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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Mahmoud A. El Hassab Tamer M. Ibrahim Aly A. Shoun Sara T. Al-Rashood Hamad M. Alkahtani Amal Alharbi Razan O. Eskandrani Wagdy M. Eldehna 《RSC advances》2021,11(26):16026
In the present era, there are many efforts trying to face the emerging and successive waves of the COVID-19 pandemic. This has led to considering new and unusual targets for SARS CoV-2. 2′-O-Methyltransferase (nsp16) is a key and attractive target in the SARS CoV-2 life cycle since it is responsible for the viral RNA protection via a cap formation process. In this study, we propose a new potential inhibitor for SARS COV-2 2′-O-methyltransferase (nsp16). A fragment library was screened against the co-crystal structure of the SARS COV-2 2′-O-methyltransferase complexed with Sinefungin (nsp16 – PDB ID: 6WKQ), and consequently the best proposed fragments were linked via a de novo approach to build molecule AP-20. Molecule AP-20 displayed a superior docking score to Sinefungin and reproduced the key interactions in the binding site of 2′-O-methyltransferase. Three molecular dynamic simulations of the 2′-O-methyltransferase apo structure and its complexed forms with AP-20 and Sinefungin were performed for 150 nano-seconds to provide insights on the dynamic nature of such setups and to assess the stability of the proposed AP-20/enzyme complex. AP-20/enzyme complex demonstrated better stability for the ligand–enzyme complex compared to Sinefungin in a respective setup. Furthermore, MM-PBSA binding free energy calculations showed a better profile for AP-20/enzyme complex compared to Sinefungin/enzyme complex emphasizing the potential inhibitory effect of AP-20 on SARS COV-2 2′-O-methyltransferase. We endorse our designed molecule AP-20 to be further explored via experimental evaluations to confront the spread of the emerging COVID-19. Also, in silico ADME profiling has ascribed to AP-20 an excellent safety and metabolic stability profile.The identification of AP-20 as a potential SARS COV-2 2′-O-methyltransferase inhibitor: fragment-based screening approach and MM-PBSA calculations. 相似文献
982.
Juan Carlos LpezRodríguez Juan RodríguezCoira Sara Bened Coral Barbas Domingo Barber María Teresa Villalba María Marta Escribese Alma Villaseor Eva Batanero 《Clinical and translational allergy》2021,11(7)
BackgroundSeveral studies have shown a correlation between an altered metabolome and respiratory allergies. The epithelial barrier hypothesis proposes that an epithelial barrier dysfunction can result in allergic diseases development. Der p 1 allergen from house dust mite is a renowned epithelial barrier disruptor and allergy initiator due to its cysteine‐protease activity. Here, we compared the metabolic profile of the bronchial epithelium exposed or not to Der p 1 during barrier establishment to understand its active role in allergy development.MethodsCalu‐3 cells were cultivated in air‐liquid interface cultures and exposed to either Der p 1 or Ole e 1 allergens during barrier establishment. The comparative metabolomics analysis of apical and basolateral media were performed using liquid chromatography and capillary electrophoresis both coupled to mass spectrometry.ResultsWe showed that epithelial barrier disruption by Der p 1 was associated with a specific metabolic profile, which was highly dependent on the state of the epithelium at the time of contact. Moreover, an apical‐basolateral distribution of the metabolites was also observed, indicating a compartmentalization of the response with differential metabolic patterns. A number of metabolites were changed by Der p 1, mainly related to amino acids metabolism, such as L‐arginine, L‐kynurenine and L‐methionine.ConclusionThis work is the first report on the metabolic response in human bronchial epithelial cells associated with cysteine‐protease Der p 1 activity, which could contribute to allergy development. Moreover, it supports a reformulated epithelial barrier hypothesis that might help to explain allergies and their increasing prevalence. 相似文献
983.
984.
Amitabh B. Suthar Sara Schubert Julie Garon Alexia Couture Amy M. Brown Sana Charania 《Emerging infectious diseases》2022,28(1):148
We compared case definitions for suspected, probable, and confirmed coronavirus disease (COVID-19), as well as diagnostic testing criteria, used in the 25 countries with the highest reported case counts as of October 1, 2020. Of the identified countries, 56% followed World Health Organization (WHO) recommendations for using a combination of clinical and epidemiologic criteria as part of the suspected case definition. A total of 75% of identified countries followed WHO recommendations on using clinical, epidemiologic, and diagnostic criteria for probable cases; 72% followed WHO recommendations to use PCR testing to confirm COVID-19. Finally, 64% of countries used testing eligibility criteria at least as permissive as WHO. We observed marked heterogeneity in testing eligibility requirements and in how countries define a COVID-19 case. This heterogeneity affects the ability to compare case counts, transmission, and vaccine effectiveness, as well as estimates derived from case surveillance data across countries. 相似文献
985.
