Anatomia microscópica e ultraestrutura do joelho da paca (Cuniculus paca Linnaeus, 1766) / Microscopic anatomy and ultrastructure of paca stifle (Cuniculus paca Linnaeus, 1766)

A paca (Cuniculus paca), um dos maiores roedores da fauna brasileira, possui características inerentes à sua espécie que podem contribuir como uma nova opção de animal experimental; assim, considerando-se que há crescente busca por modelos experimentais apropriados para ortopedia e pesquisas cirúrgicas, foram analisados e descritos em detalhes a anatomia microscópica e ultraestrutural do joelho desse roedor. Os ligamentos colaterais são constituídos por feixes de fibras colágenas arranjadas paralelamente e com trajeto ondulado. Os fibroblastos formavam fileiras paralelas às fibras colágenas; quanto aos ligamentos colaterais, estes apresentaram citoplasma imperceptível à avaliação por microscopia de luz, entretanto, em análise ultraestrutural verificou-se vários prolongamentos citoplasmáticos. Microscopicamente, as estruturas presentes no joelho da paca assemelham-se às dos animais domésticos, roedores e lagomorfos.(AU)

Paca (Cuniculus paca), one of the largest rodent of the Brazilian fauna, has characteristics inherent to the species that can contribute as a new experimental animal; so, considering that there is a growing search for experimental models suitable for orthopedic and surgical research, it was analyzed and described in detail the microscopic and ultrastructural anatomy of the stifle in this rodent. The collateral ligaments are composed of bundles of collagen fibers arranged in parallel and in wavy path. Fibroblasts formed parallel rows to the collagen fibers; concerning the collateral ligaments, they presented imperceptible cytoplasm at light microscopy, but at ultrastructure analysis they presented several cytoplasmic processes. At the microscopic level, the stifle of paca resembles the domestic animals, rodents and lagomorphs.(AU)

Immunohistochemical, lectin histochemical and ultrastructural studies of canine transmissible venereal tumor in Brazil / Estudos imuno-histoquímico, lectino-histoquímico e ultraestrutural do Tumor Venéreo Transmissível Canino no Brasil

Canine transmissible venereal tumor (CTVT) is a naturally occurring contagious round-cell neoplasia, with poorly understood origin and transmission. This study aims to further investigate the tumor nature through immunohistochemistry, lectin histochemistry and transmission electron microscopy (TEM) analysis, and to provide support for diagnostic and differential diagnoses of CTVT. Immunohistochemistry was performed in 10 genital and six exclusively extragenital tumors, which were previously diagnosed by citology and histopathology. CTVT samples were incubated with biotinylated antibodies to specific membrane and cytoplasmic antigens (anti-lysozyme, anti-macrophage, anti-vimentin, anti-CD18, monoclonal anti-CD117, monoclonal anti-CD3, polyclonal anti-CD117, polyclonal CD3 and anti-CD79a), followed by the avidin-biotin-peroxidase complex technique. The lectins Con A, DBA, SBA, PNA, UEA-1, WGA, sWGA, GSL, JSA, PSA, PHA-L, PHA-E and RCA were additionally tested in four genital CTVTs and TEM was performed in eight genital tumors. The anti-vimentin antibody revealed strong immunoreactivity to neoplastic cells in all the assessed samples (16/16). The polyclonal anti-CD3 antibodies showed moderate to strong immunoreactivity in fourteen (14/16) and the polyclonal anti-CD117 in fifteen cases (15/16). There was no immunoreactivity to anti-lysozyme, anti-macrophage, anti-CD18, monoclonal anti-CD117, monoclonal anti-CD3 and anti-CD79a antibodies. At lectin histochemistry, it was observed strong staining of tumor cells to Con-A, PHA-L and RCA. There was no histopathological and immunoreactivity differences between genital and extragenital CTVTs. These findings do not support the hypothesis of histiocytic origin of CTVT. In contrast, the lectin histochemical results were similar to cells from lymphoid/myeloid origin.(AU)

