Detección histológica y molecular de Helicobacter pylori y genotipificación con base en los genes de virulencia babA2 e iceA en pacientes con patología gástrica benigna / Molecular and histological detection of Helicobacter pylori and genotyping based on babA2 and iceA in patients with benign gastric pathologies

Objective: To investigate the presence of Helicobacter pylori in a Colombian population. Material and Methods: Gastric biopsies from 60 patients with benign gastric pathologies were submitted to histopathological examination and genotyped by PCR through amplification of babA2 and iceA genes. Results: The presence of H. pylori was demonstrated in 78.3 percent, 63.3 percent and 66.7 percent of the samples after Giemsa staining, andH. pylori 16S DNAr and iceA gene amplification, respectively. In addition, H. pylori babA2 positive was found infecting 7 patients. Among the iceA positive samples, 35 percent were identified as iceAl, 47.5 percent as iceA2 and 17.5 percent contained iceAl and iceA2 or different iceA2 types. This work allowed detection and genotyping of H. pylori, demonstrating a low proportion of patients carrying strains babA2 positive and an iceA genotype distribution according to previous reports. No association was found between the presence of babA2 and iceA genes and ulcer disease.

Objetivo: El presente estudio investiga la presencia de Helicobacter pylori en pacientes de una población colombiana con enfermedad gastro-duodenal benigna y realiza su genotipificación usando como blanco los genes babA2 e iceA. Pacientes y Métodos: Se analizaron biopsias gástricas de 60 pacientes usando histopatologíay RPC. Resultados: La presencia de H. pylori se demostró en 78,3 por ciento, 63,3 por ciento y 66,7 por ciento de los pacientes, mediante tinción de Giemsa, amplificación del gen 16S ADNr y del locus iceA, respectivamente. Helicobacter pylori babA2 positivo se encontró infectando 7 pacientes y de las 40 muestras positivas para la presencia del locus iceA, 35 por ciento eran iceAl, 47.5 por ciento iceA2 y en 17,5 por ciento se evidenció infección múltiple. Se aportan datos sobre la prevalencia de H. pylori encontrando una baja proporción de casos babA2 positivos y una distribución de los genotipos iceA acorde con datos reportados previamente. La presencia de los genes babA2 e iceA no se encontró asociada con la presentación de úlcera.

Biochemical comparison of venoms from young Colombian Crotalus durissus cumanensis and their parents

Crotalus durissus cumanensis, a rattlesnake endemic to Colombia and Venezuela, is considered one of the most lethal snake species in Latin America. The aim of the present study was to compare the protein content and biological activity of the venom obtained from eight specimens of C. durissus cumanensis, namely two adults from different localities of Colombia and six offspring born in captivity. Protein profiles of crude venoms were analyzed by SDS-PAGE and RP-HPLC, and biological activities were evaluated for lethality, edema, defibrination, hemolytic and coagulant activities to assess individual venoms of adults and a pool of young snake venoms. Transient edema appeared rapidly after venom inoculation, whereas hemorrhagic effect was not observed. Differences in protein profiles, lethality, hemolytic, coagulant and defibrinating activities between both adult snake venoms were observed; those from the mother snake exhibited higher activities. Venoms from young snakes were similar to the one obtained from the mother, but the coagulant effect was stronger in offspring venoms. Notably, biological effects of the father snake venom were not comparable to those previously described for C. durissus cumanensis from Venezuela and C. durissus terrificus from Brazil, confirming the high variability of the venom from Crotalus species.