Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q9UIJ5 (Rec)
 58,342 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A variety of fixatives, buffers and fixation procedures were compared in rat and squirrel monkey lung in an attempt to preserve optimally both the cytologic details of pulmonary parenchyma as well as the acellular avelolar lining layer. In initial experiments utilizing the fixative of Ito and Karnovsky ('68), an electron-dense deposit was observed on the alveolar surface. Experiments were carried out in an attempt to determine what component of this fixative was responsible for the reaction product observed. In addition,immersion fixation of tissue blocks was compared to the whole lung fixation method of Kikkawa ('70). Kikkawa ('70) achieved excellent preservation of the acellular alveolar lining layer by such a fixation technique. In all lungs examined, whenever a phosphate buffer was utilized with primary aldehyde fixation, an electron-dense precipitate was observed on the luminal surfaces of the type I and II pulmonary epithelial cells. Additional sites of reaction product were pinocytotic vesicles of the type I cells and membranous arrays within the alveolar lumen. Such deposits were never observed when a sodium cacodylate buffer was used. No such granules were observed in areas of lung where the acellular alveolar lining layer had been preserved. The implications of these findings with regard to lung histochemical procedures and the possible relationship of these phosphate buffer-dependent granules to the surfactant system are discussed.
Anat Rec 1975 Mar
PMID:The effects of various fixative-buffer combinations on lung fine structure. 4 21

Enriched fractions of chloride cells with good ultrastructural integrity have been obtained from gill filaments of the euyhaline teleost, Lagodon rhomboides. The branchial epithelium from seawater-adapted fish was dissociated by gentle mechanical means in a Ca++, Mg++-free balanced salt solution. Density gradient centrifugation of the mixed cell suspensions through a Ficoll gradient yielded a fraction containing between 50 and 70% chloride cells. This fraction showed a 3- to 4-fold enrichment over comparable gill homogenate values for sodium plus potassium-activated adenosinetriphosphatase, (Na+, K+ ATPase), an enzyme concentrated in chloride cells. Isolation of chloride cells from fish adapted to one-third seawater was less successful, due to the smaller size and reduced number of these cells, although fractions with at least a 2-fold enrichment of the enzyme were obtained. These results continue to support the belief that chloride cells are responsible for osmoregulatory activity associated with the branchial epithelium of teleosts and that this vital function is mediated through the activity of the transport associated enzyme, Na+, K+-ATPase, the specific activity of which increases with osmotic stress.
Anat Rec 1978 Mar
PMID:Rapid isolation of chloride cells from pinfish gill. 14 38

The activity of the electrolyte transport enzyme, sodium, potassium-activated adenosine triphosphatase (Na+,K+-ATPase), in the gills of the pinfish, Lagodon rhomboides, increased markedly following transfer of fish from brackish water to seawater. Cytochemical localization of Na+,K+-ATPase via its potassium-dependent phosphatase (K+-NPPase) activity in the branchial epithelium of pinfish adapted to seawater demonstrated that chloride cells are the major sites for the enzyme. Subcellularly, the heaviest depositions of reaction product were observed lining the cytoplasmic membrane surfaces of the labyrinth of anastomosing plasma membrane tubules that ramifies throughout the chloride cell cytoplasm. Enzyme activity was demonstrated also on the cytoplasmic surface of the apical crypt membrane and on the cytoplasmic surfaces of vesicles in the cytoplasm subjacent to the crypt. Deletion of potassium from the cytochemical incubation medium or inclusion of 10 mM ouabain abolished the reaction products associated with these membranes. The significance of these cytochemical results is discussed with reference to current hypotheses of chloride cell function.
Anat Rec 1979 Jan
PMID:Ultracytochemical localization of Na+,K+-activated ATPase in chloride cells from the gills of a euryhaline teleost. 21 85

