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Visceral fat (VF) promotes the development of metabolic syndrome (MetS), which emerges as early as in adolescence. The clustering of MetS components suggests shared etiologies, but these are largely unknown and may vary between males and females. Here, we investigated the latent structure of pre-clinical MetS in a community-based sample of 286 male and 312 female adolescents, assessing their abdominal adiposity (VF) directly with magnetic resonance imaging. Principal component analysis of the five MetS-defining variables (VF, blood pressure [BP], fasting serum triglycerides, HDL-cholesterol and glucose) identified two independent components in both males and females. The first component was sex-similar; it explained >30% of variance and was loaded by all but BP variables. The second component explained >20% of variance; it was loaded by BP similarly in both sexes but additional loading by metabolic variables was sex-specific. This sex-specificity was not detected in analyses that used waist circumference instead of VF. In adolescence, MetS-defining variables cluster into at least two sub-syndromes: (1) sex-similar metabolic abnormalities of obesity-induced insulin resistance and (2) sex-specific metabolic abnormalities associated with BP elevation. These results suggest that the etiology of MetS may involve more than one pathway and that some of the pathways may differ between males and females. Further, the sex-specific metabolic abnormalities associated with BP elevation suggest the need for sex-specific prevention and treatment strategies of MetS.  相似文献   
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Purified cell walls, originating from penicillin-treated (3 g/ml, 1 h) and-untreated Brevibacterium divaricatum cells grown on complex (CM) and glucose minimal medium with (MM) or without (Ca-free MM) calcium carbonate, were isolated by two procedures. Electron micrographs and chemical analysis revealed no differences between identically isolated walls with respect to the presence or absence of either penicillin or calcium carbonate in the glucose growth medium. On the contrary, the appearance and peptidoglycan content of the walls was greatly dependent on the procedure used for their isolation and the walls isolated from the cells grown on complex medium contained more materials other than peptidoglycan. It was shown that the presence of calcium carbonate in the glucose minimal medium was essential for accumulation of large amounts of peptidoglycan chains into the medium. Penicillin-induced interruption of cell wall synthesis was prerequisite for manifestation of the calcium carbonate stimulating effect.Abbreviations CM complex medium - MM chemically defined minimal medium based on glucose and containing calcium carbonate - Ca-free MM MM modified only by the omission of calcium carbonate - ET-walls Enzyme treated walls - FPR-walls French press-ruptured walls  相似文献   
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DasStellario-Alnetum glutinosae aus Böhmen und Mähren wird in phytozönologischer Hinsicht behandelt. Diese Gesellschaft ist ein periodisch oder episodisch überschwemmter Erlen-Eschen-Auenwald der kollinen Stufe und der niedrigsten Lagen der submontanen Stufe. Nach der Bodenfeuchtigkeit und dem Bodenluftregime wurden die folgenden Subassoziationen unterschieden: 1. dasStellario-Alnetum crepidetosum mit langfristig versumpftem Oberboden und ungünstigem Luftregime des Bodens, 2. dasS.-A. chrysosplenietosum mit nassem bis feuchtem, jedoch nicht versumpftem Oberboden und relativ günstigem Bodenluftregime, 3. dasS.-A. allietosum ursini mit feuchtem bis frischem Oberboden und günstigem Bodenluftregime und 4. dasS.-A. typicum mit feuchtem bis etwas austrocknendem Oberboden und sehr günstigem Bodenluftregime.  相似文献   
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The main aim of this study was to compare the reaction of quiescent and proliferating, i.e. phytohemagglutinin (PHA)-stimulated, human peripheral blood mononuclear cells (PBMCs) to gamma-radiation, and analyse changes of proteins related to repair of DNA damage and apoptosis, such as gammaH2A.X, p53, p53 phosphorylation at serines-15 and -392, and p21 and their dose dependence. Freshly isolated PBMCs in peripheral blood are predominantly quiescent, in G(0) phase, and with very low amounts of proteins p53 and p21. Using confocal microscopy we detected dose dependent (0.5-5 Gy) induction of foci containing gammaH2A.X (1 h after gamma-ray exposure), which are formed around radiation-induced double strand breaks of DNA. Apoptosis was detected from 24 h after irradiation by the dose of 4 Gy onwards by Annexin V binding and lamin B cleavage. Seventy two hours after irradiation 70% of CD3(+) lymphocytes were A(+). Neither increase in p53 nor its phosphorylation on serine-392 after irradiation was detected in these cells. However, massive increase in p21 (cyclin-dependent kinase inhibitor 1A) was detected after irradiation, which can be responsible for late occurrence of apoptosis in these quiescent cells. PHA-stimulation itself (72 h) caused an increase in early apoptosis (A(+)PI(-)) in comparison to non-stimulated PBMCs (38% A(+) resp. 13.4%). After PHA-stimulation also the amount of gammaH2A.X, p53, and p21 increased, but no phosphorylation of p53 on serine-392 or -15 was detected. Reaction to gamma-radiation was different in PHA-stimulated lymphocytes: the p53 pathway was activated and p53 was phosphorylated on serines-15 and -392 4 h after irradiation by the dose of 4 Gy. Phosphorylation of p53 at serine-15 increased in a dose-dependent manner in the studied dose range 0.2-7.5 Gy. Also the amount of p21 increased after irradiation. Seventy two hours after irradiation of PHA-stimulated CD3(+) T lymphocytes by the dose of 4 Gy 65% of cells were A(+).  相似文献   
138.
Trout farming is constantly increasing and poses a serious threat to water quality of clean highland streams. In the present work, we investigated the influence of the farm with the highest trout production in Serbia on water quality and macrozoobenthos communities of the receiving stream, the Trešnjica River. Our study revealed that changes of water chemistry parameters downstream from the trout farm were moderate and mainly confined to the part of the watercourse closest to the wastewater outlet. Moreover, use of food with 0.8% phosphorus content was sufficient to completely eliminate soluble phosphates from water samples of the Trešnjica River. However, the changes in water chemistry were sufficient to cause significant changes in the macrozoobenthos community. These changes remained statistically significant even 500 m downstream and were lost about 3.5 km from the trout farm wastewater effluent. The trout biomass on the farm is a parameter that adequately defines the magnitude of its impact, above all the intensity of its influence on the zoobenthos community structure. The most informative parameters for estimating that influence were the Baetidae/Ephemeroptera ratio, Margelef's index and the Modified biotic index. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
139.
Pectinates with benzyl and decyl ester groups were prepared by alkylation of the tetrabutylammonium salt of pectic acid with benzyl and decyl bromides, respectively. The degree of esterification (DE) of the pectin derivatives was determined by diffuse reflectance infrared Fourier transform spectroscopy and the curve-fitting deconvolution method. A linear relationship between DE and the ratio of the peak area at 1745 cm−1 to the sum of the peak areas at 1745 and 1608 cm−1 was established with a high correlation coefficient 0.98. The deconvolution analysis using the curve-fitting method allowed the elimination of spectral interferences from pectin components and their degradation products. The limits of the method are given by DE 6 and 93%. The method was compared with chemical analysis and found to be equivalent in view of accuracy and repeatability (t-test, F-test). The method is applicable in analysis of natural or synthetic mixtures and/or crude pectin substances.  相似文献   
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