Crescimento pulmonar compensatório (CPC): massa corpórea, conteúdo protéico e massa pulmonares em ratos subnutridos trilobectomizados

OBJETIVO:Avaliar o comportamento bioquímico do CPC após trilobectomia no rato adulto jovem subnutrido. MÉTODOS: Foram utilizados 137 ratos Wistar, machos, subnutridos pela oferta de 33% da ingestão diária normal na fase de adaptação e durante o experimento, distribuídos por sorteio, em 9 grupos experimentais, submetidos a três tratamentos (Controle, Toracotomia, Trilobectomia) e sacrificados em três momentos (7, 30 e 90 dias). Na Trilobectomia foram extirpados os lobos médio, acessório e caudal direitos, que representavam 55% do tecido pulmonar. Estudou-se os seguintes atributos e variáveis: massa corpórea e pulmonar, relação entre massa pulmonar e corpórea e conteúdos protéicos pulmonares. RESULTADOS: No lobo cranial e no pulmão esquerdo, tanto a massa quanto os conteúdos protéicos, nos trilobectomizados, foram maiores em todos os momentos do estudo quando comparados aos demais, sendo este aumento suficiente para compensar a perda dos três lobos. Os conteúdos protéicos do lobo cranial e do pulmão esquerdo, nos trilobectomizados, tiveram o mesmo comportamento da massa pulmonar, mas este aumento não foi suficiente para compensar a perda dos três lobos. CONCLUSÕES: Nos ratos adultos subnutridos trilobectomizados ocorre CPC. A recuperação da massa pulmonar é total, mas o conteúdo protéico pulmonar apesar de aumentar, não chega aos valores dos ratos não trilobectomizados.

Compensatory lung growth: protein, DNA and RNA lung contents in undernourished trilobectomized rats

OBJETIVO: demonstrar se ocorre crescimento pulmonar compensatório (CPC) representado pelos conteúdos de proteínas, DNA e RNA no rato adulto jovem, subnutrido, submetido à trilobectomia pulmonar. MÉTODOS: Utilizamos 137 ratos Wistar, machos, distribuídos por sorteio, em 9 grupos, submetidos a três tratamentos (controle, toracotomia, trilobectomia), sacrificados em três momentos (7, 30 e 90 dias). Na trilobectomia foram extirpados os lobos médio, acessório e caudal direitos. Variáveis estudadas: conteúdos pulmonares de proteínas, DNA e RNA. RESULTADOS: No lobo cranial e pulmão esquerdo o conteúdo protéico foi maior nos trilobectomizados. Ocorreu CPC insuficiente para suprir a perda desta variável, sendo menor nos pulmões dos trilobectomizados. O incremento nos conteúdos de DNA do lobo cranial e pulmão esquerdo dos trilobectomizados foram suficientes para compensar a perda desta variável, resultando num conteúdo de DNA dos pulmões semelhante aos controle. O conteúdo de RNA, nos trilobectomizados, foi maior no lobo cranial e pulmão esquerdo, com maior eficiência no primeiro, insuficiente para que se aproximassem aos obtidos nos demais grupos, ficando menores. CONCLUSÃO: Nos trilobectomizados ocorreu CPC, provavelmente com hiperplasia celular e pouca hipertrofia, devido a grande compensação do DNA e pequena do RNA. Esta foi a grande diferença quando comparamos este resultado ao obtido com animais nutridos, que apresentavam hipertrofia pronunciada.

Implante lobar autólogo pós pneumonectomia: modelo experimental em cães

OBJETIVO: Estudar no implante lobar autólogo a eficiência da anastomose brônquica simples, a perfusão pulmonar e as complicações devido a desproporção doador/receptor. MÉTODOS: Estudou-se 15 cães submetidos à pneumonectomia esquerda, e reimplante do lobo caudal. Estudou-se a perfusão pulmonar e a anastomose brônquica, respectivamente, por cintilografia e por broncografia. O sacrifício ocorreu aproximadamente 200 dias após a cirurgia para o estudo das anastomoses e medidas de volumes e pesos pulmonares. RESULTADOS: Quatro cães foram a óbito, um por deiscência precoce de anastomose brônquica, 1 com infecção e outros 2 por infarto pulmonar devido a oclusão da veia pulmonar no local da anastomose. A perfusão relativa do pulmão direito e esquerdo foram em média respectivamente 72,7% e 27,3%. A broncografia não mostrou nem estenose nem outras alterações na anastomose brônquica. No momento do sacrifício o lobo caudal ocupava totalmente a cavidade pleural sem que houvesse evidentes desvios do mediastino. CONCLUSÕES: O estudo mostrou que a sutura brônquica término-terminal desprotegida não levou a complicações anastomóticas. Não houve complicações pelo fato do lobo implantado ter ocupado somente metade da cavidade pleural. As complicações mais importantes foram o infarto pulmonar e deiscência total da parede torácica. Tanto a broncografia como a cintilografia se mostraram eficientes respectivamente, para o estudo da anastomose brônquica e da perfusão relativa do pulmão funcionante in vivo.

