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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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Objective: Various foods play important role in the pathogenesis of gastroesophageal reflux disease (GERD). These foods are shown to increase gastroesophageal reflux symptoms via various mechanisms and majority of these foods also contain nickel. The purpose of this study is to evaluate the relationship between Nickel sensitivity and GERD.Material and methods: Fifty-four patients diagnosed with GERD and 50 healthy volunteers who were admitted to our gastroenterology outpatient clinic were took part in the study. European standard patch test series, nickel-containing test units and corticosteroids were applied to the patient body; upper back. Evaluation was performed according to the scheme of the International Contact Dermatitis Research Group (ICDRG). The positive and negative reactions were recorded at the hours of 48, 72 and 96. Following the test implementations, 7?days later, the tests were reevaluated for late reactions. Statistics package for Social Sciences (SPSS) 17 package program was used for statistical evaluation and results of tests were compared between groups with the Chi-squared test. p?0.05 was considered statistically significant.Results: Individuals in both groups were statistically similar in terms of age and gender. Nickel sensitivity was found to be positive in 48.2 and %22 of the GERD patients and control group, respectively. Difference between groups was statistically significant (p?=?0.008).Conclusions: Nickel sensitivity was significantly higher in GERD patients compared to the control group. In addition to imbalance between defensive and aggressive forces of the esophagus, there seems to be an association between nickel sensitivity and GERD. 相似文献
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Effects of octreotide and propranolol on colonic mucosa in rats with portal hypertensive colopathy 总被引:2,自引:0,他引:2
BACKGROUND/AIMS: The aim of the study is to clarify the effects of octreotide and propranolol, agents used in the treatment of portal hypertension, on mucosal changes in portal hypertensive colopathy. METHODOLOGY: Portal hypertension was induced in all rats by partial portal vein ligation, and after the operation all rats were caged for a 10-week period. Then, animals were divided into three groups and for two weeks medical treatment were administered to the individual groups as follows: Control group, saline 0.5 mL/day, intraperitoneally. Octreotide group, octreotide 100 micrograms/kg/12 hours, subcutaneously. Propranolol group, propranolol 20 mg/kg/day, intraperitoneally. In order to assess the portal hypertensive colopathy, criteria such as mean diameters of dilated vessels in colonic mucosa, and the existence of mucosal edema, capillary ectasia, hyperemia and hemorrhage, inflammation were used. RESULTS: When parameters were compared for the control versus propranolol groups, mucosal edema and hyperemia and hemorrhage criteria were found to be significant for the propranolol group; control versus octreotide groups, mucosal edema, capillary ectasia, and hyperemia and hemorrhage criteria were found to be significant for the octreotide group; octreotide versus propranolol groups, capillary ectasia and mucosal edema criteria were found to be significant for the octreotide group. CONCLUSIONS: The mucosal changes in portal hypertensive colopathy could be corrected by drugs modifying portal blood flow, octreotide may find a place in the treatment of portal hypertensive colopathy. 相似文献
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The efficiency of Poly(ADP‐Ribose) Polymerase (PARP) cleavage on detection of apoptosis in an experimental model of testicular torsion 下载免费PDF全文
Pınar Aslan Koşar Hamdi Tuncer Abdülhadi Cihangir Uğuz Javier Espino Palma Hakan Darıcı İbrahim Onaran Bilal Çiğ Alim Koşar Ana Beatriz Rodriguez Moratinos 《International journal of experimental pathology》2015,96(5):294-300
The aim of this study was to evaluate the histopathological and apoptotic changes occurring in the rat ipsilateral and contralateral testes, after experimental spermatic cord torsion, and to explore and the role of poly(ADP‐ribose) polymerase (PARP) cleavage in testicular torsion–detorsion injury. A total of 37 Wistar albino rats were subjected to 720° unilateral spermatic cord torsion for 1, 2 and 4 h, followed by 4‐h reperfusion, or else to a sham operation (control group). Histology of the testicle was evaluated using haematoxylin–eosin (H&E) staining and Johnsen's scoring system. Germ cell apoptosis was evaluated via active caspase‐3 immunostaining, and PARP expression levels were evaluated via Western blotting. The mean Johnsen's tubular biopsy scores (JTBS) of the ipsilateral testicles were lower for all torsion groups than for the controls (P < 0.05), but the JTBS of the contralateral testicles were only lower in the 4‐h torsion group (P < 0.05). The mean apoptosis score (AS) of the ipsilateral and contralateral testicles was significantly higher in the torsion groups than in the sham group. AS increased correlatively with torsion time, in both testicles. The effect of testicular torsion on PARP cleavage was time dependent, with the highest effect observed after 4 h of testicular torsion (P < 0.05). Testicular torsion caused time‐dependent histological changes, apoptosis and increases in PARP cleavage. Our results suggest that testicular torsion–detorsion injury caused cell damage and germ cell apoptosis that apparently involved cleavage of PARP. Increased PARP cleavage could, in turn, lead to enhanced apoptosis. 相似文献
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