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81.
82.
Objective : To determine the relative validity of specific bioelectrical impedance analysis (BIA) prediction equations and BMI as predictors of physiologically relevant general adiposity. Research Methods and Procedures : Subjects were >12, 000 men and women from the Third National Health and Nutrition Examination Survey population. We examined the correlations between BMI and percentage body fat based on 51 different predictive equations, blood pressure, and blood levels of glucose, high‐density lipoprotein cholesterol, and triglycerides, which are known to reflect adiposity, while controlling for other determinants of these physiological measures. Results : BMI consistently had one of the highest correlations across biological markers, and no BIA‐based measure was superior. Percent body fat estimated from BIA was minimally predictive of the physiological markers independent of BMI. Discussion : These results suggest that BIA is not superior to BMI as a predictor of overall adiposity in a general population. 相似文献
83.
c-Myc and Sp1 contribute to proviral latency by recruiting histone deacetylase 1 to the human immunodeficiency virus type 1 promoter 总被引:1,自引:1,他引:1 下载免费PDF全文
Histone deacetylase (HDAC) inhibitors such as valproic acid (VPA) induce the expression of quiescent proviral human immunodeficiency virus type 1 (HIV-1) and may deplete proviral infection in vivo. To uncover novel molecular mechanisms that maintain HIV latency, we sought cellular mRNAs whose expression was diminished in resting CD4(+) T cells of HIV-1-infected patients exposed to VPA. c-Myc was prominent among genes markedly downregulated upon exposure to VPA. c-Myc expression repressed HIV-1 expression in chronically infected cell lines. Chromatin immunoprecipitation (ChIP) assays revealed that c-Myc and HDAC1 are coordinately resident at the HIV-1 long terminal repeat (LTR) promoter and absent from the promoter after VPA treatment in concert with histone acetylation, RNA polymerase II recruitment, and LTR expression. Sequential ChIP assays demonstrated that c-Myc, Sp1, and HDAC1 coexist in the same DNA-protein complex at the HIV promoter. Short hairpin RNA inhibition of c-Myc reduces both c-Myc and HDAC1 occupancy, blocks c-Myc repression of Tat activation, and increases LTR expression. These results expand the understanding of mechanisms that recruit HDAC and maintain the latency of HIV-1, suggesting novel therapeutic approaches against latent proviral HIV infection. 相似文献
84.
The lesion of nucleus robustus archistriatalis (RA) has no effect on normal short calls in the bramble finch, but affects
significantly the temporal and acoustic features of learned long calls. It causes the principal frequency of basic sound in
monotone long calls to increase 500 cents, and to lose two upper partials. The lesion of RA not only results in the increased
sound length of loud-sound and shortened coda of variable-tone long calls by 13.4%–22.1% and 21.2%–24.2% on average, respectively,
but also makes the frequency rising coefficient (FRC) of even order partial tone in loud-sound drop 18.5%–25.8% on an average,
and the step-up rate decrease 22.7% –24.0% on an average with the increase of frequencies. These results show that the control
of temporal and frequency features of learned calls by RA matches to each other. Moreover, the lesion of bilateral RA can
confuse the vocal pattern, and the produced long call has the character of both the mono- and variable-tone long calls. The
prelude shows rising frequency, and the loud sound is monotone sound. 相似文献
85.
86.
? Here, we studied the poplar C(19) gibberellin 2-oxidase (GA2ox) gene subfamily. We show that a set of paralogous gene pairs differentially regulate shoot and root development. ? PtGA2ox4 and its paralogous gene PtGA2ox5 are primarily expressed in aerial organs, and overexpression of PtGA2ox5 produced a strong dwarfing phenotype characteristic of GA deficiency. Suppression of PtGA2ox4 and PtGA2ox5 led to increased biomass growth, but had no effect on root development. By contrast, the PtGA2ox2 and PtGA2ox7 paralogous pair was predominantly expressed in roots, and when these two genes were RNAi-suppressed it led to a decrease of root biomass. ? The morphological changes in the transgenic plants were underpinned by tissue-specific increases in bioactive GAs that corresponded to the predominant native expression of the targeted paralogous gene pair. Although RNAi suppression of both paralogous pairs led to changes in wood development, they were much greater in the transgenics with suppressed PtGA2ox4 and PtGA2ox5. The degree of gene suppression in independent events was strongly associated with phenotypes, demonstrating dose-dependent control of growth by GA2ox RNA concentrations. ? The expression and transgenic modifications reported here show that shoot- and leaf-expressed PtGA2ox4 and PtGA2ox5 specifically restrain aerial shoot growth, while root-expressed PtGA2ox2 and PtGA2ox7 promote root development. 相似文献
87.
