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1.
Mar Pollut Bull ; 201: 116182, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382321

RESUMO

The present study investigated the contamination of oysters farmed in Amazonian estuaries by microplastics (MPs). A total of 120 adult oysters (Crassostrea gasar) were collected from four sites along the Mangrove Coast of Pará/Brazil: S1, S2, S3 and S4, with 30 oyster for each. Overall, 58.33 % of the oyster samples contained microplastics, with mean concentrations of 0.23 MPs/g and 1.9 MPs/ind. The concentration of microplastics varied among the four sites, where S1 and S3 had the highest values while S4 had the lowest. PA fibers were the majority of particles (91 %), followed by PS fragments (9 %). The hepatopancreas and the gonad concentrated more microplastics than the rest of the body. As an important species for aquaculture in Amazon, we recommend additional regulation to reduce human exposure to microplastics, such as the installation of depuration facilities and constant monitoring of the contamination of oysters from farms in the region.


Assuntos
Crassostrea , Poluentes Químicos da Água , Animais , Humanos , Microplásticos , Plásticos , Estuários , Aquicultura , Poluentes Químicos da Água/análise , Monitoramento Ambiental
2.
Animals (Basel) ; 13(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36978591

RESUMO

This study evaluated the follicular atresia, cell proliferation, and anti-Mullerian hormone action in Aotus nancymae and Sapajus macrocephalus during three sexual phases (follicular, luteal, and gestational). Follicular quantification and immunolocalization of Caspase-3 protein, B-cell lymphoma 2 (BCL-2), proliferating cell nuclear antigen (PCNA), and anti-Mullerian hormone (AMH) were performed. A significant difference in the quantification between preantral and antral follicles, with a progressive decrease in the antrals, was identified. Protein and hormonal markers varied significantly between follicle cell types (A. nancymae p = 0.001; S. macrocephalus, p = 0.002). Immunostaining in the preantral and antral follicles was present in all sexual phases; for Caspase-3, in granulosa cells, oocytes, and stroma; for BCL-2, in granulosa cells, oocytes, and theca; and for PCNA and AMH, in oocytes and granulosa cells. The immunostaining for Caspase-3 was more expressive in the preantral follicles (follicular phase, p < 0.05), while that for BCL-2 and PCNA was more expressive in the antral follicles of the follicular phase. The AMH was more expressive in the primary and antral follicles of nonpregnant females, in both the follicular and luteal phases. Our results contribute to understanding the ovarian follicular selection, recruitment, and degeneration of these species.

3.
Chemosphere ; 287(Pt 3): 132263, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34826937

RESUMO

Tapajós Region, is an area with intense historical artisanal and small-scale gold mining. Therefore, the core objective of this study was to evaluate the environmental status of different rivers located in this region, using biomarker endpoints in Serrasalmus rhombeus as a tool. Fish and sediment were collected from two rivers, Tropas and Crepori, affluent of Tapajós River, located inside a Federal Protection Area and in a Reference site. Mercury concentration in sediment and fish were traced, and biomarkers in gills and liver were analyzed. Results showed a clear difference between these two rivers compared to the Reference site. Fish tissues presented biomarker responses according to the site of collection. Catalase (CAT) activity was statistically higher in fish gills from Crepori, confirming the capacity of mercury interference with redox equilibrium. High levels of lipid peroxidation were also noted to contribute greatly in incidence of morphological changes in the liver and gills, suggesting that mercury bioaccumulation during continuous exposure promote biological responses in a cumulative manner, from molecules to tissues. This study also indicates adaptation in fish defense mechanisms given the conditions in the Tropas River, as well as a variation in biomarker responses to that of the Crepori river. In summary, Tapajós affluents presented high mercury levels in fish tissues leading to biomarker responses, demonstrating a hazardous signal of a long history of mercury pollution.


Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , Biomarcadores , Monitoramento Ambiental , Peixes , Ouro , Mercúrio/análise , Mercúrio/toxicidade , Mineração , Rios , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
4.
Biomed Pharmacother ; 138: 111505, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33773467

RESUMO

Doxorubicin (DOX) is an anthracycline antibiotic used in the fight against many types of cancer. Although it is quite effective for this purpose, its clinical use is limited by its severe side effects, highlighting the relevance of efforts to identify substances that act to minimize these effects. In this work, we sought to verify the ability of andiroba oil (AO) and a nanoemulsion of andiroba oil (AN) to lessen the side effects of DOX. The animals were separated into 7 groups with 6 animals each: mice treated with AO (2000 mg/kg), AN (2000 mg/kg), the antineoplastic agent DOX (40 mg/kg), AO+DOX, AN+DOX and solvent controls was used of negative control (corn oil and nanoemulsion surfactant). AO and AN were administered for 14 consecutive days orally by gavage and on the 13th day, applied DOX by intraperitoneal route (i.p.), in order to evaluate the protective potential of andiroba. The animals were euthanized on the 15th day. Hematological, biochemical, histological, and immunohistochemical parameters were analyzed. Andiroba reduced several aspects of the severity of lesions caused by DOX, decreasing hematotoxicity and the severity of histological changes in the liver and kidneys, and reducing the frequency of apoptotic cell death. In many cases, AN showed greater efficacy than AO alone, reflecting the feasibility of using this nanotechnology to improve the pharmacokinetics of lipid compounds in the body. The study sheds new light on the therapeutic benefits of andiroba and suggests new ways for investigating how the quantity and quality of lipid compounds affect exposed organisms.


Assuntos
Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Emulsões/uso terapêutico , Meliaceae , Óleos de Plantas/uso terapêutico , Animais , Emulsões/isolamento & purificação , Emulsões/farmacologia , Feminino , Injeções Intraperitoneais , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/farmacologia , Baço/efeitos dos fármacos , Baço/patologia
5.
Anim Reprod Sci ; 227: 106732, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33690051

RESUMO

Studies related to morpho-physiology improve the understanding of biological mechanisms in non-human primates (NHP), contributing to research in several areas, especially those of assisted reproduction and biomedicine. The genera Aotus and Sapajus are important considerations in conducting studies related to reproductive biology and biomedical research, where animals of these genera can serve as models for species with vulnerable conservation status. The reproductive functions of animals of these genera can be used in conducting studies with other NHP species, for which biological material is difficult to access. The aim in conducting the current review was to compile the scientific literature on the biology and reproductive aspects of these two genera, to provide a for a greater understanding of these topics. In addition, a systematic review of literature allows for efficient access relevant information from an extended timeframe collated in a single document. There was, therefore, a systematic search for keywords based on reproductive studies with animals in these genera conducted, and 58 articles, 12 books, and three academic theses were subsequently selected. Even though there have been advances in knowledge of the reproductive biology of animals from these genera that have occurred in recent decades, especially research conducted when these NHP were in captivity, a wide variety of areas remain to be studied so that the understanding of reproduction in these NHP can be enhanced and the knowledge gained from these studies utilized for greater understanding of reproduction of NHP in general.


Assuntos
Aotidae , Reprodução/fisiologia , Sapajus , Animais , Conservação dos Recursos Naturais , Especificidade da Espécie
7.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 53(3): 251-259, 2016. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-875209

RESUMO

A functional understanding of the epididymis makes it possible to increase a species' fertility, since it facilitates the preservation of gametes for use in assisted reproduction techniques. This study analyzed the histological features of the different regions of the epididymis of the Pecari tajacu and the associated pathologies found in the spermatozoa present in this organ. After an orchiectomy surgery to remove the testicles and epididymis obtained from eight adult animals bred in captivity, fixation and histological processing of samples were carried out. The presence of pseudostratified columnar epithelium with stereocilia was observed in all regions of the epididymis (caput, corpus and caudal). Similarities were noted between the average height of the corpus and caudal epithelium, which differed from that found at the caput (1- proximal: region associated with the efferent ducts; 2- distal: region associated with corpus epididymis). It was also observed that the proximal caput presents a smaller average of the tubules diameter compared to other portions of the epididymis. Regarding pathologies of the spermatozoa, thirteen different types of morphological modifications were observed. Underdeveloped spermatozoa and detached heads were most frequently encountered along the epididymis of the collared peccaries. This study is a pioneer in the area and its data will serve as a basis for comparative research on the reproductive biology of artiodactyls, thus contributing to their conservation and reproduction.(AU)


