Genome-wide association analyses of symptom severity among clozapine-treated patients with schizophrenia spectrum disorders.

Clozapine is the most effective antipsychotic for patients with treatment-resistant schizophrenia. However, response is highly variable and possible genetic underpinnings of this variability remain unknown. Here, we performed polygenic risk score (PRS) analyses to estimate the amount of variance in symptom severity among clozapine-treated patients explained by PRSs (R2) and examined the association between symptom severity and genotype-predicted CYP1A2, CYP2D6, and CYP2C19 enzyme activity.

HLA-DQB1 6672G>C (rs113332494) is associated with clozapine-induced neutropenia and agranulocytosis in individuals of European ancestry.

The atypical antipsychotic clozapine is the only effective medication for treatment-resistant schizophrenia. However, it can also induce serious adverse drug reactions, including agranulocytosis and neutropenia. The mechanism by which it does so is largely unknown, but there is evidence for contributing genetic factors.

[Antisocial personality disorder].

Antisocial personality disorder (ASP), especially psychopathy as its extreme form, has provoked fear and excitement over thousands of years. Ruthless violence involved in the disorder has inspired scientists, too.The abundance of research results concerning epidemiology, physiology, neuroanatomy, heritability, and treatment interventions has made ASP one of the best documented disorders in psychiatry.

Exome sequencing followed by large-scale genotyping suggests a limited role for moderately rare risk factors of strong effect in schizophrenia.

Schizophrenia is a severe psychiatric disorder with strong heritability and marked heterogeneity in symptoms, course, and treatment response. There is strong interest in identifying genetic risk factors that can help to elucidate the pathophysiology and that might result in the development of improved treatments. Linkage and genome-wide association studies (GWASs) suggest that the genetic basis of schizophrenia is heterogeneous.

Antipsychotic Polypharmacy in Clozapine Resistant Schizophrenia: A Randomized Controlled Trial of Tapering Antipsychotic Co-treatment.

There is a considerable disparity between clinical practice and recommendations based on meta-analyses of antipsychotic polypharmacy in clozapine resistant schizophrenia. For this reason, we investigated the clinical response to reducing the use olanzapine that had been previously added on clozapine treatment among seriously ill hospitalized patients. In a randomized controlled trial with crossover design, we studied volunteer patients (N=15) who had olanzapine added on to clozapine in a state mental hospital.

Costs of intensive psychiatric care for treatment-resistant minors.

Background: Mental health problems in childhood and adolescence result in high costs to society. Despite the relevance of these problems, there are still relatively few economic evaluations of this domain, in particular the evaluation of the costs of treatment-resistant minors.

Aim Of The Study: The study is aimed to evaluate the costs of mental services use of 52 treatment-resistant minors at the Intensive Psychiatric Care Unit of the Niuvanniemi Hospital, in Kupio, Finland, and the costs of the mental health services used by these patients before their referral to this unit.

Expression of cyclooxygenase-2 is regulated by glycogen synthase kinase-3beta in gastric cancer cells.

Cyclooxygenase-2 (COX-2) expression is a marker of poor prognosis in gastric cancer patients, and its inhibition suppresses gastric tumorigenesis in experimental animal models. The mechanism that leads to COX-2 overexpression in this tumor type is unknown. We have now shown that inhibition of phosphatidylinositol 3-kinase by LY294002 suppresses both basal and phorbol myristate acetate-induced COX-2 expression in TMK-1 and MKN-28 gastric cancer cells.

Topiramate add-on in treatment-resistant schizophrenia: a randomized, double-blind, placebo-controlled, crossover trial.

Objective: We tested the hypothesis that topiramate is more effective than placebo in reducing symptoms in patients with treatment-resistant schizophrenia when combined with ongoing antipsychotic medication.

Method: Twenty-six hospitalized treatment-resistant patients with chronic DSM-IV-diagnosed schizophrenia participated in a randomized, double-blind, placebo-controlled trial in which 300 mg/day of topiramate was gradually added to their ongoing treatment (clozapine, olanzapine, risperidone, or quetiapine) over two 12-week crossover treatment periods. Data were collected from April 2003 to November 2003.

Effects of venlafaxine treatment on clozapine plasma levels in schizophrenic patients.

Depressive symptoms are found at any stage of schizophrenia, and antidepressant medication may be beneficial. Selective serotonin reuptake inhibitor antidepressants have been considered safe in schizophrenia but in combination with clozapine, that is widely used in chronic treatment-resistant schizophrenia, remarkable pharmacokinetic interactions can occur causing an elevation in clozapine plasma levels. To investigate this further, the plasma levels of clozapine were measured in 11 schizophrenic male patients with depressive symptoms who were administered both clozapine and venlafaxine.

Lamotrigine in treatment-resistant schizophrenia: a randomized placebo-controlled crossover trial.

