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1.
Polymorphic alleles of CYP17 and CYP19, which are involved in estrogen biosynthesis, were tested for association with breast cancer (BC). Microsatellite (TTTA)n and 3-bp deletion of CYP19 and single-nucleotide polymorphism T27C of CYP17 were analyzed in 123 BC patients and 119 healthy women. Of the six (TTTA)n alleles observed, allele (TTTA)8 proved to be associated with BC (11.8% vs. 6.3%, P = 0.04). Genotype A2/A2 of CYP17 was also associated with BC (32.5% vs. 20.2%, P = 0.04). Risk of BC was especially high in the presence of both factors (7.3% vs. 0%, P < 0.01). Allele (TTTA)8 and genotype A2/A2 were assumed to be risk factors of BC.  相似文献   

2.
The Lean Woman     
Objective: In the current obesity epidemic, the ability to remain lean is beginning to be uncommon. Therefore, it was considered of interest to characterize such subjects. Research Methods and Procedures: From a population of premenopausal women (n = 270), all 40 years of age, those with a similar body mass index (BMI) as women at the age of 21 years, born the same year (BMI = 21.1 kg/m2) were selected among nonsmokers and compared with the remaining nonsmoking women. Results: Lean women showed, as expected, low waist-to-hip circumference ratio and abdominal sagittal diameter as well as absence of other disease risk factors. Compared with the remaining women, 17β-estradiol was high and androgens were low, whereas insulin-like growth factor I and thyroid hormones showed no differences. Dihydroepiandrosterone sulfate was lower, whereas cortisol, measured in saliva repeatedly over a day, and adrenocorticotropin hormone were not different. Results from questionnaires indicated higher education and socioeconomic status, frequent sports activities, and better psychosocial adaptation and psychological health. A tetranucleotide repeat polymorphism in the fifth intron of the aromatase P450 gene was longer among the lean (187 base pairs) than the rest of the women. Women with opposite phylogenetic characteristic have a short microsatellite (168 base pairs) in this gene locus. Discussion: Lean, nonsmoking women enjoy an excellent health in not only anthropometric and metabolic factors, but also in neuroendocrine, endocrine, and psychological variables. The endocrine measurements suggest a well-functioning aromatase, which in turn might have a genetic background, contributing to health. The aromatase gene might be important for regulation of body fat mass.  相似文献   

3.
Objective:To examine whether genetic polymorphisms in CYP19 [intron 4 (TTTA)n; n = 7 to 13 and a 3‐base pair deletion, which is in strong linkage disequilibrium with the seven repeat] and COMT (Val108/158Met) modified the change in BMI, total and percentage body fat, or subcutaneous and intra‐abdominal fat during a year‐long exercise intervention trial. These genes metabolize estrogens and androgens, which are important in body fat regulation. Research Methods and Procedures: A randomized intervention trial was used, with an intervention goal of 225 min/wk of moderate‐intensity exercise for one year. Participants (n = 173) were postmenopausal, 50 to 75 years old, sedentary, overweight or obese, and not taking hormone therapy at baseline. Results: Exercisers with two vs. no CYP19 11‐repeat alleles had a larger decrease in total fat (?3.1 kg vs. ?0.5 kg, respectively, p = 0.01) and percentage body fat (?2.4% vs. ?0.6%, respectively, p = 0.001). Exercisers with the COMT Met/Met vs. Val/Val genotype had a smaller decrease in percentage fat (?0.7% vs. ?1.9%, respectively, p = 0.05). Among exercisers, women with the COMT Val/Val genotype and at least one copy of the CYP19 11‐repeat allele vs. those with neither genotype/allele had a significantly larger decrease in BMI (?1.0 vs. +0.1 kg/m2, respectively, p = 0.009), total fat (?2.9 vs. ?0.5 kg, respectively, p = 0.004), and percentage body fat (?2.6% vs. ?0.4%, respectively, p < 0.001). Discussion: Genetic polymorphisms in CYP19 and COMT may be important for body fat regulation and possibly modify the effect of exercise on fat loss in postmenopausal women.  相似文献   

