RESUMEN
Most water bodies in Brazil, and in the world, are contaminated by some types of pollutants, ranging from sewage to metal/chemicals, carcinogenic products, and biodegradable detergents. Despite the extensive knowledge on their effects on fish biology and especially on gill morphology, research that concerns their impacts on gill rakers and implications in parameters such as food consumption cannot be found in the literature. Gill rakers are vital because, together with gills, they are responsible for the defense and protection of the organism and for selecting appropriate food for survival. When detergents, which can act as toxic chemical agents, get in contact with the body of the fish, they can cause severe effects that must be understood. Therefore, our study investigated ultramorphological changes in gill rakers of Astyanax altiparanae (Lambeth) caused by the exposure to biodegradable detergents. Fish were exposed to a 1 mg/L dilution of a mixture of detergents and pure water from an artesian well for 5 months. Results revealed that the first month of exposure to detergent caused dilation of chemical receptors in taste buds and the rise of a large number of orifices for mucus release among pavement cells in gill rakers, although only a small amount of mucus was found in fish exposed both to pure water and the detergent dilution. After 5 months, there was an increase in the dilation of these chemoreceptors, excess mucus on gill rakers of detergent groups, and the emergence of microbridges between microridges in pavement cells.
Asunto(s)
Characidae/anatomía & histología , Detergentes/toxicidad , Branquias/efectos de los fármacos , Branquias/ultraestructura , Contaminantes Químicos del Agua/toxicidad , Animales , Femenino , MasculinoRESUMEN
Increasing pollution levels have turned our attention to assessing lethal and sublethal effects of toxic agents using the most informative techniques possible. We must seek non-invasive or non-lethal sampling methods that represent an attractive alternative to traditional techniques of environmental assessment in fish. Detergents are amongst the most common contaminants of water bodies, and LAS (Linear Alkylbenzene Sulfonate) is one of the most used anionic surfactant on the market. Our study analyzed morphological alterations (histological and histochemical) of the scale epithelium of Prochilodus lineatus under exposure to two concentrations of LAS, 3.6mg/L and 0.36mg/L, for a period of 30 days and evaluated at 14, 21 and 30 days. In order to establish morphological analysis of the scale epithelium as a new non-lethal environmental assessment tool that is reliable and comparable to classic methods, the relative sensibility of this technique was compared to a commonly used method of environmental assessment in fish, the estimation of the effects of pollutants upon branchial morphology. Two experiments were carried out, testing animals in tanks, and in individual aquariums. Results of analyses on gill tissue show that exposure to 3.6mg/L of surfactant caused severe damage, including hyperplasia, hypertrophy and fusion at 14 days, with aneurisms at 21 and 30 days; while exposure to 0.36mg/L had lighter effects on the organ, mainly lower incidence of fusion and hyperplasia. Aditionally, scale morphology was altered severely in response to 3.6mg/L of LAS, consistently showing increased mucous and club cell production. Epithelial thickness was the most variable parameter measured. Scale epithelium sensibility has the potential to be a reliable environmental marker for fish species since it has the advantage of being less invasive when compared to traditional methods. However, more studies are required to increase the robustness of the technique before it can be generally applied.
Asunto(s)
Ácidos Alcanesulfónicos/toxicidad , Piel/efectos de los fármacos , Tensoactivos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Characiformes , Epitelio/efectos de los fármacos , Epitelio/patología , Piel/patologíaRESUMEN
The fish body is entirely covered by a thin, smooth and glandular epidermis, closely attached to the scales inserted on the dermis. The descriptive work on this tissue dates to twenty or thirty years ago, bears very little photographic record and does not focus on the scale epithelium, despite the fact that it is in direct contact with the environment. Thereupon, the present study characterizes the scale epithelium of Prochilodus lineatus, a robust species of fish. The observations show that the scale is completely covered by epithelium thicker on the proximal end of the scale, multilayered on the dorsal surface and undifferentiated on the ventral surface, and covered by mucous producing cells, mostly acid mucous. The scale is formed by plywood-like collagen matrix of collagen type III and supported by a network of elastic fibers on the ventral face. Differentiated cellular types are present, such as club cells, considered to be responsible for the release of alarm substances, which suggests possible use in environmental assessment as a non-invasive technique.
