Sincronização do estro em pacas (Cuniculus paca L.): possíveis impactos sobre parâmetros reprodutivos e produtivos

Estrus synchronization is a reproductive biotechnology used to improve artificial insemination or pairing through the manipulation of the estrous cycle at a desirable time. Employing this technique in captive pacas (Cuniculus paca L.) is important because it creates expectation of meeting the demand for paca meat and, consequently, reduces poaching. Thus, this research aims to verify the effect of a progestogen implant associated with two doses of eCG on the synchronization and induction of fertile estrus. Twenty-seven adult pacas were used, 18 non-pregnant females and nine males, divided into three groups. G1 and G2 females groups (treatments) received 1.5 mg Norgestomet and were injected intramuscularly, seven days later, with 0.13 mg of prostaglandin. After 24 hours the implants were removed and the animals immediately received 25 IU and 50 IU of ECG intramuscularly, respectively. The mating of the three groups took place on the same days. G3 females’ group (control) showed estrus on different days after D0. Females under treatment displayed estrus only after removing the implant (D8). G1, G2, and G3 pregnancy rates were 100%, 66%, and 50%, respectively. Regarding births per parturition, 100% of G1 and G3 produced one offspring, while 50% of G2 produced two. Progestogen in the form of subcutaneous implants was effective in mimicking the luteal phase of the estrous cycle. After removal, implants favored the occurrence of a fertile estrus. As a conclusion, further studies must be conducted in order to establish in-depth possible association between 50 IU of eCG, and the occurrence of twin pregnancies.A sincronização é uma biotécnica reprodutiva que melhora a porcentagem de cobertura por meio da manipulação do ciclo estral. Empregar esta biotécnica em pacas de cativeiro (Cuniculus paca L.) é importante, pois cria-se a expectativa de que a demanda pela carne seja atendida e a caça ilegal diminua. O objetivo da pesquisa foi verificar o efeito de implantes de progestágenos associados a duas doses de gonadotrofina coriônica equina (eCG) na sincronização e indução de cios férteis de pacas. Foram utilizadas 18 fêmeas não prenhas e nove machos, divididos em três grupos. Fêmeas do G1 e G2 receberam implantes com 1,5mg de Norgestomet e, sete dias depois, 0,13mg de prostaglandina via intramuscular (IM). No dia 8 (D8), foram retirados os implantes e G1 e G2 receberam 25 UI e 50 UI de eCG, IM, respectivamente; G3 foi o controle. O pareamento nos três grupos aconteceu nos mesmos dias. As fêmeas do G3 apresentaram cio alguns dias após o dia zero (D0). Fêmeas que receberam tratamento apresentaram cio só após a retirada do implante no dia 8 (D8). As taxas de prenhez de G1, G2 e G3 atingiram 100%, 66% e 50%, respectivamente. Em relação a filhotes por parto, 100% do G1 e G3 produziram uma cria, enquanto 50% do G2 produziram duas crias. O progestágeno do implante foi eficaz em mimetizar a fase lútea do ciclo estral. Após a remoção, o tratamento hormonal favoreceu a ocorrência de cio fértil. Outros estudos devem ser realizados a fim de estabelecer uma possível associação entre 50 UI de eCG e a ocorrência de gestações gemelares

Morphological and biochemical aspects of the calcaneal and the superficial digital flexor tendons of chickens during aging

