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1.
Endoscopy ; 47(12): 1106-12, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26158241

RESUMEN

BACKGROUND AND AIMS: Currently, eradication of Barrett's epithelium is preferably achieved using radiofrequency ablation (RFA) or spray cryoablation (SCA). However, both modalities suffer from drawbacks such as the need for sizing, multiple deployment steps, large controller units (RFA), imprecise dosing and need for gas-venting (SCA). The new Cryoballoon Focal Ablation System (CbFAS) may address these limitations. This study assessed the safety, feasibility, and dose response of the CbFAS in patients with flat Barrett's epithelium with or without dysplasia. PATIENTS AND METHODS: In this multicenter, prospective non-randomized trial, 39 patients were each treated with one or two ablations of 6, 8, or 10 seconds. Symptoms were assessed immediately and 2 days post-cryoablation. Follow-up endoscopy was performed 6-8 weeks post-procedure to assess response. Outcome parameters were incidence of adverse events, pain, esophageal stricture formation, and ablation response by cryogen dose. RESULTS: Of 62 ablations, 56 (10 with 6 seconds, 28 with 8 seconds, 18 with 10 seconds) were successfully performed. Six ablations failed because of device malfunction (n=3) and procedural or anatomic issues (n=3). Median procedure time was 7 minutes (interquartile range [IQR] 4-10). No major adverse events occurred; six patients experienced a minor mucosal laceration requiring no intervention. Mild pain was reported by 27% of patients immediately after cryoablation and by 14% after 2 days. No strictures were evident at follow-up.  Full squamous regeneration was seen in 47 treated areas (6 [60%] of the 6-second areas; 23 [82%] of the 8-second areas; 18 [100%] of 10-second areas). CONCLUSIONS: Focal cryoablation of Barrett's epithelium with the CbFAS is feasible and safe, resulting in squamous regeneration in the majority of patients.


Asunto(s)
Esófago de Barrett , Criocirugía , Esofagoscopía , Esófago , Dolor Postoperatorio/diagnóstico , Anciano , Esófago de Barrett/diagnóstico , Esófago de Barrett/cirugía , Criocirugía/efectos adversos , Criocirugía/instrumentación , Criocirugía/métodos , Esofagoscopía/efectos adversos , Esofagoscopía/instrumentación , Esofagoscopía/métodos , Esófago/patología , Esófago/cirugía , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Resultado del Tratamiento
2.
Ecol Appl ; 25(8): 2119-31, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26910943

RESUMEN

Global trends in pollinator-dependent crops have raised awareness of the need to support managed and wild bee populations to ensure sustainable crop production. Provision of sufficient forage resources is a key element for promoting bee populations within human impacted landscapes, particularly those in agricultural lands where demand for pollination service is high and land use and management practices have reduced available flowering resources. Recent government incentives in North America and Europe support the planting of wildflowers to benefit pollinators; surprisingly, in North America there has been almost no rigorous testing of the performance of wildflower mixes, or their ability to support wild bee abundance and diversity. We tested different wildflower mixes in a spatially replicated, multiyear study in three regions of North America where production of pollinator-dependent crops is high: Florida, Michigan, and California. In each region, we quantified flowering among wildflower mixes composed of annual and perennial species, and with high and low relative diversity. We measured the abundance and species richness of wild bees, honey bees, and syrphid flies at each mix over two seasons. In each region, some but not all wildflower mixes provided significantly greater floral display area than unmanaged weedy control plots. Mixes also attracted greater abundance and richness of wild bees, although the identity of best mixes varied among regions. By partitioning floral display size from mix identity we show the importance of display size for attracting abundant and diverse wild bees. Season-long monitoring also revealed that designing mixes to provide continuous bloom throughout the growing season is critical to supporting the greatest pollinator species richness. Contrary to expectation, perennials bloomed in their first season, and complementarity in attraction of pollinators among annuals and perennials suggests that inclusion of functionally diverse species may provide the greatest benefit. Wildflower mixes may be particularly important for providing resources for some taxa, such as bumble bees, which are known to be in decline in several regions of North America. No mix consistently attained the full diversity that was planted. Further study is needed on how to achieve the desired floral display and diversity from seed mixes.


Asunto(s)
Abejas/fisiología , Flores/fisiología , Plantas/clasificación , Agricultura , Animales , Animales Salvajes , Biodiversidad , Monitoreo del Ambiente , Polinización/fisiología , Estados Unidos
3.
Phytopathology ; 101(11): 1365-72, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21999160

RESUMEN

Zucchini squash is host to Cucurbit yellow stunting disorder virus (CYSDV), a member of the genus Crinivirus, and Cucumber vein yellowing virus (CVYV), a member of the genus Ipomovirus, both transmitted by the whitefly Bemisia tabaci. Field observations suggest the appearance of new symptoms observed on leaves of zucchini squash crops when both viruses were present. When infected during controlled experiments with CYSDV only, zucchini plants showed no obvious symptoms and the virus titer decreased between 15 and 45 days postinoculation (dpi), after which it was no longer detected. CVYV caused inconspicuous symptoms restricted to vein clearing on some of the apical leaves and the virus accumulated progressively between 15 and 60 dpi. Similar accumulations of virus followed single inoculations with the potyvirus Zucchini yellow mosaic virus (ZYMV) and plants showed severe stunting, leaf deformation, and mosaic yellowing. However, in mixed infections with CYSDV and CVYV, intermediate leaves showed chlorotic mottling which evolved later to rolling, brittleness, and complete yellowing of the leaf lamina, with exception of the veins. No consistent alteration of CVYV accumulation was detected but the amounts of CYSDV increased ≈100-fold and remained detectable at 60 dpi. Such synergistic effects on the titer of the crinivirus and symptom expression were not observed when co-infected with ZYMV.


Asunto(s)
Coinfección/virología , Crinivirus/fisiología , Cucurbita/virología , Enfermedades de las Plantas/virología , Potyviridae/fisiología , Animales , Crinivirus/crecimiento & desarrollo , Crinivirus/aislamiento & purificación , Cucumis sativus/crecimiento & desarrollo , Cucumis sativus/virología , Cucurbita/crecimiento & desarrollo , Hemípteros/virología , Insectos Vectores/virología , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/virología , Potyviridae/crecimiento & desarrollo , Potyviridae/aislamiento & purificación , Potyvirus/crecimiento & desarrollo , Potyvirus/aislamiento & purificación , Potyvirus/fisiología , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Estaciones del Año , Factores de Tiempo
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