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Biomedical subjects

J T McCall

Publications and source records attributed to J T McCall.

At least 37 records · Page 2Linked to original sources
PubMed1981

Zinc nutrition in Crohn's disease.

A prospective evaluation of zinc status was made in 63 randomly selected patients with Crohn's disease. In the patients, mean serum and 24-hr urinary zinc values--105 microgram/dl and 383 microgram/day, respectively--were not different from controls. However, 46% of these patients had less than normal serum zinc and 36% had low urinary zinc excretions. Simultaneous reductions in both serum and urinary zinc were detected in 19% of patients. A direct correlation (P = 0.01) was found between serum levels of zinc and the concentration of albumin, the major zinc-binding protein, in outpatients but not in hospitalized patients or patients with Crohn's disease as a whole. Intake of zinc was surprisingly good--a mean intake of 13.4 +/- 1.4 mg/day. A significant (P = 0.006) association was found between urinary zinc and the Crohn's disease activity index but not between serum zinc concentration and this index. No association was found between zinc measurements and the presence or absence of fistulas, use of prednisone or sulfasalazine (Azulfidine), large bowel resections, and length of small bowel resected.

Adult↗
PubMed1981

Effect of stimulus on the chemical composition of human tears.

We examined the effect of the nature of the stimulus on the chemical composition of human tears. The protein concentration of emotional tears from women exceeded that of irritant-induced tears by 24% (P less than .01). Polyacrylamide disk gel electrophoresis disclosed no significant difference between the distribution of positively or negatively charged proteins of irritant-induced and emotional tears. Manganese concentrations in tears (30 ng/ml) exceeded serum concentrations from the same subjects by 30-fold. These manganese concentrations in tears were considerably less than previously reported values. We found no differences for the concentrations of protein or manganese in human tears between the sexes.

Adolescent↗
PubMed1980

Hemodialysis encephalopathy with osteomalacic fractures and muscle weakness.

The hemodialysis unit at Columbia, South Carolina, opened in April, 1974. By June of 1977, 7 patients had died from dialysis encephalopathy, and 16 of the 51 surviving patients showed speech disorders, fits, and myoclonic jerks. Pathologic fractures were seen in 22 patients. Bone histomorphometry showed severe osteomalacia with minimal, if any, osteitis fibrosa, and serum alkaline phosphatase activity was normal. The mean serum aluminum concentration in 33 random patients was elevated at 83.5 microgram/liter (control group, 13.9 microgram/liter, P less than 0.001). The mean bone aluminum concentration in 4 patients who died from this syndrome was 307 ppm of bone ash (normal, less than 10 ppm). Dialysis fluid aluminum was high at 140 microgram/liter. Purification of the dialysis fluid with a water softener, reverse osmosis and a deionizer and abandoning extra-strength Basaljel resulted in a notable clinical and EEG improvement. None of 81 new patients who started hemodialysis between July of 1977 and July of 1979 after the change in treatment have developed any such symptoms. A syndrome of hemodialysis encephalopathy accompanied by pathologic osteomalacic fractures is described. Recovery is possible. The syndrome was eradicated after purification of the dialysis fluid.

Aged↗
PubMed1980

Recovery of dietary iron and zinc from the proximal intestine of healthy man: studies of different meals and supplements.

The technique of marker perfusion of the upper gastrointestinal tract was used to measure intraluminal quantities of iron and zinc after test meals in healthy humans. Two different meals, one based on hamburger (with a predominance of heme iron, 7.5 mg/meal) and one based on cereal (containing inorganic iron; 1.4, 5.3, or 4.6 mg), were used. In addition, the luminal behavior of ferrous sulfate and hydrogen-reduced metallic iron (used as supplements to the cereal meal) were compared. Different meals also contained low (2.4 mg) or high (5.5 mg) amounts of zinc. The intubation techique allowed disappearance of metals from the duodenum and jejunum to be compared. The patterns of luminal flow were different for iron and zinc. Whereas iron was never recovered from the lumen at levels above those ingested in meals, zinc was recovered from the duodenum at levels greater than those ingested. These findings suggest that zinc, but little iron, is added to chyme in the upper gut during digesting and absorption. Bioavailability of different forms of iron, as judged by their luminal disappearance, were similar. Inorganic iron, ferrous sulfate, and hydrogen-reduced metallic iron were absorbed about as effectively as was heme iron. Iron disappeared preferentially from the duodenum but the site of zinc absorption appeared to be more distal.

