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Szilvia Bokor Vanessa Legry Aline Meirhaeghe Jonatan R. Ruiz Beatrice Mauro Kurt Widhalm Yannis Manios Philippe Amouyel Luis A. Moreno Dènes Molnàr Jean Dallongeville HELENA Study group 《Obesity (Silver Spring, Md.)》2010,18(7):1398-1403
CD36 is a membrane receptor with a wide variety of functions, including the regulation of energy metabolism, fat storage, and adipocyte differentiation. To assess the relationship between CD36 gene single‐nucleotide polymorphisms (SNPs) and obesity in adolescents, we evaluated the relationship between CD36 SNPs and the risk of obesity in a case–control study composed of 307 obese (age = 15.0 ± 1.1 years) and 339 normal‐weight adolescents (age = 14.6 ± 1.1 years). To validate the results, we assessed the relation between the same SNPs and percentage of body fat (BF%) and BMI in 1,151 European adolescents (age = 14.8 ± 1.4 years). SNPs with a minor allele frequency >0.10 were selected to tag CD36. Genotyping was performed on an Illumina system. Four SNPs (rs3211867, rs3211883, rs3211908, and rs1527483) were associated with increased risk of obesity in the case–control study (odds ratio (OR) (95% confidence interval)): 1.96 (1.26–3.04], P = 0.003; 1.73 (1.16–2.59), P = 0.007; 2.42 (1.47–4.01), P = 0.0005 and 1.95 (1.25–3.05), P = 0.003, respectively). The same four SNPs were associated with higher BMI (P < 0.05) and BF% (P < 0.04) in the validation study. Further analyses identified a haplotype (frequency: 0.05) carrying the minor allele of these SNPs as being associated with obesity (OR: 2.28; P = 0.0008) in the case–control study and with excess adiposity (i.e., higher BF% (P = 0.03) and BMI (P = 0.04)) in the validation study. Our data suggest that genetic variability at the CD36 gene locus could be associated with body weight variability in European adolescents but these findings require replication. 相似文献
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Labile sex expression in plants 总被引:7,自引:0,他引:7
The range of environmental sex determination and sex changes throughout plant taxa from bryophytes and pteridophytes to spermatophytes is reviewed. Lability in sex expression occurs in many plant taxa but only in homosporous pteridophytes is labile sex the rule. Among angiosperms, labile sex appears to be more common among dioecious and monoecious plants than among hermaphrodites. However, hermaphrodites can control allocation to male and female functions by varying the relative emphasis on pollen and ovules. A majority of plants with labile sex expression are perennials, which indicates that flexibility in sex is more important for species with long life cycles. Environmental stress, caused by less-than-optimal light, nutrition, weather or water conditions, often favours maleness. The extreme lability in the sex expression of homosporous pteridophytes is suggested to be related primarily to the mating systems. 相似文献
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We investigated the growth requirements of symbiont-free and symbiont lambda-bearing Paramecium octaurelia stock 299 for folic acid and biopterin in chemically defined culture medium. Symbiont-free P. octaurelia required both folic acid and biopterin for growth. In the absence of these substances growth of symbiont-free P. octaurelia failed after the first transfer, whereas symbiont lambda-bearing P. octaurelia could be maintained indefinitely in serial subculture. In the absence of folic acid and biopterin, sulfanil-amide inhibited growth of the symbiont lambda-beating protozoa. In the presence of folic acid and biopterin, the antiobiotic selectively inhibited growth of lambda symbionts but did not affect growth of the protozoa. In both cases, inhibition by sulfanilamide was reversed by addition of p-aminobenzoic acid to the medium. These results support our earlier finding that folic acid is required for growth of symbiont-free P. octaurelia 299 and that growth of the lambda-bearing strain without exogenous folate denoted synthesis of folic acid by the symbionts. In addition, it appears that the symbionts produce sufficient biopterin to meet the needs of the host protozoon for growth. 相似文献
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MILENA BARCELOS CARDOSO MARIA TERESA SCHIFINO-WITTMANN MARIA HELENA BODANESE-ZANETTINI 《Botanical journal of the Linnean Society. Linnean Society of London》2000,134(4):549-556
Chromosome numbers were determined in 52 individuals of 14 taxa of Leucaena Benth. from 22 populations. For L. cuspidata and L. kmpirana these are the first published chromosome counts. Intraspecific variability was found for L. lempirana, L. macrophjlta and L. shanonii , and one diploid population of the tetraploid species L. pallida was identified. Comparison of our data with those in the literature showed that for L. collinsii and L. macrophylla there is a relationship between chromosome number and subspecies delimitation. The variability detected in chromosome numbers shows the complexity of the diploid and tetraploid species evolution, and suggests multiple origins for some of the polyploid taxa. 相似文献
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Vicente-Rodríguez G Rey-López JP Ruíz JR Jiménez-Pavón D Bergman P Ciarapica D Heredia JM Molnar D Gutierrez A Moreno LA Ortega FB;HELENA Study Group 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(7):2059-2063
