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Biomedical subjects

T Roth

Publications and source records attributed to T Roth.

At least 127 records · Page 7Linked to original sources
PubMed1994

Sedative, memory, and performance effects of hypnotics.

The sedative, amnestic, and performance disruptive effects of benzodiazepine (Bz) receptor selective and non-selective hypnotics were studied in 23 healthy, normal subjects, aged 26.8 +/- 1.0 years. Triazolam (0.25 and 0.50 mg), zolpidem (10 and 20 mg) and placebo were administered, double-blind, at bedtime in a repeated measures design. During an awakening 90 min later (at approximate peak concentration of each drug) a 30-min performance battery which included memory, vigilance, and psychomotor tasks was completed. Each drug and dose impaired memory (both immediate and delayed), vigilance, and psychomotor performance relative to placebo. Among active drugs impairment was greatest with zolpidem 20 mg, next triazolam 0.50 mg, then zolpidem 10 mg, and finally triazolam 0.25 mg. Next morning delayed recall was also impaired by all drugs and doses (i.e. anterograde amnesia). The amnestic and performance-disruptive effects paralleled the relative hypnotic effects of the drugs and doses. No receptor selectivity in these pharmacodynamic effects was observed.

Adult↗
PubMed1994

Experimental sleep fragmentation.

Thirty-six healthy young men and women (age range 21-35 years) were studied in an experimental model of sleep fragmentation. On 2 nights sleep was disrupted by presenting tones to produce brief electroencephalogram (EEG) arousals (without shortening sleep time) and daytime function was assessed the following day with the Multiple Sleep Latency Test and a divided attention performance test. The fragmentation of sleep produced significant disruption of nocturnal sleep and reduced daytime alertness. Adaptation in EEG-defined arousals occurred from the 1st to the 2nd night of fragmentation. Threshold (measured indirectly) characteristics of EEG-defined arousals were somewhat different than those of previous studies requiring behavioral awakening. The percent of tone series producing arousal, number of tones necessary for arousal and duration of the arousal all reflected heightened thresholds in stage 3/4 and rapid eye movement (REM) sleep compared to stage 1 and stage 2 sleep. In the last 3 hours of sleep versus the first 3 hours, arousals occurred less frequently, required more tones to produce, resulted in shorter durations and in fewer sleep stage changes, except for REM sleep where the converse was the case.

Acoustic Stimulation↗
PubMed1994

Clinical diagnoses in 216 insomnia patients using the International Classification of Sleep Disorders (ICSD), DSM-IV and ICD-10 categories: a report from the APA/NIMH DSM-IV Field Trial.

Three diagnostic classifications for sleep disorders have been developed recently: the International Classification of Sleep Disorders (ICSD), the Diagnostic and Statistical Manual, 4th edition (DSM-IV), and the International Classification of Diseases, 10th edition (ICD-10). No data have yet been published regarding the frequency of specific diagnoses within these systems or how the diagnostic systems relate to each other. To address these issues, we examined clinical sleep disorder diagnoses (without polysomnography) in 257 patients (216 insomnia patients and 41 medical/psychiatric patients) evaluated at five sleep centers. A sleep specialist interviewed each patient and assigned clinical diagnoses using ICSD, DSM-IV and ICD-10 classifications. "Sleep disorder associated with mood disorder" was the most frequent ICSD primary diagnosis (32.3% of cases), followed by "Psychophysiological insomnia" (12.5% of cases). The most frequent DSM-IV primary diagnoses were "Insomnia related to another mental disorder" (44% of cases) and "Primary insomnia" (20.2% of cases), and the most frequent ICD-10 diagnoses were "Insomnia due to emotional causes" (61.9% of cases) and "Insomnia of organic origin" (8.9% of cases). When primary and secondary diagnoses were considered, insomnia related to psychiatric disorders was diagnosed in over 75% of patients. The more narrowly defined ICSD diagnoses nested logically within the broader DSM-IV and ICD-10 categories. We found substantial site-related differences in diagnostic patterns. These results confirm the importance of psychiatric and behavioral factors in clinicians' assessments of insomnia patients across all three diagnostic systems. ICSD and DSM-IV sleep disorder diagnoses have similar patterns of use by experienced clinicians.

