Respiratory input impedance from 4 to 256 Hz in normals and chronic airflow obstruction: comparisons and correlations with spirometry.

Measurement of respiratory system input impedance (Zrs) by forced oscillation (FO) has generally been limited to frequencies less than or equal to 50 Hz, and correlations with spirometry have been variable. Using FO from 4 to 256 Hz in normals, Jackson and colleagues recently described a first acoustic antiresonance frequency (Far,1) at approximately 170 Hz. Using the same frequency range, we compared several Zrs spectral characteristics with spirometry in 12 chronic airflow obstruction (CAO) patients (range FEV1 0.

Effect of reduction of plasma triglycerides with gemfibrozil on high-density-lipoprotein-cholesterol concentrations.

The aim of this study was to test the hypothesis that the plasma triglyceride (TG) concentration must be reduced below approximately 0.85-1.13 mmol l-1 (75-100 mg/dl-1) in order to achieve a substantial increase in plasma high-density-lipoprotein-cholesterol (HDL-C) levels.

Parker B. Francis Lecture. Animal models of chronic airways injury.

Airways SCM is induced by a wide variety of noxious agents that perturb but do not kill the epithelial cells. Discharge of mucus soon after first exposure to a noxious agent is frequently observed, but discharge of mucus may or may not be followed by development of SCM. Treatment with steroidal and nonsteroidal antiinflammatory agents protects against development of SCM in some models, such as tobacco smoke-induced SCM, but not in others, such as enzyme-induced SCM.

A submucosal true vocal fold infusion needle.

This simple, inexpensive device for submucosal true vocal fold saline infusion into Reinke's space improves the diagnosis and treatment of small vocal cord lesions and is a useful addition to our microlaryngoscopy instrumentation.

New method for expressing F-wave data as conduction velocity.

A method for expressing F-wave data as a conduction velocity (normalized F-wave conduction velocity, NFCV) is described for the median, ulnar, peroneal, and posterior tibial nerves. Surface measurements routinely performed for calculation of motor conduction velocity (MCV) are used together with F-wave latency and a compensation factor (CF) to calculate a "velocity" easily comparable (normalized) to the MCV. Significant correlations between segmental "limb lengths" and whole 'extremity lengths" are shown.

L-tryptophan use and the eosinophilia-myalgia syndrome.

We present a case of the eosinophilia-myalgia syndrome in a patient taking large doses of L-tryptophan for sedation. He developed the now-classic findings of myalgias, skin changes, and marked eosinophilia. This syndrome was first recognized in late 1989, and epidemiologic studies have demonstrated an association of the clinical syndrome with ingestion of L-tryptophan.

Complications of care in a medical intensive care unit.

Objective: To determine the frequency and nature of complications of care in the medical intensive care unit (MICU).

Design: Prospective, observational study.

Setting: Seven-bed MICU in a teaching and referral VA hospital.

New Data on the Methohexital-Thiopental-Arrhythmia Issue.

Previous reports of a much greater incidence of arrhythmias with thiopental anesthesia for electroconvulsive therapy (ECT) compared to methohexital were reexamined and the possible role of hypercapnia reconsidered. Review of 50 treatments with each agent in 13 patients who had received each at our facility revealed only one brief episode of arrhythmia. The importance of postictal hyperventilation in preventing hypercapnia and associated arrhythmias was suggested.

Body image and comprehension of body part names.

The relation between awareness of body topology and auditory comprehension of body part names was studied in 22 aphasic subjects. Two nonverbal tasks--human figure drawing and placement of individual body parts in relation to a drawn face--were compared with two auditory tests of body part comprehension. The two nonverbal and the two verbal tasks were closely correlated with each other, but there was no relation involving either of the verbal tests with either of the nonverbal tests.

The nature of prolonged word search.

Two alternative hypotheses were considered concerning the process of prolonged search for an uncommon word in response to hearing its definition. One alternative is that a conscious retrieval effort brings the target progressively closer to threshold. The second is that the retrieval process is a random neural exploration outside of conscious control.

Stimulation SFEMG in myasthenia gravis.

The diagnostic usefulness of single-fiber electromyography (SFEMG) in the diagnosis of neuromuscular transmission disorders is well established. Increased jitter is one of the earliest indications of abnormality. In patients with severe weakness, tremor, or altered consciousness, performance of the study is difficult because of the degree of cooperation needed.

Creatine kinase elevation after neuroleptic treatment.

Two cases of asymptomatic elevation of creatine kinase levels after oral neuroleptic treatment are described. One patient was successfully challenged with a different neuroleptic. The authors discuss possible reasons for creatine kinase elevation.

Percutaneous cholecystostomy of an ectopic gallbladder.

Percutaneous cholecystostomy and drainage of a retrohepatic gallbladder were performed in a patient with sclerosing cholangitis. Correlative imaging using computed tomography, ultrasound, percutaneous transhepatic cholangiography, and sulfur colloid liver scan of this unusual anomaly are presented herein.

The dexamethasone suppression index: enhancement of DST diagnostic utility for depression by expressing serum cortisol as a function of serum dexamethasone.

The authors sought to determine whether the performance of the dexamethasone suppression test (DST) could be enhanced by expressing cortisol as a function of dexamethasone. Because cortisol concentration is a function of the reciprocal of dexamethasone concentration, this relationship was approximated by calculating the product of cortisol and dexamethasone as a dexamethasone suppression index. Preliminary assessment of test performance measures (sensitivity, specificity, and predictive power) showed that use of the dexamethasone suppression index was an improvement over the use of cortisol levels alone.

Category and modality specific dissociations in word comprehension and concurrent phonological dyslexia.

A 62-yr-old aphasic patient was found to have a marked auditory comprehension deficit for body parts, colors, numbers and letters in the face of excellent comprehension for all other word categories and virtually intact reading comprehension for all word categories, including those affected by the auditory dissociation. A severe impairment in the graphophonemic route for reading was also discovered. The case is discussed in the context of category-specific dissociations after brain injury and the possible mechanism for failures of body part comprehension.

Papillary muscle structure-function relations in the aging spontaneously hypertensive rat.

Isolated left ventricle papillary muscle mechanics and structure were studied in male spontaneously hypertensive (SHR) rats and two control groups of animals, the normotensive Wistar (NR) and the Wistar-Kyoto rat (WKY). Active tension and its first derivative (dT/dtmax) normalized for muscle cross-sectional area were increased in preparations from the SHR at all ages studied relative to control groups (P less than 0.01).

Verbal memory deficits associated with major affective disorders: a comparison of unipolar and bipolar patients.

The verbal learning and fluency of patients with unipolar and bipolar depression were compared to those of normal controls and patients with Huntington's disease. The data demonstrated that the recall and recognition performance of both groups of depressed patients were impaired relative to the performance of normal control subjects. The bipolar patients, however, were more impaired than the unipolar patients on both tasks (P less than 0.