A Review on Epigenome Editing using CRISPR-based Tools to Rejuvenate Skin Tissues

Genomic activity is controlled by a sophisticated series of cell functions known as the epigenome. The creation of tools capable of directly altering various processes is required to unravel this intricacy. Additionally, by employing tailored DNA-binding platforms connected with effector domains to serve as targeted transcription factors or epigenetic modifiers, it is possible to control the chemical modifiers that regulate the genome's activity. Neoplastic disorders have received the most attention in the study of epigenetics, though the epigenome's significance in a variety of disease processes is now well acknowledged. Researchers are inspired to investigate novel approaches to revert these pathogenic alterations to their normal patterns by considering the fact that the epigenome profile of individuals with aging skin cells or other skin disorders, including atopic dermatitis, differs from that of healthy individuals. Here in this review, we discuss the use of CRISPR/dCas9 as a cutting-edge and flexible tool for fundamental studies on chromatin structure, transcription regulation, and epigenetic landscapes, as well as the potential of this method in these fields. Furthermore, we review on common and recently invented methods to make epigenetic alterations possible in daughter cells after any mitotic differentiations. In the very near future, CRISPR-based epigenomic editing will become a potent tool for comprehending and regulating biological functions

Occurrence of Bacillus cereus in beef burger marketed in Tehran, capital of Iran

Introduction: Beef burgers made in Iran contain various compounds such as meat, cereals flour, as well as some spices which can be contaminated with Bacillus cereus, causing gastroenteritis in the consumer. This study is focused on occurrence of B.cereus in beef burgers marketed in Tehran, capital of Iran. Methods and Results: In this cross-sectional study, a total of 80 samples of different types of beef burgers marketed in Tehran, Iran were randomly collected based on their percentage of meat content, including 30% (n=25), 60% (n=40) as well as 90% (n=15). The samples were analyzed microbiologically by routine culture assay and biochemical tests to find B.cereus. Data were analyzed statistically by Microsoft Office Excel 2010.  Twenty-five out of 80 (31.25%) beef burger samples were contaminated by B. cereus. Based on the percentage of meat content in the samples, the beef burger with 90% meat were significantly (p<0.05) more contaminated than the others. Also, the contamination rate was significantly (p<0.05) higher in summer compared to winter. Conclusion: This survey showed that the beef burgers supplied in Iran markets is main source of B.cereus that can cause disease in Iranian consumers. More attempts must be focused on cold-chain maintenance in production, distribution, and storage of the meat products

Population Size Estimation of Drug Users in Isfahan City (Iran) Using Network Scale-up Method in 2018

Background: To provide prevention programs and educate drug users (DUs), the estimation of their population is necessary. This study aimed to estimate the population size of this hidden group in Isfahan city as a metropolitan in Iran using the network scale-up method (NSUM).Methods: This cross-sectional study was performed in summer 2018 on 1000 people selected through a multistage sampling method based on 14 region of the municipality of Isfahan. The data collection tool was a questionnaire that was previously used in Dr. Banshi's national plan without any changes. The Cronbach's alpha value of the questionnaire was 0.826. Using correction factors such as transparency of response and the ratio of social network size used in previous national studies, the number of people with high-risk behaviors was estimated. The results were analyzed through NSUM based on survey analysis.Findings: Among all kinds of DUs, men were the largest consumers. The prevalence of use of opium, cannabis, heroin/crack, stimulants, ecstasy, hallucinogens, tramadol, zolpidem, tobacco, and drug injection was 2983, 2342, 613, 766, 86, 268, 1185, 213, 5869, 135 in 100000 people, among individuals of over 18 years of age. In both sexes, the prevalence of using opium and its nectar and illegal treatment with methadone and buprenorphine was higher in people of over 30 years of age, while the prevalence of consuming cannabis, ecstasy, tramadol, tobacco products, and stimulants was higher in the age group of 18 to 30 years.Conclusion: The results indicated that the prevalence of different DUs in Isfahan city, especially among men was higher than the reported average (especially in young men of 18-30 years of age). Since the prevalence of drug use varies based on the type of substance used among age groups, targeted preventive planning based on the type of drug used and age group is recommended

