[ effect of allopurinol on high glucose- induced neurotoxicity in PC12 cells]

Background and Aim: hyperglycemia which occurs in diabetes is one of the main factors which can lead to serious complications such as diabetic neuropathy. There is evidence that allopurinol has neuroprotective effect against many types of damaging stimuli. The present study investigated the effects of allopurinol on high glucose induced neurotoxicity in PC12 cells as a suitable in-vitro model for evaluation of neuronal functions

Material and Methods: neurotoxicity was induced by high glucose concentration, and cells were exposed to allopurinol in the presence or absence of high glucose concentration. Cell viability was assessed by MTT assay. Biochemical markers of oxidative stress were investigated by measurement of lipid peroxidation [LPO], total thiol groups, and total antioxidant power [TAP]

Results: the present results indicated that allopurinol significantly inhibited high glucoseinduced cell death in PC12 cells. Furthermore, treatment with allopurinol decreased lipid peroxidation level. It also increased the total thiol groups and TAP

Conclusion: these findings showed protective effects of allopurinol on HG-induced cell death in PC12 cells, which may be related to its antioxidant effect and inhibition of oxidative stress

[Relationship between rainfall and temperature with the incidence of cancer in Golestan Province, northern Iran]

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

[ cleaning efficacy of manual files compared with two rotary instruments in the root canal of permanent molars: an in vitro study]

Rotary files may be cause anatomical changes in apical area. The aim of this study was evaluation of maintenance of the canal's curve using Flex Master and Protaper rotary instruments. In this in vitro study, we used 30 mesiobuccal roots of first permanent maxillary molars with a mean length of 18-23 milimeters and a mean curve of 15-40 degrees. Sampling was simple and the specimens were divided into two groups of fifteen. In each group, the canals were prepared by crown down method after the access step. Then they were prepared using Flex master and Protaper according to their company's instruction. After finishing the preparation steps, hand instrument number 30 was placed in the canals and under the same primary condition we evaluated the final angle by digital radiographic system. For evaluation of the results, we used variance analysis, t test and covariance analysis. The mean angle of apical transportation after using two Flexmaster and Protaper rotary systems was 6/19 +/- 3/07 and 5/52 +/- 2/87 degree, respectively. The mean apical transporation using the Flexmaster system was more than Protaper system but the difference between them was insignificant [P>0/ 05]. Because of using these two rotary systems, we had apical canal transportation. This transportation by using Flexmaster system was more than the Protaper system, but it was not significant