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941.
Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver‐related morbidity; its prevalence is elevating due to the rising epidemic of obesity. Several clinical trials have examined the effects of curcumin supplementation on anthropometric variables in NAFLD patients with inconclusive results. This dose–response meta‐analysis aimed to evaluate the impact of curcumin supplementation on body mass index (BMI), body weight, and waist circumference (WC) in patients with NAFLD. A systematic review of the literature was conducted using PubMed/Medline, ISI Web of Science, Scopus, Cochrane Library, EMBASE, Google Scholar, Sid.ir, and Magiran.com to identify eligible studies up to March 2019. A meta‐analysis of eligible studies was performed using the random‐effects model to estimate the pooled effect size. Eight randomized controlled trials with 520 participants (curcumin group = 265 and placebo group = 255) were included. Supplementation dose and duration ranged from 70 to 3,000 mg/day and 8 to 12 weeks, respectively. Curcumin supplementation significantly reduced BMI (weighted mean difference [WMD] = ?0.34 kg/m2, 95% CI [?0.64, ?0.04], p < .05) and WC (WMD = ?2.12 cm, 95% CI [?3.26, ?0.98], p < .001). However, no significant effects of curcumin supplementation on body weight were found. These results suggest that curcumin supplementation might have a positive effect on visceral fat and abdominal obesity that have been associated with NAFLD.  相似文献   
942.
目的:分析2009-2016年间伊朗传统医学使用及家庭费用支出情况的影响因素.方法:基于伊朗家庭收入和支出调查(HIES),采用伪面板数据的Tobit模型分析家庭收入、家庭财富等级、家庭规模、男性数量、识字成员数量、家庭成员平均年龄对传统医学使用及经费支出的影响.结果:研究结果表明,越富裕的家庭使用传统医学的频率越高;...  相似文献   
943.
Objectives:To utilize our tertiary center’s experience with Temporal lobe epilepsy (TLE) and Temporal plus epilepsy (TPE) cases and determine whether a correlation exists between ictal semiology signs, their localization/lateralization value after intracranial electroencephalography (EEG) monitoring, and surgical outcomes.Methods:A retrospective study was conducted among epilepsy patients who underwent resective surgery for TLE or TPE after intracranial EEG monitoring between January 2008 and December 2018 at King Faisal Specialist Hospital in Riyadh, Saudi Arabia. Data were retrieved for 464 patients; 181 had intracranial electrode monitoring.Results:Forty-eight patients with a mean age of 27 years (SD=8.4) were included; 15 patients had TPE. Auras were frequently reported, emotional auras, in the form of fear (35%). The localization/lateralization value of aura was statistically significant for TPE patients, including visual hallucinations and vertigo, lateralized to the left and right temporo-occipital, respectively (p=0.009 and <0.001). Early-onset ictal manual automatism, oral automatism, late-onset dystonic posture, and late head-turning were significant for TLE without significant lateralization value. The ictal onset zone’s localization was significant between the scalp and intracranial EEG findings in mesial TLE patients. The probability of seizure freedom (Engel class I) was 74%, 60%, and 67% at 2-year follow-up for mesial, lateral TLE, and TPE, respectively.Conclusion:Our results are consistent with previous studies and confirm the importance of ictal semiology signs in TLE and TPE. The addition of intracranial EEG monitoring in these cases helped improve the surgical outcomes.

