EFAR - Escola de Farmácia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/451

Notícias

O curso de Farmácia em Ouro Preto foi criado em 1839, sendo a mais antiga Escola de Farmácia da América Latina.

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Activity of the new triazole derivative albaconazole against Trypanosoma (Schizotrypanum) cruzi in dog hosts.
(2004) Guedes, Paulo Marcos da Matta; Urbina, Julio Alberto; Lana, Marta de; Afonso, Luís Carlos Crocco; Veloso, Vanja Maria; Tafuri, Washington Luiz; Coelho, George Luiz Lins Machado; Chiari, Egler; Bahia, Maria Terezinha
Albaconazole is an experimental triazole derivative with potent and broad-spectrum antifungal activity and a remarkably long half-life in dogs, monkeys, and humans. In the present work, we investigated the in vivo activity of this compound against two strains of the protozoan parasite Trypanosoma (Schizotrypanum) cruzi, the causative agent of Chagas’ disease, using dogs as hosts. The T. cruzi strains used in the study were previously characterized (murine model) as susceptible (strain Berenice-78) and partially resistant (strain Y) to the drugs currently in clinical use, nifurtimox and benznidazole. Our results demonstrated that albaconazole is very effective in suppressing the proliferation of the parasite and preventing the death of infected animals. Furthermore, the parasitological, PCR, serological, and proliferative assay results indicated parasitological cure indices of 25 and 100% among animals inoculated with T. cruzi strain Y when they were treated with albaconazole at 1.5 mg/kg of body weight/day for 60 and 90 days, respectively. On the other hand, although albaconazole given at 1.5 mg/kg/day was very effective in suppressing the proliferation of the parasite in animals infected with the Berenice-78 T. cruzi strain, no parasitological cure was observed among them, even when a longer treatment period (150 doses) was used. In conclusion, our results demonstrate that albaconazole has trypanocidal activity in vivo and is capable of inducing radical parasitological cure, although natural resistance to this compound was also indicated. Furthermore, the compound can be used in long-term treatment schemes (60 to 150 days) with minimal toxicity and thus represents a potentially useful candidate for the treatment of human Chagas’ disease.
Antigenic extracts of Leishmania braziliensis and Leishmania amazonensis associated with saponin partially protects BALB/c mice against Leishmania chagasi infection by suppressing IL-10 and IL-4 production.
(2010) Grenfell, Rafaella Fortini Queiroz; Silva, Eduardo de Almeida Marques da; Testasicca, Miriam Conceição de Souza; Coelho, Eduardo Antônio Ferraz; Fernandes, Ana Paula Salles Moura; Afonso, Luís Carlos Crocco; Rezende, Simone Aparecida
This study evaluated two vaccine candidates for their effectiveness in protecting BALB/c mice against Leishma¬nia chagasi infection. These immunogenic preparations were composed of Leishmania amazonensis or Leishmania braziliensis antigenic extracts in association with saponin adjuvant. Mice were given three subcutaneous doses of one of these vaccine candidates weekly for three weeks and four weeks later challenged with promastigotes of L. chagasi by intravenous injection. We observed that both vaccine candidates induced a significant reduction in the parasite load of the liver, while the L. amazonensis antigenic extract also stimulated a reduction in spleen parasite load. This protection was associated with a suppression of both interleukin (IL)-10 and IL-4 cytokines by spleen cells in response to L. chagasi antigen. No change was detected in the production of IFN-γ. Our data show that these im-munogenic preparations reduce the type 2 immune response leading to the control of parasite replication.
Emprego da vacinologia reversa para a identificação, triagem e avaliação de peptídeos de L. infantum para o desenho e desenvolvimento de vacinas poliepítopos e de coquetel de peptídeos contra a leishmaniose visceral.
