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281.
Sandbichler AM Farkas J Salvenmoser W Pelster B 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2011,181(8):1023-1034
A primary culture system of rainbow trout gill pavement cells grown on permeable support (single-seeded insert, SSI) was used
to examine histological and physiological changes induced by the addition of the corticosteroid hormone cortisol. Pavement
cell epithelia were cultured under symmetrical conditions (L15 apical/L15 basolateral) and developed a high transepithelial
resistance (TER, 6.84 ± 1.99 kΩ cm2, mean ± SEM) with a low phenol red diffusion rate (PRD, 0.15 ± 0.03 μmol l−1/day). Addition of cortisol to the basolateral compartment increased TER twofold and reduced PRD threefold over a 5-day period.
A similar increase in TER could be seen after 24 h apical freshwater (FW) in control cultures. In cortisol-treated cultures
FW exposure did not change TER, but PRD increased significantly. Histochemical staining of the cytoskeleton of cells in SSI
culture revealed a morphological partitioning into a single mucosal layer of polarized, polygonal cells featuring cortical
F-actin rings which were comparable to F-actin rings of epithelial cells on the lamellar and filamental surface, and several
unorganized serosal layers of cells with F-actin stress fibers. Addition of cortisol increased cell density by 18% and in
the mucosal layer it led to smaller, less polygonal cells with increased height and increased cell contact area. In transmission
electron microscopic images two pairs of cytoplasmatic electron-dense structures confining the zonula occludens apically and basally toward the zonula adhaerens were found. Addition of cortisol increased the distance between those paired structures, hence led to deeper tight junctions.
The cortisol-induced increase in barrier properties, therefore, involves a structural fortification of the tight junctions
which was not generally modified by a short 24-h apical freshwater stress. These results identify cortisol as a regulator
of tight junction morphology between pavement cells of euryhaline fish such as the trout. 相似文献
282.
A Frequent PNPLA3 Variant Is a Sex Specific Disease Modifier in PSC Patients with Bile Duct Stenosis
Kilian Friedrich Christian Rupp Johannes Roksund Hov Niels Steinebrunner Karl-Heinz Weiss Adolf Stiehl Maik Brune Petra Kloeters Yvonne Schaefer Peter Schemmer Peter Sauer Peter Schirmacher Heiko Runz Tom Hemming Karlsen Wolfgang Stremmel Daniel Nils Gotthardt 《PloS one》2013,8(3)
Background & Aims
Primary sclerosing cholangitis predominantly affects males and is an important indication for liver transplantation. The rs738409 variant (I148M) of the PNPLA3 gene is associated with alcoholic and non-alcoholic liver disease and we evaluated its impact on the disease course of PSC.Methods
The I148M polymorphism was genotyped in 121 German PSC patients of a long-term prospective cohort and 347 Norwegian PSC patients.Results
In the prospective German cohort, actuarial survival free of liver transplantation was significantly reduced for I148M carriers (p = 0.011) compared to wildtype patients. This effect was restricted to patients with severe disease, as defined by development of dominant stenosis (DS) requiring endoscopic intervention. DS patients showed markedly decreased survival (p = 0.004) when carrying the I148M variant (I148M: mean 13.8 years; 95% confidence interval: 11.6–16.0 vs. wildtype: mean 18.6 years; 95% confidence interval: 16.3–20.9) while there was no impact on survival in patients without a DS (p = 0.87). In line with previous observations of sex specific effects of the I148M polymorphism, the effect on survival was further restricted to male patients (mean survival 11.9 years; 95% confidence interval: 10.0–14.0 in I148M carriers vs. 18.8 years; 95% confidence interval: 16.2–21.5 in wildtype; p<0.001) while female patients were unaffected by the polymorphism (p = 0.65). These sex specific findings were validated in the Norwegian cohort (p = 0.013).Conclusions
In male PSC patients with severe disease with bile duct stenosis requiring intervention, the common I148M variant of the PNPLA3 gene is a risk factor for reduced survival. 相似文献283.
The strain designated as AB21T was isolated from chloroethylenes contaminated soil. Cells are gram-negative, aerobic, non-spore-forming, and motile rods. Phylogenetic analysis based on 16S rRNA gene sequence showed that it belonged to the genus Rhizobium, and was closely related to Rhizobium sullae IS 123T (97.4 %), Rhizobium yanglingense SH 22623T (97.2 %), Rhizobium gallicum R 602spT (97.1 %), Rhizobium alamii GBV 016T (97.0 %), and Rhizobium monogolense USDA 1844T (97.0 %). It showed less than 97 % identity with the remaining Rhizobium species. This novel isolate grew optimally at 25–37 °C (optimum, 30 °C) and pH 6–9 (optimum, pH 8.0). It grew in the presence of 0–4 % (w/v) NaCl, tolerating a 4 % (w/v) NaCl. DNA–DNA hybridization experiment shows less than 53 % binding with closely related Rhizobium. Predominant quinone is ubiquinone (Q-10). The major fatty acids were summed feature 8 (composed of C18:1 ω7c/C18:1 ω6c), C19:0 cyclo ω8c, and C16:0. The G+C molar content is 62.5 mol%. Based on the polyphasic analysis, strain AB21T is referred to be a novel species of the genus Rhizobium for which the name Rhizobium halotolerans sp. nov. is proposed. The type strain is AB21T (=KEMC 224-056T = JCM 17536T). 相似文献
284.
Adolf Singer 《BMJ (Clinical research ed.)》1983,286(6373):1284-1285
285.
Blood pressure as prognostic marker for body condition,cardiovascular, and metabolic diseases in the common marmoset (Callithrix jacchus)
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286.
