Biomedical subjects

G Gruber

Publications and source records attributed to G Gruber.

At least 37 records · Page 2Linked to original sources

PubMed2002

[Possibilities and limitations of ultrasonography in corticotomy/callus distraction].

Sonographic examination can yield additional information free of radiation in the course of corticotomy/callus distraction. The echogenic structures of the cortical structure and the callus between can be scanned at the area of the callus distraction by ultrasound examination. Individual sectional planes are focussed. They are different from the standardized ultrasound examination. Depending on when the corticotomy was performed, the callus between the cortical structures can be visualized sonographically. First it is echo poor, and then it becomes more and more echogenic. The ultrasound examination can give additional information during the first 4 weeks after corticotomy/callus distraction. A deviation of the axis in the area of callus distraction cannot be judged reliably. A sonographically guided division into three stages is possible.

Bony Callus↗

PubMed2002

[Ultrasound determination of leg length].

A diagnostic method is presented for measuring the leg length and the difference in leg lengths with ultrasound. A special device for holding and moving the ultrasound transducer was constructed. The measuring points on the hip, knee, and upper ankle can be visualized with a 5- or 7.5-MHz linear scanner. The measuring device gives the distance of the points in centimeters so that the difference corresponds to the real length of the leg, femur, and tibia. Tests conducted on corpses and clinical examples show that ultrasound in combination with our special device is an ideal method for determining the exact length of the leg. Ultrasound measurement of the leg length offers a reliable, noninvasive, and easily performed method. Because ultrasound is not limited by radiation hazards, our technique can be used for clinical screening.

Adolescent↗

PubMed2002

[Physical training as interval or continuous training in chronic heart failure for improving functional capacity, hemodynamics and quality of life--a controlled study].

We conducted a three-week randomized trial comparing the improvement of functional capacity by exercise training in chronic heart failure by the steady-state (EF 27.3%, n = 20) and the interval modus (EF 29.3%, n = 20) with a control group (EF = 26.6%, n = 10). Minimal EF was 10%, the lowest maximal oxygen consumption was 9.3 ml/kg/min and the lowest cardiac output was 1.9 l/min; 9 patients had been evaluated for HTX. VO2 at the anaerobic threshold and at maximal exercise increased in the continuous exercise group by 1.4 or 1.6 ml/kg/min, respectively, corresponding to an increase of 13.7% (p < 0.05) and 9.3% (p < 0.05). In the interval training group the increase was 1.3 and 1.5 ml/kg/min corresponding to 14% (p < 0.05) and 8.1% (p < 0.05). Continuous short-term exercise had no impact to central hemodynamics as pulmonary artery pressure (PA), capillary wedge pressure (pc), cardiac index (CI) or stroke volume index (SVI), whereas after interval training a significant increase at maximal exercise could be seen in CI (p < 0.05) and SVI (p < 0.01) with a concomitant drop in systemic peripheral resistance (p < 0.05) compared to the steady-state modus. Interval training was further characterized by a higher short-term but lower mean work load with a significantly smaller increase in lactate. Quality of life was improved according to the SF-36 questionnaire in both training groups but the psychologic sum factor was three times as high, increasing to 24.2% in the steady-state exercise group. It can be concluded that clinically stable patients with heart failure and even those already having been evaluated for cardiac transplantation profit from short-term physical training. Both training modalities seem equally suited to improve functional capacity. However interval training leads to more pronounced improvement in hemodynamics compared to the steady-state exercise, whereas the later had a greater impact on psychological well-being and quality of life. Patients with heart failure and severe peripheral deconditioning tolerate higher workloads with more peripheral stress by an interval training modus. Long-term training modalities need to be established to further improve and stabilize functional status.

Activities of Daily Living↗

PubMed2002

Monitoring pollution by proton-transfer-reaction mass spectrometry during paediatric anaesthesia with positive pressure ventilation via the laryngeal mask airway or uncuffed tracheal tube.

