Effects of Lifestyle and Environmental Factors on the Risk of Acute Myeloid Leukemia: Result of a Hospital-based Case-Control Study.

BACKGROUND: Acute myeloid leukemia (AML) is a common malignancy in adults. A vast variety of environmental and lifestyle factors play a role in AML incidence. This study aimed to assess the factors related to AML. STUDY DESIGN: A case-control study. METHODS: This case-control study was performed on 137 AML cases during 2018-2021 at Beheshti Hospital in Hamadan, Iran, and 137 gender/age-matched controls. A questionnaire including 12 items was used to obtain information about lifestyle and environmental factors. A univariate and multiple variate logistic regression was used to estimate the odds ratios (OR), and a 95% confidence interval (CI) was used to investigate the relationship between the studied variables and the incidence of AML. RESULTS: Based on findings, 62 (45.3%) out of the 137 leukemic cases were male and 75 (4.7%) were females. A statistically significant increased risk for AML was found with regard to prior usage of cytotoxic agents (OR: 8.00, 95% CI 1.01, 63.9, P=0.050), family history of malignancies (OR: 3.62, 95% CI: 1.65, 7.92, P=0.001), exposure to electrical power (OR: 3.22, 95% CI: 1.52, 6.81, P=0.002), and history of mental diseases (OR: 8.50, 95% CI: 3.64, 19.80, P=0.001). It was found that the AML incidence had no association with age, gender, radiation therapy, cigarette smoking, prior chemotherapy, congenital disorders, exposure to chemical agents, history of infectious mononucleosis, exercise, and blood transfusion (P>0.05). CONCLUSION: The current results suggested that cytotoxic agents, family history of malignancy, mental disorders, and exposure to electrical power could play a role in AML incidence.

Self-rated vocal complaints relationship to Vocal Tract Discomfort and Singers Voice Handicap Index in Iranian religious singers.

PURPOSE: The religious singing is a popular group of professional voice users in Iran which is performed in a sadness form to persuade the audiences to cry and think to holy persons. This style has its own unique vocal demands and abuses. Therefore, the present study, for the first time, aimed to investigate the prevalence of self-reported vocal complaints, vocal discomfort symptoms, and its effects on the vocal-related life of the Iranian religious singers. METHODS: In a cross-sectional study, 62 religious singers (28 women, 34 men) completed Singers Voice Handicap Index (SVHI), Vocal Tract Discomfort (VTD), and also a non-standard self-rated vocal complaint question. Spearman correlation test was applied to analyze correlations. Furthermore, 39 non-singers (18 women, 21 men) as a control group participated in this study. RESULTS: The religious singer's mean score of the SVHI test was 34.84 (SD = 24.89). According to the self-rated vocal complaint question, almost 80% of the participants reported mild to the severe vocal complaints that was significantly higher than control group which was about 10%. The self-rated complaints indicated a significant positive correlation with the SVHI and the VTD reported by singers (p ≤ 0.001). The mean scores of the VTD symptoms in singers were significantly greater than control group. There was also a significant positive correlation between the two VTD and SVHI tests (p ≤ 0.001). CONCLUSION: Religious singers are at a great risk of developing voice problems. Therefore, their vocal demands and requirements need to be followed precisely. The SVHI and VTD tests should also be considered as two efficient tools for religious singers.

In vitro Comparison of the Accuracy (Precision and Trueness) of Seven Dental Scanners.

STATEMENT OF THE PROBLEM: The mechanisms of operation of dental scanners are based on different technologies. Considering these differences, there are many types of scanners available in the market. PURPOSE: This in vitro study aimed to compare the accuracy (precision and trueness) of seven commonly used dental scanners. MATERIALS AND METHOD: In this in vitro experimental study, the accuracy of 7 common extra oral scanners (Sirona ineos inLab, Sirona X5, Dentium, Imes Icore 350I, Amann Girrbach, 3shape D700, and 3Shape E3) were evaluated. Each of scanners performed 7 scans of implant abutment of SIC (SIC MAX.GH1). Data from each scanner were then compared to data received from 3Shape Trios intra oral scanner as a reference. For evaluating the accuracy of each scanner, trueness and precision was evaluated. Collected data were analyzed using Kruskal Wallis and Bonferroni tests via SPSS version 22. RESULTS: Descriptive statistics showed the best trueness was for 3Shape E3 scanner with the average of 35.37µm and the worst trueness belonged to Sirona x5 scanner with the average of 51.75µm. Furthermore, the best precision was achieved for 3Shape E3 scanner with the average of 35.34, while the lowest precision was detected in 3Shape D700. The scanners had statistically significant differences with each other in terms of trueness and precision (p<0.05). CONCLUSION: Based on the results of this study, the extra oral scanner, 3shape E3, had the best trueness and precision. The lowest amount of trueness among the studied scanners was for the extra oral scanner, Sirona x5, and the lowest precision was for scanner 3shape D700.

Marginal Fit of Temporary Restorations Fabricated by the Conventional Chairside Method, 3D Printing, and Milling.