Margherita Prosperi Elisa Santocchi Letizia Guiducci Jacopo Frinzi Maria Aurora Morales Raffaella Tancredi Filippo Muratori Sara Calderoni 《Nutrients》2022,14(3)
The alteration of the microbiota–gut–brain axis has been recently recognized as a critical modulator of neuropsychiatric health and a possible factor in the etiopathogenesis of autism spectrum disorders (ASD). This systematic review offers practitioners an overview of the potential therapeutic options to modify dysbiosis, GI symptoms, and ASD severity by modulating the microbiota–gut–brain axis in ASD, taking into consideration limits and benefits from current findings. Comprehensive searches of PubMed, Scopus, the Web of Science Core Collection, and EMBASE were performed from 2000 to 2021, crossing terms referred to ASD and treatments acting on the microbiota–gut–brain axis. A total of 1769 publications were identified, of which 19 articles met the inclusion criteria. Data were extracted independently by two reviewers using a preconstructed form. Despite the encouraging findings, considering the variability of the treatments, the samples size, the duration of treatment, and the tools used to evaluate the outcome of the examined trials, these results are still partial. They do not allow to establish a conclusive beneficial effect of probiotics and other interventions on the symptoms of ASD. In particular, the optimal species, subspecies, and dosages have yet to be identified. Considering the heterogeneity of ASD, double-blind, randomized, controlled trials and treatment tailored to ASD characteristics and host-microbiota are recommended. 相似文献
986.
Charlotte M. Dieteren Vivian T. ReckersDroog Sara Schrama Dynothra de Boer Job van Exel 《Health expectations》2022,25(1):333
ContextIt remains unclear whether there would be societal support for a lifestyle criterion for the healthcare priority setting. This study examines the viewpoints of experts in healthcare and the public regarding support for a lifestyle‐related decision criterion, relative to support for the currently applied criteria, in the healthcare priority setting in the Netherlands.MethodsWe conducted a Q methodology study in samples of experts in healthcare (n = 37) and the public (n = 44). Participants (total sample N = 81) ranked 34 statements that reflected currently applied decision criteria as well as a lifestyle criterion for setting priorities in healthcare. The ranking data were subjected to principal component analysis, followed by oblimin rotation, to identify clusters of participants with similar viewpoints.FindingsWe identified four viewpoints. Participants with Viewpoint 1 believe that treatments that have been proven to be effective should be reimbursed. Those with Viewpoint 2 believe that life is precious and every effort should be made to save a life, even when treatment still results in a very poor state of health. Those with Viewpoint 3 accept government intervention in unhealthy lifestyles and believe that individual responsibility should be taken into account in reimbursement decisions. Participants with Viewpoint 4 attribute importance to the cost‐effectiveness of treatments; however, when priorities have to be set, treatment effects are considered most important. All viewpoints were supported by a mix of public and experts, but Viewpoint 1 was mostly supported by experts and the other viewpoints were mostly supported by members of the public.ConclusionsThis study identified four distinct viewpoints on the healthcare priority setting in the Netherlands, each supported by a mix of experts and members of the public. There seems to be some, but limited, support for a lifestyle criterion—in particular, among members of the public. Experts seem to favour the decision criteria that are currently applied. The diversity in views deserves attention when policymakers want to adhere to societal preferences and increase policy acceptance. 相似文献
987.
988.
989.
Tyler C Hein Leigh G Goetschius Vonnie C McLoyd Jeanne Brooks-Gunn Sara S McLanahan Colter Mitchell Nestor L Lopez-Duran Luke W Hyde Christopher S Monk 《Social cognitive and affective neuroscience》2020,15(11):1252
BackgroundChildhood adversity is, unfortunately, highly prevalent and strongly associated with later psychopathology. Recent theories posit that two dimensions of early adversity, threat and deprivation, have distinct effects on brain development. The current study evaluated whether violence exposure (threat) and social deprivation (deprivation) were associated with adolescent amygdala and ventral striatum activation, respectively, in a prospective, well-sampled, longitudinal cohort using a pre-registered, open science approach.MethodsOne hundred and sixty-seven adolescents from the Fragile Families and Child Wellbeing Study completed functional magnetic resonance imaging (fMRI) scanning. Prospective longitudinal data from ages 3, 5 and 9 years were used to create indices of childhood violence exposure and social deprivation. We evaluated whether these dimensions were associated with adolescent brain function in response to threatening and rewarding faces.ResultsChildhood violence exposure was associated with decreased amygdala habituation (i.e. more sustained activation) and activation to angry faces in adolescence, whereas childhood social deprivation was associated with decreased ventral striatum activation to happy faces in adolescence. These associations held when adjusting for the other dimension of adversity (e.g., adjusting for social deprivation when examining associations with violence exposure), the interaction of the two dimensions of adversity, gender, internalizing psychopathology, and current life stress.ConclusionsConsistent with recent theories, different forms of early adversity were associated with region-specific differences in brain activation. 相似文献
990.
Kiran Naqvi MD Elias Jabbour MD Jeffrey Skinner BS MHA Kristin Anderson BS Sara Dellasala BS Musa Yilmaz MD Alessandra Ferrajoli MD Prithviraj Bose MD Philip Thompson MBBS Yesid Alvarado MD Nitin Jain MBBS Koichi Takahashi MD Jan Burger MD Zeev Estrov MD Gautam Borthakur MBBS Naveen Pemmaraju MD Shilpa Paul Pharm D Jorge Cortes MD Hagop M. Kantarjian MD 《Cancer》2020,126(1):67-75