The efficacy of melatonin against radiotoxicity of iodine-131 and its response to treatment in hyperthyroid patients: a randomized controlled trial.

BACKGROUND: Since melatonin is a non-toxic compound with proven radioprotective effects, we aimed to investigate its efficacy in an in-vivo setting in hyperthyroid patients who are treated with iodine-131. This double-blind placebo-controlled study was conducted on hyperthyroid patients referred to nuclear medicine centers in Babol, Iran. We excluded patients suffering from hypertension treated with warfarin, autoimmune diseases, genetic diseases, cancers, smokers, chemical wounded, radiology and radiotherapy workers, and those who were treated with chemotherapy agents. Patients were randomly assigned to receive a capsule containing 300 mg of melatonin powder or a placebo. Just before receiving iodine-131, blood samples were taken from individuals. All 52 female patients received 10 to 20 mCi iodine-131 for treating hyperthyroidism. A second blood sample was taken one hour after the administration of iodine-131. MATERIAL AND METHODS: To determine the chromosomal damages before and after receiving radioiodine, we performed the cytokinesis- block micronucleus assay. Also, at phase 2, 6 months follow-up was performed, in which patients' positive responses to treatment were compared. RESULTS: The findings of this study indicate that the difference in micronucleus formation between the placebo and melatonin groups is not significant. However, a significant difference in the 6 months follow-up revealed that 61.5% and 85.7% of patients had a positive response to treatment in the placebo and melatonin groups, respectively. CONCLUSIONS: As one of the first studies dealing with the human in-vivo assessment on the radioprotective effects of melatonin, it was concluded that melatonin has a non-significant positive impact on reducing the rate of chromosomal damages in hyperthyroid patients treated with iodine-131. Nevertheless, the outcome of treatment was significantly higher by melatonin compared to the placebo group.

Informative combination of CLU rs11136000, serum HDL levels, diabetes, and age as a new piece of puzzle-picture of predictive medicine for cognitive disorders.

Clusterin (CLU) is the third most important associated risk gene in cognitive disorders. Regarding the controversy about the association of CLU rs11136000 with mild cognitive impairment (MCI), the aim of this study was to investigate a putative association of CLU rs11136000 with MCI as well as the serum biological factors with a special attention to the age as a main dimension of a multifactorial elderly disease in an Iranian elderly cohort in which the mentioned association was not previously investigated. The study also checked the association between diabetes and MCI in this population. A population of 418 individuals containing 236 MCI and 192 control subjects was recruited from the Amirkola health and aging population cohort. Serum biological indexes were assessed by biochemical and enzyme-linked immunosorbent assay, and rs11136000 genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism. Bioinformatics analyses were used to identify the putative effect of rs11136000 on the secondary structure of RNA and chromatin location in different cell lines and tissues. Type 2 diabetes was present with a higher proportion in the MCI group in comparison with the control group (P = 0.041). The frequency of the C allele of CLU rs11136000 was significantly different between cases and controls and was associated with MCI risk (OR 1.79, P = 0.019). Under a dominant genetic model, the CC genotype showed a predisposing effect in individuals aged ≥ 75 years (OR 3.33, P = 0.0004). Interestingly, under an over-dominant model, the CT genotype had a protective effect in this population (OR 4.52, P = < 0.0001). We also found a significant association between the genotypes and high-density lipoprotein (HDL) levels in MCI patients (P = 0.0004). Bioinformatics analysis showed that rs11136000 is located in the transcribed region without any regulatory features such as being enhancer or insulator. Also, the T>C transition of CLU rs11136000 could not cause significant mRNA folding (P = 0.950). Contrary to other studies on Asian populations, this study demonstrated an association between rs11136000 and MCI in an elderly Iranian population. This study also suggests that an age-dependent approach to the previous studies may be performed in order to revise the previous belief in this geographical area. The rs11136000 genotypes in combination with HDL levels and knowledge about diabetes background may be used as a predictive medicine tool for cognitive disorders.

Do ejection fraction and other gated stress rest myocardial perfusion parameters differ by age and gender?

BACKGROUND: We have studied the end-diastolic volume (EDV), the end-systolic volume (ESV), and the ejection fraction (EF) for patients who had normal results on treadmill exercise tests and perfusion scans. We also studied normal wall motion as diagnosed by gated myocardial perfusion imaging with the quantitative gated single photon emission tomography (QGSPECT) software set to launch a range of normal values. In addition, we evaluated differences based on age and gender. MATERIALS AND METHODS: All subjects with normal results on Bruce exercise and myocardial perfusion imaging QGSPECT using the 2-days stress-rest technetium-99m (99mTc) sestamibi protocol were enrolled in the study. The quantitated functional data of EDV, ESV, and EF using the QGSPECT software were assessed in the rest and stress studies. The association of quantitated functional data with age and sex at both stress and rest was studied in 78 subjects with no symptoms from the cardiovascular system and normal QGSPECT imaging, 29 males (mean age: 58.41 ± 9.0 years) and 49 females (mean age: 58.18 ± 9.0 years). Also studied were differences between males and females. RESULTS: Our results showed that in women compared with men only stress EF showed a significantly higher value (P = 0.02), whereas all other parameters including REF, SESV, SEDV, RESV, and REDV did not demonstrate a significant difference between men and women (P value > 0.05). CONCLUSION: The study showed that EF as determined by the QGSPECT technique should be considered as gender-matched normative parameter.