Twenty children aged 2-66 months were randomly allocated for airway management with either the laryngeal mask airway or uncuffed tracheal tube using intermittent positive pressure ventilation with a tidal volume of 8 ml.kg-1 and a respiratory rate adjusted to maintain end-expiratory carbon dioxide concentration at 5.3 kPa. Induction was with fentanyl/propofol and maintenance was with sevoflurane 2.5% in oxygen/air. The airway device was removed when the patients were awake and the patients were transferred to the postanaesthesia care unit 10 min later. Air was sampled from a point 1.5 m above the floor at a location remote from the ventilation outlet and analysed using a proton-transfer-reaction mass spectrometer capable of continuous trace gas analysis at the parts per billion volume (ppbv) level. The concentration of sevoflurane was recorded every minute during three consecutive phases: for 5 min before the introduction of sevoflurane (background); after introduction of sevoflurane until removal of the airway device (intra-operative); and every minute after removal until the concentration returned to background levels. Median (interquartile range [range]) intra-operative sevoflurane concentrations were 200-400 times higher than background values for the laryngeal mask airway 1 (1-2 [0-3]) ppbv vs. 404 (278-523 [83-983]) ppbv, respectively, and the tracheal tube 2 (1-3 [0-5]) ppbv vs. 396 (204-589 [107-1735]) ppbv (both p < 0.0001), and returned to background values within 5 min of removal. There were no differences in sevoflurane concentration between devices intra-operatively or after removal. The performance of the proton-transfer-reaction mass spectrometer was identical at the start and end of the 30-day study. We conclude that peri-operative sevoflurane concentration in a modern operating theatre is similar for the laryngeal mask airway and the uncuffed tracheal tube in paediatric patients receiving intermittent positive pressure ventilation. Intra-operative sevoflurane concentrations are five times lower than occupational safety limit requirements, and 1000 times lower 5 min after removal of the airway device with the patient awake. The proton-transfer-reaction mass spectrometer has potential for monitoring air quality in the operating theatre.

Air Pollutants, Occupational↗

PubMed2002

Neopterin as a marker of immunostimulation: an investigation in anaesthetic workplaces.

Personnel working in operating theatres and recovery rooms are exposed to a variety of noxious substances. The results of studies of the effects of occupational exposure on immune parameters are conflicting. Neopterin is an acknowledged marker of immunostimulation. Urinary neopterin levels of 58 anaesthetists and anaesthetic nurses were measured over a 3-week period. Neopterin analyses were performed using high performance liquid chromatography. Neopterin levels were within the normal range for all subjects. Younger subjects (aged < or = 35 years) had significantly higher urinary neopterin concentrations than older subjects (aged > 35 years). The present study is the first to investigate the influence of anaesthetic exposure on neopterin levels. No evidence of immunostimulation was found.

Adult↗

PubMed2001

Constitutive activation of hypoxia-inducible genes related to overexpression of hypoxia-inducible factor-1alpha in clear cell renal carcinomas.

The transcription factor hypoxia-inducible factor (HIF)-1 is an important mediator of hypoxic adaptation of tumor cells and controls several genes that have been implicated in tumor growth. Oxygen-dependent degradation of HIF-1alpha, the regulatory subunit, requires binding to the von Hippel Lindau (VHL) protein. Because functional inactivation of the VHL tumor suppressor gene occurs in up to 70% of clear cell renal carcinomas, we investigated whether this results in overexpression of HIF-1alpha and its target genes. Immunoblotting revealed increased expression of HIF-1alpha in 24 of 32 (75%) clear cell renal carcinomas but only 3 of 8 non-clear cell renal tumors. Somatic mutations of the VHL gene were detected only in clear cell renal carcinomas that overexpressed HIF-1alpha. None of the HIF-1alpha-negative tumors displayed a VHL mutation. The level of HIF-1alpha mRNA was not different between tumors and adjacent kidney tissue. Immunohistochemistry revealed distinct patterns of nuclear staining for HIF-1alpha, depending on histological type and overall abundance of HIF-1alpha. In those clear cell renal carcinomas that showed increased expression on immunoblots, HIF-1alpha was expressed in almost all cells. In the remaining clear cell and in non-clear cell tumors, staining was focal; these different patterns thus were compatible with genetic stabilization in contrast to microenvironmental stimulation of HIF-1alpha as the primary mechanism. The mRNA expression of two known target genes of HIF-1alpha, vascular endothelial growth factor and glucose transporter 1, increased progressively with increasing amounts of HIF-1alpha in tumor extracts. In addition, glucose transporter 1 protein levels correlated with HIF-1alpha abundance. In conclusion, the data provide in vivo evidence for a constitutive up-regulation of HIF-1alpha in the majority of clear cell renal carcinomas, which leads to more widespread accumulation of this transcription factor than hypoxic stimulation. These observations are most likely linked to functional inactivation of the VHL gene product. Increased expression of HIF-1alpha is associated with alterations in gene expression patterns that are likely to contribute to tumor phenotype and progression.