(2018) Brito, Rory Cristiane Fortes de; Reis, Alexandre Barbosa; Resende, Daniela de Melo; Luca, Paula Mello de; Guimarães, Ana Carolina Ramos; Afonso, Luís Carlos Crocco; Reis, Alexandre Barbosa
No contexto de desenvolvimento de vacinas, a vacinologia reversa, ou imunoinformática, é uma abordagem que integra diferentes metodologias computacionais para a busca de alvos e o desenho de vacinas. Assim, a imunoinformática vem se destacando ao permitir o uso de programas para a predição de epítopos imunogênicos in silico. Essa estratégia tem o potencial de buscar alvos para o desenvolvimento de vacinas em todo o proteoma predito de organismos patogênicos. Até a presente data, não existe uma vacina eficaz contra a leishmaniose visceral empregada em campanhas de vacinação. Diante desse cenário, este projeto propõe a utilização da imunoinformática para selecionar epítopos e construir vacinas quiméricas poliepítopos e/ou coquetel de peptídeos a serem testadas contra leishmaniose visceral. No capítulo II desta tese foi apresentado um sistema de predição de epítopos de células T e B, além de vias de sinalização de proteínas. Este sistema foi validado utilizando dados experimentais de proteínas imunogênicas já descritas na literatura, comprovando a existência de uma correlação e associação entre o número de epítopos preditos para células T/B e os resultados experimentais relatados. Em seguida, no capítulo III encontram-se os dados relacionados a duas quimeras poliepítopos que foram desenhadas a partir da abordagem proposta em proteínas imunogênicas já escritas na literatura. Tais quimeras formuladas deram origem a duas vacinas, VAC-1 (quimera A) e VAC-2 (quimera B) ambas associadas ao adjuvante saponina. Assim, foi avaliada a imunogenicidade, a geração de memória imunológica e eficácia das vacinas em camundongos BALB/c submetidos ao protocolo de imunização e desafio com promastigotas de Leishmania infantum. Essas vacinas apresentaram imunogenicidade e capacidade para induzir linfócitos T de memória além de promoverem redução da carga parasitária no baço. Finalmente, no capítulo IV, são mostrados os resultados obtidos de peptídeos imunogênicos identificados através da abordagem de imunoinformática no proteoma predito de L. infantum. Para a seleção destes peptídeos foi realizada uma triagem em cães naturalmente infectados por L. infantum. Estes testes permitiram selecionar os peptídeos que obtiveram melhor performance após o inóculo intradérmico. Assim, foram constituídas as vacinas VAC-3 (coquetel 1) e VAC-4 (coquetel 2) ambas associadas à saponina que foram avaliadas em relação a imunogenicidade, a ativação de células T de memória e a eficácia frente ao desafio com L. infantum. Os resultados obtidos demostraram que a VAC-3 apresentou-se promissora no que se refere a imunogenicidade, indução de memória imunológica de células T e diminuição da carga parasitária no tecido esplênico. Este estudo permitiu certificar e ratificar o potencial da imunoinformática como ferramenta a ser empregada no desenvolvimento de vacinas contra a leishmaniose visceral. Assim sendo, torna-se relevante a realização de maiores estudos para comprovar a real eficácia das vacinas propostas em cães.
Extracellular nucleotide metabolism in Leishmania : influence of adenosine in the establishment of infection.
(2008) Silva, Eduardo de Almeida Marques da; Oliveira, Jamile Camargos de; Figueiredo, Amanda Braga de; Lima Júnior, Djalma de Souza; Carneiro, Cláudia Martins; Fietto, Juliana Lopes Rangel; Afonso, Luís Carlos Crocco
Leishmaniasis is a parasitic disease with a variety of clinical forms, which are related to the Leishmania species involved. In the murine model, Leishmania amazonensis causes chronic non-healing lesions in Leishmania braziliensis- or Leishmania major-resistant mouse strains. In this study, we investigated the involvement of the pathway of extracellular nucleotide hydrolysis, with special focus on the role of extracellular adenosine, in the establishment of Leishmania infection. Our results show that the more virulent parasitedL. Amazonensisdhydrolyzes higher amounts of ATP, ADP and AMP than the two other species, probably due to the higher expression of membrane NTPDase. Corroborating the idea that increased production of adenosine is important to lesion development and establishment of tissue parasitism, we observed that increased 50-nucleotidase activity in L. braziliensis or addition of adenosine at the moment of infection with this parasite resulted in an increase in lesion size and parasitism as well as a delay in lesion healing. Furthermore, inhibition of adenosine receptor A2B led to decreased lesion size and parasitism. Thus, our results suggest that the conversion of ATP, a molecule with pro-inflammatory activity, into adenosine, which possesses immunomodulatory properties, may contribute to the establishment of infection by Leishmania.
IgG isotype profile is correlated with cardiomegaly in Beagle dogs infected with distinct Trypanosoma cruzi strains.
(2008) Guedes, Paulo Marcos da Matta; Veloso, Vanja Maria; Gollob, Kenneth John; Afonso, Luís Carlos Crocco; Caldas, Ivo Santana; Vianna, Priscila; Lana, Marta de; Chiari, Egler; Bahia, Maria Terezinha; Galvão, Lúcia Maria da Cunha
A systematic study following infection by various strains of the protozoan parasite, Trypanosoma cruzi, and the simultaneous monitoring of the humoral immune response together with the elicited cellular response, could add greatly to our understanding of differences between strains of this important human pathogen. In that sense, acute and chronic infections with distinct T. cruzi strains (Y, Berenice-78 and ABC) in Beagle dogs were studied through a longitudinal evaluation of immunoglobulin G (IgG), IgG1 and IgG2 isotypes (by ELISA and flow cytometry (FC)), as well as measurements of peripheral blood mononuclear cell (PBMC) proliferation over a 100-week period, and their correlation with cardiomegaly. Our results show that infected animals presenting cardiomegaly showed lower or absent levels of IgG1 during the chronic phase of the infection, when compared to those that did not show an increase in heart weight. In that manner, our results suggest that IgG1 could be used as a marker for cardiac pathogenicity in Chagas disease.