HIV Modes of Transmission in Sudan in 2014

Background: In Sudan, where studies on HIV dynamics are few, model projections provide an additional source of information for policy-makers to identify data collection priorities and develop prevention programs. In this study, we aimed to estimate the distribution of new HIV infections by mode of exposure and to identify populations who are disproportionately contributing to the total number of new infections in Sudan. Methods: We applied the modes of transmission (MoT) mathematical model in Sudan to estimate the distribution of new HIV infections among the 15-49 age group for 2014, based on the main routes of exposure to HIV. Data for the MoT model were collected through a systematic review of peer-reviewed articles, grey literature, interviews with key participants and focus groups. We used the MoT uncertainty module to represent uncertainty in model projections and created one general model for the whole nation and 5 sub-models for each region (Northern, Central, Eastern, Kurdufan, and Khartoum regions). We also examined how different service coverages could change HIV incidence rates and distributions in Sudan.Results: The model estimated that about 6000 new HIV infections occurred in Sudan in 2014 (95% CI: 4651-7432). Men who had sex with men (MSM) (30.52%), female sex workers (FSW) (16.37%), and FSW’s clients accounted (19.43%) for most of the new HIV cases. FSW accounted for the highest incidence rate in the Central, Kurdufan, and Khartoum regions; and FSW’s clients had the highest incidence rate in the Eastern and Northern regions. The annual incidence rate of HIV in the total adult population was estimated at 330 per 1 000 000 populations. The incidence rate was at its highest in the Eastern region (980 annual infections per 1 000 000 populations). Conclusion: Although the national HIV incidence rate estimate was relatively low compared to that observed in some sub-Saharan African countries with generalized epidemics, a more severe epidemic existed within certain regions and key populations. HIV burden was mostly concentrated among MSM, FSW, and FSW’s clients both nationally and regionally. Thus, the authorities should pay more attention to key populations and Eastern and Northern regions when developing prevention programs. The findings of this study can improve HIV prevention programs in Sudan

Estimating the Visibility Rate of Alcohol Consumption: A Case Study in Shiraz, Iran

Background: Network Scale Up (NSU) is applied in many settings to estimate the size of hidden populations.The visibility of alcohol consumption - as a hidden behavior - in Iran has not been yet set. Our aim is to estimatethe visibility factor (VF) of alcohol consumption in Iran which is an Islamic country in the Middle East.Methods: Ninety persons who had a history of alcohol consumption were recruited. Relationships in networkwere aligned in three main subgroups: immediate family, extended family, and non-family. According to thegame of contact methodology, participants answered questions about total and aware number of personsthey know in each relationship category. VF was calculated by dividing total number of people aware aboutthe respondent’s alcohol consumption by total number of respondent’s social network. The 95% confidenceintervals (CIs) were computed through bootstrapping.Findings: The mean and standard deviation (SD) of participants’ age was 32.9 ± 10.2, the sex ratio was 3.Overall VF (95% CI) was 40% (33% to 47%). VF was estimated at 44% and 23% among men and women’snetwork, respectively. The immediate family was the highest informed group, followed by non-family andextended family members.Conclusion: The visibility of alcohol consumption in Iran was not high. This is due to religious and legalprohibitions around i

Short-term effect of two education methods on oral health among hearing impairment children

