Biomedical subjects

G Petereit

Publications and source records attributed to G Petereit.

3 recordsLinked to original sources

PubMed2002

Influence of clinical factors, diet, and drugs on the human upper gastrointestinal glutathione system.

BACKGROUND: Glutathione (GSH) and the cytosolic glutathione S-transferases (GSTs) protect the gastrointestinal mucosa against the toxic effects of a wide variety of compounds, such as reactive oxygen species and electrophiles. AIMS: We wished to investigate the distribution along the upper gastrointestinal mucosa and the influence of clinical variables on components of the GSH system to learn more about factors which control its cytoprotective properties. METHODS: Antral and duodenal biopsies of normal appearing mucosa were collected from 202 patients (104 males, 98 females; mean age 62 years) undergoing upper gastrointestinal endoscopy. GSH content was examined by high pressure liquid chromatography, GST enzyme activity by 1-chloro-, 2, 4-dinitrobenzene conjugation, and levels of the GST classes alpha, pi, and theta by western blot. RESULTS: GSH, GST enzyme activity, and GST alpha levels were significantly lower (p<0.001) in the antrum than in the duodenum (antrum v duodenum: GSH 23.0 (0.7) v 35.0 (1.0) nmol/mg protein; GST activity 626 (19) v 832 (22) nmol/mg protein/min; GST alpha 4.5 (0.5) v 20.0 (0.7) microg/mg protein) while GST pi content was significantly higher (p<0.001) in antral than in duodenal biopsies (16.5 (0.7) v 11.2 (0.5) microg/mg protein). Antral GSH and GST activities were markedly lower in males compared with females (p<0.01). Some drugs (cisapride, diuretics, cortisol, analgesics) increased GST pi and GST alpha content but cytostatic drugs suppressed duodenal GST activity. High intake (>3 days a week) of vegetables enhanced duodenal GST alpha and GST pi and high intake of fruits the antral content of GST theta 1. CONCLUSIONS: The gastrointestinal GSH system represents the antitoxic barrier of the mucosa; its activity is influenced by localisation, sex, and drugs, and its enzymes are stimulated by a high intake of vegetables and fruits.

Adolescent↗

PubMed1996

Digitoxin intoxication with lethal outcome.

A 65-year old woman with known history of reactive depression and failed suicide attempts ingested 7 mg digitoxin at 09.00 h. After vomiting 4 hours later, she reported the drug intake to her husband who thereupon summoned a physician. Arriving at 16.00 h, the physician was informed about the suicide attempt, but failed to initiate any specific measures. After a second doctor's visit at 22.00 h, the patient was rushed to hospital in a moribund state. In spite of a gastric lavage, treatment with activated charcoal and insertion of a transvenous pacemaker, the patient died at 23.45 h with signs of total atrioventricular block. Digitalis fab fragments could not be administered in time. A calculation based on the plasma digitoxin concentration of 212 ng.ml-1 measured at 23.00 h indicated that nearly the entire ingested dose had been absorbed. Thus, neither the vomiting nor the gastric lavage eliminated significant amounts of the drug which had left the stomach without delay. Under these circumstances, the failure to initiate timely therapy with specific digitalis fab fragments ultimately contributed to the lethal outcome.

Aged↗

PubMed1994

[Reversible thrombocytopenia due to digitoxin overdose].

A 65-year-old woman, known to have peptic ulcers, developed nausea and retching. Clinical examination demonstrated pain on pressure in the epigastrium with otherwise normative findings for age. Two gastric ulcers and gastritis with erosions were seen at endoscopy. The patient, who was being treated with digitoxin for heart failure, reported having taken up to four digitoxin tablets (0.07 mg each) daily because she had insomnia. The plasma digitoxin level was between 150 and 160 nmol/l (therapeutic range 17-33 nmol/l), while the ECG showed no signs of digitalis intoxication. Initially the platelet count was 40,000/microliter: there had been no history of thrombocytopenia or symptoms of abnormal haemostasis. Other laboratory tests were within normal limits. After digitoxin had been discontinued, the platelet count rose without further treatment to 373,000/microliter 3 weeks after hospital admission by which time the digitoxin level had fallen to 48.9 nmol/l. The gastrointestinal symptoms regressed completely on treatment with omeprazole (40 mg three times daily for 8 days) and ranitidine (150 mg twice daily).

Aged↗