Factors associated with perceived feasibility and willingness of non-psychiatric doctors in Japan to treat depressed patients.

Objectives: We previously reported that many non-psychiatric doctors in Japan believe that treating depression was not part of their duties. Educational interventions must address motivation of physicians to play a role in depression care. In this study, we explored factors associated with perceived feasibility and willingness of non-psychiatric doctors in Japan to treat depression.

Validity of the Patient Health Questionnaire (PHQ)-9 and PHQ-2 in general internal medicine primary care at a Japanese rural hospital: a cross-sectional study.

Objective: Two depression screening tools, Patient Health Questionnaire (PHQ)-9 and PHQ-2, have not had their validity examined in general internal medicine settings in Japan. We examined the validity of these screening tools.

Methods: A total of 598 outpatients of an internal medicine clinic in a rural general hospital were enrolled consecutively and stratified by PHQ-9 score.

Prevalence of depression among outpatients visiting a general internal medicine polyclinic in rural Japan.

Objective: In Europe and the US, primary care has been anticipated in identifying untreated depression. Findings show a high prevalence of depression in such settings. However, the prevalence of depression in an internal medicine clinic in a rural area of Japan, which has a role in primary care, is unclear.

Attitudes toward depression among Japanese non-psychiatric medical doctors: a cross-sectional study.

Background: Under-recognition of depression is common in many countries. Education of medical staff, focusing on their attitudes towards depression, may be necessary to change their behavior and enhance recognition of depression. Several studies have previously reported on attitudes toward depression among general physicians.

Multiple barriers against successful care provision for depressed patients in general internal medicine in a Japanese rural hospital: a cross-sectional study.

Background: A general internist has an important role in primary care, especially for the elderly in rural areas of Japan. Although effective intervention models for depressed patients in general practice and primary care settings have been developed in the US and UK medical systems, there is little information regarding even the recognition rate and prescription rate of psychotropic medication by general internists in Japan. The present study surveyed these data cross-sectionally in a general internal medicine outpatient clinic of a Japanese rural hospital.

A polymorphism of the metabotropic glutamate receptor mGluR7 (GRM7) gene is associated with schizophrenia.

Introduction: Glutamate dysfunction has been implicated in the pathophysiology of schizophrenia. The metabotropic glutamate receptors (mGluRs) are G-protein-coupled receptors. GRM7, the gene that encodes mGluR7, is expressed in many regions of the human central nervous system.

Autosomal linkage analysis of a Japanese single multiplex schizophrenia pedigree reveals two candidate loci on chromosomes 4q and 3q.

We analyzed a large multiplex schizophrenia pedigree collected in mid-eastern Japan using 322 microsatellite markers distributed throughout the whole autosome. Under an autosomal-dominant inheritance model, the highest pairwise LOD score (LOD = 1.69) was found at 4q (D4S2431: theta = 0.

Monoallelic and unequal allelic expression of the HTR2A gene in human brain and peripheral lymphocytes.

Background: The 102T/C polymorphism of the serotonin 2A receptor (HTR2A) gene is reported to be associated with schizophrenia and other diseases and phenotypes. Altered HTR2A expression has been found in relation to several neuropsychiatric conditions, including depression and schizophrenia. Studies of expression of HTR2A messenger RNA (mRNA) and protein in postmortem brains suggest that the 102C allele might be less transcriptionally active than the T allele.

Genomewide high-density SNP linkage analysis of 236 Japanese families supports the existence of schizophrenia susceptibility loci on chromosomes 1p, 14q, and 20p.

The Japanese Schizophrenia Sib-Pair Linkage Group (JSSLG) is a multisite collaborative study group that was organized to create a national resource for affected sib pair (ASP) studies of schizophrenia in Japan. We used a high-density single-nucleotide-polymorphism (SNP) genotyping assay, the Illumina BeadArray linkage mapping panel (version 4) comprising 5,861 SNPs, to perform a genomewide linkage analysis of JSSLG samples comprising 236 Japanese families with 268 nonindependent ASPs with schizophrenia. All subjects were Japanese.

A polymorphism in the PDLIM5 gene associated with gene expression and schizophrenia.

Background: Results of recent DNA microarray analyses of postmortem brains of patients with schizophrenia revealed that expression of the PDZ and LIM domain 5 gene (PDLIM5) is increased. In the present study, we examined whether polymorphisms in PDLIM5 are associated with schizophrenia.

Methods: We screened for mutations in PDLIM5 in 24 Japanese patients with schizophrenia and evaluated the associations of the identified polymorphisms with schizophrenia in a Japanese case-control population (total samples, 278 schizophrenia patients and 462 control subjects).

Association between chromogranin b gene polymorphisms and schizophrenia in the Japanese population.

Background: We found in previous work a significant association between schizophrenia and D20S95 on chromosome 20p12.3. In this study, we analyzed 10 microsatellite markers and found an association of schizophrenia with D20S882 and D20S905 that flank D20S95.

Possible association between a haplotype of the GABA-A receptor alpha 1 subunit gene (GABRA1) and mood disorders.

Background: The gamma-aminobutyric acid (GABA) neurotransmitter system has been implicated in the pathogenesis of mood disorders. The GABRA1 gene encodes one of the subunits of GABA-A receptor and is located on human chromosome 5q34-q35, which is a region reportedly linked to mood disorders. We examined the GABRA1 gene as a candidate for mood disorders.

Significant linkage to chromosome 22q for exploratory eye movement dysfunction in schizophrenia.

A genome-wide scan for a locus responsible for exploratory eye movement (EEM), which is quantitative and can be disturbed in association with schizophrenia, was performed. A 10-cM resolution genome-wide linkage analysis of the EEM disturbance with 358 highly polymorphic microsatellite markers in 38 nuclear families with 122 members (38 probands, 47 sibs, and 37 parents) including 58 sib-pairs yielded the suggestive linkage to the GCT10C10 marker on chromosome 22q11.2 (LOD = 2.

Lack of evidence for associations between plasma platelet-activating factor acetylhydrolase deficiency and schizophrenia.

Platelet-activating factor (PAF) is a potent phospholipid mediator that plays various roles in neuronal function and brain development. It is involved in NMDA receptor function. Release and degradation of PAF is controlled by intracellular and plasma PAF-acetylhydrolase (PAFAH).

Mutation analysis of the retinoid X receptor beta, nuclear-related receptor 1, and peroxisome proliferator-activated receptor alpha genes in schizophrenia and alcohol dependence: possible haplotype association of nuclear-related receptor 1 gene to alcohol dependence.

Because retinoid cascades are involved in the regulation and development of the central nervous system, including dopaminergic neurons, retinoic acid signaling defects may contribute to schizophrenia and substances dependence. Retinoid X receptors (RXRs) form heterodimer complexes with nuclear-related receptor 1 (NURR1) or with peroxisome proliferator-activated receptors (PPARs). We examined 48 Japanese patients with schizophrenia and 32 patients with alcohol dependence to detect mutations in the retinoid X receptor beta gene (RXRB) on chromosome 6p21.