پژوهش در علوم پزشکی
سال:1384 | دوره:10 | شماره:4 |تعداد مقالات:20

BACKGROUND: Patients with Alzheimer's disease (AD) reportedly exhibit hypersensitivity to much diluted tropicamide solution (0.005%), a M4 muscarinic receptor antagonist. Therefore intraocular application of 0.005% tropicamide may be useful for screening dementia. The aim of this study was to simplify the pupil response test by using a new image analyzing system, which consists of a cheap, simple, and easy to use web-camera and a computer.METHODS: Intraocular tropicamide of 0.005% concentration was administered in 3 groups: Alzheimer's disease patients (n=8, average age=76±5), non-Alzheimer's disease elderly (n=6, average age=65±7), and young subjects (n=8, average age=28±5). Every 5 minutes for 60 minutes, image of the eye's shape were taken, and the diameter of the pupils was measured.RESULTS: The results showed that differences in pupil dilation rate between Alzheimer's disease and non-Alzheimer's disease subjects were statistically significant. ROC analysis showed that after 35 minutes the sensitivity and specificity of the test were 100%.CONCLUSIONS: Based on our results, we concluded that this recording system might be an appropriate and reliable tool for pupil response diagnosis test of Alzheimer's disease.

BACKGROUND: Trans-fatty acids (TFAs), unsaturated fats with at least one double bond in the Trans configuration, are industrially formed in large quantities when vegetable oils are partially hydrogenated. This study was undertaken to quantify the amounts of the common fatty acids in several commercial oils marketing in Iran.METHODS: The most consumed commercially available brands of vegetable oils were randomly selected from products available in supermarkets. A 10g sample was drawn from each mixed sample and prepared for fatty acid analysis by gas chromatography (GC).RESULTS: Palmitic acid (C16:0) and stearic acid (C18:0) jointly constituted 21% of total fatty acids in partially hydrogenated vegetable oils (PHVOs). More than one third of total fatty acids in Iranian PHVOs were Trans fats. TFAs constituted almost 1% and 3% of total fatty acids in Iranian cooking and frying oils. This study showed higher contents of TFAs in Iranian commercially available hydrogenated vegetable oils. Statistical Package for Social Sciences was used for all statistical analyses.CONCLUSIONS: Although several studies reported multiple adverse effects of TFAs on human health, limited information is available about total fatty acid composition, particularly TFAs, in Iranian edible oils. Our findings indicated higher content of TFAs in Iranian commercially available PHVOs.

BACKGROUND: A single nucleotide variation within catechol-o-methyl transferase (COMT) gene may alter the COMT enzyme activity level. Polymorphism of Val158Met in the COMT gene has been related to malignancy. In this regard, a study was carried out to find a possible association between the COMT gene polymorphism in patients with sporadic prostate cancer (PCa) and benign prostatic hyperplasia (BPH).METHODS: All types of COMT158 Val/Met polymorphism were carried out using ASO-PCR method in 41 patients with prostate cancer, 193 patients with benign prostatic hyperplasia and 107 healthy male individuals.RESULTS: The results of this study showed that the frequency of low producer allele A at codon 158 of the COMT gene is significantly different in BPH group compared to normal male control group (OR, 95% CI, p value 1.95: 1.46, 2.44, 0.021, respectively). However no significant difference was noticed when the comparison was made between prostate cancer group and normal male control group and also between BPH and PCa groups.CONCLUSIONS: Decreased level of catechol-o-methyl transferase gene activity may play a possible role in benign prostatic hyperplasia development but not in prostate cancer. Increased level of COMT gene activity has a protective role against BPH.

BACKGROUND: The aim of this study is to assess the effect of pre-pregnancy physical training on metabolic responses and its effects on offspring.METHODS: Three groups of rats (n=7 in each group): sedentary pregnant rats (PS), exercised during pregnancy (PE) and pregnant rats trained before and during pregnancy (PT) were compared. They were separated into three subgroups regarding water temperature: 28oC, 35oC or 39oC. Plasma triglycerides and glucose levels, weight gain during pregnancy and rectal temperature pre and post exercise (swim), as well as the offspring size and weight were analysed.RESULTS: Rectal temperature post exercise was lower than pre exercise at 28oC and 35oC, and higher at 39oC. Weight gain was lower at 39oC for the PT group and at 35oC for the PT and PE groups compared to the PS group. Plasma glucose, at 28oC and 39oC for PS and PE groups, was higher than those obtained at 35oC, while triglycerides were lower. For trained rats, plasma glucose and triglycerides were similar at all water temperatures. Trained rats presented lower triglyceride values at 35oC, and higher triglyceride values at 39oC compared to PS group. Glucose presented inverse results. None of the groups presented fetal reabsorption. However, in the PS group, the offspring presented lower weight gain at 28oC than at 35oC and 39oC.CONCLUSIONS: These results suggest that pre-pregnancy physical training induces steady values of triglycerides and glucose during exercise at all water temperatures.

