Genotipificación de los factores de virulencia vacA y cagA de Helicobacter pylori en individuos de dos regiones de Colombia con riesgo opuesto de cáncer gástrico

Introduction: The overall prevalence of Helicobacter pylori infection is high in Colombia; however, in the country´s Andean region, gastric cancer rates far surpass those in coastal areas. Helicobacter pylori genotypes cagA positive and vacA s1 and m1 are associated with an increased risk of gastric cancer.Objective: To compare the distribution of H. pylori genotypes associated with virulence in two regions in Colombia with opposing risk for gastric cancer.Materials and methods: Four hundred and one gastric antral biopsies were obtained and analyzed from 401 individuals diagnosed with non-atrophic gastritis, atrophic gastritis and intestinal metaplasia: 256 came from the high-risk area cities of Tunja and Bogotá, and 145 from the low-risk area cities of Barranquilla, Santa Marta and Cartagena. Genotyping of virulence genes vacA and cagA was performed by PCR.Results: No difference was observed in the frequency of H. pylori infection between the two areas (77.3% vs 77.9 %, p=non significant, ns). The presence of cagA was higher in the low-risk area (77.9% vs. 69.2 %, p=ns). The vacA s1allele was also more prevalent in the low-risk area (61.8 % vs 72.0 %, p=ns). The vacA m1 allele was more prevalent in the high-risk area (57.2 % vs 42.8 %, p=ns). The cagA positive s1m1 combination was also more frequent in the low-risk area (48.9% vs 38.9%, p=ns).Conclusions: The differences in the risk of gastric cancer in these two geographic areas cannot be explained by differences in the prevalence of infection by H. pylori or by differences in the virulence of circulating strains.Introducción. La prevalencia de infección por Helicobacter pylori es alta en Colombia; en la zona andina las tasas de cáncer gástrico son altas mientras que en las zonas costeras son bajas. Los genotipos de H. pylori cagA positivo y vacA s1 y m1 se asocian con un mayor riesgo de cáncer gástrico.Objetivo. Determinar las diferencias en las frecuencias de los genotipos de H. pylori asociados a virulencia en dos regiones de Colombia con riesgo opuesto de cáncer gástrico.Materiales y métodos. Se analizaron 401 biopsias del antro gástrico provenientes de 401 individuos con diagnóstico de gastritis no atrófica, gastritis atrófica o metaplasia intestinal; 256 se obtuvieron en la zona de alto riesgo (Tunja y Bogotá) y, 145, en la zona de bajo riesgo (Barranquilla, Santa Marta y Cartagena). La genotipificación de los genes de virulencia cagA y vacA se hizo mediante reacción en cadena de la polimerasa (PCR).Resultados. No se observó diferencia en la frecuencia de infección por H. pylori entre las dos zonas (77,3 Vs. 77,9 %, p=no significativo, ns). La presencia de cagA fue mayor en la zona de bajo riesgo (77,9 Vs. 69,2 %, p=ns). El alelo vacA s1 también fue más prevalente en la zona de bajo riesgo (61,8 Vs. 72,0 %, p=ns). El alelo vacA m1 presentó mayor prevalencia en la zona de alto riesgo (57,2 Vs. 42,8 %, p=ns). La combinación cagA positivo s1m1 también fue más frecuente en la zona de bajo riesgo (48,9 Vs. 38,9 %, p=ns).Conclusiones. Las diferencias en el riesgo de cáncer gástrico en estas dos zonas no pueden explicarse por las diferencias en la prevalencia de infección por H. pylori o en la virulencia de las cepas circulantes

Relationship Between Self-Perceived Health, Vitality, and Posttraumatic Growth in Liver Transplant Recipients

