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Load characteristics, in vitro bioaccessibility and health risk assessment of PM2.5�bounded heavy metals in indoor air of waterpipe and/ or cigarette cafes compared to smoking-free cafes
No full textSamples of PM2.5 particulates were collected from indoor air of 36 cafés, 14 cafés in which only water pipe (WS) was used, eight in which only cigarette was smoked (CC), six in which both waterpipe and cigarette were smoked (WCC), and eight cafés in which no smoking occurred (SFC) in Tehran. After that, the concentration of lead (Pb), cadmium (Cd), nickel(Ni), and chromium (Cr) was examined by atomic absorption spectrophotometer (AAS) (GF 5000, Australia). The results indicated that the ƩMetal concentration (Mean ±SD) in WCC, WC, CC, and SFC cafés were 1118.5±50.42, 663.64±40.79, 425.57±17.55, and 79.02±5.13 ng/m3, respectively. The mean bioaccessibility of Pb, Cr, Ni, and Cd was obtained as 39.7, 31.4, 7.35, and 74.6, respectively. The results of risk assessment indicated that exposure to heavy metals in the indoor air of smoking cafés of Tehran is considered high. © 2020, © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
Benchmarking of Monte Carlo model of Siemens Oncor® linear accelerator for 18MV photon beam: Determination of initial electron beam parameters
No full textOBJECTIVE: This study aims to benchmark a Monte Carlo (MC) model of the 18 MV photon beam produced by the Siemens Oncor® linac using the BEAMnrc and DOSXYZnrc codes. METHODS: By matching the percentage depth doses and beam profiles calculated by MC simulations with measurements, the initial electron beam parameters including electron energy, full width at half maximum (spatial FWHM), and mean angular spread were derived for the 10�10 cm2 and 20�20 cm2 field sizes. The MC model of the 18 MV photon beam was then validated against the measurements for different field sizes (5�5, 30�30 and 40�40 cm2) by gamma index analysis. RESULTS: The optimum values for electron energy, spatial FWHM and mean angular spread were 14.2 MeV, 0.08 cm and 0.8 degree, respectively. The MC simulations yielded the comparable measurement results of these optimum parameters. The gamma passing rates (with acceptance criteria of 1/1 mm) for percentage depth doses were found to be 100 for all field sizes. For cross-line profiles, the gamma passing rates were 100, 97, 95, 96 and 95 for 5�5, 10�10, 20�20, 30�30 and 40�40 cm2 field sizes, respectively. CONCLUSIONS: By validation of the MC model of Siemens Oncor® linac using various field sizes, it was found that both dose profiles of small and large field sizes were very sensitive to the changes in spatial FWHM and mean angular spread of the primary electron beam from the bending magnet. Hence, it is recommended that both small and large field sizes of the 18 MV photon beams should be considered in the Monte Carlo linac modeling. © 2019-IOS Press and the authors. All rights reserved
Comparison of the effect of sesame and almond oil on the incidence of striae gravidarum
Get PDFBackground: Striae gravidarum (SG) is one of the most common skin changes during pregnancy. Objectives: This study aimed to compare the effect of almond oil and sesame oil on the incidence of SG. Methods: A randomized controlled trial was conducted on 165 pregnant women referring to community health centers of Kashan, Iran. The participants in the two intervention groups received sesame oil or almond oil twice a day, from the 16 th week to the end of the 36 th week of gestation. The manifestations of SG and its severity were recorded at the end of the study. Data analysis was performed using descriptive statistics, Chi-square, one-way analysis of variance, and logistic regression analysis. Results: SG occurred in 63.60, 60, and 58.20 in the almond, sesame oil and control groups, respectively. No significant difference was found in the incidence of striae between the three groups in the 36 th week of gestation (P = 0.837). None of the confounding variables could predict the occurrence of striae (P > 0.05). Conclusion: Neither sesame oil nor almond oil could significantly affect the occurrence of SG. Given the controversies between the studies, further studies are required to evaluate the effect of almond oil and sesame oil in the prevention of the SG
Older adults' barriers to use technology in daily life: A qualitative study
Get PDFBackground: Aging is associated with declines in individuals' physical and mental abilities. Technological assistance can improve older adults' independence, functional performance, and health. Objectives: The purpose of this study was to explore experiences regarding barriers to use technology in daily life among older adults. Methods: This qualitative study was conducted on twenty older adults referred to Urban Comprehensive Health Service Centers, Kashan. The main interview questions were What does the word technology bring to your mind? Which electrical household appliances do you use during your daily life? and What are the barriers you experience during the use of technology? Data were collected through semi-structured interviews and analyzed using conventional content analysis. Results: Three main themes emerged: aging-related barriers (physical and mental limitations), individual barriers (educational limitations, limited access to technology, and unfavorable attitudes toward technology), and barriers related to the appliances. Conclusion: Older adults experience multiple barriers to use technology in their daily life. Educational interventions may enhance older adults' utilization of technology in daily life of this population
