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Biomedical subjects

G Bianchi

Publications and source records attributed to G Bianchi.

At least 487 records · Page 27Linked to original sources
PubMed1979

Bioavailability and related heart function index of digoxin capsules and tablets in cardiac patients.

A loading dose of digoxin (750 microgram) in two commercial formulations was administered to 14 patients with heart disease according to a crossover design. One formulation consisted of soft gelatin capsules containing a solution of digoxin; the other formulation was compressed tablets. All parameters investigated, i.e., serum peak height, time of the peak, area under the serum level--time curve (AUC), and area above the Q--S2I (electromechanical systole) decrease (obtained from polycardiographic evaluation), showed better bioavailability of digoxin capsules than tablets, averaging 36.3%. The better bioavailability of digoxin capsules than tablets seems to be more evident in heart disease patients than that encountered previously in healthy subjects. The AUC and the area above the Q-S2I decrease were linearly correlated only with digoxin capsules.

Adult↗
PubMed1979

A method for the in situ measurement of the electrical quantities in frog skin.

A method allowing the measurement of the electrical quantities related to the physiological functions of the frog skin in situ is presented. The method allows the performance of several experiments on the same pithed animal, which remains alive for a number of days. The preparation is very stable, and the electrical potential difference and short-circuit current values are higher than in isolated skin. The theory of measurement and the possible systematic errors are discussed. The possibilities of the method are evaluated on comparing the pH and temperature dependence of the electrical quantities in situ with previous measurements on isolated skin.

Animals↗
PubMed1979

Alternation of partial and total atrial standstill.

A forty-five year old man with longstanding rheumatic heart disease whose surface electrocardiogram (ECG) showed absent P waves and two alternating QRS complex rhythms, one regular and the other irregular, was submitted to electrophysiological studies. For regular QRS complex rhythm these studies revealed (1) presence of total and bilateral atrial standstill and (2) regular ventricular rhythm originating in the A-V junction; while for irregular QRS complex rhythm the studies showed (1) presence of atrial standstill in the area of the upper right atrium, and (2) a +/- 150/min atrial activity rate in the intracavitary and esophageal electrogram and a +/- 300/min rate in the epicardial mapping. The spread of conduction of this atrial activity indicates that it originated within an atrial area near the tricuspid valve. The presence of an alternating partial and total atrial standstill is a unique feature which to data has not been reported in the literature.

Action Potentials↗
PubMed1979

Comparison of five different stress testing methods in the ECG diagnosis of coronary artery disease. Correlation with coronary arteriography.

Five different stress testing methods: bicycle ergometer exercise (BE), treadmill exercise (TD), isoproterenol infusion test (IPN), dopamine infusion test (DPM), and atrial pacing (AP), were performed on 90 male patients who underwent coronary arteriography. Ischemic S-T segment depression of 1.0 mm or greater was used as the criterion for a positive test. Within the group of 56 subjects having significant coronary artery disease (CAD) the diagnostic sensitivity of the single tests was as follows: 64.3% for BE, 66.1% for TD, 69.6% for IPN, 41.1% for DPM, 75.0% for AP. For the 34 subjects with no CAD the folowing specificity was found: 88.2% for BE and for TD, 82.3% for IPN, 85.3% for DPM, 63.8% for AP. When the results of the different tests were combined, it was seen that the association of an ergometric test with IPN enhanced the sensitivity of the exercise test (p less than 0.05) without significantly decreasing the specificity.

Adult↗
PubMed1978

Psychiatric antecedents of myocardial infarction.

Forty consecutive survivors after myocardial infarction (MI) were compared by means of a semistructured interview with a matched sample of 40 controls in respect of various psychosocial factors. The MI group reported a much higher prior occurrence of symptoms of anxiety and depression. The complaints included being tired, irritable, restless, upset and anxious, plus insomnia and anhedonia. Preceding stressful life events were about 2 1/2 times as common with the MI group. However, long-term persanality traits which were not recent additions due to psychiatric change before MI did not strongly discriminate between the two groups, and recognized variables such as cigarette smoking had a lesser association with MI. Similar results were obtained when information about each patient and each control was supplied by a close informant.

Adult↗
PubMed1978

Glossy mutants of maize. VIII. Accumulation of fatty aldehydes in surface waxes of gl5 maize seedlings.

In corn seedlings (Zea mays L.) homozygous for the mutation gl5, the surface waxes are characteristically altered. In this mutant the main wax constituents (83.5%) are aldehydes while in the normal waxes alcohols predominate (62.7%). Moreover, in the normal waxes aldehydes and alcohols are made up mainly of the C32 term (99%), whereas in gl5 waxes the principal aldehyde is still C32 (90.7%) but the free alcohol composition pattern is noticeably modified. Here the predominant terms are C24, C26, and C28, with C32 representing only 16.6% of the total. The results indicate that the mutant induces a block in the synthesis of fatty alcohols while accumulating fatty aldehydes, the substrates from which the alcohols originate.

Aldehydes↗
PubMed1978

Renal micropuncture study of normotensive and Milan hypertensive rats before and after development of hypertension.

