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1.
Am J Physiol Gastrointest Liver Physiol ; 309(3): G135-45, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-26089336

RESUMEN

Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation.


Asunto(s)
Adaptación Biológica/fisiología , Intestinos , Síndrome del Intestino Corto/metabolismo , Animales , Antimetabolitos/farmacología , Bromodesoxiuridina/farmacología , Proliferación Celular , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Modelos Animales de Enfermedad , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Mucosa Intestinal/patología , Intestinos/patología , Intestinos/fisiopatología , Intestinos/cirugía , Masculino , Células Madre/fisiología , Pérdida de Peso , Pez Cebra , Proteínas de Pez Cebra/metabolismo
2.
J Am Med Inform Assoc ; 4(2): 112-24, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9067877

RESUMEN

OBJECTIVE: To identify impediments to the successful transfer and implementation of packaged information systems through large, divisionalized health services. DESIGN: A case analysis of the failure of an implementation of a critical application in the Public Health System of the State of New South Wales, Australia, was carried out. This application had been proven in the United States environment. MEASUREMENTS: Interviews involving over 60 staff at all levels of the service were undertaken by a team of three. The interviews were recorded and analyzed for key themes, and the results were shared and compared to enable a continuing critical assessment. RESULTS: Two components of the transfer of the system were considered: the transfer from a different environment, and the diffusion throughout a large, divisionalized organization. The analyses were based on the Scott-Morton organizational fit framework. In relation to the first, it was found that there was a lack of fit in the business environments and strategies, organizational structures and strategy-structure pairing as well as the management process-roles pairing. The diffusion process experienced problems because of the lack of fit in the strategy-structure, strategy-structure-management processes, and strategy-structure-role relationships. CONCLUSION: The large-scale developments of integrated health services present great challenges to the efficient and reliable implementation of information technology, especially in large, divisionalized organizations. There is a need to take a more sophisticated approach to understanding the complexities of organizational factors than has traditionally been the case.


Asunto(s)
Sistemas de Información Administrativa , Administración en Salud Pública , Transferencia de Tecnología , Capacitación de Usuario de Computador , Humanos , Relaciones Interprofesionales , Modelos Organizacionales , Nueva Gales del Sur , Cultura Organizacional , Innovación Organizacional , Proyectos Piloto , Análisis de Sistemas , Interfaz Usuario-Computador
3.
West Indian Med J ; 53(2): 66-70, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15199713

RESUMEN

The concentrations of 28 elements, in hand-made cigars, "rope" tobacco and freshly picked tobacco leaves from the parish of Manchester in central Jamaica, were compared with locally packaged and imported cigarettes and cigars. Except for chromium and vanadium, which are lower in the imported products, the elemental concentrations of all the brands sold in Jamaica are rather similar. The means for aluminium, cadmium, caesium, cerium, chromium, iron, thorium, uranium, vanadium and zinc for the Manchester material exceed the maximum values of the other tobaccos. The significant concentrations of heavy metals, and especially cadmium, which is about 50 times that of commercial cigarettes, reflect the known high concentrations in the soils in the region. This tobacco is not filtered and the smoke contains 50% of the cadmium. This, and the concentrations of radioactive elements, may indicate an additional health risk compared with commercial cigarettes. A study of three samples of marijuana indicates a similar level of risk from heavy metals.


Asunto(s)
Cannabis/química , Nicotiana/química , Oligoelementos/análisis , Jamaica
4.
West Indian Med J ; 52(2): 118-23, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12974061

RESUMEN

The results of five years of radiation monitoring of 590 radiation workers in Jamaica and an additional 88 in Barbados and The Turks and Caicos Islands show that the annual dose absorbed by Caribbean radiation workers is, with a single exception, well within the internationally accepted limits of 20 mSv per year. There were few cases of relatively high exposures. The dose equivalent of the radiation workers by category agrees with international trends; workers in nuclear medicine receive the highest doses and dental radiologists the lowest. The collective Effective Dose Equivalent has been calculated for each of the monitored populations and certain trends identified. The risk for development of fatal cancers from the occupational doses reported was very low. Consistent monitoring will identify aberrant conditions quickly and help maintain that record.