Adenocarcinoma, Clear Cell↗

PubMed2001

Activity monitoring in sleep research, medicine and psychopharmacology.

Motor activity as a diagnostic parameter has become an important feature in many fields of medicine and psychology. The concept of mobility and immobility implies the assumption that mental and behaviour disorders involve abnormal activity that can be measured to characterise the disorder itself, to diagnose its presence and to document the impact of treatment. In sleep research, activity monitoring by wrist actigraphs has proven its usefulness as an efficient method to assess the rest-activity cycle over long time periods and to estimate sleep-related features such as sleep efficiency and total sleep time. But like many other techniques and devices, activity monitoring has some limitations and drawbacks. This paper describes the basic features of wrist actigraphy in measuring nocturnal and daytime motor activity.

Chronobiology Phenomena↗

PubMed2001

Analysis of volatile organic compounds: possible applications in metabolic disorders and cancer screening.

The human breath contains a variety of endogenous volatile organic compounds (VOCs). The origin and pathophysiological importance of these VOCs is poorly investigated. Little is known about the interaction of VOCs from ambient air, such as those produced by plants and exhaust fumes, with the human organism. Gas chromatographic determination of VOC concentrations is tedious. Proton-transfer-mass spectroscopy (PTR-MS), a new technology for the online detection of VOC patterns, is a valuable alternative. We present two interesting molecular species, isoprene and ortho (o)-toluidine, as examples of endogenously produced VOCs. In a case study, breath isoprene reductions during lipid-lowering therapy (36%) were shown to correlate with cholesterol (32%) and LDL concentrations (35%) in blood (p < 0.001) over a period of 15 days. Therefore, isoprene concentrations in human breath (measured by PTR-MS) might serve as an additional parameter to complement invasive tests for controlling lipid-lowering therapy. Furthermore, it may be a useful parameter for lipid disorder screening. Mass-108, which presumably represents o-toluidine in our breath samples, was found in significantly higher concentrations in the breath of patients with different tumors (1.5 +/- 0.8 ppbv) than in age-matched controls (0.24 +/- 0.1 ppbv, p < 0.001). Inflammatory reactions do not seem to alter the pattern of mass-108. Therefore, it appears to be a currently underestimated carcinoma marker that deserves further investigation.

Adult↗

PubMed2001

Low-resolution brain electromagnetic tomography revealed simultaneously active frontal and parietal sleep spindle sources in the human cortex.