O Tumor Venéreo Transmissível Canino (CTVT) é uma neoplasia de células células redondas, contagiosa, com origem e transmissão ainda mal compreendidas. Com a finalidade de aprofundar a investigação sobre a natureza (origem) do TVTC, bem como fornecer subsídios para o estabelecimento do diagnóstico e diagnóstico diferencial, realizaram-se avaliações imuno-histoquímica, lectino-histoquímica e ultraestrutural de TVTC(s). A avaliação imuno-histoquímica foi feita em 10 TVTCs genitais e em 6 exclusivamente extragenitais previamente diagnosticados através de citologia e da histopatologia. Os TVTCs foram testados para reagentes específicos de antígenos de membrana e citoplasmáticos (anti-lisozima, anti-macrófago, anti-vimentina, anti-CD18, anti-CD3, anti-CD79, anti-CD117) com utilização da técnica complexo avidina-biotina-peroxidase. Adicionalmente, foram utilizadas as lectinas Con A, DBA, SBA, PNA, UEA-1, WGA, sWGA, GSL, SJA, PSA, PHA-L, PHA-E e RCA em quatro TVTCs genitais. Microscopia eletrônica foi realizada em oito TVTC genitais. Em 100% dos tumores testados (16/16) com anticorpo anti-vimentina (mono e policlonal) houve forte imuno-reatividade. Não houve reatividade para os anticorpos anti-lisozima, anti-macrófago, anti-CD18, anti-CD3, anti-CD79a e anti-CD117 quando empregamos anticorpos monoclonais, entretanto, com a utilização de anticorpos policlonais verificou-se marcação dos tumores com os anticorpos anti-CD3 e anti-CD117. Na avaliação lectino-histoquímica foi verificada forte marcação das células tumorais com Con-A, PHA-L e RCA. Não houve diferença histopatológica e de imuno-reatividade entre os TVTCs genitais e extragenitais. Estes achados não corroboram com a hipótese da origem histiocítica do CTVT (ausência de reatividade dos anticorpos anti-lisozima, anti-macrófago e anti-CD18), entretanto, os resultados da avaliação lectino-histoquímica foram em parte similares aos obtidos quando células de origem linfóide/mielóide (ConA, PHA-L e RCA) foram analisadas (Gimeno et al. 1995).(AU)

Aspectos morfológicos e ultraestruturais de células sanguíneas de Crotalus durissus terrificus / Morphological and ultrastructural aspects of Crotalus durissus terrificus blood cells

A avaliação hematológica, de importância comprovada como um meio auxiliar de diagnóstico ao clínico de pequenos animais domésticos, vem se tornando comum em animais selvagens não apenas para a clínica, mas para a avaliação do manejo e como estudo auxiliar para a fisiologia das várias espécies. Tendo em vista o aumento da demanda para a produção de várias drogas de importância farmacêutica, a criação de serpentes peçonhentas vem se tornando comum a ponto destes animais já serem reconhecidos como sendo de produção. O conhecimento do manejo e da clínica destes animais ainda é escasso e a mortalidade é elevada nos criatórios, tornando urgente a ampliação destes. Embora alguns estudos hematológicos já tenham sido realizados em cascavéis (Crotalus durissus) os dados analisados ainda são insipientes, notadamente em relação à caracterização das células do sangue e poucos estudos em microscopia eletrônica foram realizados em serpentes. Com o objetivo de caracterizar as células sanguíneas morfologicamente, sob microscopia óptica e ultraestrutural, foram coletadas amostras de sangue de 52 de indivíduos da subespécie Crotalus durissus terrificus para a realização de esfregaços sanguíneos e avaliação ultraestrutural. Concluiu-se que a coloração hematológica de Giemsa permite a avaliação morfológica e a diferenciação das células sanguíneas em serpentes assim como a visualização de hemoparasitos. A avaliação ultraestrutural permite evidenciar as organelas celulares e a diferenciação entre as células, inclusive entre os tipos leucocitários, porém ainda são necessários outros estudos para que seja elucidada a hipótese da existência dos eosinófilos na espécie estudada assim como é necessária melhor caracterização dos grânulos dos azurófilos para que se confirme uma possível diferença entre os monócitos típicos e os azurófilos.(AU)

Hematological evaluation, important for the diagnostic by the small domestic animal clinician, has become common in wildlife clinic, and for handling and study of the physiology of various species. Given the increased demand for drug production of pharmaceutical importance, the breeding of venomous snakes has become common and is already recognized as production. Knowledge of the management and clinics of snakes is still insufficient and their mortality is high. Although some hematological studies have already been conducted in the rattlesnake (Crotalus durissus), the analyzed data are still insufficient, especially with respect to the characterization of blood cells, and few electron microscopy studies have been performed on snakes. In order to characterize morphologically blood cells with light and ultrastructural microscopy, blood samples from 52 individuals of subspecies of Crotalus durissus terrificus were collected to perform blood smears and ultrastructural evaluation. It was concluded that hematologic Giemsa staining allows morphological evaluation and differentiation of the blood cells as well as of snake hemoparasites. The ultrastructural evaluation will highlight the cell organelles and differentiation between cells, including leukocyte types; although still further studies are needed to elucidate the hypothesis of eosinophils in the species studied as also is necessary a better characterization of azurophilic beads to confirm a possible difference between the typical monocyte and the azurophilic.(AU)

