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Biomedical subjects

M Riedel

Publications and source records attributed to M Riedel.

At least 19 recordsLinked to original sources
PubMed2007

[Acute and transient psychotic disorders (ICD-10: F23). Empirical data and implications for therapy].

The defining clinical features of acute and transient psychotic disorders (ICD-10: F23) are an acute onset and a duration of psychotic symptoms not exceeding 1-3 months. Previous empirical investigations show that patients with this diagnosis have a favourable prognosis, but also a high risk of relapses (58-77%). The diagnostic stability in the further course of illness seems to be low (34-73%) with a frequent diagnostic change to schizophrenia and affective disorders being observed. As yet, data from controlled clinical trials regarding therapy do not exist. The implications for the treatment of acute and transient psychotic disorders are discussed with this background.

Evidence-Based Medicine↗
PubMed2006

Effects of treatment with the atypical neuroleptic quetiapine on working memory function: a functional MRI follow-up investigation.

BACKGROUND: Working memory as a part of higher-order executive functions is defined by the parallel storage and processing of information. Recent functional fMRI studies have revealed a functional, interregional disintegration of a neuronal network connecting cortical, subcortical and cerebellar regions in schizophrenic patients (SZ). Cognitive impairment in working memory is a core psychopathological correlate of schizophrenic symptoms. Atypical neuroleptics such as quetiapine have shown good efficacy in treating positive and negative symptoms. The presented study evaluated the impact of a neuroleptic steady state treatment with quetiapine on the altered working memory activation patterns in schizophrenia. METHODS: Patients were examined by fMRI at baseline and after 12 weeks of steady state treatment with quetiapine. Matched healthy controls (HC) underwent baseline examination. In the scanner, stimuli were presented in a 2-back and 0-back condition of a working memory (wm) paradigm, whereby a degraded and a non-degraded version were used each time. Additionally, behavioural responses (reaction time to target stimuli and error ratio) were measured. RESULTS: At baseline, healthy controls revealed increased activity in the frontal lobe, especially in regions of the prefrontal cortex. Compared to HC, SZ showed hypoactivation in the right dorsolateral prefrontal cortex (DLPFC) and the ventrolateral prefrontal cortex (VLPFC) bilaterally for the 2-back condition. In the 2-back degraded condition there was a hypoactivation in both, the right DLPFC and the VLPFC. Additionally, patients showed bilaterally decreased activation in the basalganglia in the 2-back and in the right caudatus in the 2-back degraded condition compared to healthy controls. After treatment with quetiapine, patients activations patterns were increased. The pre-post comparison of the 2-back condition revealed a significant increase of activation in the left VLPFC at a significance level of 0.001 (uncorrected). The 2-back degraded condition led to a significant activation pattern in the lingual gyrus and the right precuneus. In both wm conditions, at baseline there were no differences in reaction time but only a worse performance in SZ. After treatment, behavioural measurement of responses, including reaction time and performance, showed slight improvements in SZ, although these did not reach statistical significance. CONCLUSIONS: The neuronal networks underlying working memory are clearly altered in schizophrenia. After 12 weeks of treatment with quetiapine monotherapy, patients showed significant clinical improvement and revealed increased BOLD activity in the VLPFC during a working memory task, although there was no improvement of cognitive performance.

Adult↗
PubMed2006

The cyclooxygenase-2 inhibitor celecoxib has therapeutic effects in major depression: results of a double-blind, randomized, placebo controlled, add-on pilot study to reboxetine.

