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511.
Wenstrom KD Johanning GL Owen J Johnston KE Acton S Cliver S Tamura T 《American journal of medical genetics》2000,90(1):6-11
A specific gene mutation leading to altered homocysteine metabolism has been identified in parents and fetuses with neural tube defects (NTDs). In addition, current animal and human data indicate that spine closure occurs simultaneously in five separate sites that then fuse. We sought to determine whether either this mutation or abnormal amniotic fluid homocysteine levels are associated with all five neural tube closure sites. We retrieved stored amniotic fluid from cases of isolated fetal neural tube defect diagnosed from 1988 to 1998 (n = 80) and from normal controls matched for race, month and year of amniocentesis, and maternal age. Cases were categorized according to defect site by using all available medical records. The presence or absence of the 677C-->T mutation of 5, 10-methylenetetrahydrafolate reductase (MTHFR) gene was determined, and homocysteine levels were measured; case and controls were compared. Significantly more cases than controls were heterozygous or homozygous for the 677C-->T MTHFR mutation (44% vs. 17%, P < or = 0. 001). Likewise, cases were significantly more likely than controls to have amniotic fluid homocysteine levels >90th centile (>1.85 micromol/L), 27% vs. 10%, P = 0.02. Most (83%) of control cases had both normal MTHFR alleles and normal amniotic fluid homocysteine levels (normal/normal), whereas only 56% of NTD case were normal/normal (P = 0.001). When evaluated by defect site, only defects involving the cervical-lumbar spine, lumbosacral spine, and occipital encephalocele were significantly less likely to be normal/normal than controls (P = 0.007, 0.0003, and 0.007, respectively), suggesting a strong association with the 677C-->T allele. In contrast, anencephaly, exencephaly, and defects confined to the sacrum included many cases that had both normal MTHFR alleles and normal homocysteine and were not significantly different from controls. The 677C-->T MTHFR mutation and elevated homocysteine levels appear to be disproportionately associated with defects spanning the cervical-lumbar spine, lumbosacral spine, and occipital encephalocele. In contrast, anencephaly, exencephaly, and defects confined to the sacrum may not be related to altered homocysteine metabolism. 相似文献
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Background
Obesity/overweight is a recognized risk factor for a host of disorders. The disease risk stratification is commonly based on the Quetelets Index (Body Mass Index- BMI), a surrogate measure of fatness. The currently used BMI cut-offs to classify people as overweight or obese in Armed Forces have been defined in studies on Caucasian populations. However, because of differences in body structure and composition in different ethnic, socioeconomic, cultural and regional groups the correspondence between BMI and body fat content varies between populations. We conducted this pilot study in the Indian Navy to define BMI cut-offs for overweight and obesity using body fat content derived from Skin Fold Thickness as the standard.Material and Methods
The study was conducted on 121 volunteers from a naval hospital staff in the age range of 18 to 47 years. The mean age, height, weight, BMI, body fat in the study group was 26.73 years (± 5.5098), 168.56 cm (± 6.1034), 65.92 Kg (± 10.2746), 23.17 Kg/m2 (± 3.0265) and 19.91% (± 4.831) respectively.Results
The prevalence of overweight/obesity was 20.66% by BMI and 47.11% by body fat content. Receiver operating characteristic (ROC) curve analysis defined a BMI of 23.85 kg/m2 as the cut off for overweight with a sensitivity of 70.2% (95% CI 56.6 – 81.6) and 87.5% specificity (95% CI 76.8-94.4) and a BMI of 24.38 kg/m2with 90% sensitivity (95% CI 68.3-98.5) and 81.2% specificity (95% CI 72.2-88.3) for obesity.Conclusion
The results of our study suggest lower BMI cut offs for overweight and obesity in Indian populations than those recommended by WHO.Key Words: Body Mass Index, Body fat content, Skin fold thickness 相似文献517.
Fungal infections associated with HIV infection 总被引:1,自引:0,他引:1
LP Samaranayake PL Fidel JR Naglik SP Sweet R Teanpaisan MM Coogan E Blignaut P Wanzala 《Oral diseases》2002,8(S2):151-160
Oral candidiasis is perhaps the commonest infection seen in HIV disease. The aim of this workshop was to provide a sketch of the multifarious aspects of the disease from a global perspective. To this end the panellists addressed issues such as the virulence of Candida , emergence of antifungal resistance, management of candidiasis and other exotic, oral mycotic diseases. An all-pervasive theme was the dramatic differences in the management of fungal infections consequential to the availability (or the lack) of anti-HIV drugs in the developed and the developing world. Further, the social stigmata associated with the HIV disease in many developing regions in Africa and Asia appears to modify the therapeutic strategies. Additionally, the lesser-known regional variations in the disease manifestations and therapeutic approaches were stark. Further work is direly needed to address these issues. 相似文献
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背景和目的:对于单用吸入糖皮质激素控制不佳的成人支气管哮喘(简称哮喘)患者,加用长效β-受体激动剂(LABA)可有效改善患者的症状及肺功能.但是最近对LABA长期治疗的安全性受到了美国食品药品管理局(FDA)及部分哮喘专家的质疑.另外,鉴于每个哮喘患者对治疗的反应不尽相同,因此寻求未控制哮喘患者的其他治疗方法是必要的. 相似文献
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ObjectiveTo examine the phytochemical parameters of Aloe vera (A. vera) L. which can be used as a tool for its standardization.MethodsThe phytochemical analysis, solubility test, heavy metal analysis, antimicrobial study and quantitative analysis of gallic acid and berberine by HPTLC method were included in present study.ResultsPhytochemical analysis revealed the presence of alkaloid, carbohydrate, tannin, steroid, triterpenoid and glycoside. Total flavonoid and phenol content was found to be 1.9% and 13.11%. Concentartion of lead, arsenic, mercury and cadmium was found to be under the limit. Total bacterial count, yeast and moulds contents were found to be under the limit whereas Escherichia coli (E. coli) and salmonella was found to be absent in the extract. Quantitative analysis through HPTLC revealed the presence of 2.74% and 0.543% w/w of berberine and gallic acid.ConclusionsThe results indicate that the plant extract are rich in berberine and gallic acid implying their importance to human health. This investigation could be used as source of standard parameters which can play an important role in its standardization. 相似文献