Comparison between olanzapine and aripiprazole treatment for 104 weeks after hospital discharge in schizophrenia spectrum disorders: a multicenter retrospective cohort study in a real-world setting.

RATIONALE: The long-term effectiveness of olanzapine and aripiprazole in real clinical conditions at flexible doses in patients after hospital discharge has not been evaluated yet. OBJECTIVES: This study was a multicenter retrospective cohort study. Patients with schizophrenia (n = 398) were prescribed olanzapine (n = 303) or aripiprazole (n = 95) at hospital discharge. The continuation of olanzapine or aripiprazole at 26, 52, or 104 weeks after the hospital discharge were compared using a Cox proportional hazards model and adjusted for possible confounders. RESULTS: The Kaplan-Meier survival curves revealed that the continuation of olanzapine at 26 (P = 0.001) and 52 weeks (P = 0.018) was significantly higher than that of aripiprazole but not at 104 weeks. Olanzapine was better than aripiprazole in efficacy at 26 (hazard ratio: 0.321, 95% confidence interval: 0.159-0.645, P = 0.001), 52 (hazard ratio: 0.405, 95% confidence interval: 0.209-0.786, P = 0.008), and 104 weeks (hazard ratio: 0.438, 95% confidence interval: 0.246-0.780, P = 0.005). Aripiprazole was better than olanzapine in tolerability at 104 weeks (hazard ratio: 4.574, 95% confidence interval: 1.415-14.787, P = 0.011). Rates after two years continuation of olanzapine and aripiprazole were not significantly different in patients with less than five years' duration of illness, but olanzapine was more commonly maintained for more than two years in those patients who had been ill for over five years' due to its greater efficacy. CONCLUSION: Olanzapine treatment showed better continuation rates at 26 and 52 after hospital discharge than aripiprazole, whereas maintenance with the two antipsychotics did not differ significantly at 104 weeks, due reduced tolerability of long-term olanzapine treatment.

Intrapancreatic accessory spleen mimicking pancreatic insulinoma with intrapancreatic metastasis in a cat.

An 11-year-old neutered male Domestic Shorthair cat presented with a 3-month history of hypoglycemia, two episodes of seizure, and intermittent tick-like signs. Serum biochemistry revealed severe hypoglycemia associated with high insulin concentrations. Dynamic abdominal computed tomography (CT) indicated two pancreatic masses, which were enhanced most during the late arterial phase but had different degrees and variations of attenuation. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed that one mass was an insulinoma and the other was an ectopic splenic tissue, consistent with the differences in imaging findings. When an intrapancreatic lesion with hyper-attenuation on dynamic abdominal CT is detected, not only insulinoma or metastasis of malignancies but also intrapancreatic accessory spleen (IPAS) should be considered as differential diagnoses.

Two-year effectiveness of risperidone and aripiprazole in the maintenance treatment of patients with recent-onset or chronic schizophrenia and related psychotic disorders: a retrospective multicenter study.

This study aimed to assess the comparative effectiveness of risperidone (RIS) versus aripiprazole (ARP) in patients with recent-onset or chronic schizophrenia during maintenance treatment and to examine the interaction between illness duration and the effectiveness of the treatment. All adult patients with schizophrenia and related disorders discharged from four psychiatric hospitals between 2006 and 2012 were screened and the 2-year continuation rates of monotherapy using RIS or ARP after discharge were examined retrospectively. The treatment continuation of the two drugs in patients with recent-onset (illness duration <5 years) or chronic schizophrenia (illness duration ≥5 years) and the moderator effect of illness duration on the effectiveness of the treatment were analyzed. Of 328 patients, 233 received RIS and 95 received ARP. No significant difference was found between the two drugs in the treatment continuation for the entire sample. However, there was a significant difference favoring ARP in the recent-onset subgroup mainly because of differences in tolerability, whereas RIS tended to present better outcomes in patients with chronic illness. Furthermore, there was a significant variation in the effectiveness of the treatment between recent-onset and chronic schizophrenia. Our results suggest that illness duration is an important moderator in terms of the long-term effectiveness of the two drugs.

Efficacy and safety of tocilizumab in patients with refractory Takayasu arteritis: results from a randomised, double-blind, placebo-controlled, phase 3 trial in Japan (the TAKT study).