Signs of an inflammatory process, in particular increased pro-inflammatory cytokines and increased levels of prostaglandine E(2) (PGE(2)), have repeatedly been described in major depression (MD). As cyclooxygenase-2 (COX-2) inhibitors inhibit the PGE(2) production and the production of pro-inflammatory cytokines, we performed a therapeutic trial with the COX-2 inhibitor celecoxib. In a prospective, double-blind, add-on study, 40 patients suffering from an acute depressive episode were randomly assigned to either reboxetine and celecoxib or to reboxetine plus placebo. After a wash-out period, 20 patients received 4-10 mg reboxetine plus placebo and 20 received reboxetine plus 400 mg celecoxib for 6 weeks. The treatment effect was calculated by analysis of variance. There were no significant differences between groups in age, sex, duration or severity of disease or psychopathology, or reboxetine dose or plasma levels. Over 6 weeks, both groups of patients showed significant improvement in scores of the Hamilton Depression Scale. However, the celecoxib group showed significantly greater improvement compared to the reboxetine-alone group. Additional treatment with celecoxib has significant positive effects on the therapeutic action of reboxetine with regard to depressive symptomatology. Moreover, the fact that treatment with an anti-inflammatory drug showed beneficial effects on MD indicates that inflammation is related to the pathomechanism of the disorder, although the exact mechanisms remain to become elucidated.

Adrenergic Uptake Inhibitors↗
PubMed2005

Randomized double blind comparison of olanzapine vs. clozapine on subjective well-being and clinical outcome in patients with schizophrenia.

OBJECTIVE: This randomized double-blind multicenter trial evaluated the effects of olanzapine vs. clozapine on subjective well-being, quality of life (QOL) and clinical outcome. METHOD: The primary objective was to demonstrate non-inferiority of olanzapine, mean dosage 16.2 +/- 4.8 (5-25 mg/day) vs. clozapine, mean dosage 209 +/- 91 (100-400 mg/day) regarding improvement on the 'Subjective Well-Being under Neuroleptic Treatment' (SWN) Scale after 26 treatment weeks in 114 patients with schizophrenia. Secondary outcome parameters included: Munich QOL Dimension List (MLDL), Positive and Negative Symptom Scale (PANSS), Clinical Global Impression (CGI). RESULTS: SWN scores improved significantly in both groups, olanzapine was non-inferior to clozapine (group difference 3.2 points in favor of olanzapine; 95% CI: 4.2;10.5). MLDL-satisfaction, PANSS and CGI-S improved similarly, olanzapine yielded a higher CGI Therapeutic Index. Individual SWN and PANSS changes correlated only moderately (r = -0.45). CONCLUSION: Olanzapine was non-inferior to clozapine. The lack of a marked correlation between PANSS and SWN improvements indicates that patients and psychiatrists perceive treatment differently.

Adolescent↗
PubMed2004

How representative of everyday clinical populations are schizophrenia patients enrolled in clinical trials?

INTRODUCTION: There has been considerable discussion whether clinical trials accurately depict everyday practice. Restrictive inclusion/exclusion criteria, ethical considerations, differences in the severity of psychopathology between clinical and trial patients, or safety issues may bias results, which in turn may rather represent outcome for the "ideal" than for the "average"patient. Therefore, translation into psychiatric practice may be difficult. METHODS: A retrospective case-control study was performed. Schizophrenia inpatients at the LMU Department of Psychiatry, Munich, Germany, who had participated in clinical trials were compared to regular patients serving as controls. Probands and controls were matched by DSM-IV diagnosis, gender and age. The AMDP module, CGI and GAF were used to compare psychopathology. In addition, charts were reviewed for medication dosages, concurrent medical and neurological illness, and clinical history such as age of onset or family history. RESULTS: A total of 200 probands (100/100) were enrolled in the study. With respect to psychopathology, formally thought disordered or suicidal patients were significantly less likely to be study participants (n = 3) than controls (n = 22; p < or = 0.05). Similarly, negative schizophrenia symptoms were significantly less often present in study participants (n = 17) than in controls (n = 38; p < or = 0.05). Study participants were also medically and neurologically healthier than controls. (p = 0.05 respectively). No differences in overall illness severity as depicted by CGI and GAF were observed. CONCLUSION: We found the patients included in our clinical trials representative of the patient encountered in routine clinical practice. Adherence to inclusion and exclusion criteria prevents inclusion of severely ill (e. g. suicidal) patients requiring a more intensive treatment setting. Illness severity was found to be similar in trial participants and controls, and indicates an overall comparably severe psychopathology. The more chronic, rather treatment refractory patients were also not reflected in the trial participant pool; this population may arguably not represent the average clinical patient either. A more careful administration of antipsychotic medication was found in trial participants and may effectively be considered "good clinical practice".