BACKGROUND AND AIM: Poor oral health among children with impaired hearing has been reported frequently due to lack of communication skills and effective health educations. In this study, we assessed the effect of two training methods on short-term oral health outcomes among children with impaired hearing. METHODS: In this experimental study, 80 hearing impairment (HI) student aged 7-19 years old were randomized into two groups, one group watched a guided training video and the other group was educated by a dental model. The training sessions were weekly and continued for 1 month. A trained dentist examined all participants using O’Leary plaque index (PI) at baseline, 1-month, and 3-month visits. RESULTS: At baseline, the difference between the mean O’Leary PI in the video training and dental model training groups was not significant (34.3% vs. 35.6%). In the video training group, sharp decrease was seen at the 1-month visit (reinforcement periods), i.e., 18.7% (P = 0.001), followed by a slight increase at the 3-month visit (non-reinforcement periods), i.e., 19.1% (P = 0.100), respectively. On the other hand, in the dental model, a decreasing trend was seen 24.7% at 1-month (reinforcement periods) and 19.9% (P = 0.001) at 3-month visits (non-reinforcement periods). Overall, there were no significant differences between the two methods of training (P = 0.300). CONCLUSION: Both video and dental model effectively improve the oral health of children with HI in short term. Continuous school-based oral health education programs, particularly for HI children, need to be considered. KEYWORDS: Hearing Impairment; Plaque Index; Oral Health; Educatio

Multilevel Modeling of Longitudinal Data on Academic Evaluation of the Academic Staff of Kerman University of Medical Sciences, Iran

Background & Objective: In order to promote quality of education, teaching performances of all academic staff are evaluated by students every semester. This study aims to address the changing trend of staff scores in different semesters, and factors affecting it, in Kerman University of Medical Sciences, Iran, using multilevel modeling. Moreover, the results were compared to that of simple linear regression modeling. Methods: In the present analytical study, the scores of 336 academic staff of Kerman University of Medical Sciences during 2008 to 2012 were extracted from the students’ monitoring website. The tutor’s code was used for the identification of their scores in different semesters and was entered into the multilevel models. In order to investigate the effects of gender, work experience (in years), school (seven schools), and academic rank (master, assistant professor, associate professor, professor), the simple regression and multilevel models were compared. To study the significance of the random intercepts, the likelihood ratio test was used. In addition, to study the goodness of fit of the models, the Akaike information criteria (AIC), Bayesian information criteria (BIC), and the mean squared error (MSE) were used. Results: The results showed that time had a significant positive impact on the improvement of staff scores. However, the scores of male and female staff were not significantly different. The scores of professors were significantly higher than assistant professors. In addition, the score of dental school staff was significantly higher than that of medical school staff. The comparison of the goodness of fit of models showed that the multilevel modeling provided a better fit to the longitudinal data. In the linear regression model, variables such as work experience and academic rank (professors in comparison to assistant professors and nursing school staff in comparison to pharmacology school staff) were falsely considered significant, due to the lack of consideration of the dependence of longitudinal observations of the evaluation and correction of standard errors. Conclusion: The multilevel model, due to the consideration of the dependence of longitudinal observations of the evaluation, provides a better fit to data. Moreover, the incorrect use of the linear regression model, considering longitudinal observations to be independent, led to erroneous conclusions. The results of the present study, in terms of the goodness of fit of the models, showed a positive trend in scores of academic staff of Kerman University of Medical Sciences. In other words, the scores have improved over time. Keywords: Teacher evaluation; Student; Added value Evaluation; Longitudinal data; Multilevel modelin

The Application of Multilevel Linear Models and Generalized Estimating Equations to Evaluate the Quality of Professors’ Teaching in Various Semesters

Background & Objective: Improving the quality of education is the most central values of academic institutions and higher education. Given professors have played a decisive role in this context, -for assessing the quality of education- we need to evaluate the quality of instruction. One of the common methods for professors’ evaluation is evaluation by students, that it usually takes place at the end of each semester. With regard to the professors’ evaluation, data are of various types: the longitudinal data or repeated measurements over time, therefore to evaluate it; the quality of instruction should be used with longitudinal data analysis. However, such methods often are explained by complex methodology. This article introduces multilevel linear model and generalized estimating equations approach and value-added models by simple and applied expression as appropriate models for analysis of longitudinal data such as professors’ evaluation data. Keywords Teacher evaluation Value-added models Multilevel linear models Generalized estimating equations metho