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Adsorption behavior of uracil on external surface of MgO nanotubes: A new class of hybrid nano-bio materials
No full textIn this study, geometries, binding, optical and electronic features and charge-transfer characteristics of magnesium oxide nanotubes (MgONTs) interacting with uracil pyrimidine were evaluated in both vacuum and solvent (water and toluene) environments by using density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations. The binding energy of uracil was estimated to be in a range of �0.543 to �1.864 eV in vacuum, �0.347 to �1.709 eV in toluene, and �0.193 to �1.592 eV in water environments. Furthermore, the values of the binding and reaction energies are all negative meaning that the binding of uracil on MgONT is energetically favorable and the synthesis of the complex structure is possible. The results illustrate that the adsorption energy values of uracil on MgONT also follow the order of vacuum > toluene > water. Our analysis demonstrates that solvent polarity is so significant on the stability and reactivity of uracil. In contrast to vacuum and toluene environments, the dipole moment value of MgONT in water environment was significantly increased upon adsorption of uracil. Our findings illustrate that MgONT was more sensitive for detecting the uracil in vacuum environment than water and toluene environments to exploit as a biochemical sensor. © 202
Effect of intensity and time ultrasound on yield and functional properties of extracted �-glucan of oat flour
No full text�-glucans are non-starch polysaccharides and water soluble hydrocolloids, Apart from being nutritionally important, �-glucans show an important technological role as thickening, stabilizing, emulsification, gel-forming component and fat substitute in the dairy products, bakeries, meats, pharmacy, cosmetics, and chemical industries, and feed production. The extraction of cereals �-glucans is very difficult. Ultrasonic extraction, represents higher efficiency since this method is a cost- effective which shortens the extraction time,energy and solvent consumption compared to conventional methods..in this study the effect of intensity and time at four different powers (0, 200, 300, 400 w) in three time (0, 3.5 and 7 min) intrevals were investigated on the yield, recovery, color and the functional properties of extracted �-glucan.The results showed that the intensity and time of ultrasound were significant on yield, recovery, color, emulsion stability, water holding capacity, solubility �-glucan (p�0.05). With increasing ultrasonic intensity and time, extracted �-glucan yield, recovery, emulsion stability, water holding capacity increased. The highest extraction yield (3.34), solubility (75.67) were observed at power 400w for 7 minutes, Also the highest recovery (52.04), emulsion stability (69.06), water retention capacity (13.21 g /g), compared to blank sample at power 300w for 7 minutes. L*, a*and b* and were 76.66, 3.2, 3.2 respectively. © 2021 Tarbiat Modares University
Enhanced radiotherapy efficacy of breast cancer multi cellular tumor spheroids through in-situ fabricated chitosan-zinc oxide bio-nanocomposites as radio-sensitizing agents
No full textOverwhelming evidence has shown that three-dimensional multicellular tumor spheroids (MCTSs) as a mimic of in-vivo tumor can accurately exhibit cellular responses to treatments. So, we compared the capability of pure zinc oxide nanoparticles (ZnO-NPs) and chitosan-ZnO bio-nanocomposites (CS-ZnO BNCs) for enhancing the radiosensitization of MDA-MB-231 breast cancer cells (BCCs) in the 3D-MCTSs model. ZnO-NPs and CS-ZnO BNCs were synthesized by a facile co-precipitation method. FE-SEM images revealed that the uniform spherical ZnO-NPs with an average diameter of 35 nm were successfully dispersed on chitosan. MDA-MB-231 MCTSs which were formed in a non-adherent culture plate, possessed functional features of in-vivo tumor. The priority of such culture method to conventionally used 2D monolayer (or parental) cell culture is the mimicking of tumor microenvironment. The toxicity of CS-ZnO BNCs and ZnO-NPs against the MDA-M�231 BCCs was evaluated using MTT-colorimetric assay, which demonstrated superior biocompatibility of CS-ZnO BNCs compared to pure ZnO-NPs (even at high concentration of 100 μg/mL). Survival fraction analysis of cells under clinical X-ray irradiation (6 MV) showed that MCTSs had a higher radioresistance compared to parental cells. Besides, the clonogenic potential of irradiated MCTSs was significantly decreased by the addition of CS-ZnO BNCs similar to that of monolayer cells. The sensitivity enhancement ratios (SER) for MCTSs and monolayer cells were calculated 1.5 and 1.63, respectively. Further, tracking of radiobiological properties and apoptosis induction of MCTSs showed that CS-ZnO BNCs not only could lead to the creation of higher radiation-induced complex DNA break and apoptosis death in MCTSs, but also weakened DNA repair mechanisms. It was found that non-toxic concentration of CS-ZnO BNCs has promising potential to enhance radiosensitivity of resistant-MCTSs as a superior in-vitro tumor model. So, CS-ZnO BNCs can be a prominent candidate for overcoming the resistance of BCCs to radiotherapy. © 2021 Elsevier B.V
On the spectral coherence between two periodically correlated processes
No full textWe introduce a general class of multivariate periodically correlated processes and their corresponding time-domain and spectral-domain characterizations. A spectral coherence based on the Hilbert�Schmidt inner product of the Fourier transforms is introduced to measure the dependence of two periodically correlated (PC) processes. An estimator for the spectral coherence is introduced and studied. A hypothesis on the presence of significant dependence is formulated and the corresponding testing procedure established. Numerical illustrations on the performance of the spectral coherence and its estimator are given using simulated and real PC time series. © 2021 Statistical Society of Canada
