Conditioned medium: a new alternative for cryopreservation of equine umbilical cord mesenchymal stem cells.

Cryopreservation is a feasible alternative to maintaining several cell lines, particularly for immediate therapeutic use, transportation of samples, and implementation of new in vitro studies. This work parts from the hypothesis that the medium of cryopreservation composed by 90% of conditioned medium (CM) supports cryopreservation of equine umbilical cord intervascular matrix mesenchymal stem cells (UCIM-MSCs), allowing the maintenance of the biological properties for the establishment of cell banks intended for therapeutic use and in vitro studies. Thus, we evaluated the viability, apoptosis/necrosis rates, immunophenotypic profile (IP), chromosomal stability, clonicity, and differentiation potential of UCIM-MSCs cryopreserved with four different mediums (with FBS: M1, M3, M4 and without FBS: M2). After 3 months of cryopreservation, samples were thawed and analyzed. The potential of differentiation in the mesodermal lineages, clonicity, and the chromosomal stability were maintained after cryopreservation of UCIM-MSCs with medium containing FBS. Changes (P < 0.05) at IP for some markers were observed at cells cryopreserved with medium M1-M3. Only the UCIM-MSCs cryopreserved with the CM (M4) had similar viability post-thaw (P = 0.23) when compared with fresh cells. We proved the hypothesis that the medium of cryopreservation containing CM supports the cryopreservation of UCIM-MSCs, at the experimental conditions, being the medium that better maintains the biological characteristics observed at fresh cells. Thus, future studies of UCIM-MSCs secretome should be conducted to better understand the beneficial and protective effects of the CM during the freezing process.

Cytogenetic and molecular characterization of Speothos venaticus specimens / Caracterização citogenética e molecular de exemplares de Speothos venaticus

The bush dog (Speothos venaticus) is a South American canid, included in the IBAMA (Brazilian Institute of Environment and Renewable Natural Resources) official list of animals threatened with extinction, in the vulnerable category. As a preservation and conservation strategy, specimens kept in captivity by Brazilian Institutions are monitored by a management plan. In order to characterize and analyze the genetic variability of bush dog specimens, a cytogenetic analysis was carried out, and microsatellite data were also obtained through the use of 15 primers, originally developed for the domestic dog (Canis familiaris). All tested primers showed transferability and amplified fragment sizes similar to those described for the canine genome. From the total number of primers, eight were tested, and presented two polymorphic regions. Regarding cytogenetic analysis, one of the animals had chromosomal mosaicism, disqualifying it as a reproducer to form stocks. Thus, we concluded that the genetic evaluation of wild animals kept in captivity provides data that can help with the practice of exchange between different institutions, avoiding problems in the reproductive capacity of the breeding stock.

O cachorro-vinagre (Speothos venaticus) é um canídeo sul americano que está na lista oficial do Ibama de animais ameaçados de extinção, na categoria vulnerável. Como estratégia de preservação e conservação, os espécimes mantidos em cativeiro por instituições brasileiras são acompanhados por um plano de manejo. Visando a caracterização genética e posterior análise de variabilidade genética de exemplares de cachorro-vinagre, foi feita a análise citogenética e testou-se a transferabilidade de 15 primers de regiões microssatélites desenvolvidos para o cachorro doméstico (Canis familiaris) para esta espécie de canídeo. Todos os primers testados mostraram transferabilidade, com fragmentos amplificados de tamanhos semelhantes aos descritos para o genoma canino. Do total de primers, oito foram testados em 25 animais cativos e, dentre estes, duas regiões apresentaram polimórficas. Em relação à análise citogenética, um dos animais analisados apresentou mosaicismo cromossômico, desqualificando-o para utilização como reprodutor na formação de plantéis. Os demais exemplares apresentaram padrão cariotípico esperado para a espécie. Desta forma, concluiu-se que a avaliação genética de animais silvestres criados em cativeiro fornece dados que podem auxiliar com a prática de intercâmbio entre animais de diferentes instituições, evitando o comprometimento na capacidade reprodutiva do plantel.

The karyotype of Cabassous unicinctus (Dasypodidae, Xenarthra)

Abstract ­ Armadillos was belonged to the Xenarthra Order, Dasypodidae family. This family has been comprising the largest number of genera and species among the Xenarthrans; eight (8) and 21, respectively. Two adult males of the species Cabassous unicinctus were analyzed in this study. Lymphocyte cultures from whole blood were used and the cells were then submitted to conventional staining by C- and Ag-NOR banding. Data regarding the number of chromosomes showed discrepancies among the species described in the literature. The 46 chromosomes observed were distributed in six large metacentric pairs, five medium submetacentric pairs, five medium and small metacentric pairs and six acrocentric pairs. The Y chromosome was classified such as the smallest acrocentric of the group. The X chromosome was classified as medium submetacentric, it considered atypical for mammals, because X was generally large size metacentric when it compared to the remaining karyotype. The diploid number reduction from 62 to 46 chromosomes may be explained by Robertsonian fusion and the inversion of acrocentric, or even the fission of centromeric regions of metacentric, given that the species Cabassous centralis had 23 acrocentric pairs and that this number was reduced to 14 pairs in the Cabassous tautouay and six pairs in the species described in the present work.