Our objective was to analyze the differences in posttraumatic growth in 240 liver transplant recipients based on two factors. First, self-perceived health: better (Group 1 = G1) and worse (Group 2 = G2). Second, vitality: more (Group 3 = G3) and less (Group 4 = G4). The Posttraumatic Growth Inventory, SF-36 Health Survey (Item 2) and SF-12 Health Survey (vitality dimension) were used. Firstly, analyzing main effects recipients with better (G1) compared to worse (G2) self-perceived health, showed greater posttraumatic growth. Interaction effects were found on essential posttraumatic growth domains such as new possibilities (p = 0.040), personal strength (p = 0.027), and appreciation of life (p = 0.014). Statistically significant differences showed that among transplant recipients with worse self-perceived health (G2), those with more vitality had higher levels on abovementioned posttraumatic growth dimensions. However, in transplant recipients with better self-perceived health (G1) respective dimensions were not significantly influenced by the level of vitality. Among the recipients with less vitality (G4), those with better self-perceived health showed higher scores on abovementioned posttraumatic growth dimensions. We conclude that positive self-perceived health might compensate for a lack of vitality as well as a high level of vitality may compensate for negative self-perceived health regarding the development of crucial aspects of posttraumatic growth after liver transplantation.Ministerio de Economía y Competitividad de España PSI2014-51950-

Frecuencia de los genotipos babA2, oipA y cagE de Helicobacter pylori en pacientes colombianos con enfermedades gastroduodenales.

Introduction. Helicobacter pylori infection is associated with the development of several gastroduodenal diseases. Bacterial virulence genes have been found associated with an increased risk for gastric disease.Objectives. Herein, associations were made between the presence of vacA, cagA, cagE, babA2 and oipA genes in H. pylori isolates and the range of clinical consequences of the infection.Methods. PCR was used to amplify vacA, cagA, cagE, babA2 and oipA genes in 166 isolates-50 patients with peptic ulcer, 39 with non-atrophic gastritis, 26 with atrophic gastritis, 26 with intestinal metaplasia and 25 with gastric adenocarcinoma.Results. cagA, cagE, babA2 and oipA genes were found in 73%, 75%, 48% and 74% of isolates, respectively. The cytotoxic vacA s1m1/cagA positive/cage positive genotype was present in 64% (100/157) of isolates. A higher frequency of cytotoxic strains was observed in cancer patients (84%), intestinal metaplasia (91%) and peptic ulcer (81%) in comparison with gastritis patients (50%) (p=0.002, 0.008, 0.007, respectively). The oipA and babA2 frequency was higher in cytotoxic isolates than in non-cytotoxic isolates (oipA: 81% vs. 52%, P=0,003; babA2: 58% vs. 12% (pIntroducción. La infección con Helicobacter pylori está asociada con el desarrollo de diferentes enfermedades gastroduodenales. Varios genes de virulencia de H. pylori se han relacionado con mayor riesgo de enfermedad gástrica. Objetivos. El propósito de este trabajo fue determinar las posibles asociaciones entre la presencia de los genes vacA, cagA, cagE, babA2 y oipA en aislamientos de H. pylori de pacientes colombianos y las diferentes consecuencias clínicas de la infección. Materiales y métodos. Mediante PCR se evaluaron los genotipos cagA, vacA, cagE, oipA y babA2 en 166 aislamientos de H. pylori provenientes de 50 pacientes con úlcera péptica, 39 con gastritis crónica no atrófica, 26 con gastritis crónica atrófica, 26 con metaplasia intestinal y 25 con adenocarcinoma gástrico. Resultados. La frecuencia de los genotipos cagA, cagE, babA2 y oipA fue de 73%, 75%, 48% y 74%, respectivamente. El 64% (100/157) de los aislamientos presentó el genotipo citotóxico vacAs1m1/cagA positivo/cagE positivo. Se observó una mayor frecuencia de cepas citotóxicas en pacientes con cáncer (84%), metaplasia (91%) y úlcera (81%) en comparación con pacientes con gastritis no atrófica (50%) (p=0,002, 0,008 y 0,007, respectivamente). La frecuencia de oipA y babA2 fue mayor en cepas citotóxicas que en cepas no citotóxicas (oipA: 81% vs. 52%, p=0,003; babA2: 58% vs. 12%, p=0,000). No se observaron diferencias significativas en la frecuencia de los genes oipA o babA2 solos o en asociación con vacA y cagA/cagE y las diferentes enfermedades gastroduodenales. Conclusiones. No se encontraron evidencias que sugieran que los genes babA2 u oipA puedan servir como marcadores de ulcerogénesis o carcinogénesis en esta población, solos o en asociación con cagA, cagE o vacA

Cag pathogenicity island of Helicobacter pylori and its association to preneoplastic lesions and gastric cancer