The survivin molecule as a double-edged sword in cellular physiologic and pathologic conditions and its role as a potential biomarker and therapeutic target in cancer
No full textSurvivin is a member of the family of apoptosis inhibitory proteins with increased expression level in most cancerous tissues. Evidence shows that survivin plays regulatory roles in proliferation or survival of normal adult cells, principally vascular endothelial cells, T lymphocytes, primitive hematopoietic cells, and polymorphonuclear neutrophils. Survivin antiapoptotic role is, directly and indirectly, related to caspase proteins and shows its role in cell division through the chromosomal passenger complex. Survivin contains many genetic polymorphisms that the role of some variations has been proven in several cancers. The �31G/C polymorphism is one of the most important survivin mutations which is located in the promoter region on a CDE/CHR motif. This polymorphism can upregulate the survivin messenger RNA. In addition, its allele C can increase the risk of cancers in 1.27-fold than allele G. Considering the fundamental role of survivin in different cancers, this protein could be considered as a new therapeutic target in cancer treatment. For this purpose, various strategies have been designed including the prevention of survivin expression through inhibition of mRNA translation using antagonistic molecules, inhibition of survivin gene function through small inhibitory molecules, gene therapy, and immunotherapy. In this study, we describe the structure, played roles in physiological and pathological states and genetic polymorphisms of survivin. Finally, the role of survivin as a potential target in cancer therapy given challenges ahead has been discussed. © 2019 Wiley Periodicals, Inc
Micro-RNA-incorporated electrospun nanofibers improve osteogenic differentiation of human-induced pluripotent stem cells
No full textSmart scaffolds have a great role in the damaged tissue reconstruction. The aim of this study was developing a scaffold that in addition to its fiber's topography has also content of micro-RNAs (miRNAs), which play a regulatory role during osteogenesis. In this study, we inserted two important miRNAs, including miR-22 and miR-126 in the electrospun polycaprolactone (PCL) nanofibers and after scaffold characterization, osteoinductivity of the fabricated nanofibers was investigated by evaluating of the osteogenic differentiation potential of induced pluripotent stem cells (iPSCs) when grown on miRNAs-incorporated PCL nanofibers (PCL-miR) and empty PCL. MiRNAs incorporation had no effect on the fibers size and morphology, cell attachment, and protein adsorption, although viability and proliferation rate of the human iPSCs were increased after a week in PCL-miR compared to the empty PCL. The results obtained from alkaline phosphatase activity, calcium content, bone-related genes, and proteins expression assays demonstrated that the highest osteogenic markers were observed in iPSCs grown on the PCL-miR compared to the cells cultured on PCL and culture plate. According to the results, miR-incorporated PCL nanofibers could be considered as a promising potential tissue-engineered construct for the treatment of patients with bone lesions and defects. © 2019 Wiley Periodicals, Inc
Zinc supplements and bone health: The role of the RANKL-RANK axis as a therapeutic target
Get PDFBackground: To this day, empirical data suggests that zinc has important roles in matrix synthesis, bone turnover, and mineralization and its beneficial effects on bone could be mediated through different mechanisms. The influence of zinc on bone turnover could be facilitated via regulating RANKL/RANK/OPG pathway in bone tissue. Therefore, the aim of the study was to conduct a review to investigate the possible effect of the zinc mediated bone remodeling via RANKL/RANK/OPG pathway. Methods: A comprehensive systematic search was performed in MEDLINE/PubMed, Cochrane Library, SCOPUS, and Google Scholar to explore the studies investigating the effect of zinc as a bone remodeling factor via RANKL/RANK/OPG pathway regulation. Subsequently, the details of the pathway and the impact of zinc supplements on RANKL/RANK/OPG pathway regulation were discussed. Results: The pathway could play an important role in bone remodeling and any imbalance between RANKL/RANK/OPG components could lead to extreme bone resorption. Although the outcomes of some studies are equivocal, it is evident that zinc possesses protective properties against bone loss by regulating the RANKL/RANK/OPG pathway. There are several experiments where zinc supplementation resulted in upregulation of OPG expression or decreases RANKL level. However, the results of some studies oppose this. Conclusion: It is likely that sufficient zinc intake will elicit positive effects on bone health by RANKL/RANK/OPG regulation. Although the outcomes of a few studies are equivocal, it seems that zinc can exert the protective properties against bone loss by suppressing osteoclastogenesis via downregulation of RANKL/RANK. Additionally, there are several experiments where zinc supplementation resulted in upregulation of OPG expression. However, the results of limited studies oppose this. Therefore, aside from the positive role zinc possesses in preserving bone mass, further effects of zinc in RANKL/RANK/OPG system requires further animal/human studies. © 2019 Elsevier Gmb
