This continuing series gathers and presents original research results on the leading edge of medicine and biology. Each article has been carefully selected in an attempt to present substantial topical data across a broad spectrum. Topics discussed include the pathogenesis of paralysis in ALS patients; targeting testosterone pathways in prostate cancer treatment; the role of adrenocorticotropin beyond the glucocorticoid horizon; the etiology of facial paralysis; therapeutic measures for the prevention of postmenopausal symptoms; characterization of streptococcus pneumoniae by proteomic approaches; fetal magnetic resonance (MRI) images of normal developing brains; development of interstitial cells of cajal in the human digestive tract; and bacterial prophylaxis as an alternative to combat infections.