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1.
Mar Pollut Bull ; 173(Pt A): 112988, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34583250

RESUMO

In recent years, dense Alexandrium ostenfeldii blooms have been reported in different coastal areas. In this study, we report for the first time the occurrence of A. ostenfeldii blooms associated with the detection of paralytic shellfish toxins (PSTs) in the Peruvian scallop (Argopecten purpuratus) from Paracas Bay. Alexandrium ostenfeldii blooms occurred at the end of summer and early fall, after the increase of riverine input and under stratified conditions following a decrease in wind velocity. The highest abundances occurred during warm sea surface temperatures (18-27 °C). High PST concentrations that exceed the maximum permissible level (800 µg STX eq. kg-1) occurred even under low A. ostenfeldii abundances (20 × 103 cells l-1). Our results contribute to a better understanding of the dynamics of A. ostenfeldii in coastal systems influenced by riverine inputs and upwelling and can be used to improve monitoring programs and allow the implementation of mitigation measures along the Peruvian coast.


Assuntos
Dinoflagellida , Pectinidae , Animais , Baías , Peru , Frutos do Mar
2.
Ecotoxicol Environ Saf ; 214: 112045, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33711577

RESUMO

Vegetated coastal ecosystems have an important role as contaminant filters. Temporal variations in concentrations, enrichment factors (EF), and fluxes of trace elements (As, Cd, Co, Cr, Cu, Ni, Pb, V, and Zn) were evaluated in 210Pb-dated sediment cores from salt marsh and seagrass ecosystems at San Quintín Bay (Mexican northern Pacific). Trace element contamination was negligible in seagrass sediments, but minor to severe, depending on the element, in salt marsh cores, owing to higher organic carbon and fine sediment contents. EF temporal variation in salt marsh cores was attributed to agriculture technology changes (e.g. installation of greenhouses, and improved irrigation and fertilization systems). Trace element flux ratios increased during the past 100 years, likely caused by steadily increasing sediment accumulation rates promoted by land-use changes in the catchment. The conservation of salt marsh areas is important to preserve their function as contaminants biofilters and the health of adjacent ecosystems.


Assuntos
Monitoramento Ambiental , Oligoelementos/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Agricultura , Ecossistema , Sedimentos Geológicos , México
3.
Sci Total Environ ; 675: 581-593, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31030163

RESUMO

Coastal vegetated ecosystems constitute very productive habitats, characterized by efficient Corg sequestration and long-term preservation in sediments, so they play an important role in climate change mitigation. The temporal evolution of Corg content, stocks and burial rates were evaluated in seagrass and salt marsh habitats in San Quintin Bay (northeast Pacific, Mexico) by using 210Pb-dated sediment cores. Salt marsh cores were characterized by fine-grained sediments, higher salinities, lower terrigenous input and lower mass accumulation rates (MAR: 0.01-0.03 g cm-2 yr-1) than seagrass cores (MAR: 0.02-3.21 g cm-2 yr-1). Accumulation rates in both habitats steadily increased throughout the past century most likely because of soil erosion promoted by land use changes in the surroundings. The Corg stocks were highest in salt marsh cores (12.2-53.6 Mg ha-1 at 10 cm depth; 259-320 Mg ha-1 at 1 m depth) than in seagrass cores (5.7-14.4 Mg ha-1, and 80-98, Mg ha-1, respectively), whereas Corg burial rates were considerably lower in salt marsh (13-60 g m-2 yr-1) than in seagrass (9-144 g m-2 yr-1) habitats, and the temporal variations observed in Corg burial rates were mostly driven by changes in the accumulation rates. The overall Corg stock (485 ±â€¯51 Gg C) for both habitats together was comparable to the carbon emissions of a major city nearby. Our results highlight the need to protect these environments as relevant carbon reservoirs.

4.
Sci Total Environ ; 621: 548-557, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29195203

RESUMO

To evaluate the relationship of changes in organic-walled dinoflagellate cyst (dinocyst) fluxes to sediments with environmental variables (air and sea surface temperatures, El Niño conditions, rainfall, and terrigenous index), cyst assemblages were analyzed in a 210Pb-dated sediment core (~100years) from the pristine San José Lagoon (San José Island, SW Gulf of California). The dinocyst abundance ranged from 3784 to 25,108cystsg-1 and fluxes were of the order of 103-104cystscm-2yr-1. Lingulodinium machaerophorum, Polysphaeridium zoharyi and Spiniferites taxa accounted for 96% of the total dinocyst assemblages, and the abundances of these species increased towards the core surface. P. zoharyi fluxes increased from about 1965 onwards. Redundancy analyses, showed that mean minimum air temperature and terrigenous index were the key factors governing dinocyst fluxes. In this study, dinocyst fluxes of dominant taxa had responded to changes in climate-dependent environmental variables during the past ~20years; this may also be the case in other subtropical coastal lagoons.


