The angiotensin-converting enzyme gene insertion/deletion polymorphism interacts with fear of falling in relation to stepping speed in community-dwelling older adults.

Background: Despite the association of genetic factors with falls, balance, and lower extremity functioning, interaction of the angiotensin-converting enzyme () gene insertion/deletion (I/D) polymorphism with fear of falling (FOF) in relation to stepping performance has, to the best of our knowledge, not been investigated in older adults.

Objective: The purpose of this study was to examine the interaction effects of the I/D polymorphism with FOF in relation to stepping performance in older adults.

Methods: Eighty-eight community-dwelling adults 60 years or older participated in a cross-sectional observational study.

Angiotensin-Converting Enzyme Insertion/Deletion Polymorphism, Lower Extremity Strength, and Physical Performance in Older Adults.

Background: Evidence for associations between the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene and physical performance is conflicting. Furthermore, investigations of relationships between lower extremity strength and physical performance have usually not considered the role of the ACE genotype, and it is unclear whether there are variations in relationships between lower extremity strength and physical performance among ACE genotypes in older adults.

Objective: The objectives of this study were to investigate associations between the ACE I/D polymorphism and physical performance and to determine whether relationships between lower extremity strength and physical performance vary among ACE genotypes in older adults.

Altered glial gene expression, density, and architecture in the visual cortex upon retinal degeneration.

Genes encoding the proteins of cytoskeletal intermediate filaments (IF) are tightly regulated, and they are important for establishing neural connections. However, it remains uncertain to what extent neurological disease alters IF gene expression or impacts cells that express IFs. In this study, we determined the onset of visual deficits in a mouse model of progressive retinal degeneration (Pde6b(-) mice; Pde6b(+) mice have normal vision) by observing murine responses to a visual task throughout development, from postnatal day (PND) 21 to adult (N=174 reliable observations).

Effects of age and retinal degeneration on the expression of proprotein convertases in the visual cortex.

Proprotein convertases (PCs) comprise a large family of subtilisin-like, eukaryotic, serine endoproteases that process substrates important in the development, homeostasis, and pathology of the nervous system. Despite important interactions with these substrates, including neurotrophins, PC expression throughout normal postnatal development and disease progression in the brain remains unknown. The primary objective of this study was to determine whether the expression profiles of widely expressed and tissue-specific PCs varied during normal brain development or neurological disorders.

Intracellular activation of human adamalysin 19/disintegrin and metalloproteinase 19 by furin occurs via one of the two consecutive recognition sites.

Adamalysin 19 (a disintegrin and metalloproteinase 19, ADAM19, or meltrin beta) is a plasma membrane metalloproteinase. Human ADAM19 zymogen contains two potential furin recognition sites (RX(K/R)R), (196)KRPR(200)R and (199)RRMK(203)R, between its pro- and catalytic domains. Protein N-terminal sequencing revealed that the cellular mature forms of hADAM19 started at (204)EDLNSMK, demonstrating that the preferred furin cleavage site was the (200)RMK(203)R downward arrow(204)EDLN.