Development of the central nervous system in guinea pig (Cavia porcellus, Rodentia, Caviidae) / Desenvolvimento do sistema nervoso central em guinea pig (Cavia porcellus, Rodentia, Caviidae)

This study describes the development of the central nervous system in guinea pigs from 12th day post conception (dpc) until birth. Totally, 41 embryos and fetuses were analyzed macroscopically and by means of light and electron microscopy. The neural tube closure was observed at day 14 and the development of the spinal cord and differentiation of the primitive central nervous system vesicles was on 20th dpc. Histologically, undifferentiated brain tissue was observed as a mass of mesenchymal tissue between 18th and 20th dpc, and at 25th dpc the tissue within the medullary canal had higher density. On day 30 the brain tissue was differentiated on day 30 and the spinal cord filling throughout the spinal canal, period from which it was possible to observe cerebral and cerebellar stratums. At day 45 intumescences were visualized and cerebral hemispheres were divided, with a clear division between white and gray matter in brain and cerebellum. Median sulcus of the dorsal spinal cord and the cauda equina were only evident on day 50. There were no significant structural differences in fetuses of 50 and 60 dpc, and animals at term were all lissencephalic. In conclusion, morphological studies of the nervous system in guinea pig can provide important information for clinical studies in humans, due to its high degree of neurological maturity in relation to its short gestation period, what can provide a good tool for neurological studies.(AU)

Este estudo descreve o desenvolvimento do sistema nervoso central em guinea pig do 12º dia pós-concepção (dpc) até ao nascimento. No total, 41 embriões e fetos foram analisados macroscopicamente e por microscopia de luz e eletrônica. O fechamento do tubo neural foi observado no dia 14 e o desenvolvimento da medula espinhal e diferenciação das vesículas primitivas do sistema nervoso central foram observados no dia 20. Histologicamente, o tecido cerebral indiferenciado foi observado como uma massa de tecido mesenquimal entre os dias 18 e 20 e no 25º dia o tecido no interior do canal medular apresentou maior densidade. No dia 30 o tecido cerebral apresentou-se diferenciado, período no qual a medula espinhal preenchia todo o canal vertebral e foi possível observar os estratos cerebral e cerebelar. No dia 45 as intumescências cervical e lombar foram visualizadas e os hemisférios cerebrais estavam divididos, com uma clara distinção entre substância branca e cinzenta no cérebro e cerebelo. O sulco mediano dorsal da medula espinhal e a cauda equina foram evidentes apenas no dia 50. Não houve diferenças estruturais significativas em fetos de 50 e 60 dpc e animais a termo eram todos lisencefálicos. Estudos morfológicos do sistema nervoso em guinea pig podem fornecer informações importantes para estudos clínicos em seres humanos devido ao alto grau de maturidade neurológica em relação ao seu período de gestação curto, fato que servir como excelente ferramenta em estudos neurológicos.(AU)

Anatomical and histological characteristics of teeth in agouti (Dasyprocta prymnolopha Wagler, 1831) / Características anatômicas e histológicas dos dentes na cutia (Dasyprocta prymnolopha Wagler, 1831)

The agouti species Dasyprocta prymnolopha (D. prymnolopha) is a medium-sized rodent, diurnal, and characteristic of northeastern Brazil, south of the Amazon. Several studies have been made on these rodents. However, there is a lack of analysis of masticatory system, in particular morphology of the teeth. Thus, this research seeks to describe anatomical and histological aspects of the agouti teeth. For this purpose, we used adult agouti, in which measurements and descriptions of teeth and dental tissues were made. It was observed that the dental arch of D. prymnolopha comprises of twenty teeth, evenly distributed in the upper and lower arch, being inferior teeth larger than their corresponding higher. The incisors are larger, and between the posterior premolars and molars, there is a gradual increase in length in the anterior-posterior arch. In microscopic examination, a prismatic appearance was observed consisting of enamel prisms arranged in different directions, behind the enamel and dentin with standard tubular dentinal tubules with variable diameter and far between, also showing a sinuous path from the inner portion to the junction with more superficial enamel. Morphological analysis of dental tissues showed that an enamel with structural organization adapted to the act of chewing and high impact dentin compatible with standard tubular function resilience and mechanical damping of masticatory forces, as found in larger animals, confirming the understanding of eating habits that define much of its ecological functions within the ecosystem they inhabit.