OBJECTIVE: To investigate the efficacy and safety of the interleukin-6 receptor antibody tocilizumab in patients with Takayasu arteritis (TAK). METHODS: Patients with TAK who had relapsed within the previous 12 weeks were induced into remission with oral glucocorticoid therapy. In this double-blind, placebo-controlled trial, patients were randomly assigned 1:1 to receive weekly tocilizumab 162 mg or placebo subcutaneously, and oral glucocorticoids were tapered 10 %/week from week 4 to a minimum of 0.1 mg/kg/day until 19 patients relapsed. The primary endpoint was time to relapse of TAK, defined as ≥2 of the following: objective systemic symptoms, subjective systemic symptoms, elevated inflammation markers, vascular signs and symptoms or ischaemic symptoms. RESULTS: The intent-to-treat and safety populations included 18 tocilizumab-treated and 18 placebo-treated patients. The per-protocol set (PPS) included 16 tocilizumab-treated and 17 placebo-treated patients. HRs for time to relapse of TAK were 0.41 (95.41% CI 0.15 to 1.10; p=0.0596) in the intent-to-treat population (primary endpoint) based on relapse in eight tocilizumab-treated and 11 placebo-treated patients and 0.34 (95.41% CI 0.11 to 1.00; p=0.0345) in the PPS. The secondary endpoints, time to relapse assessed by Kerr's definition and clinical symptoms only, were consistent with the primary endpoint. Serious adverse events were reported in one tocilizumab-treated and two placebo-treated patients. There were no serious infections and no deaths. CONCLUSION: Although the primary endpoint was not met, the results suggest favour for tocilizumab over placebo for time to relapse of TAK without new safety concerns. Further investigation is warranted to confirm the efficacy of tocilizumab in patients with refractory TAK. TRIAL REGISTRATION NUMBER: JapicCTI-142616.

Optimal Dosing of Risperidone and Olanzapine in the Maintenance Treatment for Patients With Schizophrenia and Related Psychotic Disorders: A Retrospective Multicenter Study.

OBJECTIVES: This study aims to determine the optimal tolerability dose ranges of risperidone (RIS) and olanzapine (OLZ) administered during schizophrenia maintenance phase. METHODS: Two-year continuation rates of prescription at discharge were examined using a retrospective cohort study method. Adult patients with schizophrenia and related psychotic disorders, receiving antipsychotic monotherapy with RIS or OLZ at discharge, were included. The primary outcome measures were the time to treatment discontinuation and 2-year continuation rates at 4 modal dose ranges of each drug. We estimated the optimal tolerability dose ranges by comparing the continuation rates at various modal doses. RESULTS: Of 648 patients, 344 received RIS and 304 received OLZ. The RIS 2-year continuation rates at 4 daily modal dose ranges were significantly different (0.5-2.5 mg: 46.0%, 3.0-5.0 mg: 40.0%, 5.5-7.5 mg: 30.0%, and 8.0-10.0 mg: 28.0%), with the difference favoring RIS at lower doses (0.5-5.0 mg) more than higher doses (5.5-10.0 mg). In contrast, there were no significant differences among OLZ 4 modal dose ranges (2.5-7.5 mg: 49.1%, 10.0-15.0 mg: 42.6%, 17.5-22.5 mg: 40.9%, and 25.0-30.0 mg: 39.0%). The time to treatment discontinuation significantly favored OLZ over RIS. However, it did not significantly differ between RIS and OLZ at lower doses. CONCLUSIONS: It is suggested that the optimal tolerability dose range during maintenance treatment is 0.5 to 5.0 mg/d for RIS and 2.5 to 30 mg/d for OLZ, and that RIS at lower doses is comparable with OLZ at lower doses.

Low immunogenicity of tocilizumab in patients with rheumatoid arthritis.

OBJECTIVE: Subcutaneous (SC) and intravenous formulations of tocilizumab (TCZ) are available for the treatment of patients with rheumatoid arthritis (RA), based on the efficacy and safety observed in clinical trials. Anti-TCZ antibody development and its impact on safety and efficacy were evaluated in adult patients with RA treated with intravenous TCZ (TCZ-IV) or TCZ-SC as monotherapy or in combination with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs). METHODS: Data from 5 TCZ-SC and 8 TCZ-IV phase III clinical trials and 1 TCZ-IV clinical pharmacology safety study (>50 000 samples) were pooled to assess the immunogenicity profile of TCZ-SC and TCZ-IV (8974 total patients). The analysis included antidrug antibody (ADA) measurement following TCZ-SC or TCZ-IV treatment as monotherapy or in combination with csDMARDs, after dosing interruptions or in TCZ-washout samples, and the correlation of ADAs with clinical response, adverse events or pharmacokinetics (PK). RESULTS: The proportion of patients who developed ADAs following TCZ-SC or TCZ-IV treatment was 1.5% and 1.2%, respectively. ADA development was also comparable between patients who received TCZ monotherapy and those who received concomitant csDMARDs (0.7-2.0%). ADA development did not correlate with PK or safety events, including anaphylaxis, hypersensitivity or injection-site reactions, and no patients who developed ADAs had loss of efficacy. CONCLUSIONS: The immunogenicity risk of TCZ-SC and TCZ-IV treatment was low, either as monotherapy or in combination with csDMARDs. Anti-TCZ antibodies developed among the small proportion of patients had no evident impact on PK, efficacy or safety.