Adult↗
PubMed2004

Surface transfer doping of diamond.

The electronic properties of many materials can be controlled by introducing appropriate impurities into the bulk crystal lattice in a process known as doping. In this way, diamond (a well-known insulator) can be transformed into a semiconductor, and recent progress in thin-film diamond synthesis has sparked interest in the potential applications of semiconducting diamond. However, the high dopant activation energies (in excess of 0.36 eV) and the limitation of donor incorporation to (111) growth facets only have hampered the development of diamond-based devices. Here we report a doping mechanism for diamond, using a method that does not require the introduction of foreign atoms into the diamond lattice. Instead, C60 molecules are evaporated onto the hydrogen-terminated diamond surface, where they induce a subsurface hole accumulation and a significant rise in two-dimensional conductivity. Our observations bear a resemblance to the so-called surface conductivity of diamond seen when hydrogenated diamond surfaces are exposed to air, and support an electrochemical model in which the reduction of hydrated protons in an aqueous surface layer gives rise to a hole accumulation layer. We expect that transfer doping by C60 will open a broad vista of possible semiconductor applications for diamond.

Journal Article↗
PubMed2004

[Quality of life and therapeutic result in outpatients with schizophrenia under flupenthixol treatment].

The objective of this phase IV surveillance study was to document the efficacy and tolerability of flupenthixol as well as the quality of life of patients suffering from schizophrenia and to gain insights into which doses were actually used in specialists outpatients care. The observational variables in this study include demographic variables, details of the diagnosis as well as concomitant diseases. Further evaluations included the assessment of CGI-Scale and subjective patient quality of live assessment using a standardised questionnaire. This questionnaire SWN-K (subjective well-being under neuroleptic treatment; short version) includes 20 items on the state of health with a six-point scale from "absolutely not" to "very strong" respectively. 66.3 % Patients were treated with the depot form of flupenthixol, the rest with oral medication with mean doses of 9.2 mg/d i. m. and 6.3 mg/d p. o. respectively. 78.8 % of patients improved on the CGI-Scale, 5.5 % had an adverse event and in 4.6 % of patients this event was related to the medication. 0.3 % of patients had a serious adverse event. The mean of SWN-K improved from 61.2 to 78.5 in the course of study. The CGI improved from 5.83 to 3.43 in the course of treatment.

Adult↗
PubMed2004

Psychotropic effects of COX-2 inhibitors--a possible new approach for the treatment of psychiatric disorders.

Cyclooxygenase-2 (COX-2)--constitutively expressed in the CNS--is suggested to have an important functional role in the CNS. COX-2 interacts with neurotransmitters such as acetylcholine, serotonin, and glutamate, but is also involved in the regulation of immune system and in inflammation in the central nervous system (CNS) via effects of prostaglandins, in particular prostaglandin E (2). Recently, a role for the new generation of selective COX-2 inhibitors in the treatment of psychiatric disorders is discussed. Until now, COX-2 inhibitors have failed to show therapeutic effects in Alzheimer's disease, but studies from basic research point to a possible effect on cognition. A clinical effect of the COX-2 inhibitor celecoxib on cognition was observed in schizophrenic patients. The therapeutic effect of celecoxib add-on treatment to the atypical antipsychotic risperidone, however, is not restricted to cognition. A general effect on symptoms of schizophrenia was observed, which supports the view that an immunological/inflammatory process is involved in the pathogenesis of schizophrenia. In depression, however, signs of inflammation have been described since many years. Although results of clinical studies with COX-2 inhibitors in depression are still lacking, clinical improvement of a depressive syndrome has been observed in patients, who have been treated with rofecoxib due to other indications. These preliminary clinical data are encouraging for therapeutic effects of the selective COX-2 inhibitors in psychiatric disorders, although these effects have to be confirmed in bigger clinical studies.

