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Background and Objective: Golestan province in north of Iran is known as a high risk area for cancers. Differences in climatic characteristics including rainfall, temperature and humidity may affect the diet, types of vegetation and lifestyle of residents in this area. The aim of this study was to determine the relationship between rainfall and temperature with the incidence of cancer in Golestan province, north of Iran.
Methods: In this descriptive-analytic study, climatological data and Data of cancer incidence in Golestan province, north of Iran were collected during 2005 and 2010.
Results: Higher incidence of cancers was seen in areas with dried climate including Eastern parts of the province and the Turkmen sahra (P<0.05). A significant negative correlation was found between the rainfall and the incidence of esophageal cancer (r=-0.64, P<0.04). The average rainfall was significantly lower in high-risk area for esophageal cancer than in low-risk area (P<0.05). The incidence of gastric cancers was significantly higher in dry climate than humid climates (P<0.05). The incidence of esophageal and intestinal cancers was non-significantly higher in dry climate than humid climates. The incidence of breast cancer was non-significantly lower in dry climate than humid climates.
Conclusion: This study showed that higher incidence of cancers in dry climates when compared with humid climates. Also, environmental factors may play a role in high incidence rate of cancers in this area.

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Background and Objective: Listeria monocytogenes is a gram-positive and foodborne pathogen that is psychrophilic and has the ability to tolerate a high percentage of salt by more than 10%. This bacterium grows in many food products that have a long shelf life. This study was performed to evaluate the expression of genes hly and inlA of Listeria monocytogenes bacteria in the viable but non-culturable (VBNC) condition in temperatures of 4 degrees Celsius.
Methods: In this descriptive laboratory study, bacteria in 10⁶ counts in mid log phase were inoculated into BHI Agar rich medium and It was investigated and stored at refrigerated temperature (4 degrees Celsius) until the cultivate was lost. At the end of the 16S rRNA gene, the hly and inlA genes were studied as pathogenic genes of this bacterium. The expression of these genes before and after entering to VBNC state was performed to compare their expression.
Results: Listeria bacteria lost its cultivation ability after 5 months of storage at a refrigerated temperature. The results of the gene expression analysis showed that at the end of the period, the bacterium entered "Viable But non-Culturable" form; also the hly and inlA pathogenic genes were not expressed in riched medium. By adding blood to the rich culture medium of this bacterium, the hemolysin O pathogen gene was re-illuminated.
Conclusion: The results of this study show that the possibility of bacterial entry into VBNC mode occurs at the refrigerator condition, and the expression of its pathogenic genes is affected. Blood and its agents can act as an agent for the induction and clarification of the hly gene. Therefore, it is necessary to review the microbial quality control of fishery products.

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Background and Objective: Stroke has a high prevalence and is associated with a high premature mortality rate. Thus, it is important to identify the effective factors in increasing the incidence of stroke. The aim of this study was to investigate the role of seasonal changes and environmental factors in the occurrence of stroke.
Methods: This descriptive-analytical study was done on 3,639 patients including 3,102 (85.3%) with ischemic stroke, 472 (12.9%) with intracerebral hemorrhage and 65 (1.9%) with subarachnoid hemorrhage patients. After measuring environmental factors such as air temperature, air pressure, humidity and geomagnetic field, admission data of stroke patients between 2015-2019 were extracted from the Sayyad Shirazi Hospital information system.
Results: The mean occurrence of intracerebral hemorrhage was highest in winter, especially in January and March, and lowest in summer, especially in July and August. Intracerebral hemorrhage had a positive significant correlation with air pressure (P=0.001, r=0.452) and a negative correlation with ambient temperature (P<0.001, r= - 0.457). Subarachnoid hemorrhage and ischemia were not related to the season or the month. It was also found that ischemic stroke had a significant positive correlation with geomagnetic field fluctuations. Subarachnoid hemorrhage was not associated with any of the variables, but intracerebral hemorrhage was significantly positively associated with air pressure and inversely associated with temperature.
Conclusion: This study illustrated that winter, low temperature, high air pressure and high geomagnetic fluctuations are associated with a higher risk of stroke. Therefore, the underlying physiopathological causes of this relationship should be carefully investigated in future studies.