Longterm Safety and Efficacy of Subcutaneous Tocilizumab Monotherapy: Results from the 2-year Open-label Extension of the MUSASHI Study.

OBJECTIVE: To evaluate the longterm safety and efficacy of subcutaneous tocilizumab (TCZ-SC) as monotherapy in patients with rheumatoid arthritis (RA). METHODS: Of 346 patients who received 24 weeks of double-blind treatment with either TCZ-SC monotherapy, 162 mg every 2 weeks (q2w); or intravenous TCZ (TCZ-IV) monotherapy, 8 mg/kg every 4 weeks; 319 patients continued to receive TCZ-SC q2w in the 84-week open-label extension (OLE) of the MUSASHI study (JAPICCTI-101117). Efficacy, safety, and immunogenicity were evaluated for all patients treated with TCZ during 108 weeks. RESULTS: The proportions of patients who achieved American College of Rheumatology 20/50/70 responses, low disease activity [28-joint Disease Activity Score (DAS28) ≤ 3.2], or remission (DAS28 < 2.6) at Week 24 were maintained until Week 108. The incidences of adverse events and serious adverse events were 498.3 and 16.9 per 100 patient-years (PY), respectively. The overall safety of TCZ-SC monotherapy was similar to that of TCZ-IV monotherapy. Rates of injection site reactions (ISR) through 108 weeks remained similar to rates through 24 weeks. ISR were mild and did not cause any patient withdrawals. No serious hypersensitivity events (including anaphylactic reactions) occurred. Anti-TCZ antibodies were present in 2.1% of patients treated with TCZ-SC monotherapy. CONCLUSION: TCZ-SC monotherapy maintained a favorable safety profile and consistent efficacy throughout the 108-week study. Like TCZ-IV, TCZ-SC could provide an additional treatment option for patients with RA.

Sustainable Efficacy of Switching From Intravenous to Subcutaneous Tocilizumab Monotherapy in Patients With Rheumatoid Arthritis.

OBJECTIVE: To evaluate the efficacy and safety of switching from intravenous (IV) tocilizumab (TCZ) to subcutaneous (SC) TCZ monotherapy in rheumatoid arthritis patients. METHODS: Patients who had completed 24 weeks of TCZ-SC (162 mg/2 weeks) or TCZ-IV (8 mg/kg/4 weeks) monotherapy in the double-blind period of the MUSASHI study were enrolled in an 84-week open-label extension period. All received TCZ-SC (162 mg/2 weeks) monotherapy. Effects of the IV to SC switch were evaluated at week 36 (12 weeks after switching). RESULTS: Overall, 319 patients received ≥1 dose of TCZ-SC during the open-label extension period; 160 switched from TCZ-IV to TCZ-SC (TCZ IV/SC) and 159 continued TCZ-SC (TCZ SC/SC). Disease Activity Score in 28 joints using the erythrocyte sedimentation rate clinical remission rates were 62.5% (100 of 160) for TCZ IV/SC and 50.0% (79 of 158) for TCZ SC/SC at week 24, and were maintained at 62.5% (100 of 160) and 57.0% (90 of 158), respectively, at week 36. In the TCZ IV/SC group, 9% of patients (9 of 100) who had achieved remission at week 24 could not maintain remission at week 36. In TCZ IV/SC patients weighing ≥70 kg, the percentage with a sufficient serum TCZ concentration (≥1 µg/ml) decreased from 90.9% (10 of 11) at week 24 to 45.5% (5 of 11) at week 36. Overall safety profiles were similar in TCZ IV/SC and TCZ SC/SC except for mild injection site reactions in TCZ IV/SC. CONCLUSION: Efficacy is adequately maintained in most patients switching from TCZ-IV (8 mg/kg/4 weeks) to TCZ-SC (162 mg/2 weeks) monotherapy. Patients receiving TCZ-IV can switch to TCZ-SC without serious safety concerns. Clinical efficacy may be reduced after switching in some patients with high body weight.