Gastric cancer is one of the main causes of death by cancer in the world and the infection with Helicobacter pylori is one of the main risk factors associated with its appearance. Helicobacter pylori is a bacterium that colonizes the gastric mucosa, infecting about half of the world´s population. The pathological effects caused by infections with H. pylori greatly depend on an IV type secretion system encoded in the cag pathogenicity island (cagPAI). In this review, we describe the composition of the cagPAI, the alterations of cellular signaling pathways mediated by cagPAI which regulate oncogenic cellular responses that may increase the risk of malignant transformation associated with the infection and the importance of polymorphisms in cagPAI genes as potential markers of progression to gastric cancer

Presencia del virus de Epstein-Barr en casos colombianos de linfoma de Hodgkin y su relación con la respuesta al tratamiento.

The role of Epstein-Barr virus as etiologic agent in Hodgkin lymphoma (HL) development has been supported by the detection of viral DNA in the Reed-Sternberg cell in a subset of HL, and the high levels of latent membrane protein 1 expression in these tumors. To gain further evidence of this relationship, lymph nodes from 67 patients with HL were analyzed for the presence of Epstein-Barr virus using EBERs in situ hybridization and LMP-1 immunohistochemistry. Virus presence was related to histological subtype, patients' treatment response and tumor infiltrating lymphocytes phenotype. EBERs transcripts were found in 67% of the cases and LMP-1 in the Reed-Sternberg tumor cells at a 56.7% rate. The prevalence, as determined by histological subtype, was 69.81% for nodular sclerosing, 85.71% for mixed cellularity and 40% for lymphocyte-rich. Epstein-Barr virus presence was more frequent in children (84.2%) in comparison with adults (60.4%). Positive patients presented higher failure-free survival rates than Epstein-Barr virus negative patients. CD4 positive infiltrating T cells were present in a higher proportion in relation to CD8 positive T infiltrating cells, the mean percentages for both subsets were higher in Epstein-Barr virus positive cases. A high percentage of Epstein-Barr virus was present in HL with a probable association with treatment response. This suggests an application of Epstein-Barr virus detection to use as a prognosis marker in treatment response for HL cases.En el desarrollo y patogénesis del linfoma de Hodgkin se ha propuesto al virus de Epstein-Barr como posible factor etiológico debido a la detección de ADN viral en las células de Reed- Sternberg en un subgrupo de tumores y a los altos niveles de expresión de la proteína latente de membrana 1 (LMP-1). El objetivo de este estudio fue determinar la presencia de virus de Epstein-Barr en 67 ganglios linfáticos de pacientes con diagnóstico confirmado de linfoma de Hodgkin mediante hibridación in situ para la detección de transcritos de ARN del virus de Epstein-Barr e inmunohistoquímica para la detección de la proteína oncogénica LMP-1. La presencia del virus se relacionó con el subtipo histológico, la respuesta al tratamiento de los pacientes y el fenotipo del infiltrado linfocitario. En el 67% de los casos se detectaron transcritos de virus de Epstein-Barr, la proteína LMP-1 se detectó en 56,7% de los casos en la célula tumoral de Reed-Sternberg. La presencia del virus en cada tipo histológico fue de 69,81% en esclerosis nodular, 85,71% en celularidad mixta y 40% en clásico. El virus de Epstein-Barr se detectó con mayor frecuencia en niños (84,2%) en comparación con los adultos (60,4%) y los pacientes positivos para el virus mostraron mejor respuesta al tratamiento, reflejada en una menor tendencia a presentar recaídas. El análisis del infiltrado mostró un predominio de linfocitos T CD4 y presencia de linfocitos T CD8, con mayor expresión de ambas subpoblaciones en casos positivos para virus de Epstein-Barr. Los resultados muestran un alto porcentaje de infección por virus de Epstein-Barr con una probable implicación significativa en la respuesta al tratamiento, lo que sugiere que la detección de virus de Epstein-Barr se podría usar como marcador de pronóstico en este tipo de linfoma

Variación en el número de repeticiones EPIYA-C en la proteína CagA de aislamientos colombianos de Helicobacter pylori y su capacidad para inducir fenotipo colibrí en células epiteliales gástricas