Antipsychotic Agents↗
PubMed2004

Zotepine versus placebo in the treatment of schizophrenic patients with stable primary negative symptoms: a randomized double-blind multicenter trial.

BACKGROUND: In contrast to traditional antipsychotic medication, newer, the so called atypical antipsychotic drugs promise to reduce primary negative symptoms in both, acute and chronic schizophrenia and improve quality of life. Zotepine, a D (2)5HT (2A) antagonist, was compared to placebo in this clinical trial to address these issues. METHODS: In an adaptive, 8-week multicenter, double-blind, randomized, parallel group study, efficacy and tolerability as well as influence on quality of life of zotepine and placebo were compared in 80 schizophrenic patients (53 % males, age 41 +/- 11 years) who experienced stable primary negative symptoms. Efficacy was assessed using the PANSS (primary outcome criterion: PANSS negative score), CGI, and MADRS; safety was controlled by EPS (Simpson-Angus Scale), TDRS and adverse events. Quality of life was evaluated with the SF-36 health questionnaire. RESULTS: After eight weeks of treatment with an average dose of 131 +/- 49 mg/day of zotepine, no superior efficacy of zotepine compared to placebo with respect to the PANSS subscale "negative symptoms could be demonstrated. Although patients receiving zotepine showed a pronounced reduction (per protocol set: -7.8 +/- 5.8) during treatment, it was not statistically different from a marked placebo response (-6.5 +/- 5.8). Similar small but not significant differences between zotepine and placebo were found in other subscales of the PANSS, the CGI and the MADRS. With regards to the quality of life assessment, patients under zotepine showed better results in the physical component scale and psychological well-being scale. In general, zotepine was well tolerated and there was no excess of extrapyramidal symptoms compared to placebo. CONCLUSIONS: Zotepine was not superior to placebo in reducing the severity of stable primary negative symptoms in schizophrenic patients in this trial. The main reasons for this finding were a high placebo response in a selected population, a probably too low dose of zotepine, and a short study period. However, several findings show clinical benefit of zotepine therapy in efficacy and quality of life.

Adolescent↗
PubMed2004

Diagnosing pulmonary embolism.

Objective testing for pulmonary embolism is necessary, because clinical assessment alone is unreliable and the consequences of misdiagnosis are serious. No single test has ideal properties (100% sensitivity and specificity, no risk, low cost). Pulmonary angiography is regarded as the final arbiter but is ill suited for diagnosing a disease present in only a third of patients in whom it is suspected. Some tests are good for confirmation and some for exclusion of embolism; others are able to do both but are often non-diagnostic. For optimal efficiency, choice of the initial test should be guided by clinical assessment of the likelihood of embolism and by patient characteristics that may influence test accuracy. Standardised clinical estimates can be used to give a pre-test probability to assess, after appropriate objective testing, the post-test probability of embolism. Multidetector computed tomography can replace both scintigraphy and angiography for the exclusion and diagnosis of this disease and should now be considered the central imaging investigation in suspected pulmonary embolism.

Acute Disease↗
PubMed2004

Pulmonary haemangiosarcoma with main pulmonary artery thrombosis imitating subacute pulmonary embolism with infarction.

We report a patient with subacute pulmonary hypertension caused by unilateral massive pulmonary artery thrombosis due to a pulmonary haemangiosarcoma of the lower lobe with pulmonary arterial and bronchial invasion. The patient was misdiagnosed as having subacute pulmonary embolism and underwent thrombolytic therapy complicated by severe pulmonary haemorrhage. The imaging features of pulmonary artery thrombosis with underlying malignancy and their differential diagnosis are discussed.

Aged↗
PubMed2003

Decreased sTNF-RI in migraine patients?

Tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) have recently been found to have a pain-mediating function in addition to their immunological, proinflammatory function. According to the hypothesis of neurovascular inflammation in migraine, these two cytokines could contribute to migraine pain generation. We analysed IL-6 and its soluble receptors sIL-6R and sgp130 as well as TNF-alpha and its soluble receptor sTNF-RI in 27 migraine patients and eight headache-free controls. Migraine patients tended to have less sTNF-RI (794 +/- 158 pg/ml) than controls (945 +/- 137 pg/ml). No differences in cytokine concentrations were observed. If TNF-alpha plays a role in migraine physiopathology, migraine patients may lack sufficient antagonistic sTNF-RI to neutralize hyperalgesic TNF-alpha during a migraine attack.

Adult↗
PubMed2003

[Paracardiac infiltrate or Turkish sword?].

Four cases of the scimitar syndrome with typical radiologic findings are described. The cases demonstrate that when a curved density along the right paracardial border that descends toward the diaphragm is visible on the posteroanterior chest radiograph, the possibility of an anomalous connection of the pulmonary vein with the inferior vena cava should be considered. The anomaly can remain asymptomatic until adult life.

Adult↗
PubMed2003

[The yellow nail syndrome].

A case of a 54-year-old woman exhibiting the yellow nail syndrome with exudative pleural effusions, lymphoedema, pericardial effusion, rhinosinusitis and bronchiectasis is described. This case illustrates the rather benign course of the syndrome over ten years. A review of the literature is provided. The etiology of the syndrome is obscure, while the pathogenesis seems to involve impaired lymphatic drainage. The entity should be considered in the differential diagnosis of bilateral pleural effusion. It is likely that the condition is not as rare as it appears from the number of published reports, and a greater awareness of its various forms will probably lead to more frequent diagnosis.

Bronchiectasis↗
PubMed2002

[Traveler's thrombosis].

It is pathophysiologically conceivable that prolonged sitting in a tight space (e.g., in airplane or other transport vehicle) may lead to leg vein thrombosis. The association between the incidence of venous thromboembolism and long travel has not been sufficiently documented but seems probable. However, this association is only weak and the incidence of symptomatic thromboembolism much lower than the impression given by the recent publicity. In a healthy person, the risk of suffering a clinically relevant leg vein thrombosis solely because of a flight is extreme low. In persons with risk factors for venous thromboembolism, the flight represents an additional, as yet not quantifiable risk. This risk increases with the duration of the travel. The most important cause of thrombosis during long journeys seems to be venostasis due to relative immobilization. It is not clear whether flight travel represents a higher risk of thrombosis compared to other transport vehicles with comparable duration and immobilization. Until more exact information becomes available, it seems reasonable to recommend simple isometric and isotonic leg exercises during long travel. More aggressive measures must be considered for persons with risk factors for thromboembolism, but these measures should be individualized.

Aircraft↗
PubMed2002

Fibrillary glomerulonephritis associated with crescents as a therapeutic challenge.

Most cases of fibrillary glomerulonephritis (FG) terminate in end-stage renal disease within a few years. We report on two female patients (41 and 50 years old) with the diagnosis of FG associated with crescentic glomerulonephritis, a combination found in 20% to 25% of cases of FG. A broad spectrum of infectious disease and systemic immunologic disorders could be ruled out by specific assays. Both patients had severely impaired renal function, nephrotic syndrome, and hypertension. Based on the biopsy finding with necrotizing FG, treatment was started with corticosteroids and cyclophosphamide. In both patients, renal function recovered markedly within 6 months of treatment, in one case remaining stable for 3.5 years. Whether or not cyclophosphamide treatment changed the course of the FG itself or counteracted the acute crescentic process cannot be determined from these two patients. Based on these promising preliminary findings and the poor prognosis of FG, however, we recommend cyclophosphamide treatment of patients with FG and additional crescentic glomerulonephritis. For a systematic evaluation of the therapeutic options in FG, a multicenter clinical trial should be conducted.

Adrenal Cortex Hormones↗