Background: Ethambutol (EMB) resistance is a major concern in patients with tuberculosis (TB). The aim of this study was to determine the frequency rate of mutations in the embB 306 gene of Mycobacterium tuberculosis (M. tuberculosis) resistant to EMB, based on a systematic review and meta-analysis. Methods: Thirty-seven original articles (1997–2015) that have been published in valid databases were considered for this research. The articles were systematically reviewed for the prevalence and rate of mutations in embB 306 in EMB-resistant M. tuberculosis. Data were analyzed using meta-analysis and random effects models (CI 95%, P < 0.10). Results: With a 6,931 sample size in 37 original articles, the lowest rate was related to EMB resistance that was observed in 2014 with 0.05 (95% CI: 0.04–0.07) and the highest prevalence rate was 0.84 (95% CI: 0.68–1.01), observed in 1997. Lowest and highest prevalence rates of embB 306 gene mutation in M. tuberculosis were 0.03 (95% CI: 0.01–0.07) in 2014 and 0.78 (95% CI: 0.71–1.84) in 2005, in the USA, respectively. Conclusions: The present study revealed the prevalence and association of mutations in the embB 306 gene of M. tuberculosis with resistance to EMB. Detecting EMB-resistant M. tuberculosis can help in controlling and correcting the administration of drugs for patients with TB.

Background: Molar--incisor hypomineralization (MIH) could be appeared in condition of calcium (Ca²⁺) disorders. Body height is an index of growth health monitoring in child that may be assumed by calcium metabolism. This study was designed to compare the body height of 8--9 years old schoolchildren with MIH and control group. Methods: This cross-sectional study was carried out by examination of 606 Iranian healthy schoolchildren for recording enamel defects and body height measurements by a single trained examiner. Putative etiological factors were evaluated using the structured questionnaire. The questionnaire was about maternal, prenatal, and postnatal factors. Statically analysis was done using t-test and Chi-square test in SPSS 22. Results: The prevalence of MIH in the schoolchildren was 52.9%. Prevalence of MIH significantly was higher in girls. Most of maternal and child's parameters appeared to have no significant correlation with MIH except birth weight, antibiotic therapy, maternal disease in pregnancy, and medication (P < 0.05). Conclusions: In spite of lower body height in schoolchildren with MIH, there was not any significant correlation between them.

The world is combating a common and invisible enemy severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), a highly transmissible virus responsible for serious respiratory illness coronavirus disease-2019 (COVID-19). As with all respiratory viruses, public health measures are focused on contact tracing, isolation, and treatment of affected individuals, who have respiratory symptoms. However, it is spreading efficiently, and it can be explained from its stealth transmission from presymptomatic and asymptomatic individuals. Droplet and contact precautions are followed universally. Healthcare workers are at higher risk of acquiring infection and they are additionally required to follow airborne and eye protection. Recent studies indicate viral particles can be isolated from many body fluids including feces, saliva, semen, and tears, suggesting transmission could be possibly occurring through some of these routes as well. We have done an evidence-based review of all potential modes of transmission and discussed preventive measures to stop the spread. There is an urgent need for educating the healthcare professionals, governments, and public regarding other potential modes of transmission. Strict preventive measures need to be used to stop the spread.

Background: Quality of work life (QWL) is considered as a universal concept in human resource management and organizational development, and its promotion is the key to the success of organizations' management. Therefore, the present study aimed to evaluate the QWL in Iran through systematic review and meta-analysis. Methods: In this study, all articles related to the QWL in Iran during the years 2011–2017 were systemically reviewed by searching national and international databases such as Science Direct, PubMed, Scopus, Web of Science, Springer, SID, Magiran, Barakat Knowledge Network System, Medlib, and the Google Scholar search engine using valid keywords. The results of the studies were combined using the random effects model. The heterogeneity of studies was studied using the I2 index. Data analysis was done using STATA ver 11. Results: The mean QWL score of 15,323 samples were 60.13, 36.80, 76.19, 58.90, 68.78, 50.69, 32.24, 8.01, 70.63, 39.70, and 44.41 based on Walton, Casio, Sirgy, Mirsepasi, SF-36, Ghasem zadeh, Dehghan, Dargahi, NIOSH, Venlar, Quality of nursing work life questionnaires, respectively. Meta-regression showed that the QWL of employees had no significant relationship with the sample size and years of research. Conclusions: The mean score of QWL in Iranian employees was 56.90, with the highest and the lowest score for the questionnaire.