Vanessa Cristina Oliveira

Marsupial morphology of reproduction: South America opossum male model

This study aims to describe the morphology of Didelphis sp. male genital organs (penis, testes, epididymis, ductus deferens, prostate, and bulbourethral gland). Ten male animals were used, eight for macroscopic and light microscopy analysis, and two for scanning electron microscopy. The testes and epididymis showed similarity to other eutherian mammals. The bifid penis showed the urethra ending in the medial region where the bifurcation begins, occurring in each segment extension of the urethral groove until the beginning of the glans. Histologically, the penis consists of a cavernous and spongy body, covered by stratified squamous epithelium with loose connective tissue. The urethra was lined by transitional stratified epithelium. In the prostate, prostatic segments were found consisting of tubular glands in a radial arrangement around the urethra, coated externally by a dense connective tissue associated with a relatively thick layer of smooth muscle arranged in two layers that surround the glandular tissue. The animals had three pairs of bulbourethral glands placed at the membranous and cavernous urethra junction with descending and parallel excretory ducts ending caudally in the urethral lumen. Microsc. Res. Tech. 76:388–397, 2013.

A morphological analysis of the transition between the embryonic primitive intestine and yolk sac in bovine embryos and fetuses

The yolk sac (YS) is the main source of embryonic nutrition during the period when the placenta has not yet formed. It is also responsible for hematopoiesis because the blood cells develop from it as part of the primitive embryonic circulation. The objective of this study was to characterize the transitional area between the YS and primitive gut using the techniques of light microscopy, transmission electron microscopy, and immunohistochemistry to detect populations of pluripotent cells by labeling with Oct4 antibody. In all investigated embryos, serial sections were made to permit the identification of this small, restricted area. We identified the YS connection with the primitive intestine and found that it is composed of many blood islands, which correspond to the vessels covered by vitelline and mesenchymal cells. We identified large numbers of hemangioblasts inside the vessels. The mesenchymal layer was thin and composed of elongated cells, and the vitelline endodermal membrane was composed of large, mono‐ or binucleated cells. The epithelium of the primitive intestine comprised stratified columnar cells and undifferentiated mesenchymal cells. The transitional area between the YS and the primitive intestine was very thin and composed of cells with irregular shapes, which formed a delicate lumen containing hemangioblasts. In the mesenchyme of the transitional area, there were a considerable number of small vessels containing hemangioblasts. Using Oct4 as a primary antibody, we identified positive cells in the metanephros, primordial gonad, and hepatic parenchyma as well as in YS cells, suggesting that these regions contain populations of pluripotent cells. Microsc. Res. Tech. 76:756–766, 2013.

Characterization of putative haematopoietic cells from bovine yolk sac

The yolk sac is an extra‐embryonic membrane that plays an important role in early embryonic survival. It is the production site for blood cells during embryonic mammalian development and is a likely source of stem cells. The aim of this study was to identify and characterize the putative haematopoietic cells from the yolk sac of bovine embryos at different stages of gestation. The yolk sac regresses according to gestational age and embryos are characterized into groups (I–V) according to the crown–rump measurement. Groups I–III survived in culture longer and exhibited the formation of cell clusters, whereas groups IV and V could not be maintained in culture for an extended period of time. Flow‐cytometry analysis revealed that groups I–III had similar characteristics, including high expression levels of the haematopoietic markers CD34, CD90 and CD117. In groups IV and V, decreases were observed in the expression levels of CD117 and CD34. Cells were found to be capable of survival post‐cryopreservation and exhibited varying abilities to form colonies in a methylcellulose matrix, depending on gestational age. Cytological analysis revealed the presence of blood cells (lymphocytes and monocytes). Quantitative PCR analysis demonstrated the presence of the haematopoietic progenitor genes GATA3 and LMO2, but not RUNX1. Thus, we have successfully isolated and characterized haematopoietic cells from the bovine embryo yolk sac at varying gestational ages. This study is crucial for the understanding of the development of the haematopoietic system and the embryonic function of this organ. Copyright

Controversial results of therapy with mesenchymal stem cells in the acute phase of canine distemper disease.

