Aging related ER stress is not responsible for anabolic resistance in mouse skeletal muscle.

Anabolic resistance reflects the inability of skeletal muscle to maintain protein mass by appropriate stimulation of protein synthesis. We hypothesized that endoplasmic reticulum (ER) stress contributes to anabolic resistance in skeletal muscle with aging. Muscles were isolated from adult (8 mo) and old (26 mo) mice and weighed.

Morphological variation of intervessel pit membranes and implications to xylem function in angiosperms.

Pit membranes between xylem vessels have been suggested to have functional adaptive traits because of their influence on hydraulic resistance and vulnerability to embolism in plants. Observations of intervessel pit membranes in 26 hardwood species using electron microscopy showed significant variation in their structure, with a more than 25-fold difference in thickness (70-1892 nm) and observed maximum pore diameter (10-225 nm). In some SEM images, pit membrane porosity was affected by sample preparation, although pores were resolvable in intact pit membranes of many species.