Aims: This study was aimed to monitor the asymptomatic carriage of coagulase-positive staphylococcal bacteria among university male students and detect the prevalence of virulence marker genes that encode methicillin resistance (mecA) and Panton-Valentine leukocidin (PVL) toxin among the isolates. Methodology and results: Single nasal swaps were collected from 144 participating students who resided at four different locations within Al-Madinah city. A total of 112 Gram-positive staphylococcal isolates were recovered from the 144 participants (carriage rate of 77.8%). Coagulase-positive staphylococci were differentiated using duplex PCR amplification of the 16S rRNA and nuc genes and accounted for 30 isolates (carriage rate of 20.8%). These isolates were most prevalent in the northern and southern parts of Al-Madinah city, while the lowest numbers of isolates were detected in students of the eastern part. Coagulase-positive isolates were further phenotypically characterized for methicillin resistance by the disc diffusion method. Uniplex PCR assays were conducted to screen for mecA- and PVL toxin-encoding genes. The mecA gene was amplified from all 15 (50%) methicillin-resistant coagulase-positive isolates, while the PVL toxin-encoding gene was detected in 19 isolates (63.3%), 10 (33.3%) of which contained the mecA gene. Lastly, PCR amplification of the NRPS gene from coagulase-positive isolates revealed the absence of Staphylococcus argenteus, the recently discovered genetically divergent lineage of Staphylococcus aureus. Conclusion, significance and impact of study An elevated prevalence of coagulase-positive isolates harboring mecA and PVL virulence genes was observed compared with previous investigations. This poses a potential threat if they spread among the population, resulting in outbreaks of community-acquired infections.

Background: Styrene is one of the aromatic compounds used in acetonitrile–butadiene–styrene (ABS) producing petrochemicals, which has an impact on health of workers. Therefore, this study aimed to investigate the health risks of styrene emitted from the petrochemical industry in Iran. Methods: Air samples were collected based on NIOSH 1501 method. The samples were analyzed by the Varian-cp3800 gas chromatograph. Finally, risk levels of styrene's health effects on employees were assessed by the quantitative method of the U.S. Environmental Protection Agency (U.S. EPA) and the semiquantitative way by the Singapore Occupational Safety and Health Association. Results: Based on the results, the employees had the highest average exposure to styrene vapors (4.06x10-1 mg.(kg - day)-1) in the polybutadiene latex (PBL) unit. Therefore, the most top predictors of cancer and non-cancer risk were 2.3x10-4 and 7.26x10-1, respectively. Given that the lowest average exposure (1.5x10-2mg.(kg - day)-1) was in the dryer unit, the prediction showed a moderate risk of cancer (0.8x10-6) and non-cancer (2.3x10-3) for the employees. The EPA method also predicted that there would be a definite cancer risk in 16% and a probable risk in 76% of exposures. However, according to the semiquantitative approach, the rate of risk was at the “low” level for all staff. The results showed that there was a significant difference (p < 0.05) between the units in exposure and health risk of styrene (p < 0.05). Conclusion Given the high risk of styrene's health effects, appropriate control measures are required to reduce the exposure level.

Background: Styrene is one of the aromatic compounds used in acetonitrile–butadiene–styrene (ABS) producing petrochemicals, which has an impact on health of workers. Therefore, this study aimed to investigate the health risks of styrene emitted from the petrochemical industry in Iran. Methods: Air samples were collected based on NIOSH 1501 method. The samples were analyzed by the Varian-cp3800 gas chromatograph. Finally, risk levels of styrene's health effects on employees were assessed by the quantitative method of the U.S. Environmental Protection Agency (U.S. EPA) and the semiquantitative way by the Singapore Occupational Safety and Health Association. Results: Based on the results, the employees had the highest average exposure to styrene vapors (4.06x10-1 mg.(kg - day)-1) in the polybutadiene latex (PBL) unit. Therefore, the most top predictors of cancer and non-cancer risk were 2.3x10-4 and 7.26x10-1, respectively. Given that the lowest average exposure (1.5x10-2mg.(kg - day)-1) was in the dryer unit, the prediction showed a moderate risk of cancer (0.8x10-6) and non-cancer (2.3x10-3) for the employees. The EPA method also predicted that there would be a definite cancer risk in 16% and a probable risk in 76% of exposures. However, according to the semiquantitative approach, the rate of risk was at the “low” level for all staff. The results showed that there was a significant difference (p < 0.05) between the units in exposure and health risk of styrene (p < 0.05). Conclusion Given the high risk of styrene's health effects, appropriate control measures are required to reduce the exposure level.