Topografia da artéria hepática no fígado de capivara (Hydrochaerus hydrochaeris)

A distribuição dos ramos da artéria hepática, no fígado, foi estudada em 30 fígados de capivara (Hydrochaerus hydrochaeris) mediante injeção arterial com látex natural corado, fixação em formol a 10%, dissecção pela face visceral e esquematização. A lobação do fígado, nestes animais, é semelhante à do suíno, permitindo identificar os lobos lateral direito, medial direito, quadrado, medial esquerdo, lateral esquerdo e caudado (processos caudado e papilar). A artéria hepática divide-se mais freqüentemente (73,3%) nos ramos direito e esquerdo e, em menor número de preparações (26,6%), trifurca-se nos ramos direito, intermédio e esquerdo. Esses vasos alcançam, sob diferentes arranjos, os lobos do fígado.

Anatomicosurgical arterial segmentation of the cat lungs (Felis catus domesticus, L., 1758)

O objetivo desta pesquisa foi estabelecer os segmentos anátomo-cirúrgicos arteriais, através da lobação e ramificação intralobar arterial, em pulmões de gato. Após a dissecção de vinte pulmões, notou-se que a artéria pulmonar direita geralmente emite um ramo para o lobo cranial e um ramo para o lobo médio, sendo originados juntos em um tronco. Um grande ramo irriga o lobo caudal na maioria dos casos. Dois ramos com origem comum no ramo arterial do lobo caudal irrigam o lobo acessório. A artéria pulmonar esquerda origina um tronco que, na maioria dos casos, emite um ramo para a porção cranial e um ramo para a porção caudal do lobo cranial esquerdo. Pode-se concluir que o pulmão direito é formado por quatro e o esquerdo por dois lobos, ocorrendo variações na ramificação arterial pulmonar.

Aspectos morfológicos do fígado do cervo-do-pantanal (Blastocerus dichotomus)

A descrição macroscópica do fígado do Cervo do Pantanal foi realizada com ênfase à forma, localização, meios de fixação, disposição e lobação. Foram utilizados os órgãos de animais provenientes do Projeto Cervo do Pantanal de Porto Primavera, que morreram no período de quarentena, mediante inspeção visual e posterior dissecação. Foi constatado que o fígado do Cervo do Pantanal localiza-se na porção cranial da cavidade abdominal, à direita do plano mediano, possui coloração castanho-avermelhado e apresenta duas faces, quatro bordas, quatro lobos e cinco ligamentos. A principal característica que o difere dos fígados dos outros ruminantes é a ausência de vesícula biliar.

Structure of human uropepsin at 2.45 angstrom resolution

The molecular structure of human uropepsin, an aspartic proteinase from the urine produced in the form of pepsinogen A in the gastric mucosa, has been determined by molecular replacement using human pepsin as the search model. Crystals belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 50.99, b = 75.56, c = 89.90 Angstrom. Crystallographic refinement led to an R factor of 0.161 at 2.45 Angstrom resolution. The positions of 2437 non-H protein atoms in 326 residues have been determined and the model contains 143 water molecules. The structure is bilobal, consisting of two predominantly beta -sheet lobes which, as observed in other aspartic proteinases, are related by a pseudo-twofold axis. A model of the uropepsin-pepstatin complex has been constructed based on the high-resolution crystal structure of pepsin complexed with pepstatin.