Assuntos
Clima , Dinoflagellida/crescimento & desenvolvimento , Monitoramento Ambiental , Sedimentos Geológicos , California , Oceano Pacífico , Temperatura
5.
Rev. cuba. obstet. ginecol ; 41(3): 266-274, jul.-set. 2015. ilus
Artigo em Espanhol | CUMED | ID: cum-63816

RESUMO

Introducción: en la actualidad el cáncer constituye un serio problema de salud en Cuba y el mundo.Objetivos: diseñar y aplicar un programa de intervención educativa para incrementar el conocimiento de los factores epidemiológicos asociados al cáncer cervicouterino. Identificar la presencia de estos factores en mujeres con citologías alteradas y determinar el nivel de conocimientos en mujeres supuestamente sanas.Métodos: se realizó una investigación cuasi experimental, longitudinal en el Consejo Popular Zona Sur, policlínico 5 de Septiembre, Consolación del Sur, periodo de enero a diciembre de 2012. Universo de 687 féminas y una muestra de 248, de ellas 48 con citologías positivas y 200 supuestamente sanas. Para el procesamiento de la información se utilizó la estadística descriptiva e inferencial aplicándose la prueba de McNemar para evaluar diferencias significativas entre variables.Resultados: la citología alterada fue más frecuente en el grupo de edad de 30 a 34 años y la neoplasia intracervical grado I la que más se evidenció, el 91,6 por ciento de las 48 mujeres citologías positivas tenían infección asociada, de las cuales el 39,5 por ciento era el Virus del Papiloma Humano. El 72,9 por ciento comenzaron sus relaciones sexuales a los 17 años de edad o menos, el 56 por ciento tenían tres partos o más.Conclusiones: En las mujeres supuestamente sanas vistió bajo nivel de conocimientos sobre factores epidemiológicos asociados al cáncer cervicouterino. Después de aplicada la intervención aumentó el conocimiento de los factores epidemiológicos asociados al cáncer cervicouterino(AU)


Assuntos
Humanos , Feminino , Neoplasias do Colo do Útero/epidemiologia , Cuba , Fatores Epidemiológicos , Citodiagnóstico/métodos
7.
Bol. Hosp. San Juan de Dios ; 54(3): 150-152, may-jun. 2007.
Artigo em Espanhol | LILACS | ID: lil-475747

RESUMO

La insuficiencia medular es un síndrome hematológico; de pronóstico siempre reservado; que reconoce dos mecanismos etiopatogénicos: la aplasia medular y la mieloptisis. La primera es de naturaleza benigna y recuperable (50 por ciento) y la segunda maligna. Ambas se manifiestan clínicamente por una pancitopenia de la sangre periférica, la que se traduce por la asociación de un síndrome anémico normocítico y normocrómico arregenerativo, uno infeccioso febril y uno purpúrico. El diagnóstico clínico de insuficiencia medular es fácil, no así su tratamiento, especialmente en las mieloptisis.


Assuntos
Humanos , Doenças da Medula Óssea/diagnóstico , Doenças da Medula Óssea/terapia , Leucopenia/terapia , Neutropenia/terapia , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/terapia , Hematopoese , Mielopoese , Pancitopenia
8.
Rev. cienc. med. Pinar Rio ; 9(2): 72-81, abr.-jun. 2005.
Artigo em Espanhol | LILACS | ID: lil-739599

RESUMO

Tomando en consideración la importancia del problema de salud ocasionado por el Virus de la Hepatitis Tipo B (V.H.B), así como lo orientado por el Ministerio de Salud Pública (MINSAP) en el Programa contra la Hepatitis Viral Tipo B, hemos estudiado el cumplimiento del esquema de vacunación, en trabajadores de la Salud (T.S), la respuesta inmune en ellos y la forma de intervenir para incrementar dicha respuesta en los que hayan tenido irregularidades y lo necesiten. En estos casos se realizó la aplicación de una dosis de 20 microgramos de la Vacuna Heberbiovac HB midiendo la cantidad de anticuerpos (Ac) antes y l mes después del refuerzo. El número de trabajadores pesquisados fue de 41 detectándose irregularidades (2 dosis) en el 31%. Se demostró menor seroprotección e hiperespuesta cuando solo se administraron 2 dosis. En estos trabajadores donde se utilizó el refuerzo se incrementó la respuesta inmune. Los no seroprotegidos en el pesquisaje inicial no alcanzaron valores de hipe respuesta coincidiendo con edad > 44 años. Se recomienda incrementar la cultura de buenas prácticas en nuestro sector desde el punto de vista Biológico y Educativo.


Considering the importance of the health problem by viral type B hepatitis (V.H.B.) as well as the guideline of Public Health Ministry (MINSAP) in the program anti type B viral hepatitis it was studied the fulfilment of vaccination scheme in health workers, the immune response in those patients with abnormalities and those that needed it. In such cases a dose of 20 microgramus of Heberbiovac Vaccine HB was applied measuring the antibodies (Ac) before and one month after the reinforcing doses, the immunological response was increased. No-serum protected patients in the initial study did not reach hyperresponse values coinciding with age over 44. it is recommended to increase the good practices in our sectors from the biological and educational points of view.

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