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1.
Theriogenology ; 227: 144-150, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39068823

RESUMEN

One hundred and forty bitches and their offspring (689 puppies) were involved in this study. The influence of different maternal features such as age, breed (brachycephalic/non-brachycephalic), previous births (primiparous/multiparous), health status (complete/incomplete) and litter size over the type of cesarean sections (scheduled/emergency), the neonatal survival, and the incidence of congenital malformations were also examined. Scheduled cesareans were predominant (104/140), of which 90 % were brachycephalic breeds and females were mostly between 2 and 4 years old (54.8 %), multiparous (88.4 %) and with a correct health status (67.3 %). Emergency cesarean sections mainly involved non-brachycephalic breeds (80 %) and were carried out mostly in females under 4 years of age (72.2 %), primiparous (77.7 %), with incomplete health status and a large litter size (47.2 %). Perinatal mortality was notably higher in emergency C-sections (3.25 % and 13.3 %, scheduled and emergency C-sections, respectively); the highest incidence of neonatal mortality was recorded in young females (<2, 2-4 years old), primiparous and with incomplete health status. Congenital anomalies were observed in 4.50 % (31/689) of the puppies, with anasarca (38.71 %) and cleft palate (29.03 %) being the most frequently observed malformations. A higher incidence of congenital malformations was detected in puppies from dams with incomplete sanitary health and from inbreeding cross. Overall, the study provides valuable insights into the complex interplay between maternal characteristics and cesarean outcomes. Appropriate genetic selection, good sanitary health conditions, and the age of the reproducers, are pivotal factors in planning for gestation and improving the survival of neonates.


Asunto(s)
Cesárea , Animales , Perros , Femenino , Embarazo , Cesárea/veterinaria , Tamaño de la Camada , Animales Recién Nacidos
2.
Chempluschem ; 89(7): e202400122, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38578430

RESUMEN

Collagen-based aerogels have great potential for topical biomedical applications. Collagen's natural affinity with skin, biodegradability, and gelling behavior are compelling properties to combine with the structural integrity of highly porous matrices in the dry form (aerogels). This work aimed to produce a novel collagen-based aerogel and to perform the material's solid-state and physicochemical characterization. Aerogels were obtained by performing different solvent exchange approaches of a collagen-gelled extract and drying the obtained alcogels with supercritical CO2. The resulting aerogels showed a sponge-like structure with a relatively dense mesoporous network with a specific surface area of 201-203 m2/g, a specific pore volume of 1.08-1.15 cm3/g, and a mean pore radius of ca. 14.7 nm. Physicochemical characterization confirmed that the obtained aerogels are composed of pure collagen, and the aerogel production process does not impact protein tertiary structure. Finally, the material swelling behavior was assessed at various pH values (4, 7, and 10). Collagen aerogels presented a high water uptake capacity up to ~2700 wt. %, pH-dependent stability, and swelling behavior in aqueous media. The results suggest that this collagen aerogel could be a promising scaffold candidate for topical biomedical applications.


Asunto(s)
Administración Tópica , Colágeno , Geles , Animales , Colágeno/administración & dosificación , Colágeno/química , Geles/administración & dosificación , Geles/química , Concentración de Iones de Hidrógeno , Porosidad , Piel/efectos de los fármacos
3.
Sci Total Environ ; 920: 170609, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38316296

RESUMEN

Spatial and temporal variations of mercury (Hg) concentrations, enrichment, and potential ecological risks were studied in a suite of lead-210 (210Pb) dated sediment cores from 13 Wider Caribbean Region coastal environments. Broad variability of Hg concentrations (19-18761 ng g-1) was observed, encompassing even background levels (38-100 ng g-1). Most Hg concentration profiles exhibited a characteristic upward trend, reaching their peak values in the past two decades. Most of the sediment sections, showing from moderately to very severe Hg enrichment, were found in cores from Havana Bay and Sagua River Estuary (Cuba), Port-au-Prince Bay (Haiti), and Cartagena Bay (Colombia). These were also the most seriously contaminated sites, which can be considered regional Hg 'hotspots'. Both Havana Bay and Port-au-Prince Bay reportedly receive waste from large cities with populations exceeding 2 million inhabitants, and watersheds affected by high erosion rates. The records from the Sagua River Estuary and Cartagena Bay reflected historical Hg contamination associated with chloralkali plants, and these sites are of very high ecological risk. These results constitute a major contribution to the scarce regional data on contaminants in the Wider Caribbean Region and provide reference information to support the evaluation of the effectiveness of the Minamata Convention.

