OBJECTIVE: Recent studies have shown that circulating microRNAs might be useful, novel biomarkers for the diagnosis of acute myocardial infarction. The aims of this study were to evaluate the expression of cardiac-specific miRNAs (miR-1, -133a, -208b, and -499) in patients with acute myocardial infarction and to compare the diagnostic values of these miRNAs with that of cardiac troponin T. METHODS: Sixty-seven plasma samples obtained from patients with acute myocardial infarction and 32 plasma specimens collected from healthy volunteers were analyzed in this study. The levels of cardiac-specific miRNAs (miR-1, -133a, -208b, and -499) were measured by quantitative reverse transcription-polymerase chain reaction, and the concentrations of plasma cardiac troponin T were measured using electrochemiluminescence-based methods and an Elecsys 2010 Immunoassay Analyzer. RESULTS: The levels of plasma miR-1, -133a, -208b, and -499 were significantly higher in acute myocardial infarction patients (all p<0.001) than in healthy volunteers. The expression of the cardiac-specific miRNAs in acute myocardial infarction patients decreased to close to the baseline levels at the time of hospital discharge (all p>0.05). There were no correlations between the levels of the four circulating miRNAs and the clinical characteristics of the study population (all p>0.05). Furthermore, receiver operating characteristic curve analyses showed that the four plasma miRNAs were not superior to cardiac troponin T for the diagnosis of acute myocardial infarction (all p>0.05). CONCLUSION: Our results demonstrate that circulating miR-1, -133a, -208b, and -499 may be useful biomarkers in acute myocardial infarction patients but that these miRNAs are not superior to cardiac troponin T for the diagnosis of acute myocardial infarction.

Árvores utilizando os métodos de neighbor-joining, máxima parcimônia, evolução mínima, máxima verossimilhança e bayesiana, construídas baseadas em seqüências de rDNA 16S de 181 linhagens-tipo de espécies de Bacillus e taxa relacionados, mostraram a formação de nove grupos filogenéticos. A análise filogenética mostrou que Bacillus não é um grupo monofilético. B. subtilis se colocou no Grupo 1. Grupos 4, 6 e 8, respectivamente, consistiram de bacilos termofílicos, halofílicos ou halotolerantes e alcalifílicos. Grupos 2, 4 e 8 consistindo de espécies de Bacillus e gêneros relacionados demonstraram que o sistema taxonômico corrente não concorda perfeitamente com as árvores evolucionárias por rDNA 16S. A posição de Caryophanaceae e Planococcaceae no Grupo 2 sugere que estes podem ser transferidos para Bacillaceae, e a heterogeneidade do Grupo 2 implica em que algumas espécies de Bacillus neste grupo podem pertencer a vários novos gêneros. O Grupo 9 foi principalmente composto de gêneros de Bacillaceae (excluindo Bacillus), portanto algumas espécies de Bacillus no Grupo 9: B. salarius, B. qingdaonensis e B. thermcloacae podem não pertencer a Bacillus. Quatro espécies de Bacillus, B. schlegelii, B. tusciae, B. edaphicus e B. mucilaginosus foram claramente colocadas fora dos nove grupos.

Neigh-borjoining, maximum-parsimony, minimum-evolution, maximum-likelihood and Bayesian trees constructed based on 16S rDNA sequences of 181 type strains of Bacillus species and related taxa manifested nine phylogenetic groups. The phylogenetic analysis showed that Bacillus was not a monophyletic group. B. subtilis was in Group 1. Group 4, 6 and 8 respectively consisted of thermophiles, halophilic or halotolerant bacilli and alkaliphilic bacilli. Group 2, 4 and 8 consisting of Bacillus species and related genera demonstrated that the current taxonomic system did not agree well with the 16S rDNA evolutionary trees. The position of Caryophanaceae and Planococcaceae in Group 2 suggested that they might be transferred into Bacillaceae, and the heterogeneity of Group 2 implied that some Bacillus species in it might belong to several new genera. Group 9 was mainly comprised of the genera (excluding Bacillus) of Bacillaceae, so some Bacillus species in Group 9: B. salarius, B. qingdaonensis and B. thermcloacae might not belong to Bacillus. Four Bacillus species, B. schlegelii, B. tusciae, B. edaphicus and B. mucilaginosus were clearly placed outside the nine groups.