5 kPa for the unloaded healthy wall (n = 25 specimens) and
plaque (n = 18), respectively. When the healthy wall was distended uniformly during AFM testing, two mechanically distinct populations emerged from comparisons of normal cumulative distributions, with median values of 9.8 and 76.7 kPa (n = 16). The higher values of stiffness may have been due to extended elastin, which was not present in the plaques. Rather, most plaques were identified via standard and immunofluorescent histology to be largely lipid laden, and they exhibited a nearly homogeneous linear elastic Selleckchem Sotrastaurin behavior over the small AFM indentations. Understanding the mechanics and mechanobiological factors involved in lesion development and remodeling could lead to better treatments for those lesions that are vulnerable to rupture. Copyright (C) 2011 S. Karger AG, Basel”
“Advances in stroke treatment have mirrored advances selleck kinase inhibitor in vascular imaging. Understanding and advances in reperfusion therapies
were made possible by improvements in computed tomographic angiography, magnetic resonance angiography, neurovascular ultrasound, and renewed interest in catheter angiography. As technology allows better noninvasive vascular diagnosis, digital subtraction angiography (the remaining gold standard for vascular imaging) is increasingly used for rescue procedures and elective interventions. This review will examine specific advantages and disadvantages of different vascular imaging modalities as related to stroke diagnosis.”
“Insulin was reported to decrease Na+/H+ exchange activity in murine vascular smooth muscle GDC-0449 order (VSM) tissue. In most other cells, insulin increases activity. We tested the effects of insulin on Na+/H+ exchange activity in primary cultured canine VSM cells. Intracellular pH (pH(i)) was measured with 2′,7′-bis(2-carboxyethyl)-5-carboxyfluorescein fluorescence and Na+ uptake by isotopic methods.
Insulin alone did not significantly affect pH(i) (7.13 +/- 0.05 vs. 7.10 +/- 0.03 for control and insulin, respectively; p = not significant), and EIPA alone lowered it to 6.98 +/- 0.04 (p < 0.05), upon which insulin lowered it further to 6.91 +/- 0.04 (p < 0.05). In the presence of a pH(i) clamp, pH(i)/extracellular pH (pH(o)) 7.1/7.4, insulin increased amiloride-sensitive Na-22 uptake by 98 +/- 25% (p < 0.05). At pH(i)/pH(o) 6.0/7.4 or 6.7/7.4, amiloride-sensitive Na-22 uptake was stimulated by 378 +/- 59 and 105 +/- 27%, respectively, compared to pH(i)/pH(o) 7.1/7.4 (p < 0.05 for all 3 versus each other), but was insulin insensitive. In acid-loaded cells (pH(i) 6.0), addition of extracellular Na+ (pH(o) 7.4) caused rapid intracellular alkalinization, and the initial rate was not affected by insulin. It is concluded that insulin stimulates acid accumulation in VSM cells that is normally effluxed by increased Na+/H+ exchange activity, and insulin may directly stimulate Na+/H+ exchange activity when cells are clamped at resting pH(i) but not at acidic pH(i).