Ando Y Liang Y Ishigaki S Niwa J Jiang Y Kobayashi Y Yamamoto M Doyu M Sobue G 《Neurochemical research》2003,28(6):839-846
Amyotrophic lateral sclerosis is characterized by selective motor neuron degeneration. An apoptotic pathway is thought to be involved. It is difficult, however, to analyze the molecular pathogenic mechanism in single motor neurons because of complexity in the neural tissue, which consists of multiple lineages of cells neighboring motor neurons. We quantified the caspase-1 and -3 mRNA in single motor neurons and neighboring glial cells isolated from the spinal ventral horn of mutant SOD1 transgenic (Tg) mice and littermates. Motor neurons and neighboring glial cells were isolated from spinal sections by laser microdissection, and the mRNAs were quantified by RT-PCR. In the Tg mice, caspase-1 mRNA was first upregulated in motor neurons and second in glial cells. The caspase-3 mRNA was increased in motor neurons following the caspase-1 mRNA. These results indicated that caspase-1 and -3 mRNAs are differentially upregulated in motor neurons and glial cells of the Tg mice, and that mRNAs in isolated cells can be accurately assessed using our procedures. 相似文献
88.
89.
Three spoils from Bold Moss Tip, St. Helens, and one from Neston, England were collected for experiment to find the problems and solutions to reclaim the coal-mine lands of Bold Moss Tip, from seeds and tillers of Agrostis stolonifera, A. capillaris and Hocus lanatus. Low pH (3.0 to 6.8), deficient in nutrient, especially N (0. 24 to 0. 28 ppm), P(0. 016 to 6.1 ppm). and excess of Mg(>1000ppm), Na(84 to 325ppm), and Fe (>20 000ppm)were found in the spoils of Bold Moss Tip, which was supposed to be the most difficult problems of restoration. Tillers of A. stolonifera and A. capillaris could not be planted directly to the bare spoils of Bold Moss Tip, but those of vegetated spoils (Site 2 and Site 3) could support the growth of tillers. The pH value was found to be the key factor to control seed germinations of the three species, below pH 3, there were no germination. A. stolonifera and A. capillaris germinated with the highest rates (97% and 96%) at pH 5 and pH7(p<0. 01)respectively. The application of lime stone could increase spoil pH significantly (p<0. 001), from 2.2 to 7. 3, when 40 t·ha-1 lime stone was added. Lime stone had the best effect to the four spoils. Lime stone +NP significantly increased the yield of dry matters of Site 2 (p<0. 001); The highest yield, 735.6 g · m-1, was gained from the treatment of spoils of Neston with lime stone + N; Lime could also increase the yield of Site 1 from 0 to 125. l g·m-1(p<0. 05). Gypsum had some effect to spoils of Site 2 and Neston, compared with the bland treatment, but did no influence to the spoils of Site 1. Washing had minimum effect toward the spoils of Site 2, and showed no effect to Site 1 and Neston; Throughout the 8-weed% experiment there was little change in the pH of Site 1, even though the spoils were washed everyday. Fertilisers alone had no effect to the bare spoils of Bold Moss Tip, and Neston, but they could enhance the growth of seedling of Site 2, however together with lime stone, the role of fertilisers were significant (p<0. 001). Both nitrogen and phosphorus were essential to the spoils of Bold Moss Tip . Without top-soils, the bare of Bold Moss Tip can be revegetated only by application of lime stone, but better effect coult be obtained by addition of nitrogen and phosphorus. The rates of 20 to 60 t·ha-1, 75 kg N ha-1 and 50 kg P ha-1 of lime stone, nitrogen, phosphorus respectively, are suggested for application. 相似文献
90.
Inflammation may play a major role in the pathogenesis of preeclampsia (PE). In this meta-analysis, we determined whether maternal polymorphisms and serum concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) were associated with PE. All studies investigating the associations between PE and maternal polymorphisms of TNF-α-308G/A, IL-6-174G/C, and IL-10-1082A/G or serum concentrations of TNF-α, IL-6, and IL-10 were reviewed. We found that neither maternal TNF-α-308G/A (p=0.86, odds ratio [OR]=0.98, 95% confidence interval [CI], 0.76-1.25), IL-6 174G/C (p=0.14, OR=1.23, 95% CI, 0.93-1.61), nor IL-10-1082A/G (p=0.72, OR=1.07, 95% CI, 0.75-1.52) were associated with PE. On the other hand, maternal TNF-α (p<0.00001, weighted mean difference [WMD]=19.63 pg/ml, 95% CI, 18.54-20.72 pg/ml), IL-6 (p<0.00001, WMD=6.58 pg/ml, 95% CI, 5.49-7.67 pg/ml), and IL-10 (p=0.0005, WMD=19.30 pg/ml, 95% CI, 8.42-30.17 pg/ml) concentrations were significantly higher in PE patients versus controls. Our findings strengthen the clinical evidence that PE is accompanied by exaggerated inflammatory responses, but do not support TNF-α-308G/A, IL-6-174G/C, and IL-10-1082A/G as candidate susceptibility loci in PE. 相似文献