Awareness, consecuencias de una experiencia estresante: [revisión] / Anesthesia awareness: [review]

Anesthesia awareness, or "unintended intra-operative awareness" occurs during general anesthesia, on the operating table, when a patient has not had enough general anesthetic or analgesic to prevent consciousness or waking up during surgery. According to international studies its global incidence ranges from 0.1 to 0.2 percent. Its impact on people can be as severe as other traumatic experiences such as natural disasters, violent fights or sexual abuse. The prevalence of symptoms compatible with post traumatic stress disorder can be as high as 50 percent, after experiencing the awareness phenomenon. This paper reviews the main issues of the awareness phenomenon.

Identificación de asociaciones clínico-patológicas e hipermetilación de genes supresores de tumores en cáncer gástrico difuso a través de análisis de Hierarchical clustering / Hierarchical clustering analysis to detect associations between clinical and pathological features of gastric tumors and hypermethylation of suppressor genes

Background:Methylation is an inactivation mechanism for tumor suppressor genes, that can have important clinical implications. Aim: To analyze the methylation status of 11 tumor suppressor genes in pathological samples of diffuse gastric cancer. Material and methods: Eighty three patients with diffuse gastric cancer with information about survival and infection with Epstein Barr virus, were studied. DNA was extracted from pathological slides and the methylation status of genes p14, p15, p16, APC, p73, FHIT, E-caderin, SEMA3B, BRCA-1, MINT-2 y MGMT, was studied using sodium bisulphite modification and polymerase chain reaction. Results were grouped according to the methylation index or Hierarchical clustering (TIGR MultiExperiment Viewer). Results: Three genes had a high frequency of methylation (FHIT, BRCA1, APC), four had an intermediate frequency (p15, MGMT, p14, MINT2) and four had a low frequency (p16, p73, E-cadherin, SEMA3B). The methylation index had no association with clinical or pathological features of tumors or patients survival. Hierarchical clustering generated two clusters. One grouped clinical and pathological features with FHIT, BRCA1, and APC and the other grouped the other eight genes and Epstein Barr virus infection. Two significant associations were found, between APC and survival and p16/p14 and Epstein Barr virus infection. Conclusions: Hierarchical clustering is a tool that identifies associations between clinical and pathological features of tumors and methylation of tumor suppressor genes.