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The emergence of integrated delivery networks provides an opportunity for leaders of patient care services to reach into our tool bags and refine the key leadership skills of strategist, facilitator, coach, and mentor. Shifting the focus from management to leadership is the hallmark of our success. As patient care leaders we will facilitate the achievement of the organization's strategic initiatives to improve clinical care delivery while decreasing cost. This article will explore the role of the patient care executive as part of the leadership team developing an integrated/organized delivery network.

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Digitonin is widely used for extracting active neurotransmitter receptors from membranes. However, its low critical micellar concentration has made its removal from samples problematic. Here we report that digitonin can be efficiently removed (> 90%) from solution using Extracti-Gel D, a detergent-absorbing matrix. Active kappa 1 opioid receptors solubilized from brain survive Extracti-Gel D chromatography with a recovery of 50-55% and 25% dilution by added volume. The loss of receptor and the dilution, however, are compensated for to a large extent by the disinhibition of binding that results from the removal of digitonin. Extracti-Gel D chromatography had little or no effect on the apparent equilibrium dissociation constant for [3H]U-69,593 binding to the kappa 1 receptor. We conclude that Extracti-Gel D column chromatography is a simple, highly efficient and practical method for markedly reducing the concentration of digitonin in biological samples. Application of the procedure should allow characterization of digitonin-solubilized receptors with minimal complications from bound digitonin and extend the usefulness of digitonin to studies going beyond the initial stages of receptor purification.

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[3H]Ethylketocyclazocine, in the presence of mu, delta and kappa-1 blocking agents, labels a high-affinity, saturable binding site in rat brain which we previously concluded might be the beta-endorphin-selective epsilon opioid receptor. However, studies failing to establish clearly the existence of the site in species other than rat raised the possibility that it might be an artifact or a unique constituent of rat tissues. Neither appears to be the case. We report here that, like other types of receptors, the site is proteinaceous with a sulfhydryl group within the binding site itself. Furthermore, the site appears to exist in two interchangeable, GTP-gamma-S-sensitive states which are readily distinguished by beta-endorphin, but not (-)-[3H]ethylketocyclazocine, and which are likely to be the site coupled to and uncoupled from a G protein. The putative epsilon receptor is not a peculiarity of rat brain but is readily measurable in forebrain of guinea pig, cow, chicken and pig brain as well. In fact, in all of the species examined, it is more abundant than mu, delta or kappa-1 receptors, representing 38 to 55% of the total opioid receptor population. The binding selectivity profile for drugs and the structure-activity relationship for beta-endorphin analogs indicated that the pharmacological properties of the putative epsilon receptor in brain are remarkably correlated with those of the epsilon receptor that was first hypothesized to exist in rat vas deferens and of the epsilon receptor that has been hypothesized to mediate the supraspinal analgesic effects of beta-endorphin.

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Maternal consumption of ethanol produces a pattern of malformations, including nervous system abnormalities, in the developing fetus, a state called Fetal Alcohol Syndrome. We report the dose-dependent inhibition by ethanol of the growth of a glioma derived cell line, C6 cells; the effects occur at ethanol concentrations commonly encountered in the blood during human intoxication. The effects occur with different morphological subtypes of the cell line and do not occur when the cells are exposed to iso-osmolar concentrations of other chemicals. The results demonstrate that C6 cells are a model for the study of the effects of ethanol on nervous system cell growth.

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A simple and highly sensitive assay for measuring total digitonin in biological samples is described. The assay is based on the ability of digitonin to hemolyze red blood cells. The precision and reproducibility of the assay was excellent with intra- and inter-assay variabilities of less than 1% and 6%, respectively. The assay was used to evaluate several potential methods for removing digitonin from biological samples (digitonin extracts from guinea pig brain membranes). Dialysis and G-25 Sephadex chromatography were ineffective. However, protein and digitonin can be effectively separated by ammonium sulfate precipitation followed by dialysis. The kappa 1 opioid receptor survived these procedures with no change in affinity for [3H]U-69,593. In conclusion, the hemolytic assay for digitonin appears to provide a practical means for determining detergent concentrations during receptor purification and characterization and for evaluating potential methods for detergent removal. Although an in depth analysis of the assay was carried out only for digitonin, CHAPS and deoxycholate also caused 50% hemolysis at concentrations well below those commonly used for receptor solubilization and, therefore, the general assay procedures might have applicability for measurement of these and perhaps other detergents used in receptor solubilization as well.

