PubMed Health⌕ Search

Biomedical subjects

S Meikle

Publications and source records attributed to S Meikle.

17 recordsLinked to original sources
PubMed1996

Electrocardiographic measurement of infarct size after thrombolytic therapy.

OBJECTIVES: We examined the utility of the 32-point QRS score from the 12-lead electrocardiogram (ECG) for measurement of the ischemic risk region and infarct size in patients receiving thrombolytic therapy. BACKGROUND: The QRS score offers a means of evaluating the therapeutic benefit of thrombolytic therapy by comparing final infarct size with the initial extent of ischemic myocardium. METHODS: The study included 38 patients (34 men, 4 women; mean [+/-SD] age 54 +/- 10 years) with a first infarction (18 anterior, 20 inferior). The maximal potential QRS score (QRS0) was assigned to all leads with >/= 100-microV ST elevation on the initial ECG. The QRS scores were calculated at 7 and 30 days after infarction. Left ventricular ejection fraction was measured by radionuclide ventriculography at 1 month. Twenty-eight patients had thallium (Tl)-201 and technetium (Tc)-99m pyrophosphate tomographic measurement of the ischemic region and infarct size. RESULTS: The QRS0 was 10.3 +/- 3.1 (mean +/- SD) for anterior and 10.4 +/- 3.5 for inferior infarcts. The QRS scores were similar at 7 and 30 days for both anterior (5.6 +/- 3.4 vs. 5.5 +/- 3.4) and inferior infarcts (3.7 +/- 2.6 vs. 2.9 +/- 2.2). The day 7 QRS score and ejection fraction at 1 month were inversely correlated (r = -0.74, p < 0.01). The Tl-201 perfusion defect was 34 +/- 11% of the left ventricle for anterior and 32 +/- 7% for inferior infarcts. Subsequent Tc-99m pyrophosphate infarct size was 15 +/- 9% of the left ventricle for anterior and 17 +/- 9% for inferior infarcts. The QRS0 was correlated with the extent of the Tl-201 perfusion defect (r = 0.79, p < 0.001), and the day 7 QRS score was correlated with Tc-99m pyrophosphate infarct size (r = 0.79, p < 0.005). CONCLUSIONS: The 32-point QRS score can provide useful immediate measurements of the ischemic risk region and subsequent infarct size.

Aged↗
PubMed1996

Optimized sampling and parameter estimation for quantification in whole body PET.

Whole-body positron emission tomography (PET) has recently emerged as an important imaging tool for cancer detection and staging. Initial applications of the technique have been primarily qualitative. One of the major reasons is the limits imposed by kinetically undersampled data over the whole body, as opposed to the standard method of continuous dynamic sampling in one body location. In this paper, a new estimation method using weighted nonlinear least squares (WNLS) for the first bed position and Bayesian regression (BR) for subsequent positions is proposed. A general criterion for designing optimal sampling schedules which maximizes the measurement information with multiple bed positions is developed. The overall approach is illustrated with the problem of estimating the metabolic rate of glucose (MRGLu) in tumors at different axial positions (image bed positions) in the body by using computer simulations and patient data. The results show that estimates of MRGLu using sparse data and the optimized Bayesian approach are comparable with those obtained by standard methods and fully sampled data. This study demonstrates the potential of the technique described for quantification where several bed positions have to be used to image all the regions of interest (ROI).

Abdominal Muscles↗
PubMed1996

Inhalation of hypertonic saline aerosol enhances mucociliary clearance in asthmatic and healthy subjects.

Hyperosmolarity of the airway surface liquid (ASL) has been proposed as the stimulus for hyperpnoea-induced asthma. We found previously that mucociliary clearance (MCC) was increased after isocapnic hyperventilation (ISH) with dry air, and we proposed that the increase related to transient hyperosmolarity of the ASL. We investigated the effect of increasing the osmolarity of the ASL on MCC, by administering an aerosol of concentrated salt solution. MCC was measured using 99mTc-sulphur colloid, gamma camera and computer analysis in 12 asthmatic and 10 healthy subjects on three separate days, involving administration of each of the following: 1) ultrasonically nebulized 14.4% saline; 2) ultrasonically nebulized 0.9% saline; and 3) no aerosol intervention (control). The (mean +/- SD) volume of nebulized 14.4% saline was 2.2 +/- 1.2 mL for asthmatics and 3.2 +/- 0.7 mL for healthy subjects. This volume was delivered over a period of 5.4 +/- 1.3 and 6.4 +/- 0.7 min for asthmatic and healthy subjects, respectively. The airway response to 14.4% saline was assessed on a separate visit and the fall in forced expiratory volume in one second (FEV1) was 22 +/- 4% in the asthmatic and 3 +/- 2% in the healthy subjects. Compared to the MCC with the 0.9% saline and control, the hypertonic aerosol increased MCC in both groups. In asthmatic subjects, MCC of the whole right lung in 1 h was 68 +/- 10% with 14.4% saline vs 44 +/- 14% with 0.9% saline and 39 +/- 13% with control. In healthy subjects, MCC of the whole right lung in 1 h was 53 +/- 12% with 14.4% saline vs 41 +/- 15% with 0.9% saline and 36 +/- 13% with control. We conclude that an increase in osmolarity of the airway surface liquid increases mucociliary clearance both in asthmatic and healthy subjects. These findings are in keeping with our previous suggestion that the increase in mucociliary clearance after isotonic hyperventilation with dry air is due to a transient hyperosmolarity of the airway surface liquid.

Administration, Inhalation↗
PubMed1977

An investigation into the psychological effects of hysterectomy.

The major aim of the present study was to determine whether women exposed to a hysterectomy procedure showed any greater evidence of postsurgery mood disorder than a cholecystectomy control group. In addition, the investigation also considered whether sterilization by hysterectomy resulted in more frequent mood disturbance than in tubal ligation where the uterus remains undisturbed. Fifty-five hysterectomy patients were compared with 38 cholecystectomy and 60 tubal ligation patients by means of the Profile of Mood States. Presurgery, 6-weeks postsurgery, and 3-months postsurgery measures were obtained. No evidence was found to support the view that the special psychological significance of the uterus results in greater postsurgery mood disturbance than occurs with a control procedure such a cholecystectomy. Neither did the results suggest that sterilization involving organ removal was psychologically more traumatic than where the sterilization procedure left the uterus undisturbed. The two significant group X occasion interactions implied that the groups differed in their pattern of responding to surgery with respect to the Tension-Anxiety and the Fatigue-Inertia variables.

Adult↗
PubMed1977

Recent changes in the emotional reactions of therapeutic aboriton applicants.

The emotional status of one hundred women applying for therapeutic abortions during 1967/68 was compared with that of 100 more recent applicants in 1975. The Minnesota Multiphasic Personality Inventory of the two groups reveals a significant reduction in psychopathology amongst the more recent applicants. This difference remains when group differences in age are controlled, and applies when married and single subgroups are considered separately. These results are interpreted as suggesting that the generally more liberal social atmosphere surrounding present-day abortions is reducing psychological stress among women undergoing this procedure.

Abortion, Therapeutic↗