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The in vivo cardiac differentiation and functional effects of unmodified adult bone marrow mesenchymal stem cells (MSCs) after myocardial infarction (MI) is controversial. We postulated that ex vivo pretreatment of autologous MSCs using cardiomyogenic growth factors will lead to cardiomyogenic specification and will result in superior biological and functional effects on cardiac regeneration of chronically infarcted myocardium. We used a chronic dog MI model generated by ligation of the coronary artery (n = 30). Autologous dog bone marrow MSCs were isolated, culture expanded, and specified into a cardiac lineage by adding growth factors, including basic FGF, IGF-1, and bone morphogenetic protein-2. Dogs underwent cell injection >8 wk after the infarction and were randomized into two groups. Group A dogs (n = 20) received MSCs specified with growth factors (147 [+ or -] 96 x [10.sup.6]), and group B (n = 10) received unmodified MSCs (168 [+ or -] 24 x [10.sup.6]). After the growth factor treatment, MSCs stained positive for the early muscle and cardiac markers desmin, antimyocyte enhancer factor-2, and Nkx2-5. In group A dogs, prespecified MSCs colocalized with troponin I and cardiac myosin. At 12 wk, group A dogs showed a significantly larger increase in regional wall thickening of the infarcted territory (from 22 [+ or -] 8 to 32 [+ or -] 6% in group A; P < 0.05 vs. baseline and group B, and from 19 [+ or -] 7 to 21 [+ or -] 7% in group B, respectively) and a decrease in the wall motion score index (from 1.60 [+ or -] 0.05 to 1.35 [+ or -] 0.03 in group A; P < 0.05 vs. baseline and group B, and from 1.58 [+ or -] 0.07 vs. 1.56 [+ or -] 0.08 in group B, respectively). The biological ex vivo cardiomyogenic specification of adult MSCs before their transplantation is feasible and appears to improve their in vivo cardiac differentiation as well as the functional recovery in a dog model of the chronically infarcted myocardium. cardiac repair; myogenesis; chronic myocardial infarction; heart failure

The link between cell shape and microfilament network of vascular endothelial cells and endothelial cell expression of the endothelin-1 (ET-1) gene were studied in a setting free of external mechanical stimulus. It was observed that decreased cell-cell contact did not affect ET-1 peptide secretion and post-transcriptional mechanisms. Findings suggested that the shape and microfilament network of endothelial cells are potent posttranscriptional regulators of ET-1 gene expression.

Health care workers (HCW) within Veterans Health Administration (VHA) are at increased risk of sustaining bloodborne pathogen exposure (BBPE) and puncture injuries. We conducted a retrospective analysis of the Automated Safety Incident Surveillance and Tracking System (ASISTS) database and computed the standardized incident rate (SIR) across employees' characteristics, occupations, locations, and type of injuries. There were 23 277 puncture injuries and 10 385 BBPE incidents reported. Female HCW had higher incidence of BBPE (SIR = 43.28) and puncture injuries (SIR = 94.59). Physician Assistants had the highest SIR for puncture injuries (SIR = 145.78). Nurses had the highest reported BBPE (SIR = 77.83). Among frontline HCW, medical supply aide technicians reported the highest number of puncture injuries (SIR = 266.40). Inpatient settings were associated with higher risk for BBPE. Our findings indicate that both clinical care providers and frontline HCW are at elevated risk of sustaining these injuries; therefore, prevention and targeted intervention should focus on susceptible HCW's occupations, demographics, and job duties to reduce future injuries. [ABSTRACT FROM AUTHOR]