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Winfried Meissner

Publications and source records attributed to Winfried Meissner.

12 recordsLinked to original sources
PubMed2006

Comparison of orally administered cannabis extract and delta-9-tetrahydrocannabinol in treating patients with cancer-related anorexia-cachexia syndrome: a multicenter, phase III, randomized, double-blind, placebo-controlled clinical trial from the Cannabis-In-Cachexia-Study-Group.

PURPOSE: To compare the effects of cannabis extract (CE), delta-9-tetrahydrocannabinol (THC), and placebo (PL) on appetite and quality of life (QOL) in patients with cancer-related anorexia-cachexia syndrome (CACS). PATIENTS AND METHODS: Adult patients with advanced cancer, CACS, weight loss (> or = 5% over 6 months), and Eastern Cooperative Oncology Group (ECOG) performance status (PS) < or = 2 were randomly assigned (2:2:1) to receive CE (standardized for 2.5 mg THC and 1 mg cannabidiol) or THC (2.5 mg) or PL orally, twice daily for 6 weeks. Appetite, mood, and nausea were monitored daily with a visual analog scale (VAS); QOL was assessed with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 (composite score: questions 29 and 30). Cannabinoid-related toxicity was assessed every 2 weeks. RESULTS: Of 289 patients screened, 243 were randomly assigned and 164 (CE, 66 of 95 patients; THC, 65 of 100 patients; and PL, 33 of 48 patients) completed treatment. At baseline, groups were comparable for age (mean, 61 years), sex (54% men), weight loss (32% > or = 10%), PS (13% ECOG = 2), antineoplastic treatment (50%), appetite (mean VAS score, 31/100 mm), and QOL (mean score, 30/100). Intent-to-treat analysis showed no significant differences between the three arms for appetite, QOL, or cannabinoid-related toxicity. Increased appetite was reported by 73%, 58%, and 69% of patients receiving CE, THC, or PL, respectively. An independent data review board recommended termination of recruitment because of insufficient differences between study arms. CONCLUSION: CE at the oral dose administered was well tolerated by these patients with CACS. No differences in patients' appetite or QOL were found either between CE, THC, and PL or between CE and THC at the dosages investigated.

Administration, Oral↗
PubMed2006

Analysis of complex physiological systems by information flow: a time scale-specific complexity assessment.

In the last two decades conventional linear methods for biosignal analysis have been substantially extended by non-stationary, non-linear, and complexity approaches. So far, complexity is usually assessed with regard to one single time scale, disregarding complex physiology organised on different time scales. This shortcoming was overcome and medically evaluated by information flow functions developed in our research group in collaboration with several theoretical, experimental, and clinical partners. In the present work, the information flow is introduced and typical information flow characteristics are demonstrated. The prognostic value of autonomic information flow (AIF), which reflects communication in the cardiovascular system, was shown in patients with multiple organ dysfunction syndrome and in patients with heart failure. Gait information flow (GIF), which reflects communication in the motor control system during walking, was introduced to discriminate between controls and elderly patients suffering from low back pain. The applications presented for the theoretically based approach of information flow confirm its value for the identification of complex physiological systems. The medical relevance has to be confirmed by comprehensive clinical studies. These information flow measures substantially extend the established linear and complexity measures in biosignal analysis.

Adult↗
PubMed2005

Gait information flow indicates complex motor dysfunction.

Gait-related back movements require coordination of multiple extremities including the flexible trunk. Ageing and chronic back pain influence these adjustments. These complex coordinations can advantageously be quantified by information theoretically based communication measures such as the gait information flow (GIF). Nine back pain patients (aged 61+/-10 yr) and 12 controls (aged 38+/-10 yr) were investigated during normal walking across a distance of 300 m. The back movements were measured as distances between characteristic points (cervical spine CS, thoracic spine TS, lumbar spine LS) by the sonoSens Monitor, a system for mobile motion analysis. Gait information flow and regularity indices (RI1: short prediction horizon of 100 ms, RI2: longer prediction horizon of walking period) were assessed as communication characteristics. All indices were non-parametrically tested for group differences. Sensitivity and specificity were assessed by bivariate logistic regression models. We found regularity indices systematically dependent on measurement points, information flow horizon and groups. In the patients RI1 was increased, but RI2 was decreased in comparison to the control group. These results quantitatively characterize the altered complex communication in the patients. We conclude that ageing and/or chronic back pain related dysfunctions of gait can advantageously be monitored by gait information flow characteristics of back movements measured as distances between characteristics points at the back surface.