The aim of this study was to examine the interrater reliability (trained vs. untrained raters) and criterion-related validity (manual vs. automatic timing) of the 4 × 10-m shuttle run and 30-m running speed tests (times measured). The study comprised 85 adolescents (38 girls) aged 13.0-16.9 years from the Healthy Lifestyle in Europe by Nutrition in Adolescence study. The time required to complete the 4 × 10-m shuttle run and 30-m running tests was simultaneously measured (a) manually with a stopwatch by both trained and untrained raters (for interrater reliability analysis), and (b) by using photoelectric cells (for validity analysis). Systematic error, random error, and heteroscedasticity were studied with repeated-measured analysis of variance and Bland-Altman plots. The systematic error for untrained vs. trained raters and the untrained raters vs. photoelectric cells were in all cases ~0.1 seconds (p < 0.01), that is, untrained raters recorded higher times. No systematic error was found between trained raters and photoelectric cells (p > 0.05). No heteroscedasticity was shown in any case (p > 0.05). The findings indicate that manual measurements by a trained rater, using a stopwatch, seem to be a valid method to assess speed and agility fitness testing in adolescents. Researchers must be trained to minimize the measurement error. 相似文献
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YING HAN YUHUA WANG HAO JIANG MAOLIN WANG HELENA KORPELAINEN CHUNYANG LI 《Plant, cell & environment》2013,36(2):356-364
Drought stress responses and sensitivity of dioecious plants, such as Populus cathayana Rehd., are determined by different mechanisms in each sex. In general, males tend to be more resistant while females are more sensitive. Here, we used reciprocal grafting between males and females to determine the relative importance of roots and shoots when plants are exposed to drought stress. Total dry matter accumulation (DMA), photosynthetic capacity, long‐term water‐use efficiency (Δ), water potential and ultrastructure of mesophyll cells were evaluated to determine the different roles of root and shoot in sex‐related drought responses. Plants with male roots were found to be more resistant and less sensitive to water stress than those with female roots under drought conditions. On the contrary, plants with female shoots grew better than those with male shoots under well‐watered conditions. These results indicated that the sensitivity of males and females to water stress is primarily influenced by root processes, while under well‐watered conditions sexual differences in growth are primarily driven by shoot processes. Furthermore, grafting female shoot scion onto male rootstock was proved to be an effective mean to improve resistance to water stress in P. cathayana females. 相似文献
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HELENA C. BARROS NEWTON V. VERBISCK SOLANGE DA SILVA MARCIA F. ARAGUTH RENATO A. MORTARA 《The Journal of eukaryotic microbiology》1997,44(4):332-344
ABSTRACT. In this study we have examined the distribution of epitopes defined by monoclonal antibodies raised against Trypanosoma cruzi amastigotes during the intraceullar life cycle of the parasite. We have raised monoclonal antibodies towards amastigote forms and performed preliminary immunochemical characterization of their reactivities. MAB 1D9, 3G8, 2B7, 3B9, and 4B9, and 4B9 react with carbohydrate epitopes of the parasite major surface glycoprotein—Ssp-4 defined by MAB 2C2 [5]: MAB 4B5 reacts with a noncarbohydrate epitope in all developmental stages of the parasite, and MAB 3B2 also detects a noncarbohydrate epitope preferentially in T. cruzi flagellared forms. Vero cells infected with tissue culture-derived trypomastigotes of clone D11 (G strain) were fixed at different times during the intraceullular proliferation of parasites, and processed for immjno-electron microscopy and confocal immunoflurescence with the different monoclonal antibodies. We observed that while the surface distribution of MAB 2C2 and 4B9 epitopes was uniform throughout the cycle, MAB 1D9, 3G8, and 2B7 reacted with cytoplasmic membrance-bound compartments of the amastigotes. MAB 3B9 displayed a unique surface dentate pattern in some amastigotes. MAB 4B5 recognized a curved-shaped structure at the flagellar pocket region in some intracellular amastigotes and localized to the membrane in dividing forms. In intracellular trypomastigotes, MAB 4B5 also displayed a punctate pattern near the flagellar pocket. 相似文献
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SUDIPTO CHATTERJEE NEERJA CHOWDHARY SULOCHANA PEDNEKAR ALEX COHEN GRACY ANDREW GRACY ANDREW RICARDO ARAYA GREGORY SIMON MICHAEL KING SHIRLEY TELLES HELENA VERDELI KATHLEEN CLOUGHERTY BETTY KIRKWOOD VIKRAM PATEL 《World psychiatry》2008,7(1):39-46
Common mental disorders, such as depression and anxiety, pose a major public health burden in developing countries. Although these disorders are thought to be best managed in primary care settings, there is a dearth of evidence about how this can be achieved in low resource settings. The MANAS project is an attempt to integrate an evidence based package of treatments into routine public and private primary care settings in Goa, India. Before initiating the trial, we carried out extensive preparatory work, over a period of 15 months, to examine the feasibility and acceptability of the planned intervention. This paper describes the systematic development and evaluation of the intervention through this preparatory phase. The preparatory stage, which was implemented in three phases, utilized quantitative and qualitative methods to inform our understanding of the potential problems and possible solutions in implementing the trial and led to critical modifications of the original intervention plan. Investing in systematic formative work prior to conducting expensive trials of the effectiveness of complex interventions is a useful exercise which potentially improves the likelihood of a positive result of such trials. 相似文献