t. neyestani

The main objective of this study was to investigate the effects of magnesium, zinc, vitamins C and E, and a combination of these micronutrients with vitamin B groups (B1, B2, B6, B12, folic acid and biotin) on blood pressure in type 2 diabetic patients. In a randomized, double-blind, placebo controlled clinical trial, 67 type 2 diabetic patients, 36-69 years old, stratified for sex and were randomly divided into three groups. Each subject received two capsules per day for a period of 4 months, each capsule containing one of the following preparations: Group 1 received 250 mg magnesium and 20 mg zinc, 200 mg vitamin C and 100 mg vitamin E, 10 mg vitamin B1, 10 mg vitamin B2, 10 mg vitamin B6, 10 μg vitamin B12 and 1 mg folic acid (n=22). Group 2: 250 mg magnesium and 20 mg zinc, 200 mg vitamin C and 100 mg vitamin E, (n=23), and group P: placebo (n=22). Blood pressure and biochemical analysis were determined at the beginning and after 2 and 4 months. Fasting blood glucose and HbA1c were determined by glucose oxidase and chromatography methods, respectively. Plasma vitamin C and serum magnesium and zinc were determined by the colorimetric method and serum α-tocopherol using HPLC. Serum malondialdehyde (MDA) was determined by a colorimetric method. Treatment effects were analyzed by general linear modelling. Results indicate that after 2 and 4 months of supplementation levels of plasma vitamin C increased in group 1 (p<0.0001) and group 2 (p=0.029 and p<0.0001, respectively). Serum vitamin E increased in group 1 and 2 (p<0.0001) and serum folic acid increased in group 1, after 2 and 4 months supplementation (p<0.0001). Serum magnesium increased in group 1 after 2 months supplementation (p=0.001) but not after 4 months. After 2 or 4 months supplementation, there were no significant changes in fasting blood glucose or HbA1c in the 3 intervention groups. Levels of systolic blood pressure decreased significantly in group 2 after 4 months supplementation (p=0.012). After 2 and 4 months supplementation, diastolic blood pressure decreased significantly in group 1 (p=0.003 and p=0.012, respectively) and in group 2 (p<0.0001 and p=0.002, respectively) and mean arterial blood pressure decreased in group 1 (p=0.018 and p=0.025, respectively) and in group 2 (p=0.002). Also serum malondialdehyde decreased significantly in groups 1 and 2 (p=0.009 and p=0.041, respectively) after 4 months. The results of the present study indicate that in type 2 diabetic patients, combination of vitamins and minerals might decrease blood pressure.

Lipid abnormalities, especially high serum Lp(a) concentration, is one of the major causes of cardiovascular diseases in peritoneal dialysis patients. The present study was designed to investigate the effects of soy consumption on serum lipid and apoprotein levels in peritoneal dialysis patients.

The study was a randomized clinical trial in which 40 peritoneal dialysis patients (20 males and 20 females) were randomly assigned to either a soy or a control diet. The patients in the soy group received 28 g/d textured soy flour (containing 14 g soy protein) for 12 weeks, while the patients in the control group consumed their usual diet without any soy. At the baseline and at the end of the period, from each patient 5 ml blood were collected after a 12- to 14-hour fast and serum triglyceride, total cholesterol, HDL-C, LDL-C, apoAI, apoB100, Lp(a), TNF-α, albumin, and phosphorus measured.

The serum Lp(a) concentration in more than 86% of the peritoneal dialysis patients was above the normal range. As compared to the baseline value, the mean serum Lp(a) concentration decreased significantly by 41% (P<0.01) in the soy group at the end of 8-week period, and the reduction was significant as compared to the control group (P<0.05). The mean serum Lp(a) concentration did not change significantly in the control group. There were no significant differences between the 2 groups with regard to mean changes in the serum triglyceride, total cholesterol, HDL-C, LDL-C, apoB100, apoAI, TNF-α, albumin or phosphorus levels.

The results of the present study indicate that soy consumption reduces serum Lp(a) concentration considerably in peritoneal dialysis patients. Therefore, it may be effective in preventing cardiovascular diseases in these patients.

Although there are reports in the literature on the antimicrobial effects of green tea, the effect of black tea, the most common beverage in Iran, on growth of bacteria, such as Streptococcus pyogenes, has not been studied extensively. This study was undertaken to determine the inhibitory effect of black tea on the growth of Streptococcus pyogenes in vitro and compare it with green tea.

Extracts from both green and black teas were prepared using the percolation method and dried. This was followed by assessment of the total anti-oxidant capacity (TAOC) of solutions of the dried extracts with different concentrations. The assessment was done by determining percentage inhibition of oxidation of ABTS and reduction of its radical by 1 mg/ml extracts of black and green teas at 37°C. Viability of the bacteria was determined by exposing them to different concentrations of the tea extracts in an aqueous medium and then transferring the cultures to a solid medium, followed by colony counting at certain intervals. In the next step, the growth inhibitory effects of black and green tea extracts were determined on the basis of interactions between the extracts with some of the antibiotics routinely used against Gram-positive by the disc diffusion method (11 times on different days).The data were analyzed using the Wilcoxon sign and Kruskal Walis tests.

The data showed that the antioxidant capacity of green tea extract is significantly higher than that of black tea extract (p<0.001). Conjugation of the standard antibiotics disk with 1.25 mg green tea extract had a synergistic effect on ampicilin in a dose-dependent manner, it had no effect on amoxicillin, but an inhibitory effect on cephalexin. Increasing the green tea extract dose to 2.5 mg caused the zone of inhibitory growth of cephalexin to return to the basal limit and that of amoxicillin even beyond that. In the case of black tea, the increased doses resulted in increases in the antibacterial effect of ampicilin in vitro, reaching statistical significance (P<0.001) at the 2.5mg dose. Although a 1.25 mg-dose of black tea extract inhibited the antibacterial effect of amoxicilin and cephalexin, the inhibitory effect decreased significantly (p<0.001) when the dose was increased to 2.5 mg; however, the zone of inhibition was still less than the basal limit.

It seems that the inhibitory effects of tea on bacterial growth is directly related to its TAOC. The mechanism involved is probably through production of hydrogen peroxide by the tea polyphenols acting as pro-oxidants. Our findings indicate the possibility of using proper amounts of tea or polyphenols as nutritional supplements as an adjunct nutritiona therapy in certain infections.