Hereditary and non-hereditary pattern of deafness in golestan province, iran
No full textBackground and purpose: Hearing impairment as a heterogeneous disorder is the most common sensory defect. Genetic (hereditary) hearing loss involves 50 of total cases and the remaining 50 are non-hereditary cases caused by unknown causes. This study aimed to investigate the role of consanguineous marriage and the relationship between the type of deafness and the hereditary pattern in families with more than one deaf patient in Golestan province, Iran. Materials and methods: The study population included 165 families with deaf members whose files were available in the General Welfare Department of Golestan Province. They were randomly selected during 2018-2019. Data, including number of family members with hearing loss and severity of the condition were collected by face-to-face interviews with parents. Data analysis was done in SPSS. Results: The mean age of the subjects was 27.67±9.71. Female and male cases included 42.1 and 57.9, respectively. In 85 of the cases, genetic factor and in 15 acquired factors were responsible for hearing loss. Among the genetic causes, 90.9 of the population were autosomal recessive and 9.1 were autosomal dominant. Moreover, 70 of families had consanguineous marriage and first-degree family relationship was seen in 92 families (80). Conclusion: Genetic factor with the autosomal recessive inheritance pattern was the most common cause of hearing loss in the population studied. Increasing awareness about the consequences of consanguineous marriage and genetic counseling are indispensable in decreasing the rate of this condition. © 2021, Mazandaran University of Medical Sciences. All rights reserved
Peaceful coexistence between human and novel coronavirus-2019; where do researchers stand
No full textCOVID-19, as an emerging viral disease, has rapidly become a new pandemic in human life. According to the similarities between novel coronavirus-2019 and Severe acute respiratory syndrome (SARS) virus, the initial assumptions were about the temporary spread of the disease and its rapid control. Nevertheless, increasing human knowledge of the characteristics of the new coronavirus, as well as how the disease has spread, has questioned these assumptions. Currently, it seems that the virus has entered the human life cycle, and individuals should adhere to new lifestyles to return to their normal life. We should select those lifestyles to reduce the risk of contact with the virus and getting COVID-19 as well as to lead a normal life. It is believed that basic medical scientists could play an important role in identifying the most appropriate lifestyles by considering the characteristics of the virus and the desires of different social groups. They could also provide the best answers to the countless questions concerning how to live peacefully, considering the novel COVID-2019. © 2020, Middle East Journal of Rehabilitation and Health Studies. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/) which permits copy and redistribute the material just in noncommercial usages, provided the original work is properly cited
Evaluation of serum alanine aminotransferase and aspartate aminotransferase enzyme levels in women patients with chronic periodontitis
No full textThe authors� aim in this study was to investigate the relationship between chronic periodontitis and liver status using alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in women patients. The researchers conducted a case-control study on women patients referred to Dental School. The researchers collected 5 ml of peripheral venous blood from women for the laboratory process after performing periodontal examination. Participants were 124 women aged 25�50 years (62 cases and 62 control). The difference in serum levels of ALT and the difference in serum levels of AST between the two groups were not statistically significant. However, there was a significant correlation between liver enzymes and periodontitis parameters. © 2021 Taylor & Francis Group, LLC
The effect of price on cigarette consumption, distribution, and sale in Tehran: a qualitative study
No full textBackground: Appropriate increases in tobacco taxes and prices are an essential component of comprehensive tobacco control strategies. This study investigates factors related to the use, sale, and distribution of cigarettes in Iran, focusing on the relationship between cigarette price and its consumption. Methods: This interview-based qualitative study was conducted among 20 participants, including cigarette smokers, retail shop owners, large-scale distributors, and an expert in tobacco control research. Results: Seven themes were extracted from participant interviews, including the type and price of cigarette, the best time to sell cigarettes, profits from the sale of cigarette, affordability, rise in cigarette price and smokers� reaction to it, lobbying and black-market sales of cigarettes, and the sale and distribution of cigarettes across the country. Although the price of cigarettes in Iran has shown some increases in the past decade, the timing of these increases are not predictable and the limited amount of these increases has not reduced the use of cigarettes. Following a price increase, consumers are more likely to switch from buying packets to single cigarettes, or buy a less expensive brand, then to quit. Moreover, increases in prices may encourage smokers and sellers to buy a large number of cigarettes and store them for a rainy day. Another adverse effect may be increased smuggling of illicit cigarettes to balance the pressure caused by rising prices. Conclusions: Our findings highlight two important aspects concerning cigarette pricing in Iran. First is the change in the type of purchase from the whole box of cigarettes to the single stick cigarette or swapping to less expensive cigarettes. Second, increase in cigarette price (either through taxing or regular increases) could be offset by flooding smuggled cigarettes into the market. Therefore, in addition to raising cigarette prices, reducing cigarette consumption rates in Iran requires the development and effective implementation of regulatory policies to control cigarette smuggling, reduce purchasing, and subsequently curb the use of this leading cause of premature morbidity and mortality. © 2021, The Author(s)