Adult↗
PubMed1980

The endoneurial content of lead related to the onset and severity of segmental demyelination.

The endoneurial lead and water content was serially evaluated in the nerves of rats fed lead carbonate and related to the onset and severity of segmental demyelination and remyelination. Lead began to accumulate significantly in the endoneurium by 5 days, reached a maximum level (71 microgram/g dry weight) by 34 days, and then fell to the perineurial level (28 microgram/g dry weight) by 3 months. The water content of endoneurium did not become significantly increased until the 50th day. Extensive teased fiber grading of pathologic abnormalities carried out on the same animals showed that segmental demyelination began between the 20th and 35th days and worsened progressively. This provides the first evidence that high endoneurial lead concentration precedes segmental demyelination and nerve edema. It suggests that the random Schwann cell damage is more likely to be due to a direct toxic effect of lead rather than to a factor associated with edema or increased endoneurial pressure. Contrary to our expectations, lead content does not parallel water content, as would be expected if lead entry into the endoneurium were associated with an abrupt breakdown of the blood-nerve barrier. A further new finding is the decrease in endoneurial lead content at a time when edema and the pathologic lesions are progressing. This may suggest the development of lead removal mechanisms.

Animals↗
PubMed1980

Hemostasis in the copper-laden Bedlington terrier: a possible model of Wilson's disease.

A hemostatic survey was done on 14 Bedlington terriers, 13 of which have the recently discovered copper toxicosis. Their hepatic copper ranged from 109 to 9,888 microgram/g dry weight and their ages from 8 months to 8 years. Despite histologic evidence of hepatitis in younger dogs and cirrhosis in older ones, plasmatic coagulation factors were not depressed. In fact, the hemophilic factors VIII, IX and XI were above normal, more closely related to the age of the dog than to the hepatic copper. Furthermore, their platelet were unusually sensitive to adenosine diphosphate exposure. Offsprings of matings between Bedlington terriers and Beagles seem to be normal.

Animals↗
PubMed1979

Fate of oral neutralizing antacid and its effect on postprandial gastric secretion and emptying.

The fate and neutralizing efficiency of oral antacids (aluminum and magnesium hydroxides) as well as their effect on postprandial gastric function were quantified in 6 patients with duodenal ulcer disease. We employed a double-marker technique for measurement of gastric secretion and emptying and combined this with back-titration of the gastric samples and analysis of aluminum to trace the fate of antacid in the stomach and duodenum. These studies show that: (a) antacid therapy with aluminum and magnesium hydroxides significantly increases gastric secretion; (b) intragastric neutralization of gastric acid produces a significant and substantial decrease in net acid output (acid secreted minus acid neutralized), but the beneficial effects of neutralization are partially offset by incomplete intragastric formation of aluminum trichloride; (c) most but not all of the ingested antacid is utilized in acid neutralization in the stomach (average 78.6% in our 6 patients); and (d) antacid therapy does not modify the absolute rate of postprandial gastric emptying, but increases dilution of gastric contents, expanding the intragastric volume. Thus, the fractional gastric emptying rate declines, and this, in turn, should enhance antacid utilization by delaying its emptying.

Administration, Oral↗
PubMed1979

Copper stains and the syndrome of primary biliary cirrhosis. Evaluation of staining methods and their usefulness for diagnosis and trials of penicillamine treatment.

Use of Shikata's stain was found to be a sensitive method for the demonstration of copper-protein complexes, but use of the rhodamine stain may be more reliable. Interobserver agreement was slightly better with Shikata's stain. Hepatic copper increased with the histologic progression of chronic nonsuppurative destructive cholangitis (CNDC). All specimens that contained Mallory bodies and most specimens (91%) that contained bile yielded positive copper stains. No correlation was found between positive copper stains and other histologic features. A strongly positive copper stain aided in the diagnosis of CNDC. All specimens with negative copper stains contained less than 250 microgram of copper per gram of dry weight. From a strongly positive copper stain, the chemical copper content could not be predicted with certainty. Shikata's method seemed adequate to evaluate penicillamine treatment trials.