Orientador: Laurecir GomesDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: O tendão calcanear e o tendão flexor digital superficial de frangos são estruturas adaptadas para resistir às forças de tensão geradas pelos músculos e transmitidas para os ossos. Em algumas regiões, estes tendões também suportam forças de compressão adicionais às de tensão. Durante o envelhecimento os tendões apresentam modificações nas regiões sujeitas à compressão e a tensão, com variações na composição da matriz extracelular, disposição de fibras de colágeno e celularidade, assim como em suas interações com outros componentes da matriz. O objetivo desse trabalho foi analisar a organização estrutural e a composição da matriz extracelular das regiões submetidas à tensão e a tensão-compressão em diferentes idades (1 mês, 5 meses e 8 meses). O tendão calcanear e o tendão flexor digital superficial foram divididos em região proximal (tensão-compressão) e distal (tensão). Os resultados morfológicos, em ambos os tendões, mostraram presença de uma estrutura fibrocartilaginosa na região sujeita as forças de tensão-compressão. No tendão calcanear foi possível observar ainda, presença de um coxim gorduroso, que se acentuou com o passar da idade. Esse coxim funciona como um amortecedor, uma vez que essa região é muito requisitada durante a locomoção do animal. Já a região que recebe apenas forças de tensão apresentou alterações marcantes nos diferentes tendões em relação aos animais mais jovens. No tendão calcanear dos animais mais velhos, as fibras de colágeno estão mais compactadas exibindo poucas ondulações e células com núcleos alongados, enquanto que no tendão flexor digital superficial essa região apresentou-se com pontos de calcificação, de forma que essa morfologia pode indicar o início do estabelecimento de uma matriz óssea. Análises bioquímicas apresentaram, tanto no tendão calcanear como no tendão flexor digital superficial, aumento da atividade da MMP-2 e MMP-9 comparados aos animais mais jovens, em ambas as regiões, indicando um processo de remodelamento no tecido. No SDS-PAGE do tendão calcanear, componentes com migração eletroforética semelhante ao decorim e fibromodulim aumentaram com o avanço da idade, principalmente na região sujeita às forças de tensão, enquanto que no SDFT o decorim aparentemente diminuiu com o envelhecimentoAbstract: The calcaneal and the superficial digital flexor tendons of chickens are structures adapted to resist to tensile forces generated by the muscles and transmitted to the bones. In some regions, these tendons also support compressive forces additional to the tension forces. During aging tendons exhibit modifications in regions subjected to compression and tension forces, with variations in the composition of the extracellular matrix, arrangement of collagen fibers and cellularity, as well as in its interactions with other matrix components. The aim of this study was to analyze the structural organization and composition of the extracellular matrix regions subjected to tension and tension-compression forces at different ages (1 month, 5 months, 8 months old). The calcaneal and the superficial digital flexor tendons were divided into proximal (tension-compression) and distal (tension) regions. The morphological results, in both tendons, showed presence of a fibrocartilage structure in the region subject to the compression-tension forces. In the calcaneal tendon was also observed the presence of a fat pad, that increased with age. This structure act absorbing the mechanical impacts, once this region is required during the locomotion of the animal. The region that receives only tension forces had marked alterations in different tendons compared to younger animals. In the calcaneal tendon of older animals, the collagen fibers are more compact exhibiting few ondulations and cells with elongated nuclei, whereas in the superficial digital flexor tendon this region exhibit calcification points. This morphology may indicate the beginning of the establishment of a bone matrix. Biochemical analyzes showed in both tendons, increased activity of MMP-2 and MMP-9 compared to younger animals, in both regions, indicating a remodeling process in the tissue. In SDS-PAGE of the calcaneal tendon, components with electrophoretic migration similar to decorin and fibromodulin increased with advanced age, especially in the area subject to tensile forces, whereas in the SDFT decorin apparently decreased with agingMestradoBiologia TecidualMestra em Biologia Celular e Estrutura

Canine transmissible venereal tumor: expression of MDR-1, and TP53 and BCL-2 family genes and its implications in biological and therapeutic behavior

Transmissible venereal tumor (TVT) is a neoplasm of round cells with plasmocytoid or lymphocytoid appearance. The tumor presents several particularities, which have been the subject of numerous studies; however there still have investigations that need to be done. For example, a progressive increase of highly aggressive tumors with varying response to chemotherapy -including resistance- has been evidenced in recent years. There is scientific interest to understand these differences, allowing predicting possible clinical outcomes in affected dogs and increasingly searching adequate and individualized therapy. This review focuses on presenting possible implications of the expression of MDR-1 (P-glycoprotein), TP53, BCL-2, and BAX genes, regarding resistance to chemotherapy and/or the biologic behavior of TVTO tumor venéreo transmissível (TVT) é uma neoplasia de células redondas de aspecto plasmocitóide ou linfocitóide. O tumor apresenta várias particularidades que tem sido objeto de numerosas investigações e apesar disso, ainda existem lacunas que necessitam de maiores estudos. Por exemplo, nos últimos anos, tem-se evidenciado um aumento progressivo de tumores que apresentam elevados porcentuais de agressividade e variável resposta à quimioterapia, inclusive resistência. Desta forma, atualmente há interesses científicos com relação a compreender melhor estas diferenças, permitindo predizer uma possível evolução clínica entre cães acometidos pelo tumor e buscando cada vez mais uma conduta terapêutica adequada e individualizada. Assim, a revisão de literatura, centra-se em apresentar possíveis implicações da expressão dos genes MDR-1 (glicoproteína-p), TP53, BCL-2, BAX, quanto à resistência à quimioterapia, e/ou comportamento biológico do TVT.El tumor venéreo transmisible (TVT) es una neoplasia de células redondas de aspecto plasmocitoide o linfocitoide. El tumor presenta varias particularidades que han sido objeto de numerosas investigaciones y a pesar de eso, aún existen algunos vacíos en su conocimiento que requieren mayores estudios. Por ejemplo, en los últimos años, se ha evidenciado un aumento progresivo de tumores que presentan elevados porcentajes de agresividad y una respuesta variable a la quimioterapia, inclusive alguna resistencia. En este sentido, actualmente hay intereses científicos con relación a comprender mejor estas diferencias, permitiendo predecir una posible evolución clínica entre perros afectados por el tumor y buscando cada vez más una conducta terapéutica adecuada e individualizada. Así, la revisión de literatura, se centra en presentar posibles implicaciones de la expresión de los genes MDR-1 (glicoproteína-p), TP53, BCL-2, BAX, en cuanto a la resistencia a la quimioterapia, y/o el comportamiento biológico del TV