Adolescent↗
PubMed1994

Residual sedating effects of ethanol.

To test for dose and duration effects of residual sedation, ethanol (0.0, 0.5, and 0.9 g/kg) was administered (at 0830, 1030, and 0730 hr, respectively) to 10 healthy, normal-sleeping men, aged 21-35 years. The Multiple Sleep Latency Test was conducted at 0930, 1130, 1330, 1530, 1730, 1930, and 2130 hr, and a divided attention performance assessment was done at 1400, 1600, 1800, and 2000 hr. Breath ethanol concentration for both doses was 0.04% at 1130 hr, 0.01% at 1330 hr, and 0 at 1530 hr. A significant reduction in sleep latency was observed from 0930 to 1530 hr, but not thereafter. Divided attention performance overall was significantly impaired on the 1400-hr test only. These data again showed residual sedation and suggest residual sedation is time limited and not affected in duration or intensity by dose.

Adult↗
PubMed1994

Sleepiness and ethanol effects on simulated driving.

Twelve healthy young men were assessed in each of four experimental conditions presented in a Latin Square design: 8-hr time in bed (TIB) and placebo, 4-hr TIB and placebo, 8-hr TIB and ethanol, and 4-hr TIB and ethanol. After consuming ethanol (0.6 g/kg) or placebo (0900-0930 hr) with 20% supplements at 1030 and 1100 hr, subjects were tested for sleepiness (Multiple Sleep Latency Test at 1000, 1200, 1400, and 1600 hr) and divided attention (1030 hr) performance on day 1, and for simulated driving and divided attention (1000-1200 and 1400-1600 hr) performance on day 2. In the morning testing, with breath ethanol concentrations (BECs) averaging 0.049%, sleepiness was increased, divided attention reaction times increased (on both days), and simulated driving performance was disturbed in the ethanol and 4-hr TIB relative to placebo. Similarly in the afternoon, with BECs averaging 0.013%, the ethanol and 4-hr TIB condition increased sleepiness and disrupted divided attention and simulated driving performance. The results show that sleepiness and low-dose ethanol combine to impair simulated automobile driving, an impairment that extends beyond the point at which BEC reaches zero. They provide a possible explanation for the incidence of alcohol-related automobile accidents at low BECs.

Adult↗
PubMed1994

Diagnostic concordance for DSM-IV sleep disorders: a report from the APA/NIMH DSM-IV field trial.

OBJECTIVE: The frequency and ranking of DSM-IV sleep disorder diagnoses of clinical patients with complaints of insomnia, as well as rates of diagnostic agreement and disagreement between two types of interviewers, were investigated. METHOD: Interviewers at five clinical sites assessed 216 patients referred for insomnia complaints. One sleep specialist and one general clinician interviewed each patient in an unstructured clinical interview, assigned DSM-IV diagnoses, and indicated their reactions to the diagnostic system. RESULTS: Insomnia due to another mental disorder was the most frequent DSM-IV diagnosis across sites, followed by primary insomnia. Interviewers at the five sites differed significantly in the rankings they assigned to different diagnoses. In addition, sleep specialists at most sites diagnosed psychiatric forms of insomnia more frequently than nonspecialists. Kappa values for agreement between the two types of clinicians on multiple DSM-IV sleep diagnoses ranged from 0.26 to 0.80 across sites, indicating moderate agreement overall. Kappa values for individual diagnoses varied across sites and specific diagnoses and ranged from poor to excellent. Interviewers' ratings of their confidence in diagnoses and the fit and ease of use of the DSM-IV categories also showed significant variability related to site and type of interviewer. CONCLUSIONS: The distribution of diagnoses highlights the importance of psychiatric and behavioral factors in the assessment of insomnia. Site-related variability indicates a need for greater standardization in the application of sleep disorder diagnostic criteria. Diagnostic concordance for these diagnoses, while only moderately good, likely reflects actual clinical practice and would be improved through the use of standardized (or structured) interviews and increased training.

