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 Background & Objectives: Clinical findings show that stress can gradually affect the activity of various systems of the body such as immune system and impair them. Different variables potentiate and modify this effect. This research aimed at studying the relationship of personality traits (self-respect, tenacity, type A personality), stress, and stress coping skills with immune system status in nurses.

 Methods: In this descriptive-analytical study, 246 individuals were selected by simple random sampling method. At the first stage, the subjects on the job completed the questionnaires of self-respect, tenacity, type A personality, stress, and stress coping skills. At the second stage to determine the amount of antibodies, 2-cc blood of the subjects was assessed. The data were analyzed using correlational methods.

  Results: The findings indicated a significant, positive and meaningful relationship of immunoglobulin antibody with “self-respect”, and IgM antibody with “type A personality” in male nurses (p<0.05). But there was no significant relationship between the immune system variables and tenacity, stress, and stress coping skills. From among the predictive variables (self-respect, tenacity, type A personality, stress, and stress coping skills) only the stress variable had significant relationship with the criterion variable (IgA antibody)(p=0.05).

 Conclusion: Regarding the results it can be said that self-respect may adjust IgG variable in stress positions (especially in chronic stress). So in hard jobs such as nursing, psychological characteristics should be considered as an important job factor along with physical capabilities.

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Leishmaniasis is a tropical parasitic disease that has become a major health challenge in many countries of the world. Not only has not been found any effective vaccine or treatment for the disease eradication, but also the advent of drug resistance is also increasing. Therefore, it is vital to take a precise attention to the physiochemical cycles of the Leishmania parasite and to identify its biochemical pathways. One of the most important biochemical pathways of host and parasite is the arginase and nitric oxide cycles. By using L-arginine, arginase plays an important role in the metabolic pathways, particularly in ornithine production, polyamines biosynthesis and cellular activities, including proliferation and cell survival. Furthermore, L-arginine, can act as a substrate for inducible nitric oxide synthase (iNOS), which leads to the synthesis of nitric oxide (NO), thereby activating the cellular immune system and clearing intracellular parasites. High Arginase activity reduces the parasite load inside the host cell, and since lymphocytes need L-arginine for their activity, its deficiency impairs the response of host immune cells. Also, parasites arginase alone can determine the fate of Leishmania parasite within the host cell. The aim of this study was to provide a comprehensive overview of various studies on the arginase activity of both parasite and host and its direct impacts on the immune system and pathogenicity of the Leishmania parasite.
 

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Background & objectives: Caffeine can affect many physiological functions of the body. The aim of this study was to investigate the response of aerobic function, blood pressure and some immune system factors of trained men to acute caffeine consumption in dehydrated condition and warm and humid environment.
Methods: Thirty male athletes with a mean age of 26.6±3.9 years in dehydrated conditions voluntarily participated in this study, which was performed in a double-blind manner. Subjects were divided into three groups: caffeine consumption group (n=10), placebo group (n=10) and control group (n=10). The Caffeine group consumed 6 mg/kg body weight of caffeine. Sixty minutes later, the subjects performed an increasingly exhausting exercise. Blood samples collecting and blood pressure measuring took place before, immediately after and 24 hours after exercise. Analysis of variance with repeated measures (group * time) and one-way analysis of variance were used for statistical calculations.
Results: The duration of the exhaustion test in the caffeine consumption group was significantly longer than the control (p≤0.01) and placebo (p≤0.05) groups. In the blood sampling immediately after exercise, the level of leukocytes, neutrophils and lymphocytes in the exercise groups were significantly higher than the control group (p≤0.001). Also, the caffeine group experienced a lower increase in leukocytes and neutrophils compared to the placebo group (p≤0.001). Blood pressure values ​​in the exercise groups were significantly higher than the control group (p≤0.001). Also, the caffeine group experienced a greater increase in systolic blood pressure at baseline and immediately after exercise compared to the placebo group (p≤0.001).
Conclusion: In general, exhausting exercise in a warm environment and dehydrated condition increases the number of immune system cells and blood pressure. In addition to improving aerobic function, caffeine seems to prevent further increases in the number of immune system cells, while increasing blood pressure in the normal range in warm and humid environment.