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1.
Biotechnol Prog ; 33(3): 804-814, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28371522

RESUMO

Schistosomiasis is the second leading cause of death due to parasitic diseases in the world. Seeking an alternative for the control of disease, the World Health Organization funded the genome sequencing of the major species related to schistosomiasis to identify potential vaccines and therapeutic targets. Therefore, the aim of this work was to select T and B-cell epitopes from Schistosoma mansoni through computational analyses and evaluate the immunological potential of epitopes in vitro. Extracellular regions of membrane proteins from the Schistosoma mansoni were used to predict promiscuous epitopes with affinity to different human Major Histocompatibility Class II (MHCII) molecules by bioinformatics analysis. The three-dimensional structure of selected epitopes was constructed and used in molecular docking to verify the interaction with murine MHCII H2-IAb . In this process, four epitopes were selected and synthesized to assess their ability to stimulate proliferation of CD4+ T lymphocytes in mice splenocyte cultures. The results showed that Sm041370 and Sm168240 epitopes induced significant cell proliferation. Additionally, the four epitopes were used as antigens in the Indirect Enzyme-Linked Immunosorbent Assay (ELISA) to assess the recognition by serum from individuals infected with Schistosoma mansoni. Sm140560, Sm168240, and Sm041370 epitopes were recognized by infected individuals IgG antibodies. Therefore, Sm041370 and Sm168240 epitopes that stood out in in silico and in vitro analyses could be promising antigens in schistosomiasis vaccine development or diagnostic kits. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:804-814, 2017.


Assuntos
Epitopos/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células/fisiologia , Biologia Computacional/métodos , Ensaio de Imunoadsorção Enzimática , Complexo Principal de Histocompatibilidade/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Schistosoma mansoni/imunologia
2.
J Mol Model ; 22(9): 228, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27568376

RESUMO

The incidence of skin cancer has increased in recent decades, and melanoma is the most aggressive form with the lowest chance of successful treatment. Currently, drug design projects are in progress, but available treatments against metastatic melanoma have not significantly increased survival, and few patients are cured. Thus, new therapeutic agents should be developed as more effective therapeutic options for melanoma. High levels of the BRN2 transcription factor have been related to melanoma development. However, neither the three-dimensional (3D) structure of BRN2 protein nor its POU domain has been determined experimentally. Construction of the BRN2 3D structure, and the study of its interaction with its DNA target, are important strategies for increasing the structural and functional knowledge of this protein. Thus, the aim of this work was to study the interaction between BRN2 and MORE DNA through in silico methods. The full-length BRN2 3D structure was built using the PHYRE2 and Swiss-Model programs, and molecular dynamics of this protein in complex with MORE DNA was simulated for 20 ns by the NAMD program. The BRN2 model obtained includes helix and loop regions, and the BRN2 POU domain shares structural similarity with other members of the transcription factor family. No significant conformational change of this protein occurred during dynamics simulation. These analyses revealed BRN2 residues important for the specific interaction with nucleotide bases and with more than one DNA nucleotide. This study may contribute to the design of inhibitors against BRN2 or MORE DNA as molecular targets of melanoma skin cancer. Graphical Abstract Model of complete Brn2 protein in complex with MORE DNA after building through comparative modeling and refinement by molecular dynamics simulation.


Assuntos
DNA/química , Proteínas de Homeodomínio/química , Melanoma/fisiopatologia , Fatores do Domínio POU/química , Simulação por Computador , Humanos
3.
Appl Biochem Biotechnol ; 179(6): 1023-40, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26979443

RESUMO

Schistosomiasis remains an important parasitic disease that affects millions of individuals worldwide. Despite the availability of chemotherapy, the occurrence of constant reinfection demonstrates the need for additional forms of intervention and the development of a vaccine represents a relevant strategy to control this disease. With the advent of genomics and bioinformatics, new strategies to search for vaccine targets have been proposed, as the reverse vaccinology. In this work, computational analyses of Schistosoma mansoni membrane proteins were performed to predict epitopes with high affinity for different human leukocyte antigen (HLA)-DRB1. Ten epitopes were selected and along with murine major histocompatibility complex (MHC) class II molecule had their three-dimensional structures optimized. Epitope interactions were evaluated against murine MHC class II molecule through molecular docking, electrostatic potential, and molecular volume. The epitope Sm141290 and Sm050890 stood out in most of the molecular modeling analyses. Cellular proliferation assay was performed to evaluate the ability of these epitopes to bind to murine MHC II molecules and stimulate CD4+ T cells showing that the same epitopes were able to significantly stimulate cell proliferation. This work showed an important strategy of peptide selection for epitope-based vaccine design, achieved by in silico analyses that can precede in vivo and in vitro experiments, avoiding excessive experimentation.


