Search PubMed⌕ Search

Biomedical subjects

S Goldman

Publications and source records attributed to S Goldman.

At least 343 records · Page 19Linked to original sources
PubMed1987

Dog model to study the effects of pharmacologic agents on the peripheral circulation: effects of milrinone.

To study the effects of an inotropic agent, milrinone, on the entire cardiovascular system, we developed an intact dog model to assess the responses of the heart, arterial and venous circulations. At a dose that increased left ventricular dP/dt by 30% (P less than .001) from 2033 +/- 133 to 2688 +/- 140 mm Hg/sec, milrinone caused a decrease (P less than .001) in mean aortic pressure from 88.4 +/- 3.5 to 73.1 +/- 3.0 mm Hg and cardiac output from 148.0 +/- 14.6 to 134.5 +/- 13.9 ml/kg/min. Heart rate increased (P less than .01) from 124 +/- 8 to 135 +/- 8 beats/min. Systemic vascular resistance did not change. Right atrial pressure and left ventricular end-diastolic pressure decreased (P less than .01). Total blood volume did not change but central blood volume decreased (P less than .01) from 26.1 +/- 0.9 to 22.3 +/- 0.5 ml/kg. After milrinone administration, mean circulatory filling pressure decreased (P less than .01) by 30% from 7.4 +/- 0.4 to 5.0 +/- 0.2 mm Hg. Vascular or venous compliance increased (P less than .05) slightly from 1.96 +/- 0.4 to 2.20 +/- 0.1 ml/mm Hg/kg. This was accompanied by an increase (P less than .01) in unstressed vascular blood volume of 3.3 +/- 0.6 ml/kg. Arterial compliance also increased (P less than .05). In summary, milrinone produces an increase in inotropy, arterial vasodilatation and venodilatation as evidenced by the increased venous compliance and unstressed vascular volume.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Digoxin-diltiazem interaction: a pharmacokinetic evaluation.

The pharmacokinetics of digoxin were studied before and after a 2 week course of diltiazem, 30 mg four times daily, in 7 healthy volunteers. Each subject received an IV dose of digoxin before starting diltiazem and again on day 15 of the study. Diltiazem was continued until all sera and urine were collected. During the control and diltiazem phases, respectively, the terminal elimination rate constants were 0.0231 +/- 0.007 h-1 and 0.0254 +/- 0.007 h-1, the volumes of distribution were 10.5 +/- 3.95 l/kg and 10.2 +/- 3.26 l/kg, and the total body clearances were 3.72 +/- 0.78 ml X min-1 X kg-1 and 4.09 +/- 0.94 ml X min-1 X kg-1. None of these pharmacokinetic parameters of digoxin were significantly different before or during diltiazem administration. Overall, there does not appear to be an interaction between digoxin and diltiazem.

Adult↗
PubMed1986

Bronchoalveolar cell carcinoma of the lung.

A multivariable analysis was performed of all patients registered and confirmed to have bronchoalveolar cell carcinoma of the lung in the Tumor Registry of Thomas Jefferson University Hospital between 1969 and 1983. These 122 patients were reviewed for age, sex, smoking history, occupational exposure, symptoms, radiographic findings, methods of diagnosis, clinical and pathologic staging, methods of treatment, survival, and complications of treatment. No correlation could be found in this series between a patient's age, sex, smoking history, or occupational exposure and the incidence or outcome of the disease. Seventy-one of the 122 patients in this series were asymptomatic, and the carcinoma was discovered in them by routine chest roentgenogram. Of these asymptomatic patients, 50 were seen with pathologic stage I disease. Of the 51 symptomatic patients, 32 (65%) were seen with stage IIIm0 or IIIm1 disease. Despite medical evaluations, 77% of the T1 and T2 lesions required thoracotomy for diagnosis. The overall five-year survival rate was 42.3%, ranging from 75% for those with stage I disease to 8.7% for those with stage IIIm1 disease.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1986

Effects of changes in airway pressure on the left ventricle and left atrium of dogs.