Adult↗
PubMed1994

A multicenter, placebo-controlled study evaluating zolpidem in the treatment of chronic insomnia.

BACKGROUND: Zolpidem is a short-acting, nonbenzodiazepine hypnotic with rapid onset of action. Even though it is not a benzodiazepine, it binds to one of three types of central benzodiazepine receptors, showing selective binding to the type 1 benzodiazepine receptor subtype. Therapeutic hypnotic dosages do not disturb normal sleep patterns (sleep architecture). METHOD: A randomized, double-blind, placebo-controlled, parallel group multicenter trial was conducted to determine the effectiveness of 10 mg and 15 mg of zolpidem in the long-term (35 nights) treatment of chronic insomnia in 75 patients. Sleep stage effects and motor and cognitive effects during the 35-night treatment period and the 3-night posttreatment period were also investigated. RESULTS: Within the first week of treatment, 10 mg of zolpidem had a significant effect on latency to persistent sleep and sleep efficiency. Efficacy was maintained throughout the 35 nights of drug administration. There was no evidence of residual effect with 10 mg of zolpidem. Stage 3-4 sleep was preserved at both the 10-mg and 15-mg zolpidem dosages. There was no evidence of tolerance at either dose and no significant treatment differences between the 10-mg zolpidem group and placebo in latency to persistent sleep or sleep efficiency during the posttreatment period. Also, the 10-mg zolpidem dosage was judged by the patients to have helped them fall asleep. Similar results were observed with the 15-mg zolpidem dosage. However, there were significant decreases in REM sleep at Weeks 3 and 4 with 15 mg of zolpidem compared with placebo. Overall, incidence rates of treatment-emergent adverse events in the zolpidem groups were similar to those in the placebo group. CONCLUSION: This is the first sleep laboratory study using a parallel placebo group to demonstrate efficacy for longer than 4 weeks with a hypnotic agent. In this study 10 mg of zolpidem was found to be safe and effective for the long-term treatment of chronic insomnia, demonstrating hypnotic efficacy without affecting sleep stages or producing tolerance effects, rebound effects, or detrimental effects on psychomotor performance. The 15-mg zolpidem dosage provided no clinical advantage over the 10-mg zolpidem dosage.

Adult↗
PubMed1993

The Sleep-Wake Activity Inventory: a self-report measure of daytime sleepiness.

The purpose of this study was to develop a valid multidimensional self-report measure of sleepiness. There were 554 subjects who completed the inventory. The structure of the Sleep-Wake Activity Inventory (SWAI) was derived from principal components analysis. The independent predictive strength of the factors was assessed by forward stepwise regression analysis with the average sleep latency on the Multiple Sleep Latency Test (MSLT) as the dependent variable. The scores on each of the factors were also compared by the level of sleepiness determined by the MSLT (pathological, diagnostic gray area, and normal). Factor analysis showed the existence of six factors on the SWAI (Excessive Daytime Sleepiness [EDS], Psychic Distress, Social Desirability, Energy Level, Ability to Relax and Nocturnal Sleep). The EDS factor was the best predictor of average MSLT. It was also able to differentiate pathological levels of sleepiness from both the diagnostic gray and normal levels of sleepiness. EDS factor scores were sensitive to changes in sleep physiology as improved scores followed normalization of sleep-disordered breathing. The SWAI was shown to be easy to complete, have a multi-dimensional structure, have a EDS factor useful in the prediction of average MSLT scores, be sensitive to differential levels of sleepiness, and change as a result of effective treatment.

Adolescent↗
PubMed1993

Integrin overexpression induced by high glucose and by human diabetes: potential pathway to cell dysfunction in diabetic microangiopathy.