O entendimento funcional do epidídimo possibilita o aumento da fertilidade de uma espécie, pois torna possível a preservação de gametas para o uso em técnicas de reprodução assistida. Este trabalho estudou os aspectos histológicos das diferentes regiões do epidídimo de Pecari tajacu, bem como as patologias associadas encontradas nos espermatozoides presentes nesse órgão. Após procedimento cirúrgico de orquiectomia, para remoção dos testículos e epidídimos, obtidos de oito animais adultos nascidos em cativeiro, realizou-se a fixação e o processamento histológico das amostras. Constatou-se em todas as regiões do epidídimo (cabeça, corpo e cauda) a presença de epitélio pseudoestratificado colunar com estereocílios. Foram observadas semelhanças entre a altura média do epitélio do corpo e da cauda, a qual era diferente da encontrada na cabeça (1- proximal: região associada aos ductos eferentes; 2- distal: região associada ao corpo do epidídimo). Foi verificado que a cabeça proximal apresenta a média de diâmetro dos túbulos menor em relação às demais porções do epidídimo. Em relação às patologias dos espermatozoides, constataram-se treze tipos diferentes de alterações morfológicas. Os espermatozoides subdesenvolvidos e cabeças soltas foram as mais frequentes ao longo do epidídimo de catitus. Os dados deste trabalho são pioneiros, e servirão como base para pesquisas comparativas sobre a biologia reprodutiva dos artiodátilos, contribuindo para a sua conservação e produção.(AU)


Assuntos
Animais , Artiodáctilos , Epididimo/anatomia & histologia , Epididimo/fisiologia , Espermatozoides/patologia , Técnicas Histológicas/veterinária
8.
Acta sci., Biol. sci ; 37(1): 113-121, jan.- mar. 2015. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-848007

RESUMO

In this study, histological, ultrastructural, and immunohistochemical observations of the gill tissue of two fish species (Plagioscion squamosissimus and Lithodoras dorsalis) were used as biomarkers to assess the ecological conditions of an estuary in the Amazon delta, by relating the health status of the fishes to environmental quality. The gill tissue was analyzed both qualitatively and semi-quantitatively. Marked differences in the type and severity of lesions were verified between species and among study sites. A variety of severe damages were confirmed histologically in specimens from the two impacted areas (B and C), including aneurysms, epithelial lifting, and intense hyperplasia. Electron microscopy and immunohistochemical analyses also revealed injuries in the gill tissue of specimens from these two areas. While, on area A only few specimens showed mild changes in gill tissues and rare marking of apoptosis. These results confirm the urgent need for the more effective control of the discharge of pollutants into the estuary as well as more effective urban planning, given the close proximity of a major industrial complex to residential areas.


Neste estudo foram utilizados biomarcadores histológicos, ultraestruturais e imunohistoquímicos em tecidos brânquiais de duas espécies de peixes, Plagioscion squamosissimus e Lithodoras dorsalis, para avaliar a situação ecológica em um estuário amazônico relacionando a saúde do peixe com a qualidade ambiental. O tecido branquial foi analisado qualitativamente e semiquantitativamente. Foram verificadas diferenças entre as espécies selecionadas e as áreas de estudo, no que se refere ao tipo e severidade das lesões no tecido branquial. Foi detectada uma variedade de alterações histopatológicas severas somente nos peixes capturados nas áreas B e C, tais como: Aneurisma, elevação epitelial e intensa hiperplasia. As análises de microscopia eletrônica e de imunohistoquímica confirmaram danos mais prejudiciais nas brânquias apenas nestas áreas de estudo. Enquanto que na área A poucos peixes apresentaram alterações leves nos tecidos e pouca marcação de apoptose. Estes resultados confirmam a necessidade de um efetivo controle dos dejetos de poluentes assim como um planejamento urbano eficaz nesta região, uma vez que esta área possui um complexo industrial importante próximo à área urbana.


