[Seroprevalence of Chagas disease at the Instituto Nacional de Cardiología Ignacio Chávez from 2004 to 2010].

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.

Molecular cloning and purification of an endochitinase from Serratia marcescens (Nima).

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.