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71.
Folate and cobalamin deficiencies and hyperhomocysteinemia in Bangladesh   总被引:5,自引:0,他引:5  
BACKGROUND: Indian Asian men residing in the United Kingdom have a higher prevalence of hyperhomocysteinemia than do their European counterparts. This has been largely attributed to dietary deficiencies in cobalamin associated with vegetarianism among these Indian Asians. OBJECTIVE: We aimed to ascertain the prevalence of folate and cobalamin deficiencies and hyperhomocysteinemia in Bangladesh. DESIGN: Plasma concentrations of homocysteine, folate, and cobalamin and urinary concentrations of creatinine were assessed in 1650 adults in Bangladesh. RESULTS: The prevalence of hyperhomocysteinemia (men: >11.4 micromol/L; women: >10.4 micromol/L) was markedly (P < 0.0001) greater among men (63%; x +/- SD: 15.3 +/- 9.5 micromol/L) than among women (26%; 9.5 +/- 4.7 micromol/L). Folate was lower (9.8 +/- 6.5 and 12.3 +/- 7.6 nmol/L, respectively), whereas cobalamin was higher (281 +/- 115 and 256 +/- 118 pmol/L, respectively) (P < 0.0001 for both) among men than among women. Folate explained 15% and cobalamin explained 5% of the variation in homocysteine concentrations. For men, folate (P = 0.005) and cobalamin (P = 0.03) were positively correlated with urinary creatinine. Smoking (P < 0.0003) and betelnut use (P < 0.0002) were independent negative predictors of folate. CONCLUSIONS: Bangladeshi men have a high prevalence of hyperhomocysteinemia, which is more closely associated with folate than with cobalamin, although other factors, eg, smoking and betelnut use, may also contribute to its cause. The positive correlations between urinary creatinine and plasma folate and cobalamin were unanticipated and could suggest that, in marginal nutrition, these vitamins may be limiting for creatine biosynthesis.  相似文献   
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In a series of 36 patients with acute schizophrenia flupenthixol dosage was blindly adjusted to give a fixed level of sedation. Patients were than randomly allocated to procyclidine or placebo. The patients receiving procyclidine experienced more positive schizophrenic symptoms and less severe extrapyramidal features by comparison with placebo patients. Blood levels of prolactin and flupenthixol estimated by radioimmunoassay were not significantly changed by the addition of procyclidine. Flupenthixol dosage and levels and prolactin levels were significantly related. There was no significant association between clinical and laboratory measures, with the exception that a curvilinear (inverted U) relationship was demonstrated between flupenthixol levels and antipsychotic and extrapyramidal effects. This relationship may be due to the fact that, in a study of this design, patients resistant to the effects of neuroleptic medication are likely to be given the highest doses. The findings support earlier claims that anticholinergic medication has adverse effects on schizophrenic symptoms.  相似文献   
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We have reported previously that severe Pagets disease of bone had become less common at our center between 1973 and 1993. Data from several countries support the view that there are important secular trends in the prevalence and severity of Pagets disease. In this paper we describe recent trends in the demography of newly referred patients with Pagets disease to determine if the secular trend toward milder disease has continued. A database of all newly referred patients (n = 1487) with Pagets disease (1973 to 2002 inclusive, 30 years) was examined. Of these, 832 subjects (56%) had scintiscans. Plasma total alkaline phosphatase (total ALP) activity, disease extent on scintiscan, and a derived index of average ALP activity of pagetic bone were used as indices of severity. The number of new referrals with Pagets disease declined sharply from 1994 onward and is currently at half the rate seen 20 years earlier, while the mean age at presentation has progressively increased by 4 years per decade (P < 0.0001). Total ALP at diagnosis, disease extent on scintiscan, and the number of bones involved were all negatively correlated with both date of birth (P < 0.0001) and year of presentation (P < 0.0001), indicating that more recently born and presenting subjects had substantially less severe bone disease. The average activity of pagetic bone was only weakly correlated with year of presentation, but not with year of birth or age at presentation. Although there are a number of potential biases, these data are consistent with a continued secular trend to presentation in older subjects with less extensive skeletal involvement, and a declining prevalence of Pagets disease.  相似文献   
76.
