[Obsessive-Compulsive Symptoms in a Sample of Patients with Chronic Schizophrenia Under Clozapine Treatment]. / Zwangssymptome bei chronisch erkrankten Patienten mit einer Schizophrenie unter Clozapintherapie.

Background: There is a high prevalence of obsessive-compulsive symptoms (OCS) in patients with schizophrenia. Antipsychotic treatment, especially duration and type of substance, is suspected to increase or even cause OCS. Methods: We examined in a naturalistic cross-sectional study the severity of OCS (Obsessive-Compulsive Inventory - Revised) and the incidence of obsessive-compulsive disorder (OCD) according to ICD-10 criteria in 70 patients with schizophrenia. 26 patients were treated with clozapine and 44 patients were treated with another second-generation antipsychotic (SGA). After group matching, the two groups did not differ significantly in age, gender, duration of illness, treatment duration with the current antipsychotic substance and chlorpromazine-equivalent dosage. Results: Patients treated with Clozapine showed a significantly higher rate of OCD (χ2 = 7.304, p = 0.007) and a significantly higher severity of OCS (t = 2.216, p = 0.037) compared to patients treated with another SGA. For the whole sample, duration of treatment with the current antipsychotic medication correlated significantly (p = 0.033, r = 0.323) with the severity of OCS, controlled for duration of illness. However, there was no significant correlation between severity of OCS and duration of illness, controlled for duration of treatment with the current antipsychotic substance. Discussion: Our data suggest an interrelation between the development of OCS or OCD and antipsychotic treatment, especially clozapine. Thereby, duration of treatment is correlated with the severity of OCS, irrespective of the duration of illness.

Apathy in nursing home residents with dementia: results from a cluster-randomized controlled trial.

PURPOSE: Here we evaluate an interdisciplinary occupational and sport therapy intervention for dementia patients suffering from apathy. SUBJECTS AND METHODS: A prospective, controlled, rater-blinded, clinical trial with two follow-ups was conducted as part of a larger cluster-randomized trial in 18 nursing homes in Berlin. n=117 dementia patients with apathy, defined as a score of 40 or more on the apathy evaluation scale (AES) or presence of apathy on the Neuropsychiatric Inventory (NPI), were randomly assigned to intervention or control group. The intervention included 10 months of brief activities, provided once a week. The primary outcome measure was the total score on the AES scale measured directly after the intervention period and again after 12 months. RESULTS: We found significant group differences with respect to apathy during the 10 month intervention period (F2,82=7.79, P<0.01), which reflected an increase in apathy in the control group, but not in the intervention group. Within one year after the intervention was ceased, the treatment group worsened and no longer differed significantly from the control group (P=0.55). CONCLUSIONS: Our intervention was effective for the therapy of apathy in dementia, when applied, but not one year after cessation of therapy.

DTNBP1 (dysbindin) gene variants: in vivo evidence for effects on hippocampal glutamate status.

INTRODUCTION: In linkage and association studies the DTNBP1 gene has been identified as a major susceptibility gene for schizophrenia. Reduced expression of DTNBP1 was found in the hippocampus and prefrontal cortex in post mortem brains of schizophrenic patients. In vitro and animal models provide evidence that the DTNBP1 gene product dysbindin modulates the activity of the neurotransmitter glutamate in hippocampal neurons and is crucial for cell functioning and synaptogenesis. This study is the first to investigate the effects of genetic variants of DTNBP1 on the status of the glutamate system as well as neuronal integrity (N-acetylaspartate, NAA) in the hippocampus and a cortical region, the anterior cingulate cortex (ACC), in humans. METHODS: In 79 healthy subjects, the association of single nucleotide polymorphisms (SNPs) rs760665 and rs909706 with absolute concentrations of glutamate and NAA in the left hippocampus and the ACC were investigated, using proton magnetic resonance spectroscopy (MRS) at 3 Tesla and a well established quantification procedure. RESULTS: Hippocampal glutamate concentration was significantly affected by genotype of rs760665 (F=4.406, df=2,p=0.016) and rs909706 (F=3.171,df=2,p=0.048). For the concentration of NAA, a weak association with rs760665 was observed in the contrast analysis. None of the metabolites measured in the ACC showed a significant connection with either genotype. CONCLUSION: The results support a role of DTNBP1 gene variants in the glutamate neurotransmission system in the human brain at least in the hippocampus. This is compatible to growing evidence of a crucial role of glutamate in the pathobiology of schizophrenia. In addition, the weak association between DTNBP1 genotype and NAA is in line with a regulatory influence of dysbindin on synaptogenesis and neuronal survival.

4-Hydroxynonenal, a lipid peroxidation byproduct of spinal cord injury, is cytotoxic for oligodendrocyte progenitors and inhibits their responsiveness to PDGF.

Oligodendroglial reactions to compression injury of spinal cord include apoptosis, secondary demyelination, and remyelination failure. Within hours after contusion, the membrane lipid peroxidation (MLP) byproduct, 4-hydroxynonenal (HNE), increases rapidly in gray matter and thereafter in white matter tracts beyond the initial lesion level. Considering that HNE is a mediator and marker of neuronal MLP toxicity in various neurodegenerative conditions, the present study examined its effect on the regeneration potential of oligodendrocyte progenitors, as defined by their capacity to survive, proliferate and migrate in primary culture. Treatment of oligodendroblasts with HNE evoked a time- and dose-dependent cytotoxicity resembling apoptosis at aldehyde concentrations known to be produced by neurons and achieved in tissue undergoing peroxidative injury. In addition, sublethal concentrations of HNE inhibited the mitogenic and chemotactic responses of more immature progenitors to platelet-derived growth factor. These effects appear to be mediated in part by the formation of HNE adducts with progenitor proteins located within the plasma membrane and cytoplasmic compartments. Our data are the first to show that HNE can have direct, deleterious effects on oligodendrocyte precursors. The present study also suggests a mechanism by which the striking accumulation of HNE in white matter tracts surrounding the site of spinal cord compression injury and in other ischemic-hypoxic insults associated with MLP could suppress the potential regenerative response of endogenous oligodendrocyte progenitor cells.

The mechanism of recurrence of mouse myeloid leukaemia after total body irradiation and bone marrow transplantation.

RFM mice were X-irradiated (9.5 Gy) 3, 4, 5, 6 or 7 days after inoculation of a transplantable strain-specific myeloid leukaemia (ML) and were reconstituted or not with syngeneic or allogeneic bone marrow cells. Recurrent leukaemia was observed in mice with either type of the bone marrow transplant, indicating that ML cells survived the dose of 9.5 Gy of X-rays. ML cells exposed in vitro to high doses of X-rays (20, 30, 40, 50, 60 Gy) and injected into lethally irradiated syngeneic recipients were still capable of forming leukaemic colonies on the spleens. Higher doses (70, 80, 90 and 100 Gy) abolished the colony formation completely. Irradiated ML cells were also capable of causing leukaemia (hepatosplenomegaly) if inoculated into lethally irradiated CBA mice reconstituted with bone marrow cells of CBA or RFM mice. That was attributed to the release of a leukaemogenic factor from the ML cells, capable of transforming transplanted normal cells.