Assuntos
Proliferação de Células/genética , Epitopos/imunologia , Schistosoma mansoni/imunologia , Vacinas/imunologia , Animais , Epitopos/genética , Humanos , Proteínas de Membrana/imunologia , Camundongos , Modelos Moleculares , Simulação de Acoplamento Molecular , Schistosoma mansoni/genética , Schistosoma mansoni/patogenicidade , Linfócitos T/imunologia , Vacinas/genética
4.
Gene ; 575(2 Pt 1): 233-43, 2016 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-26341054

RESUMO

The GO-system is a DNA repair mechanism that prevents and corrects oxidative DNA damage. Formamidopyrimidine-DNA glycosylase (FPG/MutM) participates in this system, avoiding the mutagenic effects of 8-oxoguanine lesion into DNA. Corynebacterium pseudotuberculosis, the etiological agent of caseous lymphadenitis, is a facultative intracellular microorganism vulnerable to oxidative DNA damage. Since inefficiencies in the DNA damage repair system can lead to death, the characterization of repair genes may provide valuable molecular targets for caseous lymphadenitis therapy. The purposes of this study were to functionally characterize MutM1 and MutM2 proteins from C. pseudotuberculosis in silico, in vivo, and in vitro and to examine their role in the repair of 8-oxoguanine damage. In silico investigation revealed that both proteins have conserved domains typical of DNA glycosylases, such as DNA binding domains and DNA glycosylase/AP lyase catalytic domain. In comparison with the MutM protein of Escherichia coli, however, CpMutM2 was found to lack residues that are essential for recognizing and excising 8-oxoguanine damage. Molecular docking calculations have shown a native-like orientation of 8-oxoguanine at the CpMutM1 active site, while the same is not observed for CpMutM2, which seems to poorly interact with DNA. Surface charge analyses have corroborated this finding. Overexpression of CpMutM1 or CpMutM2 has toxic effects on E. coli strain BH20 (mutM-), as shown by growth curves obtained in the presence of hydrogen peroxide and cell viability assays. This cytotoxicity can be attributed to an imbalance in the repair pathway, resulting from hyperactivity of DNA glycosylases, leading to formation of AP sites and DNA strand breakage at levels that exceed the processing capacity of other enzymes in the BER pathway. In order to demonstrate the involvement of these enzymes in the recognition and excision of 8-oxoguanine lesion, glycosylase activity was evaluated in vitro. Only the CpMutM1 protein was proven to be capable of recognizing and excising 8-oxoguanine. Taken together, these results suggest that although the formamidopyrimidine-DNA glycosylase domain is conserved in both proteins, only one proved to be functional in recognizing and excising 8-oxoguanine lesion.


Assuntos
Proteínas de Bactérias , Corynebacterium pseudotuberculosis , DNA Bacteriano/metabolismo , DNA-Formamidopirimidina Glicosilase , Genoma Bacteriano , Guanina/análogos & derivados , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Corynebacterium pseudotuberculosis/enzimologia , Corynebacterium pseudotuberculosis/genética , DNA Bacteriano/genética , DNA-Formamidopirimidina Glicosilase/genética , DNA-Formamidopirimidina Glicosilase/metabolismo , Guanina/metabolismo
5.
Cancer Genomics Proteomics ; 12(6): 397-402, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26543086

