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Vitamin D is responsible for multiple metabolic functions in humans. Rickets are the most common disease caused by vitamin D deficiency. It is caused by poor calcium intake resulting in poor serum-ionized calcium. The purpose of this study is to develop a rapid, sensitive, and feasible method to determine the 25-hydroxy-vitamin D3 (25(OH)D3) levels in blood samples for clinical assessment. In this study, gas chromatography coupled mass spectrometry with trimethylsilyl derivatization (TMS-GC-MS) is the most suitable protocol for quantitative analyses of 25(OH)D3. Performance of method was evaluated and compared with liquid chromatography and immunoassay. Method validation has been carried out with plasma specimens. The limit of quantitation of TMS-GC-MS method is 1.5 ppb with good linear correlation. Furthermore, the dietary intake and nutritional status of vegetarian and non-vegetarians in Taiwan were assessed by our validated method. As a result, this vitamin D nutrition survey demonstrates that most Taiwanese people have insufficient vitamin D. Due to dietary habits; the male vegans may have the highest risk of vitamin D deficiency.  相似文献   
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Background

One daily dose of tacrolimus (QDT) improves adherence in kidney transplant (KT) recipients. A switch from twice-daily tacrolimus (BDT) to QDT showed similar efficacy and safety.

Methods

The aim of our study was to demonstrate the long-term efficacy and safety of switching from BDT to QDT in KT recipients. Preliminary results have already been published. Forty-one patients (34 men and 7 women), mean age at KT of 43.9 ± 12.7 years, underwent a 1:1 dose switch from BDT to QDT; the mean time from KT to switch was 36.6 ± 16.1 months. In our study population, 4 patients received a living donor KT and 2 received a second allograft.

Results

The mean follow-up was 86.8 ± 13 months from the switch and 126.2 ± 22.3 months from KT. Graft and patient survival rates were 90.2% and 95.1%, respectively. All patients maintained stable renal function during follow-up. During the first 3 months after the switch we observed a significant decrease in tacrolimus blood level (P = .0001). No significant differences were observed regarding tacrolimus dose before and after QDT introduction (P = not significant [NS]). Fourteen patients who stopped steroids under BDT treatment and 16 patients who stopped steroids after the switch are currently steroid-free.

Conclusion

Our study showed safety and efficacy in switching from BDT to QDT. After early (<1 year) dose adjustment, tacrolimus blood levels remained stable throughout follow-up. Moreover, QDT represented a valid alternative for patients showing steroid side effects.  相似文献   
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The aetiology of vitiligo has not been fully elucidated, and several hypotheses have been investigated; among them, the most explored assumes an autoimmune basis for the disease. Supporting this hypothesis is the frequent co-occurrence of autoimmune diseases with vitiligo. In addition, various genetic loci associated with vitiligo harbour key immune response genes. Our general hypothesis is that autoimmunity-associated genes participate in the control of vitiligo susceptibility. To investigate this hypothesis, we tested for association between vitiligo and genes CYP27B1, REL, TNFAIP3 and IL2/IL21, all previously related to autoimmune diseases associated with vitiligo. The study was performed using two independent population samples: a family-based discovery set (211 trios) and a replication set (131 cases/119 controls). Statistically significant association with vitiligo was detected between markers of the REL and IL2 gene in the family-based sample. Both association signals were concentrated among patients displaying autoimmune comorbidity and non-segmental vitiligo. Evidence for validation was detected for IL2 marker. Our findings suggest REL and IL2 as new vitiligo susceptibility genes and reinforce the hypothesis of a shared genetic mechanism controlling vitiligo and other autoimmune diseases.  相似文献   
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