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Background & objectives: Cardiac arrhythmia after CABG surgery is a common complication which results in other side effects. Therapeutic effect of prophylactic magnesium administration is controversial and there are many different ideas in this case. The aim of this study was to evaluate the therapeutic effects of magnesium in reducing cardiac arrhythmia after CABG.

Methods: The clinical trial enrolled 140 patients undergoing CABG. Based on the initial blood levels of magnesium, patients were divided into two groups, one group with low serum magnesium and the other group with normal one. The low serum magnesium group treated with magnesium preoperatively and had normal serum magnesium level before operation. Postoperatively, both groups were randomly divided into two sub-groups, one receiving 2 gr. of magnesium sulfate and the other group received placebo. Both groups monitored for occurrence of arrhythmia in the ICU – OH for 3 days. Data were analyzed with statistical methods. P value of <0.05 was considered statistically significant.

Results: The results showed that the occurrence of arrhythmia in any of the sub-groups was not significantly different from each other (p> 0.05). There was no significant relationship between blood levels of magnesium and arrhythmia at different days (p> 0.05).

Conclusions: Blood level of magnesium and prophylactic magnesium administration have not effect on reducing arrhythmia after CABG surgery. The highest incidence of arrhythmias happened in the hypomagnesium group without prophylaxis on the third day after surgery, but this difference was not statistically significant.

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Background & Objectives: Breast cancer is one of the most common cancers of women in the world. Apoptotic pathway is one of the most important pathways to deal with cell damage, especially cancer, which is usually blocked in this disease. One of the main enzymes to set up this pathway is JNK (1,2,3α,3β), which is activated by cellular stress.
Methods: In this study, breast cancer cells with the origin of MCF-7 cell lines were cultured in RPMI medium using 10%fetal bovine serum.Then , they were subjected to heat (42 & 45 ^̊ C) for 1,2,4,6 and 8 hours under X-ray and γ-ray radiations for 1,2,3 and 4 hours as well. Their viability and enzyme level were evaluated by MTT and ELISA tests, respectively.
Results: The obtained results showed that abiotic stresses including heat and radiations resulted in JNK level increase and recovery of apoptosis pathway function in breast cancer cells. In addition, they led to decreased of cell viability and increase of JNK level depending on the duration and kind of stress.
Conclusion: The results in this study showed abiotic stress directly affected the JNK level. Increase of this enzyme in the cell resulted in activity of JNK apoptosis pathway. We hope to find methods to help to cancer treatment by means of more studies on JNK enzyme and relevant pathways.