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Alcohol metabolism in the human brain has been characterized as essentially nonoxidative in nature, with the esterification of ethanol with fatty acids via fatty acid ethyl ester synthase. This pathway of ethanol metabolism is related to end organ damage in the brain but the neural cell type expressing FAEES has not been identified. In this study human and rodent neuroblastoma and glioma cell lines are assayed for fatty acid ethyl ester synthase activity. Cells with neuronal properties demonstrated higher activity than glioma cell lines. We confirmed the presence of the mRNA for one type of synthase, fatty acid ethyl ester synthase-III in three neuronal cell lines--N1E115 cells, PC12 cells, and SK-N-MC cells. These results support the hypothesis that FAEES activity is expressed chiefly in cells with neuronal properties and suggest that non-oxidative ethanol metabolism is potentially related to the toxic effect of ethanol on the human brain.

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We used polyclonal antisera recognizing S100, a small acidic protein highly enriched in nervous tissue, to stain sections of embryonic chicken lumbosacral spinal cord and hindlimb. S100 immunoreactivity was detected in developing sensory neurons of the dorsal root ganglia (DRG) and motor neurons of the ventral spinal cord as early as embryonic day (E) 5, and staining persisted through hatching. In contrast, expression of S100 first became apparent in Schwann cells at E13, just before myelination, and was not detected in developing skin or muscle. Since S100 beta was present in motor and sensory neurons and is known to promote neuronal survival and neurite extension in vitro (Winningham-Major, Staecker, Barger, Coats, and Van Eldik, 1989), we tested the ability of S100 to promote neuron survival in an in ovo survival assay. Addition of S100 to chick embryos in ovo during the period of naturally occurring motor neuron cell death resulted in a significant increase in motor neuron survival, but had no effect on the in vivo survival of sensory neurons in the DRG. The findings that S100 is present in spinal motor neurons and that the addition of S100 enhances the survival of these cells in vivo are consistent with the possibility that S100 may act as a naturally occurring neuron survival factor during development.

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A procedure was worked out for purification and identification of calcium-binding proteins from bovine brain using Ca2+-dependent, reversible binding to a hydrophobic support, phenyl-Sepharose, as the method of isolation. These proteins could be visualized during and after their separation by running them on non-denaturing polyacrylamide gels, blotting to Zeta-probe paper, and autoradiographing with 45Ca2+. About 24 polypeptides could be seen in this fraction on SDS (Laemmli) gels and about 8-10 native, Ca2+-binding proteins could be seen on non-denaturing gels and on blots of their 45Ca2+ autoradiographs. Some of these proteins could be purified further by chromatography on DEAE-Sephacel and still retain their 45Ca2+-binding activity.

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The binding of Ca2+ to rat or bovine S-100 proteins, in the absence of ligands, showed a dissociation constant (in 60 mM K+) of 0.5 to 1.0 mM as measured by the effects of Ca2+ on binding of S-100 to phenyl-Sepharose, reactivity of sulfhydryl groups, and difference spectra for PHE, TYR, and TRP residues. Binding of the ligands, "Stainsall" and chlorpromazine lowered the dissociation constant of S-100 for Ca2+ by 2- to 10-fold as measured by the same parameters. The conformational change, in response to Ca2+ binding, probably occurs by exposure to solvent of the hydrophobic region of alpha and beta subunits of S-100 at residue positions 74-93.

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The S-100 nervous system protein was purified from bovine and rat brains by a modification of the original procedure. The main modification consisted in substituting a step of calcium-dependent binding of S-100 to a phenyl-Sepharose column for the original step of chromatography on G-200 Sephadex. The proteins were pure as determined by SDS gel electrophoresis. HPLC on a reversed phase and on a size-separation column, and by immunological criteria. The bovine S-100 behaved as previously described, during calcium binding, by displaying a conformational change as evidenced by increase in native fluorescence.

