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Biomedical subjects

D L Kaiser

Publications and source records attributed to D L Kaiser.

At least 37 records · Page 2Linked to original sources
PubMed1988

A comprehensive analysis of myocardial infarction due to left circumflex artery occlusion: comparison with infarction due to right coronary artery and left anterior descending artery occlusion.

Forty consecutive patients with creatine kinase-MB confirmed myocardial infarction due to circumflex artery occlusion (Group 1) were prospectively evaluated and compared with 107 patients with infarction due to right coronary artery occlusion (Group 2) and 94 with left anterior descending artery occlusion (Group 3). All 241 patients underwent exercise thallium-201 scintigraphy, radionuclide ventriculography, 24 h Holter electrocardiographic (ECG) monitoring and coronary arteriography before hospital discharge and were followed up for 39 +/- 18 months. There were no significant differences among the three infarct groups in age, gender, number of risk factors, prevalence and type of prior infarction, Norris index, Killip class and frequency of in-hospital complications. Acute ST segment elevation was present in only 48% of patients in Group 1 versus 71 and 72% in Groups 2 and 3, respectively (p = 0.012), and 38% of patients with a circumflex artery-related infarct had no significant ST changes (that is, elevation or depression) on admission (versus 21 and 20% for patients in Groups 2 and 3, respectively) (p = 0.001). Abnormal R waves in lead V1 were more common in Group 1 than in Group 2 (p less than 0.003) as was ST elevation in leads I, aVL and V4 to V6 (p less than or equal to 0.048). These differences in ECG findings between Group 1 and 2 patients correlated with a significantly higher prevalence of posterior and lateral wall asynergy in the group with a circumflex artery-related infarct. Infarct size based on peak creatine kinase levels and multiple radionuclide variables was intermediate in Group 1 compared with that in Group 2 (smallest) and Group 3 (largest). During long-term follow-up, the probability of recurrent cardiac events was similar in the three infarct groups. When patients with a circumflex artery-related infarct were stratified according to the presence or absence of abnormal R waves in lead V1 or V2, the abnormal R wave group had more admission ST elevation (p = 0.025), a larger infarct (p less than 0.05) and more extensive coronary artery disease (p = 0.027). In fact, all patients with a circumflex artery-related infarct and an abnormal R wave in lead V1 had multivessel disease. An abnormal R wave in lead V1 had a 96% specificity for circumflex versus right coronary artery-related infarction but a sensitivity of only 21%. Discriminate function analysis of all admission historical and ECG variables identified inferior and lateral ST elevation as independent predictors of circumflex artery-related infarction...

Angiography↗
PubMed1988

Two randomized controlled trials of virucidal nasal tissues in the prevention of natural upper respiratory infections.

Two six-month randomized, controlled double-blind trials of the efficacy of virucidal nasal tissues in the prevention of natural colds were conducted in Charlottesville, Virginia, between 1983 and 1986. Tissues impregnated with malic and citric acids and sodium lauryl sulfate were used in both trials. Placebo tissues contained saccharin in the first trial and a mixture including succinic acid in the second. A total of 186 families were evaluable after completion of trial I, and 98 families were evaluable in trial II. The antiviral tissues were associated with 14 and 5% relative reductions in the overall rate of colds in the first and second trials, respectively. In the first study, this appeared to be due to an appropriate fall in secondary illnesses with a relative reduction in the ratio of secondary to primary illnesses of 32%. In trial II, however, the small and statistically insignificant reduction was primarily due to a drop in the rate of primary illness (which cannot be attributed to tissue efficacy), and the ratio of secondary to primary illness was actually 5% higher in the group with active tissues than in the placebo group. We conclude that when rigorously used in a study protocol, virucidal tissues may offer a modest reduction of secondary colds in the home, but for reasons currently unknown, do not have a major effect on the overall rate of colds.

Antiviral Agents↗
PubMed1988

Ineffectiveness of oral terfenadine in natural colds: evidence against histamine as a mediator of common cold symptoms.

