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Summary

This study examines the relationship between obesity and the increase in serum 25(OH)D levels in response to vitamin D supplementation among adults with baseline serum 25(OH)D levels <50 nmol/L. This study revealed that the increase in serum 25(OH)D in response to vitamin D supplementation was higher in lean subjects as compared to obese subjects.

Introduction

Serum 25(OH)D is lower among obese than non-obese. This study examines the relationship between obesity and the increase in serum 25(OH)D in response to vitamin D supplementation in a large sample of adults with baseline serum 25(OH)D <50 nmol/L, relatively long average treatment duration and large average daily cholecalciferol.

Methods

The computerized database of the Clalit Health Services, which the largest nonprofit health maintenance organization in Israel, was retrospectively searched for all subjects aged ≥20 years who performed serum 25(OH)D test in 2011. Subjects with more than one test at different occasions in 2011 were identified and were included if the result of the first test was <50 nmol/L, and were treated with cholecalciferol between the first and the last test in 2011 (n?=?16,540 subjects).

Results

The mean increase in serum 25(OH)D level after treatment was 28.7 (95 % confidence interval (CI), 28.0–29.4)?nmol/L, 23.6 (23.0–24.2)?nmol/L, and 20.1 (19.6–20.6)?nmol/L in subject with BMI of <25, 25–29.9, and ≥30 kg/m2, respectively (P?<?0.001). The results were similar after adjustment for the potential confounders. Similarly, the proportion of subjects who achieved serum 25(OH)D?≥?50 nmol/L after treatment was inversely associated with BMI; 65.1, 58.3, and 49.1 % for BMI of <25, 25–29.9, and?≥?30 kg/m2, respectively. Compared to BMI of ≥30 kg/m2, the adjusted odds ratio for achieving levels of ≥50 nmol/L were 2.12 (95 % CI, 1.94–2.31) and 1.42 (1.31–1.54) for BMI of <25 kg/m2, and BMI of 25–29.9 kg/m2, respectively.

Conclusions

BMI is inversely associated with the increase in serum 25(OH)D levels in response to vitamin D supplementation.  相似文献   
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Heterogeneity of B cell involvement in acute nonlymphocytic leukemia   总被引:2,自引:0,他引:2  
In order to study the pattern of B cell involvement in acute nonlymphocytic leukemia (ANLL), multiple B lymphoid cell lines were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells from two patients with the disease who were heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD). In one patient, the progenitor cells involved by the leukemia exhibited multipotent differentiative expression, whereas in the other patient the cells showed differentiative expression restricted to the granulocytic pathway. In the patient whose abnormal clone showed multipotent expression, the ratio of B-A G6PD in B lymphoid cell lines was skewed in the direction of type B (the enzyme characteristic of the leukemia clone) and significantly different from the 1:1 ratio expected. It is, therefore, likely that the neoplastic event occurred in a stem cell common to the lymphoid series as well as to the myeloid series. In contrast, evidence for B cell involvement was not detected in the patient whose ANLL progenitor cells exhibited restricted differentiative expression. These findings underscore the heterogeneity of ANLL. Clinically and morphologically similar malignancies in these two patients originated in progenitors with different patterns of stem cell differentiative expression. This difference may reflect differences in cause and pathogenesis.  相似文献   
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Charbord  P; Gown  AM; Keating  A; Singer  JW 《Blood》1985,66(5):1138-1142
The CGA-7, a monoclonal antibody that reacts with smooth muscle cell actin but not with endothelial cell or fibroblast actin, and HHF, a monoclonal antibody that reacts with smooth muscle, skeletal muscle, and cardiac muscle actin, both recognize microfilaments present within adherent cells from actively hematopoietic human long-term marrow cultures. Macrophages, monocytes, and cultured marrow fibroblasts do not react with either antibody. These data suggest that the anti-actin antibodies may serve as useful markers for in vitro microenvironmental cells and lend support to the hypothesis that stromal cells from long- term marrow cultures are different from marrow fibroblasts and may constitute a unique cell lineage.  相似文献   
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Background  

Early and intensive treatment is important to inducing remission and preventing joint damage in patients with rheumatoid arthritis. While intensive combination therapy (Disease Modifying Anti-rheumatic Drugs and/or biologicals) is the most effective, rheumatologists in daily clinical practice prefer to start with monotherapy methotrexate and bridging corticosteroids. Intensive treatment should be started as soon as the first symptoms manifest, but at this early stage, ACR criteria may not be fulfilled, and there is a danger of over-treatment. We will therefore determine which induction therapy is most effective in the very early stage of persistent arthritis. To overcome over-treatment and under-treatment, the intensity of induction therapy will be based on a prediction model that predicts patients' propensity for persistent arthritis.  相似文献   
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The partial liver's ability to regenerate both as a graft and remnant justifies right lobe (RL) living donor liver transplantation. We studied (using biochemical and radiological parameters) the rate, extent of, and predictors of functional and volumetric recovery of the remnant left liver (RLL) during the first year in 91 consecutive RL donors. Recovery of normal liver function (prothrombin time [PT] ≥70% of normal and total bilirubin [TB] ≤20 µmol/L), liver volumetric recovery, and percentage RLL growth were analyzed. Normal liver function was regained by postoperative day's 7, 30, and 365 in 52%, 86%, and 96% donors, respectively. Similarly, mean liver volumetric recovery was 64%, 71%, and 85%; whereas the percentage liver growth was 85%, 105%, and 146%, respectively. Preoperative PT value (p = 0.01), RLL/total liver volume (TLV) ratio (p = 0.03), middle hepatic vein harvesting (p = 0.02), and postoperative peak TB (p < 0.01) were predictors of early functional recovery, whereas donor age (p = 0.03), RLL/TLV ratio (p = 0.004), and TLV/ body weight ratio (p = 0.02) predicted early volumetric recuperation. One‐year post‐RL donor hepatectomy, though functional recovery occurs in almost all (96%), donors had incomplete restoration (85%) of preoperative total liver volume. Modifiable predictors of regeneration could help in better and safer donor selection, while continuing to ensure successful recipient outcomes.  相似文献   
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