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Commercially available Coomassie Brilliant Blue R-250 (C.I. 42660) is a popular and useful dye that stains most proteins blue on polyacrylamide gels. Some proteins from brain (rubrophilin), collagens, histones and parotid gland proteins are distinctly red when stained with Coomassie Blue. Commonly used Coomassie Brilliant Blue R-250 preparations may contain more than 30 distinct colored and fluorescent components that can be separated on silica gel chromatographic columns. A specific component has been isolated on silica gel columns that stains rubrophilin and other proline-rich proteins a reddish color. Fast atom bombardment mass spectrometry of the isolated rubrophilin staining principle indicates a molecular weight of 634 as compared to 826 for the major dye in the original Coomassie Brilliant Blue R-250. Infrared spectrometry is consistent with a difference between the rubrophilin staining principle and Coomassie Brilliant Blue R-250 of a toluene sulfonic acid residue.

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Effervescent lozenges containing 10 mg of zinc acetate were evaluated as a treatment of upper respiratory tract infections in a double-blind randomized trial by using a placebo which was indistinguishable to most observers in taste and appearance from the active material. Of the 70 treatment courses used by 55 individuals in 34 families, 63 (33 zinc and 30 placebo) were considered evaluable, in that the volunteer used the medication at least four times daily for at least 3 days, the average utilization being 5.4 days at an average dose of six lozenges daily. Six users of zinc reported nausea (versus no placebo users), and eight reported an unpleasant taste or aftertaste (versus one placebo user). No benefit was observed among the users of zinc acetate. The mean duration of symptoms in users of the zinc was 12.1 days, compared with 7.7 days in those who used the placebo. Nor was any beneficial effect of zinc evident among the four zinc-treated versus the two placebo-treated individuals from whom rhinovirus was grown.

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Rubrophilin, a unique brain specific polypeptide, was purified to apparent homogeneity from microsomal fractions of bovine brains. The peptide stains pink with Coomassie Brilliant Blue R-250 (C.I. No. 42660) under specific conditions, has an apparent Mr of 53,000, and is acidic with an apparent pI of 4.9. The purification involves initial solubilization of delipidated microsomes in sodium dodecyl sulfate, followed by ammonium sulfate fractionation, reversed ammonium sulfate gradient elution from diatomaceous earth, gel filtration on polyacrylamide (Biogel P-200), gradient elution chromatography from hydroxylapatite, and reverse-phase chromatography from phenyl-Sepharose. A yield of about 5 mg of rubrophilin was obtained from 9 g of microsomal proteins. Amino acid analysis shows that rubrophilin contains only nine amino acids with residues/mol as follows: alanine (102), glutamic acid (97), lysine (65), proline (55), aspartic acid (48), glycine (44), serine (37), threonine (35), and valine (10). Cysteine, methionine, tryptophan, tyrosine, isoleucine, phenylalanine, histidine, and arginine could not be detected. Relative rubrophilin content of vertebrate brains was as follows: mammals greater than birds greater than reptiles greater than fishes. It is present in mouse retina and human neuroblastoma cell cultures but could not be detected in octopus optic lobe or in cultured C-6 rat glioma cells.

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The protein organization of rat brain synaptic plasma membranes (SPM) and synaptic vesicles (SV) was investigated by surface iodination and one- and two-dimensional electrophoresis. Polypeptides of molecular weights (MWs, in Kilodaltons) 170 K, 135 K, 96-86 K, 68-64-61 K, 56 K, 52 K, 38 K, 35-33 K, and 18 K are predominantly or exclusively exposed on the extracellular side of synaptosomes. Several polypeptides of MW between 70 K and 40 K are exclusively exposed on the cytoplasmic side of SPM. The use of two-dimensional electrophoresis allowed to recognize that, for some classes of MW, there are polypeptides of nearly the same MW and different isoelectric points exposed on both sides of SPM. The synaptosomal membrane shows a predominance of acidic proteins on the extracellular side and more neutral and basic proteins on the cytoplasmic side. With respect to SPM, SV are particularly enriched with polypeptides of MW 71 K, 56 K, 39-38 K, 32 K, 16 K, and 15 K. One of them, a doublet of MW 39-38 K, is the most highly labeled species upon surface iodination and is similar, but not identical, with a doublet located on the cytoplasmic side of SPM.

