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BACKGROUND: Prediabetes is a high-risk state for developing diabetes at an annual rate of 5%-10%. Early intervention can prevent further complications, including metabolic syndrome. Bisphosphonates are commonly used for osteoporotic postmenopausal women. The purpose of this study was to assess the effects of bisphosphonates on lipid profile including triglyceride (TG), total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) of prediabetic postmenopausal women with osteopenia. MATERIALS AND METHODS: In this triple-blind randomized controlled trial, sixty prediabetic, postmenopausal women with sufficient Vitamin D and osteopenia, aged 45-60 years, were randomly enrolled in two groups of intervention (receiving 70-mg alendronate for 12 weeks [duration for maximum metabolic effect of bisphosphonates], n = 30) and control (receiving placebo, n = 30) according to a randomized block procedure of size 2 and 1:1 allocation ratio. The primary outcome of the study, the lipid profile, was evaluated before and after the interventions. The effect of the intervention was assessed using analysis of covariance. RESULTS: The lipid profiles showed no significant differences to the mean values at the baseline in both the groups (all P > 0.05). At the end of the study, the differences between the groups were not significant for 25(OH) D3 (mean difference: -11.09, 95% confidence interval: -32.43-10.25), T (4.19, -30.58-38.97), cholesterol (8.13, -13.07-29.33), LDL-cholesterol (5.07, -10.18-20.31), and HDL-cholesterol (-0.86, -6.04-4.31) when the baseline values and confounders were adjusted (all P > 0.05). CONCLUSION: No statistically significant difference was detected in the serum lipid profile of prediabetic postmenopausal women with osteopenia as a result of alendronate intervention. More studies with larger sample sizes and longer intervention periods are recommended.

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A concern was raised 1 regarding the number of pregnant women in the analysis of reference range for the thyroid hormones in pregnancy 2, where we reported 185 cases and it was believed to be 145 cases.

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The physiological changes during pregnancy modulate the endocrine system. Therefore, both the American and the European thyroid associations recommend the use of local trimester-specific reference intervals. The purpose of this study was to establish the first trimester reference intervals for thyroid function tests in the central area of Iran. We examined 436 pregnant women in their first trimester of pregnancy, and 444 non-pregnant women in a cross sectional study. Serum levels of thyroid stimulating hormone (TSH), free thyroxin (FT4), free triiodothyronine (FT3), thyroid peroxidase antibody, urinary iodine concentration (UIC), and thyroid volume were measured for all subjects. The first trimester-specific reference intervals (2.5th-97.5th percentile) were determined for 185 pregnant women and 256 non-pregnant women with negative TPOAb, adequate iodine level (UIC≥150 µg/l in pregnant and UIC≥100 µg/l in non-pregnant women), and normal thyroid examination. We calculated multiples of the median (MoM) for TFTs to normalize the obtained data. The first trimester-specific reference intervals of serum TSH, FT4, and FT3 for pregnant women were 0.20-4.60 mIU/l, 9.0-18.02 pmol/l, and 3.40-5.64 pmol/l, respectively, while the corresponding figures for non-pregnant women were 0.59-5.60 mIU/l, 9.52-19.30 pmol/l, and 3.70-5.55 pmol/l, respectively. The first and 99th percentile MoM of TSH in pregnant women in their first-trimester was 0.06-4.62. The local normal reference ranges for the first trimester of pregnancy in central region of Iran were different from the ranges suggested by the ATA.

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AIMS: The relationship between obesity and mortality rate among diabetic patients is a controversial topic. The aim of this study was to investigate the association between obesity and all-cause mortality risk in patients with type 2 diabetes. METHODS: In this retrospective database study, 2383 patients with type 2 diabetes, who had been registered in the Isfahan Endocrine and Metabolism Research Center, Iran, were enrolled between 1992 and 2010. The mean (SD) of diabetes duration and follow-up period was 15.5 (8.0) and 7.8 (3.9) years. The main outcome was all-cause mortality. All-cause mortality rates were calculated for the body mass index (BMI) categories of underweight, normal, overweight and class I, II and III obese. Cox proportional hazard models were used to estimate the adjusted hazard ratio for BMI as categorical variable using BMI of 18.5-24.9 kg/m2 as the reference group. RESULTS: The mortality rate in patients with normal weight was higher than overweight patients (59.11 vs. 33.17 per 1000 person-years). The adjusted hazard ratios of all-cause mortality were 0.82 [95%CI 0.68-0.99; P = 0.037], 0.79 [95%CI 0.61-1.02; P = 0.069], 0.71 [95%CI 0.42-1.19; P = 0.191] and 1.36 [95%CI 0.55-3.33; P = 0.507] for overweight, class I, II and III obesity, respectively. When BMI was included in the Cox model as a time-dependent variable, the U-shaped relationship between BMI and all-cause mortality did not change. CONCLUSIONS: The results show a U-shaped association of BMI with all-cause mortality in patients with type 2 diabetes with the lowest risk observed among the overweight patients.

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Lead chalcogenides (PbQ, Q = Te, Se, S) have proved to possess high thermoelectric efficiency for both n-type and p-type compounds. Recent success in tuning of electronic band structure, including manipulating the band gap, multiple bands, or introducing resonant states, has led to a significant improvement in the thermoelectric performance of p-type lead chalcogenides compared to the n-type ones. Here, the n-type quaternary composites of (PbTe)0.75(PbS)0.15(PbSe)0.1 are studied to evaluate the effects of nanostructuring on lattice thermal conductivity, carrier mobility, and effective mass variation. The results are compared with the similar ternary systems of (PbTe)(1-x)(PbSe)x, (PbSe)(1-x)(PbS)x, and (PbS)(1-x)(PbTe)x. The reduction in the lattice thermal conductivity owing to phonon scattering at the defects and interfaces was found to be compensated by reduced carrier mobility. This results in a maximum figure of merit, zT, of ∼1.1 at 800 K similar to the performance of the single phase alloys of PbTe, PbSe, and (PbTe)(1-x)(PbSe)x.

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Recently a significant improvement in the thermoelectric performance of p-type ternary PbTe-PbSe and PbTe-PbS systems has been realized through alternating the electronic band structure and introducing nano-scale precipitates to bulk materials respectively. However, the quaternary system of PbTe-PbSe-PbS has received less attention. In the current work, we have excluded phase complexity by fabricating single phase sodium doped PbTe, alloyed with PbS up to its solubility limit which is extended to larger concentrations than in the ternary system of PbTe-PbS due to the presence of PbSe. We have presented a thermoelectric efficiency of approximately 1.6 which is superior to ternary PbTe-PbSe and PbTe-PbS at similar carrier concentrations and the binary PbTe, PbSe and PbS alloys. The quaternary system shows a larger Seebeck coefficient than the ternary PbTe-PbSe alloy, indicative of a wider band gap, valence band energy offset and heavier carriers effective mass. In addition, the existence of PbS in the alloy further reduces the lattice thermal conductivity originated from phonon scattering on solute atoms with high contrast atomic mass. Single phase quaternary PbTe-PbSe-PbS alloys are promising thermoelectric materials that provide high performance through adjusting the electronic band structure by regulating chemical composition.