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Biomedical subjects

C J White

Publications and source records attributed to C J White.

At least 127 records · Page 7Linked to original sources
PubMed1988

Chronic granulomatous disease of childhood. An unusual case of infection with Aspergillus nidulans var. echinulatus.

Aspergillus nidulans var. echinulatus was the sole agent cultured from the left lung, a paraspinal abscess, left ribs, and thoracic vertebral bodies from a patient with chronic granulomatous disease. Hyphal elements were present in histologic sections of lung, vertebral bodies, and infected ribs along with granuloma formation. The patient was treated with two debridement procedures and insertion of a Harrington rod followed by a long course of amphotericin B, flucytosine, and daily white blood cell transfusions.

Abscess↗
PubMed1987

Hormonal and renal responses to converting enzyme inhibition during maximal exercise.

The role of angiotensin II in the hormonal and renal responses to maximal exercise was investigated by using the angiotensin-converting enzyme inhibitor captopril. Nine male subjects performed a standardized maximal treadmill test with and without acute captopril treatment (25 mg orally). At rest, captopril elevated plasma renin activity and lowered aldosterone levels. With maximal exercise, captopril treatment reduced the increase in mean arterial blood pressure by 8 mmHg and the increase in plasma renin activity by 3.0 ng ANG I.ml-1.h-1. The responses of adrenocorticotropin (ACTH), cortisol, and vasopressin to maximal exercise were not altered by captopril treatment. Although aldosterone levels were reduced at rest with captopril, during maximal exercise no difference was noted between treatments. Captopril treatment had no effects on the renal handling of salts or water during exercise. In conclusion, angiotensin II plays a role in the increase in mean blood pressure during maximal exercise in normal subjects but has no effect on the exercise responses of ACTH, vasopressin, and aldosterone or on the renal handling of salts and water.

Adrenocorticotropic Hormone↗
PubMed1986

Objective benefit of nifedipine in the treatment of Raynaud's phenomenon. Double-blind controlled study.

To compare the effects of the calcium channel antagonist, nifedipine, with that of placebo, a randomized double-blind crossover study was performed in 11 patients with moderate to severe Raynaud's phenomenon. Digital skin temperature recovery time was measured after immersing the patient's hand in ice water for 20 seconds. Patients were randomly assigned to receiving either nifedipine or placebo for one week, followed by the crossover phase. Skin temperature recovery time was also measured in 21 normal volunteers. The mean time to recovery for patients taking nifedipine was 28.5 +/- 20.8 minutes versus 44.9 +/- 18.9 minutes for patients receiving placebo (p less than 0.05 by analysis of variance with repeated measures). The mean time to recovery for the normal volunteers was 11.3 +/- 7.2 minutes versus 40.2 +/- 19.9 minutes for the patients (p less than 0.01 by the Student t test). Nine of the 11 patients noted improvement of symptoms during treatment with nifedipine. It is concluded that nifedipine is an effective, well-tolerated treatment for Raynaud's phenomenon.

Adult↗
PubMed1986

Phagocyte defects.

Although inherited forms of phagocyte defects affect a small proportion of the general population, their clinical course can be altered dramatically by a physician's awareness of these diseases and modifications of the approach to and treatment of affected patients. The most common syndromes are chronic granulomatous disease of childhood (CGD), the Chediak-Higashi syndrome (CHS), the hyperimmunoglobulin-E-recurrent infection (Job's) syndrome (HIE), and myeloperoxidase (MPO) deficiency. CGD patients have defects in the oxidative metabolism involved in killing catalase-positive organisms. CHS patients have giant granules defective in fusing with phagosomes and subsequent killing of ingested organisms. HIE patients have abnormal chemotaxis and elevated IgE levels and are susceptible to skin infections with Staphylococcus aureus and recurrent sinopulmonary infections. MPO-deficient patients often go undetected since they rarely have recurrent infections unless they have a concomitant disease such as diabetes mellitus. Patients with a recently described syndrome, C3bi receptor deficiency, have recurrent bacterial infections and persistent leukocytosis, and their neutrophils have abnormal adherence and phagocytosis. The absence of specific granules is a more rare entity but these patients also have recurrent infections thought to be secondary to a chemotactic defect and a minor abnormality of microbial killing exhibited by their neutrophils. This review will focus on the clinical presentation and management of these patients.

Chediak-Higashi Syndrome↗
PubMed1986

Changes in the structural and functional properties of human eosinophils during experimental hookworm infection.

Normal volunteers were infected with hookworm larvae Necator americanus. Peripheral blood counts showed a mean of 524 +/- 29 eosinophils/mm3 of blood before infection and a mean of 3,008 +/- 456 eosinophils/mm3 of blood during infection (P less than .01). Absolute numbers of neutrophils did not change. Eosinophils and neutrophils from the infected period were compared with the noninfected state in each subject. The percentage of hypodense eosinophils increased from a mean of 34% +/- 13% to 80% +/- 7% during infection (P less than .05). Superoxide production of eosinophils increased from a mean of 56 +/- 9 to 97 +/- 12 nmol of O2-./10(6) cells per 60 min (P less than .05) during infection. Chemotaxis of eosinophils to Escherichia coli endotoxin-activated serum increased from a mean average distance migrated of 19 +/- 2 micron (P less than .05), whereas neutrophil responsiveness did not change. This is the first report of changes in eosinophil density and stimulation of eosinophil function in normal hosts experimentally infected with hookworm. The data indicate that hookworm infection preferentially increases eosinophil production and activity with little effect on neutrophils.

