Search PubMed⌕ Search

Biomedical subjects

J Sheehan

Publications and source records attributed to J Sheehan.

At least 91 records · Page 5Linked to original sources

Diuretic-associated hypomagnesaemia.

Clinically suspected hypomagnesaemia was confirmed in 21 patients over 12 months; all patients had been exposed to either short-term vigorous diuretic treatment or moderate-dosage long-term treatment. Magnesium depletion was compounded by a hospital diet surprisingly low in magnesium, a local soft water supply, and, in some patients, high alcohol intake. Common presenting symptoms included depression, muscle weakness, refractory hypokalaemia, and atrial fibrillation refractory to digoxin treatment. The administration of magnesium supplements resulted in prompt improvement of all symptoms particularly in the case of refractory atrial fibrillation. Chronic low-grade magnesium deficiency from diuretic treatment is more common than published reports suggest. Older patients are at risk, particularly those who have excessive alcohol intake, a diet low in magnesium, or a soft water supply.

Aged↗

Drugs and sperm.

Explore the source record for details and available documents.

Chloramphenicol↗

Self-association of dermatan sulphate proteoglycans from bovine sclera.

1. Two proteodermatan sulphate fractions (I and II) from bovine sclera were studied by gel chromatography, light-scattering and ultracentrifugation under various conditions. 2. Gel chromatography of proteoglycans in the absence or presence of hyaluronate was performed under associative conditions. No effect on the elution profile was noted. 3. Ultracentrifugation experiments (sedimentation-velocity and sedimentation-equilibrium) with proteoglycan I and II in 6 M-guanidine hydrochloride gave molecular weights (Mw) of 160000-220000 and 70000-100000 respectively. As the protein contents were 45% and 60% respectively, it may be calculated that proteoglycan I contained four to five side chains, whereas proteoglycan II contained one or two. Sedimentation-equilibrium runs performed in 0.15 M-NaCl gave an apparent molecular weight (Mw) of 500000-800000 for proteoglycan I and 90000-110000 for proteoglycan II. 4. In light-scattering experiments both proteoglycans I and II yielded high particle weights in 0.15 M-NaCl (3.1 X 10(6) and 3.4 X 10(6) daltons respectively). In the presence of 6 M-guanidine hydrochloride the molecular weights decreased to 410000 and 130000 respectively. The particle weights in 0.15 M-NaCl were not altered by the addition of hyaluronate or hyaluronate oligosaccharides. 5. The dermatan sulphate side chains of scleral proteoglycans (L-iduronate/D-glucuronate ratio 7:13) gave a particle weight of 100000 daltons in 0.15 M-NaCl. In 1.00 M-KCl/0.02M-EDTA the molecular weight was 24000. Addition of free scleral dermatan sulphate chains to a solution of proteoglycan II promoted further multimerization of the macromolecule.

Animals↗