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91.
Association of bone mineral density with a dinucleotide repeat polymorphism at the calcitonin (CT) locus 总被引:3,自引:0,他引:3
Miyao M Hosoi T Emi M Nakajima T Inoue S Hoshino S Shiraki M Orimo H Ouchi Y 《Journal of human genetics》2000,45(6):346-350
Calcitonin (CT), a calcium-regulating hormone, lowers the calcium level in serum by inhibiting bone resorption. Because CT
may play a role in the pathogenesis of osteoporosis, genetic variations in or adjacent to the CT gene may be associated with variations in bone mineral density (BMD). The present study examined the correlation between
a dinucleotide (cytosine-adenine; CA) repeat polymorphism at the CT locus and BMD in 311 Japanese postmenopausal women (mean age, 64.1 years). Seven alleles were present in this population;
each allele contained 10, 11, 16, 17, 18, 19, or 20 CA repeats. Thus, we designated the respective genotypes A10, A11, A16,
A17, A18, A19, and A20. The A10 and A17 alleles were the predominant alleles in the population studied. Z scores (a parameter
representing deviation from the age-specific weight-adjusted average BMD) were compared between individuals that possessed
one or two alleles of each genotype and those that did not possess the allele. Subjects who possessed one or two A10 alleles
had lower BMD Z scores than those who did not (lumbar 2–4 BMD Z score; −0.148 ± 1.23 vs 0.182 ± 1.54; P = 0.04). No significant relationships were observed between allelic status and background data or biochemical parameters.
The significant association observed between BMD and genetic variations at the CT locus implies that polymorphism at this locus may be a useful marker for the genetic study of osteoporosis.
Received: August 10, 2000 / Accepted: September 6, 2000 相似文献
92.
集训新兵躯体化症状特点及其相关因素分析 总被引:5,自引:1,他引:5
目的:探讨集训新兵躯体化症状特点及其相关因素。方法:用成人EPQ和症状自评量表(SCL-90)在集训过程中对1432名新兵进行了躯体化症状和个性评定。结果:集训第一个月末新兵躯体化症状的检出率最高(12.25%),集训第二个月末为9.81%,集训前为8.66%。逐步回归分析表明,影响躯体化症状的主要因素依次为情绪不稳、有过受伤史、缺少体育锻炼、非主动要求参军等。结论:集训期间躯体化症状呈非线性下降趋势,集训前躯体化症状受多种因素影响。 相似文献
93.
Folwaczny M Glas J Török HP Fricke K Folwaczny C 《Clinical immunology (Orlando, Fla.)》2003,109(3):325-329
A 32-base-pair deletion in the CCR5 gene was previously shown to influence the susceptibility for several infectious diseases. The present study compared the frequency of the CCR5-Delta32 mutation among subjects with periodontal disease and healthy control individuals. The prevalence of the CCR5-Delta32 mutation was determined in 81 patients with generalized periodontitis and 121 healthy controls. Standardized clinical and radiographic criteria were used for the diagnosis of periodontitis for each subject. The CCR5-Delta32 mutation was identified by PCR amplification and subsequent agarose gel electrophoresis. Genotype and allele frequencies among both study groups were compared using Fisher's exact test at a level of significance of 5% (P<0.05). The frequency of the CCR5-Delta32 allele was 9.9% (16/162) for periodontitis patients and 10.7% (26/216) for the healthy controls. The allele frequencies between periodontitis patients and the control group for the CCR5-Delta32 mutation were not significantly different (P=0.801). The present study revealed no association between the CCR5-Delta32 mutation and susceptibility to periodontal disease. 相似文献
94.
Objectives: To look for possible association between past history of ovulation induction and age at menopause. Design: Women attending our postmenopausal outpatient clinic were asked to fill questionnaires with demographic data, obstetrical history (including treatment for infertility), and medical details related to menopause. Patients: The study group (n=31) consisted of women with a history of ovulation induction, and a control group (n=200) included women who did not experience such intervention. Results: The age at the final menstrual bleeding was 46.4±5 in the study group, and 50±4 for the control group (P<0.001). This difference was most prominent for women who had induction of ovulation prior to age 35 years: they entered menopause at age 43.8±5 years. Smoking had a weak effect on the age at menopause (48.5±4 for current, vs. 49.9±4 for non- or past-smokers; P<0.03). Conclusions: This retrospective and preliminary study raises the question whether hormonal manipulations and ovarian over-stimulation during fertility treatments could be a risk factor for premature menopause. 相似文献
95.
