60 research outputs found

    Development of a novel hyperbranched unsaturated polyester resin: Synthesis, characterization, and potential applications in car body putty

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    This work presents a comprehensive synthesis method for the development of a new hyperbranched unsaturated polyester resin (HUPR). The resin is synthesized by modifying dehydrated castor oil fatty acid (DCOFA) with methyl methacrylate (MMA) and styrene, dicyclopentadiene-maleate (DCPD-M), and trimethylol propane diallyl ether (TMPDE). The synthesis process involves the radical addition reaction of DCOFA with MMA and styrene, followed by the addition of DCPD-M and TMPDE to form a HUPR. The resulting resin exhibits enhanced properties, making it a promising candidate for car body putty in the polymer industry

    Clinical Characteristics of Fatal Cases of COVID-19 in Tabriz, Iran: An Analysis of 111 Patients

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    Introduction: The rapid worldwide spread, in addition to the morbidity and mortality associated with the novel coronavirus disease 2019 (COVID-19), have raised concern throughout the world. Identifying the characteristics of patients who died of COVID-19 is essential to implement preventive measures. Objective: We aimed at investigating these characteristics among the Iranian population in Tabriz. Methods: In this case series, we analyzed clinical characteristics, laboratory parameters, and imaging findings of 111 patients with a reverse transcriptase-polymerase chain reaction (RT-PCR)-confirmed COVID-19 diagnosis who died during hospitalization. The studied patients had been admitted to the hospital between February 2020 and May 2020. Results: The median age of patients was 73 years (IQR, 62-82 years) and approximately 70% of them were male. The median oxygen saturation on admission was 88% (IQR, 80-92%) and dyspnea, cough, and fever were the most common presenting symptoms. Among comorbidities, diabetes, hypertension, and cardiovascular diseases were more frequently observed among patients who had a fatal outcome. While ground-glass opacity was the most commonly reported finding on chest computed tomography, 5% of the patients had no abnormal finding on imaging. Chloroquine was the most frequently used medication for treatment. Conclusion: Our results showed that the majority of COVID-19 deaths occurred in male elderly with decreased levels of oxygen saturation and elevated levels of lactate dehydrogenase and erythrocyte sedimentation rate on admission

    Efficacy of levamisole with standard care treatment vs. standard care in clinical presentations of non-hospitalized patients with COVID-19: a randomized clinical trial

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    Objective: The aim of this study was to evaluate the influence of adding a 10-day course of levamisole (LVM) to the standard care compared with standard care alone, on the clinical status of COVID-19 patients with mild to moderate disease. Methods:  In this randomized open-label trial, we enrolled non-hospitalized patients with mild to moderate COVID-19 at nine health centers in Tehran province, Iran, in 2021. Patients were randomly assigned to receive a 10-day course of LVM with standard care (n=185) or standard care alone (n=180) in a 1:1 ratio. On days 1 to 10, LVM was administered orally at a dosage of 50 mg. The participants were called and followed on days 1, 3, 5, 7, 9, and 14. The measured parameters were general health condition, hospitalization rate, signs and symptoms, and adverse events. The generalized estimating equations model was used for analysis. Results: Among 507 randomized patients, 473 patients started the experiment and received LVM plus standard care or received the standard care alone; 385 patients included in the analysis; 346 (98%) patients completed the trial. The median age of the patients was 40 years [IQR: 32-50.75]; and ‎201 (55.1%)‎ patiens were male. The mean age, sex ratio, and frequency of the underlying diseases of the patients in the two study groups had no ‎statistically significant differences (P>0.05). Compared to the control group, LVM improved the general health condition of the patients (B=-0.635; 95% CI: -0.041,-0.329; P<0.001). Patients receiving LVM compared with standard care group had significantly lower odds of developing fever (OR=0.260; 95% CI: 0.11‎‎3‎,0.59‎‎9‎; P=0.002), chills (OR=0.223; 95% CI:‎‎ 0.07‎‎6,‎0.64‎‎8‎; P= 0.006), fatigue (OR=0.576; 95% CI:‎ 0.34‎‎6,‎0.96‎‎0‎‎; P=0.034), and myalgia (OR=0.54‎‎4‎; 95% CI:‎ 0.31‎‎7‎,0.93‎‎2‎‎; P=0.027). No significant difference was observed in the rate of hospitalization. Although the intervention group had greater adverse effects than the control group, the difference was not statistically significant. Conclusion: Findings of this study suggest that LVM has clinical benefits in improving patients’ health condition with mild to moderate COVID-19