Adherence to coronavirus disease 2019 (COVID-19) preventive guidelines (ACPG) is an important strategy to control the COVID-19 pandemic effectively. The present study aimed to identify and summarize the social determinants of ACPG among the general population. A comprehensive review was performed from December 2019 to February 2021 through searching electronic databases. Two independent reviewers assessed and selected relevant studies. Next, the characteristics and main findings of the included studies were summarized. Finally, the World Health Organization’s conceptual framework of social determinants of health was used to synthesize the identified social determinants of ACPG. Forty-one of 453 retrieved articles met the inclusion criteria. The study results showed different patterns of ACPG among various communities. Furthermore, 84 social determinants were identified and categorized into structural and intermediary determinants. ACPG is a set of complex behaviors associated with different individual sociodemographic and behavioral characteristics; living and working conditions; COVID-19 knowledge, attitudes, and risk perceptions; exposure to sources and information level; leisure activities; social support; trust; social norms; psychosocial well-being; socio-economic position; and the socio-economic and political context. Interventions to promote ACPG among the general population should consider the identified social determinants of ACPG.

Purpose: Brucellosis as a worldwide zoonotic illness affect domestic animals and humans doesn’t have any vaccine for the prevention of infection in humans yet. The aim of this study was to evaluate the specific immune response following the administration of glycine nanoparticles as adjuvant and delivery system of a chimeric antigen contained trigger factor, Omp31, and Bp26 in murine model. Materials and Methods: The chimeric antigen of Brucella was cloned and expressed in Escherichia coli (E. coli) BL21 (DE3). Purification and characterization of recombinant protein was conducted through Ni-NTA (nickel-nitrilotriacetic acid) agarose, SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), and Western blot. Nanoparticle characteristics including morphology, particle size distribution, zeta potential, protein retention rate, and release rate were measured in vitro. Subsequently, nanoparticle contained antigen was administered to mice and blood sample was taken to measured the antibody level. Results: The protein retention in the nanoparticles was successfully done and the nanoparticle characteristics were appropriate. The average size of glycine particles containing antigen was about 174 nm, and the absorption of protein was approximately 61.27% of the initial value, with a release rate of approximately 70% after 8 hours. Enzyme-linked immunosorbent assay result proved that the immunized sera of mice which were administered with nano-formula contains high levels of antibodies (immunoglobulin G) against recombinant chimeric antigen and also a high level of mucosal antibody (immunoglobulin A) in the oral group, which showed a desirable immunity against Brucella. Conclusion The results showed that chimeric antigen-loaded glycine nanoparticles can act as a vaccine candidate for inducing the cellular and humoral immune response against brucellosis.

Purpose: Chitosan is a natural polymer that has excellent properties include biocompatibility, biodegradability, no cytotoxicity, high charge density, low cost, mucoadhesive, permeation enhancing (ability to cross tight junction), and immunomodulating ability that makes the spectrum of its applicability much broader. This study was conducted to investigate the stabilizing, preservative and immunogenicity properties of N-trimethyl chitosan nanospheres (N-TMCNS). Materials and Methods: The tetanus toxoid (TT) was encapsulated into N-TMCNS and then characterized by scanning electron microscope, atomic force microscope, and dynamic light scattering. For stabilizer assay of N-TMCNS after storage of TT-N-TMCNS at different temperatures for 3 weeks, they were used for immunization of mice and different temperatures groups’ anti-TT-N-TMCNS production compared with other groups. Finally, the immunized mice were challenged with tetanus toxin. The preservation activity of TT-N-TMCNS against Escherichia coli was compared with thimerosal formulated TT. Results: Our results revealed that heat-treated TT-N-TMCNS could induce higher titer of neutralizing immunoglobulin G in compared to TT vaccine and was able to protect the mice better than TT vaccine in challenge test. Furthermore, N-TMCNS as a preservative inhibited the growth of E. coli more effective than thimerosal. Conclusion Overall, the obtained results indicated that the N-TMCNS is one of the best stabilizer and preservative agent that can be used in the formulation of TT vaccine.

