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Biomedical subjects

L D Brown

Publications and source records attributed to L D Brown.

At least 91 records · Page 5Linked to original sources
PubMed1969

Some active derivatives of penicillin.

The antibacterial activities of a number of amide derivatives of penicillin against both penicillin-sensitive and penicillin-resistant cultures were determined. Several of them were found to possess significant inhibitory activity against certain gram-positive bacteria. The amides, although resistant to the destructive action of beta-lactamase, did not protect G in competitive experiments. One derivative, the O-benzylhydroxamide of penicillin G, was active against six or eight penicillin-resistant strains of Staphylococcus aureus (minimal inhibitory concentration, 0.2 mug/ml or less), but was found to have only a minimal in vivo activity against mouse Streptococcus infections.

Amides↗
PubMedDate not supplied

Delayed dedifferentiation and retention of properties in dissociated adult skeletal muscle fibers in vitro.

Adult skeletal muscle fibers can be isolated and cultured but tend to dedifferentiate and sprout with time in culture. We examined isolated adult mouse flexor digitorum brevis muscle fibers under various culture conditions by monitoring maintenance of the same fibers at 2-d intervals using survival analysis. Fibers plated on laminin and cultured in serum-free media did not show sprouting and exhibited significantly (P < 0.0001) longer survival (median survival time, T(50) = 10.2 d) than fibers in serum-containing media (T(50) = 3.3 d). Cell proliferation was markedly suppressed in serum-free cultures. Multiple or delayed Ca(2+) transients in response to brief field stimulation were often observed in dedifferentiated fibers after several d in serum-containing media but were not observed in fibers in serum-free media. The addition of cytosine arabinoside to serum-containing cultures did not prolong fiber survival (P = 0.39) and did not eliminate sprouting but did greatly suppress proliferation of nonmuscle cells. Fibers cultured in agarose gel with serum exhibited small, bud-like extensions but no sprouts and did not survive as long (T(50) = 6.2 d) as fibers plated on laminin and cultured in serum-free media (T(50) = 10.2 d) did. These results demonstrate that both morphological and physiological properties of fibers become modified in serum-containing media but can be retained by culturing without serum.

Animals↗
PubMedDate not supplied

'Manacled competition': market reforms in German health care.

In 1993 Germany joined the small but swelling ranks of societies determined to explore managed competition as a means of slowing the growth of health spending by giving stakeholders new incentives for efficiency. Realizing the benefits of competition, however, demands changes in institutional norms and regulatory practices that now largely handcuff those who would follow competitive logic into "managed care." In time Germany's system of "manacled competition" may evolve into a happy higher synthesis of managed care and managed competition. Or policymakers may conclude that the political price of installing workable market forces in health care is too high and reconcile themselves to more traditional applications of political pressure.

Cost Control↗
PubMedDate not supplied

Uneasy alliances: managed care plans formed by safety-net providers.

Health care providers that have traditionally served the poor are forming their own managed care plans, often in alliance with local safety-net peers. These alliances make it easier to raise needed capital, increase the pool of likely enrollees, and enable plans to benefit from efficiencies of scale. At the same time, however, the alliances often are undermined by conflicts of interest among the different sponsors and between the sponsors and the plan. This paper suggests that these plans are most likely to do well when the state makes special efforts to help and when plans have the leadership and financial reserves to take advantage of their supportive state policies.

Conflict of Interest↗
PubMedDate not supplied

Window shopping: state health reform politics in the 1990s.

Throughout the 1990s states sought politically acceptable policies to reduce the ranks of the uninsured. Visions of comprehensive health reform and universal coverage yielded by mid-decade to more modest measures to repair private health insurance markets, and to these enactments were added several new public programs (state and federal) to expand coverage for lower-income children and, in some cases, adults. Because governments remain ill equipped to counter the power of business, insurers, and providers in conflicts fought on private turf, reform agendas have been more readily set, moved, and cleared in public-sector arenas. Although the number of uninsured rose steadily until 1999, "catalytic federalism"--the accelerating interplay between state and federal reform forces and funds--may be putting the programmatic foundations for broader coverage incrementally into place.

California↗