Ten calves were challenged with one of two strains of reo-like virus (rotavirus). Changes in the daily faecal and urinary outputs were monitored and packed cell volume, plasma sodium, potassium and urea levels were measured. Faeces were examined for the presence of rotavirus by direct electron microscopy and immunofluorescence in cultures of PK(15) cells. All calves excreted rotavirus in the faeces for several days. Two calves remained clinically normal throughout the experiment, but in the remaining calves, faeces became mucoid in consistency and yellow-white in colour. In only two calves did the daily faecal output exceed 500 g with a fall in the dry matter content to less than 10 per cent. Slightly elevated blood urea levels and hyperkalaemia were the only changes observed in blood chemistry and these quickly returned to normal. Virus antigen was observed in the epithelial cells by immunofluorescence in the proximal and middle small intestine of calves. Pathological lesions occurred predominantly in the proximal small intestine of nine calves examined.
Vet Rec 1979 Mar 10
PMID:Quantitative observations on experimental reo-like virus (rotavirus) infection in colostrum-deprived calves. 22 36

A reliable and uniform vascular perfusion fixation method for the testis has been developed by using an initial washout solution containing a vasodilator and an anticoagulant. This is followed by a brief fixation with a sodium phosphate buffered formaldehyde-glutaraldehyde solution of conventional strenght, and then a second more concentrated aldehyde fixative solution containing picric acid. The method takes into account some of the unique features of the vascular supply of the male genital tract for its favorable perfusion and fixation. The advantages of this method are: (1) consistently favorable preservation of the testis; (2) simple and inexpensive apparatus; and (3) stable and relatively innocuous stock solutions.
Anat Rec 1977 Jul
PMID:An improved perfusion fixation method for the testis. 33 10

Since environmental exposure to arsenicals has been correlated with a high skin cancer risk among populations exposed to sunlight, it is possible that arsenicals might interfere with the repair of damage to DNA (mostly thymine dimers) resulting from the ultraviolet rays in sunlight. To test this hypothesis, strains of E. coli, differing from each other only in one or more repair functions, were exposed to UV light and then plated in the presence or absence of sodium arsenite. Survival after irradiation of wild type E. coli (WP(2)) was significantly decreased by 0.5mM arsenite. This effect was also seen in strains which are unable to carry out excision repair, suggesting that arsenite inhibits one or more steps in the post-replication repair pathways. This is confirmed by the finding that arsenite has no effect on the post-irradiation survival of a recA mutant, which does not carry out post-replication repair. Mutagenesis after ultraviolet irradiation depends on the rec(+) and lex(+) genes. Arsenite decreases mutagenesis in strains containing these genes. In order to determine its mechanism of action, dose-response relationships of arsenite on a number of cellular functions were carried out. The most sensitive cellular functions found were the induction of beta-galactosidase and the synthesis of RNA. Since error-prone repair in E. coli is an inducible process, the inhibition of mutagenesis after UV irradiation may be the result of inhibition of messenger RNA synthesis.
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PMID:Effects of arsenite on DNA repair in Escherichia coli. 33 97

Heavy meromyosin (HMM) labeling was used to identify the nature of the filaments which form bundles in the cytoplasm of the pericytes in brain tissue. Rat brain tissue pieces were incubated in glycerol solutions at 4 degrees and then transferred into buffer (pH 7.0), (1) without HMM, (2) with HMM, (3) with HMM + 5 mM ATP, and (4) with HMM + 2.5 mM Na+ pyrophosphate. In pericytes from untreated tissue, smooth-surfaced microfilaments, averaging 6 nm in diameter, appear to branch and anastomose and to anchor on the plasma membrane. After exposure to HMM, the number and the density of the microfilaments are strikingly increased. These tightly-packed microfilaments are now heavily coated with exogeneous HMM thus increasing in width to 18-20 mm. They intertwine in closely-woven networks. After incubation in HMM solutions containing ATP or Na+ phosphate, they are no longer coated with thick sidearms. It can thus be concluded that these microfilaments are of actin-like nature. In addition, after incubation in ATP, they are intermingled with, and converge onto the surfaces of, thick, tapered filaments, which we have tentatively identified as of myosin-like nature. Thus, it appears that certain of the major elements necessary for contraction are present in brain pericytes.
Anat Rec 1978 Apr
PMID:Actin- and myosin-like filaments in rat brain pericytes. 34 71