The effects of negative and positive airway pressure were examined in eight closed chest, chronically instrumented dogs to determine beat to beat changes in left ventricular pressure, left ventricular dP/dt, left ventricular dimensions, and oesophageal pressure. As an index of afterload, systolic transmural pressure was calculated by subtracting oesophageal pressure from left ventricular pressure. With each change in airway pressure left ventricular end systolic minor axis diameter and left ventricular end diastolic minor axis diameter increased significantly. Left atrial end diastolic dimension increased significantly with negative airway pressure and did not change with positive airway pressure. Left ventricular dP/dt and left ventricular fractional shortening did not change. With the Mueller manoeuvre left ventricular systolic pressure decreased significantly from 106(4.2) mm Hg to 100.9(4.2) mm Hg and systolic transmural pressure increased significantly from 105.1(4.6) mm Hg to 110.4(4.3) mm Hg. With a transient increase in positive airway pressure of 30 mm Hg (4.0 kPa), left ventricular pressure increased significantly from 106.9(4.8) mm Hg to 113.9(5.9) mm Hg and systolic transmural pressure decreased significantly from 106.6(4.9) mm Hg to 99.8(4.6) mm Hg. The addition of positive end expiratory pressure of 10 cm H2O (0.98 kPa) or autonomic blockade with atropine and propranolol did not alter these results. Thus manoeuvres which cause opposite effects on systolic transmural pressure produce similar increases in left heart dimensions, suggesting that increases in pulmonary venous return and not changes in afterload may be the important determinants of left ventricular dimensional changes during changes in airway pressure.

Animals↗
PubMed1986

Alpha 1- and alpha 2-adrenoceptor stimulation: changes in venous capacitance in intact dogs.

The peripheral circulatory effects of alpha 1-adrenoceptor stimulation with methoxamine hydrochloride were compared with those of alpha 2-stimulation with UK 14304-18 in 12 intact dogs. Doses of each agent were infused to increase systemic vascular resistance and arterial pressure 50 and then 100% above control. Heart rate was controlled with atropine. At the higher dose, methoxamine increased mean aortic pressure (PAo) from a control of 77.3 +/- 1.6 to 152.9 +/- 3.2 mmHg, mean circulatory filling pressure (MCFP) from 8.0 +/- 0.4 to 13.3 +/- 1.3 mmHg, and central blood volume (CBV) from 21.3 +/- 1.1 to 25.9 +/- 1.5 ml X kg-1, whereas cardiac output did not change. UK 14304-18 increased PAo from 78.1 +/- 2.6 to 148.9 +/- 2.7 mmHg, MCFP from 7.9 +/- 0.4 to 10.6 +/- 0.4 mmHg, and CBV from 21.0 +/- 1.1 to 24.1 +/- 1.5 ml X kg-1, whereas cardiac output decreased from 151.7 +/- 9.4 to 126.3 +/- 5.8 ml X kg-1 X min-1. Mean circulatory filling pressure and CBV were higher with methoxamine than with UK 14304-18. Effective vascular compliance, determined by serial measurements of MCFP during ganglionic blockade after rapid changes in blood volume, decreased from a control value of 1.9 +/- 0.1 to 1.3 +/- 0.3 ml X mmHg-1 X kg-1 with methoxamine, but did not change with UK 14304-18 (1.9 +/- 0.1 ml X mmHg-1 X kg-1). At any given change in blood volume, there was a higher MCFP with alpha 1-stimulation compared with alpha 2-stimulation. Both agents decreased unstressed vascular volume.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Total vascular pressure-volume relationship in conscious rats with chronic heart failure.

