Publications by authors named "Christine O'Sullivan"
Aim: To establish a basis for rapid remediation of large areas contaminated with Bacillus anthracis spores.
Methods And Results: Representative surfaces of wood, steel and cement were coated by nebulization with B. thuringiensis HD-1 cry- (a simulant for B.
Background: Bioassays evaluating entomopathogenic fungi (EPF) isolates for effective microbial control of whitefly are a fundamental part of the screening process for bioprotectants, but development of repeatable, robust bioassays is not straightforward. Currently, there is no readily available standardised method to test the efficacy of EPF on whitefly. Here, we describe the calibration and use of a spray tower to deliver a standardised protocol to assess EPF activity; the method was validated using 18 EPF from four genera in tests against greenhouse whitefly, Trialeurodes vaporariorum (Westwood).
View Article and Find Full Text PDFNature of exposure is a fundamental driver in nontarget terrestrial plant risk assessment for pesticides; consequently a novel study was designed to generate field-based drift exposure and evaluate corresponding biological effects of the herbicide mesotrione. The approach used a combination of US guideline drift reduction technology and vegetative vigor approaches. In each of 3 independent replicate spray application trials, 10 pots each of lettuce and tomato were placed at distances of 10, 20, 30, 40, and 50 ft (∼3, 6, 9, 12, and 15 m) from the downwind edge of the spray boom.
View Article and Find Full Text PDFAim: To assess right ventricular (RV) function in patients with inferior myocardial infarction (IMI) and to observe changes following thrombolysis.
Background: RV dysfunction occurs in 30% of patients with IMI. The extent of such involvement and its potential, recovery has not been determined.
Background And Aims: Long-term competence of any aortic prosthesis is critical to its clinical durability. Bioprosthetic valves, and in particular the stentless type have been proposed to offer superior haemodynamic profiles with consequent potential for superior left-ventricular mass regression. These benefits however are balanced by the potential longevity of the implanted valve.
View Article and Find Full Text PDFObjective: The objective of this study was to assess natriuretic peptide release following acute myocardial infarction, and its relationship with ventricular function.
Methods: A total of 44 patients with acute myocardial infarction were studied; 13 anterior, age (57+/-12 years) and 31 inferior, age (58+/-12 years). Peptide levels and left ventricular function by echocardiography were assessed at admission and on days 7 and 30 after thrombolysis.
We investigated markers of ischemic dysfunction and their relation to overall right ventricular (RV) performance during dobutamine stress echocardiography in patients who had coronary artery disease. Thirty-three patients (58 +/- 10 years old) who had 3-vessel coronary artery disease were compared with 17 age-matched controls (58 +/- 11 years old). RV long-axis amplitude (M mode), systolic and diastolic myocardial tissue Doppler velocities, and filling and ejection velocities were measured, and cardiac output (CO) was calculated at rest and during peak stress.
View Article and Find Full Text PDFBackground: The mechanism for reduced early diastolic long axis lengthening velocity in hypertrophic cardiomyopathy (HCM) is not known.
Methods: We measured simultaneous septal long axis amplitude and early lengthening velocity in 23 patients with HCM, 23 normal subjects and 22 patients with coronary artery disease (CAD) of left anterior descending artery.
Results: Resting amplitude and lengthening velocity were reduced in HCM 0.
Background: Pharmacological stress is used to assess the degree of left ventricular (LV) subvalvular gradient in patients with hypertrophic cardiomyopathy (HCM), but there is little information about associated physiological changes.
Methods: Echocardiography-Doppler ultrasound scanning measurements in 23 patients with HCM and 23 control subjects of similar age were studied at rest and at the end point of dobutamine stress.
Results: In patients, the systolic time was normal at rest, but increased abnormally with stress.
Background: Pulsed Wave Tissue Doppler (PWTD) recording of myocardial velocities has been widely used for assessing ventricular function but the output trace has finite thickness that leads to potential ambiguity in determining velocity and timing.
Objective: To determine optimal method of measurement of PWTD traces by comparing them with those obtained from digitised M-mode recorded from the atrioventricular (AV) valve ring (septal, LV and RV free wall).
Methods: We studied 100 subjects, 49 normal and 51 with coronary artery disease (15 patients with reduced left ventricular wall motion, mean systolic amplitude of LV free wall 0.
Background: Mustard repair for transposition of the great arteries (TGA) is frequently associated with impaired systemic (right) ventricular function and sometimes exercise intolerance. We hypothesized that a simple quantitative measurement of ventricular function, during rest and pharmacological stress, could identify abnormalities and predict objective exercise capacity.
Methods And Results: We quantified the performance of systemic and pulmonary (left) ventricles by using echocardiography, at rest and during dobutamine stress, in 27 adults who had undergone Mustard repair for TGA.
Objective: To assess the nature of left ventricular (LV) electrical and mechanical dysfunction in Q compared to non-Q anterior myocardial infarction (MI).
Subjects: We used ECG and echocardiography to study 54 unselected patients, age 57+/-15 years, 32 male, with old (>6 months after) anterior MI (39 Q and 15 non-Q), confirmed by enzyme rise and regional wall motion abnormality, and compared them with 21 normals of similar age.
Methods: Analysis of resting LV minor and long axis function and 12-lead surface electrocardiogram.
Background And Aim Of The Study: Although severe tricuspid regurgitation (TR) is a well-recognized, long-term complication of rheumatic mitral valve replacement that impairs the functional results of surgery, its exact basis remains unclear and its management is unsatisfactory. The study aim was to obtain a detailed assessment of tricuspid valve morphology and function using 2D transesophageal echocardiography (TEE) with 3D reconstruction, and to determine long-term clinical outcome in patients after surgery for rheumatic mitral valve disease.
Methods: A total of 42 patients (mean age 50 +/- 10 years) was followed up; 39 patients had mitral replacement and three had valvotomy.
Background: In a small but significant group of elderly patients who present with breathlessness, dynamic left-ventricular outflow tract obstruction (DLVOTO) may be responsible for symptom generation. The aim of our study was to investigate the effect of beta-blockade on ventricular physiology and symptoms in patients with DLVOTO.
Methods: We performed a pilot study in 15 patients (age 76+/-10 years, mean+/-S.
Background: The exact location of a Q wave myocardial infarction has an important effect on overall left ventricular function.
Objectives: To assess the effect of localization of Q wave infarction on left ventricular minor and long axis function, with particular reference to electromechanical disturbances.
Methods: We studied 72 patients with Q wave myocardial infarction; 35 anterior, age 61+/-15 years and 37 inferior, age 62+/-12 years.