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1.
Comput Biol Chem ; 94: 107563, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34425495

RESUMO

The Multiple Sequence Alignment (MSA) is a key task in bioinformatics, because it is used in different important biological analysis, such as function and structure prediction of unknown proteins. There are several approaches to perform MSA and the use of metaheuristics stands out because of the search ability of these methods, which generally leads to good results in a reasonable amount of time. This paper presents a Systematic Literature Review (SLR) on metaheuristics for MSA, compiling relevant works published between 2014 and 2019. The results of our SLR show the constant interest in this subject, due to the several recent publications that use different metaheuristics to obtain more accurate alignments. Moreover, the final results of our SLR show a multi-objective and hybrid approaches trends, which generally leads these methods to achieve even better results. Thus, we show in this work how the use of metaheuristics to perform MSA still remains an important and promising open research field.


Assuntos
Algoritmos , Biologia Computacional , Alinhamento de Sequência
2.
Braz J Microbiol ; 50(1): 147-155, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30637644

RESUMO

BACKGROUND: Hepatitis C virus (HCV) infection is associated with chronic liver disease, resulting in cirrhosis and hepatocellular carcinoma. Approximately 20% of HCV infections are spontaneously resolved. Here, we assessed the hierarchical relevance of host factors contributing to viral clearance. METHODS: DNA samples from 40 resolved infections and 40 chronic HCV patients paired by age were analyzed. Bivariate analysis was performed to rank the importance of each contributing factor in spontaneous HCV clearance. RESULTS: Interestingly, 63.6% of patients with resolved infections exhibited the protective genotype CC for SNP rs12979860. Additionally, 59.3% of patients with resolved infections displayed the protective genotype TT/TT for SNP ss469415590. Moreover, a ranking of clearance factors was estimated. In order of importance, the IL28B CC genotype (OR 0.197, 95% CI 0.072-0.541) followed by the INFL4 TT/TT genotype (OR 0.237, 95% CI 0.083-0.679), and female gender (OR 0.394, 95% CI 0.159-0.977) were the main predictors for clearance of HCV infection. CONCLUSIONS: HCV clearance is multifactorial and the contributing factors display a hierarchical order. Identifying all elements playing role in HCV clearance is of the most importance for HCV-related disease management. Dissecting the relevance of each contributing factor will certainly improve our understanding of the pathogenesis of HCV infection.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/virologia , Adulto , Anticorpos Antivirais/imunologia , Feminino , Predisposição Genética para Doença , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/genética , Hepatite C/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores Sexuais
3.
Comput Biol Chem ; 75: 39-44, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29738913

RESUMO

Multiple sequence alignment (MSA) is one of the most important tasks in bioinformatics and it can be used to prediction of structures or functions of unknown proteins and to phylogenetic tree reconstruction. There are many heuristics to perform multiple sequence alignment, as Progressive Alignment, Ant Colony, Genetic Algorithms, among others. Along the years, some tools were proposed to perform MSA and MSA-GA is one of them. The MSA-GA is a tool based on Genetic Algorithm to perform multiple sequence alignment and its results are generally better than other well-known tools in bioinformatics, as Clustal W. The COFFEE objective function was implemented in the MSA-GA in order to allow it to produce better alignments to less similar sequence sets of proteins. Nonetheless, the COFFEE objective function is not suited do perform multiple sequence alignment of nucleotides. Thus, we have modified the COFFEE objective function, previously implemented in the MSA-GA, to allow it to obtain better results also to sequences of nucleotides. Our results have shown that our approach has achieved better results in all cases when compared with standard COFFEE and most of cases when compared with WSP for all test cases from BAliBase and BRAliBase. Moreover, our results are more reliable because their standard deviations have less variation.


Assuntos
Algoritmos , DNA/genética , Proteínas/genética , Alinhamento de Sequência
4.
Arq. bras. neurocir ; 24(4): 133-143, dez. 2005. tab
Artigo em Português | LILACS | ID: lil-462359

RESUMO

Este projeto é trabalho do Departamento de Trauma da Sociedade Brasileira de neurocirurgia, realizado com a colaboração de diversas instituições, com o objetivo de conceber uma infra-estrutura que permita dados via internet entre instituições. Descrevemos a situação atual do "Projeto Diretrizes de Atendimento ao Traumatismo Craniencefálico". Apresentamos os resultados iniciais de um estudo cooperativo entre diversas instituições médicas através da criação de um banco de dados e estabelecemos um novo protocolo de estudo. Propomos que o sistema atuial evolua à semelhança do BrainITGroup. No momento é ima proposta conceitual, de uma estrutura de coordenação entre serviços e de acesso a bancos de dados e que estabeleça critérios para publicação.


Assuntos
Humanos , Traumatismos Craniocerebrais , Estudos Multicêntricos como Assunto
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