Survival in Cystic Fibrosis: Trends, Clinical Factors, and Prediction Models.

Cystic fibrosis (CF) is an autosomal recessive genetic disease that results in multiple medical complications, and ultimately decreased survival of affected patients. Due to multiple advances in early diagnosis, nutrition, and aggressive treatment of complications, survival of these patients has improved dramatically in the past 40 years. However, despite improved care, patients still die at a relatively young age, most commonly due to respiratory failure. In order to extend survival, the sickest patients with CF are considered for lung transplant. An accurate understanding of a CF patient's expected survival and health trajectory is critical for appropriate patient selection and timing of transplantation. This review discusses how survival in CF has changed over the past four decades, the clinical factors that are associated with survival, as well as the use of models to predict survival and optimal timing of lung transplant in patients with CF.

Longitudinal study of the effects of a high-fat diet on glucose regulation, hippocampal function, and cerebral insulin sensitivity in C57BL/6 mice.

Although the increasing rate of obesity has stimulated interest in the effects of diet composition on peripheral systems, comparatively little work has been done to examine effects upon the brain. A diet high in fat is one of many factors that can promote obesity, and previous research has shown that such a diet can produce learning and memory impairment in rodents. In the present study, C57BL/6 mice were placed on either a high-fat (45% kcal fat) or regular (5% kcal fat) diet, and examined at different points during the subsequent year. The high-fat diet led to increased weight gain, significant impairment in glucoregulation, and altered insulin-mediated signaling within the hippocampus, an area of the brain believed to be important for the acquisition of memory. Following ten months on either diet, synaptic function in ex vivo hippocampal slices was examined, and neither stimulus-response curves nor electrically induced long-term potentiation were found to be different. As well, performance in the Morris water maze, a hippocampal-dependent test of spatial memory, was not influenced by diet. However, mice consuming a high-fat diet failed to perform an operant bar-pressing task, indicating a significant impairment to procedural learning and consolidation processes. Despite causing broad peripheral changes in C57BL/6 mice, consuming a large proportion of calories from saturated fat had only a limited effect upon learning and memory, which suggests that certain aspects of brain function are selectively vulnerable to the influences of diet.