Background: There is no evidence from randomized, controlled trials that demonstrate effectiveness for any pharmacological treatment in clozapine-resistant schizophrenia. Since the introduction of chlorpromazine, all antipsychotics with proven efficacy on positive symptoms have been dopamine antagonists, but recent experimental data suggest that ketamine-induced positive schizophreniform symptoms in healthy subjects can be controlled by a glutamate antagonist lamotrigine. The hypothesis tested was that lamotrigine is more effective than placebo in the treatment of positive schizophrenic symptoms when combined with clozapine.

Ethanol consumption and DRD2 gene TaqI a polymorphism among socially drinking males.

The dopaminergic system in the human brain is thought to play a major role in the development of alcohol consumption habits and alcoholism. It has been reported that homozygous D2-/- knock-out mice lacking D2 receptors consume about 50% to 60% less ethanol than wild-type D2+/+ mice, and heterozygous mice have an intermediate level of alcohol consumption. The DRD2 gene TaqI A polymorphism has been suggested to associate with a low D2 receptor density in post mortem and in vivo measurements.

Analysis of monoamine oxidase A (MAOA) promoter polymorphism in Finnish male alcoholics.

Alterations in monoamine oxidase A (MAOA) expression and enzyme activity may be associated with alcoholism and impulsive behavior. Therefore, functional polymorphisms in the MAOA gene would be good candidates to consider in the interindividual differences that exist in the susceptibility to alcoholism. One variant that has been considered as a candidate in alcoholism is a repeat polymorphism in the MAOA gene promoter.

Lack of association between the functional variant of the catechol-o-methyltransferase (COMT) gene and early-onset alcoholism associated with severe antisocial behavior.

Addictive drugs, including ethanol, increase the brain's dopaminergic transmission, and catechol-o-methyltransferase (COMT) enzyme has a crucial role in dopamine inactivation. A common functional polymorphism in the COMT gene results in a three- to four-fold variation in enzyme activity. In a previous study, we found an association between type 1 (with late-onset but without prominent antisocial behavior) alcoholism and the low activity allele of the COMT gene.

Association between the functional polymorphism of catechol-O-methyltransferase gene and alcohol consumption among social drinkers.

Background: A common functional genetic polymorphism in the catechol-O-methyltransferase (COMT) gene (Val158 Met) results in 3- to 4-fold differences in COMT enzyme activity and dopamine inactivation rate. Previous studies have shown that type I alcoholism is more common among subjects with low activity COMT genotype (LL), compared with high activity (HH) or heterozygotic (LH) genotypes.

Methods: We studied alcohol consumption and the COMT genotype in middle-aged Finnish men (n 896), who represented an unselected ethnically homogenous population sample and reported using alcohol during the past year.

Association between low activity serotonin transporter promoter genotype and early onset alcoholism with habitual impulsive violent behavior.

A common 44-base pair insertion/deletion polymorphism in the promoter region of the human serotonin transporter (5-HTT) gene has been observed to be associated with affective illness and anxiety-related traits. This biallelic functional polymorphism, designated long (L) and short (S), affects 5-HTT gene expression since the S promoter is less active than the L promoter. Since there is strong evidence of a disturbance in brain serotonergic transmission among antisocial, impulsive, and violent type 2 alcoholic subjects, we decided to test the hypothesis that the frequency of the S allele, which is associated with reduced 5-HTT gene expression, is higher among habitually violent type 2 alcoholics when compared with race and gender-matched healthy controls and non-violent late-onset (type 1) alcoholics.

Association between the functional variant of the catechol-O-methyltransferase (COMT) gene and type 1 alcoholism.

Catechol-O-methyltransferase (COMT) is an enzyme which has a crucial role in the metabolism of dopamine. It has been suggested that a common functional genetic polymorphism in the COMT gene, which results in 3 to 4-fold difference in COMT enzyme activity, may contribute to the etiology of mental disorders such as bipolar disorder and alcoholism. Since ethanol-induced euphoria is associated with the rapid release of dopamine in limbic areas, it is conceivable that subjects who inherit the allele encoding the low activity COMT variant would have a relatively low dopamine inactivation rate, and therefore would be more vulnerable to the development of ethanol dependence.

Imaging the structure of the striatum: a fractal approach to SPECT image interpretation.

The spatial pattern of striatal dopamine transporter density in the living human brain was tested by duplicate SPECT scans with [123I]PE2I, [123I]beta-CIT or [123I]beta-CIT-FP and striatal phantom measurements. The resolution-dependent spatial variation was calculated by the fractal analysis of SPECT images. This variation, which depends on the size of the region of interest, was described by the spatial dispersion i.

Pharmacokinetics and dosimetry of iodine-123 labelled PE2I in humans, a radioligand for dopamine transporter imaging.

The iodine-123 labelled selective ligand N-(3-iodoprop-2E-enyl)-2-beta-carbomethoxy-3beta-(4-methylphenyl) nortropane ([123I]PE2I) was evaluated as a probe for in vivo dopamine transporter imaging in the human brain. Six healthy subjects were imaged with a high-resolution single-photon emission tomography scanner. Striatal radioactivity peaked at 1 h after injection.