    The global burden of adolescent and young adult cancer in 2019 : a systematic analysis for the Global Burden of Disease Study 2019

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    Background In estimating the global burden of cancer, adolescents and young adults with cancer are often overlooked, despite being a distinct subgroup with unique epidemiology, clinical care needs, and societal impact. Comprehensive estimates of the global cancer burden in adolescents and young adults (aged 15-39 years) are lacking. To address this gap, we analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, with a focus on the outcome of disability-adjusted life-years (DALYs), to inform global cancer control measures in adolescents and young adults. Methods Using the GBD 2019 methodology, international mortality data were collected from vital registration systems, verbal autopsies, and population-based cancer registry inputs modelled with mortality-to-incidence ratios (MIRs). Incidence was computed with mortality estimates and corresponding MIRs. Prevalence estimates were calculated using modelled survival and multiplied by disability weights to obtain years lived with disability (YLDs). Years of life lost (YLLs) were calculated as age-specific cancer deaths multiplied by the standard life expectancy at the age of death. The main outcome was DALYs (the sum of YLLs and YLDs). Estimates were presented globally and by Socio-demographic Index (SDI) quintiles (countries ranked and divided into five equal SDI groups), and all estimates were presented with corresponding 95% uncertainty intervals (UIs). For this analysis, we used the age range of 15-39 years to define adolescents and young adults. Findings There were 1.19 million (95% UI 1.11-1.28) incident cancer cases and 396 000 (370 000-425 000) deaths due to cancer among people aged 15-39 years worldwide in 2019. The highest age-standardised incidence rates occurred in high SDI (59.6 [54.5-65.7] per 100 000 person-years) and high-middle SDI countries (53.2 [48.8-57.9] per 100 000 person-years), while the highest age-standardised mortality rates were in low-middle SDI (14.2 [12.9-15.6] per 100 000 person-years) and middle SDI (13.6 [12.6-14.8] per 100 000 person-years) countries. In 2019, adolescent and young adult cancers contributed 23.5 million (21.9-25.2) DALYs to the global burden of disease, of which 2.7% (1.9-3.6) came from YLDs and 97.3% (96.4-98.1) from YLLs. Cancer was the fourth leading cause of death and tenth leading cause of DALYs in adolescents and young adults globally. Interpretation Adolescent and young adult cancers contributed substantially to the overall adolescent and young adult disease burden globally in 2019. These results provide new insights into the distribution and magnitude of the adolescent and young adult cancer burden around the world. With notable differences observed across SDI settings, these estimates can inform global and country-level cancer control efforts. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe

    Changes in preterm birth and stillbirth during COVID-19 lockdowns in 26 countries.

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    Preterm birth (PTB) is the leading cause of infant mortality worldwide. Changes in PTB rates, ranging from -90% to +30%, were reported in many countries following early COVID-19 pandemic response measures ('lockdowns'). It is unclear whether this variation reflects real differences in lockdown impacts, or perhaps differences in stillbirth rates and/or study designs. Here we present interrupted time series and meta-analyses using harmonized data from 52 million births in 26 countries, 18 of which had representative population-based data, with overall PTB rates ranging from 6% to 12% and stillbirth ranging from 2.5 to 10.5 per 1,000 births. We show small reductions in PTB in the first (odds ratio 0.96, 95% confidence interval 0.95-0.98, P value <0.0001), second (0.96, 0.92-0.99, 0.03) and third (0.97, 0.94-1.00, 0.09) months of lockdown, but not in the fourth month of lockdown (0.99, 0.96-1.01, 0.34), although there were some between-country differences after the first month. For high-income countries in this study, we did not observe an association between lockdown and stillbirths in the second (1.00, 0.88-1.14, 0.98), third (0.99, 0.88-1.12, 0.89) and fourth (1.01, 0.87-1.18, 0.86) months of lockdown, although we have imprecise estimates due to stillbirths being a relatively rare event. We did, however, find evidence of increased risk of stillbirth in the first month of lockdown in high-income countries (1.14, 1.02-1.29, 0.02) and, in Brazil, we found evidence for an association between lockdown and stillbirth in the second (1.09, 1.03-1.15, 0.002), third (1.10, 1.03-1.17, 0.003) and fourth (1.12, 1.05-1.19, <0.001) months of lockdown. With an estimated 14.8 million PTB annually worldwide, the modest reductions observed during early pandemic lockdowns translate into large numbers of PTB averted globally and warrant further research into causal pathways