Epilepsy is one of the most common neurological disorders, affecting approximately 70 million people globally.1 Thirty percent of these patients have drug-resistant epilepsy,2 and most cases referred for epilepsy surgery involve temporal lobe epilepsy (TLE).3 However, after standard temporal lobectomy, around 40% of these patients will experience recurrent seizures.4 A variety of explanations have been proposed for these surgical failures, including incomplete removal of the epileptogenic zone, additional contralateral focus (bilateral TLE), dual pathology (mesial and neocortical), and extended epileptogenic focus to the neighboring structures, including extratemporal or temporal plus epilepsy (TPE).5The TPE is defined as focal epilepsy with a complex epileptogenic network involving the temporal lobe and the surrounding areas, such as the orbitofrontal cortex, insula, operculum, and temporo-parieto-occipital junction.6 A thorough presurgical evaluation is required to delineate the epileptogenic zone for successful resective surgery. In phase I assessment, scalp video electroencephalography (EEG) monitoring, brain magnetic resonance imaging (MRI), and neuropsychological evaluation are needed. Further non-invasive investigations can be included if the initial results are discordant. To reach a well-demarcated epileptogenic focus requires intracranial monitoring, including the subdural grid, strips, and depth, which is known as phase II assessment.7 Seizure semiology is the first step in a presurgical evaluation, and ictal semiology and scalp-EEG results play a valuable role in distinguishing TLE from TPE.8 Patients with TLE are more likely to experience abdominal auras, ictal gestural automatism, and post-ictal amnesia. However, TPE patients are more likely to experience gustatory hallucinations, rotatory vertigo, auditory illusions, contralateral eye and head versions, piloerection, and ipsilateral tonic posturing. Similar findings were highlighted in a review of TPE cases.4 Furthermore, laryngeal and throat constriction and the atypical distribution of somatosensory symptoms at seizure onset have been found.4Although some studies have found a correlation between seizure semiology and intracranial EEG monitoring in TLE (mesial vs. lateral) vs. TPE, none evaluated lateralization values. This study aims to utilize our tertiary center’s experience with TLE and TPE cases and determine whether a correlation exists between ictal semiology signs, their localization/lateralization value after intracranial electroencephalography (EEG) monitoring and surgical outcomes. We also highlight the process of phase I presurgical assessment (including ictal/interictal scalp EEG, MRI, positron emission tomography [PET], and neuropsychology) in our center.  相似文献   
944.
BackgroundIn February 2020, the Ministry of Health and Medical Education in Iran announced the first case of COVID-19. The aim of this study was to investigate the impact of COVID-19 on the number of CT-Scans and MRI services in public hospitals in western Iran.MethodsWe collected CT-scans and MRI services data from 18 public hospitals via Vice-Chancellor Office, Lorestan University of Medical Sciences from January 2017 to February 2021. Interrupted time series analysis (ITSA) was conducted to assess the impact of COVID-19 on CT-Scans and MRI services. More specifically, ITSA was conducted using ordinary least squares regression with the number of CT-Scans and MRI services per 1,000 registered persons per month as dependent variable.ResultsAt the beginning of the observation period, the monthly rate of CT-Scans was constant (p for trend = 0.267) at 291.9 (from 95%CI 240.5 to 343.4) per 1,000 registered patients. The first case of COVID-19 coincided with an abrupt increase by 211.8 (from 95%CI 102.9 to 320.7) per 1,000 patients. Thereafter, the trend of CT-Scans did not change (p=0.576) compared to the pre-pandemic period. The rate of MRI services was 363.5 per 1,000 per registered patients per month (P = <0.0001) with a slightly decreasing trend (coefficient=-5; 95%CI, -6.9 to -3.1).ConclusionThe findings of this study showed that crises such as COVID-19 can affect the service delivery process. Health policymakers and decision makers should work to prevent potential reductions in health care during events such as COVID-19.  相似文献   
945.
The present research utilized a simplified procedure for developing a novel electro-chemical DNA biosensor based on a carbon paste electrode (CPE) modified with three-dimensional (3D) cubic Eu3+/Cu2O nanostructures with clover-like faces (Eu3+/Cu2O CLFNs). The modified electrode was applied to monitor electro-chemical interactions between dsDNA and cytarabine for the first time. Then, the decreased oxidation signal of guanine following the interactions between cytarabine and dsDNA was utilized as an indicator for selectively determining cytarabine using differential pulse voltammetry (DPV). According to the findings, the oxidation peak current of guanine was linearly proportionate with the cytarabine concentration in the range between 0.01 and 90 μM. Additionally, the limit of quantification (LOQ) and the limit of detection (LOD) respectively equaled 9.4 nM and 2.8 nM. In addition, the repeatability, applicability and reproducibility of this analysis to drug dosage forms and human serum samples were investigated. Furthermore, UV-vis spectroscopy, DPV, docking and viscosity measurements were applied to elucidate the interaction mechanism of dsDNA with cytarabine. It was found that this DNA biosensor may be utilized to sensitively, accurately and rapidly determine cytarabine.