To define the changes in the venous circulation in chronic left ventricular (LV) failure, we measured the mean circulatory filling pressure (MCFP), blood volume, and effective vascular compliance in conscious rats with heart failure, 3 wk after coronary ligation. Rats with myocardial infarction and LV end-diastolic pressure (EDP) greater than 15 mmHg were considered to have chronic heart failure. Rats with chronic heart failure (n = 11) showed an increase (P less than 0.001) in LV EDP to 24 +/- 2 mmHg compared with 6 +/- 1 mmHg in sham-operated (n = 9) and 7 +/- 1 mmHg in normal (n = 6) rats. In the rats with chronic heart failure the MCFP was increased to 9.9 +/- 0.2 mmHg (P less than 0.001) compared with 7.6 +/- 0.2 mmHg in the sham-operated and 7.7 +/- 0.2 mmHg in the normal rats. Effective vascular compliance was determined from MCFP-blood volume curves. In rats with chronic heart failure, the effective vascular compliance was decreased to 2.40 +/- 0.08 ml X mmHg-1 X kg-1 from 3.34 +/- 0.16 in sham-operated rats and 3.35 +/- 0.22 ml X mmHg-1 X kg-1 in normal rats. The blood volume and the unstressed vascular volume of the rats with chronic heart failure were not statistically different from the sham-operated rats. These results suggest that venous capacitance is decreased in chronic heart failure, due to a decrease in effective vascular compliance with no significant change in unstressed vascular volume. Hexamethonium chloride did not alter the effective vascular compliance of the rats with heart failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Preliminary study of the effects of low flow oxygen on oxygen delivery and right ventricular function in chronic lung disease.

This study was designed to test the feasibility of using the noninvasive radionuclide measurement of the right ventricular ejection fraction (RVEF) to identify which patients with chronic lung disease objectively benefit from low flow oxygen therapy. Two categories of benefit, pulmonary artery pressure/resistance and peripheral oxygen delivery, were examined in 19 patients. Fourteen subjects returned after at least 3 wk of continuous low flow oxygen therapy for restudy; 12 patients had complete radionuclide and hemodynamic data. The change in RVEF, in response to continuous oxygen, correlated significantly with the change in coefficient of oxygen delivery (r = 0.59, p less than 0.05) and the change in cardiac output (r = 0.62, p less than 0.05). The change in RVEF did not correlate significantly with the change in pulmonary artery pressure (r = 0.06) or the change in total pulmonary resistance (r = -0.35). The change in coefficient of oxygen delivery, representing oxygen delivery corrected for oxygen consumption, correlated positively with change in cardiac output (r = 0.58, p less than 0.05) and negatively with change in oxygen consumption (r = -0.63, p less than 0.05), arterial oxygen content (r = -0.63, p less than 0.05), and arterial oxygen tension (r = -0.61, p less than 0.05). That is, the fall in hemoglobin in these patients more than compensated for any increase in Pao2 so that improved oxygen delivery frequently occurred despite a decrease in arterial oxygen content, and improved oxygen delivery occurred for the most part among patients with smaller improvement in Pao2.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Treatment of verapamil toxicity in intact dogs.

The treatment of verapamil toxicity was examined in lightly sedated dogs. Verapamil, administered as a bolus (0.72 mg/kg) followed by a continuous infusion (0.11 mg/kg per min), decreased cardiac output (CO) from 3.1 +/- 0.1 to 1.7 +/- 0.1 liter/min (P less than 0.001), heart rate (HR) from 85 +/- 4 to 57 +/- 3 beats/min (P less than 0.001), left ventricular derivative of pressure with respect to time (LV dP/dt) from 2,085 +/- 828 to 783 +/- 78 mm Hg/s (P less than 0.001), mean aortic pressure (AO) from 77 +/- 4 to 38 +/- 2 mm Hg (P less than 0.001) and stroke volume from 39 +/- 3 to 28 +/- 2 ml/beat (P less than 0.01). In verapamil-toxic animals isoproterenol increased HR, CO, LV dP/dt, and AO; calcium chloride increased LV dP/dt and AO; norepinephrine, epinephrine, and dopamine increased CO, AO, and LV dP/dt, atropine increased HR, CO, and AO. Phenylephrine (13-55 micrograms/kg per min) produced no changes except a small increase in AO while very high dose phenylephrine (300 micrograms/kg per min) increased AO, CO, and LV dP/dt. 4-Aminopyridine (4-AP) increased HR, CO, LV dP/dt, and AO. When administered prior to verapamil, 4-AP prevented the development of verapamil toxicity as shown by the significantly higher AO (P less than 0.001), CO (P less than 0.01), and LV dP/dt (P less than 0.01) when 4-AP followed by verapamil was compared to verapamil alone. In conclusion, there does not appear to be a single specific therapy for verapamil toxicity, however it can be partially corrected by presently available pharmacologic therapy and 4-AP.