Placentation in the rock cavy, Kerodon rupestris (Wied)

Rock cavies are rodents found in the semi-arid caatinga of Brazil. We studied the structure of the rock cavy placenta by light and transmission electron microscopy. The exchange area of the labyrinth was organized in lobes separated by interlobular areas. The interhaemal barrier was syncytial haemomonochorial. The syncytiotrophoblast had recesses in the basal membrane and some invaginations of the apical membrane, but transtrophoblastic channels could not be found. The interlobular regions comprised syncytiotrophoblast, enclosing maternal venous blood channels, and cytotrophoblast. There was a prominent subplacenta composed of cytotrophoblast and syncytiotrophoblast. Microvilli projected into spaces between the cytotrophoblasts and into lacunae within the syncytiotrophoblast. The yolk sac epithelium exhibited coated pits, endocytotic vesicles and larger vacuoles, consistent with a role in protein uptake from the uterine lumen. Tight junctions between these cells provided a barrier to diffusion by the intercellular route. The reproductive biology of the rock cavy differs from other members of the family, including the guinea pig, but the architecture of the placenta remains remarkably constant. (c) 2004 Elsevier Ltd. All rights reserved.

Study of lobation and vascularization of the lungs of wild boar (Sus scrofa)

The purpose of this study was to describe the anatomy of the lungs of wild boars for comparison with those of domestic swine. It was found that the right lung of the wild boar is divided into four lobes: cranial, median, caudal and accessory, whereas the left lung is divided into two lobes: cranial and caudal. In 93.4% of the cases, right pulmonary artery separates into the ascendant, descendant, median, accessory and caudal branches. In 73.3% of the cases, left pulmonary artery separates most frequently to form three branches to the cranial lobe, whereas the median lobe is generally supplied by only one arterial branch. There is a single pattern of bronchial distribution: in the right lung a tracheal bronchus leads to the cranial lobe, where it separates into the cranial and caudal bronchi and there are also bronchi to the median, caudal and accessory lobes. In the left lung, the large bronchus separates to form two branches, one of which further separates to form two branches to the cranial lobe whereas the other forms a single branch to the caudal lobe.

Hemiodus jatuarana, a new species of Hemiodontidae from the rio Trombetas, Amazon Basin, Brazil (Teleostei, Characiformes)

Hemiodus jatuarana, a new species of the Hemiodontidae from Oriximina, rio Trombetas, Amazon Basin, Brazil, is described. The new species can be readily distinguished from its congeners by the presence of a horizontally elongated dark spot on the caudal peduncle, and by the absence of any other dark pigmentation pattern on the body. Hemiodus jatuarana is readily separated from H. immaculatus, another species without dark pigmentation on the body, by having 25 - 27 epibranchial and 36 - 37 ceratobranchial gill rakers on the first branchial arch, and caudal-fin lobes without longitudinal stripes, vs. 14 - 16 and 21 - 25 gill rakers, and a conspicuous longitudinal stripe on each caudalfin lobe in H. immaculatus. The new species is only known from its type-locality, where it cooccurs with H. immaculatus.

Anindobothrium n. gen. (Eucestoda : Tetraphyllidea) inhabiting marine and freshwater potamotrygonid stingrays

Anindobothrium n. gen. is proposed to accommodate Caulobothrium anacolum inhabiting Himanturu schmardae from Colombia, and 2 new species, one inhabiting Potamotrygon orbigny in Brazil and the other inhabiting Paratrygon aereiba in Venezuela. Members of the new genus resemble members of Pararhinebothroides, Rhinebothroides, and Anthocephalum by having bothridia with poorly differentiated apical suckers and vasa deferentia expanded into external seminal vesicles. It further resembles Pararhinebothroides, Rhinebothroides, and Anthocephalum cairae by having vas deferens inserted near the poral rather than aporal end of the cirrus sac. The 3 species assigned to the new genus form an apparent monophyletic group, based on the possession of 3 putative synapomorphies: (1) genital pores in the anterior 1/4 of the proglottid, a trait that is unusual, but not unique, among phyllobothriids; (2) anteroventral ovarian lobes converging to the center of the proglottid, a character not previously reported for phyllobothriids; and (3) ovarian lobes comprising a loose network of digitiform processes.

Molecular model for the binary complex of uropepsin and pepstatin

The three-dimensional structure of human uropepsin complexed with pepstatin has been modelled using human pepsin as a template. Uropepsin is an aspartic proteinase from the urine, produced in the form of pepsinogen A in the gastric mucosa. The structure is bilobal, consisting of two predominantly beta -sheet lobes which, as observed in other aspartic proteinases, are related by a pseudo twofold axis. A structural comparison between binary complexes of pepsin:pepstatin and uropepsin:pepstatin is discussed. (C) 2001 Academic Press.