Dense crystalline deposits appeared within vacuoles in rat maturative ameloblasts as a result of repeated injections of sodium fluoride. The crystals assumed varied arrangements but were always observed within intracellular vacuoles. The crystals resemble those of normal enamel and resist microincineration. They are readily dissolved by decalcification and leave behind an organic framework which matches the outline of the crystals. An experimental model is presented which may be useful in further studies of calcium transport, enamel matrix absorption or digestion of cellular debris.
Anat Rec 1978 May
PMID:Fluoride-induced mineralization within vacuoles in maturative ameloblasts of the rat. 34 79

Semen samples were collected at weekly intervals for six weeks from eight sexually mature beagles previously shown to produce normal ejaculates. Seminal plasma and sperm fractions were separated by centrifugation and the sodium, potassium, alanine and aspartate aminotransferases, acid and alkaline phosphatase concentrations in the two fractions determined. Regression analysis of the mean weekly values obtained from physical and biochemical examination of the ejaculates showed that sodium ion concentration was highest in seminal plasma. The highest levels of aminotransferases were found in sperm fractions. Those enzymes may be indices of abnormal or damaged spermatozoa. Acid and alkaline phosphatase activity was 100 times greater in seminal plasma than in sperm fractions. Phosphatase concentrations are likely to be dependent on prostate activity. Measurement of acid phosphatase in canine semen therefore may be a useful index of prostate function. The motility of the semen samples was independent of the potassium concentration in seminal plasma. However, there was some evidence of a correlation between sperm motility and the enzyme and sodium content of seminal plasma.
Vet Rec 1979 May 26
PMID:Biochemical observations on beagle dog semen. 47 66

Electron microscopic observations and measurements were made on thin-sectioned chromatin fibers and fibrils obtained from nuclei of mature chicken erythrocytes. The nuclei were isolated in low ionic strength gum arabic and octanol then extracted sequentially with (1) 0.14 M NaCl, (2) 0.25 N HCl, (3) buffer saturated phenol, (4) hot 5% SDS and 0.14 M 2-mercaptoethanol and, (5) 0.4 N NaOH. The amount of nuclear protein removed at each of the first four extraction steps was 1, 86, 3 and 11% of the total, respectively. Each extract was characterized by electrophoretic profiles. At each extraction the chromatin was fixed by adding large quantities of a mixture of equal volumes of sodium cacodylate buffered 8% (w/v) glutaraldehyde (pH 6.8) and 2% OsO4 (w/v), directly into (1) an aliquot of the chromatin in extraction fluid, and (2) an aliquot of the chromatin after water washing and swelling. Three size classes of chromatin structure were seen in thin sections prepared for high resolution transmission electron microscopy and stained with uranyl acetate and lead citrate. A thick fiber of about 25 + nm diameter was the predominant large fiber seen in freshly isolated nuclei or in nuclei after salt extraction. This 25 + nm fiber has a substructure consisting of 3.2-5.2 nm diameter fibrils. After water swelling of such freshly isolated or salt extracted nuclei a fiber of about 10 nm diameter was the predominant large fiber instead of the 25 nm diameter fiber. The HCl extraction step which is known to remove histones, caused the disappearance of both the 25 nm and the 10 nm fibers. High magnification (600,000 x) micrographs of the chromatin at all procedural steps, except the last NaOH step, reveal the fibril to be omnipresent. This fibril tends to decrease somewhat in diameter during the protein extraction steps to a 2.5 nm diameter fibril after the hot SDS extraction. A fibril of 2.5 nm diameter is expected of naked double helical DNA stained with a positive stain. The NaOH, which is known to denature DNA, completely destroyed the remaining fibril. We inerpret our results to indicate that the larger chromatin fiber seen in micrographs of thin-sectioned chromatin has a fibrillar substructure which probably represents a double coil of native DNA which may have a thin protein coating of its own. The latter fibril may in turn be wrapped around a hydrophobic histone domain, perhaps reflected in the 10 nm diameter fiber which is seen upon swelling of the chromatin. This 10 nm diameter fiber is thought to be further packaged by folding into the 25 + nm diameter chromatin fiber most frequently reported in thin sections of eukaryotic cell nuclei in situ.
Anat Rec 1979 Aug
PMID:Chromatin substructure: an electron microscopic study of thin-sectioned chromatin subjected to sequential protein extraction and water swelling procedures. 47 16


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