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991.
Objective: To use longitudinal profiling of plasma adipokines to distinguish diabetogenic vs. non‐diabetogenic obesity syndrome in two new mouse models of polygenic obesity. Research Methods and Procedures: Male mice of the NONcNZO5 strain develop a polygenic obesity syndrome uncomplicated by diabetes, whereas NONcNZO10 males develop a comparable polygenic obesity that precipitates type 2 diabetes. A multiplex immunoassay for simultaneous measurement of insulin and a panel of mouse adipokines (leptin, resistin, adiponectin, interleukin‐6, tumor necrosis factor α, macrophage chemoattractant protein‐1, plasminogen activator inhibitor‐1) were used to profile longitudinal changes in these strains between 4 and 16 weeks of age that might distinguish the non‐diabetogenic vs. diabetogenic obesity (diabesity). Results: Both strains became adipose, with NONcNZO5 males attaining a higher mean body weight with a higher percentage fat content. Weight gain in NONcNZO5 was accompanied by a transient peak in plasma insulin (PI) at 8 weeks followed by a decline into normal range, with normoglycemia maintained throughout. In contrast, NONcNZO10 showed no early PI secretory response because both body weight and plasma glucose increased between 4 and 8 weeks. Only after 12 weeks, with hyperglycemia established, was a delayed PI secretory response observed. Neither plasma leptin nor adiponectin concentrations significantly differentiated the two syndromes over time. However, repeated measures ANOVA showed that NONcNZO10 males maintained significantly higher plasma concentrations of two adipokines, resistin and plasminogen activator inhibitor‐1, and the pro‐inflammatory cytokine/adipokine macrophage chemoattractant protein‐1. Discussion: Longitudinal profiling of PI and adipokines in two new mouse models developing moderate obesity demonstrated that specific marker signatures differentiated a non‐diabetogenic obesity from a diabetogenic obesity.  相似文献   
992.
993.
AimTumor necrosis factor α (TNF-α) influences the pathogenesis of lung-fibrosis and carcinogenesis in normal cells. Polymorphisms of this gene are suggested to be associated with susceptibility to lung-diseases. Additionally TNF-α is postulated to play a significant role in regulating. Transforming growth factor (TGF-β1) expression Therefore we investigated if the TNF-α or TGF-β1 gene expression level is different within the ?308 TNF-α genotypes.MethodsQuantitative Real-time PCR of TNF-α and TGF-β1 was performed in 178 Germans. Calculations of expression were made with the 2?ΔΔCT method. Detection of the ?308 promoter polymorphism of the TNF-α gene was performed by rapid capillary PCR with melting curve analysis.ResultsThe relative TNF-α mRNA expression revealed significant differences between the TNF-α ?308 homozygote wild-type G/G (0.00079 ± 0.00011; n = 113) and the heterozygote genotype G/A (0.0005 ± 0.00008; n = 52; p = 0.030) as well as between homozygote wild-type G/G and the homozygote mutant A/A (0.00029 ± 0.00009; n = 5; p = 0.004). The relative TGF-β mRNA expression showed, similar to TNF-α, the highest mRNA expression was seen within the TNF-α ?308 homozygote wild-types, while the lowest mRNA expression lay within the homozygote mutant-types.ConclusionOur findings suggest that the G-allele of TNF-α ?308 is associated with a significantly higher TNF-α mRNA expression compared to the A-allele and that this also reflects in TGF-β expression. Therefore we support the thesis that TGF-β is regulated by TNF-α.  相似文献   
994.
We found that the androgenic gland (AG) of Macrobrachium rosenbergii possesses three cell types. Type I cells are small polygonal shaped-cells (13.4 μm in diameter), stain strongly with hematoxylin-eosin (H&;E), have abundant multilayered rough endoplasmic reticulum (rER), and nuclei containing mostly heterochromatin. Type II cells are slightly larger (18.6 μm in diameter), stain lightly with H&;E, have rER with dilated cisternae, and nuclei containing mostly euchromatin. Type III cells (previously undescribed) are similar in size and shape to type I cells, but the cytoplasm is unstained and they have a high amount of smooth endoplasmic reticulum (sER) and mitochondria with tubular cristae. Bilateral eyestalk-ablation resulted in AG hypertrophy with a proliferation and predominance of type I cells as determined by bromodeoxyuridine (BrdU) assays. Expression of insulin-like androgenic gland hormone (Mr-IAG), determined by immunohistochemistry, was weak in type I cells, strong in type II cells of both the intact and eyestalk-ablated, and negative in type III cells. It was also detected in spermatogonia, nurse cells, and epithelium lining of the spermatic duct. The function of Mr-IAG in these tissues is yet to be elucidated but the distribution implies a strong role in male reproduction.  相似文献   
995.
