Radiolabelling leukocytes with 99Tcm-stannous chloride colloid for the detection of inflammatory lesions.

Freshly prepared 99Tcm-stannous chloride colloid (99Tcm-SCC) was used to label human leukocytes. The radiolabelled leukocytes were then injected intravenously into rats bearing carrageenan-induced inflammation in their hindlimbs. Scintigraphic imaging (n = 3) and biodistribution studies (n = 4) 4 h post-injection were performed.

Pathogenesis and prognostic significance of conduction abnormalities after coronary bypass surgery.

Of 200 men who underwent isolated coronary bypass graft surgery, 40 (20%) developed new postoperative, persistent conduction abnormalities. The pathogenesis of conduction abnormalities was examined by relating their presence to that of significant proximal left coronary disease before surgery, and to various intraoperative factors that included indices of myocardial preservation and revascularization. Proximal left coronary disease was observed in 92 (46%) of 200 patients, of whom 27 (29%) developed conduction abnormalities.

Elucidating the mechanisms of atrial flutter cycle length variability using power spectral analysis techniques.

Background: The mechanism of the small beat-to-beat variations in cycle length of atrial flutter in humans has not been fully explained. We investigated the beat-to-beat control of atrial flutter cycle length using time and frequency analysis techniques.

Methods And Results: Mean, SD, and power spectra of atrial cycle lengths were calculated from atrial recordings in 28 patients with type I atrial flutter.

Limitations of tachycardia confirmation and rate classification algorithms in a third-generation implantable cardioverter defibrillator.

Newer ICDs provide antitachycardia (ATP) and bradycardia pacing and cardioversion and defibrillation shocks based on sensed interval criteria. The objectives of this investigation were to determine the algorithm related errors in tachycardia confirmation and rate classification that occurred in patients with a third-generation, noncommitted, tiered ICD therapy. Forty-three consecutive patients with the Guardian ATP 4210 ICD, which uses an X out of Y sensed interval counting algorithm for tachycardia detection, confirmation, and classification were studied.

Prediction of prostatic obstruction with a combination of isometric detrusor contraction pressure and maximum urinary flow rate.

Objectives: Because isometric detrusor contraction pressure (Piso) increases with outlet obstruction and maximum urinary flow rate (Qmax) tends to decrease with obstruction, we hypothesize that specific criteria consisting of a combination of high Piso and low Qmax may be able to differentiate obstructive from nonobstructive voiding dysfunction better than either parameter alone.

Methods: Two hundred five men with lower urinary tract symptoms underwent uroflowmetry and videourodynamics, including cystometry, continuous outlet occlusion test, and micturitional urethral pressure profilometry. Combined threshold values of Qmax of less than 12 mL/s and Piso of 100 cm H2O or greater were used to predict obstruction, whereas threshold values of Qmax of at least 12 mL/s and Piso less than 100 cm H2O were used to predict nonobstruction.

Evaluation of a laboratory critical limit (alert value) policy for hypercalcemia.

Objective: To evaluate a laboratory critical limit policy for hypercalcemia requiring the laboratory to notify the physician for any serum calcium level higher than 2.99 mmol/L (12.0 mg/dL).

Occupationally induced airways obstruction.

The studies reviewed in this article indicate the association of occupational exposure to a variety of organic and inorganic dusts and various gases and fumes with chronic bronchitis and decrements of FEV1. Usually an obstructive pattern was noted, although in some occupations a similar decrement in FVC was noted. The effect of smoking on chronic bronchitis, respiratory symptoms, and FEV1 was usually additive, although workers exposed to cotton dust in one study demonstrated an interaction between exposure and smoking, as did a study of a general population sample.

Accuracy of motor responses in subjects with and without control of antagonist muscle.

1. The aim of this study was to investigate the role of the antagonist muscle in determining the accuracy of fast, single-joint motor responses to a target. We recently found that C5/C6 tetraplegic subjects, who lacked voluntary control of their triceps muscle, were less accurate than control subjects in producing fast flexion movements to a target.

