Biomedical subjects

L Eales

Publications and source records attributed to L Eales.

At least 55 records · Page 3Linked to original sources

PubMed1976

Hepatic haem metabolism in porphyria cutanea tarda (PCT): enzymatic studies and their relation to liver ultrastructure.

Hepatic levels of cytochrome P-450 are elevated more than 4-fold in porphyria cutanea tarda (PCT) but not in other hepatic porphyrias or in non-porphyrics with alcoholic liver disease. In this study the ability of liver homogenates to metabolise aminopyrine and benzpyrene was correlated with hepatic cytochrome P-450 levels and with liver ultrastructure. The Km and Vmax for aminopyrine-N-demethylation and for benzpyrene hydroxylation exhibited a wide range of values with no significant differences between PCT patients and nonporphyric controls. Proliferation of the hepatic smooth endoplasmic reticulum in PCT was not significantly different from that observed in liver tissue obtained from patients with variegate porphyria or protoporphyria. Kushner reported data suggesting diminished uro'gen-I-decarboxylase activity as the autosomal dominantly inherited metabolic defect in PCT. Red cell uro'gen-I-decarboxylase activity was measured in 5 PCT males and 4 PCT females and activities were compared with 16 sex- and age-matched non-porphyric control patients. There was no significant difference in uro'gen-I-decarboxylase activity in the PCT and non-porphyric patients nor was there any significant difference relating to the sex of the patient. The role of iron in PCT was studied indirectly using the hexachlorobenzene porphyric rat as the rodent model.

Aminopyrine↗

PubMed1976

The hepatic lesion in protoporphyria (PP): preliminary studies of haem metabolism, liver structure and ultrastructure.

Five unrelated patients with protoporphyria (PP) had diagnostic liver biopsies performed to assess the degree of liver damage. The porphyrin content of the liver was quantitated and characterized and liver damage was assessed. Ultraviolet (UV) microscopy was performed in each case. Liver structure was assessed by light, polarization and electron microscopy. In 3 patients the liver was visualized directly before biopsy through a peritoneoscope. Liver damage ranged from minimal cell necrosis to portal fibrosis; the latter was observed in a 27-year-old sib of a patient (M.I.) who had died, aged 29, 3 years previously in liver failure from PP-related cirrhosis. Liver tissue from the latter patient which was obtained at the time of autopsy was re-examined by light and polarization microscopy. Hepatic pigment deposits, thought to be lipofuscin, showed birefringence on polarization microscopy in two cases, one of them being patient M.I. with PP-cirrhosis. Liver fluorescence on UV microscopy was centrizonal, punctate, faded rapidly and was easily distinguishable from that seen in porphyria cutanea tarda (PCT). The porphyrin content of the liver tissue in biopsied patients was between 5 mug and 80 mug, and in the autopsy case 1600 mug protoporphyrin/g wet weight liver, and on thin layer chromatography only dicarboxylic porphyrins were demonstrable. Hepatic cytochrome P-450 levels in protoporphyria were within normal range. Vmax and Km for aminopyrine-N-demethylation and benzpyrene hydroxylation did not differ significantly from our findings in PCT, variegate porphyria in remission and in non-porphyric controls. However, the activity of hepatic delta-aminolaevulinic acid (ALA) synthetase was significantly enhanced in 2 of the 3 patients in whom this measurement was performed.

Adult↗

PubMed1975

Analgesic renal papillary necrosis.

Analgesic nephropathy is well recognised. This is a retrospective review of 19 patients with the disease, who presented at Groote Schuur Hospital over a 4-year period. The diagnosis was made on historical and clinical grounds and on the radiological manifestations of papillary necrosis. The mean age was 49 years (26 - 74) with a sex ratio of 3,8 female : 1 male. The period of abuse varied between 3 and 20 years. Aspirin, phenacetin, codeine, and antipyrine were the compounds mainly ingested. If the abuse is stopped, renal deterioration can be halted. However, factors which lead to dehydration and infection tend to cause further decompensation. As a means of preventing this disease greater control over analgescis is needed.

Adult↗

PubMed1975