Objectives: This study aimed to compare the marginal fit of temporary restorations fabricated by the conventional chairside method, 3D printing, and milling. Materials and Methods: In this in vitro, experimental study, 14 temporary restorations were conventionally fabricated over an implant abutment and analog that had been mounted in a phantom model at the site of canine tooth, using auto-polymerizing acrylic resin and putty index. In digital manufacturing, the original model was scanned, and the final restoration was designed. Fourteen temporary restorations were milled out of polymethyl methacrylate (PMMA) blocks, and 14 others were printed by a 3D printer. Temporary crowns were placed on the abutment, and images were obtained from specific areas under a stereomicroscope at x100 magnification to measure the amount of marginal gap. Data were analyzed using one-way ANOVA and Tukey's test (α=0.05). Results: The mean marginal gap values for the temporary crowns in the 3D printing, milling, and chairside groups were 91.40, 75.28 and 51.23 µm, respectively. The crowns that were conventionally fabricated chairside exhibited the lowest marginal gap, and the difference in this respect was significant among the three groups (P<0.05). Conclusion: Temporary crowns fabricated by the chairside method showed significantly smaller marginal gap; however, the marginal gap of all three groups was within the clinically acceptable range.

The Epidemiology of Aggression and Associated Factors among Iranian Adult Population: A National Survey.

BACKGROUND: This survey was conducted to determine the level of aggression among the Iranian adult population and underlying predisposing factors. STUDY DESIGN: A cross-sectional study. METHODS: This cross-sectional study included 10,957 participants, involving 23 out of the 31 provinces of Iran in 2019. The outcome of interest was aggression, evaluated by the Buss & Perry aggression questionnaire. The association between aggression and 34 demographic, behavioral, social, and cultural characteristics was assessed using simple and multiple linear regression. RESULTS: The overall mean (SD) score of aggression was 77.10 (22.53). Based on the severity of aggression, the participants were categorized into four groups as follows: 2,464 (23.1%) nonaggressive, 4,692 (43.9%) mild, 3,071 (28.8%) moderate, and 454 (4.2%) severe aggressive. Aggression was more likely to occur in people with the following characteristics: younger ages, having several siblings, lower ranks of birth, having an intimate friend of the opposite sex, having an aggressive father/mother, history of parental divorce, interest in watching action/porn movies, listening to music, history of escape from home/school, using neuropsychiatric drugs, using illicit drugs, history of suicidal thoughts/attempt, and family conflict and hostility. Aggression was less likely to occur with the following characteristics: reading, regular physical exercise, the ability to control anger, regular prayer, adherence to avoid lying, respect to other people's rights, sexual satisfaction, and attachment to parents. CONCLUSION: A majority of the population has some degree of aggression. Aggression is a multifactorial behavior corresponding with several demographical, social, cultural, and religious factors, some of which back to early childhood events.

Risk of Acute Lymphoblastic Leukemia: Results of a Case-Control Study.

Background: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Different environmental factors might be effective in the occurrence of this malignancy during childhood. The aim of this study was to find environmental risk factors in childhood ALL in Hamadan, Iran. Methods: This case-control study was done in 2015-2018 on 125 children younger than 15 years of age suffering from ALL. Patients were matched with 130 controls with respect to age, gender, and residence location. The identification of risk factors for ALL was sought based on the comparison of studied variables between case and control individuals. Results: A statistically significant increased risk for ALL was found with regard to type of delivery (OR: 0.43, 95% CI: 0.20 - 0.92, p˂0.02), childcare (OR: 4.58, 95% CI: 0.95 - 22.20, p˂0.04), birth weight (OR: 1.44, 95% CI: 1.53 - 2.21, p˂0.006), father's education level (OR: 2.67, 95% CI: 1.10 - 6.45, p˂0.02), and father's job (OR: 0.2 95% CI: 0.08 - 0.51, p˂0.001). Also observed were increased odds for ALL regarding male gender, mother's high education level, mother's freelance job, and medium or high family income. No association with ALL incidence was observed for age, gender, breastfeeding, mother's age at pregnancy, malignancy in first- or second-degree relatives, or mother's use of hair dye during pregnancy (p> 0.05). Conclusion: This study showed that father's education level, father's job, delivery type, birth weight, and childcare can play a role in the incidence of childhood ALL.

Survival prediction of gastric cancer patients by Artificial Neural Network model.

AIM: This study aims to predict survival rate of gastric cancer patients and identify the effective factors related to it, using artificial neural network model. BACKGROUND: Gastric cancer is the most deadly disease in north and northeast provinces of Iran. A total of 430 patients with gastric cancer who referred to Baghban clinic in Sari, from early November 2006 to late October 2013 were followed. METHODS: A historical cohort of patients who referred to Baghban Clinic, the cancer research center of Mazandaran University of Medical Sciences in Sari, from early November 2006 to late October 2013 was studied. Three groups of variables (demographic, biological and socio-economic) were studied. Survival rate and effective factors on survival time were calculated using Kaplan-Meier methods and artificial neural networks and the best network structure were chosen using the mean square error and ROC curve. All analyses were performed using SPSS v.18.0 and the level of significance was selected α=0.05. RESULTS: In this research, the median survival time was 19±2.04 months. The 1 to 5-year survival rates for patients were 0.64, 0.44, 0.34, 0.24 and 0.19, respectively. The percentage of right predictions of the selected network and the area under the ROC curve were 92% and 94%, respectively. According to the results, the type of treatment, metastasis, stage of disease, histology grade, histology type and the age of diagnosis were effective factors on survival period. CONCLUSION: the 5 years survival rate of gastric cancer patients in Mazandaran is lower than other provinces which could be due to the delay in diagnosis or patient's referral. Therefore, the use of screening methods and early diagnosis could be influential for improving survival rate of these patients.