The role of histamine in the pathogenesis of infectious rhinitis is unclear, as is the efficacy of antihistaminic drugs in the treatment of the common cold. This study evaluated the short-term efficacy of oral terfenadine (Seldane) in the treatment of the common cold. Over a 5-week period, the authors recruited 250 adults who had developed cold symptoms within 6 to 48 hours prior to enrollment. Volunteers had a primary complaint of runny or stuffy nose; at least one other respiratory symptom; no fever or exudative pharyngitis; and no history of atopy, sinusitis, or use of cold preparations within 1 week of enrollment. Out of the eligible subjects, 126 were randomly assigned terfenadine (60 mg), and 124 received placebo. Volunteers self-administered either terfenadine or placebo twice a day on Days 1, 2 and 3, and a final dose on the morning of Day 4. They also recorded the severity of their clinical symptoms (runny nose, sniffles, sneezing, postnasal drip, cough and sore throat) on symptom cards. Both groups reported similar severity scores throughout the treatment period. Average symptom burdens declined at almost identical rates for both groups. Terfenadine was well tolerated and had a low incidence of side effects. According to subject evaluation, terfenadine was no more effective than placebo. The mean +/- SD score of global efficacy was 2.2 +/- 1.1 in the terfenadine group and 2.1 +/- 1.3 in the placebo group (P = NS). Slightly fewer terfenadine recipients (41%) than placebo recipients (48%) said they would use the study medication again for treating cold symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Intranasal recombinant alfa-2b interferon treatment of naturally occurring common colds.

In a double-blind, placebo-controlled study, patients with naturally occurring common colds of less than or equal to 48 h duration were randomly assigned to receive nasal sprays of recombinant alfa-2b interferon at 10 or 20 MU/day or placebo four times per day for 5 days. The 10-MU (n = 74), 20-MU (n = 74), and placebo (n = 72) groups had comparable frequencies of documented rhinovirus colds (50 to 65%) and mean durations of pretreatment symptoms (26 to 27 h). The median duration of colds tended to be longer in the 20-MU group (10 days) than the 10-MU group (8 days) or placebo group (8 days) (P = 0.06). In those with proven rhinovirus colds treated within 24 h, the median duration was significantly longer in the 20-MU group (9 days) than in the placebo group (6 days). No differences favoring interferon treatment were found in respiratory symptom scores or resolution of specific symptoms. On days 5 and 7, nasal washings from compliant subjects with proven rhinovirus colds yielded rhinoviruses more often in placebo (47 and 48%, respectively) than in interferon (15 and 16%, respectively) recipients (P less than 0.02), but no differences in new respiratory illness occurrence were observed in household contacts. Interferon recipients had significantly higher frequencies of blood in nasal mucus (16 to 18%) than did placebo recipients (4%) during treatment. Antibiotics for presumed secondary infections were given more often in the 20-MU group (11%) than in the placebo group (0%) (P less than 0.01). Nasal sprays of recombinant alfa-2b interferon were not an effective treatment for natural colds and were associated with toxicity.

Administration, Intranasal↗
PubMed1988

Comparative assessments of objective peak-detection algorithms. II. Studies in men.

The performances of eight currently available computerized pulse-detection algorithms were compared on signal-free noise and physiological luteinizing hormone (LH) time series. Signal-free noise was made to vary from 4 to 36% for Gaussian and empirical distributions. Physiological LH data were obtained by immunoassay of blood samples withdrawn every 5 min for 24 h in 8 healthy men, so that the data sets could be emended to simulate varying sampling intensities. Whenever possible, programs were tested at a presumptive 1% false-positive rate. In relation to signal-free noise, the Santen and Bardin program and its modification manifested elevated false-positive rates when the intraseries coefficients of variation increased. The Regional Dual-Threshold program yielded a 1% false-positive rate except on simulated series with high variance. The Cluster and Detect programs both approximated a 1% false-positive rate and the Ultra program approximated a 2.3% false-positive rate throughout the entire range of variance tested. In regard to physiological LH data, all algorithms disclosed a significant impact of sampling intensity on estimates of LH pulse frequency. Sampling-intensity dependent estimates of LH peak frequency by three of the eight programs (Ultra, Cluster, and Detect) were statistically indistinguishable from each other but distinct from the five other programs tested. Furthermore, when judged in relation to their ability to identify individual peaks, the three congruent programs were minimally distinguishable (McNemar's test). Rather, these programs identified the same particular peaks (as defined by concordance of peak maxima) at least 72% of the time.

