Acute hyperhomocysteinemia impairs endothelium function in subjects with type 2 diabetes mellitus.

The objective of the present study was to examine the effect of acute, methionine-induced hyperhomocysteinemia (HHCY) on endothelial function and indices of arterial stiffness in subjects with type 2 diabetes mellitus (T2DM). A total of 30 subjects with T2DM, free of macrovascular disease were examined in a crossover study. L-methionine (M) (0.1 g/kg) and water (W) load were given in random order with an interval of about 1 week in between. Endothelial function was assessed by flow-mediated vasodilation (FMD). Arterial stiffness was assessed by determination of augmentation index (AI). Measurements were performed in the fasting state, 1, 2 and 3 h after the M or the W load. Total plasma homocysteine (HCY) levels did not change after W administration, while M administration resulted in a significant increase in HCY concentrations at 3 h. FMD throughout the experiment expressed as area under the curve (AUC) was significantly lower after the M than after the W load. Consistent with impairment in endothelial function, the AUC of AI was significantly higher after the M than after the W administration. Acute HHCY impairs endothelial function and increases arterial stiffness in patients with T2DM. This effect is probably mediated by a reduction of nitric oxide bioavailability in endothelium.

Differential effects of high-fat and high-carbohydrate content isoenergetic meals on plasma active ghrelin concentrations in lean and obese women.

AIM: To study the effect of two different isoenergetic meals, one rich in carbohydrates and one rich in fat, on plasma active ghrelin levels in lean or obese subjects. METHODS: Eight obese and eight lean women, strictly matched for age, were fed two isoenergetic meals of different composition, one rich in fat and one rich in carbohydrates (CHO), on separate days. Plasma active ghrelin levels were measured just before and at 1, 2 and 3 hours after meal consumption. RESULTS: Overall, plasma active ghrelin levels were significantly lower in the obese compared to the lean women (71.7 +/- 29.7 vs. 222.2 +/- 127.2 pmol/liter respectively, p < 0.0001). Furthermore, ghrelin levels decreased significantly by 30 % from baseline values in the lean subjects in the first hour after the CHO-rich meal (mean difference +/- SD): -66.2 +/- 49.0 pmol/liter (p = 0.03), returning to near-baseline levels by 2 hours, while no significant change was observed in the obese subjects. After the fat-rich meal, active ghrelin levels did not change significantly in either group (p > 0.05). CONCLUSIONS: A fat-rich meal does not suppress plasma active ghrelin levels in either lean or obese women. Moreover, in obese, unlike lean women, a high carbohydrate meal also fails to suppress plasma ghrelin levels, which are already quite low. This suggests that ghrelin-induced satiety mechanisms may be compromised in these subjects.

Acute respiratory distress syndrome due to miliary tuberculosis in a patient with rheumatoid arthritis under corticosteroid therapy.

We report the case of a 65-year-old woman with rheumatoid arthritis (RA) under corticosteroid therapy who presented with high fever and dyspnea and who, within 48 h, developed acute respiratory distress syndrome (ARDS) due to Mycobacterium tuberculosis (MTB). Miliary tuberculosis is a rare cause of ARDS; however, because of its ominous outcome, it should be included in the differential diagnosis of immunocompromised patients with rapidly worsening respiratory discomfort. A brief review of miliary tuberculosis as a cause of ARDS is presented.