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BACKGROUND: Adiponectin is a recently discovered plasma protein with many associations to glucose and lipid metabolism. Due to its central role in cardiovascular diseases and insulin resistance, we studied the relationship between serum adiponectin and factors reflecting glucose and lipid metabolism. METHODS AND RESULTS: Thirty healthy participants (20M/10F, age 32.0 +/- 2.1 years, BMI 25.8 +/- 0.9 kg/m (2) and HbA (1c) 5.2 +/- 0.1 %) were studied four times at approximately one week intervals. The effects of a 4-hour euglycemic hyperinsulinemia (40 mU/m (2)/min), saline infusion (control), oral glucose, and oral fat load on serum adiponectin were studied. No significant correlation was found between serum adiponectin and insulin sensitivity before (r = 0.25) or after adjustment for age, BMI and gender (r = 0.04). Adiponectin concentration correlated inversely with HbA (1c) (r = - 0.43, p < 0.05), insulin concentration (r = - 0.38, p < 0.05) and triglyceride concentration (r = - 0.42, p < 0.05) but positively with HDL cholesterol (r = 0.38, p < 0.05). Metabolic procedures had no effect on serum adiponectin. CONCLUSIONS: Our findings favor the interpretation that adiponectin is not causally related to insulin sensitivity in healthy participants. The strongest associations of adiponectin in healthy participants are to be found to lipid metabolism. Serum levels of adiponectin are very stable and not acutely affected by hyperinsulinemia, oral glucose or fat load.  相似文献   
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Lees, J., Märss, T., Wilson, M. V. H., Saat, T. and ?pilev, H. 2011. The sculpture and morphology of postcranial dermal armor plates and associated bones in gasterosteiforms and syngnathiforms inhabiting Estonian coastal waters. ―Acta Zoologica (Stockholm) 93 : 422–435. Five fish species inhabiting Estonian coastal waters (Gasterosteus aculeatus L., Pungitius pungitius (L.), and Spinachia spinachia (L.) of the order Gasterosteiformes and Syngnathus typhle L. and Nerophis ophidion (L.) of the order Syngnathiformes) are described on the basis of the sculpture and morphology of their postcranial dermal armor plates, as revealed and illustrated by SEM images. This study shows that the shapes of these superficial skeletal elements vary by species as well as by their position on the body, whereas the sculpture on the bones is taxon specific. The detailed features allow the identification of isolated fossil and subfossil remains and show promise for future systematics studies.  相似文献   
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Background

Fracture risk is rising in countries undergoing rapid rural to urban migration, but whether this reflects an adverse effect of urbanization on intrinsic bone strength, as reflected by bone mineral density (BMD), is currently unknown.

Methods

Lumbar spine (LS) and total hip (TH) BMD, and total body fat and lean mass, were obtained from DXA scans performed in the Hyderabad arm of the Indian Migration Study (54% male, mean age 49 years). Sib-pair comparisons were performed between rural-urban migrants (RUM) and rural non-migrated (RNM) siblings (N = 185 sib-pairs).

Results

In analyses adjusted for height, gender, age and occupation, rural to urban migration was associated with higher lumbar and hip BMD and greater predicted hip strength; ΔLS BMD 0.030 (0.005, 0.055) g/cm2, ΔTH BMD 0.044 (0.024; 0.064) g/cm2, Δcross-sectional moment of inertia 0.162 (0.036, 0.289) cm4. These differences were largely attenuated after adjusting for body composition, insulin levels and current lifestyle factors ie. years of smoking, alcohol consumption and moderate to vigorous physical activity. Further analyses suggested that differences in lean mass, and to a lesser extent fat mass, largely explained the BMD differences which we observed.