Chemotaxis, Leukocyte↗
PubMed1983

Increased left ventricular ejection fraction after a meal: potential source of error in performance of radionuclide angiography.

The effect of a standardized meal on left ventricular (LV) ejection fraction (EF) was determined by equilibrium radionuclide angiography in 16 patients with stable congestive heart failure but without pulmonary or valvular heart disease. LVEF was determined in the fasting state and 15, 30, and 45 minutes after a meal. Patients with moderately depressed fasting LVEF (30 to 50%), Group I, had a mean increase of 6.9 +/- 2.9% (p less than 0.005) in the LVEF at 45 minutes after the meal. Patients with severely depressed fasting LVEF (less than 30%), Group II, had no change after the meal. It is concluded that significant increases in LVEF may occur after meals in patients with moderate but not severe left ventricular dysfunction. Equilibrium radionuclide angiography studies that are not standardized for patients' mealtimes may introduce an important unmeasured variable that will affect the validity of data in serial studies of left ventricular function.

Adult↗
PubMed1981

The incorporation in vitro of sulphate ions into synaptic-membrane glycoproteins.

Synaptosomes from sheep brain cortex were incubated with carrier-free Na235SO4 and the synaptic plasma membranes were isolated. The membranes were free of contamination from cytosol, mitochondria and microsomal material and accounted for 30% of the radioactivity present in the synaptosomal particulate fraction. Control experiments demonstrated that the radioactivity present in the preparation was not due to non-specific binding of sulphate ions. The synaptic membranes contained at least six 35S-containing protein bands with molecular weights between 160 000 and 16 000. Analysis showed that the radioactivity was located in the carbohydrate moiety of a glycopeptide.

Animals↗
PubMed1981

Fucose incorporation and identification of fucosylglycoproteins in synaptosomes.

A synaptosome-enriched fraction from sheep cortex was incubated with L-fucose. The uptake of the sugar into this preparation was dependent on time, temperature, and concentration. A Kmapp of 0.94 mM-L-fucose and a Vmaxapp value of 0.24 nM-L-fucose/mg synaptosomal soluble protein/20 min was determined. After incubation for 10 min at 25 degrees C with L-[3H]fucose, 70% of the radioactive label was found in the soluble fraction. DEAE-cellulose chromatography resulted in the elution of three fucosylprotein peaks which were then characterised by gel filtration and sodium dodecyl sulfate-polyacrylamide electrophoresis (SDS-PAGE). At least eleven 3H protein-staining bands were identified with M. W. 13,000--115,000. Control experiments involving the incubation of the hexose with heat-treated synaptosomes and myelin, mitochondria, and microsomes indicted that the tritiated material associated with the synaptosomal soluble fraction was not due to nonspecific binding or to the presence of contaminating subcellular material. A 3H glycopeptide was identified, and on analysis the carbohydrate moiety was found to be rich in sialic acid, fucose, galactose, mannose, and N-acetylglucosamine. Mild acid treatment of the glycopeptide released fucose, which implies that this carbohydrate occupies a terminal position in the oligosaccharide chain. From these results it is proposed that synthesis or the modification of soluble fucosylglycoproteins is possible in synaptosomes.

Amino Acids↗
PubMed1979

The influence of pre- and perinatal malnutrition on sulphated glycosaminoglycans in rat brain.

Pre- and perinatal malnutrition of rats was achieved by restricting the intake of food to 50% during lactation and pregnancy. After 40 days offspring were injected with Na2(35)SO4 before being killed. Lipid-free brain material was now hydrolysed with papain and glycosaminoglycan samples chromatographed on DEAE-cellulose. After chemical characterisation studies 2.5 times more chondroitin sulphate was detected in tissue from the ill-fed animals. Little variation in heparan sulphate content was observed. The marked increase in the concentration as well as qualitative changes in sulphated glycosaminoglycans during pre- and perinatal malnutrition as compared to the normal are discussed in relation to brain maturation.

Animals↗
PubMed1979

Identification of glycosaminoglycans in nerve terminals.

Synaptosomes were prepared using sucrose and Ficoll density-gradient-centrifugation procedures. Extraction of lipid-free material from both preparations with guanidinium chloride together with papain treatment released hexuronic-containing fractions. The glycosaminoglycan fractions (C1, C2, and C3) were isolated after ion-exchange chromatography. Chemical studies identified fraction C1 as a chondroitin sulphate proteoglycan whereas fractions C2 and C3 were characterised as hyaluronic acid and heparan sulphate. The relative yields of glycosaminoglycans (as compared with brain mitochondria) strongly suggest that these macromolecules form an integral component of nerve endings. The possible role of glycosaminoglycans in synaptosomes is also discussed.

Animals↗