Adult↗
PubMed2004

Exercise-induced changes of motor excitability with and without sensory block.

To explore interactions between the sensory and motor system, we investigated motor excitability changes following a motor exercise with and without an anesthetic block of cutaneous inputs overlying the target muscle. Transcranial magnetic stimulation (TMS) with a focal coil was applied to determine motor output maps, intracortical inhibition (ICI) and intracortical facilitation (ICF) of the first dorsal interosseous muscle (FDI) on both sides. Twelve subjects performed phasic right index finger adductions (frequency: 0.333 Hz) for 30 min. TMS measurements were performed before and after the motor task (Experiment 1). In Experiment 2, median and radial nerve were blocked with Ropivacaine injections at the right wrist prior to the motor exercise. TMS was applied before and after induction of anesthesia and after exercise. In Experiment 3, the same anesthetic block was applied and TMS was performed before and after induction of anesthesia and after additional 30 min of rest. In Experiment 1, right FDI motor output area was enlarged, its center of gravity moved posteriorly, and ICI was reduced after the exercise. In Experiment 2, anesthesia was associated with a shrinkage of right FDI motor output area. After exercise, right FDI motor output area enlarged again but was still significantly smaller than pre-anesthesia. In both experiments, TMS results of left FDI remained unchanged. In Experiment 3, the anesthesia-induced decrease of right FDI motor output area remained unchanged after the period of rest. We conclude that a simple motor task enhanced the cortical representation of the target muscle and reduced intracortical inhibition. An impairment of cutaneous afferents decreased the cortical representation of the target muscle. The decrease of motor excitability induced by the sensory deficit could only partially be reversed by the motor exercise.

Adult↗
PubMed2004

Rapid functional plasticity in the primary somatomotor cortex and perceptual changes after nerve block.

The mature human primary somatosensory cortex displays a striking plastic capacity to reorganize itself in response to changes in sensory input. Following the elimination of afferent return, produced by either amputation, deafferentation by dorsal rhizotomy, or nerve block, there is a well-known but little-understood 'invasion' of the deafferented region of the brain by the cortical representation zones of still-intact portions of the brain adjacent to it. We report here that within an hour of abolishing sensation from the radial and medial three-quarters of the hand by pharmacological blockade of the radial and median nerves, magnetic source imaging showed that the cortical representation of the little finger and the skin beneath the lower lip, whose intact cortical representation zones are adjacent to the deafferented region, had moved closer together, presumably because of their expansion across the deafferented area. A paired-pulse transcranial magnetic stimulation procedure revealed a motor cortex disinhibition for two muscles supplied by the unaffected ulnar nerve. In addition, two notable perceptual changes were observed: increased two-point discrimination ability near the lip and mislocalization of touch of the intact ulnar portion of the fourth finger to the neighbouring third finger whose nerve supply was blocked. We suggest that disinhibition within the somatosensory system as a functional correlate for the known enlargement of cortical representation zones might account for not only the 'invasion' phenomenon, but also for the observed behavioural correlates of the nerve block.

Adult↗
PubMed2004

Acupuncture decreases somatosensory evoked potential amplitudes to noxious stimuli in anesthetized volunteers.

UNLABELLED: The effect of acupuncture on pain perception is controversial. Because late amplitudes of somatosensory evoked potentials (SEPs) to noxious stimuli are thought to correlate with the subjective experience of pain intensity, we designed this study to detect changes of these SEPs before and after acupuncture in a double-blinded fashion. Sixteen volunteers were anesthetized by propofol and exposed to painful electric stimuli to the right forefinger. Then, blinded to the research team, the acupuncture group (n = 8) was treated with electric needle acupuncture over 15 min at analgesic points of the leg, whereas the sham group (n = 8) received no treatment. Thereafter, nociceptive stimulation was repeated. SEPs were recorded during each noxious stimulation from the vertex Cz, and latencies and amplitudes of the N150 and P260 components were analyzed by analysis of variance. P260 amplitudes decreased from 4.40 +/- 2.76 microV (mean +/- SD) before treatment to 1.67 +/- 1.21 microV after treatment (P < 0.05), whereas amplitudes of the sham group remained unchanged (2.64 +/- 0.94 microV before versus 2.54 +/- 1.54 microV after treatment). In conclusion, this double-blinded study demonstrated that electric needle acupuncture, as compared with sham treatment, significantly decreased the magnitudes of late SEP amplitudes with electrical noxious stimulation in anesthetized subjects, suggesting a specific analgesic effect of acupuncture. IMPLICATIONS: This double-blinded study demonstrates that electric needle acupuncture, as compared with sham treatment, significantly decreases the magnitudes of late somatosensory evoked potential amplitudes with electrical noxious stimulation in anesthetized subjects, suggesting a specific analgesic effect of acupuncture.