The nature of the process leading to the acellular nonperfused capillaries of diabetic microangiopathy remains unknown. Because these capillaries manifest thickened basement membranes, we asked whether the process causing deposition of excess extracellular matrix in diabetes modifies cell-matrix interactions in a direction that would compromise cell renewal. In 44 individual isolates of human umbilical vein endothelial cells we observed that high glucose concentrations (30 mM) induce coordinate increases in the levels of mRNAs encoding fibronectin and the fibronectin-specific integrin receptor alpha 5 beta 1 as well as in the cognate proteins. Expression of the integrin subunit alpha 3, component of the alpha 3 beta 1 polyspecific receptor for fibronectin, laminin, and collagen, was also up-regulated by high glucose. Overexpression of integrins correlated with increased cell attachment to exogenous fibronectin and laminin as well as to complex matrix. Moreover, cells exhibited firmer steady-state adhesion to their own matrix. To correlate these in vitro observations with events in human diabetic retinopathy we measured integrin levels in retinal trypsin digests prepared from 10 patients with 8.2 +/- 1.6 (mean +/- SE) years of diabetes and 10 age- and sex-matched nondiabetic controls. Microvessels of diabetic patients showed increased immunostaining for beta 1 integrin (P = 0.025) when compared with control microvessels. These data show that high glucose and diabetes increase integrin expression and thus alter the interaction of vascular endothelial cells with their basement membranes in the direction of firmer cell-matrix adhesion. This could compromise the migration and replication critical to the reendothelialization process and contribute to microvascular occlusion.

Cell Adhesion↗
PubMed1993

Variations in acoustical beam properties of intracoronary Doppler catheters.

The limitations of coronary angiography in assessing the functional significance of coronary obstructions is well known. While the critical variable of coronary blood flow cannot be readily measured, intraluminal Doppler sonography offers useful related functional information on blood flow velocity. In order to fully evaluate Doppler signals it is essential to have exact knowledge of the transducer transmission characteristics and of the ultrasound beam topology. In an experimental set-up, the transmitter-receiver characteristics of five commonly used Doppler catheters were investigated. In comparing the beam characteristics we found inhomogeneities in the lateral beam spread. At a penetration depth of 3.0 mm the beam shape varied from a minimum of 1.25 mm up to a maximum of 3.5 mm. The mean was 2.25 mm. The different beam profiles of the investigated Doppler transducers cause an error in measuring the blood flow velocity. The blood flow velocity tends to be underestimated the more the vessel diameter and the blood flow velocity increase. Contrary to transducer design optimized for imaging, for spectral analysis of the Doppler signal it would be advantageous to have as broad a beam as possible in order to illuminate the entire vessel lumen.

Angioplasty, Balloon, Coronary↗
PubMed1993

Effects of ethanol, diphenhydramine, and triazolam after a nap.

This study assessed the capacity of a 60-minute nap to reverse the sedating and performance-disruptive effects of ethanol, triazolam, and Diphenhydramine. Twelve healthy, young men received (at 0800 to 0830) .6 g/kg ethanol and a placebo pill, .25 mg triazolam and ethanol placebo, 50 mg Diphenhydramine and ethanol placebo, and a placebo pill and ethanol placebo on each of 2 days in a Latin Square design. On one treatment day (at 0900 hour) subjects were allowed a 60-minute nap and on the other a sleep latency test (no nap). Then, sleep latency was tested (by Multiple Sleep Latency Test [MSLT] at 1100, 1300, 1500, and 1700) and divided attention performance assessed (at 1130). The nap reversed the sedative effects of ethanol and Diphenhydramine and reduced those of triazolam (on MSLT). The nap reduced the performance-disruptive effects of ethanol and Diphenhydramine but not those of triazolam. Given the differing neurobiological mechanisms of these drugs, the data suggest that some of their effects are nonspecific and result from activation of sleep mechanisms that a nap can reverse.

