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Search Results: 1 - 10 of 1518 matches for " Sabrina Epiphanio "
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Unlike the synchronous Plasmodium falciparum and P. chabaudi infection, the P. berghei and P. yoelii asynchronous infections are not affected by melatonin
Piero Bagnaresi,Eduardo Alves,Henrique Borges da Silva,Sabrina Epiphanio
International Journal of General Medicine , 2009,
Abstract: Piero Bagnaresi1, Eduardo Alves1, Henrique Borges da Silva1, Sabrina Epiphanio2, Maria M Mota2, Célia RS Garcia11Departamento de Fisiologia, Instituto de Biociências, Universidade de S o Paulo, S o Paulo, Brazil; 2Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, PortugalAbstract: We have previously reported that Plasmodium chabaudi and P. falciparum sense the hormone melatonin and this could be responsible for the synchrony of malaria infection. In P. chabaudi and P. falciparum, melatonin induces calcium release from internal stores, and this response is abolished by U73122, a phospholipase C inhibitor, and luzindole, a melatoninreceptor competitive antagonist. Here we show that, in vitro, melatonin is not able to modulate cell cycle, nor to elicit an elevation in intracellular calcium concentration of the intraerythrocytic forms of P. berghei or P. yoelii, two rodent parasites that show an asynchrononous development in vivo. Interestingly, melatonin and its receptor do not seem to play a role during hepatic infection by P. berghei sporozoites either. These data strengthen the hypothesis that hostderived melatonin does not synchronize malaria infection caused by P. berghei and P. yoelii. Moreover, these data explain why infections by these parasites are asynchronous, contrary to what is observed in P. falciparum and P. chabaudi infections.Keywords: malaria, calcium, melatonin, cell cycle, rhythm, sporozoite
A Small Molecule Inhibitor of Signal Peptide Peptidase Inhibits Plasmodium Development in the Liver and Decreases Malaria Severity
Iana Parvanova, Sabrina Epiphanio, Abdul Fauq, Todd E. Golde, Miguel Prudêncio, Maria M. Mota
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0005078
Abstract: The liver stage of Plasmodium's life cycle is the first, obligatory step in malaria infection. Decreasing the hepatic burden of Plasmodium infection decreases the severity of disease and constitutes a promising strategy for malaria prophylaxis. The efficacy of the gamma-secretase and signal peptide peptidase inhibitor LY411,575 in targeting Plasmodium liver stages was evaluated both in human hepatoma cell lines and in mouse primary hepatocytes. LY411,575 was found to prevent Plasmodium's normal development in the liver, with an IC50 of approximately 80 nM, without affecting hepatocyte invasion by the parasite. In vivo results with a rodent model of malaria showed that LY411,575 decreases the parasite load in the liver and increases by 55% the resistance of mice to cerebral malaria, one of the most severe malaria-associated syndromes. Our data show that LY411,575 does not exert its effect via the Notch signaling pathway suggesting that it may interfere with Plasmodium development through an inhibition of the parasite's signal peptide peptidase. We therefore propose that selective signal peptide peptidase inhibitors could be potentially used for preventive treatment of malaria in humans.
Toxoplasmosis in emperor tamarin (Saguinus imperator): case report
EPIPHANIO, Sabrina;CAT?O-DIAS, José Luiz;GUIMAR?ES, Marcelo Alcindo de Barros Vaz;
Brazilian Journal of Veterinary Research and Animal Science , 1999, DOI: 10.1590/S1413-95961999000200003
Abstract: a case of toxoplasmosis in an adult male emperor tamarin (saguinus imperator) is reported. the primate was found dead and no clinical sign was noticed before death. pathological findings included moderate to severe interstitial pneumonia, multifocal necrotizing hepatitis and multifocal to coalescing necrotizing lymphadenitis. immunohistochemistry assays (strepto-avidin-biotin-peroxidase) performed on paraffin embedded tissues (lung, lymph nodes, liver, spleen, heart, intestine and adipose tissue) were strongly positive for toxoplasma gondii.
