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C Fuller

Publications and source records attributed to C Fuller.

At least 37 records · Page 2Linked to original sources
PubMed1996

Effect of alpha-tocopherol on LDL oxidation and glycation: in vitro and in vivo studies.

Much data support a role for both low density lipoprotein (LDL) oxidation and glycation in atherogenesis. While alpha-tocopherol decreases the oxidative susceptibility of LDL, its role in decreasing LDL glycation is unclear. Hence we tested the effect of alpha-tocopherol both in vitro and in vivo on LDL oxidation and glycation. LDL was isolated after enrichment of plasma with alpha-tocopherol. This resulted in a 2-fold increase in alpha-tocopherol in LDL (AT-LDL). During a 6-day incubation of control LDL (C-LDL) and AT-LDL with 25 mM glucose, there were no significant differences in the degree of glycation on days 1, 3, and 6. Also, apoB advanced glycosylation end product levels were not significantly different between C-LDL and AT-LDL. There was a progressive increase in the susceptibility of LDL to oxidation with increasing LDL glycation as evidenced by reduced lag time of copper-catalyzed LDL oxidation. However, AT-LDL was more resistant to copper-catalyzed oxidation. Similar findings were observed when the LDLs were incubated with endothelial cells. The data from the alpha-tocopherol supplementation study confirmed our in vitro findings that alpha-tocopherol significantly decreases oxidative susceptibility of LDL, but does not affect its glycation. Therefore, while glycation increases LDL oxidative susceptibility, alpha-tocopherol decreases the oxidation of glycated LDL but not LDL glycation.

Arteriosclerosis↗
PubMed1995

Volume-associated osmolyte fluxes in cell lines with or without the anion exchanger.

To investigate the involvement of a red cell-type anion exchanger in the volume-sensitive amino acid release, the hyposmolarity-evoked release of D-[3H]aspartate and [3H]taurine was examined in three cell lines: 1) wild-type Chinese hamster ovary (CHO-K1) cells, expressing an anion exchanger activity (Cl-/SO4(2-)) functionally similar to the erythroid band 3; 2) a mutant CHO cell type (CHO 605) lacking this anion exchanger activity; and 3) 293 cells in which the Cl-/HCO3(-) anion exchanger is absent. All cell types accumulated D-[3H]aspartate and [3H]taurine under isosmotic conditions, and, similarly, in the three cell lines, cell swelling evoked by hyposmolarity induced a rapid and transient increase in the amino acid efflux. Blockers of the anion exchanger and/or Cl- channels [niflumic acid, dipyridamole, diphenylamine-2-carboxylate,5-nitro-2-(3-phenylpropylamino)-benzoi c acid, and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid] were potent inhibitors of amino acid efflux in the three cell lines. 125I- efflux, used as a marker for Cl- fluxes, was also markedly increased in response to cell swelling in all cell lines, and this efflux was inhibited by the anion exchanger/Cl- channel blockers. These results do not support a role for an anion exchanger in the hyposmolarity-induced amino acid efflux and suggest that amino acids and Cl- may be transported by the same or a similar mechanism, presumably an anion channel-like structure.

Animals↗
PubMed1994

The peripheral subunit-binding domain of the dihydrolipoyl acetyltransferase component of the pyruvate dehydrogenase complex of Bacillus stearothermophilus: preparation and characterization of its binding to the dihydrolipoyl dehydrogenase component.

The peripheral subunit-binding domain of the dihydrolipoyl acetyltransferase polypeptide chain of the pyruvate dehydrogenase multienzyme complex of Bacillus stearothermophilus was released by limited proteolysis from a di-domain (lipoyl domain plus binding domain) encoded by a subgene over-expressed in Escherichia coli. The domain was characterized by N-terminal sequence analysis, electrospray m.s. and c.d. spectroscopy. It was found to be identical in all respects to a chemically synthesized peptide of the same sequence. The association of the di-domain and binding domain (both natural and synthetic) with dihydrolipoyl dehydrogenase was analysed in detail and a tight binding was demonstrated. As judged by several different techniques, it was found that only one peripheral subunit-binding domain is bound to one dimer of dihydrolipoyl dehydrogenase, implying that the association is highly anti-cooperative.

Amino Acid Sequence↗
PubMed1991

Three DNA sequencing methods using capillary gel electrophoresis and laser-induced fluorescence.

Capillary gel electrophoresis is demonstrated for the four-spectral-channel sequencing technique of Smith, the two-spectral-channel sequencing technique of Prober, and the one-spectral-channel sequencing technique of Richardson and Tabor. Sequencing rates up to 1000 bases/h are obtained at electric field strengths of 465 V/cm. At lower electric field strengths, capillary electrophoresis produces useful data for fragments greater than 550 nucleotides in length with 2 times better resolution than slab gel electrophoresis. An on-column detector produces detection limits of 200 zmol (1 zmol = 10(-21) mol = 600 molecules) for the four-spectral-channel technique. A postcolumn detector, based on the sheath flow cuvette, produces detection limits of 20 and 2 zmol for the two- and one-spectral-channel techniques, respectively.

