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101.
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Mariana Matera Veras Karina do Valle Marques Maria Angélica Miglino Elia Garcia Caldini 《American journal of primatology》2009,71(2):145-152
Alouatta guariba clamitans (brown howler monkey) is an endemic primate from the southeastern Brazil tropical forests, classified as near threatened by the IUCN Red List 2007. The genus Alouatta is one of the most difficult New World monkeys to breed and rear in captivity. In this study we examined the macroscopic and histological aspects of the female genital tract of wild brown howler monkeys to provide baseline information for future reproduction research. The anatomical relationship between the vagina, uterus, broad ligament, oviducts and ovaries are those of a typical primate reproductive tract. The fundic portion of the uterus is globoid, the cervix is well developed, which confers to the uterus an elongated shape, and the vagina is a long flattened channel. Histological analysis conducted in females in the follicular phase revealed large quantities of interstitial luteinized tissue in the ovaries, a stratified nonkeratinized vaginal epithelium, lack of glands in the vaginal mucosa and simple tubular endometrial glands. The observed anatomical features should be considered in the adaptation and application of assisted reproductive techniques aimed at improving captive reproduction for species conservation. Am. J. Primatol. 71:145–152, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
103.
Malal M. Diop Nicolas Moiroux Fabrice Chandre Hadrien Martin-Herrou Pascal Milesi Olayidé Boussari Angélique Porciani Stéphane Duchon Pierrick Labbé Cédric Pennetier 《PloS one》2015,10(4)
In response to the widespread use of control strategies such as Insecticide Treated Nets (ITN), Anopheles mosquitoes have evolved various resistance mechanisms. Kdr is a mutation that provides physiological resistance to the pyrethroid insecticides family (PYR). In the present study, we investigated the effect of the Kdr mutation on the ability of female An. gambiae to locate and penetrate a 1cm-diameter hole in a piece of netting, either treated with insecticide or untreated, to reach a bait in a wind tunnel. Kdr homozygous, PYR-resistant mosquitoes were the least efficient at penetrating an untreated damaged net, with about 51% [39-63] success rate compared to 80% [70-90] and 78% [65-91] for homozygous susceptible and heterozygous respectively. This reduced efficiency, likely due to reduced host-seeking activity, as revealed by mosquito video-tracking, is evidence of a recessive behavioral cost of the mutation. Kdr heterozygous mosquitoes were the most efficient at penetrating nets treated with PYR insecticide, thus providing evidence for overdominance, the rarely-described case of heterozygote advantage conveyed by a single locus. The study also highlights the remarkable capacity of female mosquitoes, whether PYR-resistant or not, to locate holes in bed-nets. 相似文献
104.
Moffitt’s theory of delinquency suggests that at-risk youths can be divided into two groups, the adolescence- limited group and the life-course-persistent group, predetermined at a young age, and social interactions between these two groups become important during the adolescent years. We built an agent-based model based on the microscopic interactions Moffitt described: (i) a maturity gap that dictates (ii) the cost and reward of antisocial behavior, and (iii) agents imitating the antisocial behaviors of others more successful than themselves, to find indeed the two groups emerging in our simulations. Moreover, through an intervention simulation where we moved selected agents from one social network to another, we also found that the social network plays an important role in shaping the life course outcome. 相似文献
105.
Angélica F. Arcanjo Isabel F. LaRocque-de-Freitas Juliana Dutra B. Rocha Daniel Zamith Ana Caroline Costa-da-Silva Marise Pinheiro Nunes Fabio P. Mesquita-Santos Alexandre Morrot Alessandra A. Filardy Mario Mariano Christianne Bandeira-Melo George A. DosReis Debora Decote-Ricardo Célio Geraldo Freire-de-Lima 《PloS one》2015,10(5)
B-1 cells can be differentiated from B-2 cells because they are predominantly located in the peritoneal and pleural cavities and have distinct phenotypic patterns and activation properties. A mononuclear phagocyte derived from B-1 cells (B-1CDP) has been described. As the B-1CDP cells migrate to inflammatory/infectious sites and exhibit phagocytic capacity, the microbicidal ability of these cells was investigated using the Leishmania major infection model in vitro. The data obtained in this study demonstrate that B-1CDP cells are more susceptible to infection than peritoneal macrophages, since B-1CDP cells have a higher number of intracellular amastigotes forms and consequently release a larger number of promastigotes. Exacerbated infection by L. major required lipid bodies/PGE2 and IL-10 by B-1CDP cells. Both infection and the production of IL-10 were decreased when PGE2 production was blocked by NSAIDs. The involvement of IL-10 in this mechanism was confirmed, since B-1CDP cells from IL-10 KO mice are more competent to control L. major infection than cells from wild type mice. These findings further characterize the B-1CDP cells as an important mononuclear phagocyte that plays a previously unrecognized role in host responses to L. major infection, most likely via PGE2-driven production of IL-10. 相似文献
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Angélica R. Cappellari Micheli M. Pillat Hellio D. N. Souza Fabrícia Dietrich Francine H. Oliveira Fabrício Figueiró Ana L. Abujamra Rafael Roesler Joanna Lecka Jean Sévigny Ana Maria O. Battastini Henning Ulrich 《PloS one》2015,10(10)
Background
Ecto-5’-nucleotidase/CD73 (ecto-5’-NT) participates in extracellular ATP catabolism by converting adenosine monophosphate (AMP) into adenosine. This enzyme affects the progression and invasiveness of different tumors. Furthermore, the expression of ecto-5’-NT has also been suggested as a favorable prognostic marker, attributing to this enzyme contradictory functions in cancer. Medulloblastoma (MB) is the most common brain tumor of the cerebellum and affects mainly children.Materials and Methods
The effects of ecto-5’-NT overexpression on human MB tumor growth were studied in an in vivo model. Balb/c immunodeficient (nude) 6 to 14-week-old mice were used for dorsal subcutaneous xenograph tumor implant. Tumor development was evaluated by pathophysiological analysis. In addition, the expression patterns of adenosine receptors were verified.Results
The human MB cell line D283, transfected with ecto-5’-NT (D283hCD73), revealed reduced tumor growth compared to the original cell line transfected with an empty vector. D283hCD73 generated tumors with a reduced proliferative index, lower vascularization, the presence of differentiated cells and increased active caspase-3 expression. Prominent A1 adenosine receptor expression rates were detected in MB cells overexpressing ecto-5’-NT.Conclusion
This work suggests that ecto-5’-NT promotes reduced tumor growth to reduce cell proliferation and vascularization, promote higher differentiation rates and initiate apoptosis, supposedly by accumulating adenosine, which then acts through A1 adenosine receptors. Therefore, ecto-5’-NT might be considered an important prognostic marker, being associated with good prognosis and used as a potential target for therapy. 相似文献109.
110.
Said El?Shamieh Marion Neuillé Angélique Terray Elise Orhan Christel Condroyer Vanessa Démontant Christelle Michiels Aline Antonio Fiona Boyard Marie-Elise Lancelot Mélanie Letexier Jean-Paul Saraiva Thierry Léveillard Saddek Mohand-Sa?d Olivier Goureau José-Alain Sahel Christina Zeitz Isabelle Audo 《American journal of human genetics》2014,94(4):625-633