Keratinocyte Migration in a Three-Dimensional In Vitro Wound Healing Model Co-Cultured with Fibroblasts

BACKGROUND: Because three-dimensional (3D) models more closely mimic native tissues, one of the goals of 3D in vitro tissue models is to aid in the development and toxicity screening of new drug therapies. In this study, a 3D skin wound healing model comprising of a collagen type I construct with fibrin-filled defects was developed. METHODS: Optical imaging was used to measure keratinocyte migration in the presence of fibroblasts over 7 days onto the fibrin-filled defects. Additionally, cell viability and growth of fibroblasts and keratinocytes was measured using the alamarBlue® assay and changes in the mechanical stiffness of the 3D construct was monitored using compressive indentation testing. RESULTS: Keratinocyte migration rate was significantly increased in the presence of fibroblasts with the cells reaching the center of the defect as early as day 3 in the co-culture constructs compared to day 7 for the control keratinocyte monoculture constructs. Additionally, constructs with the greatest rate of keratinocyte migration had reduced cell growth. When fibroblasts were cultured alone in the wound healing construct, there was a 1.3 to 3.4-fold increase in cell growth and a 1.2 to 1.4-fold increase in cell growth for keratinocyte monocultures. However, co-culture constructs exhibited no significant growth over 7 days. Finally, mechanical testing showed that fibroblasts and keratinocytes had varying effects on matrix stiffness with fibroblasts degrading the constructs while keratinocytes increased the construct's stiffness. CONCLUSION: This 3D in vitro wound healing model is a step towards developing a mimetic construct that recapitulates the complex microenvironment of healing wounds and could aid in the early studies of novel therapeutics that promote migration and proliferation of epithelial cells.

Prophylactic Dual Catheter Technique to Prevent Side Branch Snowplowing Complications during Angioplasty and Stenting

OBJECTIVE: Angioplasty and Stenting of intracranial atherosclerotic lesions have a higher complication rate and a large proportion of this is attributable to side branch arterial occlusion from forceful displacement of the atheroma into the ostia or snowplowing effect. This can result in severe disabilities when it result in small infarcts involving eloquent areas in the posterior circulation or the motor tracts. MATERIALS AND METHODS: We present a series of 6 cases utilizing a new dual catheter technique for maintaining the patency of at-risk vessels during angioplasty and stenting. There are several methods previously described to help reduce the incidence of stroke but because they do not have a physical presence in the ostia to protect it, they are unable to guarantee the patency of the vessel. RESULTS: All 6 patients underwent angioplasty and stenting with the technique. The patients were assessed for complications with post-procedure magnetic resonance imaging and no complications were found. CONCLUSION: In this preliminary series, the dual catheter technique appears to safe and effective in preventing occlusion of the adjacent branch arteries. This technique may facilitate the use of the Wingspan stent in the treatment of intracranial atherosclerotic stenotic segments by reducing the risk of peri-procedural stroke.

exploratory analysis of dynamic change of metabolic syndrome in relation to the risk of developing cardiovascular disease in a Chinese cohort

Metabolic syndrome [MS] is the syndrome closely related to cardiovascular disease [CVD] risk factors. Few prospective studies have compared the impact of dynamic changes of MS on the development of cardiovascular diseases [CVD]. Overall, 3461 subjects were recruited from a cohort study on Prevention of Multiple Metabolic disorders and MS in Jiangsu of China [PMMJS] with a follow up of 3.8 years. The associations between the dynamic changes [Difference, the value at first follow-up subtract the value at baseline] of MS, component numbers, components and relative risk [RR] of CVD were analyzed by using Cox regression model. The total incidence standardized rate of CVD was 2.58%,and the incidence standardized rates of CVD in MS-/follow-up MS-,baseline MS-/follow-up MS+, baseline MS+/follow-up MS- and baseline MS+/follow-up groups were 2.05%,5.01%,1.65% and 4.39% separately. After adjustment confounding factors Difference in FPG, BP and TG have significantly effects on the incidence of CVD. Difference of MS component numbers had the prediction ability of CVD, but MS groups based on baseline and first follow-up MS and/or non-MS had not. In Chinese, the dynamic change of MS component numbers was a useful predict factor for CVD

Effect of resveratrol on platelet aggregation in vivo and in vitro / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>Low or moderate consumption of red wine has a greater benefit than the consumption of other beverages in the prevention of atherosclerosis and coronary heart disease and this is increasingly attributed to the polyphenol compounds in red wine, such as resveratrol. In the present study, we investigated the effect of resveratrol on platelet aggregation in vitro and in vivo.</p><p><b>METHODS</b>Platelet aggregation in rabbits and normal subjects was measured using Born's method.</p><p><b>RESULTS</b>Resveratrol, at 10 - 1000 micromol/L, significantly inhibited platelet aggregation in vitro induced by collagen, thrombin, and ADP in healthy subjects. The inhibitory effect was concentration-dependent. Hypercholesterolemia induced by high-cholesterol diet enhanced ADP-induced platelet aggregation. Resveratrol 4 mg x kg(-1) x d(-1) inhibited ADP-induced platelet aggregation in vivo despite no changes in serum lipid levels.</p><p><b>CONCLUSIONS</b>Resveratrol inhibits platelet aggregation both in vitro and in vivo. This may be one of the mechanisms by which resveratrol prevents atherosclerosis.</p>

Stress and atherogenesis: smooth muscle cell mitogenic activity and other biochemical changes associated with sera of stressed subjects

The proliferation of smooth muscle cells in the arterial wall [VSMC] is considered to play a key role in the development of atherosclerosis. To investigate the possible contribution of "stress" [experimentally induced] to this process, blood from healthy volunteers, ages 21 to 65, screened to exclude major risk factors for coronary heart disease, was assayed for mitogenic activity after the subjects were exposed to one of 2 "stress" conditions. These consisted of a cognitive task with superimposed verbal harassment [group 1], and the cognitive task without harassment [group 2]. Mitogenic activity was determined by studying the growth stimulatory effects of PDGF-depleted plasma derived serum [PDS] from "stressed" subjects added to cultured VSMC, as measured by incorporation of radioactive thymidine into DNA or increase in cell number. In addition, changes in the steady state of the mRNA for the c-myc protooncogene were also assayed in VSMC by Northern blot analysis, using sera showing the greatest differential "pre/post stress" mitogenic activity. Blood pressure [BP], heart rate [HR], cortisol, and serum total and HDL cholesterol were also evaluated. All measurements were made immediately before [baseline] and after a 30 min interval. Analysis of the data revealed that there were 33% of subjects in group 1 with an increase of thymidine incorporation 15% or greater than baseline, versus 21% in group 2. The average increases were 45% and 30%. A higher percentage [35-42%] of subjects in group 1 responded with increases in systolic and diastolic blood pressure, compared to subjects in group 2 [15-20%]; the average in blood pressure was 10-15%. Similarly, more subjects [52%] in group 1 had an elevated [average 10-15%] serum cortisol, compared to the 42% in group 2 subjects. HR, total HDL cholesterol showed slight changes only. These results suggest that psychoactive factors may affect cardiovascular systems via rapid elicited rises in serum mitogenic activity for VSMC