Physicians' perceptions of risk adjustment and health policy formation in Minnesota.

A questionnaire was used to assess Minnesota physicians' knowledge of and opinions about risk adjustment, a policy designed to modify payments to health providers based on the relative "sickness" level of the provider's patient population. Additionally, attitudes toward this policy were measured to examine physicians' perceptions of health policy formation in Minnesota. Although familiarity with this policy appears low, respondents support the concept of diagnosis-based risk adjustment. Physicians are divided on whether to further modify risk-adjusted rates with a conversion factor; their written comments suggest a mistrust of the policymaking process. Physicians most often listed the Minnesota Medical Association as a primary source for health policy information, while few respondents reported any communication with state legislators in health policy matters. Respondents perceive an imbalance in the influence wielded by various entities in health policy formation. Only 5% believe individual physicians have significant influence in policymaking. Increased communication between physicians and their legislators may be one way for physicians to gain such influence.

Concentration-dependent stimulation and inhibition of growth cone behavior and neurite elongation by protein kinase inhibitors KT5926 and K-252a.

We examined the concentration- and time-dependent effects of two related protein kinase inhibitors, KT5926 and K-252a, on neurite formation and nerve growth cone migration of chick embryo sensory neurons. The effects of these drugs on neurite formation over an 18-h period were dissimilar. KT5926 stimulated neurite formation at concentrations between 100 and 500 nM and inhibited neurite formation at 5 microM. K-252a had no stimulatory effects on neurite formation, and it inhibited neurite formation at concentrations above 50 nM. This difference may occur because K-252a inhibits activation of the nerve growth factor receptor trk A, while KT5926 does not inhibit trk A. Both drugs, however, had similar immediate effects on growth cone migration. Growth cone migration and lamellipodial spreading were rapidly stimulated by 500 nM concentrations of KT5926 and K-252a. At 2 microM levels of either drug, growth cone spreading was still stimulated, but growth cone migration was inhibited by both drugs. These results show that changes in protein phosphorylation/dephosphorylation can rapidly regulate the cellular machinery that is responsible for driving growth cone migration and neurite elongation. The different effects of 2 microM concentrations of either KT5926 or K-252a on growth cone spreading versus migration suggests that the actin-dependent protrusive motility of the growth cone leading margin is regulated differently by changes in protein phosphorylation and dephosphorylation than the cytoskeletal mechanism that drives neurite elongation.