A cutia espécie Dasyprocta prymnolopha (D. prymnolopha) é um roedor de tamanho médio, diurno e característico do Nordeste do Brasil, sul da Amazônia. Vários estudos têm sido feitos sobre estes roedores. No entanto, há uma carência de estudos do sistema estomatognático, em particular, a morfologia dos dentes. Assim, esta pesquisa procura descrever aspectos anatômicos e histológicos dos dentes cutia. Para isto, nós utilizamos cutias adultas, em que as mensurações e as descrições dos dentes e dos tecidos dentais foram feitas. Observou-se que a arcada dentária de D. prymnolopha é composta por vinte dentes, distribuídas uniformemente no arco superior e inferior, sendo os dentes inferiores, maiores do que os seus correspondentes superiores. Os incisivos são maiores, e entre os pré-molares e molares posteriores, existe um aumento gradual no comprimento do arco anterior-posterior. No exame microscópico, uma forma prismática foi observada o que consiste de prismas de esmalte dispostos em diferentes direções, atrás do esmalte e dentina com túbulos dentinários com padrão tubular de diâmetro variável e distantes entre si, mostrando também um caminho sinuoso a partir da parte interna da junção com o esmalte mais superficial. A análise morfológica dos tecidos dentários mostrou um esmalte com a organização estrutural adaptada para o ato de mastigar e dentina de alto impacto compatível com a função do padrão tubular de resiliência e amortecimento mecânico de forças mastigatórias, como encontrado em animais maiores, confirmando o entendimento de hábitos alimentares que definem muito das suas funções ecológicas dentro do ecossistema em que vivem.

The spleen of a specialy adapted mammal: the little hairy armadillo Chaetophractus vellerosus, (Xenarthra, dasypodidae): a light and electron microscopic study / El Bazo de un Mamífero con Adaptaciones Especiales: el "Peludo Chico" Chaetophractus vellerosus, (Xenarthra, Dasypodidae). Estudio con Microscopía de Luz y Electrónica

El bazo es un órgano multipotencial y en su microarquitectura se reflejan tanto la filogenia como la adaptación de cada grupo animal e inclusive de cada especie. Los armadillos son un clado antiguo y geográficamente aislado de mamíferos que muestra una mezcla de estructuras ancestrales y modernas. En este trabajo se estudian la microanatomía y citología del bazo del peludo chico Chaetophractus vellerosus. El material se fijó y procesó según las técnicas de rutina de microscopías óptica y electrónica. Los resultados muestran un órgano mediano, del tipo de acumulación, con la típica segregación de pulpas. La pulpa blanca está bien desarrollada pero menos organizada que en otros armadillos. Se observa la presencia de células morfológicamente similares a las foliculares dendríticas y a las interdigitantes, así como agrupamientos de células inmunocompetentes. Estas características apoyan la importancia del órgano en la función inmune. La pulpa roja es un entramado de espacios vasculares y células libres y fijas. Se reconocen, por primera vez en el Género, la presencia de sinusoides esplénicos. El tejido hemopoyético está presente pero menos desarrollado que en otros Euphractini. Se discute la organización y el tamaño del bazo en contextos filogenético y adaptativo.

The spleen is a multifunctional organ. Its microarchitecture reflects so well the phylogeny as the adaptation to niche in each animal group and inclusive in each species. Armadillos, as ancient and isolated mammals, show a mixture of ancestral and modern structures. In this work the microanatomy and cytology of the spleen of the little hairy armadillo Chaetophractus vellerosus was studied. The material was fixed and processed according to the typical methods for light and electron microscopy. Results show a cumulative medium sized spleen with the typical pulps. The white pulp is well developed but less defined than in other armadillos. The presence of follicular-dendritic-like cells and interdigitant dendritic-like cells, as well as clusters of immunocompetent cells agrees with an active immunological activity. The red pulp is a meshwork of circulatory spaces and cells. The presence of splenic sinusoids is recognized for the first time in the genus. Hemopoietic tissue is less developed than in other Euphractini. The microarchitecture and size of the spleen of C. vellerosus is discussed in a phylogenetic and adaptive context.