The association of sudden unexpected infant death with obstructive sleep apnea.

We studied the relationship of sudden unexpected infant death/apparent life-threatening events (ALTE) to obstructive sleep apnea (OSA) in 74 index probands who had either sleep-laboratory-confirmed OSA or a clinical diagnosis of OSA requiring treatment, 62 matched control probands, and their spouses and first- and second-degree relatives. Sleep was monitored in the home overnight, and OSA was defined by respiratory disturbance indices (number of apneas/hypopneas per hour of sleep) corrected for normal increases with age. Information on sudden unexpected infant death/ALTE was obtained by questionnaire and was corroborated.

Detrusor contractility and compliance characteristics in adult male patients with obstructive and nonobstructive voiding dysfunction.

Purpose: To understand better the contractility and compliance characteristics of the detrusor in patients with varying degrees of outlet obstruction, we analyzed urodynamic studies in elderly men with obstructive and nonobstructive voiding dysfunction.

Materials And Methods: All patients were evaluated with video urodynamics, including cystometry, isometric tests, voiding profilometry and post-void residual measurement. Bladder compliance, detrusor contractility, detrusor reserve, detrusor instability and the severity of outlet obstruction were determined in each patient.

Micturitional urethral pressure profilometry.

The technique of micturitional urethral pressure profilometry using a trilumen catheter provides a method of assessing the dynamic behavior of the lower urinary tract during voiding. This method of evaluation is simple to perform, highly reproducible, accurate, and clinically useful not only in diagnosing the presence of outlet obstruction, but also in identifying its location and assessing its severity. The rationale for the use of this technique, the interpretation of the results, and various pressure profile configurations are discussed.

Comparative efficacy of intravenous ibutilide versus procainamide for enhancing termination of atrial flutter by atrial overdrive pacing.

This study compares the influence of intravenous ibutilide, a class III antiarrhythmic agent, with procainamide, a class IA antiarrhythmic agent, and with placebo on its ability to terminate atrial flutter using rapid atrial pacing. Fifty-nine episodes of atrial flutter in 54 patients who failed to terminate with an intravenous infusion of ibutilide, procainamide, or placebo alone underwent attempts at pacing termination using a standard protocol of burst atrial overdrive pacing. Atrial flutter cycle length and atrial monophasic action potential duration recorded from the right atrium during atrial flutter were measured at baseline and following infusion of ibutilide, procainamide, or placebo.

Effect of physician gender on the prescription of estrogen replacement therapy.

Objective: To determine if women cared for by female physicians are more likely to receive postmenopausal estrogen replacement therapy than women cared for by male physicians.

Design: Case-control study with follow-up telephone survey.

Setting: An outpatient practice at an urban teaching hospital in Boston, Massachusetts.

Pharmacologic alterations in human type I atrial flutter cycle length and monophasic action potential duration. Evidence of a fully excitable gap in the reentrant circuit.

Objectives: This study compared the effect of changes in action potential duration versus conduction velocity on atrial flutter cycle length to determine whether there is a fully or partially excitable gap in atrial flutter.

Background: In an excitable gap reentrant circuit, cycle length is proportional to conduction velocity. Action potential duration is not a direct determinant of cycle length when the gap is fully excitable.

Detrusor internal and external work in relation to passive urethral resistance in a canine model of the lower urinary tract.

This study was conducted to evaluate whether passive urethral resistance, detrusor internal work, and detrusor external work are independent measures of the voiding process. Passive urethral resistance, detrusor internal work, detrusor external work, and detrusor total work of 5 canines were determined under nonobstructive and obstructive outlet conditions. All urodynamic analyses were performed on a surgically exposed urinary tract.

Combinations of maximum urinary flow rate and American Urological Association symptom index that are more specific for identifying obstructive and non-obstructive prostatism.

Uroflowmetry and the American Urological Association symptom index (AUASI) are often used clinically to evaluate patients with benign prostatic hyperplasia (BPH). Since results from these tests may be used to determine a treatment course, including surgical intervention, we investigated if specific combinations of uroflowmetry and AUASI parameters could better predict urodynamically confirmed prostatic obstruction. Data from 134 men (mean age: 67.