Conclusions

Rural to urban migration as an adult is associated with higher BMD and greater predicted hip strength, reflecting associated alterations in body composition. It remains to be seen how differences in BMD between migration groups will translate into fracture risk in becoming years.  相似文献   
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OBJECTIVE--To investigate the effect of overweight on premature mortality and work disability in young and middle aged Finns. DESIGN--Prospective cohort study based on data collected in the multiphasic health examinations by the Social Insurance Institution of Finland from 1966 to 1972 and follow up until 1982. SETTING--34 Communities throughout Finland. SUBJECTS--12,053 Women and 19,076 men who were employed and aged 25-64 at baseline. MAIN OUTCOME MEASURES--Mortality and work disability pensions from all and specified causes. RESULTS--Body mass index was a weak predictor of death but a strong predictor of early work disability, which increased linearly with body mass index. After adjustment for age, geographical region, occupation, and smoking the relative risks of work disability for women and men with a body mass index greater than or equal to 30 kg/m2 were, respectively, 2.0 (95% confidence interval 1.8 to 2.3) and 1.5 (1.3 to 1.7) when compared with those of subjects with body mass index less than 22.5 kg/m2. The increased risks were due to an excess of cardiovascular and musculoskeletal diseases but not of mental diseases. One fourth of all disability pensions from cardiovascular and musculoskeletal causes in women and half as many in men could be attributed to overweight (body mass index greater than 25 kg/m2) alone. CONCLUSIONS--Though modest overweight has little impact on mortality it predicts severe functional impairment. A considerable proportion of work disability pensions could probably be prevented by efficient weight control.  相似文献   
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The combined stress of high temperature and high relative air humidity is one of the most serious agrometeorological disasters that restricts the production capacity of protected agriculture. However, there is little information about the precise interaction between them on tomato fruit quality. The objectives of this study were to explore the effects of the combined stress of high temperature and relative humidity on the sugar and acid metabolism and fruit quality of tomato fruits, and to determine the best relative air humidity for fruit quality under high temperature environments. Four temperature treatments (32°C, 35°C, 38°C, 41°C), three relative air humidity (50%, 70%, 90%) and four duration (3, 6, 9, 12 d) orthogonal experiments were conducted, with 28°C, 50% as control. The results showed that under high temperature and relative air humidity, the activity of sucrose metabolizing enzymes in young tomato fruits changed, which reduced fruits soluble sugar content; in addition, enzyme activities involved phosphopyruvate carboxylase (PEPC), mitochondria aconitase (MDH) and citrate synthetase (CS) increased which increased the content of organic acids (especially malic acid). Eventually, vitamin C, total sugar and sugar-acid ratio decreased significantly, while the titratable acid increased, resulting in a decrease in fruit flavor quality and nutritional quality in ripe fruit. Specifically, a temperature of 32°C and a relative air humidity of 70% were the best cultivation conditions for tomato reproductive growth period under high temperature. Our results indicating that fruit quality reduced under high temperature at the flowering stage, while increasing the relative air humidity to 70% could alleviate this negative effect. Our results are benefit to better understand the interaction between microclimate parameters under specific climatic conditions in the greenhouse environment and their impact on tomato flavor quality.  相似文献   
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This study investigates the potential effects of moulting, and the concomitant period of fasting undertaken by ringed seals, on hormone, vitamin and contaminant status in adult animals in a population from Svalbard, Norway, which has relatively low contaminant levels. Concentrations of circulating total and free thyroxine and triiodothyronine, circulating and hepatic vitamin A, hepatic persistent organic pollutants and their circulating hydroxyl metabolites were higher in moulting seals compared to pre-moulting seals. The opposite trend was observed for body condition, circulating calcitriol levels and hepatic mRNA expression of thyroid hormone receptor β. No differences were observed for circulating or hepatic vitamin E levels or hepatic mRNA expressions for deioidinase 1 or 2, or retinoic acid receptor α between the two seal groups. The observed differences are likely the result of increased metabolic rates required during moulting to maintain thermal balance and replace the pelage, in combination with mobilization of lipid soluble compounds from blubber stores during the fasting period that is associated with moulting. The present study shows that contaminant levels and their relationships with physiological or endogenous variables can be highly confounded by moulting/fasting status. Thus, moulting status and body condition should be taken into consideration when using variables related to thyroid, calcium or vitamin A homeostasis as biomarkers for contaminant effects.  相似文献   
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