ABSTRACT
The Muscovy duck is a commercially important bird on the island of Marajó usually raised in a peculiar system that includes supplying fish viscera to the birds under semi-extensive farming conditions. This enables a risk of contamination and losses in the production of these birds, resulting from injuries caused by helminth infections, especially nematodes. The objective of this study was to evaluate the histopathological changes caused by nematodes of the genera: Eucoleus, Anisakis and Contracaecum. Thirty-three ducks with lesions in the esophagus and ventricle were analyzed. Histopathological exams showed a mild inflammatory infiltrate in the submucosa of the esophagus caused by the fixation of E. contortus and third stage larvae of Anisakis sp., and we recorded third stage larvae of Contracaecum sp. parasitizing the ventricle, this being the first record of this parasite in ducks in Brazil.(AU)
O pato doméstico é uma ave amplamente comercializada na Ilha de Marajó, com um peculiar manejo que inclui a oferta de vísceras de peixes aos animais em criações semiextensivas, propiciando, assim, risco de contaminação e perdas na produção dessas aves decorrentes de lesões oriundas de infecções por helmintos, especialmente os nematódeos. Nesse sentido, objetivou-se avaliar as alterações histopatológicas causadas por nematódeos dos gêneros: Eucoleus, Anisakis e Contracaecum. Foram analisados 33 patos, e três exemplares apresentaram lesões no esôfago e no ventrículo. Exames histopatológicos demonstraram discreto infiltrado inflamatório na submucosa do esôfago ocasionado pela fixação de E. contortus e larvas de terceiro estágio de Anisakis sp., bem como foram registradas larvas de terceiro estágio de Contracaecum sp. parasitando o ventrículo, sendo esse o primeiro registro desse parasito em patos no Brasil.(AU)
Subject(s)
Animals , Ducks/injuries , Ducks/parasitology , Esophagus/injuries , Helminths/isolation & purification , Nematoda/isolation & purification , Parasitic Diseases/complications , BrazilABSTRACT
Some physical properties of nanogel particles formed by chitosan ionically cross-linked by tripolyphosphate (TPP) have been studied. Electrokinetic properties and colloidal stability were analyzed as a function of pH and ionic strength of the medium. Chitosan particles showed volume phase transitions (swelling/shrinking processes) when the physicochemical conditions of the medium were changed. Experimental data were mainly obtained by electrophoretic mobility measurements and by photon correlation spectroscopy and static light scattering techniques. Chitosan chains possess glucosamine groups that can be deprotonated if the pH increases. Therefore, modification of pH from acid to basic values caused a deswelling process based on a reduction of the intramolecular electric repulsions inside the particle mesh. Electrophoretic mobility data helped to corroborate the above electrical mechanism as responsible for the size changes. Additionally, at those pH values around the isoelectric point of the chitosan-TPP particles, the system became colloidally unstable. Ionic strength variations also induced important structural changes. In this case, the presence of KCl at low and moderate concentrations provoked swelling, which rapidly turned on particle disintegration due to the weakness of chitosan-TPP ionic interactions. These last results were in good agreement with the predictions of gel swelling theory by salt in partially ionized networks.
Subject(s)
Chitosan/chemistry , Nanostructures/chemistry , Chemical Phenomena , Chemistry, Physical , Electrochemistry , Static Electricity , Time FactorsABSTRACT
We report on a three-generation Brazilian family with seven patients affected with non-progressive high-frequency sensorineural hearing loss with no associated anomalies first noted in early infancy. To our knowledge this is the first report on this autosomal-dominant condition. Clinical, audiological, and genetic aspects are discussed.
Subject(s)
Genes, Dominant , Hearing Loss, Sensorineural/genetics , Adolescent , Adult , Aged , Audiometry , Brazil , Child, Preschool , Family Health , Female , Hearing Loss, Sensorineural/pathology , Humans , Infant , Male , Middle Aged , PedigreeABSTRACT
Ultrastructural studies of the interaction between T. cruzi clone Dm28c and heart muscle cells (HMC) showed that in the initial phase of the cell recognition process several parasites could be found attached to a focal point on the surface of the host cell. Immediately following this phase, two or more parasites could be detected inside the same endocytic vacuole by electron spectroscopic imaging (ESI).
