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Background and Objective: Breast cancer is one of the most important malignant tumors world -wide and the second common cancer in the females. Breast cancer is associated with a number of environmental factors and genetic damages. Ki67 is a proto-oncogene which is activated in cell proliferation process. Ki67 is important in prognosis and response to chemotherapy. The aim of this study was to investigate the Ki67 gene expression in patients with breast cancer by immunohistochemistry method. Materials and Methods: This descriptive laboratory study was conducted on 80 breast cancer specimens from patients admitted to the hospitals in Sabzevar, Iran during 2005-09. Samples were fixed in formalin, the tissue processing was done and sections were stained by Hematoxilin and Eosin method. The malignancy was diagnosed by two pathologists blindly. Over expression of ki67 was determined with the immunohistochemistry method. Slides were scored into negative, weak, average and strong based on percentage of cells which were stained. The Data were analyzed by SPSS-11.5, Chi-Square and Fisher’s exact tests. Results: Ki67 proliferative marker was observed in 37 (46.3%) specimens with breast cancer. Sensivity of staining was one positive (+) in 15 cases, two positive (++) in 14 cases and three positive (+++) in 8 cases. There was a significant relationship between Ki67 gene expression and tumor type and tumor staging (P<0.05), but there was no significant relationship between Ki67 gene expression and tumor grade. Conclusion: It is concluded that, ki67 is expressed mostly in invasive and developed breast cancer.

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Background and Objective: The etiology of childhood leukemia as the most common childhood malignancy remains largely unknown. This study was done to ascess the risk factors in childhood lymphoblastic leukemia in Shiraz-Iran. Materials and Methods: This case-control study was done on 141 children younger than 18 years suffering from acute lymphoblastic leukemia (ALL) whome resided at Fars Province of Iran during 2009. Patients were individually matched with 141 controls in respect to age, sex and residential area. Variables included: maternal age, parental education, father occupation, child birth weight and birth order, number of siblings, history of pet ownership including cat or dog, history of child day care attendance, history of leukemia in relatives, and history of mother diagnostic radiography during pregnancy. In order to evaluate the relationships between each variable and the risk of leukemia, odds ratio (OR) and 95% confidence interval (CI) were estimated using conditional logistic regression. Data were analyzed using SPSS-16 and Chi-Square test. Results: The agricultural occupation fathers in case and control were 17% and 5.7%, respectivley (P<0.01). The association between risk of childhood lymphoblastic leukemia with birth order≥3 (OR=5.939, 95% CI: 2.646-13.331, P<0.01), pet ownership (dog or cat) (OR=2.582, 95% CI: 1.265-5.269, P<0.009) and history of leukemia in first and second degree relatives (OR=3.5, 95% CI: 1.252-10.633, P<0.027) was significant. No relationship was found between birth weight, day care attendance, history of miscarriage, number of siblings and history of mother diagnostic radiology tests with risk of acute lymphoblastic leukemia. Conclusion: This study showed that father occupation, birth order, pet and history of leukemia in relation are risk factors of childhood acute lymphoblastic leukemia.

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Background and Objective: Impacted molars teeth, especially third molar, are important in most branches of medical sciences. The angular position of molar teeth is in side effects and therapeutic regiment. This study was conducted to determine the angle of the impacted mandibular third molars. Materials and Methods: This descriptive study was carried out on 429 patients (269 men and 160 women) selected for surgery on impacted mandibular third molar in the oral and maxillofacial surgery clinic in Gorgan, Iran during 2010-11. Pre-operative diagnosis was done by physical examination and OPG radiography. Demographic characterstics including age, gender, ethnicity, impaction angle were recorded for each subject. Data were analyzed using SPSS-16, independent t-test and chi-square test. Results: Totally, 480 impacted third molars were studied. Mean age of patients was 26.06±6.21 years. Impaction of the third molar was more prevalent among men (62.7%) than women (38.30%). Impacted mandibular third molar of 189 people (44.1%) were in left side in 200 people (46.6%) were in right side and in 40 people (9.3%) were bilateral. According to impaction angle, mesioangular (41.7%) and distoangular (3.5%) types had the highest and the lowest frequency, respectively. In bilateral cases, the mesioangular-mesioangular type (48.8%) was the most prevalent. The mesioangular type was the most prevalent in all ethnic groups. The most prevalent angular position of the impacted third molar was the mesioangular type in both sexes. Conclusion: This study showed that the most prevalent angular position of impacted mandibular third molar is the mesioangular type.

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Background and Objective: Antiepileptic drugs can partiality control or achieve the convulsion. There are controversial issues about the use and effect of ethanol to control epileptic convulsion seizers. This study was done to determine the effect of ethanol on microvascular alterations in the brain cortex of epileptic mice treated by valporic acid (VPA). Materials and Methods: In this experimental study, 36 BALB/c mice were allocated randomly into six groups including: 1-PTZ (Pentylenetetrazol), 2- Ethanol, 3- VPA+ PTZ, 4- ethanol + PTZ, 5-ethanol+ VPA+ PTZ and control groups. The animal brains were excluded and stained by Hematoxilin and eosin. Thirty-six optical microscopic field from each group were selected and microvascular count were determined. Immunohistochemical method was used for detection of injuries in the vascular brain tissue. Results: Mean number of brain microvascular cortex significantly increaed in PTZ+ethanol and PTZ+ethanol+VPA groups in compare to controls (P<0.05). Infiltration and thrombophlebitis were observed in vessels and cortical brain tissues in mice which received ethanol and PTZ. Proliferations in endothelial vascular cells were seen in PTZ and VPA+ethanol groups. Immunohistochemical method showed the endothelial cells of PTZ+ethanol groups were more stained in compare to the other experimental groups. Conclusion: Ethanol + PTZ cause cellular infiltration and damage to the cortical brain vessels although VPA reduces histological altheretions.