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The clinical manifestations and laboratory findings of two patients with a presumptive diagnosis of coxsackie B4 virus infection are described. A striking feature was the similarity with adult onset Still's disease, with spiking fever, evanescent macular rash, and severe polyarthritis. This latter feature persisted for many weeks and required steroids to control the symptoms. Review of the literature has supported the proposition that many cases of adult onset Still's disease may be due to coxsackie B4 or other viral infection and it is suggested that these agents should be actively sought in future cases.

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In a double-blind evaluation of alpha 2-interferon as prophylaxis against naturally acquired respiratory infections, 120 adult members of 46 Australian families used 325 courses of intranasal spray during a six-month period, applying 5 million IU to the anterior nasal mucosa daily for seven days when respiratory symptoms developed in another member of the family. Used in this way, the alpha 2-interferon was well tolerated, and the rate of minor nasal bleeding (12 percent) did not increase with repeated courses. By comparison with the control group of 109 members of 49 families who used 319 seven-day courses of placebo spray, the users of alpha 2-interferon experienced 33 percent fewer days with nasal symptoms and 41 percent fewer episodes of "definite" respiratory illness. The users of alpha 2-interferon who were exposed to rhinovirus infections experienced 76 percent fewer days with symptoms and 86 percent fewer "definite" illnesses than their counterparts who used placebo. All of the observed clinical benefits, which suggested prevention of 6.8 "definite" respiratory illnesses per 100 courses of medication used, could be explained by a protective effect against illness associated with rhinoviruses that was not demonstrated for influenza A or B or coronavirus 229E.

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Numbers of deaths from pneumonia and influenza and other causes were analysed for successive four-week periods in South Australia during 1968-1981. An overall excess in deaths from pneumonia or influenza of 74% was evident during the winter months and early spring, compared with summer and early autumn. An accompanying excess of 18% occurred for deaths assigned to other causes. There was a strong association between numbers of deaths from pneumonia and influenza and other deaths, suggesting that influenza may have a broad impact on mortality. This mostly applied to individuals aged 60 years and over. There is the need for medical practitioners to provide prophylactic care to protect aged patients against the effects of influenza. This should be done in autumn, and special attention should be given to individuals with underlying conditions.

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Extracellular protein fractions were obtained (1) by mild, isotonic irrigation of freshly perfused brain tissue; (2) by collection of proteins released into superfusing medium by physiologically viable slices of rat hippocampus; and (3) by sampling the CSF of anesthetized rats. Analysis of the S-100 protein content of these fractions gave values of 2.8, 4.2, and 1.8 micrograms S-100/mg protein, respectively. These values were three- to sixfold higher than the S-100 content of the soluble cytoplasmic protein fractions from the same tissue. This several-fold higher S-100 content of the extracellular protein fractions relative to the intracellular cytoplasmic protein fractions indicates that S-100 is selectively released into the extracellular spaces of the brain. We suggest that the biological function of this CNS protein may involve intercellular transfer.

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The distribution of S-100 outside the central nervous system in humans and rats was explored using antiserum to S-100 and the peroxidase anti-peroxidase method of Sternberger. In peripheral nerves the Schwann cells and the outermost part of the myelin sheaths were stained; axons were not. In dorsal root ganglia and ganglia of the autonomic nervous system only satellite cells were stained. In the adrenal medulla a considerable number of cells were stained. In all other organs studied Schwann cells and satellite cells of ganglia were the only elements that were stained. We conclude that S-100 could serve as a marker for Schwann cells in situ.

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