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A. Agustí-Mejias F. Messeguer Badia R. García Ruiz V. Oliver Martínez V. Alegre de Miquel 《Actas dermo-sifiliográficas》2012,103(5):394-400
BackgroundAtypical lentiginous nevus (of the elderly) is a peculiar form of dysplastic nevus. Clinically, this condition can resemble malignant melanoma and histologically, it has a lentiginous pattern with variable degrees of atypia and an absence of dermal nests. These features may lead to an erroneous diagnosis of lentigo maligna melanoma or lentiginous melanoma.Material and methodsWe reviewed 14 cases of atypical lentiginous nevus diagnosed at the dermatology department of Hospital General de Valencia in Valencia, Spain between December 2007 and March 2009. We studied the clinical and histopathologic features of the lesions after hematoxylin-eosin, Melan-A, and Ki-67 staining and compared our results to data reported in the literature.ResultsFour (28%) of the 14 patients (7 men, 7 women) were under 50 years of age. Clinically, most of the lesions (8/14) resembled atypical nevi and they were all located on the back. Histologically, they all had irregular lentiginous epidermal hyperplasia, with a proliferation of individual melanocytes only in the basal layer of the epidermis and an absence of dermal nests. Focal upward migration of melanocytes into the epidermis was present in just 4 cases. All the lesions had cellular atypia, which was moderate in 85% of cases. The Ki-67 proliferation index was low (<5%) in all the lesions analyzed.ConclusionsAtypical lentiginous nevi, which can be classified as atypical pigmented lesions with a lentiginous pattern, may clinically and histologically resemble melanoma. Our findings support earlier reports that both clinical and histologic findings may suggest a diagnosis of dysplastic nevus. All of the patients in our series are healthy and free of recurrence after 18 months or longer. 相似文献
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This study aimed to test the effectiveness of ankle taping on the limitation of forced supination during a change of direction, as well as the losses of effectiveness after a 30-minute training session. Fifteen young men with no ankle injury volunteered for the study. The static and dynamic ranges of movement (ROM) were measured before and after a training session. The dynamic measurements were recorded using high-speed 3D photogrammetry. The differences between static and dynamic measures of ankle supination and plantar flexion were significant. The losses of effectiveness during supination and ankle plantar flexion restriction were 42.3 % and 47.6 %, respectively. Ankle taping was effective in restricting the maximal static ROMs before a training session, but the effectiveness decreased after 30 min of training. The present study shows the necessity of performing dynamic ROM analysis of sports techniques involved in the ankle sprain mechanism in order to determine the degree of tape restriction after a training session, because there were differences between static and dynamic ankle ROMs. The lack of effects on the restriction of the dynamic plantar flexion would bring into question the necessity of ankle taping in subjects without previous injuries. 相似文献
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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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