Transmission Electron Microscopy Study of the Neonatal Rat Tongue Mucosa Treated with Special Attention to the Bacteriae on the Epithelial Cell Membrane

RESUMEN: A través de miscroscopía electrónica de transmisión se examinaron las células del epitelio de la mucosa lingual de ratas Wistar recién nacidas. Los tejidos fueron fijados en solución de Karnovksy modificada e incluidos en resina Spurr. Se obtuvieron delgados cortes de 90 nm y se observaron al microscopio electrónico de transmisión Jeol 1010. Se encontró que las células epiteliales queratinizadas escamosas de la mucosa lingual expuestas al cadmio, presentaron grupos de numerosas bacterias las cuales estaban fijadas a las superficies de las membranas celulares. Los cocos y bacilos estaban fijados a las membranas celulares organizadas en pilas o columnas o al azar, como se aprecia claramente en las imágenes obtenidas a través de la microscopía electrónica de transmisión. Las imágenes mostraron que las bacterias estaban fijadas por estructuras fibrilares desde una a otra y desde las memebranas de las células epiteliales a las bacterias. El grupo control demostró que en las membranas celulares no era evidente la presencia de cadmio.

Structural and ultrastructural characterization of zebu (Bos indicus)spermatozoa

The ultrastructure of normal, ejaculated spermatozoa of Bos indicus was studied by means of electron microscopy, being evaluated in two principal parts, the head and the tail. The head is flat, oval or paddle-shaped with a square base, which provides a concave recess for the insertion of the tail. The acrosome tightly covers the anterior two thirds of the nucleus. A distinct unilateral acrosomal bulge was observed along the apical edge of the head. The equatorial region demarcates the acrosome from the post-equatorial region that covers the caudal one third of the nucleus. The classical 9+9+2 fiber pattern which composes the axoneme was observed along three segments of the tail, namely middle, principal and terminal pieces. The axoneme is anteriorly bound by the mitochondrial helix (middle piece) and posteriorly by the fibrous helix (principal piece), except at the terminal piece. The border between the middle piece and principal piece was well defined due to the termination of the thick mitochondrial helix and the presence of the annulus. Some of the spermatozoa presented cytoplasmatic droplets, which appeared as stalk-like appendages.

Biophysical characterization of Japanese encephalitis virus (KV1899) isolated from pigs in Korea

A virus strain, showing cytopathic effect in Vero cell, was isolated from plasma of a fattening pig in Gyeonggi province, Korea in October 1999. The evaluation of physicochemical/biological properties of the isolate showed that the virus, KV1899, inoculated suckling mouse showed paralysis and died within 7 days post-inoculation, the mouse brain suspension had hemagglutinating activity with goose RBC. Pathogenicity of isolate was carried out by intracranial and intraperitoneal inoculation of 3-4 weeks mice. The mice inoculated with isolate showed 10 4.5 LD50/ 0.03 ml and 10 3.0 LD50/0.5 ml according to the inoculation route. The isolate was identified as RNA and enveloped virus using IUDR and chloroform sensitivity test. The virus particles within the infected Vero cell were measured to be 40-50 nm in size by electron microscopy. The isolate was further characterized by immuno-fluorescence assay using Japanese encephalitis virus (JEV) specific monoclonal antibodies. Reverse transcription polymerase chain reaction (RT-PCR) revealed the presence of JE specific conserved sequences in this isolate. The artificially inoculated pigs had HI titer of 320 to 2,560 against JEV at 14 to 42 days post inoculation. We confirmed this isolate as Japanese encephalitis virus. It was the second isolation of JEV in pigs in Korea.

Inherited canine copper toxicosis in Australian Bedlington Terriers

Inherited copper toxicosis in Bedlington Terriers (CTBT) is a copper associated hepatopathy caused by an autosomal recessive genetic defect of gene involving copper metabolism. To compare clinical and histopathological findings with previous reports and to expand our knowledge for future genetic studies, 18 terriers were clinically and histopathologically examined in this study. Pedigree information and dietary history were obtained from the owners before a thorough clinical examination was undertaken. Following the examination, a blood sample was collected for haematology, biochemistry and genetic analysis and a urine sample for urinalysis. Seven dogs were also liver biopsied for histopathology, histochemistry and electron microscopy. In this study, plasma alanine transaminase (ALT) activity was highly concordant with DNA marker test results and was the most reliable and sensitive biochemical test measured. Also clinical and biochemical copper toxicosisaffected states were noticed in a genotyped carrier dog. Histopathological and electron microscopy findings showed that the severity of the lesion was more closely correlated to the presence of clinical signs than to hepatic copper concentration. In addition, the involvement of apoptosis and p53 gene was observed in electron microscopy. The general findings related to CT-BT in this study was similar to those previously reported except few differences in histopathology and electron microscopy.