4.
Nucleus (La Habana) ; (60): 35-40, jul.-dic. 2016.
Artículo en Español | LILACS | ID: biblio-829300

RESUMEN

En este trabajo se sistematizan algunos resultados alcanzados en la aplicación de la radiocronología de sedimentos marinos para la reconstrucción de bases de datos y el conocimiento de la evolución de la contaminación ambiental en cuatro ecosistemas costeros de relevancia nacional: las bahías de Cienfuegos y la Habana, así como los estuarios de los ríos Sagua y La Coloma en el Golfo de Batabanó. Se seleccionaron flujos de metales pesados y compuestos orgánicos persistentes que fueron discutidos para estos ecosistemas. Se mostró la eficacia de la radiocronología como herramienta para la gestión ambiental y el conocimiento de los procesos temporales de contaminación en el medio acuático


The results achieved in the implementation of the radiochronology of marine sediments for the reconstruction of databases and knowledge of the evolution of environmental pollution in four coastal ecosystems of national significance are presented in this paper Fluxes of selected heavy metals and persistent organic compounds are discussed for the Cienfuegos and Havana bays and Sagua and La Coloma estuaries. Finally, is showed the effectiveness of radiochronology of sediments as a useful tool for environmental management and knowledge of temporal processes of pollution in the aquatic environment

5.
Rev. biol. trop ; 64(1): 177-188, ene.-mar. 2016. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-843269

RESUMEN

AbstractHypoxia is the depletion of dissolved oxygen below 2 mg O2/L. Relatively few studies on hypoxia and its effects on benthic macrofauna have been done in tropical marine ecosystems. This study describes the temporal response of the water column, sediments and macrofauna to seasonal hypoxia in a semi-enclosed bay (Cienfuegos, Caribbean Sea). The Calisito site was sampled monthly from June 2010 until February 2012, yielding 21 sampling times. At each sampling event water and sediment samples were collected for measuring the abiotic variables (temperature, salinity, dissolved oxygen, nutrients, redox potential discontinuity, silt/clay and organic matter content) and macrofauna (abundance and species richness). Temperature and surface salinity followed a typical temporal pattern during the summer/rainy and the winter/dry periods. Salinity stratification occurred in the rainy period, lasting three months in 2010 and six months in 2011. The bottom water dissolved oxygen indicated hypoxic and anoxic events during the wet periods of 2010 and 2011 associated with salinity stratification, low hydrodynamics and oxidation of the accumulated organic matter. Over the study period, 817 individuals were collected and identified. Polychaetes were the dominant group in terms of abundance (57 % of total) followed by mollusks (41%). Hypoxia (and occasionally anoxia) caused strong deleterious effects on the abundance and species richness of macrofaunal communities in the study site. The most abundant polychaetes were opportunistic species with high tolerance to hypoxic conditions: Prionospio steenstrupi, Polydora sp.and Paraprionospio pinnata. Most of them colonized relatively fast once hypoxia ended. Persistent species such as Caecum pulchellum and Parvanachis obesa were present during hypoxia with fluctuating densities and apparently recover to higher abundances when normoxic conditions are re-established. Macoma tenta and Tellina consobrina colonized approximately 1-2 months later than the first polychaete peak during normoxia. Probably, the deleterious effects of hypoxia on the macrofauna were intensified by negative interspecific relationships such as competition by suitable space and predation. The recolonization of macrofauna depended possibly on local transport by currents within the bay because the connection with the Caribbean Sea is relatively limited. In summary, seasonal hypoxia in Cienfuegos Bay influences the water and sediment geochemistry and reduces both the abundance and diversity of macrofauna.