Body image before and after coronary artery bypass graft surgery: Comparison and its contributing factors
Get PDFBackground: Cardiovascular diseases are the leading cause of death in the world. Coronary artery bypass graft (CABG) surgery is among the treatment options for coronary artery disease. However, it is associated with significant physical and psychological problems. This study sought to compare body image before and after the surgery and to determine its contributing factors. Methods: This comparative study was conducted in 2017 on a sample of 140 patients consecutively recruited from Shahid Beheshti hospital, Kashan, Iran. Body image was assessed before and 4 weeks after the surgery (T1 and T2) using Multidimensional Body-Self Relations Questionnaire. The independent-sample and paired t tests, one-way analysis of variance, Pearson correlation test, and multiple regression were conducted for data analysis. Results: Participants' mean score of body image was 139.60 ± 13.21 at T1 and 160.25 ± 7.75 at T2 and the variation was statistically significant (p = 0.05). Conclusions: Candidates for CABG have poor body image. After the surgery, their body image improves significantly. Healthcare providers need to employ programs to improve body image among these patients. © 2020 The Author(s)
Prevention of occupational traumas by developing an ergonomic design and modifying farmers' postures in walnut gardens of Tuyserkan, Iran
Get PDFBackground and Objectives: Occupational traumas are known as work-related disorders, associating with some sorts of factors such as repetitive tasks, body postures, workstations, and hand tools. These traumas cause various problems for both workers and employers. Due to occupational hygiene considerations, problems such as cumulative trauma disorders, occupational trauma, low back pain (LBP), and work-related musculoskeletal disorders should be controlled. In this regard, ergonomic interventions can have efficient outcomes toward controlling occupational traumas. In this study, the focus was on working at some walnut gardens in the city of Tuyserkan in Iran, to reach an ergonomic analysis base, in which hand tools were assessed. The main objective was to develop a new ergonomic design for workers using hand tools. Subjects and Methods: In this cross-sectional study, 19 workers participated and filled out the Nordic Musculoskeletal Questionnaire (NMQ). Their body postures during harvesting walnuts were evaluated by the Ovako Working Posture Analysis System method. Hand tool analysis was also performed by ergonomic risk assessments. Results: The results showed that 15 of the farmers experienced some sorts of trauma during the harvest while using traditional hand tools. The results also emphasized that 61.5 of the workers' body postures should be modified. In addition, according to the NMQ, the most common problems among workers were wrist disorders, LBP, and knees' and shoulders' disorders. Conclusions: Considering experimental data, a new device was developed in which the weight, adjustability, and form of hand tools were modified under ergonomic considerations. The benefits of the new design were confirmed by SOLIDWORKS software. Since this new device helps farmers to decrease extra force exertion in awkward postures, it is expected to improve farmers' condition while using it
The association between time intervals in emergency medical services and In-hospital mortality of trauma patients
Get PDFContext: While the clinical practice recommends field stabilization in trauma patients, in some situations, the speed of transport is crucial. Aims: This study aimed to evaluate the association between emergency medical services (EMS) time intervals (response time RT, scene time ST, and transport time TT) and in-hospital mortality in trauma patients in Tehran, the largest metropolis of Iran. Settings and Design: A prospective cohort study was conducted between May 2017 and April 2018. Methods: All EMS operations related to trauma events in the Tehran city that were transferred to three targeted major trauma centers were included. Statistical Analysis: Logistic regression analysis was used to assess the relationship between EMS time intervals and other risk factors of trauma death. Results: A total of 14,372 trauma patients were included in the final analysis. In-hospital mortality occurred in 225 (1.6%) patients. After adjustment for confounding variables, older age (odds ratio OR = 1.04/year), female gender (OR = 2.16), low Mechanism, Glasgow Coma Scale (GCS), age, and arterial pressure score (OR = 0.84 for each unit), low GCS (OR = 0.56 for each unit), longer ST (OR = 1.17/10 min), and longer TT (OR = 1.21/10 min) were found to be risk factors for death in trauma. Conclusions: Our study showed that in-hospital mortality of trauma patients correlated with longer EMS ST and TT, but the RT was not associated with mortality. Our results recommend that the EMS system should consider ST and TT rather than RT, as indexes of quality control in prehospital care of trauma patients