4.
A genomic cosmid library was used to develop seven highly polymorphic microsatellite markers for the Mexican spotted owl (Strix occidentalis lucida). These are the first reported microsatellite markers derived from this species. The cloned and sequenced repeat motifs include a triplet repeat of (AAT)n, two tetranucleotide repeats of (GATA)n, a tetranucleotide repeat of (ATCC)n, a compound repeat of (GA)n(GATA)n and the two pentanucleotide repeats (AGAAT)n and (ATTTT)n. The microsatellites described represent six presumably independent loci with the two pentanucleotide repeats having originated from a single cosmid. Primer pairs allow locus‐specific amplification of each marker from Mexican spotted owl genomic DNA.  相似文献   

5.
Objective: To examine associations between eating frequency (EF) and body fatness in pre‐ and postmenopausal women, after excluding potential low‐energy reporters. Research Methods and Procedures: In this cross‐sectional study of 220 free‐living women, 64 pre‐ and 50 postmenopausal non‐low‐energy‐reporting women were further analyzed (age, 24 to 74 years; BMI, 18.5 to 38.6 kg/m2). Anthropometric and body composition measurements (DXA) were performed in all study participants. EF, energy, and macronutrient intake were assessed by 3‐day food record. Physical activity level and energy expenditure were assessed by self‐reported questionnaire. Results: No association between EF and adiposity indices was detected in premenopausal women. In contrast, EF was positively correlated with percentage body fat in postmenopausal women (r = 0.30, p = 0.03). EF was positively correlated with total energy intake in both groups and with total energy expenditure in premenopausal women only (r = 0.34, p = 0.02). Multivariate analysis revealed that, in postmenopausal women, EF was a significant predictor of body fatness (standardized β = 0.41, p = 0.01). Discussion: Frequent eating was not found to be related to adiposity in premenopausal women, but it was associated with increased body fat in postmenopausal women. Possible explanations could be that the frequent eating is not associated with a physically active lifestyle in postmenopausal women or that frequent eating predisposes women after menopause to a higher energy intake by increasing food stimuli and rendering it more difficult for them to control energy balance.  相似文献   

6.
Objective: Previous studies have shown that fat metabolism is different in upper body (UB) and lower body (LB) obese women. The present study investigated whether the effect of low‐intensity exercise training on fat metabolism is different in UB and LB obese premenopausal women. Research Methods and Procedures: Twenty‐one healthy, premenopausal women with either LB obesity (waist‐to‐hip ratio of ≤0.79; n = 8) or UB obesity (waist‐to‐hip ratio of ≥0.85; n = 13) participated in the present study. The UB obese women were matched and randomly divided in an exercise training group (UB) and a nonexercising control group (UB‐C). Subjects in the UB and LB groups participated in a low‐intensity exercise training program (40% Vo 2max) three times per week for 12 weeks. Before and after the intervention, measurements of fat metabolism at rest and during exercise, body composition, and maximal aerobic capacity were performed. Results: Exercise training did not change the respiratory exchange ratio at rest in the UB and LB groups. During exercise, relative fat oxidation increased in the UB group by 19% (p < 0.05), whereas no change in the LB and UB‐C groups was found. Plasma free fatty acid oxidation did not change by exercise training, and nonplasma fatty acid oxidation tended to increase in the UB group compared with the UB‐C group (p = 0.08). Discussion: Low‐intensity exercise training increased the contribution of fat oxidation to total energy expenditure during exercise but not at rest in UB obese women. Exercise training had no significant effect on fat metabolism in the LB obese women.  相似文献   

7.
Keller JL  Casson PR  Toth MJ 《Steroids》2011,76(12):1247-1251

Objective

To evaluate the role of physiologic levels of androgens and their precursors in the regulation of body composition, energy and substrate metabolism and aerobic capacity in healthy, cycling, premenopausal women.

Experimental

We evaluated 30 young (27 ± 1 year) premenopausal, non-obese (23 ± 0.5 kg/m2), normally-cycling women, without clinical or chemical evidence of hyperandrogenism or hyperinsulinemia, for parameters of total and regional body composition, glucose tolerance, aerobic capacity and resting energy expenditure and substrate oxidation. Serum was assayed for androgens and androgen precursors by techniques optimized to assess the low androgen levels in this population.

