Assessment of the Role of Serum 25-Hydroxy Vitamin D Level on Coronary Heart Disease Risk With Stratification Among Patients With Type 2 Diabetes Mellitus.

We investigated the role of vitamin D on glycemic regulation and cardiac complications in patients with type 2 diabetes mellitus (T2DM). A total of 1139 patients (49.3% males vs 50.7% females) were included. Information on sociodemographic lifestyle, family history, blood pressure (BP), and coronary heart disease (CHD) complications was collected. Significant differences were found between males and females regarding age-groups (P = .002), body mass index (BMI; P = .008), physical activity (P = .010), sheesha smoking (P = .016), cigarette smoking (P = .002), hypertension (P = .050), metabolic syndrome (P = .026), and CHD (P = .020). There were significant differences between vitamin D deficiency, insufficiency, and sufficiency in relation to age-group (P = .002), income (P = .002), waist circumference (P = .002), hip circumference (P = .028), waist-hip ratio (P = .002), and BMI (P = .002). Further, mean values of hemoglobin, magnesium, creatinine, hemoglobin A1c (HbA1c), total cholesterol, uric acid, and diastolic BP were significantly higher among patients with vitamin D deficiency compared with those with insufficiency and sufficiency. Multiple logistic regression analysis revealed that 25-hydroxy vitamin D, 25(OH)D, HbA1c, waist circumference, uric acid, duration of T2DM, total cholesterol, systolic and diastolic BP, and BMI were strong predictor risk factors for CHD among patients with T2DM. The present study supports that 25(OH)D may have a direct effect on CHD and on its risk factors.

Quantitative assessment of islets of Langerhans encapsulated in alginate.

Improved methods have recently been developed for assessing islet viability and quantity in human islet preparations for transplantation, and these measurements have proven useful for predicting transplantation outcome. The objectives of this study were to adapt these methods for use with microencapsulated islets, to verify that they provide meaningful quantitative measurements, and to test them with two model systems: (1) barium alginate and (2) barium alginate containing a 70% (w/v) perfluorocarbon (PFC) emulsion, which presents challenges to use of these assays and is of interest in its own right as a means for reducing oxygen supply limitations to encapsulated tissue. Mitochondrial function was assessed by oxygen consumption rate measurements, and the analysis of data was modified to account for the increased solubility of oxygen in the PFC-alginate capsules. Capsules were dissolved and tissue recovered for nuclei counting to measure the number of cells. Capsule volume was determined from alginate or PFC content and used to normalize measurements. After low oxygen culture for 2 days, islets in normal alginate lost substantial viable tissue and displayed necrotic cores, whereas most of the original oxygen consumption rate was recovered with PFC alginate, and little necrosis was observed. All nuclei were recovered with normal alginate, but some nuclei from nonrespiring cells were lost with PFC alginate. Biocompatibility tests revealed toxicity at the islet periphery associated with the lipid emulsion used to provide surfactants during the emulsification process. We conclude that these new assay methods can be applied to islets encapsulated in materials as complex as PFC-alginate. Measurements made with these materials revealed that enhancement of oxygen permeability of the encapsulating material with a concentrated PFC emulsion improves survival of encapsulated islets under hypoxic conditions, but reformulation of the PFC emulsion is needed to reduce toxicity.