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M Burke

Publications and source records attributed to M Burke.

At least 199 records · Page 11Linked to original sources
PubMed1991

Evidence for an anti-amnesic effect of JO 1784 in the rat: a potent and selective ligand for the sigma receptor.

JO 1784 ((+)-N-Cyclopropyl-methyl-N-methyl-1,4-diphenyl-1-yl-but-3-en-1-ylami ne, hydrochloride), has been recently described as a selective ligand for the sigma receptor with an IC50 of 39 +/- 8 nM28. In the present study the effects of JO 1784 on experimental induced amnesia were investigated using one trial passive avoidance task in rats. Amnesia was produced by injecting scopolamine (1 mg/kg i.p.) 30 min before the second session (T2) on day 2 of the passive avoidance task. The anti-amnesic effect of JO 1784 was compared with other typical and atypical psychotropic drugs which interact at the sigma and or the phencyclidine site. JO 1784 was studied at 5 doses; 0.0625, 0.25, 1.0, 4.0 and 16.0 mg/kg i.p. ((+)-3-(3-hydroxyphenyl)-N-1-(propyl)piperidine ((+)-3-PPP). Rimcazole, (+)-N-allylnormetazocine ((+)-NANM), 1,3-di(2-tolyl) guanidine (DTG) were studied at 4 doses; 0.25, 1.0, 4.0 and 8.0 mg/kg i.p. All drugs were administered 60 min before the test (T2) on day 2 i.e. 30 min before scopolamine. Piracetam (1000 mg/kg p.o.) administered in the same test conditions was used as a reference compound in each experiment. Of the drugs investigated JO 1784 (0.25, 1.0, 4.0 and 16.0 mg/kg i.p.), (+)-3-PPP (0.25, 1.0 and 4.0 mg/kg i.p.), DTG (1.0, 4.0 and 8.0 mg/kg) and piracetam significantly reversed scopolamine induced amnesia on day 3 (T3). At the lower dose, JO 1784 (0.0625 mg/kg) failed to reverse the amnesic effects of scopolamine on day 3. These results suggest that JO 1784 the selective sigma ligand, may be beneficial in amnesic status.

Amnesia↗
PubMed1991

Medicare appeals process offers hope for some hospitals.

For hospital officials who feel wronged by Medicare's payment system, a recent opportunity to appeal geographic status has stirred new hope for survival. Last September, the Health Care Financing Administration published interim final regulations detailing criteria hospitals have to meet to merit reclassification; hospitals had until Nov. 6, 1990, to file their appears. Now, officials are slogging through nearly 1,000 completed applications. "There has been pent-up demand for some review" of geographic classification, says one official.

Centers for Medicare and Medicaid Services, U.S.↗
PubMed1991

Hospitals tackle image problems at many levels.

A recent study of consumer attitudes shows that the public's perception of hospitals is hazy at best, and experts are warning hospitals to take steps to improve hospitals' image. In the following three articles, we examine the challenges facing hospitals in different arenas. First, we take a look at the consumer survey, which identifies the public's misperceptions about hospitals; then we focus on state hospital associations' ongoing efforts to enhance the image of hospitals by educating local lawmakers and consumers. Finally, we look at the American Hospital Association's ambitious new advocacy program to improve the health care community's ability to get its story across to the public and to policy-makers.

American Hospital Association↗
PubMed1991

Exceptions process becoming the norm for PPS-excluded providers.

The worsening financial condition of providers exempt from Medicare's prospective pricing system (PPS) is driving more of those hospitals to seek exceptions from their payment limits. A major problem inherent in the current pricing system for PPS-excluded providers is its original intent as a temporary solution, policy experts say. The AHA has warned HCFA that "major structural changes in the health care delivery system" are imperiling the survival of a good number of PPS-exempt hospitals. Or, in the words of the CEO of a PPS-exempt Philadelphia rehabilitation hospital, "We are all on a collision course with disaster, and some of us have already arrived."

Centers for Medicare and Medicaid Services, U.S.↗
PubMed1991

Medicaid expansion creates new dilemmas for state programs.