Results

Higher serum testosterone levels correlated with greater fat mass (r = 0.377; p = 0.04), but not abdominal adiposity or other metabolic/physiologic variables. Additionally, dehydroepiandrosterone (DHEA) was negatively related to visceral fat content (r = −0.569; p = 0.02). Other serum androgens did not correlate with total or regional adiposity, skeletal muscle mass, aerobic capacity, glucose tolerance, or resting energy and substrate metabolism.

Conclusion

In this group of non-obese, premenopausal women with no clinical or chemical evidence of hyperandrogenemia, serum testosterone levels were positively related with fat mass, but not with abdominal adiposity; whereas, DHEA was negatively related to visceral adiposity. Our data suggest that within the normal physiologic range, testosterone is a predictor of overall adiposity, but that this effect does not appear to be associated with concomitant alterations in resting energy or substrate metabolism that could predispose to weight gain.  相似文献   

8.
Objectives : To determine the effects of equivalent diet‐ or exercise‐induced weight loss and exercise without weight loss on subcutaneous fat, visceral fat, and insulin sensitivity in obese women. Research Methods and Procedures : Fifty‐four premenopausal women with abdominal obesity [waist circumference 110.1 ± 5.8 cm (mean ± SD)] (BMI 31.3 ± 2.0 kg/m2) were randomly assigned to one of four groups: diet weight loss (n = 15), exercise weight loss (n = 17), exercise without weight loss (n = 12), and a weight‐stable control group (n = 10). All groups underwent a 14‐week intervention. Results : Body weight decreased by ~6.5% within both weight loss groups and was unchanged in the exercise without weight loss and control groups. In comparison with controls, cardiorespiratory fitness improved within the exercise groups only (p < 0.01). Reduction in total, abdominal, and abdominal subcutaneous fat within the exercise weight loss group was greater (p < 0.001) than within all other groups. The reduction in total and abdominal fat within the diet weight loss and exercise without weight loss groups was greater than within controls (p < 0.001) but not different from each other (p > 0.05). Visceral fat decreased within all treatment groups (p < 0.008), and these changes were not different from each other. In comparison with the control group, insulin sensitivity improved within the exercise weight loss group alone (p < 0.001). Discussion : Daily exercise without caloric restriction was associated with substantial reductions in total fat, abdominal fat, visceral fat, and insulin resistance in women. Exercise without weight loss was also associated with a substantial reduction in total and abdominal obesity.  相似文献   

9.
Objective: This study was conducted to obtain a detailed profile of hypothalamo‐pituitary‐adrenal (HPA) axis activity and reactivity and its differential relationships with body fat distribution and total fat mass in premenopausal obese women. Research Methods and Procedures: Cortisol responses to stimulation (awakening, food intake, exercise) and suppression (0.25 mg dexamethasone), cortisol metabolism, and tissue sensitivity to glucocorticoids were studied in 53 premenopausal obese women grouped according to their waist‐to hip ratio: women with abdominal body fat distribution (A‐BFD; n = 31) and women with peripheral fat distribution (P‐BFD; n = 22). Results: Comparatively, A‐BFD women had 1) lower awakening salivary cortisol levels; 2) increased salivary responsiveness to a standardized lunch; 3) similar pituitary sensitivity to dexamethasone but decreased sensitivity of monocytes to dexamethasone; 4) similar 24‐hour urinary free cortisol but increased 24‐hour urinary ratio of cortisone‐to‐cortisol; and 5) no difference in corticosteroid binding protein parameters. Discussion: Although abdominal obesity is not very different from generalized obesity in terms of HPA function, subtle variations in HPA axis activity and reactivity are evidenced in A‐BFD premenopausal obese women.  相似文献   