Changes In The Connective Tissue Sheath Of Wistar Rat Nerve With Aging.

The alterations due to aging in the peripheral nerves can affect the physiology of these structures. Thus, the purpose of the present study was to describe the activity of the MMP-2 and MMP-9, as well as the structure and composition of the extracellular matrix of the rat sciatic nerve during maturation and aging. Our results have shown that the extracellular matrix of the sciatic nerve of 30-, 180- and 730-day-old Wistar rats present ultrastructural, morphometrical and biochemical changes during aging. The perineurium was the structure most affected by age, as evidenced by a decrease in thickness and in collagen fibril content. Cytochemical analysis detected proteoglycans in the basal membrane of Schwann cells and around perineural cells, as well as on the collagen fibrils of the perineurium and endoneurium at all ages. Biochemical analyses showed that the quantity of non-collagenous proteins was higher in 730-day-old animals compared to other ages, while the uronic acid content was higher in 30-day-old animals. Morphometrical analysis detected greater numbers of myelinated fibers and increased myelin thickness in 180-day-old animals. Zymography analysis detected greater amounts and activity of MMP-2 and MMP-9 in 180- and 730-day-old animals compared to younger rats. In conclusion, our results showed changes in the structural organization and composition of extracellular matrix of the sciatic nerve during aging, such as increase in the non-collagenous protein content and higher MMP-2 and MMP-9 activity, decrease in uronic acid concentration and in collagen fibril content in the perineurium, as well as degeneration of nerve fibers.196441-

Biochemical And Morphological Alterations Of The Extracellular Matrix Of Chicken Calcaneal Tendon During Maturation.

The region in tendons that surrounds bone extremities adapts to compression forces, developing a fibrocartilaginous structure. During maturation, changes occur in the amount and organization of macromolecules of the extracellular matrix of tendons, changing the tissue morphology. To study the effect of maturation on tendons, Pedrês chickens were sacrificed at 1, 5, and 8 months old and had the calcaneal tendon (CT) divided into proximal region, submitted to tension/compression forces (p), and distal region submitted to tension force (d). Morphological analysis of the p region showed the presence of fibrocartilage in all ages. In the central part of the fibrocartilage, near a diminishment of the metachromasy, there was also a development of a probable fat pad that increased with the maturation. The activity of MMP-2 and MMP-9 was higher at 5 and 8 months old, in both regions, compared with 1-month-old animals. In SDS-PAGE analysis, components with electrophoretic migration similar to decorin and fibromodulin increased with maturation, particularly in the d region. The Western blotting confirmed the increased amount of fibromodulin with maturation. In conclusion, our results show that process of maturation leads to the appearance of a probable fat pad in the center of the fibrocartilage of CT, with a reduced amount of glycosaminoglycans and an increased activity of MMPs.78949-95

Cell cycle kinetics, apoptosis rates and gene expressions of MDR - 1, TP53, BCL - 2 and BAX in transmissible venereal tumour cells and their association with therapy response.

Transmissible venereal tumour (TVT) generally presents different degrees of aggressiveness, which makes them unresponsive to conventional treatment protocols. This implies a progressive alteration of their biological profile. This study aimed to evaluate the cytotoxicity, cell survival, apoptosis and cell cycle alterations in TVT cell cultures subjected to treatment with vincristine. Similarly, it assessed possible implications of MDR-1, TP53, BCL-2, and BAX gene expressions in eight TVT primary cultures for both resistance to chemotherapy and biological behaviour.When comparing TVT cells receiving vincristine to those untreated, a statistical difference related to increased cytotoxicity and decreased survival rates, and alterations in G1 and S cell cycle phases were found but without detectable differences in apoptosis. Increased MDR-1 gene expression was observed after treatment. The groups did not differ statistically in relation to the TP53, BAX and BCL-2 genes. Although preliminary, the findings suggest that such augmented expression is related to tumour malignancy and chemotherapy resistance