ResumenLa hipoxia es la disminución del oxígeno disuelto por debajo de 2 mg O2/L. Relativamente pocos estudios sobre la hipoxia y sus efectos en la macrofauna bentónica han sido realizados en ecosistemas marinos tropicales. Este estudio describe la respuesta temporal de la columna de agua, los sedimentos y la macrofauna a la hipoxia estacional en una bahía semicerrada en Cienfuegos, Mar Caribe. La estación de Calisito fue muestreada mensualmente de Junio 2010 a Febrero 2012, resultando en 21 eventos de muestreo. En cada oportunidad se recolectaron muestras de agua y sedimento para la medición de las variables abióticas (temperatura, salinidad, oxígeno disuelto, discontinuidad del potencial redox, contenido de limo/arcilla y materia orgánica) y macrofauna (abundancia y riqueza de especies). La temperatura y la salinidad superficial presentaron un patrón temporal típico durante los periodos de verano/ lluvia e invierno/seca. Ocurrió estratificación por salinidad en el periodo lluvioso, que duró tres meses en 2010 y seis en 2011. El oxígeno disuelto de fondo indicó eventos de hipoxia y anoxia durante los periodos lluviosos de 2010 y 2011 asociados con la estratificación de la columna de agua, la hidrodinámica lenta y la oxidación de la materia orgánica acumulada. Esto causó efectos deletéreos en la abundancia y diversidad de la macrofauna. Los poliquetos más abundantes fueron especies oportunistas con alta tolerancia a condiciones hipóxicas: Prionospio steenstrupi, Polydora sp. y Paraprionospio pinnata. La mayoría de estos colonizaron relativamente rápido una vez que terminó la hipoxia. Especies persistentes como Caecum pulchellum y Parvanachis obesa estuvieron presentes durante la hipoxia con densidades fluctuantes y aparentemente recuperaron sus abundancias cuando las condiciones normóxicas fueron re-establecidas. Macoma tenta y Tellina consobrina colonizaron 1-2 meses después que el primer pico de poliquetos durante la normoxia.Probablemente, los efectos deletéreos de la hipoxia en la macrofauna fueron intensificados por relaciones interespecíficas negativas como la competencia por espacio y la depredación. La recolonización de la macrofauna dependió probablemente del transporte local por las corrientes dentro de la bahía pues la conexión con el mar Caribe es relativamente limitada. En resumen, la hipoxia estacional en la bahía de Cienfuegos influencia la geoquímica del agua y los sedimentos y reduce la abundancia y diversidad de la macrofauna.


Asunto(s)
Animales , Oxígeno/análisis , Monitoreo del Ambiente , Biodiversidad , Invertebrados/clasificación , Estaciones del Año , Densidad de Población , Sedimentos Geológicos , Cuba , Eutrofización
6.
Rev. méd. domin ; 51(2): 15-7, abr.-jun. 1990. tab
Artículo en Español | LILACS | ID: lil-103516

RESUMEN

En 50 embarazadas con retardo del crecimiento intrauterino (RCIU) estudiadas en la Maternidad Nuestra Señora de la Altagracia durante el período marzo-agosto de 1988, realizamos monitorización electronica fetal a fin de determinar la eficacia de esta prueba en la detección de alteraciones fetales de tipo perfusional. En 37 casos la prueba fue realizada anteparto, siendo reactiva en 23 y no reactiva en 14. En 13 casos la prueba fue intraparto; de éstos resultó normal en 6 y se presentaron alteraciones en 7. En esta población los elementos más frecuentes de riesgo asociados a RCIU fueron hipertensión arterial, tabaquismo y desnutrición. Los resultados obtenidos permiten considerar que el monitoreo electrónico fetal anteparto es un recurso confiable para identificar las condiciones fetales en el RCIU, ya que detecta los productos enfermos durante el trabajo de parto, lo que permite la evolución del embarazo y del parto con riesgo mínimo de morbi-mortalidad perinatal


Asunto(s)
Embarazo , Humanos , Femenino , Retardo del Crecimiento Fetal , Monitoreo Fetal , Mortalidad Perinatal
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