Objective: Transcranial direct current stimulation (tDCS) and mindfulness practices have been proposed as a potential approach to improve executive functions (EFs) and reduce craving in persons with substance use disorders. Based on the neural mechanisms of action of each of these interventions, the combination of both non-pharmacological interventions might have additive effects. In the current study, the effects of tDCS combined with mindfulness-based substance abuse treatment (MBSAT) to improve EFs and reduce craving were investigated in early abstinent methamphetamine abuse. Methods: Eighty (youths aged between 18 and 21) early-abstinent methamphetamine users were randomly assigned to the research groups (tDCS group [n = 20], mindfulness group [n = 20], combined mindfulness-tDCS group [n =20], and sham group [n = 20]). Active tDCS (1.5 mA,20 min, 12 sessions) or sham tDCS was appliedover the left dorsolateral prefrontal cortex and the MBSAT protocol was used over twelve 50-min sessions. Results: Both in the post-test phase (immediately after the intervention) and follow-up phase (one month after the intervention), performance in most EFs tasks significantly improved in the combination group which received real tDCS ＋ MBSAT, as compared to baseline values and sham stimulation group. Similarly, a significant reduction in craving was observed after intervention inall treatment groups, but not the sham stimulation group. Interestingly, the increase in EFs and the reduction in craving post versus pre tDCS ＋ MBSAT intervention were correlated. Conclusion Findings from the current study provide initial support for the clinical effectiveness of combination tDCS ＋ MBSAT, possibly influencing cognitive/affective processes.

No abstract available.
Delivery of Health Care ; Global Health ; World Health Organization

Network scale-up is an indirect size estimation method, in which participants are questioned on sensitive behaviors of their social network members. Therefore, the visibility of the behavior affects the replies and estimates. Many attempts to estimate visibility have been made. The aims of this study were to review the main methods used to address visibility and to provide a summary of reported visibility factors (VFs) across populations. We systematically searched relevant databases and Google. In total, 15 studies and reports that calculated VFs were found. VF calculation studies have been applied in 9 countries, mostly in East Asia and Eastern Europe. The methods applied were expert opinion, comparison of NSU with another method, the game of contacts, social respect, and the coming-out rate. The VF has been calculated for heavy drug users, people who inject drugs (PWID), female sex workers (FSWs) and their clients, male who have sex with male (MSM), alcohol and methamphetamine users, and those who have experienced extra-/pre-marital sex and abortion. The VF varied from 1.4% in Japan to 52.0% in China for MSM; from 34.0% in Ukraine to 111.0% in China for FSWs; and from 12.0% among Iranian students to 57.0% in Ukraine for PWID. Our review revealed that VF estimates were heterogeneous, and were not available for most settings, in particular the Middle East and North Africa region, except Iran. More concrete methodologies to estimate the VF are required.
Africa, Northern ; Bias (Epidemiology) ; China ; Drug Users ; Europe, Eastern ; Expert Testimony ; Far East ; Female ; Humans ; Iran ; Japan ; Male ; Methamphetamine ; Methods ; Middle East ; Sex Workers ; Ukraine

OBJECTIVES: Two main digital signal processing technologies inside the modern hearing aid to provide the best conditions for hearing aid users are directionality (DIR) and digital noise reduction (DNR) algorithms. There are various possible settings for these algorithms. The present study evaluates the effects of various DIR and DNR conditions (both separately and in combination) on listening comfort among hearing aid users. METHODS: In 18 participants who received hearing aid fitting services from the Rehabilitation School of Shahid Beheshti University of Medical Sciences regularly, we applied acceptable noise level (ANL) as our subjective measure of listening comfort. We evaluated both of these under six different hearing aid conditions: omnidirectional-baseline, omnidirectional-broadband DNR, omnidirectional-multichannel DNR, directional, directional-broadband DNR, and directional-multichannel DNR. RESULTS: The ANL results ranged from −3 dB to 14 dB in all conditions. The results show, among all conditions, both the omnidirectional-baseline condition and the omnidirectional-broadband DNR condition are the worst conditions for listening in noise. The DIR always reduces the amount of noise that patients received during testing. The DNR algorithm does not improve listening in noise significantly when compared with the DIR algorithms. Although both DNR and DIR algorithms yielded a lower ANL, the DIR algorithm was more effective than the DNR. CONCLUSION: The DIR and DNR technologies provide listening comfort in the presence of noise. Thus, user benefit depends on how the digital signal processing settings inside the hearing aid are adjusted.
Hearing Aids* ; Hearing Loss ; Hearing* ; Humans ; Noise* ; Rehabilitation ; Signal Processing, Computer-Assisted