Asunto(s)
Neoplasias Inducidas por Radiación/prevención & control , Exposición Profesional/efectos adversos , Centrales Eléctricas , Monitoreo de Radiación/métodos , Dosimetría Termoluminiscente , Región del Caribe , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Salud Laboral , Dosis de Radiación , Protección Radiológica/métodos , Medición de Riesgo
5.
Appl Radiat Isot ; 71 Suppl: 96-101, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22867747

RESUMEN

The main task was to evaluate possible radon risk to the public and workers in four caves of economical importance. Green Grotto Cave is a large labyrinthine limestone cave, open to the tourism; kept Rn concentration in the range 30-40 Bq m(-3). Xtabil a coral limestone sea cave is part of a beach resort resulted in very low radon concentration of 10 Bq m(-3). Windsor is an intricate limestone cave system showed Rn concentration in the range 250-350 Bq m(-3). Whereas the Oxford caves, is situated in a region of high radioactivity in soil due to the bauxite mines, reached a maximum of 2592 Bq m(-3).


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Monitoreo de Radiación/métodos , Radón/análisis , Contaminación del Aire Interior/análisis , Exposición a Riesgos Ambientales/análisis , Geografía , Jamaica
6.
West Indian med. j ; 52(2): 118-123, Jun. 2003.
Artículo en Inglés | LILACS | ID: lil-410780

RESUMEN

The results of five years of radiation monitoring of 590 radiation workers in Jamaica and an additional 88 in Barbados and The Turks and Caicos Islands show that the annual dose absorbed by Caribbean radiation workers is, with a single exception, well within the internationally accepted limits of 20 mSv per year. There were few cases of relatively high exposures. The dose equivalent of the radiation workers by category agrees with international trends; workers in nuclear medicine receive the highest doses and dental radiologists the lowest. The collective Effective Dose Equivalent has been calculated for each of the monitored populations and certain trends identified. The risk for development of fatal cancers from the occupational doses reported was very low. Consistent monitoring will identify aberrant conditions quickly and help maintain that record


Asunto(s)
Humanos , Masculino , Femenino , Centrales Eléctricas , Dosimetría Termoluminiscente , Exposición Profesional/efectos adversos , Monitoreo de Radiación/métodos , Neoplasias Inducidas por Radiación/prevención & control , Dosis de Radiación , Dosis Máxima Tolerada , Medición de Riesgo , Protección Radiológica/métodos , Región del Caribe , Relación Dosis-Respuesta en la Radiación , Salud Laboral
7.
West Indian med. j ; 53(2): 66-70, Mar. 2004.
Artículo en Inglés | LILACS | ID: lil-410535

RESUMEN

The concentrations of 28 elements, in hand-made cigars, [quot ]rope[quot ] tobacco and freshly picked tobacco leaves from the parish of Manchester in central Jamaica, were compared with locally packaged and imported cigarettes and cigars. Except for chromium and vanadium, which are lower in the imported products, the elemental concentrations of all the brands sold in Jamaica are rather similar. The means for aluminium, cadmium, caesium, cerium, chromium, iron, thorium, uranium, vanadium and zinc for the Manchester material exceed the maximum values of the other tobaccos. The significant concentrations of heavy metals, and especially cadmium, which is about 50 times that of commercial cigarettes, reflect the known high concentrations in the soils in the region. This tobacco is not filtered and the smoke contains 50 of the cadmium. This, and the concentrations of radioactive elements, may indicate an additional health risk compared with commercial cigarettes. A study of three samples of marijuana indicates a similar level of risk from heavy metals


Asunto(s)
Cannabis/química , Oligoelementos/análisis , Nicotiana/química , Jamaica
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