10.
Objective: There is increasing evidence that depressive mood is associated with central obesity, but little is known about the association between depression and abdominal fat distribution. This study investigated this relationship in premenopausal women. Research Methods and Procedures: We recruited 101 overweight premenopausal women who had no eating disorders as defined using the DSM IV criteria. Depressive mood was assessed using Zung's Self‐Rating Depression Scale (SDS). Areas of visceral (VAT) and subcutaneous (SAT) adipose tissue at the level of vertebral body L4–L5 were measured using computed tomography. Associations of VAT, SAT, and the ratio of VAT to SAT with natural logarithmic transformation [(ln)]SDS were evaluated using linear regression. Anthropometric indices and physical fitness were also measured. Information on socioeconomic status, education level, and alcohol and smoking habits was obtained using self‐administered questionnaires. A hospital nutritionist assessed nutritional status. All of these factors were adjusted for as possible confounding factors in the analyses. Results: The (ln)SDS score showed a positive association with the area of VAT, even after adjusting for the confounders mentioned above (p < 0.01). BMI, waist circumference, maximal oxygen uptake, and age were also associated with the area of VAT (all p < 0.05). In contrast, the (ln)SDS score was not associated with SAT (p > 0.10). Discussion: We showed that depressive mood is associated with VAT, not with SAT, in overweight premenopausal women. These findings may explain some of the association between depression and coronary heart disease. More studies are needed to elucidate the causal relationship.  相似文献   

11.
Using multilocus DNA fingerprinting, we have examined variability of (TCT) n microsatellite and M13 minisatellite DNA repeats in populations, families, and tissues of parthenogenetic Caucasian rock lizards Darevskia unisexualis (Lacertidae). It has been shown for the first time that population and family DNA samples of D. unisexualis (75 samples in total) have individually specific DNA fingerprinting patterns of (TCT) n fragments. Analysis of inheritance of (TCT) n microsatellites in 46 first-generation progeny in 17 parthenogenetic D. unisexualis families revealed their extremely high instability. Mutant TCT fingerprint phenotypes were found in virtually each animal of the progeny. Moreover, varying fragments in the progeny and their original variants in the mothers were shown to simultaneously contain (TCT) n and (TCC) n polypyrimidine clusters. At the same time, no variability of (TCT) n fragments has been detected in the tissues and organs of mature parthenogenetic lizards and in the analogous tissues of the two-week-old progeny of this year. This suggests the absence of somatic mosaicism and methylation of the corresponding loci in the samples. Along with the hyperinstability of (TCT/TCC) n polypyrimidine clusters, we have shown that the population and family DNA fingerprinting patterns of M13 minisatellites were invariable and monomorphic in the same DNA samples of D. unisexualis.Our results indicate that mutations at loci containing polypyrimidine microsatellites significantly contribute to the total genomic variability of parthenogenetic lizards D. unisexualis.  相似文献   

12.
Seven polymorphic tetranucleotide microsatellite loci were isolated and characterized from the black swan Cygnus atratus Latham, using nonradioactive PCR‐based techniques to screen an enriched genomic library. These loci were highly variable (mean H E  = 0.75, mean number of alleles = 9.1), and showed no evidence of linkage disequilibrium or null alleles. This locus set is suitable for detecting extra‐pair copulations (combined exclusion probability = 0.999) and for other population genetic applications.  相似文献   

13.
We report the isolation and characterization of 11 polymorphic tetranucleotide microsatellite loci in the common genet (Genetta genetta) from genomic libraries enriched for (AAAG) n and (AGAT) n repeat sequences. We chose to develop tetranucleotide repeats because they can be scored less ambiguously. In a sample of 25 individuals, we observed between four and thirteen alleles per locus and their observed and expected heterozygosities ranged from 0.60 to 0.84 and from 0.68 to 0.92, respectively. All genotypic frequencies conformed to Hardy–Weinberg equilibrium expectations and there were no instances of linkage disequilibrium detected between pairs of loci. These loci will be of use in studies of population genetics, historical demography, and molecular ecology of the common genet.  相似文献   