Intramuscular immunization with p36(LACK) DNA vaccine induces IFN-gama production but does not protect BALB/c mice against Leishmania chagasi intravenous challenge.
(2005) Silva, Eduardo de Almeida Marques da; Coelho, Eduardo Antônio Ferraz; Gomes, Daniel Cláudio de Oliveira; Vilela, Márcia de Carvalho; Masioli, Cássio Zumerle; Tavares, Carlos Alberto Pereira; Fernandes, Ana Paula Salles Moura; Afonso, Luís Carlos Crocco; Rezende, Simone Aparecida
Acute visceral leishmaniasis is a progressive disease caused by Leishmania chagasi in South America. The acquisition of immunity following infection suggests that vaccination is a feasible approach to protect against this disease. Since Leishmania homologue of receptors for activated C kinase (LACK) antigen is of particular interest as a vaccine candidate because of the prominent role it plays in the pathogenesis of experimental Leishmania major infection, we evaluated the potential of a p36(LACK) DNA vaccine in protecting BALB/c mice challenged with L. chagasi. In this study, mice received intramuscular (i.m.) or subcutaneous (s.c.) doses of LACK DNA vaccine. We evaluated the production of vaccine-induced cytokines and whether this immunization was able to reduce parasite load in liver and spleen. We detected a significant production of interferon gamma by splenocytes from i.m. vaccinated mice in response to L. chagasi antigen and to rLACK protein. However, we did not observe a reduction in parasite load neither in liver nor in the spleen of vaccinated animals. The lack of protection observed may be explained by a significant production of IL-10 induced by the vaccine.
Leishmania braziliensis : partial control of experimental infection by Interleukin-12 p40 deficient mice.
(2004) Souza Neto, Sebastião Martins de; Carneiro, Cláudia Martins; Vieira, Leda Quercia; Afonso, Luís Carlos Crocco
Resistance to infection by Leishmania major has been associated with the development of a Th1 type response that is dependent on the presence of interleukin 12 (IL-12). In this work the involvement of this cytokine in the response to infection by L. braziliensis, a less virulent species in the mouse model, was evaluated. Our results show that while interferon (IFN-γ) deficient (-/-) mice inoculated L. braziliensis develop severe uncontrolled lesions, chronic lesions that remained under control up to 12 weeks of infection were observed in IL-12p40 -/- mice. IL 12p40 -/- mice had fewer parasites in their lesions than IFN-γ-/- mice. Lymph node cells from IL-12p40 -/- were capable of producing low but consistent levels of IFN-γ suggestive of its involvement in parasite control. Furthermore, as opposed to previous reports on L. major-infected animals, no switch to a Th2 response was observed in IL- 12p40 -/- infected with L. braziliensis.
Low and high-dose intradermal infection with Leishmania major and Leishmania amazonensis in C57BL/6 mice.
(2010) Côrtes, Denise Fonseca; Carneiro, Matheus Batista Heitor; Santos, Liliane Martins dos; Souza, Talita Correia de Oliveira; Maioli, Tatiani Uceli; Duz, Ana Luiza Cassin; Jorge, Maria Letícia Ramos; Afonso, Luís Carlos Crocco; Carneiro, Cláudia Martins; Vieira, Leda Quercia
A model of skin infection with Leishmania amazonensis with low doses of parasites is compared to infection with high doses of L. amazonensis and low and high doses of Leishmania major. C57BL/6 mice were infected with 103 or 106 parasites in the ear and the outcome of infection was assessed. The appearance of lesions in mice infected with 103 parasites was delayed compared to mice infected with 106 Leishmania and parasites were detectable at the infection site before lesions became apparent. Mice infected with L. amazonensis displayed persistent lesions, whereas infection with L. major spontaneously healed in all groups, although lymphocytes persisted at the site of infection after healing. Macrophages persisted only in L. amazonensis-infected mice. High-dose L. amazonensis-infected mice produced lower levels of IFN-γ and TNF than mice infected with L. major. No correlation between the persistence of parasites and IL-10 levels and the production of nitric oxide or urea by macrophages was found. We conclude that infection with low doses of L. amazonensis in the dermis changes the course of infection by delaying the appearance of lesions. However, low-dose infection does not change the outcomes of susceptibility and cytokine production described for subcutaneous infection with high numbers of parasites.
New lager brewery strains obtained by crossing techniques using cachaça (Brazilian Spirit) yeasts.