Carotenoids, as pigments with antioxidant and immunoregulatory properties, play a crucial role in developing chicks. Carotenoids must be acquired through diet and are relatively scarce, suggesting that their availability is a limiting factor leading to a trade-off between colour displays and physiological functions. However, potential differences in this trade-off between male and female chicks have been little studied. We manipulated carotenoid availability in 9 days old common tern Sterna hirundo chicks by supplementing their fish diet with four carotenoids during 9 days. Our aim was to examine sex-specific responses to the experimental increase of dietary carotenoids on plasma circulation, physiological and condition variables and successful fledging. Furthermore, to explore the functional and evolutionary basis of the trade-off, we studied the relationships among carotenoid concentration, mediated immune response and foot colouration. After treatment, control chicks showed decreasing plasma levels for most carotenoid types, whereas supplemented chicks had strong increases. Colour luminosity and saturation increased in both treatment groups, while hue only changed significantly towards redder feet in supplemented females. Supplemented chicks presented neither different T-cell-mediated immunity nor other differences compared to control chicks. Nevertheless, supplemented females showed tendencies towards decreased immune responses and increased δ15N signatures, and supplemented males towards greater body mass. Our results indicate colouration may have, in females, a signalling function as to compensate for immunological costs. In males, additional availability of carotenoids may contribute to improve the body condition. This study suggests that trade-off responses to carotenoid availability are sex-specific in tern chicks. Thus, parental carotenoid supply to chicks may be an unrecognised component in sex allocation.  相似文献   
996.
We report the rapid acidification of forest soils in the San Bernardino Mountains of southern California. After 30 years, soil to a depth of 25 cm has decreased from a pH (measured in 0.01 M CaCl2) of 4.8 to 3.1. At the 50-cm depth, it has changed from a pH of 4.8 to 4.2. We attribute this rapid change in soil reactivity to very high rates of anthropogenic atmospheric nitrogen (N) added to the soil surface (72 kg ha(-1) year(-1)) from wet, dry, and fog deposition under a Mediterranean climate. Our research suggests that a soil textural discontinuity, related to a buried ancient landsurface, contributes to this rapid acidification by controlling the spatial and temporal movement of precipitation into the landsurface. As a result, the depth to which dissolved anthropogenic N as nitrate (NO3) is leached early in the winter wet season is limited to within the top approximately 130 cm of soil where it accumulates and increases soil acidity.  相似文献   
997.
Establishing the structure of the non-fibrillar collagens has provided a unique perspective to understanding their specialized functions in the extracellular matrix. These proteins exhibit very diverse conformations and supramolecular assemblies. Type XV collagen is a large macromolecule distinguished by a highly interrupted collagenous domain and many utilized sites of attachment for CS (chondroitin sulfate) and HS (heparan sulfate) glycosaminoglycan chains. It is present in most basement membrane zones of human tissues, where it is found closely associated with large collagen fibrils. To determine the molecular shape and organization of type XV, the protein was purified from human umbilical cords by salt extraction, and by ion-exchange and antibody-affinity chromatography. The representation of type XV in one of its most abundant tissue sources is estimated at only (1-2)x10(-4)% of dry weight. The molecules examined by transmission electron microscopy after rotary shadowing were visualized in multiple forms. Relatively few type XV monomers appeared elongated and kinked; most molecules were found in a knot/figure-of-eight/pretzel configuration not previously described for a collagen. Collective measurements of these populations revealed an average length of 193+/-16 nm. At the N-terminal end, identified by C-terminal antibody binding, were three 7.7 nm-diameter spheres, corresponding to TSPN-1 (N-terminal module of thrombospondin-1) modules, and attached to the collagen backbone by a short linker. The type XV monomers show the ability to self-assemble into higher-order structures. Some were arranged in complex clusters, but simpler oligomers, which may represent intermediates, were observed in a cruciform pattern with intermolecular binding sites that probably originate in the interruption sequences. The morphology of type XV is thus the antithesis of the fibrillar collagens, and the shape attains the required flexibility to form the spectrum of interconnecting links between banded fibrils at the basement membrane/interstitial border. These type XV structures may act as a biological 'spring' to stabilize and enhance resilience to compressive and expansive forces, and the multimers, in particular, with selective complements of many localized CS and HS chains, may be instrumental in spatial and temporal recruitment of modulators in growth, development and pathological processes.  相似文献   
998.