Analyses of scalp-recorded sleep spindles have demonstrated topographically distinct slow and fast spindle waves. In the present paper, the electrical activity in the brain corresponding to different types of sleep spindles was estimated by means of low-resolution electromagnetic tomography. In its new implementation, this method is based on realistic head geometry and solution space is restricted to the cortical gray matter and hippocampus. In multichannel all-night electroencephalographic recordings, 10-20 artifact-free 1.25-s epochs with frontally, parietally and approximately equally distributed spindles were marked visually in 10 normal healthy subjects aged 20-35years. As a control condition, artifact-free non-spindle epochs 1-3s before or after the corresponding spindle episodes were marked. Low-resolution electromagnetic tomography demonstrated, independent of the scalp distribution, a distributed spindle source in the prefrontal cortex (Brodmann areas 9 and 10), oscillating with a frequency below 13Hz, and in the precuneus (Brodmann area 7), oscillating with a frequency above 13Hz. In extremely rare cases only the prefrontal or the parietal source was active. Brodmann areas 9 and 10 have principal connections to the dorsomedial thalamic nucleus; Brodmann area 7 is connected to the lateroposterior, laterodorsal and rostral intralaminar centrolateral thalamic nuclei. Thus, the localized cortical brain regions are directly connected with adjacent parts of the dorsal thalamus, where sleep spindles are generated. The results demonstrated simultaneously active cortical spindle sources which differed in frequency by approximately 2Hz and were located in brain regions known to be critically involved in the processing of sensory input, which is in line with the assumed functional role of sleep spindles.

Adult↗

PubMed2001

Restless legs syndrome (RLS) and periodic limb movement disorder (PLMD): acute placebo-controlled sleep laboratory studies with clonazepam.

Restless legs syndrome (RLS) - a common sensorimotor disorder - and periodic limb movement disorder (PLMD) are currently treated with substances of four classes: dopaminergic agents, which are considered the drugs of choice, benzodiazepines, opioids and anticonvulsants. As their effects on sleep variables differ considerably, the aim of the present placebo-controlled sleep laboratory study was to measure the acute effects of 1 mg clonazepam on objective and subjective sleep and awakening quality in ten RLS and 16 PLMD patients, utilizing polysomnography (PSG) and psychometry. Descriptive data analysis demonstrated at the confirmatory level concerning three target variables that - as compared with placebo - clonazepam significantly improved objective sleep efficiency and subjective sleep quality in both patient groups, but failed to reduce the index PLM/h of sleep. At the descriptive level, in PLMD clonazepam improved PLM during time in bed, REM and wakefulness and showed more significant changes in various sleep and awakening measures than in RLS patients, though there were no significant inter-group differences. In conclusion, in both PLMD and RLS clonazepam exhibited acute therapeutic efficacy regarding insomnia, which is quite different from the mode of action of dopamine agonists.

Adult↗

PubMed2001

[Percutaneous radiotherapy--indications for and differentiation from surgical treatment of metastases].

One third up to half of the patients treated by the radiation oncologist are referred for palliative radiation therapy because of distant metastases, mostly for painful bone or symptomatic brain metastases. As malignant cells are often disseminating long before diagnosis and therapy of the primary tumor, solitary metastases occur very seldom. A single and good resectable brain metastasis is a well-known indication for surgical intervention, especially at infratentorial location. In spherical metastases below a size of 3 cm stereotaxic radio-surgery can be alternatively considered, especially at paramedian location. Bone metastases need more often a surgical therapy, e.g. an impending or already happened fracture of long hollow bones, or radio-resistent tumors of hands and feet. Surgical therapy of metastatic vertebrae are often demanding enormous efforts and skills. Indications for surgery are osteolytical metastases with potential static problems, highly advanced destruction and most of all symptoms of spinal cord compression. The radiation oncologist is well advised to make sure of the surgeon's partnership in regard to the treatment of metastases.

Bone Neoplasms↗

PubMed2000

[Daytime tiredness correlated with nocturnal respiratory and arousal variables in patients with sleep apnea: polysomnographic and EEG mapping studies].

