مجله دانشکده پزشکی اصفهان
پیاپی 259 (هفته اول دی ماه 1392)

Doxorubicin (DOX) is a powerful chemotherapeutic agent used in the treatment of solid tumors and malignant hematological diseases. However, cardiac toxicity limits the clinical usefulness of this drug. Previous reports have shown that corticosteroids induce a cytoprotective effect on cardiomyocytes. Mouse transgenic embryonic stem cell-derived pure cardiomyocytes may be considered as a model for assessment pharmacological and toxicological effects of drugs in vitro. Mouse transgenic embryonic stem cell-derived pure cardiomyocytes were treated by different concentrations of doxorubicin to determine median lethal dose (LD50). Pure cardiomyocytes were evaluated in two groups: treatment by 10 µM dexamethasone (DEX) 24 hours before or before and in continuation with doxorubicin. The percentage of cardiomyocyte viability by MTS assay, the percentage of beating, and quantitative real-time polymerase chain reaction (RT-PCR) for cardiac gene expression (β-MHC) were evaluated in each group. 5 µM doxorubicin was determined as drug concentration that leads to 50% cardiomyocyte mortality. Cardiotoxicity on mouse transgenic embryonic stem cell-derived pure cardiomyocytes could be ameliorated by treatment with dexamethasone (DEX) when administrated before doxorubicin. The effect of dexamethasone appeared to be mediated via glucocorticoid receptors. Dexamethasone increased cardiomyocyte gene expression and decreased apoptosis. Transgenic embryonic stem cell-derived cardiomyocytes are a model for evaluation of doxorubicin toxicity. Additionally, this model provides us with a clinical suggestion, which proposes that the beneficial effect of dexamethasone is obtained when added only before doxorubicin. In addition, the results of present study were consistent with in vivo result in mice.

Hip fracture is one of the most serious problems and the second cause of hospitalization in elderly people. The aim of this study was evaluation of hip fracture in patients with and without diabetes mellitus and its complications. In this cross-sectional study, all patients with hip fracture referred to Yahyanejad and Shahid Beheshti hospitals (Babol, Iran) were enrolled. A checklist including demographic data, site of fracture, type of treatment, duration of hospitalization, complications during and after surgery was filled for each patient. Data were analyzed using t and chi-square tests. From 195 patients, 116 (59.5%) were men and 79 (40.5%) were women. 155 patients (79.4%) were non-diabetic with a mean age of 53.17 ± 25.63 years and 40 (20.5%) were diabetics with a mean age of 67.67 ± 12.25 years. 1 patient (2.5%) had type I and 39 patients (97.5%) had type II diabetes mellitus. In patients without diabetes mellitus, the fracture location was neck of femur in 56.8%, intertrochanter in 21.9%, and head of femur in 18.1%. In patients with diabetes mellitus, 50% was in neck of femur, 35% in intertrochanter and 15% in head of femur. Blood transfusion volume was significantly higher in patients with diabetes mellitus (3.30 ± 1.30 units of packed cell) compared to those without diabetes mellitus (2.43 ± 1.52 units of packed cell) (P = 0.029). According to the high incidence of hip fractures, awareness and care of the patients with diabetes mellitus, especially the elderly, would reduce the incidence of complications.

The application of the ideal binary mask (IBM) for speech signal processing provides remarkable intelligibility improvements in both normal-hearing and hearing-impaired listeners. Binary mask widely applies to the time-frequency (T–F) representation of a noisy signal and eliminates units of a signal below a signal-to-noise-ratio (SNR) threshold while retains others. The factors underlying intelligibility of ideal binary-masked speech were examined and evaluated in the present study. The effects of the local SNR threshold, input SNR level, masker type, and ideal mask-estimator were examined. New estimators including weighted Euclidean and COSH were proposed in which, the human perceptual auditory masking effect and perceptual perception were incorporated. High-performance plateau for SNR thresholds ranging from −20 to 5 dB was observed. Findings could be used for hearing-aid and cochlear-implant designs. Intelligibility of speech was high even at −10 dB SNR for all maskers tested. Performance assessment shows that our proposed estimators can achieve more significant noise estimation as compared to the Wiener estimator.

Thyroid nodules are of the most common thyroid diseases found in about half of adults. Diagnosis of nodules is clinically important because of the risk of cancer. Thyroid gland radionuclide scanning with 99mTcO4 helps the physician to choose better approach to the disease, knowing the activity of the nodule. Neck physical examination before scintigraphy and using a piece of lead marker specifies the location of the nodule in the scintigram to give a more distinct interpretation of the report of the scan. 117 patients with thyroid nodules referred to Seyyed Alshohada Hospital Nuclear Medicine Center (Isfahan, Iran) during 2012-2013 were studied. The patients underwent scanning with 99mTcO4 once; the next time, physical examination of the neck was done and then, scanning was applied; and for the last time, we put a lead marker on the palpated nodule in physical examination, then did the radionuclide scanning. The reports of three scanning tests were compared together. Regarding chi-square test, physical examination of neck and using a lead marker on the palpated thyroid nodule affected the reporting of the scintigram and caused reduction of the false-positive results in both cold and warm nodules (P < 0.05). Also regarding to Wald test, using both mentioned methods resulted in less mistakes in interpretations of the reports of the thyroid scanning. This study showed that, as a simple cost effective method, physical examination of thyroid gland and using lead marker through scintigraphy may be useful in diagnosis of thyroid nodules.

The role of vitamin E as an antioxidant and iron-containing compounds on DNA is not well defined. So, recent study was carried out to determine the role of vitamin E and iron, as both separate and combined effect on sperm protamine deficiency and DNA fragmentation in male rabbits. This study included 42 male rabbits which were randomly divided into seven groups each containing six rabbits.They were all treated under special diets for 6 weeks. After this period the animals were anesthetized and sacrificed. The epididymis duct and vas deferens were dissected and their sperms were extracted from it by Ham's f10 solution. Sperm DNA fragmentation and protamine deficiency were evaluated by the acridine orange and chromomycin A3 staining, respectively. The mean values of protamine deficiency and DNA fragmentation were significantly higher in group that concomitant use of cholesterol and iron. In addition, Vitamin E as an antioxidant agent has a significant effect in reducing these damages. Vitamin E as an antioxidant, decrease sperm DNA damage resulting from the consumption of foods high in cholesterol and iron.