Adult↗
PubMed1993

[Functional and cancerologic aspects in the use of jejunum in the ENT area].

In this article, we report about the experiences at our ENT-University Clinic in Vienna in 76 patients with free transplanted microvascularly anastomosed autologous jejunum used for reconstruction following extensive resection of mainly stage IV carcinomas in the head and neck. Jejunum was inserted as a siphon-like tube between the trachea and the hypopharynx in 43 patients primarily for restoration of speech (in 10 cases the pharynx was also reconstructed). In 33 patients, the upper digestive tract was reconstructed, as either patch or tube. They were then evaluated according to functional results of speech and swallowing, aesthetics as well as 5-year survival rates. We achieved good results in 35 speech patients (81.4%) and in 22 swallowing patients (66.6%). The aesthetic function was influenced favourably because the volume of the jejunal transplant fills up the defect in the neck after resection and creates a tolerable neck-shape. The 5-year survival of all available 54 patients was 26%, patients for speech restoration 31.7% and patients for swallowing restoration 17.5%. These results are to be considered under the aspect that patients with swallowing restoration primarily had more severe disease. Complications such as like perioperative mortality and total necrosis can be avoided by careful evaluation of the patients to be operated on. With the experiences gained from this study, we now have exact indications for the use of jejunum grafts and thus can expect very high rates of success.

Adenocarcinoma↗
PubMed1993

Level of sleepiness and total sleep time following various time in bed conditions.

The effects of various time in bed (TIB) conditions on daytime sleepiness and total sleep time (during a 24-hour enforced bedtime) were investigated. Thirty-two healthy male subjects participated in the study. Subjects were assigned to one of four groups to balance average screening multiple sleep latency tests (MSLT). Subjects were randomly assigned to spend 8, 6, 4 or 0 hours time in bed. They underwent the same TIB condition twice with at least 7 days between the two sessions. Following their assigned time in bed conditions, subjects were counterbalanced to have a standard MSLT and a 24-hour enforced bedtime protocol. To assess the effect of TIB on the MSLT, the sleep latencies were submitted to a four (TIB condition) by four (nap test) multivariate analysis of variance. The sleep latencies were shorter for those subjects in the 0-hours condition when compared to the other three conditions. Also, the sleep latencies of those subjects in the 4- and 6-hour conditions were comparable but different from those of subjects in the 8- and 0-hour TIB conditions. To assess the effect of TIB on the 24-hour enforced bedtime, the total sleep time during this period was submitted to a six (4-hour block) by four (TIB condition) multivariate analysis of variance. Subjects slept more following 0 hours TIB when compared to the other three conditions. There were no statistically significant differences between the 8-, 6- and 4-hour TIB conditions. Across conditions, subjects slept more during the first 4 hours when compared to blocks 2, 3, 4 and 5. Blocks 1 and 6 were comparable.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Sedative effects and plasma concentrations following single doses of triazolam, diphenhydramine, ethanol and placebo.

Twelve, healthy, young men received 0.25 mg triazolam and ethanol placebo, 50 mg diphenhydramine and ethanol placebo, 0.6 g/kg ethanol and placebo pill and ethanol placebo and placebo pill in a double-blind Latin Square design. Each of the four treatments were administered for 2 days at 0900 hours with blood samples drawn on day one at 0830, 1030, 1230, 1430 and 1630 hours, and sleep latency and performance assessed on day two at 1000, 1200, 1400 and 1600 hours. Significant sedative effects of ethanol, triazolam and diphenhydramine relative to placebo were observed on the sleep latency and performance measures with the effects being detected over the full 6.5 hours of assessment. Among the active drugs, triazolam and diphenhydramine had similar sedative effects which differed from that of ethanol. Plasma concentration of each drug declined significantly over the 6.5 hours. Ethanol reached zero, but triazolam and diphenhydramine did not. Continued sedation (sedative effects after plasma concentration reached zero) was observed with ethanol.

Adult↗