At the same time advocates for the poor are rejoicing over Medicaid program expansions passed as part of the FY 1991 federal budget, state Medicaid directors are wondering how to accommodate all the potential new recipients. Ironically, because of budget pressures at the state level, the new federal mandates could force some current program recipients off the rolls in order to allow new ones on. "Expanding obstetrical and prenatal care is something we want to do because it's sound social policy--but the mandates have been compressed into time frames that are too short for state budgets," says one state Medicaid director.

Budgets↗
PubMed1991

Identification of the site of photocross-linking formed in the absence of magnesium nucleotide from SH2 (Cys-697) in myosin subfragment 1 labeled with 4'-maleimidylbenzophenone.

The site of photocross-linking between Cys-697 (SH2), prelabeled with 4'-[14C]maleimidylbenzophenone, and the 50-kDa segment of myosin S1 on irradiation in the absence of nucleotide has been determined by isolation of the 20-50-kDa adduct and subsequent tryptic proteolysis. Isolation and partial sequencing of the radioactively labeled peptide indicate that the site of cross-linking is Arg-239. This result indicates that, in the absence of nucleotide, Arg-239 resides at about 1.0 nm from SH2 and, on the basis of the recent work of Sutoh and Hiratsuka (Sutoh, K. and Hiratsuka T. (1988) Biochemistry 27, 2964-2969) places Arg-239 at no more than 1.45 nm from either Lys-184 or Lys-189 of the nucleotide-binding "glycine-rich" loop prior to the binding of nucleotide.

Adenosine Diphosphate↗
PubMed1991

Tubal pregnancy.

Explore the source record for details and available documents.

Female↗
PubMed1991

Temperature-induced changes in the flexibility of the loop between SH1 (Cys-707) and SH3 (Cys-522) in myosin subfragment 1 detected by cross-linking.

The ability of dibromobimane to cross-link SH1 (Cys-707) in the 21-kDa C-terminal segment to SH3 (Cys-522) in the 50-kDa middle segment of the myosin S1 heavy chain has been examined as a function of nucleotide binding and temperature. The results obtained indicate that, while the reagent rapidly reacts with SH1 at both 25 and 4 degrees C, its ability to cross-link to SH3 is highly dependent on temperature. At 25 degrees C, substantial cross-linking from monofunctionally labeled SH1 to SH3 occurs, in agreement with recent work of Mornet, Ue, and Morales (1985, Proc. Natl. Acad. Sci, USA 82, 1658-1662) and of Ue (1987, Biochemistry 26, 1889-1894) and with their conclusion that a loop, allowing SH1 and SH3 to reside at the cross-linking span of dibromobimane, preexists in the protein. At 4 degrees C, however, negligible amounts of cross-linking are observed whether or not a nucleotide is present, despite indications that SH1 is labeled rapidly by the reagent at this temperature. The inability to form this cross-link is not due to an alternate cross-link between monofunctionally labeled SH1 and another thiol in the 21-kDa segment. These results indicate that this loop exists at 25 degrees C and does not exist (or exists only transiently) at the lower temperature.

Adenosine Diphosphate↗
PubMed1991

A 19-year-old man with leucocyte adhesion deficiency. In vitro and in vivo studies of leucocyte function.

We describe a male patient with leucocyte adhesion molecule deficiency (LAD) of moderate phenotype. Although diagnosis was made only 2 years before his death, the patient survived until 19 years of age. This enabled us to perform a number of novel investigation, both in vivo and in vitro, relating to his leucocyte biology. Monocytes cultured in vitro matured into morphologically normal, phagocytically capable macrophages, which were able to recognize aged 'apoptotic' neutrophils. By injection of radiolabelled autologous neutrophils we demonstrated a prolonged neutrophil half-life, but normal margination, de-margination on exercise, and splenic pooling. Neutrophil adherence in vitro to vascular endothelium was normal. Histological examination of the patient's lungs at post-mortem showed intravascular aggregation of polymorphonuclear leucocytes but a paucity of cells in the interstitium and alveolar spaces. These findings indicate that the peripheral blood leucocytosis commonly observed in these patients may be due to prolonged intravascular neutrophil survival, and suggest that CD11/18 molecules have an important role in facilitating neutrophil emigration from blood vessels at sites of inflammation.

Adult↗