistant cells having elevated levels of GSH show higher expression of multidrug-resistant protein (MRP); the activity of glutathione S-transferases (GSTs) group of enzymes have also been found to be higher in some drug-resistant cells. The general mechanism in this type of resistance seems to be the formation of conjugates enzymatically by GSTs, and subsequent efflux by active transport through MRP (MRP1-MRP9). MRPs act as drug efflux pump and can also co-transport drugs like doxorubicin (Dox) with GSH. Depletion of GSH in resistant neoplastic cells may possibly sensitize such cells, and thus overcome multidrug resistance (MDR). A number of resistance modifying agents (RMA) like DL-buthionine (S, R) sulfoxamine (BSO) and ethacrynic acid (EA) moderately modulate resistance by acting as a GSH-depleting agent. As most of the GSH-depleting agents have dose-related toxicity, development of non-toxic GSH-depleting agent has immense importance in overcoming MDR. The present study describes the resistance reversal potentiality of novel copper complex, viz., copper N-(2-hydroxy acetophenone) glycinate (CuNG) developed by us in Dox-resistant Ehrlich ascites carcinoma (EAC/Dox) cells. CuNG depletes GSH in resistant (EAC/Dox) cells possibly by forming conjugate with it. Depletion of GSH results in higher Dox accumulation that may lead to enhanced rate of apoptosis in EAC/Dox cells. In vivo studies with male Swiss albino mice bearing ascitic growth of EAC/Dox showed tremendous increase in life span (treated/control, T/C = 453%) for the treated group with apparent regression of tumor. Resistance to Dox in EAC/Dox cells is associated with over expression of GST-P1, GST-M1 (enzymes involved in phase II detoxification) and MRP1 (a transmembrane ATPase efflux pump for monoglutathionyl conjugates of xenobiotics). CuNG causes down regulation of all these three proteins in EAC/Dox cells. The effect of CuNG as RMA is better than BSO in many aspects.
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PMID:The role of a novel copper complex in overcoming doxorubicin resistance in Ehrlich ascites carcinoma cells in vivo. 1628 15


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