Adult↗
PubMed1978

Pancreatic, gallbladder, and intestinal responses to intraluminal magnesium salts in man.

To assess the effects of magnesium chloride or magnesium sulfate on the release of cholecystokinin from the duodenum, outputs of trypsin and bilirubin were quantified during perfusion of the duodenum with isotonic solutions of these salts. Net intestinal water transport was also quantified. The results suggest that magnesium ion in the duodenum is a relatively weak stimulus to the pancreas and gallbladder, an action not augmented by the concomitant presence of the sulfate ion. As determined by this human bioassay method, magnesium is a weak stimulant to cholecystokinin release. Furthermore, magnesium chloride inhibits net jejunal water absorption and magnesium sulfate is even more potent, promoting net water secretion, effects which cannot be entirely attributed to cholecystokinin release.

Adult↗
PubMed1978

Effect of cation content of agar on the activity of gentamicin, tobramycin, and amikacin against Pseudomonas aeruginosa.

Fifty-five strains of Pseudomonas aeruginosa were tested against arithmetic increments in concentrations of gentamicin, tobramycin, and amikacin in 14 different lots of Mueller-Hinton agar. The divalent cation content of each lot was determined by atomic absorption spectrometry. The relation between mean minimal inhibitory concentration (MIC) for strains within each lot and cation content was studied by stepwise regression. Among the cations, the content of Zn++ most highly correlated with the MIC of each aminoglycoside; however, Zn++ accounted for only 23%, 60%, and 47% of the variability in the mean MIC of gentamicin, tobramycin, and amikacin, respectively, against all strains. In two-cation models Zn++ with Ca++ or Cu++ was most highly correlated with the mean MICs of the three aminoglycosides against all strains. No divalent cation, either singly or in combination with one or two other cations, gave a good prediction of the MICs of the aminoglycosides in agar. Furthermore, there was variability in the cations that most highly correlated with the MICs for some strains. These observations support the concept that ionic strength, cations, and a variety of other as yet poorly defined components of media influence the activity of aminoglycosides against P. aeruginosa.

Agar↗
PubMed1977

Theophylline concentrations in asthmatic patients after administration of aminophylline.

To test the efficacy of using a weight-derived formula to determine aminophylline dosages, 50 patients hospitalized for treatment of severe asthma were given intravenous aminophylline infusions at a rate of 0.9 mg/kg/hr to a maximum dosage of 1,500 mg/24 hr. Serum theophylline determinations done 12 to 96 hours after institution of this therapy showed levels greater than 20 mg/liter in 34% of these patients. Reliance on weight-derived formulas can be dangerous.

Adolescent↗
PubMed1977

Pigmented corneal rings in non-Wilsonian liver disease.

Kayser-Fleischer rings are pigmented corneal rings at the limbus of the cornea in Descemet's membrane that have been deemed pathognomonic of Wilson's disease. However, we have observed four exceptions in patients with non-Wilsonian liver disease. Three patients had primary biliary cirrhosis and one patient had chronic aggressive hepatitis with cirrhosis. Pigmented corneal rings were seen only by slit-lamp examination. Hepatic, serum, and urinary copper and serum ceruloplasmin levels were significantly elevated in the patients with primary biliary cirrhosis. Radiocopper (64Cu or 67Cu) studies in patients with primary biliary cirrhosis showed plasma disappearance curves which allowed a clear distinction from Wilson's disease in that all three patients with primary biliary cirrhosis showed a secondary rise in radiocopper that presumably represented copper incorporation into ceruloplasmin. In one patient, in whom 64Cu in ceruloplasmin was studied specifically, incorporation was found to be normal.

Ceruloplasmin↗
PubMed1977

Effect of D-penicillamine on copper retention in patients with primary billiary cirrhosis.