    Changes in preterm birth and stillbirth during COVID-19 lockdowns in 26 countries.

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    Preterm birth (PTB) is the leading cause of infant mortality worldwide. Changes in PTB rates, ranging from -90% to +30%, were reported in many countries following early COVID-19 pandemic response measures ('lockdowns'). It is unclear whether this variation reflects real differences in lockdown impacts, or perhaps differences in stillbirth rates and/or study designs. Here we present interrupted time series and meta-analyses using harmonized data from 52 million births in 26 countries, 18 of which had representative population-based data, with overall PTB rates ranging from 6% to 12% and stillbirth ranging from 2.5 to 10.5 per 1,000 births. We show small reductions in PTB in the first (odds ratio 0.96, 95% confidence interval 0.95-0.98, P value <0.0001), second (0.96, 0.92-0.99, 0.03) and third (0.97, 0.94-1.00, 0.09) months of lockdown, but not in the fourth month of lockdown (0.99, 0.96-1.01, 0.34), although there were some between-country differences after the first month. For high-income countries in this study, we did not observe an association between lockdown and stillbirths in the second (1.00, 0.88-1.14, 0.98), third (0.99, 0.88-1.12, 0.89) and fourth (1.01, 0.87-1.18, 0.86) months of lockdown, although we have imprecise estimates due to stillbirths being a relatively rare event. We did, however, find evidence of increased risk of stillbirth in the first month of lockdown in high-income countries (1.14, 1.02-1.29, 0.02) and, in Brazil, we found evidence for an association between lockdown and stillbirth in the second (1.09, 1.03-1.15, 0.002), third (1.10, 1.03-1.17, 0.003) and fourth (1.12, 1.05-1.19, <0.001) months of lockdown. With an estimated 14.8 million PTB annually worldwide, the modest reductions observed during early pandemic lockdowns translate into large numbers of PTB averted globally and warrant further research into causal pathways

    Ultrasound-promoted synthesis of (4 or 5)-aryl-2-aryloyl-(1H)-imidazoles in water

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    A green and efficient method for the synthesis of (4 or 5)-aryl-2-aryloyl-(1H)-imidazoles via self-condensation reaction of arylglyoxal hydrates in the presence of ammonium acetate using water as solvent under ultrasonic irradiation was reported. The reactions proceeded in high yields and very short reaction time. Introduced procedure is completely ecofriendly and don’t need any toxic organic solvent in all performing steps. In addition we use computational chemistry for acquiring some information about the thermochemistry and geometrical structure of these imidazole derivatives

    Theoretical calculations of the relative pKa values of some selected aromatic arsonic acids in water using density functional theory

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    With the focus on calculating the equilibrium constant (Ka) of arsonic acids (RAsO(OH)2) in aqueous media, the behavior of both neutral and negatively charged species of some arsonic acids have been considered through the isodesmic reaction scheme with polarized continuum model of solvation. The relative pKa values of a number of arsonic acids were calculated using density functional theory (DFT), with methylarsonic acid (CH3AsO(OH)2) used as a reference molecule. Various basis sets such as (6-31G(d), 6-31+G(d), 6-311++G(d,p) and 6-311++G(2d,2p)) in conjunction with B3LYP computational method were examined. Finally the latter one was found to give better results. The results of applied B3LYP 6-311++G(2d,2p) method for pKa values of 25 arsonic acids in aqueous media showed good agreement with corresponding experimental pKa values. In this level of theory the average error was less than 0.3 pKa units. The type of substituent affected the acid strength, with electron withdrawing substituents lowering the pKa and electron releasing groups increasing it
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