The Relation Between Managed Care Market Share and the Treatment of Elderly Fee-For-Service Patients with Myocardial Infarction

Managed care may affect medical treatments for non-managed-care patients if it alters local market structure or physician behavior. We investigate whether higher levels of overall managed care market share are associated with greater use of recommended therapies for fee-for-service patients with acute myocardial infarction using data on 112,900 fee-for-service Medicare beneficiaries residing in one of 320 metropolitan statistical areas, with age >= 65 years, and admitted with an acute myocardial infarction between February 1994 and July 1995 from the Cooperative Cardiovascular Project. After adjustment for patient characteristics, severity of illness, characteristics of the hospital of admission, specialty of treating physicians, and other area characteristics, patients treated in areas with high levels of managed care had greater relative use of beta-blockers during hospitalization and at discharge and aspirin during hospitalization and at discharge, consistent with more appropriate care. Patients in high HMO areas may be less likely to receive angiography when compared to areas with low levels of managed care, although this result was only marginally significant. In unadjusted comparisons, patients in high HMO market share areas had lower 30 day mortality, but there were no differences in 30 day mortality when all of the control variables were included in the model. We conclude that managed care can have widespread effects on the treatment of patients and the quality of care they receive, even for patients not enrolled in managed care organizations.

Development of New Research-Quality Low-Resource Magnetometers for Small Satellites

Researchers from the University of Michigan (UM) and NASA Goddard Spaceflight Center (GSFC) are partnering to develop new types of magnetometers for use on future small satellites. These new instruments not only fulfill stringent requirements for low-amplitude and high-precision measurements, they are also enabling the team to develop a new approach to achieve high-quality magnetic measurements from space, without the need for a boom. Typically, space-based magnetometers are deployed on a boom that extends from the space vehicle to reduce exposure of magnetic noise emanating from the spacecraft, which could potentially contaminate measurements. The UMNASA team has developed algorithms to identify and eliminate spacecraft magnetic noise, which will allow placement of these economical, science-grade instrument magnetometers on and inside the satellite bus, instead of on a boom

Structure Preservation and Mohawk Inchoative Verbs

Proceedings of the Eighteenth Annual Meeting of the Berkeley Linguistics Society: General Session and Parasession on The Place of Morphology in a Grammar (1992), pp. 261-27

An electrostatic mechanism for Ca(2+)-mediated regulation of gap junction channels.

Gap junction channels mediate intercellular signalling that is crucial in tissue development, homeostasis and pathologic states such as cardiac arrhythmias, cancer and trauma. To explore the mechanism by which Ca(2+) blocks intercellular communication during tissue injury, we determined the X-ray crystal structures of the human Cx26 gap junction channel with and without bound Ca(2+). The two structures were nearly identical, ruling out both a large-scale structural change and a local steric constriction of the pore. Ca(2+) coordination sites reside at the interfaces between adjacent subunits, near the entrance to the extracellular gap, where local, side chain conformational rearrangements enable Ca(2+)chelation. Computational analysis revealed that Ca(2+)-binding generates a positive electrostatic barrier that substantially inhibits permeation of cations such as K(+) into the pore. Our results provide structural evidence for a unique mechanism of channel regulation: ionic conduction block via an electrostatic barrier rather than steric occlusion of the channel pore