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Background and Objective: Some problems such as low viability and apoptosis after injection to the body because of exposure to toxic factors such as hypoxia, thermal stress, oxidative stress and food deprivation are encountered with stem cell application. It is suggested that preconditioning of the cells with cytotoxic factors before injection could enhance their efficiency. This study was done to determine the mesenchymal stem cell proliferation exposed to hypoxia by cobalt chloride. Methods: In this experimental study, Mesenchymal stem cells were isolated from rat bone marrow and cultured at least for four times. The cells were cultured in 96 well plates and treated with different concentration (0, 5, 10, 20, 50, 70, 90, 100, 120, 150 and 200 µM) of cobalt chloride for 6, 12, 24 and 46 hours. Cell proliferation was detected by MTT assay [3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide]. Results: The cells isolated from bone marrow were propagated easily in culture condition. The cells morphology was not altered after exposure to cobalt chloride. Preconditioning of mesenchymal stem cells with 120 µM for 6 hours, 20µM for 12 and 24 hours and 5µM for 48 hours significantly improved cell proliferation after hypoxia in cell culture (P<0.05). Conclusion: Hypoxia preconditioning increases proliferation of mesenchymal stem cell.

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Background and Objective: Sodium Arsenite is an environmental pollutant which can generate free radicals causing tissue damage. This study was done to evaluate the effect of Green Tea (GTE), as a strong antioxidant, on kidney tissue in mice treated with Sodium Arsenite. Methods: In this experimental study 24 adult male NMRI mice were randomly allocated into four groups including: control, GTE (100mg/kg/day), Sodium Arsenite (5mg/kg/day) and Sodium Arsenite + GTE, for 34 days, orally. Animals were scarified and left kidney was taken out, fixed, sectioned, processed and stained using Heidenhain'azan method. Using stereological technique the total volume of kidney, volume of cortex, medulla, proximal and distal tubule, renal corpuscle, gelomerelus, tuft and capillary, membrane and space of Bowman's capsule and length of proximal and distal tubule were determined. Creatinine, BUN and MDA serum samples were measured. Results: The mean of total volume of cortex, proximal tubule, distal tubule, renal corpuscle and gelomerolus, taft, Bowman's capsule space, size of epithelium and lumen of proximal and distal tubule were significantly reduced in Sodium Arsenite group compared to control (P<0.05). These parameters were significantly increased in the Sodium Arsenite + GTE group in comparison with Sodium Arsenite group (P<0.05). The creatinine, Blood urea nitrogen (BUN) and MDA were significantly increased in the Sodium Arsenite group in compared to the control group (P<0.05). These parameters were significantly reduced in the Sodium Arsenite + GTE group in comparison with Sodium Arsenite group (P<0.05). Conclusion: Green tea has a protective role in Sodium Arsenite induced nephrotoxicity.

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Background and Objective: Vitiligo is one of the most frequent skin disorders with a prevalence of 1-2% in different populations. Although many theories have been suggested for its pathogenesis, but the most popular hypotheses is the role of autoimmunity in Vitiligo. This study was done to evaluate the thyroid dysfunction and thyroid autoantibodies in patients with Vitiligo.

Methods: This case-control study was carried out on 45 patients with Vitiligo and 45 age- and sex-matched healthy individuals as control group. Age, gender, duration of the disease and type of Vitiligo were collected through a standard questionnaire. Thyroid autoantibodies including thyroglobulin antibody, anti- thyroglobulin and thyroid peroxidase antibody, and anti-TPO thyroid hormones Tetraiodothyronine (T4), Triiodothyronine (T3) and thyroid stimulating hormone (TSH) in Vitiligo patients and healthy volunteers were measeared.

Results: Serum level of T4 was significantly reduced in Vitiligo patient compared to controls (P<0.05). Serum level of T4 in 20% of Vitiligo patient and 2.2% of control cases was less the normal level. Anti-TPO in 14 (31.1%) of Vitiligo patient and 6 (13.3%) of controls were higher than normal range (<60 IU/m) (P<0.05). Serum level of anti- thyroglobulin was significantly higher in those with Vitiligo in compared to controls (P<0.05).

Conclusion: This study showed that the thyroid dysfunction particularly hypothyroidism and anti-TPO is more common in Vitiligo patients.

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Background and Objective: Familial hypercholesterolemia (FH) is one of the most common inherited familial diseases that cause lipid accumulation in tendons and arteries by increasing the level of low density plasma lipoprotein (LDL). The main cause of FH is a mutation in the low-density lipoprotein receptor (LDLR) gene. This study was performed to evaluate common mutations in LDLR gene in FH patients.
Methods: This descriptive study was performed on 100 patients with suspected familial hypercholesterolemia referred to Sepehr laboratory according to the Simon Broom international standard in Karaj city, Iran during 2015. After complate the questionnaire form and drawing the family tree, it was found that 17 of them had a history of disease in at least one of the first degree relatives. The presence of changes was investigated using PCR-SSCP method, and after identifying the suspected cases direct DNA sequencing was performed.
Results: Among of 17 patients with a history of FH disease, 13 patients had a heterozygote mutation in the LDLR gene. Mutations included: c.97C>T, c.445G>T, c.651-653 (DEL3), c.652-654 (DEL3), c.682G>T, c.925-931 (DEL7), c.936-940 (DEL5), c.986G>T, c.2054C>T, c.2177C>T and c.313+1G>A. Four patients did not have mutations in their LDLR gene. In two patients the common polymorphism c.1959T>C was identified.
Conclusion: The LDLR gene was involved in the development of FH in the study population. However, another gene or locus may be involved in the outbreak of this disease in the studied population.