OBJECTIVE High variability in delivering the target torque is reported for friction-style mechanical torque limiting devices (F-S MTLDs). The effect of aging (number of use) on the accuracy of these devices is not clear. The purpose of this study was to assess the effect of aging on the accuracy (±10% of the target torque) of F-S MTLDs. MATERIALS AND METHODS Fifteen new F-S MTLDs and their ap...

AIM To observe the effect of cholecystokinin (CCK) on lipofusin value, neuronal dendrite and spine ultrastructure, and total cellular protein during the process of experimental neuronal aging. METHODS Experimental neuronal aging study model was established by NBA2 cellular serum-free culture method. By using single intracellular lipofusin value from microspectrophotometry, morphology of neuro...

Programmed aging refers to the idea that organisms including humans possess biological mechanisms or programs that purposely limit their internally determined lifespans in order to obtain an evolutionary advantage. To most science-oriented people programmed aging appears to be scientifically ridiculous because it directly conflicts with Darwin’s survival-of-the-fittest concept. Some have compar...

OBJECTIVE Age is the strongest risk factor for venous thrombosis. Vessel wall changes such as thickening of venous valves may be one of the contributing mechanisms. We determined thickness and function of venous valves in the popliteal vein with ultrasound in 77 healthy individuals. METHODS AND RESULTS The study included 6 age groups ranging from 20 to 80 years old. Thickness of the valves wa...

Irradiation of stored red blood cells (RBC) is increasingly utilized for patients who are immunosuppressed or on chemotherapeutic regimens. With the growing demand for irradiated cellular blood products, there has been an increasing need for transfusion services to store previously irradiated blood until needed for transfusion. The effect of irradiation on aging stored RBC has not been studied ...

Aging is becoming a critical heath care issue and a burgeoning economic burden on society. Mechanotransduction is the ability of the cell to sense, process, and respond to mechanical stimuli and is an important regulator of physiologic function that has been found to play a role in regulating gene expression, protein synthesis, cell differentiation, tissue growth, and most recently, the pathoph...

OBJECTIVE To determine the effect of aging on choroidal blood flow (ChBFlow) in the foveolar region of the normal ocular fundus. METHOD Choroidal blood flow was determined using laser Doppler flowmetry. Twenty-nine eyes of 29 normal subjects whose ages ranged from 15 to 76 years (mean+/-SD, 42+/-18 years) were included in this study. Relative choroidal blood velocity (ChBVel), choroidal blood...

UNLABELLED Myocardial perfusion reserve (hyperemic divided by basal myocardial blood flow) describes vasodilator responsiveness of coronary-resistive vessels. The effect of aging and gender on myocardial perfusion reserve remains controversial. METHODS We studied 56 normal volunteers (21 women, 35 men; aged 50 +/- 20 yr, range 21-86 yr) with 15O-water PET to measure myocardial blood flow duri...

Two NO synthase (NOS) isoforms have been described in vessels, an endothelial constitutive NOS (eNOS) and an inducible NOS (iNOS). The purpose of the present study was to examine the endothelium-dependent and endothelium-independent hypotensive response in aging rats, analyzing the ability of their vessels to produce NO. The studies were performed in 2 groups of euvolemic, conscious, male Wista...

Article history: Received 3 October 2012 Received in revised form 10 January 2013 Accepted 12 February 2013 Available online 15 March 2013 Although lifespan changes in cognitive performance and Flynn effects have both been well documented, there has been little scientific focus to date on the net effect of these forces on cognition at the population level. Two major questions moving beyond this...