Assuntos
Peixes , Brânquias , Histologia , Marcação In Situ das Extremidades Cortadas , Efluentes Industriais
9.
Acta amaz ; 43(1): 99-103, mar. 2013. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455105

RESUMO

Biological studies are necessary for the management of wildlife in captivity, and knowledge of reproduction is one of the important features for increasing production. The objective of the research was to determine the age at which male collared peccaries reach puberty. Testicular samples of 15 animals, aged 7 to 16 months, distributed into five groups (G1, G2, G3, G4 and G5) were used. The testes showed considerably increased weight, length and width (p < 0.05) from G1 to G3, whereas, from this group onward, the development of this organ was slower. There was positive correlation (p < 0.001) between the following testicular parameters: weight and length (r = 0.97), weight and width (r = 0.88), length and width (r = 0.92). Regarding the diameter of seminiferous tubules, an increase was observed (p < 0.05) from G1 to G4. The total number of spermatogenic cells increased significantly (p < 0.05) until G3 and then it stabilized. There was also positive correlation between testis weight and tubular diameter (r = 0.99, p < 0.001), and testis weight and spermatogenic cells (r = 0.98, p < 0.001). The number of Sertoli cells decreased significantly (p < 0.05) from G1, when they were undifferentiated as support cells, to G5, when they occurred together with the complete line of spermatic cells. The results demonstrate that the reproductive development of peccaries can be classified into the following stages: impuberty (G1, 7-8 months); pre-pubertal (G2, 9-10 months); pubertal (G3, 11-12 months); post-pubertal 1 (G4, 13-14 months); and post-pubertal 2 (G5, 15-16 months). Based on the histological analyses, puberty in the male collared peccary was determined to occur between 11 and 12 months of age.


Estudos biológicos são necessários para o manejo da vida silvestre em cativeiro, e o conhecimento da reprodução é um dos aspectos importantes para o aumento da produção. Esta pesquisa teve como objetivo determinar a idade da puberdade do cateto macho. Foram utilizadas amostras testiculares de 15 animais, entre 7 a 16 meses, distribuídos em cinco grupos (G1, G2, G3, G4 e G5). Os testículos aumentaram no peso, comprimento e largura consideravelmente (p < 0,05) do G1 ao G3, enquanto que, a partir deste grupo, o desenvolvimento desse órgão foi mais lento. Houve correlação positiva (p < 0,001) entre os seguintes parâmetros testiculares: peso e comprimento (r = 0,97), peso e largura (r = 0,88), comprimento e largura (r = 0,92). Com relação ao diâmetro tubular, observou-se um aumento (p < 0,05) do G1 ao G4. A quantidade total de células espermatogênicas aumentou significativamente (p < 0,05) até o G3, e se estabilizou a partir deste grupo. Houve correlação positiva entre o peso testicular e o diâmetro tubular (r = 0,99, p < 0,001), bem como o peso testicular e as células espermatogênicas (r = 0,98, p < 0,001). A quantidade de células de Sertoli reduziu significativamente (p < 0,05) do G1, onde se encontravam indiferenciadas como células de suporte, até G5, onde foram observadas juntamente com todas as células da linhagem espermática. Estes resultados demonstraram que as fases do desenvolvimento reprodutivo de catetos podem ser classificadas em: impúbere (G1, 7-8 meses), pré-púbere (G2, 9-10 meses), púbere (G3, 11-12 meses), pós-púbere 1 (G4, 13-14 meses) e pós-púbere 2 (G5, 15-16 meses). Com base na análise histológica, a puberdade dos catetos machos ocorre entre 11 e 12 meses de idade.