Electrochemical biosensor based on three-dimensional (3D) cubic of Eu3+/Cu2O with clover-like face nano-structures and ds-DNA modified carbon paste electrode for detecting cytarabine was fabricated.  相似文献   
946.
Given the important aspects of wound healing approaches, in this work, an innovative biocompatible nanobiocomposite scaffold was designed and prepared based on cross-linked lignin–agarose hydrogel, extracted silk fibroin solution, and zinc chromite (ZnCr2O4) nanoparticles. Considering the cell viability technique, red blood cell hemolysis in addition to anti-biofilm assays, it was determined that after three days, the toxicity of the cross-linked lignin–agarose/SF/ZnCr2O4 nanobiocomposite was less than 13%. Moreover, the small hemolytic effect (1.67%) and high level of prevention in forming a P. aeruginosa biofilm with low OD value (0.18) showed signs of considerable hemocompatibility and antibacterial activity. Besides, according to an in vivo assay study, the wounds of mice treated with the cross-linked lignin–agarose/SF/ZnCr2O4 nanobiocomposite scaffold were almost completely healed in five days. Aside from these biological tests, the structural features were evaluated by FT-IR, EDX, FE-SEM, and TG analyses, as well as swelling ratio, rheological, and compressive mechanical study tests. Additionally, it was concluded that adding silk fibroin and ZnCr2O4 nanoparticles could enhance the mechanical tensile properties of cross-linked lignin–agarose hydrogel, and also an elastic network was characterized for this designed nanobiocomposite.

Given the important aspects of wound healing approaches, in this work, an innovative biocompatible nanobiocomposite scaffold was designed and prepared based on cross-linked lignin–agarose hydrogel, extracted silk fibroin solution, and zinc chromite (ZnCr2O4) nanoparticles.  相似文献   
947.
The emerging variants of SARS coronavirus-2 (SARS-CoV-2) have been continuously spreading all over the world and have raised global health concerns. The B.1.1.7 (United Kingdom), P.1 (Brazil), B.1.351 (South Africa) and B.1.617 (India) variants, resulting from multiple mutations in the spike glycoprotein (SGp), are resistant to neutralizing antibodies and enable increased transmission. Hence, new drugs might be of great importance against the novel variants of SARS-CoV-2. The SGp and main protease (Mpro) of SARS-CoV-2 are important targets for designing and developing antiviral compounds for new drug discovery. In this study, we selected seventeen phytochemicals and later performed molecular docking to determine the binding interactions of the compounds with the two receptors and calculated several drug-likeliness properties for each compound. Luteolin, myricetin and quercetin demonstrated higher affinity for both the proteins and interacted efficiently. To obtain compounds with better properties, we designed three analogues from these compounds and showed their greater druggable properties compared to the parent compounds. Furthermore, we found that the analogues bind to the residues of both proteins, including the recently identified novel variants of SARS-CoV-2. The binding study was further verified by molecular dynamics (MD) simulation and molecular mechanics/Poisson Boltzmann surface area (MM/PBSA) approaches by assessing the stability of the complexes. MD simulations revealed that Arg457 of SGp and Met49 of Mpro are the most important residues that interacted with the designed inhibitors. Our analysis may provide some breakthroughs to develop new therapeutics to treat the proliferation of SARS-CoV-2 in vitro and in vivo.

Three designed inhibitors with potential inhibition efficacy against the emerging variants of SARS coronavirus-2 (SARS-CoV-2).  相似文献   
948.
The coexistence of semiconducting (2H) and metallic (1T) phases of MoS2 monolayers has further pushed their strong potential for applications in the next generation of electronic devices based on two-dimensional lateral heterojunctions. Structural defects have considerable effects on the properties of these 2D devices. In particular, the interfaces of two phases are often imperfect and may contain numerous vacancies created by phase engineering techniques, e.g. under an electron beam. Here, the transport behaviors of the heterojunctions with the existence of point defects are explored by means of first-principles calculations and non-equilibrium Green''s function approach. While vacancies in semiconducting MoS2 act as scattering centers, their presence at the interface improves the flow of the charge carriers. In the case of VMo, the current has been increased by two orders of magnitude in comparison to the perfect device. The enhancement of transmission was explained by changes in the electronic densities at the T–H interface, which open new transport channels for electron conduction.

Our systematic study shows significant improvement in transport properties of MoS2-based lateral T–H heterophase junctions when interfacial defects are present.