Malignant Hyperthermia during Thoracoscopic Pulmorrhaphy in a 70-Year-Old Man.

Malignant hyperthermia (MH) is a rare but potentially fatal complication that may develop under general anesthesia (GA) and is rarely reported in elderly patients. We encountered a case of mild-onset MH in a 70-year-old patient who was receiving an elective thoracoscopic pulmorrhaphy and had a history of several GA procedures. Anesthesia was induced with propofol, fentanyl, and rocuronium and maintained with sevoflurane and remifentanil. His body temperature (BT) was 37.9°C after induction. During the procedure, the end-tidal CO2 (ETCO2) increased steadily to 47-50 mmHg, presumably in response to the single lung ventilation. At the end, BT was 38.1°C and ETCO2 was 47 mmHg under spontaneous breathing. After extubation, the patient wheezed on inspiration and expiration, and his trachea was reintubated. Sixty minutes after surgery, BT increased to 40.5°C and the arterial blood gas analysis showed severe metabolic acidosis. Based on these findings, MH was suspected and a bolus dose of dantrolene was administered. He responded to the dantrolene, and no complications or recurrence of MH was observed postoperatively. In this patient, the initial signs of MH were so subtle that making the diagnosis of MH was difficult. A high degree of suspicion is necessary to prevent a fulminant MH crisis.

Multiple genetic factors in olanzapine-induced weight gain in schizophrenia patients: a cohort study.

OBJECTIVE: One of the clinically significant adverse effects of olanzapine treatment is weight gain, which shows substantial inter-individual differences and may be influenced by genetic variation. The aim of this investigation was identification of genetic risk factors associated with olanzapine-induced weight gain. METHOD: Inpatients with DSM-IV-TR schizophrenia (N = 164) were administered olanzapine for 8 to 24 (mean +/- SD = 17.9 +/- 9.4) weeks. The clinical background, body mass index (BMI), and clinical response to olanzapine were investigated. Twenty-one loci of diverse candidate genes encoding dopamine, serotonin (5-HT), histamine, and adrenergic receptors, tumor necrosis factor-alpha, ghrelin, adiponectin, and peroxisome proliferator-activated receptor gamma-2, were analyzed. The study was conducted from June 2001 to June 2003 at 4 psychiatric hospitals in Japan. RESULTS: BMI increased by a mean +/- SD 4.3 +/- 10.7% after treatment with olanzapine (mean +/- SD dose = 15.5 +/- 5.8 mg/day). Olanzapine-induced weight gain correlated negatively with baseline BMI and positively with clinical global improvement and the length of olanzapine treatment (p < .0001), but it did not correlate with the daily dose of olanzapine, concomitant antipsychotics, sex, age, or smoking. Four genetic variants, the 102T allele of HTR2A, the 825T allele of GNB3, the 23Cys allele of HTR2C, and the 64Arg/Arg genotype of ADRB3, were significantly associated with olanzapine-induced weight gain. Stepwise regression analysis revealed that the baseline BMI predicted 12.5% of the weight gain, and the 2 latter genetic factors added 6.8%. The patients with double and triple genetic risk factors showed 5.1% and 8.8% BMI increases, respectively, during olanzapine treatment, whereas the patients with a single or no risk factor showed approximately a 1% BMI increase. CONCLUSIONS: We identified genetic variants of 5-HT(2A) and 5-HT(2C) receptors, the G-protein beta-3 subunit, and the adrenergic receptor beta-3, as genetic risk factors for olanzapine-induced weight gain, and they showed additive genetic effects on weight gain.

Genetic variant of prodynorphin gene is risk factor for methamphetamine dependence.

Previous studies have indicated that genetic factors substantially affect development of substance use disorders, including methamphetamine dependence. Prodynorphin (PDYN) is an opioid peptide precursor that yields dynorphins, endogenous kappa opioid-receptor agonists that play important roles in substance abuse. A physiologically active polymorphism of 1-4 repeats of a 68-bp element in the promoter region of the PDYN gene has been identified. We analyzed this polymorphism of the PDYN gene by a case-control association study in 143 patients with methamphetamine dependence and 209 healthy controls in the Japanese population. A 3- or 4-repeat allele in the PDYN gene promoter was found significantly more frequently in patients with methamphetamine dependence than in controls (chi(2)=9.45, p=0.0021). A 3- or 4-repeat allele in the PDYN gene promoter, which was shown to produce significantly higher transcription activity of the PDYN gene than a 1- or 2-repeat allele, is a genetic risk factor for development of methamphetamine dependence (odds ratio: 1.83, 95% CI=1.24-2.68).