Base Sequence↗
PubMed1991

Systemic lupus erythematosus in adolescents.

Once considered a rare, fatal illness in children and adolescents, systemic lupus erythematosus (SLE), or lupus, is now understood to be a relatively common chronic disorder in these age groups. This article provides a brief overview of the disease, describing its etiology, pathology, clinical manifestations, diagnosis, and treatment. A case history of an adolescent girl with lupus is presented, and the role of the nurse is discussed in relation to promoting four developmental tasks of adolescents: developing a positive body image, establishing a sexual identity, achieving independence, and acquiring formal thought processes. Since lupus interferes to some degree in the accomplishment of these tasks, we suggest methods of assessment and intervention that the nurse can use in each area to overcome these interferences.

Adolescent↗
PubMed1991

Autoantibodies in primary biliary cirrhosis: analysis of reactivity against eukaryotic and prokaryotic 2-oxo acid dehydrogenase complexes.

Six components of the mammalian 2-oxo acid dehydrogenase complexes have previously been identified as M2 autoantigens in primary biliary cirrhosis. In this report, we present data showing that both polypeptide-specific and cross-reacting antibodies are present in patients' sera. Antibodies reacting with E2 of the pyruvate dehydrogenase complex cross-react with protein X but not with any other mammalian antigen. The main immunogenic region on protein X has been localized to within its single lipoyl domain. Polypeptide-specific antibodies bind to E1 alpha and E1 beta of the pyruvate dehydrogenase complex. Antibodies reacting with the E2 polypeptides of the 2-oxoglutarate dehydrogenase complex and branched-chain 2-oxo acid dehydrogenase complex show some cross-reactivity but do not recognize any of the antigens of the pyruvate dehydrogenase complex. Antibodies against the E2 component of the mammalian pyruvate dehydrogenase complex cross-react effectively with the corresponding protein from yeast but not with E2 from Escherichia coli. Antibody titer against mammalian antigens is significantly higher than against the bacterial antigens, arguing against a bacterial origin for primary biliary cirrhosis.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗
PubMed1986

Management of cystine nephrolithiasis with alpha-mercaptopropionylglycine.

The effect of long-term treatment with alpha-mercaptopropionylglycine was examined in 66 patients with cystinuria. Of the patients 49 took D-penicillamine before therapy, whereas 17 did not. Over-all side effects to alpha-mercaptopropionylglycine were common, and occurred in 75.5 per cent of the patients with and 64.7 per cent without a history of D-penicillamine treatment, compared to 83.7 per cent who suffered toxicity to D-penicillamine. Serious adverse reactions requiring cessation of therapy were less common with alpha-mercaptopropionylglycine. Among the patients who took both drugs 30.6 per cent had to stop taking alpha-mercaptopropionylglycine, whereas 69.4 per cent could not tolerate D-penicillamine. Of the latter group with toxicity to D-penicillamine before therapy, whereas 17 did therapy only 5.9 per cent had side effects to alpha-mercaptopropionylglycine of sufficient severity to require withdrawal. Alpha-mercaptopropionylglycine was equally as effective as D-penicillamine in reducing cystine excretion. During long-term treatment with alpha-mercaptopropionylglycine (average dose 1,193 mg. per day) urinary cystine levels were maintained at 350 to 560 mg. per day and urinary cystine was kept at undersaturated levels. Commensurate with these changes, alpha-mercaptopropionylglycine produced remission of stone formation in 63 to 71 per cent of the patients and reduced individual stone formation rate in 81 to 94 per cent. Thus, alpha-mercaptopropionylglycine has a definite therapeutic role in cystinuric patients with toxicity to D-penicillamine.

Adolescent↗
PubMed1986

Successful management of uric acid nephrolithiasis with potassium citrate.