Rupert Bliem Sonja Schauer Helga Plicka Adelheid Obwaller Regina Sommer Adolf Steinrigl Munirul Alam Georg H. Reischer Andreas H. Farnleitner Alexander Kirschner 《Applied and environmental microbiology》2015,81(9):3077-3085
Vibrio cholerae is a severe human pathogen and a frequent member of aquatic ecosystems. Quantification of V. cholerae in environmental water samples is therefore fundamental for ecological studies and health risk assessment. Beside time-consuming cultivation techniques, quantitative PCR (qPCR) has the potential to provide reliable quantitative data and offers the opportunity to quantify multiple targets simultaneously. A novel triplex qPCR strategy was developed in order to simultaneously quantify toxigenic and nontoxigenic V. cholerae in environmental water samples. To obtain quality-controlled PCR results, an internal amplification control was included. The qPCR assay was specific, highly sensitive, and quantitative across the tested 5-log dynamic range down to a method detection limit of 5 copies per reaction. Repeatability and reproducibility were high for all three tested target genes. For environmental application, global DNA recovery (GR) rates were assessed for drinking water, river water, and water from different lakes. GR rates ranged from 1.6% to 76.4% and were dependent on the environmental background. Uncorrected and GR-corrected V. cholerae abundances were determined in two lakes with extremely high turbidity. Uncorrected abundances ranged from 4.6 × 102 to 2.3 × 104 cell equivalents liter−1, whereas GR-corrected abundances ranged from 4.7 × 103 to 1.6 × 106 cell equivalents liter−1. GR-corrected qPCR results were in good agreement with an independent cell-based direct detection method but were up to 1.6 log higher than cultivation-based abundances. We recommend the newly developed triplex qPCR strategy as a powerful tool to simultaneously quantify toxigenic and nontoxigenic V. cholerae in various aquatic environments for ecological studies as well as for risk assessment programs. 相似文献
287.
cDNA clones encoding human lysozyme were isolated from a human histiocytic cell line (U-937) and a human placenta cDNA library. The clones, ranging in size from 0.5 to 0.75 kb, were identified by direct hybridization with synthetic oligodeoxynucleotides. The nucleotide sequence coding for the entire protein was determined. The derived amino acid sequence has 100% homology with the published amino acid (aa) sequence; the leader sequence codes for 18 aa. Expression and secretion of human lysozyme in Saccharomyces cerevisiae was achieved by placing the cloned cDNA under the control of a yeast gene promoter (ADH1) and the alpha-factor peptide leader sequence. 相似文献
288.
Sargassum is one of the most species-rich genera in the brown algae with over 400 described species worldwide. The bulk of these species occurs in Pacific-Indian ocean waters with only a small portion found on the Atlantic side of the Isthmus of Panama. Sargassum also has one of the most subdivided and complex taxonomic systems used within the algae. Systematic distinctions within the genus are further complicated by high rates of phenotypic variability in several key morphological characters. Molecular analyses in such systems should allow testing of systematic concepts while providing insights into speciation and evolutionary patterns. Global molecular phylogenetic analyses using both conserved and variable regions of the Rubisco operon ( rbc L and rbc L-IGS-rbcS) were performed with species from the Gulf of Mexico, Caribbean, and Pacific basin. Results confirm earlier analyses based on rbc L-IGS- rbc S from Pacific species at the subgeneric and sectional level while providing additional insights into the systematics and phylogenetics on a global scale. For example, species east of the Isthmus of Panama form a distinct well-resolved clade within the tropical subgenus. This result in sharp contrast to traditional systematic treatments but provides a window into the evolutionary history of this genus in the Pacific and Atlantic Ocean basins and a possible means to time speciation events. 相似文献
289.
290.
Jason E. Adolf Allen R. Place Diane K. Stoecker Lawrence W. Harding 《Journal of phycology》2007,43(6):1259-1270
We examined whether fatty acid (FA) composition changed when Karlodinium veneficum (D. Ballantine) J. Larsen (Dinophyceae) was grown phototrophically or mixotrophically on Storeatula major Butcher ex D. R. A. Hill (Cryptophyceae). We hypothesized that the FA composition of mixotrophic K. veneficum would not change relative to the FA composition of phototrophic K. veneficum. As in other phototrophic dinoflagellates, octadecapentaenoic acid (18:5n3) represented 9% to 20% of total FA in K. veneficum and was enriched within chloroplast‐associated galactolipid classes. The 18:5n3 content showed a highly significant positive correlation (r2 = 0.95) with chl a content and a highly significant negative correlation with growth rate (r2 = 0.88). A previously undescribed chloroplast galactolipid molecular species, digalactosyldiacylglycerol (DGDG; 18:5n3/18:5n3), was a dominant structural lipid in K. veneficum. Docosahexaenoic acid (22:6n3) represented 14% to 19% of total K. veneficum FA and was enriched within phospholipids. In the prey S. major, 18:5n3 was not present, but octadecatetraenoic acid (18:4n3) and α‐linolenic acid (18:3n3) represented approximately 50% of total FA and were enriched within chloroplast‐associated galactolipid classes. Eicosapentaenoic acid (20:5n3) and 22:6n3 represented approximately 18% of total FA in S. major and were enriched within phospholipids. The FA profile of mixotrophic K. veneficum, compared to phototrophic K. veneficum, showed elevated levels of 18:3n3, 18:4n3, and 20:5n3, and lower but persistent levels of 18:5n3. Production to ingestion (P:I) ratios >1 for major polyunsaturated fatty acids (PUFAs) indicated that direct assimilation from prey under balanced growth could not support rates of PUFA production in mixotrophic K. veneficum. These data suggest that the plastid plays a continuing and essential role in lipid metabolism during mixotrophic growth. 相似文献