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Biomedical subjects

H G Hanley

Publications and source records attributed to H G Hanley.

At least 37 records · Page 2Linked to original sources
PubMed1980

Limitations of post-extrasystolic potentiation in assessing regional myocardial viability in man.

UNLABELLED: To investigate the usefulness of regional response to post-extrasystolic potentiation as a predictor of left ventricular viability in patients with coronary artery disease, 46 patients underwent calibrated biplane left ventricular cineangiography during which a single, timed ventricular premature contraction was introduced. RESULTS: Of 758 normal or hypokinetic segments, 486 (64.1%) showed a positive response to post-extrasystolic potentiation. Of 116 akinetic or dyskinetic segments, only 51 (43.9%) showed a positive response to post-extrasystolic potentiation (P less than 0.001). Because akinetic or dyskinetic areas would not be expected to respond to post-extrasystolic potentiation based on animal laboratory data, alternative explanations were sought to explain such positive response in man. Analysis of percent change in chord length of normal or hypokinetic segments adjacent to akinetic or dyskinetic segments that did or did not respond to post-extrasystolic potentiation revealed (10.2% +/- 1.2%) vs (1.3% +/- 0.7%) improvement, respectively (P less than 0.001) (mean +/- SE). CONCLUSION: Passive rather than active events may be responsible for "improved" regional wall motion following post-extrasystolic potentiation in akinetic or dyskinetic regions. If unrecognized, these factors may lead to improper interpretation of "intervention ventriculography" utilizing post-extrasystolic potentiation.

Angiocardiography↗
PubMed1979

Consequences of vasectomy: an immunological and histological study related to subsequent fertility.

Studies of 2 groups of patients 2 years and 8 years following vasectomy failed to demonstrate evidence of cell mediated immunity to sperm. Histological examination of testicular tissue from 11 patients undergoing reversal of vasectomy showed significant abnormalities in each. However, subsequent fertility within 15 months occurred in 7 (63.6%) of these patients. The nature of the testicular changes and the possible aetiological factors are discussed.

Adult↗
PubMed1979

Biochemical and morphological correlates of acute experimental myocardial ischemia in the dog. IV. Energy mechanisms during very early ischemia.

Tissue energy metabolism was examined in posterior (ischemic) and anterior ("control") regions of canine ventricles after 5 and 10 minutes of left circumflex coronary artery occlusion. When compared to identical regions of normal hearts, the following changes were found: (1) decreases in glycogen and phosphorylase activity in the anterior and posterior regions, (2) depressed state 3 rates of oxygen consumption of isolated mitochondria in both anterior and posterior regions, (3) shifts in optimum substrate concentrations for palmityl-CoA (+ carnitine) oxidation by mitochondria in the anterior and posterior regions, and (4) decreases in the apparent zero order and first order rates of mitochondrial palmitylcarnitine production. These changes correlated with a marked decrease in developed tension in the posterior regions. Depression in tension development in the posterior regions of the heart still was present after 30--60 minutes of reperfusion following a 10-minute period of occlusion. Glycogen content in the reperfused areas was significantly decreased after 60 minutes of reperfusion when compared to normal areas and to control hearts perfused for 70 minutes. After reperfusion, mitochondrial function appeared to return toward "normal." However, the slow restoration of contraction of the ischemic area suggests that cellular mechanisms operative in vivo to restore pump function still might be abnormal.

Acyl Coenzyme A↗
PubMed1978

Fulminant beriberi heart disease with lactic acidosis: presentation of a case with evaluation of left ventricular function and review of pathophysiologic mechanisms.

Cardiac beriberi is considered a rare disease in western society. A patient with fulminant Shoshin-type beriberi was studied in the acute phase and found to have severe metabolic acidosis, high output biventricular failure, and markedly low systemic vascular resistance. Red blood cell transketolase activity was abnormally low. Following treatment with thiamine, diuretics, digitalis and oxygen, all abnormalities disappeared. The historical background of the disease is reviewed along with a discussion of pathophysiologic mechanisms responsible for the hemodynamic profile and lactic acidosis. Angiographic and hemodynamic data on the patient presented suggest relative depression of left ventricular function in the acute phase of beriberi. Since beriberi is uncommonly encountered, emphasis is placed on diagnostic and therapeutic implications of the disease which may not be widely appreciated.

Acidosis↗
PubMed1977

Hyperserotonemia and amine metabolites in autistic and retarded children.

