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B McConville

Publications and source records attributed to B McConville.

12 recordsLinked to original sources
PubMed2001

Transdermal nicotine and haloperidol in Tourette's disorder: a double-blind placebo-controlled study.

BACKGROUND: Preclinical animal and open-trial clinical trials using nicotine gum and the transdermal nicotine patch found that treatment with nicotine potentiates the effects of neuroleptics in reducing the dyskinetic symptoms of Tourette's disorder. We sought to verify and expand these findings in a prospective double-blind placebo-controlled trial. METHOD: Seventy patients with DSM-IV Tourette's disorder were treated with either transdermal nicotine (7 mg/24 hours) or placebo patches in a 33-day, randomized, double-blind study. Each patient received an individually based optimal dose of haloperidol for at least 2 weeks prior to random assignment to nicotine or placebo treatment. A new patch was worn each day for the first 5 days. On the sixth day, the dose of haloperidol was reduced by 50%. Daily patch applications were then continued for an additional 2 weeks (through day 19), at which time the patch was discontinued, but the 50% dose of haloperidol was continued for an additional 2 weeks (through day 33). Clinical and safety assessments were made at each visit. RESULTS: Patients who completed all 19 days of nicotine (N = 27) or placebo (N = 29) patch treatment were used in efficacy analyses. As documented by the Clinician- and Parent-rated Global Improvement scales, transdermal nicotine was superior to placebo in reducing the symptoms of Tourette's disorder. The Yale Global Tic Severity Scale was less sensitive in detecting a placebo/drug difference than were the global improvement scores, suggesting that some of the improvement may not have been related to treatment-related changes in tic severity, but to the emotional and behavioral symptoms. The side effects of nausea and vomiting were significantly more common in the nicotine group (71% [N = 25] and 40% [N = 14]) than in the placebo group (17% [N = 6] and 9% [N = 3]) (nausea, p = .0001; vomiting, p = .004). CONCLUSION: Transdermal nicotine was superior to placebo in reducing behavioral symptoms when patients were receiving an optimal dose of haloperidol, when the dose of haloperidol was reduced by 50%, and when the patch had been discontinued for 2 weeks. These findings confirm earlier open-label findings and suggest that combining nicotinic receptor modulation and neuroleptics could be a therapeutic option for the treatment of Tourette's disorder. While side effects limit chronic use of nicotine, it may be useful on a p.r.n. basis. Further clinical research is warranted to investigate the use of novel nicotinic receptor modulating agents with improved safety profiles over nicotine.

Administration, Cutaneous↗
PubMed1991

Comparison of functional and metabolic assessments in preservation techniques for heart transplantation.

The present study compares simple hypothermic storage and hypothermic perfusion in a swine model of heart transplantation using metabolic and functional assessments. In both groups the hearts were initially protected with iso-osmolar potassium Tyers' cardioplegia. The donor hearts of group A were placed in simple hypothermic storage for 5 h. The donor hearts of group B were placed onto a perfusion apparatus for 5 h with perfusion pressure maintained at 28 cm of H2O and a myocardial temperature of 8-10 degrees C. The perfustate consisted of Tyers' solution with the addition of 2 mg/L of mannitol, 12.5 mg/L of glucose, 5 units/L of insulin, and 95% oxygen. The ischemic interval within both groups was 6 h, including orthotoipic transplantation. Investigation was conducted at three time periods: prepreservation (T1) in the donor, and postpreservation (T2) and immediately after loading (T3) in the recipient. Following volume loading for the hypothermic perfusion group there was significant improvement of myocardial function (cardiac index, p less than .05; stroke index, p less than .05) with no significant change in systemic vascular resistance, systemic blood pressure, and heart rate. There was also significant improvement in myocardial performance (p less than .05) for the hypothermic perfusion group following volume loading. Results of fatty acid turnover using 15-p-iodo (123I)-phenylpentodecanoic acid indicate significantly greater increase in metabolic rate for the perfusion group than for the hypothermic storage group. (p less than .05). This indicates improved metabolic status of the heart treated with the hypothermic perfusion technique. We conclude that a combination of functional and metabolic assessments is a good method for deduction of ischemic-reperfusion injury. We also conclude that hypothermic perfusion is superior to hypothermic storage for in vitro preservation of hearts for heart transplantation.

Animals↗
PubMed1989

Evaluation of ventricular contractility indexes in the dog with left ventricular dysfunction induced by rapid atrial pacing.

Eight dogs were studied by simultaneous invasive hemodynamic and two-dimensional echocardiographic methods to determine whether left ventricular contractility is altered by 2 weeks of rapid atrial pacing. Additionally, this study evaluated the response of three ventricular contractility indexes to both the pacing intervention and acute load alteration. The indexes compared were ejection fraction, peak systolic pressure to end-systolic volume index ratio (SBP/ESVI) and end-systolic wall stress to end-systolic volume index ratio (ESWS/ESVI). After 2 weeks of pacing at 265 +/- 20 min-1 (mean +/- SD), cardiac index and ejection fraction were reduced to 73 +/- 38 ml/kg per min and 22 +/- 6%, respectively, from 161 +/- 22 and 46 +/- 7 before pacing (both p less than 0.001). Concomitantly, SBP/ESVI and ESWS/ESVI were reduced to 34 +/- 10 mm Hg/ml per kg and 54 +/- 19 g/cm2 per ml per kg, respectively, from 84 +/- 29 and 121 +/- 36 before pacing (both p less than 0.005). There were high correlations for the changes in SBP/ESVI and ejection fraction (r = 0.94, p less than 0.001) and ESWS/ESVI and ejection fraction (r = 0.89, p less than 0.003). Acute afterload alteration with phenylephrine depressed ejection fraction but not SBP/ESVI or ESWS/ESVI. Therefore, this study demonstrates 1) that left ventricular contractility is markedly depressed in the dog by 2 weeks of rapid atrial pacing, and 2) that SBP/ESVI and ESWS/ESVI are superior to ejection fraction as ventricular contractility indexes because these ratios accurately measure contractility changes but are influenced less by after-load conditions.