There is evidence that daytime tiredness is caused by apnea/hypopnea with oxygen desaturation and/or by sleep fragmentation due to arousals. The aim of this study was to investigate objective and subjective sleep and awakening quality and daytime vigilance--objectified by midmorning mapping of vigilance-controlled EEG (V-EEG)--in sleep apnea patients (N: 18), as compared with age- and sex-matched normal controls (N: 18) as well as to correlate nocturnal respiratory distress and arousals to daytime brain function. Statistical analyses demonstrated a deterioration in subjective and objective sleep and awakening quality in apnea patients. Midmorning V-EEG mapping in apnea patients exhibited less total power, more delta and theta, less alpha and beta activity, as well as a slower dominant frequency and centroid of the total activity compared to controls, which suggests a vigilance decrement. The Spearman rank correlation between 6 polysomnographically registered respiratory variables and 36 diurnal quantitative EEG measures demonstrated the following: the higher the apnea, apnea-hypopnea, snoring and desaturation indices and the lower the minimum and average low oxygen saturation, the more pronounced was diurnal tiredness. Eleven arousal measures based on ASDA criteria showed the following significant correlations: the higher the nocturnal arousal index and the more arousals due to hypopneas, the greater was daytime tiredness. On the other hand, the greater the average frequency change during arousals and the more spontaneous arousals, the better was daytime vigilance. Our findings show that, in contrast to the lengthy Multiple Sleep Latency (MSLT) and Maintenance of Wakefulness (MWT) tests which evaluate sleep pressure under resting conditions conducive to sleep, V-EEG mapping provides a brief objective measure of a sleep apnea patient's daytime tiredness under conditions of wakefulness more appropriate to reflect the patient's everyday life.

Adult↗

PubMed2000

Structural and functional features of the Escherichia coli F1-ATPase.

The structural organization and overall dimensions of the Escherichia coli F1-ATPase in solution has been analyzed by synchroton X-ray scattering. Using an independent ab initio approach, the low-resolution shape of the hydrated enzyme was determined at 3.2 nm resolution. The shape permitted unequivocal identification of the volume occupied by the alpha3beta3gamma complex of the atomic model of the ECF1-ATPase. The position of the delta and epsilon subunits were found by interactive fitting of the solution scattering data and by cross-linking studies. Laser-induced covalent incorporation of 2-azido-ATP established a direct relationship between nucleotide binding affinity and the different interactions between the stalk subunits gamma and epsilon with the three catalytic subunits (beta) of the F1-ATPase. Mutants of the ECF1-ATPase with the introduction of Trp-for-Tyr replacement in the catalytic site of the complex made it possible to monitor the activated state for ATP synthesis (ATP conformation) in which the gamma and epsilon subunits are in close proximity to the alpha subunits and the ADP conformation, with the stalk subunits are linked to the beta subunit.

Escherichia coli↗

PubMed2000

[Standardized sonographic examination of the hip joint].

AIM: We demonstrate a technique for examining the hip joint sonographically in a standardised way using sectional planes corresponding to the guidelines provided by the work group "Sonography of the Musculo-Skeletal System" of the German Society of Ultrasound (DEGUM). MRT-scans were used as a comparative standard. METHOD: The ultrasound examination was performed in the following standardised way: a transversal and longitudinal scan were done in the ventral region and additionally a longitudinal scan in the lateral region. In cases without pathological findings two standardised planes should be documented. In the case of pathological findings the picture should be documented in two standardised planes and compared to the corresponding contralateral site. An ultrasound examination standardised in this way facilitates a precise assessment of the ventral joint capsule, the bone structures, the ventral and lateral aspects of the glenoid cavity and the peri-articular soft tissue structures of the hip joint. RESULTS: An examination technique is presented which offers additional pictorial information, saves costs and is not harmful to the patient. CONCLUSION: The ultrasound examination of the hip joint can supply additional information about diseases and traumatic changes in this region. In paediatric hip disorders such as transient synovitis, septic arthritis, juvenile arthritis, Leg-Calvé-Perthes disease and slipped femoral epiphysis, the ultrasound examination can provide important additional information for the initial differential diagnosis and during follow-up.

Germany↗

PubMed2000

Do we need MR images for diagnosing tendon ruptures of the distal biceps brachii? The value of ultrasonographic imaging.