Among the developing family of two-dimensional (2D) materials, transition metal dichalcogenides (TMDs) provide some of the most diverse electronic properties including acting as topological insulators, semiconductors, (semi)metals and superconductors.1–3 Noticeably, such a difference in the electronic structure of TMDs correlates with their structural configurations, called phases.4 Monolayers of MoS2 in the H-phase, with trigonal prismatic coordination of metal atoms, is a semiconducting material,5,6 while T-phase with octahedral coordination shows metallic character. The H-phase monolayer is reported to be a promising material for field-effect transistors (FETs) with small-scale channel lengths and negligible current leakage.5,6Recent experiments have already shown controlled transitions from one phase to another via external stimuli such as electron beam,7 ion intercalation,8 or laser irradiation.9 These phase-engineered 2D materials with minimum variations in atomic structure and uniform stoichiometry not only demonstrate rich physical behavior but also open up new avenues for the design of electronic devices. The fabrication of lateral metallic/semiconducting heterostructures has been suggested as a practical method to minimize the contact resistance at the interface between 2D semiconductors and metal electrodes. In particular, the formation of covalent bonds between the two phases can introduce paths for carriers to travel across the interfaces, thus, the Schottky barrier and contact resistance are reduced.10–13 It has also been demonstrated that 1T-phase engineered electrodes in MoS2 based electronic devices would generate ohmic contacts and, as a result, improve electrical characteristics.12,14Apart from intrinsic defects, the local phase transitions induced by electron beam irradiation may give rise to the formation of point defects, in particular at the interface of the two phases.15–22 Defects can also be intentionally introduced during the post-growth stage via ion bombardment, plasma treatment, vacuum annealing, or chemical etching.15–22 Indeed, theoretical and experimental results showed that the presence of sulfur vacancies can decrease the energy difference between the H and T phases and eventually stabilize the 1T phase in MoS2 monolayer.23,24 The presence of point defects in semiconducting MoS2 monolayers leads to the observation of the localized states in their electronic structure, which act as short-ranged scattering centers for charge carriers.25–28 Hence, defects were found to deteriorate the mobility of the fabricated devices.29–31 It was also shown that sulfur line vacancies in MoS2 can behave like pseudo-ballistic wire for electron transport.32So far, several theoretical studies have reported the transport properties of phase-engineered devices based on TMDs monolayers including MoS2 based lateral junctions.11,12,33–35,35–37 In most of these studies, however, it is assumed that two phases have a perfect crystalline structure and connected via an atomically sharp and defect-free interface.Here, transport properties of devices based on MLs MoS2, containing various point vacancies and antisites at the interface between metallic and semiconducting phases, are the subject of the present study. Our systematic investigations show significant improvements in the current, as molybdenum vacancy and vacancy complexes are created at the interfaces of two phases. These findings render defect engineering as an efficient route to further improve the performance of the devices based on the lateral heterojunctions formed from TMDs.  相似文献   
949.
Coronavirus disease-19 (COVID-19) caused by SARS-CoV-2 has already killed more than one million people worldwide. Since novel coronavirus is a new virus, mining its genome sequence is of crucial importance for drug/vaccine(s) development. Whole genome sequencing is a helpful tool in identifying genetic changes that occur in a virus when it spreads through the population. In this study, we performed complete genome sequencing of SARS-CoV-2 to unveil the genomic variation and indel, if present. We discovered thirteen (13) mutations in Orf1ab, S and N gene where seven (7) of them turned out to be novel mutations from our sequenced isolate. Besides, we found one (1) insertion and seven (7) deletions from the indel analysis among the 323 Bangladeshi isolates. However, the indel did not show any effect on proteins. Our energy minimization analysis showed both stabilizing and destabilizing impact on viral proteins depending on the mutation. Interestingly, all the variants were located in the binding site of the proteins. Furthermore, drug binding analysis revealed marked difference in interacting residues in mutants when compared to the wild type. Our analysis also suggested that eleven (11) mutations could exert damaging effects on their corresponding protein structures.

SARS-CoV-2 mutational impact analysis.  相似文献   
950.
Four new series of chalcones containing imidazole bromonium and benzimidazole bromonium salts with spacer alkyl chains (Cn, n = 2 and 4) were synthesized and the chemical structure, thermal behavior, photoluminescence and gas sensing were characterized by several technical methods. The studies have indicated similar mesomorphic properties of the synthesized compounds, dependent on the terminal alkyl-chain and lengths of the alkoxy-spacer. Almost compounds with shorter alky chains, 4a–4e, 5a–5c, 6a–6c and 7a–7d, did not show liquid crystal properties, while the results of other compounds confirm the existence of smectic A in cooling and heating cycles. Photoluminescence of compounds 5a–5i and 7a–7i was also studied. The emission in the blue region reveals that the material has blue light emission properties. Sensing behavior of compounds 4i and 5i was investigated for NH3 and NO2 gases. The sensors exhibited high sensitivity toward NH3, while sensitivity toward the oxidizing gas NO2 is lower.

Four new series of chalcones containing imidazole bromonium and benzimidazole bromonium salts with spacer alkyl chains (Cn, n = 2 and 4) were synthesized and their chemical structure, thermal behavior, photoluminescence and gas sensing ability were characterized.  相似文献   
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