Adult↗
PubMed2003

Enteral naloxone reduces gastric tube reflux and frequency of pneumonia in critical care patients during opioid analgesia.

OBJECTIVE: Opioid analgesia impairs gastrointestinal motility. Enteral administration of naloxone theoretically allows selective blocking of intestinal opioid receptors caused by extensive presystemic metabolism. Therefore, we studied the effect of enteral naloxone on the amount of gastric tube reflux, the frequency of pneumonia, and the time until first defecation in mechanically ventilated patients with fentanyl analgesia. DESIGN: Prospective, randomized, double-blinded study. SETTING: University hospital intensive care unit. PATIENTS: Eighty-four mechanically ventilated, fentanyl-treated patients without gastrointestinal surgery or diseases. INTERVENTIONS: Patients were assigned to receive 8 mg naloxone or placebo four times daily via a gastric tube during fentanyl administration. MEASUREMENTS AND MAIN RESULTS: Thirty-eight patients received naloxone and 43 placebo; three patients were excluded because of protocol violation. Median gastric tube reflux volume (54 vs. 129 mL, p =.03) and frequency of pneumonia (34% vs. 56%, p =.04) were significantly lower in the naloxone group. In both groups, time until first defecation, ventilation time, and length of intensive care unit stay did not differ. There was no difference in fentanyl requirements between the naloxone and the placebo group (7 vs. 6.5 microg/kg/hr, p =.15). CONCLUSIONS: Our results provide evidence that the administration of enteral opioid antagonists in ventilated patients with opioid analgesia might be a simple-and possibly preventive-treatment of increased gastric tube reflux and reduces frequency of pneumonia.

Administration, Oral↗
PubMed2002

Thyroid hormone response to moderate hypothermia in severe brain injury.

OBJECTIVE: To examine the effect of controlled moderate hypothermia on thyroid response in head-injured patients. DESIGN: Prospective, controlled, randomized study. SETTING: University hospital intensive care unit (ICU). PATIENTS: Twenty-eight patients with severe blunt head injury (Glasgow Coma Scale < or =9). INTERVENTION: Patients were randomly assigned to a hypothermia or a normothermia group. Hypothermia (32-33 degrees C) was induced within 8 h after trauma and maintained for a mean of 36 h. All patients were sedated and mechanically ventilated. MEASUREMENTS AND RESULTS: Thyroid-stimulating hormone( TSH), free and total triiodothyronine (FT3/TT3), reverse triiodothyronine (RT3) and thyroxine (FT4/TT4) were measured during the hypothermia or corresponding normothermia period, after regaining normothermia and 4-6 days later. Of 28 patients included in the study, 11 subjects were treated with hypothermia and 13 patients with normothermia. Four patients had to be excluded. In both groups, serum concentrations of TT3 and FT3 were just below the lower normal range whereas RT3 serum concentrations were near the upper limit of the normal range. TSH serum concentrations were not increased. No statistically significant intra- or inter-group differences were observed. CONCLUSIONS: Thyroid hormone patterns during moderate hypothermia in head-injured patients did not differ from the well known "low T3 state" which is observed in other forms of severe illness.

Adult↗
PubMed2002

Direct influence of mild hypothermia on cytokine expression and release in cultures of human peripheral blood mononuclear cells.