RESUMO

BACKGROUND: Eosinophil cationic protein (ECP) and eosinophil derived-neurotoxin (EDN) are homologous ribonuclease (RNAse) A family proteins. The objective of the present study was to in silico characterize ECP and EDN with respect to their cytotoxic activities. MATERIALS AND METHODS: Structural, physicochemical, and conserved domain characterizations were carried-out using open-source software, such as InterProScan, NetOGlyc, NetPhos and Discovery Studio 3.1. RESULTS: The proteins did not have atypical conserved domains. EDN had a greater number of glutamine amino acid residues, whereas ECP had a predominance of arginine. ECP had four possible N-glycosylation, three O-glycosylation and four phosphorylation sites. EDN had five putative N-glycosylation, three phosphorylation and no O-glycosylation sites. CONCLUSION: The greater cationicity of ECP may be related to its higher cytotoxicity and to the fact that the varying post-translational modification profiles can generate functional differences from structural alteration. In vivo and in vitro studies need to be performed in order to confirm these predictions.


Assuntos
Proteína Catiônica de Eosinófilo/metabolismo , Neurotoxina Derivada de Eosinófilo/metabolismo , Regulação da Expressão Gênica , Arginina/química , Biologia Computacional , Bases de Dados de Proteínas , Glutamina/química , Glicosilação , Humanos , Processamento de Proteína Pós-Traducional , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Ribonuclease Pancreático/química , Software
6.
Recurso educacional aberto em Português | CVSP - Brasil | ID: una-1929

RESUMO

Este material compõe a disciplina obrigatória " Modelo de atenção à saúde" do Curso de Especialização Estratégia Saúde da Família (2014). Pretende-se com esta disciplina estimular uma reflexão sobre os modelos assistências em saúde, em diferentes contextos e em diferentes momentos históricos, e os principais determinantes da evolução histórica. Tratar em particular do Sistema Único de Saúde (SUS) e da estratégia Saúde da Família (ESF), entendida como projeto de reorganização da Atenção Básica de Saúde (ABS) e de implementação do novo modelo assistencial que está expresso na Constituição. Abordar ainda o trabalho da equipe de Saúde da Família no esforço de reorientação da ABS e de mudança de modelo assistencial. A disciplina está organizada em quatro unidades: - Unidade 1 - apresenta uma discussão dos modelos assistenciais em saúde no Brasil; - Unidade 2 - discute a estratégia de Saúde da Família no âmbito da reorganização da Atenção Básica à Saúde; - Unidade 3 - aborda a determinação social dos indivíduos e do processo saúde-doença; - Unidade 4 - apresentada a proposta de atenção centrada na pessoa e o cuidado em saúde.


Assuntos
Saúde da Família , Atenção à Saúde , Estratégias de Saúde Nacionais , Política de Saúde
7.
Infect Genet Evol ; 20: 83-95, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23973434

RESUMO

Schistosomiasis is a serious public health problem in Brazil and worldwide. Although the drugs used to treatment schistosomiasis are effective, the disease continues to expand in all endemic countries due to constant reinfection, poor sanitation, and the lack of effective programs for disease control. However, advances generated through genome projects have provided important information that has improved the understanding of the biology of this parasite. These advances, associated with the advent of bioinformatic analysis, are becoming an important tool in reverse vaccinology. Through database access to the DNA and protein sequences of Schistosoma mansoni and the use of bioinformatics programs, fourteen epitopes were identified. Five epitopes were obtained from proteins whose immunogenic potential had already been assessed in other studies (KP), and nine whose immunogenic potential is unknown (UP). To improve stimulation of the host immune system, the selected epitopes were modeled with a sugar moiety. After this addition, all of the epitopes showed structures similar to those observed in the native proteins, but only eleven of the peptides presented thermodynamically stable structures. Prediction analysis and molecular modeling showed that the glycopeptides presented here are important targets in the search for a vaccine against schistosomiasis. Additionally, they suggest that these molecules may be used in immunological assays to evaluate the level of protection, the effect on pathology reduction and the profile of cytokines and antibodies induced by them.