本文对30年前首次住院经CCMD-2再诊断的203例精神分裂症采用通径分析方法,进行了遗传流行病学对照研究。结果显示精神分裂症的发病与产次、性格、家族史有关。 相似文献
96.
N. Drakoulis I. Cascorbi J. Brockmöller C. R. Gross I. Roots 《Journal of molecular medicine (Berlin, Germany)》1994,72(3):240-248
Genetic differences in the metabolism of carcinogens may codetermine individual predisposition to cancer. Cytochrome P-4501A1 (CYP1A1) metabolically activates precarcinogens in cigarette smoke, such as benzo(a)pyrene, which is also an inducer of CYP1A1. Two point mutations have been reported, m1 in the 3-flanking region (6235T to C), and m2 within exon 7 (4889A to G), the latter leading to an isoleucine to valine exchange. In the Japanese population ml and m2 are correlated with lung cancer, suggesting an increased susceptibility to cigarette smoking related lung cancer. We studied 142 lung cancer and 171 reference patients in an ethnically homogeneous German group for m1 and m2 mutations by restriction fragment length polymorphism and allele-specific polymerase chain reaction, respectively. No statistically significant difference was found in the distribution of m1 alleles between lung cancer and controls; the frequency was 8.5% and 7.3% of the alleles, respectively (odds ratio = 1.17). A trend to an overrepresentation of ml alleles was observed among 52 squamous cell carcinoma patients (odds ratio = 1.65). In contrast, the frequency of m2 alleles in lung cancer patients was twofold higher (6.7%) than in the reference group (3.2%; odds ratio = 2.16; 95% confidence limits 0.96–5.11, P = 0.033); the odds ratio of m2 alleles in squamous cell carcinoma was 2.51 (95% confidence limits 0.85–7.05, P = 0.05). There was a close genetic linkage of m2 to m1 (10 of 11 reference patients), but a significantly higher number of cancer patients showed no linkage compared to the controls (odds ratio = 8.89, 95% confidence limits 0.83–433, P = 0.04). Thus no association was found between presence of ml alleles and lung cancer, but, in contrast, m2 alleles proved as a hereditary risk factor, especially if not linked with m1 alleles.Abbreviations Ah
aryl hydrocarbon
- CYP1A1
cytochrome P4501A1
-
CYP1A1
CYP1A1 gene
- PCR
polymerase chain reaction
- PY
pack years
- RFLP
restriction fragment length polymorphism
Correspondence to: N. Drakoulis 相似文献
97.
An association of 5,10-methylenetetrahydrofolate reductase (MTHFR) gene polymorphism and common carotid atherosclerosis 总被引:3,自引:0,他引:3
Kawamoto R Kohara K Tabara Y Miki T Doi T Tokunaga H Konishi I 《Journal of human genetics》2001,46(9):506-510
Plasma homocysteine (Hcy) concentration has been shown to be influenced by a mutation in the gene coding methylenetetrahydrofolate
reductase (MTHFR). Although plasma Hcy is related to atherosclerotic disorders, conflicting results have been reported about
the association between MTHFR gene polymorphism and sclerotic lesions of the common carotid arteries. The effect of age–gene interaction on carotid arterial
remodeling was investigated in elderly subjects with several risk factors for atherosclerosis. We evaluated sclerotic lesions
of the common carotid arteries by ultrasonography in 326 patients (mean age ± standard deviation, 73 ± 12 years) and studied
relations among the known risk factors for atherosclerosis, including MTHFR gene polymorphism and its interactions with age and sex. Of the 326 subjects studied, 136 had MTHFR genotype CC, 136 genotype CT, and 54 genotype TT. The three groups did not differ with respect to background factors such as age, history of cigarette smoking, blood pressure,
lipids or uric acid, or in the incidence of atherosclerotic diseases. Spearman's rank correlation revealed a significant relationship
between gender, age, Brinkman index, systolic blood pressure, triglycerides, HDL-cholesterol (HDL-C), uric acid, and MTHFR gene polymorphism. Multiple regression analysis using intima-media complex thickness (IMT) as a criterion variable and risk
factors, including MTHFR gene polymorphism as explanatory variables showed that MTHFR gene polymorphism (P = 0.039) was a significant independent explanatory variable for IMT, along with gender (male) (P < 0.001), age (P < 0.001), systolic blood pressure (SBP) (P = 0.047), total cholesterol (T-C) (P < 0.001), and HDL-C (P < 0.001). Furthermore, a general linear model analysis revealed that interaction between age and MTHFR gene polymorphism was significantly associated with IMT, independently of age, SBP, T-C, and HDL-C in male subjects. However,
age–gene interaction was not observed in female subjects. The findings of the present study confirm an association between
MTHFR gene polymorphism and common carotid atherosclerosis in the Japanese population and further support the role of risk factor–gene
interaction in common carotid atherosclerosis.