14.
Objective: To assess the effects of a “Health‐At‐Every‐Size” (HAES) intervention on eating behaviors and appetite ratings in 144 premenopausal overweight women. Research Methods and Procedures: Women were randomly assigned to one of the 3 groups: HAES group, social support (SS) group, and control group (N = 48 in each group). Interventions were conducted over a 4‐month period, and measurements were taken before and after this period. Eating behaviors (cognitive dietary restraint, disinhibition, and susceptibility to hunger) were evaluated by the Three‐Factor Eating Questionnaire. Appetite ratings (desire to eat, hunger, fullness, and prospective food consumption) were assessed by visual analogue scales before and after a standardized breakfast. Results: More important decreases in susceptibility to hunger and external hunger were observed in the HAES group when compared with the SS group (p = 0.05, for susceptibility to hunger) and the control group (p = 0.02 and p = 0.005, for susceptibility to hunger and external hunger, respectively). In addition, women from the HAES group had more important decreases in postprandial area under the curve for desire to eat (p = 0.02) and hunger (p = 0.04) when compared with the control group. The change in the desire to eat noted in the HAES group was also different from the one observed in SS group (p = 0.02). Women from the HAES group experienced significant weight loss at 4 months (?1.6 ± 2.5 kg, p < 0.0001), which did not differ significantly from the SS and control groups (p = 0.09). An increase in flexible restraint was significantly related to a greater weight loss in both HAES and SS groups (r = ?0.39, p < 0.01; and r = ?0.37, p < 0.05, respectively). A decrease in habitual susceptibility to disinhibition was also associated with a greater weight loss in HAES and control groups (r = 0.31, p < 0.05; and r = 0.44, p < 0.05, respectively). Discussion: These results suggest that a HAES intervention could have significant effects on eating behaviors and appetite ratings in premenopausal overweight women, when compared with an SS intervention or a control group.  相似文献   

15.
Humpback whales wintering in tropical waters along the Atlantic and Pacific coasts of the South American continent are thought to represent distinct populations or “stocks.” Here we present the first analysis of genetic differentiation and estimates of gene flow between these breeding stocks, based on both mitochondrial DNA (mtDNA) control region sequences (465 bp) and 16 microsatellite loci from samples collected off Brazil (n = 277) and Colombia (n = 148), as well as feeding areas near the western Antarctic Peninsula (n = 86). We found significant differentiation between Brazilian and Colombian breeding grounds at both mtDNA (FST = 0.058) and microsatellite (FST = 0.011) markers and corroborated previous studies showing genetic similarity between humpbacks from Colombia and those from Antarctic Peninsula feeding areas. Estimates of long‐term gene flow between Brazil and Colombia were low to moderate, asymmetrical, and mostly mediated by males. Assignment procedures detected some cases of interchange and individuals of admixed ancestry between breeding grounds, indicating limited mixing of individuals between these stocks. Overall, results highlight the differentiation of humpback whale breeding populations with adjacent feeding grounds. This appears to be a remarkable example of fidelity to seasonal habitat in the absence of any contemporary barriers.  相似文献   

16.
While in all vertebrates, growth hormone (GH) promotes post-natal growth, in fishes it also affects such metabolic functions as foraging rate, digestion, osmoregulation, and reproduction. The promoter region of the GH gene is an important target for studies of mechanisms regulating its expression, and polymorphisms within the promoter have been associated with performance traits in fishes. We used Thermal Asymmetric Interlaced PCR (TAIL-PCR) to amplify and sequence the 5′-flanking regions of the Colossoma macropomum GH (cmGH) gene. Based on a sequence of 1,038 bp, we designed three specific nested primers (R-290, R-186 and R-26) which were used with shorter arbitrary degenerate primers to amplify the 5′ proximal region of the cmGH gene. We identified a tetranucleotide (ATCC)4 microsatellite motif in this region, exhibiting four alleles (118, 122, 126 and 130 bp) within the population study. Genotypes at this locus deviated significantly from Hardy–Weinberg expectations (p ≤ .05) and showed a low level of polymorphism (polymorphic information content = 0.163). High homozygosity (FIS = 0.147) was observed in the overall population. The polymorphism at the microsatellite makes it an important candidate for association studies between the respective genotypes, growth rate and other traits in farmed populations. Such studies may contribute to future breeding programs using marker-assisted selection upon this aquaculturally important species.  相似文献   