As part of a double blind, randomized trial evaluating D-penicillamine in primary biliary cirrhosis, we monitored urinary copper excretion and hepatic copper concentration during the 1st year of therapy in 46 patients with this disease. The retention of copper in primary biliary cirrhosis was confirmed by finding abnormally high levels of standard copper measurements in almost all patients before treatment. The hepatic copper was elevated in 43 of 45 patients, the urinary copper in 42 of 46, and the ceruloplasmin in 46 of 46. Urinary copper excretion correlated with the hepatic copper concentration (r = 0.68, P less than or equal to 0.001). No significant correlation occurred between hepatic copper and ceruloplasmin. Hepatic copper concentrations greater than 400 microng per g of dry weight were found almost exclusively in patients with advanced histological disease (P less than or equal to 0.01). Therapy with D-penicillamine and a low copper diet sustained increased urinary copper excretion for 1 year in almost all patients (P less than or equal to 0.001). Among patients taking placebo, the median hepatic copper concentration increased 13 microng per g of dry weight after 1 year. In contrast, among the patients taking D-penicillamine, the median hepatic copper concentration decreased 99 microng per g of dry weight (P less than or equal to 0.02). Continued observation of this therapeutic trial may help to clarify the relationship of copper retention and liver injury in primary biliary cirrhosis.

Ceruloplasmin↗
PubMed1977

Biliary secretion of copper in healthy man. Quantitation by an intestinal perfusion technique.

A duodenal perfusion technique which permitted a normal daytime eating pattern of three liquid meals and an overnight fast was used to measure the 24-hr output of copper in bile in 19 studies in 14 persons with normal hepatic and gallbladder function. Daily biliary output was also determined by direct measurement on four 24-hr bile collections obtained from 3 patients with complete biliary diversion, and in 4 patients measurements of dietary copper intake and fecal copper output were also made. A mean bile copper output of 25 +/- 13 microng per kg-day (1.7 mg +/- 0.8) (mean +/- SD) was obtained in 19 perfusion studies; the range was 9.0 to 53.0 microng per kg-day. The values in the 24-hr bile collections were similiar to those obtained using the perfusion method. Biliary copper output was similar during the day and night, and there was no correlation between hourly rates of copper output and hourly rates of bile acid output, nor was there any correlation between daily copper output and daily bile acid output. The similar values for dietary intake, biliary output, and fecal output provide additional support for the current view that in healthy man copper balance is maintained by biliary secretion and subsequent fecal excretion of copper which has been absorbed in the stomach and proximal duodenum.

Bile↗
PubMed1976

Acquired zinc deficiency. Cutaneous manifestations typical of acrodermatitis enteropathica.

A patient given long-term total parenteral nutrition acquired a zinc deficiency severe enough to cause typical cutaneous manifestations of acrodermatitis enteropathica. This report, the first detailed one, to our knowledge, of such an association, adds to the accumulating evidence that supplementation of trace elements is needed in long-term parenteral nutrition.

Acrodermatitis↗
PubMed1976

Abnormalities of chemical tests for copper metabolism in chronic active liver disease: differentiation from Wilson's disease.

Because identical clinical findings, alterations of hepatic function, and changes in hepatic morphology can occur in Wilson's disease (WD) and chronic active liver disease (CALD), chemical tests that reflect copper metabolism are important in the differential diagnosis of these conditions. The authors therefore measured 24-hr urinary copper excretion, hepatic copper concentration, and serum ceruloplasmin concentration in 54 patients with CALD. Twenty-four hour urinary copper excretion was increased in about 50% of patients, was significantly higher during active disease compared to remission, and was in the WD range in approximately 10% of patients. Hepatic copper concentration was also increased in the majority of patients, generally during active disease, and it sometimes overlapped with values reported in WD. By contrast, serum ceruloplasmin levels were elevated in nearly one-half the Cald patients and were never below normal. It is concluded that the chemical tests routinely used to assess copper metabolism in WD are frequently abnormal in CALD. Because the serum ceruloplasmin concentration never fell in the WD range and often was elevated, it is the most reliable routine chemical screening test to differentiate between CALD and WD.

Adolescent↗