Animals↗
PubMed1986

Noninvasive determination of valve area in adults with aortic stenosis using Doppler echocardiography.

Doppler ultrasound has been used to determine the pressure gradient P1-P2 across the valve in patients with aortic stenosis (AS), but since the gradient varies over time and may be deceptively low in patients with impaired cardiac output, the key parameter to obtain is the orifice area (A). By calculating stroke volume (SV) from the modal flow velocity [Vmode(t)] over the systolic ejection period (sep) or diastolic filling period (dfp), wherever laminar flow exists in the heart across an area of known diameter D, (pulmonary artery or atrioventricular valves), and by substituting P1-P2 = 4Vmax2, (Vmax = peak velocity in the aortic jet), the Gorlin formula becomes: (Formula: see text) where theta = flow intercept angle at D. This approach was applied in nine adult patients with AS (age 64 +/- 8 years) in whom recent catheterization data was available for comparison. Close correlation was found between the calculated areas: A(Doppler) = 0.82 A(Cath) + 0.17 (r = 0.94, p less than 0.001). Two patients with Doppler gradients of less than 40 mmHg were shown by this Doppler method nevertheless to have severely narrowed orifice areas of less than or equal to 0.78 cm2. Although there is a tendency to overestimate slightly the valve area, Doppler ultrasound assessment using this technique adds valuable noninvasive information concerning the degree of aortic valve disease.

Aged↗
PubMedDate not supplied

Control of oxygen cytotoxicity with allopurinol and superoxide dismutase: a canine model of global myocardial ischemia-reperfusion injury.

The purpose of this study was to assess the effects of acute pharmacological interventions on the ischemia-reperfusion damage in a canine model of hypothermic global myocardial ischemia. Three experimental groups each consisting of seven animals were subjected to 2 h of global ischemia followed by 1 h of reperfusion. Group A (control) used Tyers' iso-osmolar potassium cardioplegia solution; group B received allopurinol (40 mg/kg), 95% intravenously (IV) systemically with 5% added to the final infusion of Tyers' solution. In group C, superoxide dismutase (6.5 mg/kg) was used, one third of the total dose in the final delivery of the Tyers' cardioplegia solution and two thirds IV during the initial 5 min of reperfusion. In all three groups, myocardial temperature was maintained between 15 and 19 degrees C. Methods of evaluation included hemodynamic and echocardiographic parameters of ventricular function. Assessment was performed at three time periods: pre-cardiopulmonary bypass (control), 60 min postreperfusion and immediately post-volume loading (at 2 h after cardiopulmonary bypass). No significant deterioration of myocardial function was observed in either of the experimental groups after the use of these preservation techniques. Comparison of regression slopes based on analysis of covariance for myocardial performance, systolic function, and diastolic compliance did not demonstrate any significant differences between the groups. Two hours of global ischemia was not sufficient to cause measurable damage to the myocardium on the basis of which the pharmacological intervention with allopurinol and superoxide dismutase could be evaluated. The controversy surrounding the use of allopurinol and superoxide dismutase is discussed with the findings of this experimental protocol and is brought up for scientific dialogue.

Allopurinol↗
PubMedDate not supplied

Preservation techniques for heart transplantation: comparison of hypothermic storage and hypothermic perfusion.

Preservation of the donor heart is an important and controversial subject in heart transplantation. This study compares simple hypothermic storage and hypothermic perfusion in a swine model of heart transplantation (n = 14). The donor hearts of group A (n = 7) were placed in simple hypothermic storage for 5 hours. The donor hearts of group B (n = 7) were placed onto a perfusion apparatus for 5 hours, with pressure maintained at 28 cm of H2O and a myocardial temperature of 8 to 10 degrees C. In both groups the hearts were initially protected with isosmolar potassium cardioplegic solution. The perfusate in group B contained moderate sodium, mannitol, glucose, insulin, and oxygen. The ischemic interval within both groups was 6 hours including orthotopic transplantation. Investigation was conducted at three time periods: prepreservation, postpreservation, and immediately after loading. For both groups there was nonsignificant depression of myocardial function (cardiac index, stroke index, stroke work index, ejection fraction, and wall stress) at the postpreservation period. After volume loading, for the hypothermic perfusion group there was significant improvement of myocardial function (cardiac index, p less than 0.01; stroke index, p less than 0.01) with no significant change in heart rate, systemic vascular resistance, and systolic blood pressure. There was also significant improvement in myocardial performance (p less than 0.05) for the hypothermic perfusion group after volume loading. Ultrastructural changes were minimal for both groups, and there were no major heart transplantation after 6 hours of ischemia; however, hearts retain their contractile capacity better after hypothermic perfusion than after simple hypothermic storage.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

A bloody tradition.

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Circumcision, Female↗