Unlike the synchronous Plasmodium falciparum and P. chabaudi infection, the P. berghei and P. yoelii asynchronous infections are not affected by melatonin
Piero Bagnaresi, Eduardo Alves, Henrique Borges da Silva, Sabrina Epiphanio, Maria M Mota, Célia RS Garcia
International Journal of General Medicine , 2009, DOI: http://dx.doi.org/10.2147/IJGM.S3699
Abstract: like the synchronous Plasmodium falciparum and P. chabaudi infection, the P. berghei and P. yoelii asynchronous infections are not affected by melatonin Original Research (3714) Total Article Views Authors: Piero Bagnaresi, Eduardo Alves, Henrique Borges da Silva, Sabrina Epiphanio, Maria M Mota, Célia RS Garcia Published Date April 2009 Volume 2009:2 Pages 47 - 55 DOI: http://dx.doi.org/10.2147/IJGM.S3699 Piero Bagnaresi1, Eduardo Alves1, Henrique Borges da Silva1, Sabrina Epiphanio2, Maria M Mota2, Célia RS Garcia1 1Departamento de Fisiologia, Instituto de Biociências, Universidade de S o Paulo, S o Paulo, Brazil; 2Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal Abstract: We have previously reported that Plasmodium chabaudi and P. falciparum sense the hormone melatonin and this could be responsible for the synchrony of malaria infection. In P. chabaudi and P. falciparum, melatonin induces calcium release from internal stores, and this response is abolished by U73122, a phospholipase C inhibitor, and luzindole, a melatoninreceptor competitive antagonist. Here we show that, in vitro, melatonin is not able to modulate cell cycle, nor to elicit an elevation in intracellular calcium concentration of the intraerythrocytic forms of P. berghei or P. yoelii, two rodent parasites that show an asynchrononous development in vivo. Interestingly, melatonin and its receptor do not seem to play a role during hepatic infection by P. berghei sporozoites either. These data strengthen the hypothesis that hostderived melatonin does not synchronize malaria infection caused by P. berghei and P. yoelii. Moreover, these data explain why infections by these parasites are asynchronous, contrary to what is observed in P. falciparum and P. chabaudi infections.
Recrudescent Plasmodium berghei from Pregnant Mice Displays Enhanced Binding to the Placenta and Induces Protection in Multigravida
Claudio R. F. Marinho, Rita Neres, Sabrina Epiphanio, Lígia A. Gon?alves, Manuela Beir?o Catarino, Carlos Penha-Gon?alves
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0005630
Abstract: Pregnancy-associated malaria (PAM) is associated with placenta pathology and poor pregnancy outcome but the mechanisms that control the malaria parasite expansion in pregnancy are still poorly understood and not amenable for study in human subjects. Here, we used a set of new tools to re-visit an experimental mouse model of pregnancy-induced malaria recrudescence, BALB/c with chronic Plasmodium berghei infection. During pregnancy 60% of the pre-exposed primiparous females showed pregnancy-induced malaria recrudescence and we demonstrated that the recrudescent P. berghei show an unexpected enhancement of the adherence to placenta tissue sections with a marked specificity for CSA. Furthermore, we showed that the intensity of parasitemia in primigravida was quantitatively correlated with the degree of thickening of the placental tissue and up-regulation of inflammation-related genes such as IL10. We also confirmed that the incidence of pregnancy-induced recrudescence, the intensity of the parasitemia peak and the impact on the pregnancy outcome decreased gradually from the first to the third pregnancy. Interestingly, placenta pathology and fetal impairment were also observed at low frequency among non-recrudescent females. Together, the data raise the hypothesis that recrudescent P. berghei displays selected specificity for the placenta tissue enabling on one hand, the triggering of the pathological process underlying PAM and on the other hand, the induction of PAM protection mechanisms that are revealed in subsequent pregnancies. Thus, by exploiting P. berghei pregnancy-induced recrudescence, this experimental system offers a mouse model to study the susceptibility to PAM and the mechanisms of disease protection in multigravida.
Detection of anti-Toxoplasma gondii antibodies in experimentally and naturally infected non-human primates by Indirect Fluorescence Assay (IFA) and indirect ELISA
Bouer, Andréa;Werther, Karin;Machado, Rosangela Zacarias;Nakaghi, Andréa Cristina Higa;Epiphanio, Sabrina;Cat?o-Dias, José Luiz;
Revista Brasileira de Parasitologia Veterinária , 2010, DOI: 10.4322/rbpv.01901005
Abstract: the indirect fluorescence assay (ifa) and the indirect elisa were comparatively used to detect igg and igm antibodies for toxoplasma gondii in experimentally and naturally infected primates. in the experimentally infected group, antibodies of diagnostic value were detected at day 9 post-infection (pi) with the ifa (igg and igm) and with igg-elisa. igm-elisa detected antibodies for t. gondii starting at day 3 pi until the end of the experiment (102 days pi). of the 209 naturally infected sera tested, from many zoos of state of sao paulo, 64.59 and 67.94% were positive in the igg-ifa test and igg-elisa respectively. igm-elisa test detected seropositivity in 52.63% of the sera although igm-ifa test detected it in only in 0.96% of the samples. the differential toxoplasmosis diagnosis was accomplished with neospora caninum by ifa, observing 61 (29.2%) seropositive animals for this parasite and 149 (70.8%) negative. sixty animals were positive for both t. gondii and n. caninum. pneumonia, splenomegaly, and intestinal ulcers were macroscopically observed. unremarkable interstitial pneumonia, enteritis, colitis, splenitis, and glomerulitis were microscopically observed. the immunohistochemical stain could not detect the presence of t. gondii in the tissues of the animals infected experimentally.