Assuntos
Masculino , Animais , Artiodáctilos/fisiologia , Espermatogênese , Maturidade Sexual , Testículo/anatomia & histologia , Pesos e Medidas Corporais/veterinária
10.
Rev Biol Trop ; 60(1): 437-45, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22458237

RESUMO

The sustainability and production of collared peccary (Pecari tajacu) has been studied in the last few years; however, further information on its reproduction is necessary for breeding systems success. Understanding folliculogenesis aspects will contribute to effective reproductive biotechniques, which are useful in the preservation and production of wildlife. The aim of this study was-to evaluate the ovarian folliculogenesis in collared peccary. Ovaries from six adult females of collared peccary were obtained through ovariectomy and analyzed. These were fixed in aqueous Bouin's solution and sectioned into 7 microm slices, stained with hematoxilin-eosin and analyzed by light microscopy. The number of pre-antral and antral follicles per ovary was estimated using the Fractionator Method. The follicles, oocytes and oocyte nuclei were measured using an ocular micrometer. Results showed that the length, width, thickness, weight, and the gross anatomy of the right and left ovaries were not significantly different. However, the mean number of corpora lutea was different between the phases of the estrous cycle (p<0.05), with the highest mean in the luteal phase. Primordial follicles were found in the cortex; the oocytes were enveloped by a single layer of flattened follicular cells. In the primary follicles, proliferation of the follicular cells gave rise to cuboidal cells (granulosa cells). The secondary follicle was characterized by two or more concentric layers of cuboidal cells (granulosa), beginning of antrum formation, and the presence of pellucid zone and theca cells. Antral follicles were characterized by a central cavity (antrum), the presence of cumulus oophorus and theca layers (interna and externa). In the right ovary, the values of the primordial and primary follicles were similar, but significantly different from the secondary ones (p<0.05). In the left ovary, significant differences were observed between all follicles in the follicular phase (p<0.05); the mean number of primordial and primary follicles was similar in the luteal phase. The mean number of pre-antral follicles and antral follicles in the follicular phase was higher in the left ovary (p<0.05). The mean number of antral follicles in the luteal phase was similar in both ovaries. We also found significant differences in mean diameter of preantral follicles, oocyte, granulosa layer and oocyte nucleus during the estrous cycle. In the antral follicles a significant difference was observed only in follicular diameter (p<0.05). The predominance of active primordial and primary follicles was found in both phases; otherwise the secondary follicles and antral follicles showed a high degree of degeneration. The results obtained in the present work will strengthen the development of biotechnology programs to improve the productive potential and conservation of the collared peccary.


Assuntos
Artiodáctilos/anatomia & histologia , Folículo Ovariano/anatomia & histologia , Animais , Artiodáctilos/fisiologia , Ciclo Estral/fisiologia , Feminino , Fase Folicular/fisiologia , Fase Luteal/fisiologia , Folículo Ovariano/fisiologia
11.
Acta sci., Biol. sci ; 32(1): 93-99, jan.-mar.2010. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460624

RESUMO

This work analyzes the morphological alterations in Brachyplatystoma rousseauxii gills and evaluates whether this species can be considered an environmental monitoring biomarker of Guajará Bay. Sampling was carried out in four areas around Belém, Brazil, in four annual periods: dry/wet season, wet season, wet/dry season and dry season. Water pH, temperature and suspended material were evaluated. A total of 36 specimens were collected. The second right gill arch of each animal was removed and immediately fixed and processed for histopathology analysis with light microscopy. The physicochemical analysis of the water during the study period showed slight acidity, temperature and material in suspension within normal levels. Histopathological analysis of the gills from 14 individuals from area I presented no alterations, and only 2 individuals from this area presented some significant type of alteration. In contrast, all individuals captured in areas II, III, and IV presented at least one of the following alterations: aneurism-like alterations, epithelial elevation, infiltration, cell proliferation and cell hypertrophy. Based on the gill histopathological analysis, this organ is considered a good biomarker and the native species B. rousseauxii could be used as a bioindicator for environmental monitoring.