The ZDHHC8 gene did not associate with bipolar disorder or schizophrenia.

The zinc finger and DHHC domain-containing protein 8 (ZDHHC8) gene is located on chromosome 22q11, which several genome scans have provided repeated evidence for a significant linkage with bipolar disorder (BPD) and schizophrenia. A recent study revealed that a single nucleotide polymorphism (SNP), rs175174, which has potential effects on splicing, in intron 4 of the ZDHHC8 gene is associated with susceptibility to patients with schizophrenia in US and South Africa. We examined three SNPs of the ZDHHC8 gene, including rs175174, by case-control association in Japanese patients with BPD (N=172) and controls (N=298) or patients with schizophrenia (N=407) and controls (N=497). No significant association with BPD or schizophrenia was observed. After stratification by subcategories, bipolar I and II of BPD, and paranoid and disorganized types of schizophrenia, no significant association was found, nor was a significant association with either disorder found after dividing by gender. These data suggest that the ZDHHC8 gene may not be associated with susceptibility to BPD or schizophrenia, at least in a Japanese population.

The X-box binding protein 1 (XBP1) gene is not associated with methamphetamine dependence.

Bipolar disorder has known as a high risk factor for substance abuse and dependence such as alcohol and illegal drugs. Recently, Kakiuchi et al. reported that the -116C/G polymorphism in the promoter region of the X-box binding protein 1 (XBP-1) gene, which translates a transcription factor specific for endoplasmic reticulum stress caused by misfolded proteins, was associated with bipolar disorders and schizophrenia in a Japanese population. Abuse of methamphetamine often produces affective disorders such as manic state, depressive state, and psychosis resembling paranoid-type schizophrenia. To clarify a possible involvement of XBP-1 in the etiology of methamphetamine dependence, we examined the genetic association of the -116C/G polymorphism of the XBP-1 gene by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism either with methamphetamine dependence or any clinical phenotype of dependence. Because the polymorphism is located in the promoter region of the XBP-1 gene and affects transcription activity of the gene, it is unlikely that dysfunction of XBP-1 may induces susceptibility to methamphetamine dependence.

The GABA type A receptor alpha5 subunit gene is associated with bipolar I disorder.

Several genetic studies have revealed that bipolar disorders are linked with the chromosomal locus of 15q11-q13, where the gamma-aminobutyric acid (GABA) receptor alpha5 subunit gene (GABRA5) locates. GABA is one of the major neurotransmitters that may be involved in the pathogenesis of bipolar disorder. Five polymorphisms in the GABRA5 gene, -754C>T in the promoter region, IVS1-21G>A, IVS2-26T>A, (*)302C>T in 3'-UTR of exon 5, and a CA repeat polymorphism in the 3' flanking region were examined in a Japanese population. IVS1-21G>A exhibited significant differences in the distribution of the genotype and allele frequency in bipolar I disorder patients but not in bipolar II disorder patients, compared with control subjects. The haplotype analysis showed that IVS1-21G>A/IVS2-26A>T was associated with bipolar I disorder, and the IVS1-21A/IVS2-26T haplotype was a negative risk factor for susceptibility to the disorders (odds ratio: 0.57, 95% confidence interval: 0.44-0.73). These results suggest that the GABRA5 gene may confer susceptibility to bipolar I disorder.

A nonsynonymous polymorphism in the human fatty acid amide hydrolase gene did not associate with either methamphetamine dependence or schizophrenia.

Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia.

Preparation, characterization, and application of an enzyme-immobilized magnetic microreactor for flow injection analysis.

Enzyme-immobilized magnetic microparticles (EMMP) have been prepared for use as a microreactor in flow injection analysis (FI). The microparticles were directly injected into the FI system. Their retention occurred within the flow line by small permanent magnets located near the detector. The analytical utility of this concept was illustrated by the assay of glucose using glucose oxidase (GOx), immobilized microparticles, and amperometric detection of liberated hydrogen peroxide. The microparticles were derived from silica gel (nominal pore diameter, 15-80 nm) by impregnation with a citric acid/ethanol solution and a ferric nitrate/ethanol solution and then by calcination in a nitrogen atmosphere to produce ferrimagnetic fine particles of spinel-type iron oxide (gamma-Fe(2)O(3)) inside the pore. They were characterized by X-ray diffraction. The calibration curve of the glucose sample (2 microL injected) was linear between 2.5 x 10(-6) and 5 x 10(-4) mol/L (R = 0.9995), and the detection limit was 1.0 x 10(-6) mol/L or 0.36 ng of injected glucose (S/N = 3). The repeatability for a 5 x 10(-4) mol/L glucose solution was RSD = 1.5% (n = 6). Application to the assay of glucose in a fermentation broth is illustrated. The GOx MMP were stable and active for more than eight months when kept at 10 degrees C.