Hypothermia is associated with elevated frequency of infectious complications. Dysfunction of the immune response caused by hypothermia has been demonstrated in both clinical and animal studies, but it still remains unclear to what extent immunocompetent cells are directly influenced by hypothermia. To estimate the direct influence of mild hypothermia on cytokine expression and release by human peripheral blood mononuclear cells (PBMC), primary cultures of PBMC were incubated at 34 degrees C or 32 degrees C activated by lipopolysaccharide (LPS), phytohemagglutinin (PHA), or tumor necrosis factor-alpha (TNF-alpha). The cytokine gene expression was evaluated by RT-PCR. Release of interleukin-2 (IL-2), IL-6, IL-10, and TNF-alpha was measured by ELISA. Mild hyperthermia significantly impaired IL-2 gene expression in PHA-stimulated cultures of PBMC and decreased IL-2 release in all variants of cultures. Secretion of IL-6, IL-10, and TNF-alpha was decreased in hypothermic cultures of PBMC stimulated with the T lymphocyte activator PHA. Slight suppression of IL-10 secretion was observed also in TNF-alpha-stimulated hypothermic cultures of PBMC. TNF-alpha release increased slightly in mild hypothermia control cultures. Our data demonstrate that the direct influence of hypothermia on cytokine expression and release from PBMC is not uniform. Reduction of IL-2 production might play a crucial role in the impairment of immune response in hypothermia.

Cells, Cultured↗
PubMed2000

Oral naloxone reverses opioid-associated constipation.

Opioid-related constipation is one of the most frequent side effects of chronic pain treatment. Enteral administration of naloxone blocks opioid action at the intestinal receptor level but has low systemic bioavailability due to marked hepatic first-pass metabolism. The aim of this study was to examine the effects of oral naloxone on opioid-associated constipation in an intraindividually controlled manner. Twenty-two chronic pain patients with oral opioid treatment and constipation were enrolled in this study. Constipation was defined as lack of laxation and/or necessity of laxative therapy in at least 3 out of 6 days. Laxation and laxative use were monitored for the first 6 days without intervention ('control period'). Then, oral naloxone was started and titrated individually between 3x3 to 3x12 mg/day depending on laxation and withdrawal symptoms. After the 4-day titration period, patients were observed for further 6 days ('naloxone period'). The Wilcoxon signed rank test was used to compare number of days with laxation and laxative therapy in the two study periods. Of the 22 patients studied, five patients did not reach the 'naloxone period' due to death, operation, systemic opioid withdrawal symptoms, or therapy-resistant vomiting. In the 6 day 'naloxone' compared to the 'control period', the mean number of days with laxation increased from 2.1 to 3.5 (P<0.01) and the number of days with laxative medication decreased from 6 to 3.8 (P<0.01). The mean naloxone dose in the 'naloxone period' was 17.5 mg/day. The mean pain intensity did not differ between these two periods. Moderate side effects of short duration were observed in four patients following naloxone single dose administrations between 6 and 20 mg, resulting in yawning, sweating, and shivering. Most of the patients reported mild or moderate abdominal propulsions and/or abdominal cramps shortly after naloxone administration. All side effects terminated after 0.5-6 h. This controlled study demonstrates that orally administered naloxone improves symptoms of opioid associated constipation and reduces laxative use. To prevent systemic withdrawal signs, therapy should be started with low doses and patients carefully monitored during titration.

Administration, Oral↗
PubMedDate not supplied

Painful hallucinations and somatic delusions in a patient with the possible diagnosis of neuroborreliosis.

Neuroborreliosis has become the most frequently recognized tick-borne infection of the nervous system in Europe and the United States. In addition to dermatological, cardiac, articular, and neurologic manifestations, psychiatric disorders such as depression, panic attacks, and schizophrenia-like psychosis can also arise. We report on a 61-year-old woman who developed a severe pain syndrome following several tick bites. She was diagnosed with neuroborreliosis; she received various courses of antibiotics over several years, but without any clinical improvement in her condition. Her eventual admission to a psychiatric ward due to mental symptoms and neuroleptic treatment led to a dramatic improvement of her pain symptoms. However, increasing delusions disclosed a psychotic episode, which ceased over time. We discuss therapeutic difficulties and psychiatric complications in the absence of a clear-cut diagnosis of neuroborreliosis. Although this patient might have suffered from late-onset schizophrenia with painful hallucinations right from the start of her disease, the case highlights psychiatric complications that might be associated with neuroborreliosis.

Antipsychotic Agents↗