Assessment and modeling of the physical components of human corporovenous function.

To understand and quantify specific causes of venoocclusive dysfunction, an analog model of penile hemodynamics, including a mechanism of flow limitation by subtunical veins, was developed and a detailed analytic study was conducted in patients with erectile dysfunction. Computer simulations for steady-state and transient intracavernosal conditions were carried out to study graded changes in cavernosal smooth muscle tone, subtunical venular resistance, and cavernosal and tunical compliances. The model predicted a steady-state cavernosal pressure (Pca)-infusion flow relationship with two phases: an initial phase characterized by a gradual slope up to a critical flow and a second phase characterized by a much steeper slope after limitation of subtunical venular flow.

Dehydration. Evaluation and management in older adults. Council on Scientific Affairs, American Medical Association.

Objective: To review published literature regarding dehydration in older individuals and formulate a consensus on the evaluation and treatment of this unrecognized cause of hospitalizations, morbidity, and mortality.

Data Sources And Study Selection: The literature concerning dehydration in the elderly population from MEDLINE was reviewed from 1976 through 1995. Search terms included dehydration, elderly, evaluation, hospitalization, and treatment.

Caudate, putamen, and globus pallidus volume in schizophrenia: a quantitative MRI study.

Basal ganglia structures have been reported to be abnormal in schizophrenia. However, while component structures of the basal ganglia are functionally differentiated, there have been no evaluations of their separate magnetic resonance imaging (MRI) volumes with small voxel (1.5 mm3) spoiled gradient-recalled acquisition in steady state techniques and multi-plane assessments.

Continuous occlusion test to determine detrusor contractile performance.

Purpose: A study was conducted to determine the merits of the continuous occlusion test as a method of detrusor contractility assessment by comparing it with other stop tests and with contractility derived from pressure-flow analysis.

Materials And Methods: The continuous occlusion test was performed in elderly men by occluding the bladder outlet before the onset of a detrusor contraction and it was repeated to assess reproducibility. The magnitude of the isovolumetric contraction, maximum slope of the detrusor contraction, and duration of detrusor activation were determined.

Heparin causes platelet dysfunction and induces fibrinolysis before cardiopulmonary bypass.

Background: Platelet dysfunction and increased fibrinolysis are the most important etiologic factors in the hemostatic defect observed following the institution of cardiopulmonary bypass. This study examined the effects of heparin per se, administered before the institution of cardiopulmonary bypass, on platelet function and fibrinolysis.

Methods: Sampling was performed in 55 patients undergoing cardiac operations before and 5 minutes after the routine administration of heparin, before the institution of cardiopulmonary bypass.

The usefulness of calibration verification and linearity surveys in predicting acceptable performance in graded proficiency tests.

Objective: To assess the association between performance on graded chemistry surveys and evaluation of linearity and calibration in Linearity surveys.

Design: Data from Linearity Surveys (LN series) and from routine comprehensive College of American Pathologists chemistry surveys (all series) were used to evaluate the hypothesis that laboratories with nonlinear or univerified calibration would have a greater likelihood of unacceptable performance on comprehensive chemistry surveys.

Results: This study found that acceptable calibration verification evaluation is significantly related to acceptable rates for most analytes, including albumin, calcium, chloride, glucose, iron, magnesium, sodium, total bilirubin, uric acid, high-density lipoprotein cholesterol, triglycerides, alkaline phosphatase, alanine and aspartate aminotransferase, digoxin, gentamicin, phenobarbital, procainamide, and thyroxine.

Significance of low serum alkaline phosphatase activity in a predominantly adult male population.

The causes for low serum alkaline phosphatase (ALP) activity (reference range 30-115 U/L) in a large Veterans Medical Center were reviewed. Of 69,864 ALP determinations made over a 4-year period, 130 were low (< 30 U/L, 0.19%), representing 88 individual patients.