Received: May 14, 2001 / Accepted: June 8, 2001 相似文献
98.
Factors related to postmenopausal muscle performance: a cross-sectional population-based study 总被引:2,自引:0,他引:2
Sirola J Rikkonen T Kröger H Honkanen R Tuppurainen M Airaksinen O Saarikoski S 《European journal of applied physiology》2004,93(1-2):102-107
The aim of the present study was to investigate cross-sectionally the association of postmenopausal muscle strength with simple performance tests. A random sample of 1,166 naturally postmenopausal women (born 1932–1941) was selected from the Kuopio Osteoporosis Risk Factor and Prevention (OSTPRE) study cohort. Grip and quadriceps strength were measured with strain gauge dynamometers and reported in both absolute values (KPa and kg) and per kilogram of body mass (N cm–2 kg–1 and N kg–1). In addition, two performance tests, ability to stand on one foot and ability to squat down to touch the floor were carried out. A five-category self-assessment of overall health (very good, good, moderate, bad, and very bad) was obtained by postal questionnaire. The women that were able to stand on one foot and able to squat down to touch the floor had greater grip and quadriceps strength than their counterparts (P<0.001 and P<0.03 in ANOVA, respectively). In addition, self-assessed health had a strong positive association with muscle strength in the grip and leg extensor muscles in ANOVA (P<0.001 between very good and moderate or poorer state of health) and regression model (P<0.001). Adjustment for age, duration of menopause, body mass, height, physical activity level, use of HRT, and number of diseases and medications did not change any of the main effects. Also, there were no differences in results between absolute measurement values and values reported per kilogram of body mass. According to the present study, a simple performance test may be useful in the prediction of postmenopausal muscle strength. Furthermore, self-assessed state of health is strongly associated with muscle strength in postmenopausal women. 相似文献
99.
Alzheimer's disease (AD) includes a long asymptomatic stage, which precedes the formal diagnosis of dementia. AD biomarker models provide a framework for precision medicine approaches during this stage. However, such approaches have ignored the possible influence of sex on cognition and brain health, despite female sex noted as a major risk factor. Since AD-related changes may emerge in midlife, intervention efforts are being redirected around this period. Midlife coincides with several endocrinological changes, such as the menopausal transition experienced by women. In this narrative review, we discuss evidence for sex-differences in AD neuropathological burden and outline key endocrinological mechanisms for both sexes, focussing on hormonal events throughout the lifespan that may influence female susceptibility to AD neuropathology and dementia onset. We further consider common non-modifiable (genetic) and modifiable (lifestyle and health) risk factors, highlighting possible sex-dependent differential effects for the AD disease course. Finally, we evaluate the studies selected for this review demonstrating sex-differences in cognitive, pathological and health factors, summarising the state of sex differences in AD risk factors. We further provide recommendations for targeted research on female-specific risk factors, to inform personalised strategies for AD-prevention and the promotion of female brain health. 相似文献
100.
Mustafa al''Absi Susan A. Everson William R. Lovallo 《International journal of psychophysiology》1995,20(3):155-160
Hypertension risk may be associated with increased pressor response to mental stress. However, studies using family history as a predictor of reactivity have obtained mixed results. We assessed cardiovascular responses to mental arithmetic stress (a 5-min serial subtraction task) in male medical students (n = 220) at three levels of hypertension risk based on parental history and the subject's systolic blood pressure (SBP): low (SBP < 125 mm Hg and 0 or 1 hypertensive parent), moderate (resting SBP ≥ 125 mm Hg or 2 hypertensive parents), or high (resting SBP ≥ 125 mm Hg and 1 or 2 hypertensive parents). High risk men showed the greatest blood pressure responses ( + 22/ + 16 mm Hg), while moderate and low-risk groups showed correspondingly smaller responses ( + 17/ + 13 and + 14/ + 11 mm Hg, p's < 0.02). Family history alone did not predict differential reactivity. This study replicates and extends our previous work suggesting the importance of using both family history and resting blood pressure level in determining future risk for hypertension in studies of cardiovascular reactivity in relation to hypertension risk in males. 相似文献