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A Chapman

Publications and source records attributed to A Chapman.

At least 145 records · Page 8Linked to original sources
PubMed1979

Structure of the high mannose oligosaccharides of a human IgM myeloma protein. I. The major oligosaccharides of the two high mannose glycopeptides.

The structures of the predominant high mannose oligosaccharides present in a human IgM myeloma protein (Patient Wa) have been determined. The IgM glycopeptides, produced by pronase digestion, were fractionated on DEAE-cellulonalysis shows that glycopeptide I contains Asn, Pro, Ala, Thr, and His and glycopeptide II contains Asn, Val, and Ser, which are the same amino acids found in the sequences around Asn 402 and Asn 563 respectively, to which high mannose oligosaccharides are attached in IgM (Patient Ou) (Putnman, F.W., Florent, G., Paul, C., Shinoda, T., and Shimizu, A. (1973) Science 182, 287-290). The high mannose glycopeptides in IgM (Wa) exhibit heterogeneity in the oligosaccharide portion. Structural analysis of the major oligosaccharides indicates that the simplest structure is: (see article of journal). The larger oligosaccharides present have additional mannose residues linked alpha 1 yields 2 to terminal mannose residues in the above structure. Glycopeptide I contains primarily Man5 and Man6 species, while glycopeptide II contains Man6 and Man8 species. The two Man6 oligosaccharides have different branching patterns.

Amino Acids↗
PubMed1979

Structure of the high mannose oligosaccharides of a human IgM myeloma protein. II. The minor oligosaccharides of high mannose glycopeptide.

The high mannose glycopeptide I from IgM (Patient Wa) contains, in addition to the two major oligosaccharides described earlier (Chapman, A., and Kornfeld, R. (1979) J. Biol Chem. 254, 816-823), four minor oligosaccharides. After release from glycopeptide I by endo-beta-N-acetylglucosaminidase Cu and reduction with NaBH4, all four oligosaccharides have been shown to have the basic structure: (see article of journal). Oligosaccharide IA-1 (Man9GlcitolNAc) has additional alpha1,2-linked mannose residues attached to positions a and b, and the sequence Man alpha1,2 yields to Man alpha1,2 yields to attached at position c. Oligosaccharide IA-2 (Man8GlcitolNAc) has additional alpha1,2-linked mannose residues attached to positions a, b, and c. Oligosaccharide IA-3 (Man7GlcitolNAc) has additional alpha1,2-linked mannose residues at positions b and c. In contrast, oligosaccharide IA-4 has a single N-acetyglucosamine residue beta1,2-linked to the mannose at position c. Oligosaccharides IA-1, -2 and -3 are thought to represent "processing" intermediates that are precursors of the major Man6 and Man5 oligosaccharides of glycopeptide I. IA-4 may arise from the Man5 oligosaccharide by the action of UDP-GlcNAc:glycoprotein N-acetylglucosaminyl-transferase, which catalyzes the first reaction leading to complex oligosaccharide synthesis.

Carbohydrates↗
PubMed1979

Terra firma.

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Crime↗
PubMed1978

Increased glomerular filtration rate in patients with major burns and its effect on the pharmacokinetics of tobramycin.

The clearance of endogenous creatinine in 20 burned patients, measured between the fourth and the 35th post-burn day, was a mean (+/- S.D.) of 172.1 p 48.4 ml per minute per 1.73 m2; in eight normal subjects the mean value was 125.4 g- 10.4 (P less than 0.02). Thirteen patients had values more than 2 S.D. above the normal mean. We confirmed this rise in glomerular filtration rate by measuring inulin or iothalamate clearance in nine patients. The pharmacokinetics of tobramycin were studied in 11 of the 20 patients and in eight normal subjects receiving continuous intravenous infusions of the drug. An inverse correlation was found between plasma half-life of the drug and creatinine clearance (r = 0.68, P less than 0.01). Increased creatinine clearances and shortened half-life of tobramycin occurred mainly in younger patients. Glomerular filtration rates in burned patients may rise to very high values and can be validly measured by creatinine clearance. The plasma half-lives of drugs with predominantly urinary excretion may decrease in patients with burns.

Adult↗
PubMed1978

Effect of high dose d-l propranolol on the renin-angiotensin system in glycerol induced acute renal failure in rat.

Stimulation of the renin-angiotensin system has been implicated in the pathogenesis of post-ischemic and nephrotoxic acute renal failure. This study was designed to determine the effect of d-l propranolol in glycerol induced acute renal failure in rats. 50% glycerol administered alone, induced a significant rise in blood urea and plasma renin concentration but no significant change in renal renin concentration. When administered with d-l propranolol (10 mg/kg body weight in 5 subcutaneous injections), mean blood urea, plasma renin and renal renin concentrations were not significantly different from the preceding group. Propranolol alone, administered in the same fashion, unexpectedly induced a rise in plasma renin concentration (p less than 0.05) while blood urea and renal renin concentrations were unchanged. Considering the unusually high dose of propranolol used, a second protocol was devised to compare the effects of d-l propranolol, in doses of 10 mg/kg and 1 mg/kg. Plasma renin concentration rose after high dose propranolol, but decreased, although not significantly, after administration of 1 mg/kg. Renal renin concentration was unchanged. High dose d-l propranolol, does not protect rats against glycerol induced acute renal failure. Contrarily to the usual 1 mg/kg dose, it was found surprisingly to increase renin release.

Acute Kidney Injury↗
PubMed1977

[Preventive treatment of acute renal failure in cardiac surgery].

The prevention of acute renal failure after cardiac surgery under extracorporeal circulation is possible during the pre-, per- and post-operative phases. During "ECC" the maintenance of "correct" renal perfusion is imperative, the same is also true of the post-operative period; the re-establishment of good hemodynamics is the best guarantee of maintenance of renal function. The prevention of infection is the second imperative.

Acute Kidney Injury↗