BACKGROUND: Electromagnetic fields are associated with production, transmission and use of electricity. In this study we have investigated the effects of short and long time alternative magnetic fields' (AMF, 50 Hz) exposure on the secretion of hypothalamic-pituitary-gonadal axis in the male rats.METHODS: Forty eight Wistar male rats, same range of age and weight were divided into four groups and each group contained 12 rats. After one-week adaptation each group were exposed to AMF (0, 25, 50 and 100 4T respectively) for 17 days, 5 hours a day. In the second protocol the time of exposure extended to 34 days. After experiments rats' blood serums were removed from their blood samples and kept frozen for usage. The results were analyzed by one way- ANOVA statistical method (p<0.05).RESULTS: Chronic exposures (5h/day for 34 days) to AMFs had no effect on serum's testosterone and LH. But, AMF at 100 4T induced an increase of serum's FSH level in comparison with 25 mT, 50 4T and control groups. In contrast, subchronic AMFs (5 h/day for 17 days) induced a decrease of serum's testosterone in control group in comparison with 25, 50 and 100 4T groups. But these AMFs had no effect on serum's LH and FSH levels.CONCLUSIONS: Increased level of FSH suggests damage to the seminiferous tubules. Our results suggest that AMFs probably causes dysfunction in gonadal axis at the hypothalamic-pituitary level in male rats in different protocols.

BACKGROUND: E-cadherin/catenin complexes exert a role in cell adhesion. b-catenin is a key player in Wnt signaling pathway in gastric cancer. P53 is a tumor suppressor gene which also regulates apoptosis. We assessed the expression of E-cadherin, b-catenin and p53 in gastric adenocarcinoma, and their correlations with clinicopathological features.METHODS: Fifty six formalin-fixed, paraffin-embedded archival specimens of gastric adenocarcinoma were randomly included as cases. Adjacent tumor-free gastric mucosa of different premalignant stages was obtained from the cases.Immunohistochemical staining was performed to assess E-cadherin, b-catenin and p53 expression.RESULTS: All chronic atrophic gastritis and intestinal metaplasia revealed normal membranous staining. Only one patient with dysplasia had abnormal expression of E-cadherin and b-Catenin. Abnormal E-cadherin, b-catenin and p53 expression was found in 50%, 48.2% and 76.8% of cancer specimens respectively. Abnormal expression of E-cadherin was significantly correlated with aberrant b-catenin expression. Abnormal E-cadherin and b-catenin expression were significantly correlated with depth of tumor invasion and advanced gastric cancer (p<0.05), lower degree of differentiation and diffused tumor type (p<0.001). Node metastasis was not influenced by abnormal expression of E-cadherin and b-catenin. P53 was not associated with clinicopathological variables.CONCLUSIONS: Abnormal expression of the E-cadherin and b-catenin were associated with each other and influenced by histogenesis of gastric cancer and malignant behavior of tumor but not significant in premalignant lesions. They are more frequent in diffuse type and associated with advanced gastric cancer. P53 alterations are more frequent in the Iranian population compared with others.

Hepatitis B virus infection is a major public health problem worldwide. Islamic Republic of Iran is a country in which hepatitis B prevalence is intermediate. The aim of this study is to assess prevalence of chronic hepatitis B infection in Iran according to demographic characteristics. All cross-sectional studies concerning prevalence of chronic hepatitis B infection in Iran were included irrespective of date and language. The outcome of interest was prevalence of chronic hepatitis B infection confirmed by blood specimen positive for HBsAg. The prevalence of chronic hepatitis B infection was estimated about 1.7% or lower in general population; 0.8% (95% CI: 0.6% to 0.9%) in blood donors and 3.2% (95% CI: 2.3% to 4.1%) in intravenous drug users and varied from zero to 1.5% in beta thalassemic patients. Since mass vaccination in 1993, prevalence of chronic hepatitis B infection has being reduced among children and adolescents. This reduction can be attributed to the effectiveness of the national immunization program and it may impact on reduction of prevalence of hepatitis B infection in general population.

Avulsion of the globe is a rare event, and there are only a few reports of true total enucleation of the globes in the literature. We report a 20-year-old man who was a victim of car accident, with bilateral enucleation of the globe. This is the third reported case of bilateral subluxated globes that were successfully repositioned in the orbits. Although the patient had no light perception vision, preserving his one eye reduced the psychological stress of sudden traumatic loss of vision for him and his relatives.

The most common gastrointestinal involvement in neurofibromatosis is due to tumoral lesions which may present with gastrointestinal bleeding or obstruction. We report a case of concurrent ulcerative colitis and neurofibromatosis. A 39 year-old woman, known case of neurofibromatosis, was admitted to our department with complaint of chronic bloody diarrhea. After thorough clinical examination and paraclinical assessments, including colonoscopy and biopsy, ulcerative colitis was confirmed as the cause of gastrointestinal bleeding. Another rare finding in this patient was bilateral neurofibroma in psoas muscle that was detected on abdominal spiral Computer Tomography scan.