Adult↗
PubMed1988

Clinical identification of nondiabetic renal disease in diabetic patients with type I and type II disease presenting with renal dysfunction.

A retrospective study was done on 109 diabetic patients who had renal biopsies during 1974-1984 to determine factors identifying nondiabetic renal disease in patients with diabetes mellitus presenting with renal dysfunction. Six of 49 (12%) patients with type I and 17 of 60 (28%) with type II diabetes mellitus had other renal diseases, with or without diabetic glomerulosclerosis. Multivariate predictors of other renal disease in type I diabetes mellitus were duration less than 5 years (p less than 0.001), absence of proteinuria (p less than 0.001), and absence of neuropathy (p less than 0.05). In type II diabetes mellitus these were late age of onset (p less than 0.001), absence of neuropathy (p less than 0.05), and Caucasian race (p less than 0.005). Some patients with other diseases appeared to respond to therapy directed at their nondiabetic glomerulosclerosis disease. We emphasize the need to distinguish between the subgroup of diabetic patients with nondiabetic renal disease from the majority who have diabetic glomerulosclerosis alone. The latter group should be spared the discomforts, risks, and costs of a renal biopsy.

Adolescent↗
PubMed1988

Peripheral insulin release after pancreatic resection: the effect of decreased beta-cell mass with systemic or portal drainage.

Surgical alteration of the pancreas can result in several anatomic alterations which may affect insulin release. We evaluated the effects of resection, systemic drainage, and autotransplantation of the canine pancreas on peripheral insulin levels and glucose disposal as measured by iv glucose tolerance tests (IVGTT) and a steady state hyperglycemic challenge (clamp). Proximal pancreatectomy (PPx) with reduced beta-cell mass and intact portal drainage resulted in a modestly elevated fasting glucose level and increased integrated glucose response to IVGTT. Compared to preoperative normals, basal insulin was unchanged from preoperative controls; however, peak insulin and integrated insulin response to IVGTT were decreased in PPx animals. Splenocaval drainage or autotransplantation of the distal pancreas resulted in normalization of the severely altered insulin response and fasting glucose levels. K values were significantly reduced after all three procedures. Clamp studies confirmed the basal glucose and insulin findings of the IVGTT. During the clamp, PPx animals had peripheral insulin values approximately 50% of normal controls, while autotransplantation and splenocaval drainage animals had insulin values that approximate normal controls. All three postsurgical groups had blunted insulin levels during stable hyperglycemia. Glucose utilization rates were severely decreased in all three groups. Reduction of beta-cell mass with intact portal drainage resulted in reduced insulin response to glucose challenge by either IVGTT or clamp. Systemic drainage of this same reduced beta-cell mass resulted in peripheral insulin levels comparable to normal controls. Denervation (autotransplantation) had little additive effect. All three groups demonstrated severely decreased rates of glucose disappearance as measured by both IVGTT and clamp studies. Therefore, reduction in beta-cell mass, drained systemically or portally, results in altered glucose disposal regardless of the peripheral insulin levels.

Animals↗
PubMed1988

The effect of hyperthermia on radiation-induced carcinogenesis.

Ten groups of mice were exposed to either a single (30 Gy) or multiple (six fractions of 6 Gy) X-ray doses to the leg. Eight of these groups had the irradiated leg made hyperthermic for 45 min immediately following the X irradiation to temperatures of 37 to 43 degrees C. Eight control groups had their legs made hyperthermic with a single exposure or six exposures to heat as the only treatment. In mice exposed to radiation only, the postexposure subcutaneous temperature was 36.0 +/- 1.1 degrees C. Hyperthermia alone was not carcinogenic. At none of the hyperthermic temperatures was the incidence of tumors in the treated leg different from that induced by X rays alone. The incidence of tumors developing in anatomic sites other than the treated leg was decreased in mice where the leg was exposed to hyperthermia compared to mice where the leg was irradiated. A systemic effect of local hyperthermia is suggested to account for this observation. In mice given single X-ray doses and hyperthermia, temperatures of 37, 39, or 41 degrees C did not influence radiation damage as measured by the acute skin reactions. A hyperthermic temperature of 43 degrees C potentiated the acute radiation reaction (thermal enhancement factor 1.1). In the group subjected to hyperthermic temperatures of 37 or 39 degrees C and X rays given in six fractions, the skin reaction was no different from that of the group receiving X rays alone. Hyperthermic temperatures of 41 and 43 degrees C resulted in a thermal enhancement of 1.16 and 1.36 for the acute skin reactions. From Day 50 to Day 600 after treatment, the skin reactions showed regular fluctuations with a 150-day periodicity. Following a fractionated schedule of combined hyperthermia and X rays, late damage to the leg was less than that following X irradiation alone. Mice subjected to X rays and hyperthermic temperatures of 41 and 43 degrees C had a lower median survival time than the mice treated with hyperthermia alone. This effect was not associated with tumor incidence.