Assuntos
Epitopos/imunologia , Vacinas Protozoárias/imunologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/prevenção & controle , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/imunologia , Antígenos de Helmintos/genética , Antígenos de Helmintos/imunologia , Biologia Computacional , Bases de Dados de Ácidos Nucleicos , Bases de Dados de Proteínas , Epitopos/genética , Proteínas de Helminto/genética , Proteínas de Helminto/imunologia , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Schistosoma mansoni/genética , Esquistossomose mansoni/genética , Esquistossomose mansoni/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia
8.
Cien Saude Colet ; 15(1): 171-83, 2010 Jan.
Artigo em Português | MEDLINE | ID: mdl-20169244

RESUMO

This paper aims to evaluate the nineteen years of the National Health System in Brazil, under the prism of equity. It takes into account the current political context in Brazil in the 80s, that the democratization of the country and the health sector could, per se, lead to a more equitable situation regarding the access to health services. Democracy and equity concepts are here discussed; analyzing which situations may facilitate or make it difficult its association in a theoretical plan, applying them to the Brazilian context in a more general form and, to emphasizing practical implications to the National Health System and to groups of activism related to health reforms. It also seeks to show the limits and possibilities of these groups with regards to the reduction of inequality, in relation to the access to health services, which still remain. To conclude, the author points out the need for other movements to be established which seek the reduction of such and other inequalities, such as access to education, housing, etc, drawing special attention to the role played by the State, which is questioned regarding its incapacity of promoting equity, once it presents itself as being powerful when approaching other matters.


Assuntos
Democracia , Reforma dos Serviços de Saúde , Programas Nacionais de Saúde , Brasil , Reforma dos Serviços de Saúde/normas , Programas Nacionais de Saúde/normas , Fatores Socioeconômicos , Fatores de Tempo
9.
Ciênc. Saúde Colet. (Impr.) ; 15(1): 171-183, jan. 2010.
Artigo em Português | LILACS | ID: lil-538941

RESUMO

Este artigo procura avaliar os dezenove anos da implementação do Sistema Único de Saúde (SUS) no Brasil sob o prisma da equidade. Toma como ponto de partida um contexto de expectativas vigentes nos anos oitenta do século XX de que a democratização do país e do setor saúde pudesse, por si, levar a uma situação mais equitativa em relação ao acesso a serviços de saúde. Discute os conceitos de democracia e equidade, analisando que situações podem facilitar ou dificultar sua associação no plano teórico, aplicando-os ao contexto brasileiro de forma mais geral e aos movimentos pela reforma sanitária e implementação do SUS em particular. Procura também evidenciar os limites e as possibilidades destes movimentos no que tange à redução das desigualdades no acesso a serviços de saúde que ainda persistem. A conclusão aponta a necessidade de que se estabeleçam outros movimentos que busquem a redução destas e de outras desigualdades, como o acesso á educação, moradia, etc., chamando a atenção, em especial, para o papel do Estado, que é questionado em sua pretensa debilidade para promover justiça social, uma vez que se mostra muito potente quando aborda outras questões.


This paper aims to evaluate the nineteen years of the National Health System in Brazil, under the prism of equity. It takes into account the current political context in Brazil in the 80s, that the democratization of the country and the health sector could, per se, lead to a more equitable situation regarding the access to health services. Democracy and equity concepts are here discussed; analyzing which situations may facilitate or make it difficult its association in a theoretical plan, applying them to the Brazilian context in a more general form and, to emphasizing practical implications to the National Health System and to groups of activism related to health reforms. It also seeks to show the limits and possibilities of these groups with regards to the reduction of inequality, in relation to the access to health services, which still remain. To conclude, the author points out the need for other movements to be established which seek the reduction of such and other inequalities, such as access to education, housing, etc, drawing special attention to the role played by the State, which is questioned regarding its incapacity of promoting equity, once it presents itself as being powerful when approaching other matters.


Assuntos
Democracia , Reforma dos Serviços de Saúde , Programas Nacionais de Saúde , Brasil , Reforma dos Serviços de Saúde/normas , Programas Nacionais de Saúde/normas , Fatores Socioeconômicos , Fatores de Tempo
10.
Recurso educacional aberto em Português | CVSP - Brasil | ID: una-92

RESUMO

Propõe-se nesse módulo estimular uma reflexão sobre os modelos assistenciais em saúde em diferentes contextos, situando, no caso do Brasil, a sua evolução em diferentes momentos históricos e os principais determinantes dessa evolução. Trata-se em particular do Sistema Único de Saúde e da Estratégia de Saúde da Família, entendida como projeto de reorganização da Atenção Básica e de implementação do novo Modelo Assistencial que está expresso na Constituição Brasileira. Aborda-se ainda o trabalho da Equipe de Saúde da Família no esforço de reorientação da ABS e de mudança de Modelo Assistencial.