Horses frequently suffer from respiratory diseases, which, irrespective of etiology, are often associated with airway mucus accumulation. Studies on human airways have shown that the key structural components of the mucus layer are oligomeric mucins, which can undergo changes of expression and properties in disease. However, there is little information on these gel-forming glycoproteins in horse airways mucus. Therefore, the aims of this study were to isolate equine airways oligomeric mucins, characterize their macromolecular properties, and identify their gene products. To this end, pooled tracheal washes, collected from healthy horses and horses suffering from respiratory diseases, were solubilized with 6 M guanidinium chloride (GdmCl). The oligomeric mucins were purified by density gradient centrifugation followed by size exclusion chromatography. Biochemical and biophysical analyses showed the mucins were stiffened random coils in solution that were polydisperse in size (M(r) = 6-20 MDa, average M(r) = 14 MDa) and comprised of disulfide-linked subunits (average M(r) = 7 MDa). Agarose gel electrophoresis showed that the pooled mucus sample contained at least two populations of oligomeric mucins. Electrospray ionization tandem mass spectrometry of tryptic digests of the unfractionated mucin preparation showed that the oligomeric mucins Muc5b and Muc5ac were present. In summary, we have shown that equine airways mucus is a mixture of Muc5b and Muc5ac mucins that have a similar macromolecular organization to their human counterparts. This study will form the basis for future studies to analyze the contribution of these two mucins to equine airways pathology associated with mucus accumulation.  相似文献   
999.
Summary The chromosome numbers of 11 species ofBiscutella were counted, in 5 species they were found out for the first time.Biscutella laevigata proved to be diploid in some places of Baveria, which are accordingly Submediterranean not Dealpin relicts. Chromosome numbers of n=8, 9 and 18 were counted in Spanish species of the Ser. Laevigatae. By these investigations it was shown that The problem ofBiscutella laevigata (Manton, 1934, 1937) and its allied species is not yet solved, but further cytotaxonomical research may bring forth fundamental results.  相似文献   
1000.
Olsson J  Svanbäck R  Eklöv P 《Oecologia》2007,152(1):48-56
Spatial and temporal heterogeneity in the environment is a common feature affecting many natural populations. For example, both the resource levels and optimal habitat choices of individuals likely change over time. One way for organisms to cope with environmental variation is to display adaptive plasticity in traits such as behavior and morphology. Since trait plasticity is hypothesized to be a prerequisite for character divergence, studies of mechanisms behind such plasticity are warranted. In this study, we looked at the interaction of two potentially important environmental variables on behavioral and morphological plasticity in Eurasian perch (Perca fluviatilis L.). More specifically, the plastic responses in activity and morphology of perch exposed to different resource levels and simulated habitat types were studied in an aquarium experiment. The resource level experienced had a large influence on plasticity in both activity and morphology. Behavioral adaptations have been thought to mediate morphological transitions, and we suggest that the morphological response to the resource level was mediated by differences in activity and growth rates. The habitat type also affected morphological plasticity but to a lesser extent, and there was no effect on activity from habitat type. Based on these results, we suggest that it is essential to include several environmental factors acting in concert when studying mechanisms behind trait plasticity. We also propose that variation in resource levels might play a key role in fostering trait plasticity in at least fish populations, while other environmental variables such as divergent habitat complexities and prey types might be less influential. Dynamics in resource levels and optimal habitat choices might thus be important factors influencing character divergence in natural populations.  相似文献   
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