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Blythe A. Layton Devrim Kaya Christine Kelly Kenneth J. Williamson Dana Alegre Silke M. Bachhuber Peter G. Banwarth Jeffrey W. Bethel Katherine Carter Benjamin D. Dalziel Mark Dasenko Matthew Geniza Andrea George Anne-Marie Girard Roy Haggerty Kathryn A. Higley Denise M. Hynes Jane Lubchenco Katherine R. McLaughlin F. Javier Nieto Aslan Noakes Matthew Peterson Adriana D. Piemonti Justin L. Sanders Brett M. Tyler Tyler S. Radniecki 《Environmental health perspectives》2022,130(6)
Background: Positive correlations have been reported between wastewater SARS-CoV-2 concentrations and a community’s burden of infection, disease or both. However, previous studies mostly compared wastewater to clinical case counts or nonrepresentative convenience samples, limiting their quantitative potential.Objectives: This study examined whether wastewater SARS-CoV-2 concentrations could provide better estimations for SARS-CoV-2 community prevalence than reported cases of COVID-19. In addition, this study tested whether wastewater-based epidemiology methods could identify neighborhood-level COVID-19 hotspots and SARS-CoV-2 variants.Methods: Community SARS-CoV-2 prevalence was estimated from eight randomized door-to-door nasal swab sampling events in six Oregon communities of disparate size, location, and demography over a 10-month period. Simultaneously, wastewater SARS-CoV-2 concentrations were quantified at each community’s wastewater treatment plant and from 22 Newport, Oregon, neighborhoods. SARS-CoV-2 RNA was sequenced from all positive wastewater and nasal swab samples. Clinically reported case counts were obtained from the Oregon Health Authority.Results: Estimated community SARS-CoV-2 prevalence ranged from 8 to 1,687/10,000 persons. Community wastewater SARS-CoV-2 concentrations ranged from 2.9 to gene copies per liter. Wastewater SARS-CoV-2 concentrations were more highly correlated (Pearson’s ; ) with community prevalence than were clinically reported cases of COVID-19 (Pearson’s ; ). Monte Carlo simulations indicated that wastewater SARS-CoV-2 concentrations were significantly better than clinically reported cases at estimating prevalence (). In addition, wastewater analyses determined neighborhood-level COVID-19 hot spots and identified SARS-CoV-2 variants (B.1 and B.1.399) at the neighborhood and city scales.Discussion: The greater reliability of wastewater SARS-CoV-2 concentrations over clinically reported case counts was likely due to systematic biases that affect reported case counts, including variations in access to testing and underreporting of asymptomatic cases. With these advantages, combined with scalability and low costs, wastewater-based epidemiology can be a key component in public health surveillance of COVID-19 and other communicable infections. https://doi.org/10.1289/ EHP10289相似文献
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Ionela Andreea Neacsu Sorina-Alexandra Leau Stefania Marin Alina Maria Holban Bogdan-Stefan Vasile Adrian-Ionut Nicoara Vladimir Lucian Ene Coralia Bleotu Mdlina Georgiana Albu Kaya Anton Ficai 《Materials》2021,14(5)
Microbial infections associated with skin diseases are frequently investigated since they impact on the progress of pathology and healing. The present work proposes the development of freeze-dried, glutaraldehyde cross-linked, and non-cross-linked biocomposite dressings with a porous structure, which may assist the reepithelization process through the presence of collagen and carboxymethylcellulose, along with a therapeutic antimicrobial effect, due to silver nanoparticles (AgNPs) addition. Phisyco-chemical characterization revealed the porous morphology of the obtained freeze-dried composites, the presence of high crystalline silver nanoparticles with truncated triangular and polyhedral morphologies, as well as the characteristic absorption bands of collagen, silver, and carboxymethylcellulose. In vitro tests also assessed the stability, functionality, and the degradability rate of the obtained wound-dressings. Antimicrobial assay performed on Gram-negative (Escherichia coli), Gram-positive (Staphyloccocus aureus) bacteria, and yeast (Candida albicans) models demonstrated that composite wound dressings based on collagen, carboxymethylcellulose, and AgNPs are suitable for skin lesions because they prevent the risk of infection and have prospective wound healing capacity. Moreover, the cell toxicity studies proved that the obtained materials can be used in long time treatments, with no cytotoxic effects. 相似文献
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M. Erkoçoğlu A. Kaya D. Azkur Ş. Özyer C. Özcan M. Beşli E. Civelek C.N. Kocabaş 《Allergologia et immunopathologia》2013,41(3):169-175
BackgroundEmerging evidence suggests that sex steroid hormones may influence respiratory symptoms. The existing literature about the role of oral contraceptive pill (OCP) on respiratory disease is scarce and conflicting especially during the adolescent period. In this study, we aimed to investigate the effect of OCPs on current wheezing among adolescents and young adults.MethodsA questionnaire was administered face-to-face to adolescents and young women by a physician. The questionnaire included ISAAC survey-comprised questions on ever wheezing, current wheezing, allergic diseases, smoking history (active or passive), and family history of allergic diseases and questions on OCP usage status. The effect of OCPs on wheezing was evaluated by logistic regression analysis.ResultsA total of 487 subjects aged between 11.3 and 25.6 years participated in the study and 196 (40.2%) reported that they had used OCPs. 7.4% of the participants had physician-diagnosed asthma and 10.3% of them were active smokers. It was detected that OCPs were associated with increased risk for current wheezing (odds ratio, 2.36; 95% CI, 1.25–4.47 adjusted for asthma and current smoker) and this risk was related with the usage during the past year.ConclusionYoung women taking oral contraceptives had a higher rate of current wheezing, suggesting that sex steroids may be of importance for respiratory health. 相似文献
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Persistent left superior vena cava accompanying congenital heart disease in children: Experience of a tertiary care center 下载免费PDF全文
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Localized colitis cystica profunda is a rare, benign disease of the lower gastro-intestinal tract, usually presenting as a rectal mass and characterized microscopically by the presence of mucus-filled cysts in the submucosa. Knowledge of this particular pathological entity is important as it can mimic a well differentiated adenocarcinoma of the rectum and therefore could lead to unnecessary surgical resection. We present a case of colitis cystica profunda misdiagnosed as adenocarcinoma based on their similar clinical picture and histological features. 相似文献