Evaluation of the Role of Microvascular Pathology on Peripheral Artery Disease

Background: Peripheral Artery Disease (PAD) begins with atherosclerotic narrowing of arteries, including those that supply the legs. Individuals with PAD experience pain during walking, which becomes increasingly limiting. Studies from our group and others have shown that a myopathy is present in the skeletal muscle of PAD patients, and is characterized by myofiber degeneration, fibrosis, and remodeling of vessels ranging from 50 – 150 mm in diameter. However, microvascular pathology, particularly of the smallest microvessels (5 – 15 mm in diameter) remains poorly characterized. Furthermore, little is known about the relationships between microvascular architecture, microperfusion, and patient walking performance. We hypothesize that microvascular pathology is present in the terminal microvasculature of PAD muscle compared to control and worsens with PAD severity. Additionally, we hypothesize that microvascular architecture is associated with deficits in micro- and macro- perfusion and walking performance in PAD patients with intermittent claudication (IC). Methods: Gastrocnemius biopsy specimens were collected from control, PAD patients with IC, and PAD patients with critical limb ischemia. Microvascular architecture, microvascular fibrosis, total collagen, and the abundance and phenotype of pericytes were quantified. Microvascular perfusion was assessed by Contrast Enhanced Ultrasonography (CEU). Gardner walking protocols were used to assess claudication onset time (COT) and peak walking time (PWT). Patients also completed the Walking Impairment Questionnaire (WIQ). Results: Microvascular pathology increased with advancing PAD severity and included progressive increases in basement membrane thickening, abundance of aSMA+ pericytes, and microvessel density. In advanced PAD muscle, increases were observed in total fibrotic burden and peri-microvascular Collagen I and IV deposition. aSMA+ pericytes expressed TGF-b1. Relationships were observed between microvascular architecture and microperfusion both at rest and after ischemic stress. Microvascular architecture was associated with macrovascular hemodynamic restrictions. Microvascular architecture was associated with COT, PWT, and patient self-reports of walking speed, walking distance, and stair climbing ability. Conclusions: Microvascular pathology worsens with PAD severity in association with fibrosis. Alteration of microvascular architecture contributes to microperfusion deficits and walking limitations in PAD

Rold Ambiguity among Foster Parents: Semi-Professionals in Professionalizing Organizations

Because foster parent role ambiguity has been viewed primarily as a micro-level phenomenon, efforts to reduce its negative consequences have emphasized ameliorist solutions which attempt to alter the behavior of individuals. We suggest that consideration of role ambiguity as a macro-level phenomenon provides a sounder basis for developing long-range solutions which can alter the structure of foster care organizations in ways which will complement existing ameliorist strategies. As semi-professionals, the work-role expectations of foster parents are seen as being contradictory to the goals of a profess ionalizing organizational structure. The transitional nature of this professionalizing process, and the contradictions which it generates, are discussed. Some consequences are evidenced by empirical data obtained from a state-wide study of a public foster care organization

Dyslipidemia and Food Security in Low-Income US Adolescents: National Health and Nutrition Examination Survey, 2003-2010.

INTRODUCTION: Low levels of food security are associated with dyslipidemia and chronic disease in adults, particularly in women. There is a gap in knowledge about the relationship between food security among youth and dyslipidemia and chronic disease. We investigated the relationship between food security status and dyslipidemia among low-income adolescents. METHODS: We analyzed data from adolescents aged 12 to 18 years (N = 1,072) from households with incomes at or below 200% of the federal poverty level from the National Health and Nutrition Examination Survey (NHANES) 2003-2010. We used logistic regression to examine the relationship between household food security status and the odds of having abnormalities with fasting total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), serum triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), TG/HDL-C ratio, and apolipoprotein B (Apo B). Models included age, sex, race/ethnicity, smoking status, partnered status in the household, and maternal education, with additional adjustment for adiposity. RESULTS: Household food security status was not associated with elevated TC or LDL-C. Adolescents with marginal food security were more likely than food-secure peers to have elevated TGs (odds ratio [OR] = 1.86; 95% confidence interval [CI], 1.14-3.05), TG/HDL-C ratio (OR = 1.74; 95% CI, 1.11-2.82), and Apo B (OR = 1.98; 95% CI, 1.17-3.36). Female adolescents with marginal food security had greater odds than male adolescents of having low HDL-C (OR = 2.69; 95% CI, 1.14-6.37). No elevated odds of dyslipidemia were found for adolescents with low or very low food security. Adjustment for adiposity did not attenuate estimates. CONCLUSION: In this nationally representative sample, low-income adolescents living in households with marginal food security had increased odds of having a pattern consistent with atherogenic dyslipidemia, which represents a cardiometabolic burden above their risk from adiposity alone