Animals↗
PubMed1988

Correlation of parameters of urinary excretion with serum osmolality among patients with psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome).

Nine patients (seven men and two women, mean age 36.3 +/- SD 6.7 years), six of whom had schizophrenic disorders, two of whom had bipolar disorder (manic-depressive illness), and one of whom had schizoaffective disorder, manifested psychosis, intermittent hyponatremia, and polydipsia (PIP syndrome). Their stable pattern of hyposthenuria allowed us to predict 24-hr urinary volume on the basis of estimated daily urinary creatinine and early morning urinary creatinine concentration. Lithium and carbamazepine (Tegretol) had little, if any, effect on polyuria. Correlations of parameters of urinary excretion with serum osmolality among our nine PIP patients failed to implicate water consumption as the exclusive cause of serum hypoosmolality and attendant complications usually ascribed to "water toxicity" in the PIP syndrome. Discussed, also, is the overlap of the clinical and laboratory features of the PIP syndrome with the clinical and laboratory features of both diabetes insipidus and the syndrome of inappropriate antidiuresis.

Adult↗
PubMed1987

Pathologic significance of nephromegaly in pediatric disease.

Ultrasonic renal volume and length measurements are easily performed in pediatric patients. Increases in volume over the normal level provide a potentially attractive method of assessing the severity and progression or regression of renal diseases. However, an analysis of data on 59 children with clinical renal disease and nephromegaly did not demonstrate any correlation with severity of the disease. We conclude that increases in renal length and volume in pediatric patients may indicate the presence of disease but not its severity.

Adolescent↗
PubMed1987

Actions of calcium ions and a calcium-influx blocker on basal and TRH- and GnRH-stimulated hormone release in patients with pituitary adenomas.

We investigated the influence of calcium ions on the secretion of anterior pituitary hormones basally and in response to exogenous hypothalamic releasing factors in 6 men with pituitary tumors. To this end, concentrations of LH, FSH, TSH, growth hormone and prolactin were measured in blood collected at 10-min intervals basally and during a continuous infusion of combined TRH (2 micrograms/min) and GnRH (1 microgram/min). Study sessions were randomized to iv saline, calcium, or diltiazem infusions or oral diltiazem administration. Our results indicate that in contrast to responses in normal men, iv calcium injections do not suppress circulating prolactin concentrations in patients with prolactin-secreting pituitary tumors. Moreover, neither oral diltiazem administration for one week nor acute iv diltiazem infusion suppressed the hyperprolactinemia of tumor patients. However, there were significant effects of drug and calcium treatments on serum concentrations of FSH, GH and testosterone, but not LH or TSH. Moreover, during GnRH-TRH stimulation, there were significant differences in LH, TSH, and testosterone responses in tumor patients compared to normal men. In summary, iv calcium infusion was associated with invariant basal release of anterior pituitary tumoral hormones in patients with pituitary adenomas. However, there were significant differences in the GnRH/TRH-stimulated release of certain anterior pituitary hormones in tumor patients compared to normal men in response to iv calcium and the calcium-channel antagonist, diltiazem.

Adenoma↗
PubMed1987

Utility of the 24-hour delay hysterosalpingogram film.

