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1.
PLoS One ; 18(6): e0283606, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37267246

RESUMO

The study was performed in the Republic of Panama. Panama has a coastline of 2,988.3 km, of which 1,700.6 km corresponds to the Pacific coast. Most of the coast is flat, and several geomorphological features characterize the Panamanian coastal sector, such as the Gulf of Montijo, which is located towards the west of the Panamanian Pacific coast in the province of Veraguas. The Gulf is a remarkable ecosystem of mangroves well preserved and internationally recognized as a Ramsar area. It represents the buffer zone of Coiba Island (Coiba National Park). Sixteen sampling stations were established along the coast to analyze the vertical and spatial variability of physical and chemical parameters (temperature, salinity, dissolved oxygen, pH, and conductivity). The quality of unexposed marine sediment was evaluated in four samples from the western sector of the Gulf of Montijo. The marine sediment samples were collected with a Dietz-LaFond Snapper dredge, between 1.5 and 3.0 m depth. Physical and chemical observations and marine sediment sampling were carried out during high tide +4 to low tide +3, in negative syzygy phase tide. The analysis of the oceanographic conditions, especially the physical and chemical properties of the water along with the longitudinal profile, showed a conservative distribution increasing gradually towards the outer region in an approximately linear way due to the dilution and mixing processes, both in the surface layer and at the bottom, and a not very developed vertical gradient, with slight stratification. The results of heavy metal analyses in marine sediments report high cadmium concentrations along the west coast, with concentrations above the limit levels of the Canadian marine sediment quality guidelines. The study area requires continuous monitoring that is representative of seasonality (dry, intermediate, and rainy periods), including a more significant number of stations since it is evidence of an affectation of the environmental quality of the marine ecosystem due to possible anthropogenic activities.


Assuntos
Ecossistema , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Canadá , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Panamá
2.
Int J Biomater ; 2022: 3606765, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387956

RESUMO

Due to their particular water absorption capacity, hydrogels are the most widely used scaffolds in biomedical studies to regenerate damaged tissue. Hydrogels can be used in tissue engineering to design scaffolds for three-dimensional cell culture, providing a novel alternative to the traditional two-dimensional cell culture as hydrogels have a three-dimensional biomimetic structure. This material property is crucial in regenerative medicine, especially for the nervous system, since it is a highly complex and delicate structure. Hydrogels can move quickly within the human body without physically disturbing the environment and possess essential biocompatible properties, as well as the ability to form a mimetic scaffold in situ. Therefore, hydrogels are perfect candidates for biomedical applications. Hydrogels represent a potential alternative to regenerating tissue lost after removing a brain tumor and/or brain injuries. This reason presents them as an exciting alternative to highly complex human physiological problems, such as injuries to the central nervous system and neurodegenerative disease.

3.
An Acad Bras Cienc ; 94(2): e20201125, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35319620

RESUMO

The effect of commercial Atrazine (ATR) on Rattus Novergicus organs was determined for a concentration of cATR of 1, 3, 13, 30, and 50 ppb. ATR was dissolved in drinking water. The rats were allowed to drink from it ad libitum for an uninterrupted period of 28 days as established by the Office of Environmental Protection protocol under the number EPA OPPTS 870.3050. In the 28 days of the test, data on the behavior of the medicated animals was recorded before the extraction of sample tissues (heart, liver, spleen, brain, and testicles) for histological analysis. A direct correlation of cATR and organ damage was found. The study showed that even for the smallest doses (1ppb), commercial ATR produced several lesions in the studied animals. The rats showed hepatic periacinar necrosis with acute coagulation, hepatocyte lipidosis, severe portal lymphocytic inflammation, coronary periarteritis, and lymphocytic meningoencephalitis for high concentrations. In the male reproductive system, testicular degeneration with mild acute tubular necrosis was observed.


Assuntos
Atrazina , Animais , Atrazina/toxicidade , Coração , Fígado , Masculino , Ratos , Baço , Testículo/patologia
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