Mean whole blood serotonin (5-HT) levels were elevated in groups of autistic and severely retarded children. Eight of 27 (30%) individual autistic children, 13 of 25 (52%) severely retarded children, two of 23 (9%) mildly retarded children, and none of the control children had statistically significant blood 5-HT levels elevations (hyperserotonemia). Hyperserotonemic autistic children excreted more urinary 5-HT, 5-hydroxyindoleacetic acid (5-HIAA), tryptamine, and vanillylmandelic acid than did mildly retarded children with normal blood 5-HT levels. Rates of depletion and repletion of blood 5-HT levels in these two groups following reserpine therapy were identical. Oral tryptophan administration doubled urinary 5-HIAA excretion in both groups and raised urinary 5-HT levels in hyperserotonemic autistic children, but lowered urinary 5-HT in mildly retarded, normal blood 5-HT children. No clear mechanism for hyperserotonemia was found; the rationale for further investigations is discussed.

Adolescent↗
PubMed1977

Postextrasystolic compliance of the left ventricle.

The effects of a single premature contraction (PC) on left ventricular diastolic distensibility was studied in man, in the conscious chronically instrumented dog, and in the isolated (isovolumic) blood perfused dog heart. In the isolated dog heart at a constant volume, there was no difference in end-diastolic pressure when control diastolic pressure was compared to that following a PC. In man and conscious dogs, there was no difference between the overall pressure-volume or pressure-length plots when control diastolic data were compared to data from the diastole immediately following a PC (no change in the modulus of chamber stiffness). In the intact circulation of man dog, increased filling during the post PC pause causes the ventricle to operate higher on the steep (stiffer) portion of its pressure-volume or pressure-length curve (decrease in preload-dependent compliance). Thus, although a PC does not alter the modulus of chamber stiffness, a preload-dependent change in compliance may occur during post PC diastole.

Animals↗
PubMed1977

Comparison of allergic aspermatogenesis with that induced by vasectomy. II. In vitro studies of cell-mediated immunity to sperm after vasectomy in man and guinea-pig.

Transformation of peripheral blood leucocytes was shown to be a valid assay for cell-mediated immunity to sperm in male guinea-pigs immunized with homologous epididymal sperm (ES) in FCA. A heat-treated extract of ES (BES) was used for culture. Possible developement of cell-mediated immunity to sperm after vasectomy was investigated in patients and guinea-pigs, by culture of blood leucocytes before and at intervals after operation. Patients' leucocytes were cultured with a heat-treated extract of human seminal sperm (BHS); guinea-pigs' leucocytes were cultured with BES. These cultures showed no evidence of specific stimulation of leucocytes by sperm extract, up to 1 year after vasectomy in patients, or up to 6 months in guinea-pigs. Similarly, no evidence of delayed hypersensitivity could be demonstrated by skin tests with BES in animals vasectomized 1 year previously. We consider that this study establishes that cell-mediated immunity to sperm does not develop in either man or guinea-pigs, up to 1 year after conventional vasectomy.

Animals↗
PubMed1976

Comparison of allergic aspermatogenesis with that induced by vasectomy. I. In vivo studies in the guinea-pig.

Groups of male and female guinea-pigs were immunized with homologous epdidymal sperm in Freund's complete adjuvant (FCA) and skin tested at weekly intervals with a heat-treated extract of the sperm or with PPD. In females, the skin response to both antigens was similar to that to any standard protein antigen. In males, the response to sperm extract varied with the induced auto-immune orchitis, reaching a maximum immediately after testis lesion was most severe and as recovery was beginning (shown histologically): the response to PPD was decreased at 1 week after immunization, but subsequently was similar to that in females. Skin tests on guinea-pigs 8 months after bilateral vasectomy (when both ends of vasa were ligated), showed no evidence of delayed hypersensitivity to sperm, although there was marked histological evidence of reduced spermatognesis, due to back pressure atrophy.

Animals↗
PubMed1975

Effects of an inotropic agent, RO 2-2985 (X-537A), on regional blood flow and myocardial function in chronically instrumented conscious dogs and anesthetized dogs.

RO 2-2985 produced a marked positive inotropic effect in unanesthetized, chronically instrumented dogs, measured as an increase in left ventricular dP/ dt and an increase in maximum velocity of myocardial fiber shortening. Similar changes produced in dogs in hemorrhagic shock lasted for 2-3 hours. RO 2-2985 increased peripheral blood flow and caused marked increases in both coronary and renal blood flows. The drug altered the response of the renal vascular bed to subsequent norepinephrine administration. After administration of a single dose of RO 2-2985, norepinephrine produced sustained increases in renal blood flow, and this altered responsiveness to norepinephrine persisted for periods ranging from 1 to 3 weeks.

Anesthesia↗