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C Mays

Publications and source records attributed to C Mays.

7 recordsLinked to original sources

1999 facility Profile Reports.

In November 1999, the Mid-Atlantic Renal Coalitions (MARC) developed and distributed its first version of a facility-specific Profile Report to the medical directors and head nurses of dialysis facilities in Washington, DC, Maryland, Virginia, and West Virginia. The profiles were distributed to support the facilities' internal quality improvement efforts and were not intended to be released as public documents. Facility characteristic and profiling indicators were selected based on the availability, reliability, and value of the data. The Profile Report consisted of 2 data displays with corresponding definition tables. An evaluation mechanism was discussed, but it was determined that the initial report would not be formally evaluated and that this would be included as a feature of future versions. Future versions will be expanded, as additional data become available, and will include rankings and data trending where appropriate.

Ambulatory Care Facilities↗

Motor dysfunction after spinal cord injury is mediated by opiate receptors.

Naloxone, an opiate receptor antagonist, improves neurological outcome following traumatic cervical spinal cord injury in the cat and ischemic lumbar spinal cord injury in the rabbit. However, the doses of naloxone required have been quite high (greater than 1 mg/kg), suggesting that its beneficial actions are either not opiate receptor mediated or mediated by non-mu opiate receptors (which are less naloxone-sensitive). The kappa receptor appears to be the predominant opiate receptor in the spinal cord in a variety of species. For these reasons we evaluated the effects of a somewhat kappa selective opiate receptor antagonist WIN44,441-3 [WIN(-)] on neurological recovery following traumatic spinal injury in the cat and ischemic spinal injury in the rabbit. Animals treated with this more selective antagonist showed improved motor recovery as compared with animals treated with either physiological saline or with the dextroisomer of the WIN compound [WIN44,441-2; WIN(+)]. These findings support the hypothesis that motor dysfunction after spinal cord injury is in part mediated by opiate receptors and indicate that kappa selective opiate receptor antagonists may have particular therapeutic utility in spinal cord injury.

Animals↗

Characterization of pepsin-resistant collagen-like tail subunit fragments of 18S and 14S acetylcholinesterase from Electrophorus electricus.

Digestion of 18S and 14S acetylcholinesterase from eel electric organ with pepsin at 15 degrees C for 6 h results in extensive degradation of the catalytic subunits, but a major portion of the collagen-like tail structure associated with these enzyme forms resists degradation. The pepsin-resistant structures partially aggregate and can be isolated by gel exclusion chromatography on Sepharose CL-6B in buffered 1 M sodium chloride. The largest structure, denoted F3, has a molecular weight of 72 000 according to gel electrophoresis in sodium dodecyl sulfate and is composed of three 24 000 molecular weight polypeptides linked by intersubunit disulfide bonds. This structure is largely, but not completely, a collagen-like triple helix as indicated by a circular dichroism spectrum typical of triple-helical collagen and an amino acid composition characterized by 27% glycine, 5% hydroxyproline, and 5% hydroxylysine. Continued pepsin action results in degradation of the disulfide linkage region such that disulfide-linked dimers F2 and finally F1 monomers become the predominant forms in sodium dodecyl sulfate. Digested samples in which either F3 or F2 predominate have virtually identical circular dichroic spectra and amino acid compositions and generate similar diffuse 24 000 molecular weight polypeptides following disulfide reduction. Thus the intersubunit disulfide linkages in F3 must occur close to the end(s) of the fragment polypeptide chains. Pepsin conversion of F3 to F2 is particularly accelerated between 25 and 30 degrees C, suggesting that the triple-helical structure in the disulfide linkage region undergoes thermal destabilization in this temperature range. Digestion at 40 degrees C yields presumably triple-helical F1 structures devoid of disulfide linkages, although their degradation to small fragments can be detected at this temperature. The question of whether the three tail subunits that give rise to F1 polypeptides are identical remains open.

Acetylcholinesterase↗

Lipoprotein metabolism in nonresponders to increased dietary cholesterol.

We have studied the effect of increased dietary cholesterol on production and degradation of plasma very low density lipoproteins and low density lipoproteins. We studied five unselected normal volunteers who were on weight-maintaining diets consisting of 45% carbohydrate, 40% fat, and 15% protein with a ratio of polyunsaturated to saturated fat of 0.4. Cholesterol content was 150 mg/1000 kcal in Period A and 500 mg/1000 kcal in Period B. Subjects were fed each diet for 4 to 5 weeks. The turnover of apoproteins B in very low density and low density lipoproteins and of triglyceride in very low density lipoproteins were measured during the last 2 weeks of each study period using 131I-labeled very low density lipoproteins and 125I-labeled low density lipoproteins and 2-3H-glycerol, respectively. There was no significant change in plasma total cholesterol or triglycerides or in low density lipoprotein cholesterol levels during the high cholesterol versus the low cholesterol diet. Similarly, high cholesterol intake had no effect on the rate of production or clearance of apo B in very low density and low density lipoproteins or of triglyceride in very low density lipoproteins. These data indicate that the flux of very low density lipoproteins does not change in nonresponders to high cholesterol diets.

Adult↗