RESUMO
Background: Different pathogens can cause dilated cardiomyopathy, one of them is Trypanosoma cruzi protozoan. T.cruzi-chronic infection causes chronic Chagasic cardiomyopathy and affects the sinus node and the conduction systembelow the bundle of His; besides, it shows excellent arrhythmogenic potential because of ventricular arrhythmias. Knowingthe clinical characteristics and performing serological tests to diagnose chronic Chagasic cardiomyopathy is essential. The serological diagnosis for searching the antibodies is based on the phase, which can be a predictor for the development of dilated cardiomyopathy. Objectives: In this work, the objective was to describe the frequency of dilated cardiomyopathy in patients with T. cruzi positive serology. Method: A total of 961 patients who were medically and clinically diagnosed with dilated cardiomyopathy were studied. Of these, 128 were diagnosed with chronic Chagasic cardiomyopathy and had positive serology for T. cruzi with two serological tests. Results: The clinical findings were obtained from the results of the electrocardiograms and were taken from the patient's clinical histories. Conclusion: In conclusion, complete blockage of the right branch of the bundle of His (44.2%) is one of the primary conduction disorders in the patients studied. Regarding seroprevalence, 14% of patients diagnosed with dilated cardiomyopathy had anti-T. cruzi antibodies.
Antecedentes: La cardiomiopatía dilatada puede ser causada por diferentes patógenos y uno de ellos es el protozoario Trypanosoma cruzi. La infección crónica causa la cardiomiopatía chagásica crónica, que afecta el nódulo sinusal y el sistema de conducción a nivel del haz de His; además, muestra gran potencial arritmogénico, ya que frecuentemente se presentan arritmias ventriculares. Para diagnosticar la cardiomiopatía chagásica crónica es indispensable conocer las características clínicas y realizar los ensayos serológicos. El diagnóstico serológico para la búsqueda de anticuerpos se basa en la fase de la enfermedad en la que se encuentre el individuo, los cuales pueden ser un predictor para el desarrollo de la cardiomiopatía dilatada. Objetivo: El objetivo de nuestro trabajo fue describir la frecuencia de cardiomiopatía dilatada en pacientes con serología positiva a T. cruzi en el Instituto Nacional de Cardiología Ignacio Chávez. Método: Se estudiaron 961 pacientes que fueron diagnosticados médica y clínicamente con cardiomiopatía dilatada y, de estos, 128 fueron diagnosticados con cardiomiopatía chagásica crónica, los cuales presentaban serología positiva a T. cruzi con dos pruebas serológicas. Resultados: Los hallazgos clínicos se obtuvieron de los resultados de los electrocardiogramas y fueron tomados de las historias clínicas de los pacientes. Conclusiones: En conclusión, el bloqueo completo de la rama derecha del haz de His (44.2%) es una de las principales alteraciones de la conducción en los pacientes estudiados. Con respecto a la seroprevalencia, el 14% de los pacientes con diagnóstico de cardiomiopatía dilatada tuvieron anticuerpos anti-T. cruzi.
Assuntos
Academias e Institutos , Cardiomiopatia Chagásica , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Cardiomiopatia Chagásica/epidemiologia , Cardiomiopatia Chagásica/diagnóstico , Estudos Soroepidemiológicos , México/epidemiologia , Adulto , Fatores de Tempo , Idoso , Doença de Chagas/epidemiologia , Doença de Chagas/diagnóstico , Cardiomiopatia Dilatada/epidemiologia , Trypanosoma cruzi/imunologia , Trypanosoma cruzi/isolamento & purificação , Adulto JovemRESUMO
An endochitinase gene from the Serratia marcescens Nima strain (chiA Nima) was cloned, sequenced, and expressed in Escherichia coli DH5alphaF', and the recombinant protein (ChiA Nima) was purified by hydrophobic interaction chromatography. chiA Nima contains an open reading frame (ORF) that encodes an endochitinase with a deduced molecular weight and an isoelectric point of 61 kDa and 6.84, respectively. A sequence at the 5'-end was identified as a signal peptide, recognized by Gram-negative bacteria transport mechanism. Comparison of ChiA Nima with other chitinases revealed a modular structure formed by the catalytic domain and a putative chitin-binding domain. The purified chitinase was able to hydrolyze both trimeric and tetrameric fluorogenic substrates, but not a chitobiose analog substrate. ChiA Nima showed high enzymatic activity within a broad pH range (pH 4.0-10.0), with a peak activity at pH 5.5. The optimal temperature for enzymatic activity was detected at 55 degrees C.