4-Aminopyridine↗
PubMed1986

Results of surgical treatment of coarctation of the aorta in the critically ill neonate. Including the influence of pulmonary artery banding.

During a 7 year period, 64 consecutive neonates (less than 30 days of age) underwent surgical repair of coarctation of the aorta. There were no intraoperative deaths, four (6%) postoperative deaths, and seven (12%) late deaths. Improvement in the survival rate in this study can be attributed to improved perioperative care, avoidance of hypothermia during the operation, use of prostaglandin E1 to stabilize the patient's condition before the operation, emergency cardiac catheterization and operations, adequate relief of the aortic obstruction, and appropriate use of pulmonary artery banding. The last of these factors may further reduce the mortality. Banding of the pulmonary artery in patients with complex cardiac lesions associated with a ventricular septal defect has significantly lowered the mortality compared with the mortality of those without pulmonary artery banding. In contrast, the absence of pulmonary artery banding in those with a large ventricular septal defect did not affect the mortality or postoperative ventilator requirements as compared to patients having banding and coarctation repair. One late death was related to complications of the pulmonary artery band.

Aortic Coarctation↗
PubMed1985

Squamous-cell carcinoma of the anus. A follow-up study of 65 patients.

The five-year survival rate in 72 patients who underwent treatment for squamous-cell carcinoma of the anus in Stockholm County (1972 to 1978) has been studied. There were no differences in survival rates after rectum-preserving treatment (mainly consisting of irradiation +/- cytostatics +/- local excision) as compared with extensive surgery (abdominoperineal resection), even if the tumor size, location, and differentiation were taken into consideration. It therefore seems appropriate to suggest irradiation +/- cytostatics as the therapy of choice regardless of size, location, and differentiation of the tumor.

Adult↗
PubMed1985

Intraoral benign mesenchymoma.

Benign mesenchymoma is a tumor composed of two or more benign mesenchymal elements in addition to fibrous connective tissue. A case of benign mesenchymoma of the lip in a 38-year-old man is presented, and the literature is reviewed.

Adult↗
PubMed1985

Right ventricular function at rest and during exercise in aortic and mitral valve disease.

Right ventricular function at rest and during exercise was examined in a group of patients with symptomatic aortic or mitral valve disease, or both. The right ventricular ejection fraction was less than 45% in 22 of 36 patients at rest and in 12 of 17 subjects at symptom-limited, supine bicycle exercise. The right ventricular ejection fraction failed to increase more than 5% with exercise in 17 of 17 patients. The central venous pressure was greater than 5 mm Hg in 18 of 36 patients at rest and in 13 of 17 patients at maximal exercise. There was a significant inverse relation between rest right ventricular ejection fraction and mean pulmonary artery pressure (r = -0.47, p less than 0.05) and between rest right ventricular ejection fraction and mean central venous pressure (r = -0.39, p less than 0.05). There was no significant relation between the exercise values of these variables. In individual patients, the changes in right ventricular ejection fraction and pulmonary artery pressure with graded exercise were nonlinear. It is concluded that right ventricular function is not a simple function of pulmonary artery pressure at rest or during exercise in aortic and mitral valve disease. Less than one-quarter of the variation in right ventricular ejection fraction at rest can be explained by the variation in pulmonary artery pressure, and the finding of a normal (greater than 45%) right ventricular ejection fraction does not reliably exclude the possibility of pulmonary hypertension in a patient with valvular heart disease.

Adult↗
PubMed1985

Co-existence of cholecystokinin- or gastrin-like peptides with other peptides in the hypophysis and the hypothalamus.

The presence of cholecystokinin and gastrin has been reported in the hypothalamohypophyseal system. These peptides present a peculiar distribution in the hypothalamic nuclei, the median eminence, and the neurohypophysis. CCK and gastrin have close relationships with other peptides like oxytocin, CRF, vasopressin, and the enkephalins; these relationships vary in different projecting areas and in different types of hypothalamic neurons. The functional role of G-CCK in neurosecretion seems to be linked to the role of these closely associated peptides and certainly deserves further investigation.