Asunto(s)
Characiformes/anatomía & histología , Characiformes/clasificación , Epitelio/anatomía & histología , Animales , Brasil , Monitoreo del Ambiente , HistocitoquímicaRESUMEN
The fish body is entirely covered by a thin, smooth and glandular epidermis, closely attached to the scales inserted on the dermis. The descriptive work on this tissue dates to twenty or thirty years ago, bears very little photographic record and does not focus on the scale epithelium, despite the fact that it is in direct contact with the environment. Thereupon, the present study characterizes the scale epithelium of Prochilodus lineatus, a robust species of fish. The observations show that the scale is completely covered by epithelium thicker on the proximal end of the scale, multilayered on the dorsal surface and undifferentiated on the ventral surface, and covered by mucous producing cells, mostly acid mucous. The scale is formed by plywood-like collagen matrix of collagen type III and supported by a network of elastic fibers on the ventral face. Differentiated cellular types are present, such as club cells, considered to be responsible for the release of alarm substances, which suggests possible use in environmental assessment as a non-invasive technique.(AU)
O corpo dos peixes é inteiramente coberto por uma epiderme fina, lisa e grandular intimamente aposta às escamas inseridas na derme. Os trabalhos descritivos sobre este assunto datam de vinte ou trinta anos atrás e possuem pouco registro fotográfico, além de não se focarem no epitélio da escama, apesar do fato de este estar em contato direto com o ambiente. Portanto, o presente estudo pretende caracterizar o epitélio das escamas de Prohilodus lineatus, uma espécie de peixe robusto. As observações mostram que a escama é completamente recoberta por epitélio, mais grosso na extremidade proximal da escama, estratificado na superfície dorsal, indiferenciado na superfície ventral e coberto por células mucosas, principalmente de muco de ácido. A escama é formada por uma matriz de colágeno de estrutura semelhante a madeira compensada de colágeno tipo III e se apóia em uma rede de fibras elásticas na superfície ventral. Tipos celulares diferenciados são presentes, como células club, consideradas responsáveis pela liberação de substâncias de alarme, o que sugere possível uso como técnica não invasiva para monitoramento ambiental.(AU)
Asunto(s)
Animales , Escamas de Animales/anatomía & histología , Epitelio/anatomía & histología , Peces/anatomía & histologíaRESUMEN
BACKGROUND: An epidemic of acute gastroenteritis occurred in Rio Branco City, Acre State, in Brazil's Amazon region in 2005. An investigation was conducted to confirm the etiology and identify possible risk factors for death. METHODS: Rio Branco municipality surveillance data for the period May to October 2005 were reviewed. In a case-control study, children who died following acute gastroenteritis were compared to age-matched controls with acute gastroenteritis who survived. Rotavirus A (RV-A) was investigated in 799 stool samples and genotyped by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: The cumulative incidence of diarrhea in children aged <5 years was 21%. A fatal outcome was significantly associated with uncovered household water storage containers. RV-A was identified in 88% of samples and G9 was the prevalent genotype (71%). CONCLUSIONS: Oral rehydration solution and boiling or chlorinating drinking water likely limited mortality. This epidemic was caused by RV-A genotype G9. After the outbreak, a rotavirus vaccine was introduced into the official childhood immunization schedule in Brazil.