The human frizzled-3 (FZD3) gene on chromosome 8p21, a receptor gene for Wnt ligands, is associated with the susceptibility to schizophrenia.

Neurodevelopmental abnormalities have been reported in studies on the pathogenesis of schizophrenia. The Wnt-signaling pathway has been implicated in a variety of processes in neurodevelopment, and the frizzled proteins have been identified as receptors for Wnt ligands. Of the frizzled proteins, frizzled-3 (FZD3) is required for formation of the neural crest and for development of major fiber tracts in the CNS. The human FZD3 gene is located on chromosome 8p21, a positive linkage locus for schizophrenia. We analyzed polymorphisms of the FZD3 gene in patients with schizophrenia and control subjects in the Japanese population. We found a significant association between schizophrenia and the FZD3 gene in single nucleotide polymorphisms and haplotype analyses. Our data suggest that dysregulation of the Wnt-signaling pathway may be involved in the susceptibility to schizophrenia.

No association between the sigma receptor type 1 gene and schizophrenia: results of analysis and meta-analysis of case-control studies.

BACKGROUND: Several lines of evidence have supported possible roles of the sigma receptors in the etiology of schizophrenia and mechanisms of antipsychotic efficacy. An association study provided genetic evidence that the sigma receptor type 1 gene (SIGMAR1) was a possible susceptibility factor for schizophrenia, however, it was not replicated by a subsequent study. It is necessary to evaluate further the possibility that the SIGMAR1 gene is associated with susceptibility to schizophrenia. METHODS: A case-control association study between two polymorphisms of the SIGMAR1 gene, G-241T/C-240T and Gln2Pro, and schizophrenia in Japanese population, and meta-analysis including present and previous studies. RESULTS: There was no significant association of any allele or genotype of the polymorphisms with schizophrenia. Neither significant association was observed with hebephrenic or paranoid subtype of schizophrenia. Furthermore, a meta-analysis including the present and previous studies comprising 779 controls and 636 schizophrenics also revealed no significant association between the SIGMAR1 gene and schizophrenia. CONCLUSION: In view of this evidence, it is likely that the SIGMAR1 gene does not confer susceptibility to schizophrenia.

No association between the dihydropyrimidinase-related protein 2 (DRP-2) gene and bipolar disorder in humans.

Several susceptibility loci for both of schizophrenia and bipolar disorder (BPD) have been found to overlap on several chromosomes including 8p21. Expression of dihydropyrimidinase-related protein 2 (DRP-2), which gene is located on 8p21, was found to be reduced in the brains of individuals with schizophrenia and BPD. Recently, we demonstrated a significant association between the DRP-2 gene and schizophrenia. Based on the rationale, we investigated the genetic association of the DRP-2 gene with BPD using a case-control study in the Japanese population. However, no significant associations were found between five polymorphisms of the DRP-2 gene (-975C>G, 352G>A, 426C>T, 1506T>C, and *2236T>C), and BPD, nor were associations detected between either of the polymorphisms and any subtype of BPD, bipolars I and II. The present study did not provide any evidence for a contribution of the DRP-2 gene to susceptibility to BPD.

Association study of the brain-derived neurotrophic factor (BDNF) gene with bipolar disorder.

Brain-derived neurotrophic factor (BDNF) belongs to a family of neurotrophic factors and has been demonstrated to promote the survival, differentiation, and maintenance of a broad variety of central nervous system neurons. Several reports have suggested that the BDNF gene is a plausible functional candidate gene underlying the predisposition for developing bipolar disorder (BPD). In the present study, we investigated the possible role of the BDNF gene in the etiology of BPD using a matched case-control association design in a Japanese population. There was no evidence for an allelic or genotypic association of two polymorphisms (-1360C>T and 196G>A) of the BDNF gene with BPD. Furthermore, no significant association was observed between these polymorphisms and either of two diagnostic subtypes (bipolars I and II disorder). The results suggest that the BDNF gene is unlikely to confer susceptibility to BPD.