(2017) Figueiredo, Bruna Inez Carvalho de; Saraiva, Margarete Alice Fontes; Pimenta, Paloma Patrick de Souza; Testasicca, Miriam Conceição de Souza; Sampaio, Geraldo Magela Santos; Cunha, Aureliano Claret da; Afonso, Luís Carlos Crocco; Queiroz, Marisa Vieira de; Castro, Ieso de Miranda; Brandão, Rogélio Lopes
The development of hybrids has been an effective approach to generate novel yeast strains with optimal technological profile for use in beer production. This study describes the generation of a new yeast strain for lager beer production by direct mating between two Saccharomyces cerevisiae strains isolated from cachaça distilleries: one that was strongly flocculent, and the other with higher production of acetate esters. The first step in this procedure was to analyze the sporulation ability and reproductive cycle of strains belonging to a specific collection of yeasts isolated from cachaça fermentation vats. Most strains showed high rates of sporulation, spore viability, and homothallic behavior. In order to obtain new yeast strains with desirable properties useful for lager beer production, we compare haploid-to-haploid and diploid-to-diploid mating procedures. Moreover, an assessment of parental phenotype traits showed that the segregant diploid C2-1d generated from a diploid-to-diploid mating experiment showed good fermentation performance at low temperature, high flocculation capacity, and desirable production of acetate esters that was significantly better than that of one type lager strain. Therefore, strain C2-1d might be an important candidate for the production of lager beer, with distinct fruit traces and originating using a non-genetically modified organism (GMO) approach.
Successful vaccination against Leishmania chagasi infection in BALB/c mice with freeze-thawed Leishmania antigen and Corynebacterium parvum.
(2007) Vilela, Márcia de Carvalho; Gomes, Daniel Cláudio de Oliveira; Silva, Eduardo de Almeida Marques da; Serafim, Tiago Donatelli; Afonso, Luís Carlos Crocco; Rezende, Simone Aparecida
This study evaluated the potential of a Leishmania antigen vaccine in protecting BALB/c mice against Leishmania chagasi. Mice received two subcutaneous doses of L. amazonensis vaccine with Corynebacterium parvum and subsequent boost was done without adjuvant. One week later, mice were challenged with L. chagasi. We observed that this vaccine caused a significant reduction in parasite load in liver and spleen and induced a high production of IFN-_ and IL-4 by spleen cells from vaccinated mice in response to Leishmania antigen. Together, our data show that this vaccine is capable of inducing a Th1/Th2 response that is important to control parasite replication.
The schistosomiasis spleenOME : unveiling the proteomic landscape of splenomegaly using label-free mass spectrometry.
(2019) Cosenza Contreras, Miguel de Jesus; Castro, Renata Alves de Oliveira e; Mattei, Bruno; Campos, Jonatan Marques; Silva, Gustavo Gonçalves; Paiva, Nívia Carolina Nogueira de; Soares, Rodrigo Dian de Oliveira Aguiar; Carneiro, Cláudia Martins; Afonso, Luís Carlos Crocco; Borges, William de Castro
Schistosomiasis is a neglected parasitic disease that affects millions of people worldwide and is caused by helminth parasites from the genus Schistosoma. When caused by S. mansoni, it is associated with the development of a hepatosplenic disease caused by an intense immune response to the important antigenic contribution of adult worms and to the presence of eggs trapped in liver tissue. Although the importance of the spleen for the establishment of immune pathology is widely accepted, it has received little attention in terms of the molecular mechanisms operating in response to the infection. Here, we interrogated the spleen proteome using a label-free shotgun approach for the potential discovery of molecular mechanisms associated to the peak of the acute phase of inflammation and the development of splenomegaly in the murine model. Over fifteen hundred proteins were identified in both infected and control individuals and 325 of those proteins were differentially expressed. Two hundred and forty-two proteins were found upregulated in infected individuals while 83 were downregulated. Functional enrichment analyses for differentially expressed proteins showed that most of them were categorized within pathways of innate and adaptive immunity, DNA replication, vesicle transport and catabolic metabolism. There was an important contribution of granulocyte proteins and antigen processing and presentation pathways were augmented, with the increased expression of MHC class II molecules but the negative regulation of cysteine and serine proteases. Several proteins related to RNA processing were upregulated, including splicing factors. We also found indications of metabolic reprogramming in spleen cells with downregulation of proteins related to mitochondrial metabolism. Ex-vivo imunophenotyping of spleen cells allowed us to attribute the higher abundance of MHC II detected by mass spectrometry to increased number of macrophages (F4/80+/MHC II+ cells) in the infected condition. We believe these findings add novel insights for the understanding of the immune mechanisms associated with the establishment of schistosomiasis and the processes of immune modulation implied in the host-parasite interactions.