Animals↗
PubMed1985

Remission of invasive thymoma due to chemotherapy. Two patients treated with cyclophosphamide, doxorubicin, and vincristine.

Information regarding the effectiveness of chemotherapy in cases of invasive thymoma is limited. Two patients in whom the combination of cyclophosphamide, doxorubicin, and vincristine produced remission of invasive thymoma are described. The durations of remission were eight and seven months, respectively. In both patients, recurrence was observed at the site of bulky disease, and a secondary complete response continuing for 37 months was achieved in one of them with radiation therapy.

Aged↗
PubMed1985

Alpha-1 adrenergic control of the venous circulation in intact dogs.

To study alpha adrenergic control of the venous circulation, 17 dogs were lightly sedated and instrumented with thermodilution pulmonary flow and aortic catheters. Hemodynamics, cardiac output and central blood volume were measured at rest. Mean circulatory filling pressure, pressure gradient for venous return and resistance to venous return were calculated from pressures obtained during transient acetylcholine-induced circulatory arrest. Phenylephrine was then infused at two steady-state levels to increase mean aortic pressure by 50 and 100% above control values. Heart rate was controlled with atropine. Phenylephrine increased (P less than .025) mean aortic pressure from 80.7 +/- 2.9 to 121.3 +/- 7.6 to 164.7 +/- 6.1 mm Hg and systemic vascular resistance from 23.3 +/- 2.0 to 32.2 +/- 3.5 to 43.5 +/- 4.1 mm Hg/min/ml and did not change cardiac output (161.9 +/- 12.6-175.6 +/- 13.8-169.6 +/- 11.9 ml/min/kg). Mean circulatory filling pressure increased from 7.1 +/- 0.5 to 9.7 +/- 0.6 to 13.2 +/- 1.3 mm Hg (P less than .025). Pressure gradient for venous return increased from 6.4 +/- 0.4 to 7.7 +/- 0.4 to 8.9 +/- 0.4 mm Hg (P less than .025). Central blood volume increased from 16.2 +/- 0.9 to 19.4 +/- 1.4 to 22.0 +/- 1.9 ml/kg (P less than .025). To eliminate reflex changes in vascular tone, eight dogs received ganglionic blockade with trimethaphan. After ganglionic blockade phenylephrine increased cardiac output, systemic vascular resistance, mean circulatory filling pressure, pressure gradient for venous return and central blood volume (P less than .025). Thus, in conscious dogs, phenylephrine reduces peripheral vascular capacitance and shifts blood from the venous circulation to the central and arterial vascular compartments.

Animals↗
PubMed1985

Studies on phase variation in Bordetella pertussis.

Pathogenic strains of Bordetella pertussis undergo spontaneous phase variation and become non-pathogenic upon culturing in vitro. The spontaneous process was studied in pathogenic B. pertussis strains Tohama, 165 and 18323 by isolating spontaneous variants, selected for their ability to grow on synthetic and semi-synthetic solid media. In strains Tohama and 165, the frequency of variants able to grow on synthetic and semi-synthetic media was between 10(-6) and 10(-7). About 250 variant strains were screened for the presence of virulence-associated traits, such as production of hemolysin, pertussis toxin and filamentous hemagglutinin (FHA). Only four different combinations of the traits were found: 7-11% of the variants displayed all traits, 17% of the variants carried pertussis toxin and FHA, 5-11% carried FHA only and 66% were devoid of all virulence traits. The strains which had at least one virulence trait also demonstrated some adenylate cyclase activity. The disappearance of hemolysin was related quantitatively to the other traits. These results suggest that phase variation in B. pertussis is a non random process, involving ordered disappearance of virulence factors in the following order: hemolysin, pertussis toxin and FHA. Since all the variant strains were phenotypically stable upon further passaging in vitro, they represent the stable, final outcome of the variation process which may have occurred in "Phase I" colonies. In contrast, 300 variants of B. pertussis 18323, which were able to grow on selective solid media, carried all the virulence traits. This is in accordance with the strain's unique intracerebral virulence.

Adaptation, Physiological↗