Controversy exists regarding the ideal contrast media for hysterosalpingography. A unique property of oil-base contrast media is the availability of a 24-hour delay radiograph for further assessment of tubal patency and adhesions. A review was undertaken of the delay films in 131 cases performed by use of oil-base contrast media with subsequent surgical confirmation of pelvic findings. A 97% predictive accuracy was achieved with regard to distal obstruction and a 79% accuracy with regard to pelvic adhesions. Objective criteria for the evaluation of 24-hour delay hysterogram films were developed and are illustrated.

Contrast Media↗
PubMed1987

Acute non-Q wave myocardial infarction associated with early ST segment elevation: evidence for spontaneous coronary reperfusion and implications for thrombolytic trials.

The clinical significance of early ST segment elevation in patients with non-Q wave infarction is unknown. Therefore, 150 consecutive patients with creatine kinase isoenzyme-confirmed acute uncomplicated myocardial infarction who had ST segment elevation of 1 mm or more in at least two contiguous leads on the admission electrocardiogram were analyzed. None received thrombolytic therapy or acute coronary angioplasty. Predischarge angiography, radionuclide ventriculography and exercise thallium-201 scintigraphy were performed 10 +/- 3 days after myocardial infarction. Based on serial electrocardiograms (on days 1, 2, 3 and 10), all 150 infarcts were classified as Q wave (n = 115 [77%]) or non-Q wave (n = 35 [23%]). Although patients with Q wave infarction exhibited greater ST elevation, the amount observed in the non-Q wave group was appreciable, as reflected by the number of leads with ST elevation (3.8 +/- 1.8 versus 3.1 +/- 1.2, p = 0.007) and the sum of the ST elevation (9.6 +/- 7.4 versus 6.2 +/- 6.2 mm, p = 0.016). When compared with the Q wave group, patients with non-Q wave infarction had a shorter time to peak creatine kinase (23.0 +/- 9.1 versus 15.8 +/- 7.9 hours, p = 0.0001), a higher infarct vessel patency rate (24 versus 57%, p = 0.001), lower peak creatine kinase values based on 4 hour sampling (1,372 +/- 964 versus 664 +/- 924 IU/liter, p = 0.0002) and a higher left ventricular ejection fraction (46 +/- 12% versus 54 +/- 9%, p = 0.0003).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1987

Exercise-induced ST segment elevation 2 weeks after uncomplicated myocardial infarction: contributing factors and prognostic significance.

To define the prevalence and clinical significance of exercise-induced ST segment elevation during predischarge treadmill testing after uncomplicated acute myocardial infarction confirmed by serum MB creatine kinase (CK) activity, 241 consecutive patients were prospectively investigated with quantitative exercise thallium-201 scintigraphy, rest radionuclide ventriculography and coronary angiography at 10 +/- 3 days. All patients received customary care, and in none was thrombolytic therapy or emergency coronary angioplasty employed. Eighty-two patients (34%) had exercise-induced ST segment elevation of greater than or equal to 1 mm above rest baseline. These patients were similar to the 159 patients without this finding with respect to history of prior infarction, the Norris coronary prognostic index, exercise duration, metabolic equivalents (METs) achieved and peak heart rate-blood pressure product. The frequency of inducible myocardial ischemia and extent of angiographic coronary disease was also comparable in the two groups. Findings associated with larger infarct size and transmural extent of infarction were more common in patients with exercise-induced ST segment elevation than in those without, including higher peak CK values (1,235 +/- 1,037 versus 942 +/- 915 mumol/min per liter, p less than 0.026), lower left ventricular ejection fraction (43 +/- 12 versus 51 +/- 10%, p less than 0.001), a higher prevalence of pathologic Q waves in greater than or equal to 2 contiguous infarct-related leads (80 versus 55%, p less than 0.001), more persistent thallium-201 defects (2.2 +/- 1.1 versus 1.4 +/- 1.1, p less than 0.001), abnormally increased lung uptake of thallium (33 versus 18%, p less than 0.01) and a greater number of akinetic or dyskinetic segments (3.2 +/- 2.5 versus 1.4 +/- 1.9, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Angiography↗
PubMed1987

Relation between amiodarone and desethylamiodarone plasma concentrations and electrophysiologic effects, efficacy and toxicity.