Eighteen patients with uric acid nephrolithiasis (six with uric acid stones alone and 12 with both uric acid and calcium stones) underwent long-term treatment (1 to 5.33 years, mean of 2.78 years) with potassium citrate (30 to 80 mEq/day, usually 60 mEq/day). Urinary pH increased from low (5.30 +/- 0.31 SD) to normal (6.19 to 6.46) during treatment. Urinary content of undissociated uric acid, which was high to begin with at 204 +/- 82 mg/day, decreased to the normal range (64 to 108 mg/day) following treatment. Urinary citrate rose from 503 +/- 225 mg/day to 852 to 998 mg/day. Urinary saturation of calcium oxalate significantly declined with potassium citrate treatment. New stone formation rate declined from 1.20 +/- 1.68 stones/year to 0.01 +/- 0.04 stones/year (P less than 0.001 by chi square). Remission was experienced in 94.4% of patients, and the group stone formation rate declined by 99.2%. Detailed case reports were obtained in five patients showing different responses between sodium alkali and potassium alkali treatment. All five patients had persistently low urinary pH (typically less than 5.5) and normouricosuria, and four had hyperuricemia. Before treatment, they had stones surgically removed or spontaneously passed, which were pure uric acid in composition. When sodium alkali was give (as bicarbonate or citrate, 60 to 118 mEq/day), new stone formation continued in four patients, and a radiolucent (uric acid) calculus become "calcified" in the remaining patient. The stone analysis disclosed calcium oxalate in five patients and calcium phosphate in three patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Idiopathic hypocitraturic calcium-oxalate nephrolithiasis successfully treated with potassium citrate.

The effects of long-term treatment with potassium citrate, 30 to 80 meq/d over 2.13 +/- 0.76 (SD) years, were examined in 37 patients with "idiopathic" hypocitraturic calcium-oxalate nephrolithiasis, in whom the main causes of hypocitraturia (renal tubular acidosis, chronic diarrhea, urinary tract infection, or hypokalemia) were excluded or considered unlikely. Potassium citrate treatment produced a sustained increase in urinary citrate excretion from initially low values (223 to 253 mg/d) to within normal limits (470 to 620 mg/d). Urinary pH rose significantly and was maintained at 6.5 to 7.0. Along with these changes, urinary saturation of calcium oxalate declined significantly to normal limits. Further stone formation ceased in 89.2% of patients during treatment, and the stone formation rate declined from 2.11 +/- 5.68 to 0.28 +/- 1.30 stones/patient-year (p less than 0.01).

Adult↗
PubMed1985

Correction of hypocitraturia and prevention of stone formation by combined thiazide and potassium citrate therapy in thiazide-unresponsive hypercalciuric nephrolithiasis.

Thirteen patients with hypercalciuric calcium nephrolithiasis continued to form calcium stones when treated with thiazide (4.69 +/- 6.62 [mean +/- SD] stones per patient-year to 5.12 +/- 10.87 stones per patient-year), despite adequate hypocalciuric response (a reduction in urinary calcium levels from 303 +/- 119 mg per day to 193 +/- 88 mg per day, p less than 0.01). Because they had hypocitraturia (250 +/- 86 mg per day versus 643 +/- 236 mg per day in normal subjects, p less than 0.001), potassium citrate (10 to 20 meq three times per day) was added to the ongoing treatment program. During combined treatment with thiazide and potassium citrate, urinary pH significantly rose, and normal levels of urinary citrate were restored. Ten patients stopped forming new stones and all 13 had reduced stone formation rate. Thus, potassium citrate supplementation should be considered in patients requiring thiazide therapy for the control of hypercalciuric nephrolithiasis, especially if they have concurrent hypocitraturia or if it develops during thiazide therapy.

Adult↗
PubMed1985

Long-term treatment of calcium nephrolithiasis with potassium citrate.

The long-term effects of potassium citrate therapy (usually 20 mEq. 3 times daily during 1 to 4.33 years) were examined in 89 patients with hypocitraturic calcium nephrolithiasis or uric acid lithiasis, with or without calcium nephrolithiasis. Hypocitraturia caused by renal tubular acidosis or chronic diarrheal syndrome was associated with other metabolic abnormalities, such as hypercalciuria or hyperuricosuria, or occurred alone. Potassium citrate therapy caused a sustained increase in urinary pH and potassium, and restored urinary citrate to normal levels. No substantial or significant changes occurred in urinary uric acid, oxalate, sodium or phosphorus levels, or total volume. Owing to these physiological changes, uric acid solubility increased, urinary saturation of calcium oxalate decreased and the propensity for spontaneous nucleation of calcium oxalate was reduced to normal. Therefore, the physicochemical environment of urine following treatment became less conducive to the crystallization of calcium oxalate or uric acid, since it stimulated that of normal subjects without stones. Commensurate with the aforementioned physiological and physicochemical changes the treatment produced clinical improvement, since individual stone formation decreased in 97.8 per cent of the patients, remission was obtained in 79.8 per cent and the need for surgical treatment of newly formed stones was eliminated. In patients with relapse after other treatment, such as thiazide, the addition of potassium citrate induced clinical improvement. Thus, our study provides physiological, physicochemical and clinical validation for the use of potassium citrate in the treatment of hypocitraturic calcium nephrolithiasis and uric acid lithiasis with or without calcium nephrolithiasis.

Adult↗