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151.

Objectives

The study objective was to assess hydration status by measuring USG among construction workers in Iran.

Materials and Methods

The study design was comparative and experimental. Sixty participants were randomly selected from the construction workers from a construction campus with a similar type of work, climate and diet and formed 2 groups (individuals exposed to the sun and non-exposed individuals). TWL and USG were measured in both groups on 2 consequent days, at the beginning, mid and end of the work shift.

Results

USG test showed that mean USG was 1.0213±0.0054 in the control group and in the exposed group, where it was significantly higher, it amounted to 1.026±0.005. In the exposed group, 38% of workers had a USG level between 1.026–1.030, representing a higher risk of heat illness and impaired performance and 12.72% had a USG level above 1.030 representing a clinically dehydrated status, while this proportion in the control group was 15.2% and 0.58%, respectively. The mean TWL index measure was 215.8±5.2 W/m2 for the control group and 144±9.8 W/m2 for the exposed group, where, again, it was significantly higher. The Pearson correlation measure showed a significant correlation between USG and TWL.

Conclusions

Strong correlation between TWL, as an indicator of thermal stress and USG shows that USG can be considered as a predictor of thermal stress. The difference between USG among the exposed and non-exposed workers and the increase in USG during midday work show the sensitivity of this measure in different thermal and climatic conditions, whereas, the high level of dehydration among workers despite acceptable TWL level, shows that heat stress management without considering the real hydration status of workers, is insufficient.  相似文献   
152.
Knee ligament instability may lead to meniscal and chondral damage, resulting in early osteoarthritis. Due to its superior soft tissue contrast and avoidance of harmful ionizing radiation, MRI has become the most important imaging modality for early recognition of structural defects of the knee joint. This review aims to the understanding of MRI appearances of knee ligament structures associated with knee instability, and to review the common patterns of altered knee mechanics that lead to ligament failure. Normal anatomy of the knee ligaments, pathologic conditions, and postsurgical appearances of the anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament, and posterolateral corner are described. J. Magn. Reson. Imaging 2013;38:757–773 . © 2013 Wiley Periodicals, Inc .  相似文献   
153.
Despite strong evidence of the prevalence of food insecurity in adults and households with children in different areas of Iran, the prevalence of child-specific food insecurity in Iran and especially in Tabriz has not been evaluated. Therefore, the objective of the current study is to evaluate the prevalence of food insecurity in schoolchildren and to identify its social, demographic, and nutritional determinants in Tabriz, Iran. This cross-sectional study was conducted between April and September 2014 among 330 schoolchildren aged 7–11 years comprising 170 boys and 160 girls from ten public schools in Tabriz, Iran. Demographic and socioeconomic factors had been obtained from participants. Food security status was assessed by an eight-item U.S. Department of Agriculture (USDA) Food Security Module previously validated for use in Iran. Dietary information was obtained by a food frequency questionnaire (FFQ). In our findings, the prevalence of food insecurity among children was 30% with 29.1% being low food secure and 0.9% being very low food secure. Mean weight for age Z-score (WAZ) in the food insecure group was significantly lower than in the food secure group. The prevalence of food insecurity was more prevalent in boys (p = .006). Food insecure children had a significantly lower intake of energy, carbohydrate, protein, and meat (p < .001) and higher prevalence of wasting compared with their counterparts in the food secure group (p = .004). These results suggest a proportionally high prevalence of food insecurity in schoolchildren in Tabriz and its significant association with poor nutritional status and dietary habits. Our findings also ensures the necessity of nutritional support programs and nutritional education in Iranian low-income families to improve their overall health.  相似文献   
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Motor cortex injuries in adulthood lead to poor performance in behavioral tasks sensitive to limb movements in the rat. We have shown previously that motor cortex injury on day 10 or day 55 allow significant spontaneous recovery but not injury in early adolescence (postnatal day 35 “P35”). Previous studies have indicated that injection of basic fibroblast growth factor (FGF-2) enhances behavioral recovery after neonatal cortical injury but such effect has not been studied following motor cortex lesions in early adolescence. The present study undertook to investigate the possibility of such behavioral recovery. Rats with unilateral motor cortex lesions were assigned to two groups in which they received FGF-2 or bovine serum albumin (BSA) and were tested in a number of behavioral tests (postural asymmetry, skilled reaching, sunflower seed manipulation, forepaw inhibition in swimming). Golgi-Cox analysis was used to examine the dendritic structure of pyramidal cells in the animals’ parietal (layer III) and forelimb (layer V) area of the cortex. The results indicated that rats injected with FGF-2 (but not BSA) showed significant behavioral recovery that was associated with increased dendritic length and spine density. The present study suggests a role for FGF-2 in the recovery of function following injury during early adolescence.  相似文献   
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160.

Purpose

Breast cancer is a significant health problem worldwide, accounting for a quarter of all cancer diagnoses in women. Current strategies for breast cancer treatment are not fully effective, and there is substantial interest in the identification of novel anticancer agents especially from natural products including toxins. Cytotoxins are polypeptides found in the venom of cobras and have various physiological effects. In the present study, the anticancer potential of cytotoxin-II against the human breast adenocarcinoma cell line (MCF-7) was investigated.

Methods

The cytotoxic effects of cytotoxin-II were determined by morphological analysis and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The mode and mechanism of cell death were investigated via acridine orange/ethidium bromide (AO/EtBr) double staining, flow cytometric analysis of cell death, detection of mitochondrial membrane potential, measurement of intracellular reactive oxygen species (ROS), annexin V/propidium iodide staining, and caspase-9 activity assays.

Results

The half maximal inhibitory concentration (IC50) of cytotoxin-II in MCF-7 cells was 4.18±1.23 µg/mL, while the value for cisplatin was approximately 28.02±1.87 µg/mL. Morphological analysis and AO/EtBr double staining showed typical manifestations of apoptotic cell death (in doses lower than 8 µg/mL). Dose- and time-dependent ROS generation, loss of mitochondrial membrane potential, caspase-9 activation, and cell cycle arrest were observed in their respective tests.

Conclusion

In conclusion, cytotoxin-II has potent anticancer effects in the MCF-7 cell line, which are induced via the intrinsic pathways of apoptosis. Based on these findings, cytotoxin-II is a suitable choice for breast cancer treatment.  相似文献   
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