Because the value of monitoring amiodarone plasma concentrations remains undefined, this study was performed to evaluate its role during the management of patients receiving amiodarone. The early electrophysiologic effects of amiodarone were assessed in 40 consecutive patients with coronary artery disease and sustained ventricular tachycardia or fibrillation who underwent electrophysiologic studies and measurement of amiodarone plasma concentration before and 29 +/- 15 (mean +/- SD) days after initiation of therapy. Amiodarone and desethylamiodarone plasma levels did not correlate with changes in either sinus cycle length, QTc interval, ventricular effective refractory period, AH and HV intervals or ventricular tachycardia cycle length. Amiodarone and desethylamiodarone plasma concentrations and the effects of the drug on conduction intervals or right ventricular effective refractory periods were not related to suppression of arrhythmia induction by ventricular stimulation after 1 month of therapy. The relation between amiodarone plasma concentrations and both toxicity and efficacy during long-term therapy were prospectively assessed in a larger series of 114 consecutive patients with either symptomatic supraventricular or ventricular arrhythmias who were followed up on long-term amiodarone therapy for 26 +/- 15 months. Sixty-three patients (55%) had one or more adverse effects attributed to amiodarone. By life-table analysis, 40, 69 and 80% of patients had experienced an adverse reaction after 1, 2 and 3 years of therapy, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1987

T-cells and macrophages in rapidly progressive glomerulonephritis: clinicopathologic correlations.

We phenotyped with monoclonal antibodies (MAb) the cellular infiltrates in kidneys of patients with rapidly progressive glomerulonephritis (RPGN) responsive (R) or nonresponsive (NR) to pulse methylprednisolone therapy (PM)-eight anti-GBM, six no immune deposits, three immune complex, two vasculitis, and one proliferative GN. There were glomerular, periglomerular, crescentic, and interstitial T and T-cell subsets. Few interstitial and no glomerular B and NK cells were observed. TH cells were much more common than TS. Phenotypes were quantitatively evaluated in 221 nephritic and 32 control glomeruli. T and/or TH cells were positively correlated with M phi, r = 0.30 to 0.74, P less than 0.05 to 0.0005. Although differences in phenotypes were observed, these differences were insufficient to distinguish between subtypes. Analysis of R and NR revealed no relationship to percent crescents, entry serum creatinine, oliguria, or need for dialysis. NR was related to presence of anti-GBM disease, P = 0.001, as was ability to stop dialysis, 0 of 7 GBM versus 9 of 10 other, P less than 0.001. Mild infiltrates of lymphocytes and M phi correlated with R, P less than or equal to 0.02. R had fewer numbers of TH and M phi in glomeruli, P = 0.0001, in crescents, P less than 0.02, and total TH and M phi compared to NR, P less than 0.001. Crescentic and total TH/S ratios were lower in NR than R, P less than 0.05. These findings demonstrate that components of the cell-mediated immune (CMI) system are present by MAb analysis, that subtypes cannot be differentiated by CMI constitution, and R to PM is related to intensity and composition of CMI involvement. Independence of the CMI system relative to anti-GBM disease remains to be clarified.

Antibodies, Monoclonal↗
PubMed1987

A measurement of the efficacy of nosocomial infection control using the 95 per cent confidence interval for infection rates.

From 1981 through 1985, the authors studied the changes in monthly nosocomial infection rates at the University of Virginia Hospital in Charlottesville, Virginia using the 95% confidence interval for infection rates as a marker of the efficacy of infection control activities. For a 99-month baseline period, monthly infection rates were calculated and the 95% confidence interval was established. In the 60 study months, each monthly rate was compared with the 95% confidence interval for that particular month. At the end of each study year, the monthly infection rates were incorporated into the existing confidence interval. Of 60 monthly rates during the study period, 30 were below the confidence interval (p less than 0.00001), two were above the confidence interval (p = 0.23), and 28 were within the confidence interval. Since there was no reduction in surveillance activity, patient case-mix index, or laboratory sensitivity for organism recovery, these results suggest that monthly nosocomial infection rates at this hospital have decreased when compared with the baseline period. The use of the 95% confidence interval may provide a measure of the efficacy of infection control activities, suggest temporal intervals requiring more intensive infection surveillance, and provide a method for examining the variability in monthly infection rates.

Cross Infection↗