Introduction. Studies using Western Helicobacter pylori strains have shown that a risk factor for gastric cancer is the number of EPIYA-C motifs in the cytotoxin-associated A protein. CagA is delivered into epithelial cells, where it becomes tyrosine phosphorylated in their EPIYA repeats and induces cytoskeleton rearrangements.Objectives. The objective of this study was to evaluate H. pylori cagA positive strains isolated from Colombian patients with gastroduodenal diseases for the number of EPIYA-C repeats in cagA and their ability to induce cytoskeleton rearrangements in epithelial cells.Materials and methods. We analyzed the 3' EPIYA repeats region of cagA by PCR in 93 H. pylori cagA positive strains from 49 patients with gastritis, 17 with gastric cancer, and 24 with duodenal ulcer. AGS cells exposed to the various H. pylori isolates were evaluated for rearrangements in their cytoskeleton.Results. Strains with one EPIYA-C were the most frequent in gastritis and duodenal ulcer patients. Strains with three EPIYA-C were mainly found in gastric cancer. We found a significantly higher risk of gastric cancer for individuals infected with strains harboring three EPIYA-C motifs (OR=12.4, CI95%: 2.32-66.3). Strains from gastric cancer showed significantly higher percentages of induction of cytoskeleton rearrangements in comparison with those from gastritis (p Mann-Whitney<0.005).Conclusions. H. pylori strains with three EPIYA-C repeats can confer an increased risk of cancer to infected individuals.Introducción. En los aislamientos de Helicobacter pylori del hemisferio occidental, se ha observado que el número de repeticiones EPIYA-C en la proteína CagA es un factor de riesgo para cáncer gástrico. La proteína CagA es introducida en la célula epitelial y, posteriormente, es fosforilada en las tirosinas presentes en los motivos EPIYA e induce rearreglos en el citoesqueleto.Objetivos. Nuestro propósito fue evaluar el número de repeticiones EPIYA-C y la habilidad para inducir rearreglos en el citoesqueleto en los aislamientos de H. pylori positivos para cagA, provenientes de pacientes colombianos con enfermedad gastroduodenal.Materiales y métodos. Mediante PCR, se analizó la región 3´ que contiene las repeticiones EPIYA-C, en 93 aislamientos de H. pylori positivos para cagA provenientes de 49 pacientes con gastritis, 17 con cáncer gástrico y 24 con úlcera duodenal. Los rearreglos del citoesqueleto se evaluaron mediante cultivos simultáneos de células AGS con las cepas de H. pylori.Resultados. En gastritis y úlcera duodenal se observó la mayor frecuencia de aislamientos con EPIYA C; los aislamientos con tres repeticiones EPIYA-C se encontraron con mayor frecuencia en cáncer gástrico. Encontramos un riesgo de cáncer gástrico significativamente mayor para individuos infectados con cepas con tres repeticiones EPIYA-C (OR=12,4; IC95% 2,32-66,3). Los aislamientos provenientes de cáncer gástrico mostraron mayores porcentajes de inducción de rearreglos en el citoesqueleto que los observados con aislamientos provenientes de gastritis (prueba de Mann-Whitney menor de 0,005).Conclusiones. La infección con cepas de H. pylori con tres repeticiones EPIYA-C puede conferir un mayor riesgo de desarrollar cáncer gástrico

Coping strategies in liver transplant recipients and caregivers according to patient posttraumatic growth

The purpose of this study was to analyze the differences in coping strategies employed by liver transplant recipients and their family members according to patient posttraumatic growth. Two matched groups of 214 liver transplant recipients and 214 family members were selected. The Posttraumatic Growth Inventory and Brief COPE were used. The most relevant results were: (1) Interactive effects in active coping, support (instrumental and emotional) and acceptance strategies, which were all used more by patients with higher growth levels, while their family members showed no differences in use of these strategies by patient growth level. Furthermore, while a low level of patient growth did not mark differences between them and their caregivers, a high level did, patients employing more active coping and support (instrumental and emotional), (2) In both groups a high level of patient growth was associated with more use of positive reframing and denial than a low one, and (3) Self-blame was employed by patients more than by their caregivers. It was concluded that a high level of posttraumatic growth in liver transplant recipients is associated with more use of healthy coping strategies, basically active coping, instrumental support, and emotional support.Ministerio de Economía y Competitividad PSI2014-51950-