Translating science to medicine: The case for physician-scientists.

As the number of physician-scientists continues to decline, action must be taken to support them as they embark on their careers.

Global health inequity: scientific challenges remain but can be solved.

Advances in science and technology have transformed the health of the populations of the developed world, with substantial increases in life expectancy and reductions in morbidity. These advances have not, however, touched the lives of the poorest people of the world--the billions living in developing countries. This Review Series on global health highlights the key factors contributing to inequity in health across the globe and the scientific questions that remain unanswered but are critical to creating effective and appropriate health solutions. The gaps in knowledge identified in this series point the way for scientists to contribute to a changed world.

The discovery value of "Big Science".

The increasing complexity of biomedical research is leading to the exploration of new models for large-scale collaborative research. This Big Science approach, however, has created anxieties and potential tensions between investigator-driven research, and research guided by a more organized, collaborative effort. Another potential tension exists between research conducted purely in search of new knowledge and research aimed at finding solutions. We argue that big biomedicine--the work of coordinated multidisciplinary groups that use the latest technologies to solve complex problems--can be an important way to harness the creativity of individual investigators, stimulate innovation, and supply the infrastructure, experimental systems, and resources needed to solve the urgent health problems confronted by our global society. We discuss this using the example of the Global HIV Vaccine Enterprise.

Gastrin biosynthesis in canine G cells.

Gastrin requires extensive posttranslational processing for full biological activity. It is presumed that progastrin is cleaved at pairs of basic amino acids by a prohormone convertase to form a glycine-extended intermediate (G-Gly) that serves as a substrate for peptidyl-glycine alpha-amidating monooxygenase (PAM), resulting in COOH-terminally amidated gastrin. To confirm the nature of progastrin processing in a primary cell line, we performed [(35)S]methionine-labeled pulse-chase biosynthetic experiments in canine antral G cells. Radiolabeled progastrin reached a peak earlier than observed for G-Gly or amidated gastrin. G-Gly radioactivity accumulated in G cells and preceded the appearance of radioactivity in amidated gastrin. The conversion of G-Gly to amidated gastrin was enhanced by the PAM cofactor ascorbic acid. To determine whether one member of the prohormone convertase family (PC2) was responsible for progastrin cleavage, G cells were incubated with PC2 antisense oligonucleotide probes. Cells treated with antisense probes had reduced PC2 expression, an accumulation of radiolabeled progastrin, and a delay in the formation of amidated gastrin. Progastrin in antral G cells is cleaved via PC2 to form G-Gly that is converted to amidated gastrin via the actions of PAM.

Medicina interna / Textbook of internal medicine

Principios de la práctica médica: humanismo y ética; evaluación clínica; cardiología; gastroenterología; nefrología; reumatología, alergia y dermatología; oncología y hematología: se tratan los temas fisiología, fisiopatología, patología, diagnóstico, tratamiento. Enfermedades infecciosas. Endocrinologia, metabolismo y genética. Neurologia. Geriatria