17.
Objective:To examine bone mass and metabolism in women who had previously undergone Roux‐en‐Y gastric bypass (RYGB) and determine the effect of supplementation with calcium (Ca) and vitamin D. Research Methods and Procedures: Bone mineral density and bone mineral content (BMC) were examined in 44 RYGB women (≥3 years post‐surgery; 31% weight loss; BMI, 34 kg/m2) and compared with age‐ and weight‐matched control (CNT) women (n = 65). In a separate analysis, RYGB women who presented with low bone mass (n = 13) were supplemented to a total 1.2 g Ca/d and 8 μg vitamin D/d over 6 months and compared with an unsupplemented CNT group (n = 13). Bone mass and turnover and serum parathyroid hormone (PTH) and 25‐hydroxyvitamin D were measured. Results:Bone mass did not differ between premenopausal RYGB and CNT women (42 ± 5 years), whereas postmenopausal RYGB women (55 ± 7 years) had higher bone mineral density and BMC at the lumbar spine and lower BMC at the femoral neck. Before and after dietary supplementation, bone mass was similar, and serum PTH and markers of bone resorption were higher (p < 0.001) in RYGB compared with CNT women and did not change significantly after supplementation. Discussion: Postmenopausal RYGB women show evidence of secondary hyperparathyroidism, elevated bone resorption, and patterns of bone loss (reduced femoral neck and higher lumbar spine) similar to other subjects with hyperparathyroidism. Although a modest increase in Ca or vitamin D does not suppress PTH or bone resorption, it is possible that greater dietary supplementation may be beneficial.  相似文献   

18.
We developed 21 microsatellite (13 dinucleotide and 8 tetranucleotide) primers specifically for pumas (Puma concolor). The primers were tested across 243 individuals from California and Nevada, and displayed an average of 5.5 alleles per locus. Previously, domestic cat (Felis catus) primers have been adapted for puma genetic studies. Puma‐specific loci may reduce concerns associated with ascertainment bias, improve genetic structure resolution and provide additional tetranucleotide loci valuable for forensic applications. These puma‐specific microsatellites will aid studies involving parentage, kinship and population structure, along with forensic case applications including poaching and puma‐associated injuries to humans and domestic animals.  相似文献   

19.
To determine the association between the ?265 T to C substitution in the apolipoprotein A‐II (APOA‐II) gene and levels of visceral adipose tissue (VAT) in a group of premenopausal African‐American and white women, we genotyped 237 women (115 African‐American and 122 white) for this polymorphism. Body composition was assessed by DXA, and VAT was determined from a single computed tomography scan. In addition to VAT, we examined the association between the polymorphism and other phenotypes (total body fat, total abdominal adipose tissue, and subcutaneous abdominal adipose tissue). The mutant C allele in the APOA‐II gene was less frequent in African‐American compared with white women, 23% vs. 36%, respectively (p < 0.01). VAT was significantly higher in carriers of the C allele compared with noncarriers after adjustment for total body fat (p < 0.05). When separate analyses by ethnic group were conducted, the association between the polymorphism and VAT was observed in white (p < 0.05) but not African‐American (p = 0.57) women. There was no association between the polymorphism and the other phenotypes. These results indicate a significant association between the T265C APOA‐II polymorphism and levels of VAT in premenopausal women. This association is present in white but not African‐American women.  相似文献   

20.
Objective: To investigate the extent of carotid atherosclerosis and the effect of weight loss on carotid intima‐media thickness (IMT) in obese premenopausal women. Research Methods and Procedures: In 43 obese premenopausal women who participated in a 3‐month weight reduction program with a hypocaloric diet, IMT was measured by B‐mode high‐resolution ultrasound at entry and after 5 months of follow‐up. Blood samples were analyzed at entry, after intervention, and after 5 months of follow‐up. Nineteen lean women served as control subjects. Results: At entry, common carotid IMT (0.72 vs. 0.59 mm), carotid bulb IMT (0.90 vs. 0.71 mm), and overall mean IMT (0.81 vs. 0.65 mm) were greater in obese women than in lean women (all p < 0.01). After dietary intervention decreases in blood pressure, low density lipoprotein to high density lipoprotein cholesterol ratio, triglycerides, fibrinogen, plasminogen activator inhibitor‐1, and an increase in tissue‐type plasminogen activator activity levels were observed. These effects persisted after follow‐up in 14 women who maintained reduced weight. Reduction in carotid bulb IMT (to 0.81 mm, p < 0.01) and overall mean IMT (to 0.79 mm, p < 0.05) was observed in this subgroup. No significant change of carotid IMT was detected in eight women who regained weight. Changes in IMT were associated independently and significantly with changes in body mass index, low density lipoprotein to high density lipoprotein cholesterol ratio, and plasminogen activator inhibitor‐1 antigen. Discussion: Obese premenopausal women had greater IMT than did age‐matched lean controls. It seems that this early atherosclerotic changes may be reversed by normalization of body weight.  相似文献   

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