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Exposure to cigarette smoke is emerging as an environmental risk factor for multiple sclerosis (MS). We investigated the possible association between environmental tobacco smoke, its cumulative exposure, and MS risk. We used data from the Iranian Multiple Sclerosis Registry to identify a case-control of 662 patients who had MS and a comparison group of 394 patients. Information regarding current smoking status, including the number of cigarettes smoked per day, duration, and smoking pack-years indicative of cumulative dose of tobacco smoked was obtained. We analyzed the incidence of MS among ever–smokers who had been smokers during their disease course and prior to disease onset in comparison with never–smokers who had never been exposed by calculating the odds ratio (OR) with a 95% confidence interval (CI) employing logistic regression. Of the 662 MS patients, there were 523 women (79.0%) and 139 men (21.0%), with a mean age of 31 ± 10.0 years at disease onset. The risk for MS was increased among ever–smokers (OR = 1.78, 95% CI = 1.22–2.59, p = 0.03) compared to never–smokers. As compared with never smokers, the OR for patients with 6–10 pack years was 2.91 for men (95% CI = 1.11–9.47, p = 0.03) and 1.69 for women (95% CI = 1.02–6.45, p = 0.04). Our results demonstrate that cigarette smoking is significantly associated with an increased risk for MS. The risk effects of smoking were more noticeable in male patients and at higher tobacco doses.  相似文献   
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Manganese inhibits oxidative stress damage. The aim of this study was to investigate the protective role of manganese on testis structure and sperm parameters in adult mice exposed to formaldehyde (FA). Twenty adult male NMRI mice were selected and randomly divided into four groups: (i) control; (ii) sham; (iii) ‘FA’‐exposed group; and (iv) ‘FA and manganese chloride’‐exposed group. The FA‐exposed groups received 10 mg kg?1 FA daily for 14 days, and manganese chloride was just injected intraperitoneally 5 mg kg?1 on 2nd weeks. Mice were sacrificed, and spermatozoa were collected from the cauda of the right epididymis and analysed for count, motility, morphology and viability. The other testicular tissues were weighed and prepared for histological examination upon removal. Seminiferous tubules, lumen diameters and epithelium thickness were also measured. The findings revealed that FA significantly reduced the testicular weight, sperm count, motility, viability and normal morphology compared with control group (P ≤ 0.05). In addition, seminiferous tubules atrophied and seminiferous epithelial cells disintegrated in the FA group in comparison with the control group (P ≤ 0.05). However, manganese improved the testicular structure and sperm parameters in FA‐treated mice testes (P ≤ 0.05). According to the results, manganese may improve and protect mice epididymal sperm parameters and testis structure treated with FA respectively.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Despite advances in therapeutic strategies in the management of cancer, malignant glioma remains difficult to...  相似文献   
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Aims

Some studies have demonstrated that metabolic syndrome is associated with hematological parameters. The present study explores the relationship between hematological parameters and numbers of metabolic syndrome conditions in Iranian men.

Methods

This cross-sectional study included 11,114 participants who were professional drivers of commercial motor vehicles, and were enrolled in the Iranian Health Surveys between 2014 and 2016. Diagnosis of metabolic syndrome was made according to International Diabetes Federation criteria. Clinical data, including anthropometric measurements and serum parameters, were collected. Odds ratios for hematological parameters and metabolic syndrome were calculated using binary logistic regression models.

Results

We found that hemoglobin; platelet, and white blood cell counts increased with increasing numbers of metabolic syndrome components (p < 0.05 for all). The odds ratio of metabolic syndrome significantly increased across successive quartiles of platelet (1.00, 1.25, 1.29, and 1.51) and white blood cell counts (1.00, 1.51, 1.79, and 2.11) with the lowest quartile as the referent group. Similar associations for hemoglobin and hematocrit in the top quartile were also observed. We did not observe any significant difference in the mean of neutrophil count, mean platelet volume (MPV), red cell distribution width, or platelet distribution width among participants with or without metabolic syndrome.

Conclusions

Our findings indicate that high levels of major hematological parameters such as hemoglobin, hematocrit, as well as platelet and white blood cell counts could be novel indicators for the development of metabolic syndrome.  相似文献   
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Little is known of the natural history of thymic carcinoids in multiple endocrine neoplasia type 1 (MEN1). This is important because in 1993 they were identified as a frequent cause of death, yet only small retrospective studies and case reports exist. We report results of a prospective study of 85 patients with MEN1 evaluated for pancreatic endocrine tumors and followed over a mean of 8 yr with serial chest computed tomography, magnetic resonance imaging (MRI), chest x-ray, and, since 1994, octreoscans [somatostatin receptor scintigraphy (SRS)]. Seven patients (8%) developed thymic carcinoids. Patients with and without carcinoids did not differ in clinical, laboratory, or MEN1 tumor features, except for male gender and the presence of a gastric carcinoid. All thymic tumors were hormonally inactive. Four thymic carcinoids lacked 11q loss of heterozygosity, although it was found in three pancreatic endocrine tumors. Computed tomography and/or MRI were more sensitive than SRS or chest x-ray in detecting tumors initially or with recurrence. All patients underwent resection of the thymic carcinoid, and in all patients followed more than 1 yr, the tumor recurred. Bone metastases developed in two patients and were detected early only on MRI, not SRS. This study provides information on early thymic carcinoids and allows modifications of existing guidelines to be recommended for their diagnosis, surveillance, and treatment.  相似文献   
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