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Susan B. Sisson Peter T. Katzmarzyk Sathanur R. Srinivasan Wei Chen David S. Freedman Claude Bouchard Gerald S. Berenson 《Obesity (Silver Spring, Md.)》2009,17(11):2075-2081
The purpose of this study was to examine ethnic differences in adiposity as measured by sum of skinfolds (SKF) and waist circumference (WC) in children and adolescents, after statistical adjustment for the BMI and age. A cross sectional sample of 3,218 (55% white, 49% male) children and adolescents aged 5–18 years who participated in the Bogalusa Heart Study (1992–1994) were included in these analyses. Sex‐specific ANOVAs, adjusted for BMI and age, for each 2‐year age group compared measures of adiposity (SKF and WC) between ethnic groups. No significant differences in the proportions of children and adolescents who were overweight and obese by ethnicity or sex were found. Mean SKF in normal weight (P < 0.0001) and overweight (P < 0.0001) categories was higher for white than black children of both sexes. Across most age categories, white boys and girls had significantly higher SKF than black boys and girls, respectively (P ≤ 0.05). Across most age categories, white boys had significantly higher WC than black boys (P ≤ 0.05) with no difference in the girls, when adjusted for BMI and age. Measures of adiposity in childhood and adolescence were significantly higher in white children compared to black children, when adjusted for BMI and age. Throughout childhood and adolescence, white boys and girls had higher SKF and white boys had higher WC. Differences in adiposity between ethnic groups should be considered in disease risk assessment and stratification as they are observed even for a given BMI level. 相似文献
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JC Biro 《Theoretical biology & medical modelling》2006,3(1):15-12
Background
Prediction of protein folding and specific interactions from only the sequence (ab initio) is a major challenge in bioinformatics. It is believed that such prediction will prove possible if Anfinsen's thermodynamic principle is correct for all kinds of proteins, and all the information necessary to form a concrete 3D structure is indeed present in the sequence. 相似文献65.
Theron M. Terhune D. Clay Sisson H. Lee Stribling John P. Carroll 《European Journal of Wildlife Research》2006,52(2):119-124
During 1997 and 1998, we compared home range, movement, and site fidelity characteristics of translocated wild northern bobwhite
(Colinus virginianus) to resident birds using radiotelemetry. We captured wild bobwhites (n=74) in southwest Georgia, USA just before the breeding season and relocated them (>1.6 km from capture sites) to sites nearby
where previous density estimates revealed that populations were low compared to surrounding areas. Translocated birds were
equipped with radiotransmitters and released in groups of 8 to 12. Resident birds (n=166) were also captured and simultaneously monitored via radiotelemetry. We found no difference in home range size (F
1=0.08, P=0.78), mean daily movements (F
1=0.04, P=0.84), or distance moved from trap or release sites to arithmetic centers of home ranges (F
1=1.58, P=0.21) between translocated and resident bobwhites. These results suggest that translocating wild bobwhites over relatively
short distances into suitable habitat does not negatively influence bobwhite movement and renders site fidelity as reasonable.
Therefore, translocation of wild bobwhites before breeding season can result in enhanced numbers of adult breeders in a target
location and potentially augments fall populations via reproductive yield. 相似文献
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In this article, we consider the problem of the estimation of quantitative trait loci (QTL), those chromosomal regions at which genetic information affecting some quantitative trait is encoded. Generally the number of such encoding sites is unknown, and associations between neutral molecular marker genotypes and observed trait phenotypes are sought to locate them. We consider a Bayesian model for simple experimental designs, and discuss the existing approaches to inference for this problem. In particular, we focus on locating positions of the best candidate markers segregating for the trait, a situation which is of primary interest in comparative mapping. We introduce a loss function for estimating both the number of QTL and their location, and we illustrate its application via simulated and real data. 相似文献
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The demonstration that interleukin 2 (IL-2) is a lectin specific for
oligomannosides allows to understand a new function for this cytokine: as a
bifunctional molecule when bound to its receptor ss, IL-2 associates the
latter which the CD3/TCR complex, interacting with oligosaccharides of CD3
through its carbohydrate-recognition domain (Zanetta et al. , 1996,
Biochem. J., 318, 49-53). This induces the tyrosine phosphorylation of the
IL-2R beta by ++p56(lck) , the first step of the IL-2-dependent signaling.
Since this specific association is disrupted in vitro by oligomannosides
with five and six mannose residues, we made the hypothesis that pathogenic
cells or microorganisms could bind IL-2, consequently disturbing the IL-2-
dependent response. This study shows that the pathogenic yeast Candida
albicans (in contrast with nonpathogenic yeasts) binds high amounts of IL-2
as did cancer cells. In contrast with cancer cells, yeasts do not bind the
Man6GlcNAc2-specific lectin CSL, an endogenous "amplifier of activation
signals" (Zanetta et al. , 1995, Biochem. J., 311, 629-636).
相似文献
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Effect of insulin on ultrastructure and glycogenesis in primary cultures of adult rat hepatocytes 下载免费PDF全文
Insulin in the presence of high concentrations of glucose has a beneficial trophic effect on the development of primary cultures of hepatocytes. Compared to the situation observed in hormone-free control cultures, the flattening of the reaggregated hepatocytes is enhanced, and the reconstituted cell trabeculae are enlarged and tend to form a confluent monolayer after 3 days; the survival time is prolonged from 3 to 5 or 6 days. Ultrastructural modifications are also initiated by insulin; numerous glycogen particles appear after 24 h, in between the cisternae of the proliferated smooth endoplasmic reticulum. After 48 h, large amounts of glycogen are stored, and numerous polysomes are present. A small number of cells showed an increased synthesis of lipid droplets in the lumen of the smooth endoplasmic reticulum and form liposomes at the same time. After 72 h, cytolysomes filled with glycogen develop, simulating glycogenosis type II. Simultaneously, microtubules and microfilaments, closely related to numerous polysomes, appear in cytoplasmic extensions constituting undulating membranes. The biochemical data demonstrate that, in the absence of insulin, a high concentration of glucose stimulates glycogenesis and hinders glycogenolysis. This effect of glucose on polysaccharide synthesis is progressively lost. The addition of insulin to the culture induces after 48 and 72 h, a three- to fivefold increase of the glucose incorporation into glycogen, as compared to the controls. The presence of insulin is required to maintain the hepatocyte's capacity to store glycogen. Glycogen synthetase is converted into its active form under the influence of glucose. Insulin increases the rate of activation. 相似文献
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