O objetivo deste trabalho foi analisar as alterações morfológicas branquiais em Brachyplatystoma rousseauxii e verificar se esta espécie pode ser considerada como indicador biológico para o monitoramento ambiental da baía do Guajará. As coletas aconteceram em quatro áreas ao redor da cidade de Belém: I (controle), II, III e IV (forte influência antrópica), nos quatro períodos anuais: estação seco/chuvoso, estação chuvoso, estação chuvoso/seco e estação seco. Nesses períodos foram medidos pH, temperatura e material em suspensão. Foram capturados 36 exemplares. O segundo arco branquial direito de cada animal foi retirado, imediatamente fixado e processado para análise histopatológica. A análise físico-química da água revelou pH levemente ácido, a temperatura e o material em suspensão se encontravam nos parâmetros de normalidade. As análises histopatológicas das brânquias de 14 animais da área I não apresentaram alterações branquiais e somente dois revelaram algum tipo de alteração. Todos os indivíduos capturados nas áreas II, III e IV apresentaram pelo menos uma das seguintes alterações: aneurisma, elevação epitelial, infiltração, proliferação celular, fusão lamelar e hipertrofia celular. De acordo com as análises histopatológicas branquiais, este órgão é considerado como um bom biomarcador e a espécie nativa B. rousseauxii pode ser utilizada como bioindicador no monitoramento ambiental.


Assuntos
Animais , Monitoramento Ambiental , Peixes
12.
Rio de Janeiro; s.n; set. 2002. xv,110 p. ilus.
Tese em Português | LILACS | ID: lil-349678

RESUMO

A malária humana tem sido considerada um grave problema de saúde no mundo. Os estudos de interação envolvendo vetores do Novo Mundo e Plasmodium humano ainda são muito limitados. Análises estruturais e ultraestruturais foram realizadas com o objetivo de conhecer o aspecto normal e o percurso do P. vivax, no intestino médio do A. aquasalis. Por meio de técnicas histológicas, de microscopias eletrônicas de varredura e transmissão e a laser confocal foi descrita a organização dos tipos celulares, a ultraestrutura das células, a cinética das modificações do intestino quando alimentados e a análise do estabelecimento da infecção pelo P. vivax acompanhando o ciclo no A. aquasalis. Desse modo, observamos, em ambas as regiões do intestino médio, uma heterogeneidade celular quanto à afinidade pelos corantes, revelada principalmente pela presença de componenetes ácidos. O aspecto externo e o interno do intestino médio apresentaram uma regularidade de superfície. Vesículas de secreção foram encontradas com freqüência nas células da região torácica; a região abdominal, além de revelar células com vesículas, também mostrou com freqüência organelas relacionadas com a síntese de proteínas. O aspecto citoquímico das superfícies apical e basal não só demonstrou a presença de componenetes aniônicos, bem como a de carboidratos. A infecção por P. vivax foi determinada pela presença dos oocistos, que foram considerados jovens quando demonstraram centro esporoblastóide, esporozoítos organizados e parede irregular; oocistos maduros apresentaram superfície lisa e esporozoítos desorganizados no seu interior. Visualizamos a saída dos esporozoítos do oocisto, a liberação para a hemocele e a invasão nas células secretoras da glândula salivar do A. aquasalis, que não ocorreram sincronicamente, após a infecção. Por meio da microscopia a laser confocal, observamos oocineto no epitélio e preferencialmente no espaço intercelulocorrendo pouca modificação nas microvilosidades. O oocineto migra para a porção basal do epitélio, onde se modifica em oocisto. Este trabalho compreende o início do estudo da interação utilizando Plasmodium humano e vetores do Novo Mundo, podendo, portanto, ser considerado como indutor para novas pesquisas neste modelo.


Assuntos
Animais , Anopheles , Intestinos , Malária , Oocistos/ultraestrutura , Plasmodium vivax , Microscopia Eletrônica/métodos , Microscopia Confocal
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