Distemper disease is an infectious disease reported in several species of domestic and wild carnivores. The high mortality rate of animals infected with canine distemper virus (CDV) treated with currently available therapies has driven the study of new efficacious treatments. Mesenchymal stem cell (MSC)-based therapy is a promising therapeutic option for many degenerative, hereditary, and inflammatory diseases. Therefore, the aim of this study was to characterize stem cells derived from the canine fetal olfactory epithelium and to assess the systemic response of animals infected with CDV to symptomatic therapy and treatment with MSCs. Eight domestic mongrel dogs (N = 8) were divided into two groups: support group (SG) (N = 5) and support group + cell therapy (SGCT) (N = 3), which were monitored over 15 days. Blood samples were collected on days 0, 6, 9, 12, and 15 to assess blood count and serum biochemistry (urea, creatinine, alanine transferase, alkaline phosphatase, gamma-glutamyl transferase, total protein, albumin, and globulin), and urine samples were obtained on days 0 and 15 for urinary evaluation (urine I). The results showed a high mortality rate (SG = 4 and SGCT = 2), providing inadequate data on the clinical course of CDV infection. MSC therapy resulted in no significant improvement when administered during the acute phase of canine distemper disease, and a prevalence of animals with high mortality rate was found in both groups due to the severity of symptoms.

Análise microscópica e ultraestrutural das glândulas salivares mandibulares de Procyon cancrivorus

Due to the ecological importance of Procyon cancrivorus, the aim of this study was to characterize morphologically and ultrastructurally the mandibular salivary gland of this specie. We used 10 pairs (right and left) of mandibular salivary glands from five adult animals. The mandibular salivary glands were dissected and measured by precision calipers and later processed by histological routine technique, stained by HE (hematoxylin and eosin) and Picrossirius. Fragments of the glands were processed for analysis by scanning electron microscopy (SEM). The mandibular salivary gland, right and left from P. cancrivorus presents lobulated and oval-shape, and it was positioned between the fossa atlantis and basihyoideum ossis of skull. Microscopically, these glands are lined by a capsule formed by dense irregular connective tissue, which enters into the gland by septa, dividing it into lobules. Into the septa of connective tissue were present blood vessels and nerves, and interlobular excretory ducts. Inside the lobes of the mandibular salivary glands, striatum and intermediate-type ducts are found, and the predominance of mucous acini was observed. The results indicate that the mandibular salivary glands of Procyon cancrivorus, follows the structural pattern described in other mammalian species. However the types of acini may vary among species, and thus further histochemical and cell biology studies are required in order to uncover the significance of this variation for the specie here studied, according with their feeding habit.

Characterization of yolk sac proteins of Bos indicus cattle embryos

The yolk sac is an embryonic membrane that is essential for the embryos initial survival in many mammals. It also plays an important role in the production of proteins necessary for development. We studied proteins of the yolk sac in bovine embryos at up to 40 days of gestation. We examined the yolk sac of 17 bovine embryos at different gestational periods, measuring α-fetoprotein, α-1-antitrypsin, and transferrin. This experiment was carried out by Western blot technique, associated with electrophoresis on a 6% sodium dodecyl sulfate polyacrylamide gel. Mouse monoclonal antibody anti-human-α-fetoprotein, mouse antibody anti-human-transferrin and rabbit polyclonal anti-human-α-1-antitrypsin were used as primary antibodies, and conjugated peroxidase as a secondary antibody. We detected the three proteins in some of the yolk sac samples; however, the bands in some specimens (samples) were weak, maybe a result of poor antigen-antibody reaction, since the antibodies used in this study were not specific to bovine proteins. The fact that weak bands appeared might be due to a weak cross-reaction.

