Factores pronósticos clinicopatológicos en el adenocarcinoma gástrico resecado con intención curativa / Clinicopathological prognostic factors in curatively resected gastric adenocarcinona

Introducción. Evaluamos la influencia de diferentes variables clínicas, patológicas y terapéuticas sobre la supervivencia tras gastrectomía con intención curativa en pacientes con adenocarcinoma gástrico. Pacientes y métodos. Entre 1985 y 1992, 202 pacientes fueron gastrectomizados por adenocarcinoma gástrico, 108 (53,4 por ciento) con intención curativa. Los datos clinicoterapéuticos fueron obtenidos retrospectivamente de las historias clínicas, y los patológicos de la revisión de sus preparaciones. El análisis estadístico utilizado fue el test de rangos logarítmicos (análisis univariante) y el modelo de regresión de Cox (análisis multivariante), siendo la variable dependiente el tiempo de supervivencia. Resultados. La tasa de supervivencia a los 5 años fue del 55 por ciento. Los datos de mal pronóstico en el análisis univariante fueron: afectación difusa del estómago o localización proximal, práctica de esplenectomía, transfusión perioperatoria, presencia de microinvasión capilar, grado de T y estadio tumoral avanzado, edad mayor de 65 años, afectación ganglionar y desarrollo de complicaciones postoperatorias. En el análisis multivariante, estas tres últimas variables emergen como factores pronósticos desfavorables independientes para la supervivencia. Conclusiones. Edad avanzada, afectación ganglionar y morbilidad postoperatoria son factores que influyen desfavorablemente en la supervivencia de pacientes con adenocarcinoma gástrico resecado con intención curativa (AU)

Nest building is a sexually selected behaviour in the barn swallow.

Females may use male nest building to assess male parental quality, and nest size would then be a sexually selected trait. In the barn swallow, Hirundo rustica, females select their partner by his tail length, a character believed to signal good genes. Both sexes participate in nest building, although male participation is negatively related to his attractiveness as reflected by tail length. We tested the hypothesis that nest building is a sexually selected trait: females paired with males of high parental quality (as shown by the male during nest building) may obtain a mate providing large amounts of parental investment, while, as has been shown previously, females mated to attractive (long-tailed) males will acquire mates with good genetic quality. Therefore, since nest building in barn swallows occurs after mating, we predicted a postmating sexual selection process by which the female invests differentially in reproduction depending on the male's nest-building effort (reflecting his willingness to invest in reproduction). The volume of material in a nest was related to the male's contribution to nest building and, in agreement with our hypothesis, in a multiple regression analysis, male tail length and nest material volume were negatively related to laying date and positively to female investment in reproduction (total number of eggs laid during the breeding season). Moreover, females paired with long-tailed males (which contribute very little to nest building), but using the same amount of nest material as females paired with short-tailed males, reduced the thickness of the nest and hence increased its capacity. Therefore, in the barn swallow two different traits appear to be sexually selected: tail length of males owing to the good genes process and nest-building ability owing to the good parent process. (c) 1998 The Association for the Study of Animal Behaviour.