Asunto(s)
Brotes de Enfermedades , Gastroenteritis/epidemiología , Infecciones por Rotavirus/epidemiología , Rotavirus/aislamiento & purificación , Enfermedad Aguda , Brasil/epidemiología , Estudios de Casos y Controles , Preescolar , Gastroenteritis/mortalidad , Gastroenteritis/virología , Genotipo , Humanos , Lactante , Factores de Riesgo , Rotavirus/genética , Infecciones por Rotavirus/mortalidad , Infecciones por Rotavirus/virologíaRESUMEN
Congonha, congonha-de-bugre e bugre são nomes populares atribuídos a várias espécies medicinais, incluindo Rudgea viburnoides (Cham.) Benth. (Rubiaceae), cujas folhas são utilizadas na medicina popular como diuréticas, hipotensoras, antireumáticas e depurativas do sangue. Esta espécie vem sendo comercializada como porangaba e utilizada em regimes de emagrecimento, substituindo Cordia ecalyculata Vell. (Boraginaceae). Neste estudo, foram determinadas as características botânicas, fisico-químicas e químicas para R. viburnoides com o objetivo de auxiliar sua identificação taxonômica e o controle de qualidade de produtos preparados com esta planta. Uma amostra referência foi coletada e submetida à caracterização macroscópica, microscópica e organoléptica, determinação de cinzas totais e umidade, prospecção fitoquímica e determinação dos perfis cromatográficos em CCD. Amostras de R. viburnoides podem ser reconhecidas pela epiderme pilosa com marcantes estrias cuticulares, estômatos paracíticos, presença de idioblastos com ráfides no mesofilo e pela configuração em arco dos tecidos vasculares da nervura de primeira ordem, caracteres ausentes em C. ecalyculata. A presença de cistólitos e canais mucilaginosos na medula diferem prontamente C. ecalyculata de R. viburnoides. A análise por CCD evidenciou a presença de flavonóides e saponinas. Amostras adquiridas no comércio e submetidas aos mesmos ensaios permitiram validar os métodos propostos e confirmaram a ampla comercialização de R. viburnoides em Minas Gerais.
Congonha, congonha-de-bugre and bugre are popular names for several medicinal plant species, including Rudgea viburnoides (Cham.) Benth. (Rubiaceae), whose leaves are widely used in popular medicine as diuretic, hypotensive, antirheumatic, and blood depurative. This species has been commercialized as porangaba, and used for diet purposes in substitution of Cordia ecalyculata Vell. (Boraginaceae). This study determines botanical, physico-chemical and chemical characteristics of R. viburnoides with the objective of providing tools for its taxonomical identification and the quality control of derived products. A reference sample was collected and submitted to macroscopical, microscopical and organoleptical characterization, total ash and water content, phytochemical screening, and TLC profile determination. Samples of Rudgea viburnoides can be easily distinguished from those of Cordia ecalyculata by the pilose epidermis with paracytic stomata, outstanding cuticularized striation, the presence of cristalliferous idioblasts, and by the arc pattern of the midvein vascular tissues. Furthermore, C. ecalyculata presents cystoliths and medullary mucilaginous channels differing from R. viburnoides. TLC analysis demostrated the presence of flavonoids and saponins. Commercially acquired samples submitted to the same assays have therefore validated the proposed methods, and confirmed the wide commercialization of R. viburnoides in the state of Minas Gerais, Brazil.
RESUMEN
SÄo apresentados os resultados de 23 exames parasitológicos de fezes coletadas com conservador MIF e analisadas pelo método preconizado por Hoffman, Pons & Janer no Laboratório de Saúde Pública/FFB/UFJF e, de 9 análises bacteriológicas da água consumida na residência de 7 escolares da EMEI "Sant'Ana Itatiaia" - Juiz de Fora - MG, segundo a metodologia empregada no Laboratório de Análise de Alimentos e Saneamento de Aguas/FFB/UFJF. O estudo foi desenvolvido nos meses de Agosto a Outubro de 1994 em escolares com idade entre 4 e 6 anos e de ambos os sexos. A percentagem das amostras de fezes positivas foi de 56,52 porcento e a de negativas de 43,48 porcento. A etiologia das enteroparasitoses de maior incidência na populaçäo estudada foi: Entamoeba coli (38,89 porcento), Ascaris lumbricoides (27,78 porcento), Trichuris trichiura (11,11 porcento), Giardia lamblia (11,11 porcento) e Entamoeba histolytica (11,11 porcento). Das amostras analisadas, 17,39 porcento revelaram a presença de mais de um parasita. Apesar de näo ter sido possível correlacionar a etiologia das enteroparasitoses com uma provável veiculaçäo hídrica das mesmas, verificou-se que 61,11 porcento das amostras de fezes examinadas revelaram a presença de protozoários e, ainda, que 60 porcento das amostras de água oriundas de outras fontes que näo o abastecimento público, foram consideradas impróprias para o consumo como bebida. Tais dados reforçam a necessidade de medidas administrativas eficientes para a implantaçäo e melhoria do saneamento básico, pois näo existe saúde sem infra-estrutura sanitária