Earlier studies of renal transplantation and of sodium metabolism indicated that the cause of high blood pressure in the Milan strain of genetically hypertensive rats (MHS) was altered renal function. To pinpoint the active factors, we used micropuncture to study several indices of renal function in normal (NR) and MHS rats at three different ages: A) 26 to 30 days, before development of hypertension (pre-MHS); B) 35 to 40 days; and C) 75 to 90 days, after the development of hypertension. The indices studied and the important differences found between the two strains were: 1) Single nephron filtration rate (SNFR) and late proximal tubular fluid delivery to the distal nephron (LPF). In group A, the pre-MHS rats had significantly lower values than did the NR (SNFR = 6.3 +/- 0.8 nl/min [MHS] vs. 8.3 +/- 1.2 [NR], P less than 0.01; LPF = 3.14 +/- 0.25 nl/min [MHS] vs. 4.1 +/- 0.35 [NR], p less than 0.05). In group C, the values in the MHS rats were significantly higher than those of the NR (SNFR = 17.3 +/- 1.4 nl/min [MHS] vs. 12.1 +/- 0.8 [NR], P less than 0.05; LPF - 7.4 +/- 0.5 nl/min [MHS] vs. 5.3 +/- 0.3 [NR], P less than 0.01). 2) Number of glomeruli. In group C only, the MHS rats had significantly fewer than did the NR rats (MHS = 55, 253 +/- 2,821 vs. NR = 64,527 +/- 2,900, P less than 0.05). 3) Glomerular filtration rate (GFR) and SNFR as a function of the mean blood pressure (MAP). In group A, the GFR of the MHS rats was lower than that of the NR rats (GFR = 0.38 +/- 0.03 ml/min . 100 g of body wt [MHS], 0.50 +/- 0.03 [NR] P less than 0.05). In group C, there was no longer any significant difference. At equal MAP, SNFR was equal in all the groups, except group A, where SNFR was significantly lower in MHS. 4) Pressure differences: Glomerular capillary pressure (gP). GP was significantly higher in MHS rats than in NR rats (group A, + 5.2 mm Hg; group C, + 6.7 mm Hg). In the pre-MHS rats, anesthesia significantly increased (P less than 0.001) the blood pressure difference between the two strains. This effect was not seen in the adult MHS rats. This may increase the differences in GP between pre-MHS and NR. 5) Afferent effective filtration pressure (EFPA). EFPA values were also higher in MHS rats (+ 2.9 mm Hg in group A, + 6.8 mm Hg in group C), but once again the effects of anesthesia probably account for the differences in magnitude seen between pre-MHS and NR. Only 22% of the absolute differences in systemic arterial pressure in the adult MHS and NR rats was transmitted to the glomerular capillary, while 33% of the difference was transmitted in the younger rats. These values suggest a reduced glomerular hydraulic conductivity, even though other explanations could not be excluded, and they are consistent with the hypothesis that the primary cause of development of hypertension in the MHS rats may be a decrease in SNFR.

Animals↗
PubMed1978

Increase in plasma extracellular fluid volume ratio caused by bilateral nephrectomy in patients on maintenance hemodialysis.

Changes, observed in rats after bilateral nephrectomy, in blood pressure and in the relation betwen plasma volume-extracellular fluid volume or plasma volume-interstitial fluid volume, are consistent with the postulation that the kidney secretes a substance that regulates, to some degree, the compliance of the interstitial space. In order to evaluate the possibility that this also occurs in humans, we have carried out a retrospective analysis of measurements of extracellular fluid volume, plasma volume, and blood volume made prior to and after bilateral nephrectomy in a group of 9 patients. It was observed that significant increases had occurred in both the plasma-extracellular fluid volume ratio (0.22 before, 0.26 after) and in the blood-extracellular fluid volume ratio (0.27 before, 0.32 after). These data are consistent with a reduction in compliance of the interstitial compartment caused by bilateral nephrectomy in man, even though other explanations cannot be excluded.

Adult↗
PubMed1978

Interpersonal factors in suicide attempts: a pilot study in Christchurch.

Attempted suicide is a behavioural pattern with complex psychological and sociological determinants, many of which have been extensively studied in recent years. The basic facts of its changing incidence, its demography, and its place within a broader spectrum of self-destructive behaviour are well established but authorities are still divided on many issues related to its aetiology, its function in the individual and the kinds of services required for its clinical management. (Kessel 1965, Anderson 1974, Weissman 1974, Henderson and Williams 1974). The study reported here was designed partly to define the characteristics of a group of patients for whom clinical services were being planned and partly as a pilot study to develop a methodology for a more extensive controlled study which we hope to carry out next year. The preliminary findings are sufficiently interesting to report now.

Adolescent↗
PubMed1978

[Our experience in the surgical treatment of perforated duodenal ulcer].

The Authors present their surgical experience of more than a decade with regard to emergency therapy of perforated duodenal ulcers. The paper covers the case of 124 patients hospitalized urgently and variously subjected to the aspirative method according to Taylor, raphe, vagotomy and pyloroplasty according to Judd, or immediate gastric resection. With regard to the short, medium and long term results, they conclude in favour of immediate vagotomy, free from dangers and mortality, the fairly positive nature of immediate gastric resection, and the failure or at any rate low reliability of the other two methods used.

Adolescent↗