Vascular organization of the hystricomorph placenta: a comparative study in the Agouti, capybara, guinea pig, paca and rock cavy

The placental vasculature of five hystricomorph rodents was examined by latex injection of the blood vessels, immunohistochemistry and scanning electron microscopy of vessel casts. The pattern of branching of the vessels is described at the level of fine structure. The placenta is divided into lobes separated by interlobular trophoblast. Fetal arteries course through the interlobular areas and give rise to capillaries from which blood drains into veins at the centre of the lobes. Maternal blood reaches the placenta through spiral arteries that pass around the perimeter of the subplacenta. They supply large maternal blood sinuses, lined by trophoblast, which run through the interlobular areas and into the centre of the lobes. Here they supply fine channels that run parallel to the fetal capillaries, so that maternal blood flows from the centre of the lobe to the periphery. This arrangement provides the morphological basis for countercurrent exchange. The maternal channels of the labyrinth drain into spaces formed by the latticework of the interlobular trophoblast and thence through venous lacunae to a basal venous lacunar ring. The subplacenta is supplied by a single fetal artery. The vessels within the subplacenta pursue a tortuous course with dilatations and constrictions as in an endocrine gland. (C) 2003 Elsevier Ltd. All rights reserved.

Placentation in the paca (Agouti paca L)

Background: the paca is a South American rodent with potential as a commercial food animal. We examined paca placenta as part of a wider effort to understand the reproductive biology of this species.Methods: Thirteen specimens between midgestation and term of pregnancy were studied by light and transmission electron microscopy.Results: the placenta is divided into several lobes separated by interlobular trophoblast. Maternal arterial channels and fetal veins are found at the centre of each lobe. In the labyrinth, maternal blood flows through trophoblast-lined lacunae in close proximity to the fetal capillaries. The interhaemal barrier is of the haemomonochorial type with a single layer of syncytiotrophoblast. Caveolae occur in the apical membrane of the syncytiotrophoblast and recesses in the basal membrane, but there is no evidence of transtrophoblastic channels. The interlobular areas consist of cords of syncytiotrophoblast defining maternal blood channels that drain the labyrinth. Yolk sac endoderm covers much of the fetal surface of the placenta. The subplacenta comprises cytotrophoblast and syncytiotrophoblast. There are dilated intercellular spaces between the cytotrophoblasts and lacunae lined by syncytiotrophoblast. In the junctional zone between subplacenta and decidua, there are nests of multinucleated giant cells with vacuolated cytoplasm. The entire placenta rests on a pedicle of maternal tissue. An inverted yolk sac placenta is also present. The presence of small vesicles and tubules in the apical membrane of the yolk sac endoderm and larger vesicles in the supranuclear region suggest that the yolk sac placenta participates in maternal-fetal transfer of protein.Conclusion: the paca placenta closely resembles that of other hystricomorph rodents. The lobulated structure allows for a larger exchange area and the development of precocial young.

Morfologia do figado da paca (Cuniculus Paca, Linnaeus 1766)

The elements related to the morphology of the liver of paca (Cuniculus paca), the second largest rodent of the Brazilian fauna, were observed; this species present zootechnical potential. Eight animals from the animals sector of Faculdade de Ciencias Agrarias e Veterinarias - Campus of Jaboticabal - UNESP, which is duly certified by IBAMA as an experimental breeding institute, were used. Through a dissection procedure, it was found that the liver of the paca is located in the cranial portion of the abdomen, immediately after the diaphragm, to which it is connected by the triangular, coronary, and falciform ligaments, having its bigger part located right to the medium plan. The liver of this rodent presents the following lobation: right lateral lobe, right medial lobe, quadrate lobe, left medial lobe, and left lateral lobe, besides the caudate lobe formed by the papillary process of caudate lobe and the caudate process of caudate lobe. Gallbladder is located between the quadrate and right medial lobes. Fragments of this organ were collected, fixed, and histologically prepared, being the samples analyzed through light microscopy. It was microscopically observed that intralobular connective tissue is scarce, basically it consists polyhedral hepatocytes organized into cords interposed between sinusoids and the portal triads are found in the lobe, consisting of the portal vein, hepatic artery, and biliary duct.