Assessment of bone mineral density in patients undergoing hemodialysis; An Iranian population-based study
No full textBackground: End-stage renal disease (ESRD) is a condition in which bone turnover and metabolism is impaired; thus, osteoporosis and low bone density are subsequently inevitable. We aimed to determine bone mineral density (BMD) and biochemical markers, and associated factors in hemodialysis (HD) patients. Methods: Patients aged 30-70 years undergoing HD between 2015 to 2019 were enrolled in this cross-sectional study. BMD measured by dual energy x-ray absorptiometry (DEXA) and biochemical laboratory tests were assessed in 200 patients undergoing HD. Statistical analysis was based on t test, Pearson, regression and Mann-Whitney tests using SPSS 16. Results: Two hundred patients were investigated. Sixty percent of the patients were female. Mean ± SD of participants' age was 58.6 (±11.63) years and mean ± SD for duration of HD was 45.69 (± 43.76) months. Osteoporosis was found in 48 (n = 96) and low bone density in 36 (n = 76) of our patients. General osteoporosis was more frequent in those undergoing HD for more than 3 years, although not significantly (P = 0.093, odds ratio OR = 0.37). However, regional osteoporosis in hip and femoral neck, but not spine vertebrae, were significantly higher after three years of HD (P = 0.036, OR = 0.27; P = 0.042, OR = 0.27; and P = 0.344, OR = 0.56, respectively). Increased body mass index (BMI) correlated negatively with osteoporosis (P = 0.050). Conclusion: With increasing age and duration of HD, BMD decreases. Higher BMI was associated with higher bone mass density. Bone density assessment seems to be necessary in patients undergoing HD. © 2021 Academy of Medical Sciences of I.R. Iran. All rights reserved
Spatial, temporal, and demographic patterns in prevalence of chewing tobacco use in 204 countries and territories, 1990�2019: a systematic analysis from the Global Burden of Disease Study 2019
No full textBackground: Chewing tobacco and other types of smokeless tobacco use have had less attention from the global health community than smoked tobacco use. However, the practice is popular in many parts of the world and has been linked to several adverse health outcomes. Understanding trends in prevalence with age, over time, and by location and sex is important for policy setting and in relation to monitoring and assessing commitment to the WHO Framework Convention on Tobacco Control. Methods: We estimated prevalence of chewing tobacco use as part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2019 using a modelling strategy that used information on multiple types of smokeless tobacco products. We generated a time series of prevalence of chewing tobacco use among individuals aged 15 years and older from 1990 to 2019 in 204 countries and territories, including age-sex specific estimates. We also compared these trends to those of smoked tobacco over the same time period. Findings: In 2019, 273·9 million (95 uncertainty interval 258·5 to 290·9) people aged 15 years and older used chewing tobacco, and the global age-standardised prevalence of chewing tobacco use was 4·72 (4·46 to 5·01). 228·2 million (213·6 to 244·7; 83·29 82·15 to 84·42) chewing tobacco users lived in the south Asia region. Prevalence among young people aged 15�19 years was over 10% in seven locations in 2019. Although global age-standardised prevalence of smoking tobacco use decreased significantly between 1990 and 2019 (annualised rate of change: �1·21% �1·26 to �1·16), similar progress was not observed for chewing tobacco (0·46% 0·13 to 0·79). Among the 12 highest prevalence countries (Bangladesh, Bhutan, Cambodia, India, Madagascar, Marshall Islands, Myanmar, Nepal, Pakistan, Palau, Sri Lanka, and Yemen), only Yemen had a significant decrease in the prevalence of chewing tobacco use, which was among males between 1990 and 2019 (�0·94% �1·72 to �0·14), compared with nine of 12 countries that had significant decreases in the prevalence of smoking tobacco. Among females, none of these 12 countries had significant decreases in prevalence of chewing tobacco use, whereas seven of 12 countries had a significant decrease in the prevalence of tobacco smoking use for the period. Interpretation: Chewing tobacco remains a substantial public health problem in several regions of the world, and predominantly in south Asia. We found little change in the prevalence of chewing tobacco use between 1990 and 2019, and that control efforts have had much larger effects on the prevalence of smoking tobacco use than on chewing tobacco use in some countries. Mitigating the health effects of chewing tobacco requires stronger regulations and policies that specifically target use of chewing tobacco, especially in countries with high prevalence. Funding: Bloomberg Philanthropies and the Bill & Melinda Gates Foundation. © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens