PubMed Health⌕ Search

Biomedical subjects

M Austin

Publications and source records attributed to M Austin.

8 recordsLinked to original sources
PubMed1979

Isolation of a virus from the pancreas of a child with diabetic ketoacidosis.

A healthy 10-year-old boy was admitted to the hospital in diabetic ketoacidosis within three days of onset of symptoms of a flu-like illness. He died seven days later and post-mortem examination showed lymphocytic infiltration of the islets of Langerhans and necrosis of beta cells. Inoculation of mouse, monkey and human cell cultures with homogenates from the patient's pancreas led to isolation of a virus. Serologic studies revealed a rise in the titer of neutralizing antibody to this virus from less than 4 on the second hospital day to 32 on the day of death. Neutralization data showed that the virus was related to a diabetogenic variant derived from Coxsackievirus B4. Inoculation of mice with the human isolate produced hyperglycemia, inflammatory cells in the islets of Langerhans and beta-cell necrosis. Staining of mouse pancreatic sections with fluorescein-labeled antiviral antibody revealed viral antigens in beta cells. Both the clinical picture and animal studies suggested that the patient's diabetes was virus induced.

Animals↗
PubMed1979

Heart disease risk factors and hormone use in postmenopausal women.

A population of 1,496 women aged 55 to 74 years was studied for the distribution of heart disease risk factors in the presence or absence of postmenopausal estrogens. Current hormone use was reported by 39%. Hormone users were significantly slimmer than nonusers at all ages. After adjustment for the effect of obesity, hormone users had significantly lower mean levels of plasma cholesterol and higher mean levels of plasma triglycerides than nonusers. Blood pressure and fasting plasma glucose concentration tended to be lower among hormone users, although the differences were not statistically significant in all age groups. This article discusses the theoretical implications of these observations for cardiovascular disease mortality and contrasts them with the cancer risk of postmenopausal estrogen use.

Age Factors↗
PubMed1978

Differences between respondents and non-respondents in a population-based cardiovascular disease study.

The differences in cardiovascular health status between participants and non-participants were examined in a population-based cardiovascular study. Telephone interviews with non-respondents revealed generally more cardiovascular disease but less hyperlipidemia and family history of cardiovascular disease. Non-respondents did not differ regarding known hypertension, diet or drug therapy for hyperlipidemia, or egg use. Non-respondents were more likely to be cigarette smokers. Because the amount of non-respondent bias in the study was small while the response rate was high, respondents were generally representative of the target population. However, the observed differences could have produced spuriously high estimates of risk factor prevalence, low estimates of disease prevalence, and biased relative risks if the non-response rate and/or the baseline differences had been considerably larger.

Adult↗
PubMed1975

Human islet cell adenoma: metabolic analysis of the patient and of tumor cells in monolayer culture.

Cell cultures were established from a benign pancreatic islet adenoma. Over 200 muU/culture/day immunoreactive insulin were found in culture media. Cultures with medium 199 released insulin for about 2 months; those with medium F12K were maintained for over 7 months, and have been successfully subcultured. Increasing culture medium glucose to 326 mg per 100 ml, alone or with leucine (10 mM) or theophylline (2 mM), failed to increase insulin release above baseline. Studies in the patient prior to surgery using oral glucose, leucine, beef meal, intravenous tolbutamide, and glucagon failed to increase plasma insulin and thus were consistent with cell culture responses. Extracts of tumor tissue contained 23% proinsulin-like material; high insulin containing samples of culture medium had 5% proinsulin and less than 40 pg glucagon/ml. Aldehyde fuchsin positive granulation was sparse in both cultured cells and the original tumor. These studies demonstrate long term viability, in monolayer culture, of cells derived from this islet cell adenoma, with retention of secretory characteristics consistent with data obtained prior to removal of the adenoma from the patient.

Adenoma, Islet Cell↗
PubMedDate not supplied

The influence of the intrinsic sympathomimetic activity of beta-adrenoceptor antagonists on haemodynamic effects in anaesthetized dogs.

1. The effects of propranolol, atenolol (ICI 66,082), practolol and pindolol on heart rate and maximal left ventricular dp/dt, atrioventricular conduction time, mean aortic flow and diastolic blood pressure during cardiac pacing were investigated over a wide dose range (0.025-4.0 mg/kg, i.v.) in dogs anaesthetized with pentobarbitone.2. Propranolol and atenolol produced similar reductions in haemodynamic parameters. Propranolol had no further effect in dogs pretreated with atenolol. 3. Practolol tended to cause smaller reductions in the haemodynamic parameters than either propranolol or atenolol. Subsequent administration of propranolol still had some depressant activity. 4. Pindolol produced a biphasic response, with depression of cardiac function at the low doses (0.025 and 0.1 mg/kg), but a reversal of effect as the dose was increased. 5. It is therefore concluded that, in anaesthetized dogs, the intrinsic activity of practolol and pindolol limits the fall in heart rate, cardiac conduction, aortic flow and maximal dp/dt observed with beta-adrenoceptor blockade. With pindolol, however, the influence of intrinsic activity is observed only in high doses related to beta-adrenoceptor blockade.

Adrenergic beta-Antagonists↗