Although carotenoids are known to be important dietary sources of vitamin A, there have been few epidemiological studies that have characterized the serum concentrations of major dietary carotenoids among preschool children with vitamin A deficiency. We conducted a population-based, cross-sectional study of serum pro-vitamin A carotenoids (alpha -carotene, beta-carotene, beta-cryptoxanthin), non-provitamin A carotenoids (lutein/zeaxanthin, and lycopene), and retinol among 278 children, aged 1-5 y, in the Republic of the Marshall Islands. Vitamin A deficiency was defined as serum retinol <0.70 micromol/L. Geometric mean serum concentrations of carotenoids among children with and without vitamin A deficiency were 0.003 vs 0.006 micromol/L for alpha-carotene (P = 0.0017), 0.011 vs 0.023 micromol/L for beta-carotene (P <0.0001), 0.023 vs 0.034 micromol/L for beta-cryptoxanthin (P = 0.0075), 0.007 vs 0.012 micromol/L for lycopene (P = 0.037), 0.044 vs 0.052 micromol/L for lutein/zeaxanthin (P = 0.2), and 0.045 vs 0.074 micromol/L for total provitamin A carotenoids (P <0.0001) respectively. In a multivariate analysis adjusting for sex, age (Odds Ratio [O.R.] 1.44, 95% confidence interval [C.I.] 1.16-1.78), and serum provitamin A carotenoids (O.R. 0.49, 95% C.I. 0.34-0.71) were associated with vitamin A deficiency, but serum non-provitamin A carotenoids were not associated with vitamin A deficiency (O.R. 0.93, 95% C.I. 0.67-1.28). Preschool children with vitamin A deficiency in the Republic of the Marshall Islands have extremely low serum concentrations of provitamin A carotenoids and interventions are needed to improve the dietary intake of provitamin A carotenoids among Marshallese children.  相似文献   
77.
INTRODUCTION: Although vitamin A deficiency, iron deficiency, and inflammation may contribute to anemia, their relative contribution to anemia has not been well characterized in preschool children in developing countries. OBJECTIVE: To characterize the contributions of vitamin A and iron deficiencies and inflammation to anemia among preschool children in the Republic of the Marshall Islands. SUBJECTS AND METHODS: A community-based survey, the Republic of the Marshall Islands Vitamin A Deficiency Study, was conducted among 919 preschool children. The relationship of vitamin A and iron status and markers of inflammation, tumor necrosis factor-alpha, alpha1-acid glycoprotein, and interleukin-10, to anemia were studied in a subsample of 367 children. RESULTS: Among the 367 children, the prevalence of anemia was 42.5%. The prevalence of severe vitamin A deficiency (serum vitamin A < 0.35 micromol/l) and iron deficiency (serum ferritin < 12 microg/dl) were 10.9 and 51.7%, respectively. The respective prevalence of iron deficiency anemia (hemoglobin < 110 g/l and iron deficiency), anemia with inflammation (anemia with TNF-alpha > 2 pg/ml and/or AGP > 1000 mg/l), and severe vitamin A deficiency combined with anemia was 26.7, 35.6, and 7.6%. In multivariate linear regression models that adjusted for age, sex, and inflammation, both iron deficiency (odds ratio (OR) 1.74, 95% confidence interval (CI) 1.08-2.83, P = 0.023) and severe vitamin A deficiency (OR 4.85, 95% CI 2.14-10.9, P < 0.0001) were significantly associated with anemia. CONCLUSIONS: Both iron and vitamin A deficiencies were independent risk factors for anemia, but inflammation was not a significant risk factor for anemia among these preschool children.  相似文献   
78.
Braatvedt GD  Bagg W  Gamble G  Davidson J  Reid IR 《BONE》2004,35(3):766-770
Retrospective and uncontrolled studies suggest that the lipid-lowering statin class of drugs has either no or beneficial effects on bone density and may reduce fracture risk. We have examined the effects of atorvastatin on serum and plasma markers of bone turnover in 25 patients (age 56 +/- 8 years) with type 2 diabetes (duration: 4.7 +/- 5.0 years, 16 female, 2 insulin-treated, 4 diet alone, and 19 on oral hypoglycemic agents) and baseline hypercholesterolemia (cholesterol 6.6 +/- 0.8 mmol/l) in a double-blind, placebo-controlled, crossover study of 12 weeks of placebo/40 mg of atorvastatin with an 8-week wash-out period. Atorvastatin resulted in a fall in total cholesterol of 2.3 +/- 0.9 mmol/l. There were no effects of active or placebo therapy on total alkaline phosphatase, bone-specific alkaline phosphatase, osteocalcin, or beta C-telopeptide of type 1 collagen (beta-CTX). We conclude that atorvastatin (40 mg/day) has no significant effect on bone turnover in man.  相似文献   
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