Assuntos
Saúde da Família , Estratégias de Saúde Nacionais , Política de Saúde
11.
Brasília méd ; 45(3): 244-249, 2008. tab
Artigo em Português | LILACS | ID: lil-528136

RESUMO

Os adenomas hipofisários familiares são condição rara, cuja descrição inicial foi em neoplasia endócrina múltipla tipo 1 e em complexo de Carney, doenças provocadas por mutações nos genes MEN1 e PRKAR1A respectivamente. O somatotropinoma familiar isolado é também uma síndrome clínica bem descrita, relacionada exclusivamente em pacientes com acrogigantismo. Os adenomas hipofisários de todos os tipos - não limitados aos somatotropinomas - podem ocorrer em cenário familiar na ausência do MEN1 e do complexo de Carney. Este fenótipo é denominado adenomas hipofisários familiares isolados. Nesses adenomas, os fenótipos do adenoma da hipófise, seja homogêneo ou heterogêneo, podem ocorrer em famílias. Os casos de adenomas hipofisários familiares isolados diferem do MEN1 em termos de baixa proporção de prolactinomas e maior frequência de somatotropinomas no coorte desses adenomas. Pacientes com esta doença são mais jovens e têm prolactinomas com maiores dimensões que aqueles portadores de adenoma hipofisário esporádico. A minoria das famílias com esses adenomas hipofisários (15%) trazem mutação no gene que codifica a proteína interatuante-receptora do aril-hidrocarboneto (aryl hydrocarbon receptor interacting protein AIP). Mutações nessa proteína estão presentes em somente metade dos casos de somatotropinoma familiar isolado, ocorrendo como parte dos coortes de adenomas hipofisários familiares isolados. Em famílias com mutações no gene da AIP, os adenomas hipofisários estão em fase invasiva em mais de 50% dos casos. Tais mutações são extremamente raras em pacientes com adenoma hipofisário esporádico. Esta revisão trata de adenomas hipofisários de origem familiar, em que se descrevem em detalhes os achados clínicos, patológicos e genéticos dessa afecção e direciona aspectos da abordagem clínica das famílias com a anomalia, portadoras ou não de mutações no gene AIP.


Familial pituitary adenomas are a rare condition and was firstly described in multiple endocrine neoplasia type 1(MEN1) and Carney's complex, which occur due to mutations in the genes MEN1 and PRKAR1A, respectively. Isolated familial somatotropinoma is also a well-described clinical syndrome related only to patients with acrogigantism. Pituitary adenomas of all types - not limited to isolated familial somatotropinoma - can occur in a familial setting in the absence of MEN1 and Carney's complex; this phenotype is termed familial isolated pituitary adenomas (FIPA). In these adenomas both homogeneous and heterogeneous pituitary adenoma phenotypes can occur within families. These adenomas differs from MEN1 in terms of a lower proportion of prolactinomas and more frequent somatotropinomas in the FIPA cohort. Patients with familial isolated pituitary adenomas are significantly younger at diagnosis and have significantly larger pituitary adenomas than matched sporadic pituitary adenoma counterparts. A minority of FIPA families overall (15%) exhibit mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene; AIP mutations are present in only half of isolated familial somatotropinoma kindreds occurring as part of the FIPA cohort. In families with AIP mutations, pituitary adenomas have a penetrance of over 50%. AIP mutations are extremely rare in patients with sporadic pituitary adenomas. This review deals with pituitary adenomas that occur in a familial setting, describes in detail the clinical, pathological and genetic features of familial isolated pituitary adenomas and addresses aspects of the clinical approach to FIPA families with and without AIP mutations.


Assuntos
Humanos , Adenoma , Hipófise , Neoplasias Hipofisárias , Sinais e Sintomas
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