AIM: To assess the usefulness of ultrasound in the diagnosis of rupture of the distal biceps brachii muscle by demonstrating the clear differentiation between the distal biceps muscle and the surrounding soft tissue in a standardized section of the elbow. METHOD: Under sonographic guidance five biceps muscles of three cadavers were marked with a needle in the region of the elbow joint. Thereafter an anatomical preparation of the distal biceps brachii muscle followed to verify the correct positioning of the needle. Real time ultrasound was performed with a 7.5 MHz linear array transducer. The standard section of the elbow and the images on the screen correspond to the guidelines provided by the German Society of Ultrasonography in the Locomotor Apparatus (DEGUM). RESULTS: In all five cases the needle tip could be found in the middle of the distal biceps muscle. It was possible to perform a sonographically guided puncture of the muscle and to differentiate between distal biceps brachii and surrounding soft tissues using a high resolution transducer of the newest generation in ultrasound technology. CONCLUSION: Our investigation confirmed our clinical ultrasound findings in distal biceps tendon ruptures. The echo-intense signal is replaced by a hypoechogenic signal representing the haematoma in the area of the distal biceps brachii muscle. In addition to the clinical examination in case of a ruptured distal biceps muscle ultrasound of the elbow is a valuable and reliable imaging method to support the diagnosis. MRI of the elbow is not always necessary to confirm the diagnosis.

Female↗

PubMed2000

Audit and recurrence rates after hernia surgery.

OBJECTIVE: To study the effect of quality assurance on the recurrence rate after hernia repair. DESIGN: A prospective longitudinal cohort study. SETTING: District hospital, Sweden. SUBJECTS: All (n = 1232) patients aged 15-80 years operated upon for inguinal or femoral hernia in Motala 1984, 1986-1988, 1990, and 1992-1994. INTERVENTION: A questionnaire enquiring about pain or a lump in the operated area was sent 3-6 years postoperatively to all patients, excluding those who had already been operated on for recurrence and those who had died. Selected cases were examined depending on the answers to the questionnaire. MAIN OUTCOME MEASURES: Recurrence rate estimated by adding already confirmed recurrences to those found at the clinical examination; reoperation for recurrence; hospital stay; and number of day cases. Cumulative incidence of reoperation was analysed by actuarial analysis of all patients operated on from 1986-1997. RESULTS: The recurrence rate decreased from 18% in 1984 and 1986 to 3% in 1993 and 1994. The reoperation rate for recurrence at three years was 10.8% (95% confidence interval, CI: 9.3 to 12.2%), 3.6% (2.6 to 4.4%) and 2.2% (1.7 to 2.7%) for patients operated on between 1986-1988, 1989-1991 and 1992-1997, respectively. Differences between the first and the second and between the first and the third period were both highly significant (p < 0.001) whereas the difference between the second and third period was not (p = 0.09). Mean hospital stay decreased from 3.5 days in 1984 to 0.9 days in 1994. CONCLUSION: By recording recurrence rate or its surrogate endpoint, reoperation rate for recurrence, or both, hospital stay, and number of day cases, and presenting these results to participating surgeons, we provided incentives to improve outcome. This has resulted in a rapid decrease in recurrence rate and a shortened hospital stay, thereby improving cost-effectiveness.

Adolescent↗

PubMed2000

Placebo-controlled sleep laboratory studies on the acute effects of zolpidem on objective and subjective sleep and awakening quality in nonorganic insomnia related to neurotic and stress-related disorder.