Maintenance of Brazilian Biodiversity by germplasm bank

Currently the importance of using alternative strategies for biodiversity conservation is emphasized and since the establishment of germplasm bank is an alternative to the conservation of endangered species. This is a technique of great importance for the maintenance of Brazilian fauna. Since the early70sthere was a growing concern about the need to preserve essential genetic resources for food and agriculture, mainly for conservation of genetic material from farm animals. Thus was created the Brasilia Zoo, in July 2010, the first Germplasm Bank of Wild Animals in Latin America, as an alternative strategy for the conservation of threatened or endangered species, using both gametes and somatic cells and stem cells. Then we argue to create new banks or research networks among different regions with aimed to tissue preservation.

Morfologia macro e microscópica das papilas linguais do quati (Nasua nasua)

The coati (Nasua nasua) is an animal that belongs to the Procyonidae family. For this study we used three orthotanasized animals of both sexes, obtained from the Scientific Center for Wild Animal Breeding, University Center Octavio Bastos Educational Foundation (Cecrimpas, Unifeob), authorized by IBAMA (Proc.02027.003731/04-76). For microscopic analysis, tongues were processed routinely through electron microscopy scanning and inclusion in Paraplast; for light microscopy, the fragments were cut by microtome with an average thickness of 5mm and stained with H&E and Picrosirius counterstained with hematoxylin. The macroscopic and microscopic results show that the tongue of coati has filiform, fungiform, vallate and conical papillae distributed in the rostralis, medialis and caudalis regions. Histologically, the tongue is lined by a keratinized stratified squamous epithelium with spinous, granulous and keratin basal layer, with striated longitudinal and transverse skeletal muscles fibers, and several glands. We can conclude that coati´s tongue has macroscopic and microscopic features similar to the ones of Canidae, with differences in the number of vallate papillae and degree of keratinization.

Análise cinemática da marcha de cães Golden Retriever saudáveis

Kinematic analysis relates to the relative movement between rigid bodies and finds application in gait analysis and other body movements, interpretation of their data when there is change, determines the choice of treatment to be instituted. The objective of this study was to standardize the march of Dog Golden Retriever Healthy to assist in the diagnosis and treatment of musculoskeletal disorders. We used a kinematic analysis system to analyse the gait of seven dogs Golden Retriever, female, aged between 2 and 4 years, weighing 21.5 to 28 kg, clinically normal. Flexion and extension were described for shoulder, elbow, carpal, hip, femorotibialis and tarsal joints. The gait was characterized lateral and had accepted hypothesis of normality for all variables, except for the stance of hip and elbow, considering a confidence level of 95%, significance level α = 0.05. Variations have been attributed to displacement of the stripes during movement and the duplicated number of reviews. The kinematic analysis proved to be a consistent method of evaluation of the movement during canine gait and the data can be used in the diagnosis and evaluation of canine gait in comparison to other studies and treatment of dogs with musculoskeletal disorders.

Classificação Morfológica da Glândula Prepucial do Nasua nasua (Quati).

A proposta desta pesquisa e descrever a glândula prepucial do Nasua nasua. Utilizaram-se oito quatis provenientes do Criatόrio Cientifico Cecrimpas (Unifeob); as glândulas prepuciais foram analisadas, dissecadas e descritas macro e microscopicamente, visando estabelecer sua classificacao morfofuncional para, assim, poder compara-las com as de outras especies ja descritas na literatura. Amostras de tecido glandular foram coletadas, coradas (Hematoxilina e Eosina, Azul Toluidina, e Picrosirius) e analisadas atraves da microscopia de luz. Todos os resultados foram compilados e fotodocumentados. Na especie citada, essa glândula tem como principal funcao a demarcacao territorial e esta situada na porcao prepucial do mesmo modo que nos javalis. Em outros animais, como primatas, cervideos e roedores, essas glândulas demarcatόrias estao localizadas em diferentes regioes anatomicas, como entre os olhos, no metatarso, nas areas perianais e esternais. Em nosso resultado das medidas biometricas, obtivemos como media 3,8 ± 1,41cm de largura, 3,15 ± 0,93cm de altura e 10,26 ± 1,89cm de circunferencia, e essa glândula foi histologicamente classificada como do tipo tubuloalveolar, com secrecao holόcrina.