Human Resources Information System (HRIS): A Theoretical Perspective  [PDF]
Sabrina Sabrina Jahan
Journal of Human Resource and Sustainability Studies (JHRSS) , 2014, DOI: 10.4236/jhrss.2014.22004
Abstract: HRIS is one of the major modern HR tools. In developed countries, it became popular since the be-ginning of this century. In Bangladesh, corporate organizations have started to implement HRIS in last 5 years. But still its implementation is limited within the big corporate houses. Small corporate houses and public organizations have failed to realize the benefits of HRIS and taken hardly any initiative to implement the system. The major barrier to success of HRIS is the lack of management commitment. The major limitation is the high cost. But the benefits of the HRIS are more than the limitations. Once it is implemented in any organization, employees and management have accepted and realized the benefits. But to get it implemented is a challenge. This study is an attempt to provide a theoretical analysis of the HRIS implementation with analysis of benefits, limitations and barriers. A case study was prepared to provide a better understanding of the topic in a real life context.
Conflitos vivenciados por atletas quanto à manuten??o da prática esportiva de alto rendimento
Epiphanio, Erika H?fling;
Estudos de Psicologia (Campinas) , 2002, DOI: 10.1590/S0103-166X2002000100002
Abstract: the study here reported investigated the conflicts experienced by young athletes with respect in maintaining sport practice as a priority activity in their lives. it was developed when factors indicating the presence of these conflicts were identified during the psychological follow-up of a volley-ball team composed by seventeen female players and of ten athletes performing individual sports. on average, these subjects had eighteen years of age. the facts concerning the phenomena here investigated were collected during their psychological follow-up, that lasted from a minimum of four months to a maximum of two years, weekly psychological interventions taking place with all athletes enrolled in this study. the follow-up sessions were centered on reflections about sport practice and took place individually, on the basis of a single session per hour per week, with the exception of volley-ball athletes, who attended a weekly group session, their members being occasionally consulted individually. this study showed that at certain stage of one's life conflicts commonly occur in relation to the concern for sports. these conflicts are possibly related to the general lack of objectives and to the poor perspectives in sport career, factors that interact with the progressive fading of the pleasures its practice originally brings. the degree of involvement necessary to become a high performing athlete also seems to play an important role in the origin of these conflicts. this conflictive situation originates normally during adolescence, among the many that commonly arise at this age. this moment is however important, because it is during that pressure for choosing an athlete's life takes place. this is explained, on its turn, by the fact that the sports carrer is a short one, specially devised for young people. all the above-mentioned findings indicate important points of therapeutic attention for the psychologist involved with athletes and sport practice.
Psicologia do esporte: apropriando a desapropria o
Erika H?fling Epiphanio
Psicologia: Ciência e Profiss?o , 1999, DOI: 10.1590/s1414-98931999000300008
Abstract:
Placental Histopathological Changes Associated with Plasmodium vivax Infection during Pregnancy
Rodrigo M. Souza equal contributor,Ricardo Ataíde equal contributor,Jamille G. Dombrowski,Vanessa Ippólito,Elizabeth H. Aitken,Suiane N. Valle,José M. álvarez,Sabrina Epiphanio,Claudio R. F. Marinho
PLOS Neglected Tropical Diseases , 2013, DOI: 10.1371/journal.pntd.0002071
Abstract: Histological evidence of Plasmodium in the placenta is indicative of placental malaria, a condition associated with severe outcomes for mother and child. Histological lesions found in placentas from Plasmodium-exposed women include syncytial knotting, syncytial rupture, thickening of the placental barrier, necrosis of villous tissue and intervillositis. These histological changes have been associated with P. falciparum infections, but little is known about the contribution of P. vivax to such changes. We conducted a cross-sectional study with pregnant women at delivery and assigned them to three groups according to their Plasmodium exposure during pregnancy: no Plasmodium exposure (n = 41), P. vivax exposure (n = 59) or P. falciparum exposure (n = 19). We evaluated their placentas for signs of Plasmodium and placental lesions using ten histological parameters: syncytial knotting, syncytial rupture, placental barrier thickness, villi necrosis, intervillous space area, intervillous leucocytes, intervillous mononucleates, intervillous polymorphonucleates, parasitized erythrocytes and hemozoin. Placentas from P. vivax-exposed women showed little evidence of Plasmodium or hemozoin but still exhibited more lesions than placentas from women not exposed to Plasmodium, especially when infections occurred twice or more during pregnancy. In the Brazilian state of Acre, where diagnosis and primary treatment are readily available and placental lesions occur in the absence of detected placental parasites, relying on the presence of Plasmodium in the placenta to evaluate Plasmodium-induced placental pathology is not feasible. Multivariate logistic analysis revealed that syncytial knotting (odds ratio [OR], 4.21, P = 0.045), placental barrier thickness (OR, 25.59, P = 0.021) and mononuclear cells (OR, 4.02, P = 0.046) were increased in placentas from P. vivax-exposed women when compared to women not exposed to Plasmodium during pregnancy. A vivax-score was developed using these three parameters (and not evidence of Plasmodium) that differentiates between placentas from P. vivax-exposed and unexposed women. This score illustrates the importance of adequate management of P. vivax malaria during pregnancy.
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