UNLABELLED: Recent investigations in our sleep outpatient clinic demonstrated that 30% of patients exhibited organic and 70% nonorganic sleep disorders, with 41% showing as an additional diagnosis neurotic, stress-related, and somatoform disorders, 31% affective disorders and 15% mental and behavioral disorders due to psychoactive substance use. Thus, the aim of the study was to investigate the acute effects of the imidazopyridine zolpidem on objective and subjective sleep and awakening quality in the largest of the above-mentioned groups. In this single-blind, placebo-controlled cross-over study, 15 patients (9 females and 6 males aged 51.1 + 11. 3 years) diagnosed as having nonorganic insomnia (ICD-10: F 51.0) related to neurotic and stress-related disorders (F 1.1:12, F 41.2:2 and F 43.2:1) were included. Objective and subjective sleep and awakening quality measures were investigated in 3 subsequent nights in the sleep laboratory (adaptation, baseline/placebo and zolpidem 10 mg night), utilizing clinical, polysomnographic, psychometric and psychophysiological methods. The drug-free patients were matched according to age and sex with 15 normal healthy controls (age 51.2 + 11.8 years). Statistical analysis of polysomnographic variables demonstrated a significant lengthening of the total sleep period (TSP) and total sleep time (TST), an improvement in sleep efficiency and a shortening of sleep latencies after zolpidem as compared with placebo. These changes were opposite to the differences between patients and controls. Concerning sleep architecture, zolpidem increased the length of S4 and S3 + S4 as compared with placebo. Subjective sleep and awakening quality and the thymopsychic variables drive, mood, affectivity and wakefulness in the morning showed no significant changes, as a significant improvement had already occurred from the adaptation to the baseline/placebo night. Noopsychic variables (attention, concentration, attention variability, numerical memory, fine motor activity, reaction time measures) showed similar findings. Moreover, subjective sleep and awakening quality, thymopsychic and noopsychic measures during baseline/placebo recordings did not differ significantly from normative data (except for fine motor activity). Psychophysiological measures did not show any significant alterations either, except for a decrease in systolic blood pressure in the evening. CONCLUSION: As compared with placebo, zolpidem induced a significant improvement in objective sleep quality, mainly by increasing TSP, TST and sleep efficiency and shortening sleep latencies, thereby normalizing the disorder of initiating and maintaining sleep. Deep sleep stages S3 + S4 increased (although at baseline/placebo these stages did not differ from controls), while S1, S2 and SREM did not change significantly. Subjective sleep and awakening quality as well as thymopsychic and noopsychic performance in the morning mainly showed a placebo and 'first- night effect' phenomenon in these patients. Thus, the changes induced by zolpidem were somewhat different from those after classical benzodiazepines.

Cross-Over Studies↗

PubMed2000

Sleep laboratory studies in restless legs syndrome patients as compared with normals and acute effects of ropinirole. 1. Findings on objective and subjective sleep and awakening quality.

Although the restless legs syndrome (RLS) is a disorder with a relatively high prevalence rate (8% in Austria) and leads to insomnia and excessive daytime tiredness, there is a paucity of sleep laboratory data concerning objective and subjective sleep and awakening quality. Thus, the aim of this study was to investigate 12 untreated RLS patients as compared with 12 normal controls and subsequently measure the acute effects of 0.5 mg ropinirole (Requip((R))) - a nonergoline dopamine agonist - as compared with placebo. In 3 nights (adaptation, placebo, ropinirole night) sleep induction, maintenance and architecture were measured objectively by polysomnography, subjective sleep and awakening quality were assessed by self-rating scales and visual-analog scales, and objective awakening quality was evaluated by a psychometric test battery. In polysomnography, RLS patients demonstrated, as compared with normal controls, a decreased total sleep time (TST) and sleep efficacy, increased wakefulness during the total sleep period and frequency of nocturnal awakenings, increased sleep stage S1, decreased S2 and increased stage shifts. Subjective sleep quality tended to decrease, and morning well-being, mood, affectivity and wakefulness were deteriorated. In the noopsyche, fine motor activity and reaction time performance were deteriorated. Ropinirole 0.5 mg induced, as compared with placebo, an increase in TST, sleep efficacy, S2 sleep and stage shifts. In the morning, somatic complaints increased slightly, while fine motor activity and reaction time performance improved. Our findings suggest a key-lock principle in the diagnosis/treatment of RLS and a dopaminergic mechanism in its pathogenesis, which is supported by the data on periodic leg movements during sleep and arousals of the subsequent paper.

Administration, Oral↗