Relationships between micronutrient losses in sweat and blood pressure among heat-exposed steelworkers.

We aimed to examine the effect of micronutrient losses through sweat on blood pressure (BP) among heat-exposed steelworkers. A total of 224 heat-exposed male steelworkers from an ironworks facility were evaluated in July 2012. We measured the Wet Bulb Globe Temperature Index to evaluate the level of heat stress in the workplace. We collected sweat from the workers during an eight-hour work, and then we measured the micronutrients in the sweat. We also measured the BP of each worker. The results revealed that vitamin C, potassium, and calcium losses in sweat were positively correlated with systolic (SBP) and diastolic (DBP) blood pressure (all P<0.05). A linear stepwise regression analysis revealed that potassium, and calcium losses in sweat adversely affected SBP and DBP (all P<0.05). An analysis of covariance showed that SBP increased when potassium or calcium losses in sweat were >900 mg, or >100 mg, respectively. Further, DBP increased when potassium or calcium losses in sweat were >600 mg or >130 mg, respectively. Therefore, vitamin C, potassium, and calcium losses in sweat may adversely effect BP. To help steelworkers maintain healthy BP, facilities with high temperatures should try to lower environmental temperatures to reduce vitamin C, potassium, and calcium losses in sweat. Additionally, heat-exposed steelworkers may need to increase their dietary intakes of vitamin C, potassium, and calcium. Further research is needed to confirm these findings and support these recommendations.

Mitochondrial membrane potential and reactive oxygen species in cancer stem cells.

Cancer stem cells (CSCs) are believed as the initiators of the occurrence, development and recurrence of malignant tumors. Targeting this unique cell population would provide a less toxic approach than regular chemotherapeutic agents that kill bulk rapid proliferating tumor cells and also normal cells which divide rapidly. To date, major research effort has been aimed at identifying and eradicating CSC population. The metabolism heterogeneity of mitochondria in CSCs shows a big promise for cancer research. Of them, mitochondrial membrane potential (Δψm), reflecting the functional status of the mitochondrion is proved to be highly related to cancer malignancy. Reactive oxygen species, mainly produced from mitochondria, are also increased in many types of cancer cells. However, their statuses in CSCs remain poorly understood. Here we shall review the mitochondrial membrane potential and reactive oxygen species of CSCs and propose the novel potential targets for cancer therapy.

Genetic 135G/C polymorphism of RAD51 gene and risk of cancer: a meta-analysis of 28,956 cases and 28,372 controls.

The RAD51 gene is essential for the repair of damaged DNA related to tumor development. Although a number of genetic studies have attempted to link the 135G/C polymorphism of RAD51 gene to the risk of cancer, the results were inconclusive. The present study aimed at investigating the pooled association using the more comprehensive meta-analysis. The PubMed, EBSCO, and BIOSIS databases were searched to identify eligible studies which were published in English before March 2014. Data were extracted using standardized methods. The association was assessed by odds ratio (OR) with 95 % confidence interval (CI). Begg's test was used to measure publication bias. Sensitivity analyses were also performed to assess the stability of the results. A total of 45 eligible studies with 28,956 patients and 28,372 controls were included in this meta-analysis. Overall, significant association was detected between 135G/C polymorphism and increased cancer risk (C allele vs. G allele: OR 1.23, 95 % CI 1.18-1.28; CC vs. GG: OR 2.41, 95 % CI 2.12-2.74; CC vs. CG: OR 3.86, 95 % CI 3.41-4.37; recessive model: OR 3.57, 95 % CI 3.19-4.00). In further stratified analysis, significantly elevated cancer risk was observed among Caucasians but not Asians. Subgroup analysis by different cancers also showed their significant associations in breast cancer, hematologic malignances, ovarian cancer, colorectal cancer and endometrial cancer, but not in head and neck cancer. Our results indicated that the RAD51 135G/C polymorphism was a candidate for susceptibility of cancer. The effect of the variants on the expression levels and the possible functional role of the variants in different cancers should be addressed in further studies.