Genetic Association Analysis of NOS3 and Methamphetamine-Induced Psychosis Among Japanese.

Endothelial nitric oxide synthase (NOS3) is one of the enzymes influencing nitric oxide (NO) function in the human brain. NO is a gaseous neurotransmitter that is involved in a variety of mechanisms in the central nervous system, such as N-methyl-D-aspartate receptor activation and oxidative stress. The evidence from animal pharmacological studies and postmortem studies supports an association between NO and psychotic disorders. Methamphetamine (METH) use disorder is a known psychotic disorder, and we therefore conducted a gene-based case-control study between tagging single nucleotide polymorphisms (SNPs) (rs2070744, rs1799983) in NOS3 and METH-induced psychosis in Japanese subjects (183 with METH-induced psychosis and 267 controls). Written informed consent was obtained from each subject. No significant association was found between any tagging SNP in NOS3 and METH-induced psychosis in the allele/genotype-wise or haplotype-wise analyses. In conclusion, we suggest that NOS3 might not contribute to the risk of METH-induced psychosis in the Japanese population.

Association study of serine racemase gene with methamphetamine psychosis.

Experimental studies have demonstrated that not only dopaminergic signaling but also glutamatergic/NMDA receptor signaling play indispensable roles in the development of methamphetamine psychosis. Our recent genetic studies provided evidence that genetic variants of glutamate-related genes such as DTNBP1, GLYT1, and G72, which are involved in glutamate release and regulation of co-agonists for NMDA receptors, conferred susceptibility to methamphetamine psychosis. Serine racemase converts l-serine to d-serine, which is an endogenous co-agonist for NMDA receptors. Three single nucleotide polymorphisms (SNPs) in the promoter region of the serine racemase gene (SRR), rs224770, rs3760229, and rs408067, were proven to affect the transcription activity of SRR. Therefore, we examined these SNPs in 225 patients with methamphetamine psychosis and 291 age- and sex-matched controls. There was no significant association between methamphetamine psychosis and any SNP examined or between the disorder and haplotypes comprising the three SNPs. However, rs408067 was significantly associated with the prognosis for methamphetamine psychosis and multi-substance abuse status. The patients with C-positive genotypes (CC or CG) of rs408067 showed better prognosis of psychosis after therapy and less abuse of multiple substances than the patients with GG genotypes. Because the C allele of rs408067 reduces the expression of SRR, a lower d-serine level or reduced NMDA receptor activation may affect the prognosis of methamphetamine psychosis and multiple substance abuse. Our sample size is, however, not large enough to eliminate the possibility of a type I error, our findings must be confirmed by replicate studies with larger samples.

Association Between 5HT1b Receptor Gene and Methamphetamine Dependence.

Several lines of evidence implicate serotonergic dysfunction in diverse psychiatric disorders including anxiety, depression, and drug abuse. Mice with a knock-out of the 5HT1b receptor gene (HTR1B) displayed increased locomotor response to cocaine and elevated motivation to self-administer cocaine and alcohol. Previous genetic studies showed significant associations of HTR1B with alcohol dependence and substance abuse, but were followed by inconsistent results. We examined a case-control genetic association study of HTR1B with methamphetamine-dependence patients in a Japanese population. The subjects were 231 patients with methamphetamine dependence, 214 of whom had a co-morbidity of methamphetamine psychosis, and 248 age- and sex-matched healthy controls. The three single nucleotide polymorphisms (SNPs), rs130058 (A-165T), rs1228814 (A-700C) and rs1228814 (A+1180G) of HTR1B were genotyped. There was no significant difference in allelic and genotypic distributions of the SNPs between methamphetamine dependence and the control. Genetic associations of HTR1B were tested with several clinical phenotypes of methamphetamine dependence and/or psychosis, such as age at first abuse, duration of latency from the first abuse to onset of psychosis, prognosis of psychosis after therapy, and complication of spontaneous relapse of psychotic state. There was, however, no asscocation between any SNP and the clinical phenotypes. Haplotype analyses showed the three SNPs examined were within linkage disequilibrium, which implied that the three SNPs covered the whole HTR1B, and distribution of estimated haplotype frequency was not different between the groups. The present findings may indicate that HTR1B does not play a major role in individual susceptibility to methamphetamine dependence or development of methamphetamine-induced psychosis.

Association between the Regulator of G-protein Signaling 9 Gene and Patients with Methamphetamine Use Disorder and Schizophrenia.

The regulator of G-protein signaling (RGS) modulates the functioning of heterotrimeric G protein. RGS9-2 is highly expressed in the striatum and plays a role in modulating dopaminergic receptor-mediated signaling cascades. Previous studies suggested that the RGS9 gene might contribute to the susceptibility to psychotic diseases. Therefore, we investigated the association between the RGS9 gene and two related dopamine psychoses, schizophrenia and methamphetamine use disorders. The subjects comprised 487 patients of schizophrenia and 464 age- and sex-matched healthy controls and 220 patients of methamphetamine use disorder and 289 controls. We genotyped two nonsynonymous polymorphisms, rs12452285 (Leu225Ser) and rs34797451 (His498Arg), of the RGS9 gene. Rs34797451 showed monomorphism in the present Japanese population, but rs12452285 showed polymorphism. There were no significant differences in genotypic or allelic distributions of rs12452285 between patients with schizophrenia and the corresponding control or between patients with methamphetamine use disorder and the corresponding control. We also analyzed the clinical features of methamphetamine use disorder. We found a significant association in allelic distribution with the phenotypes of age at first consumption (p=0.047). The present study suggested that the RGS9 gene is unlikely to play a major role in schizophrenia and methamphetamine dependence liability and/or the development of methamphetamine induced psychosis, at least in a Japanese population.

Association Study of Two Cannabinoid Receptor Genes, CNR1 and CNR2, with Methamphetamine Dependence.

Several studies have suggested that the endocannabinoid system plays significant roles in the vulnerability to psychiatric disorders including drug abuse. To examine the possible association of the CNR1 and CNR2 genes, which encode cannabinoid receptors CB1 and CB2, with methamphetamine dependence, we investigated three single nucleotide polymorphisms (SNPs) (rs806379, rs1535255, rs2023239) in intron 2 of the CNR1 gene and a nonsynonymous SNP, Q63R, in the CNR2 gene. The study samples consisted of 223 patients with methamphetamine dependence and 292 age- and sex- matched controls. There were no significant differences between the patients and controls in genotypic or allelic distribution of any SNP of the CNR1 and CNR2 genes. We also analyzed the clinical features of methamphetamine dependence. Rs806379 of the CNR1 gene showed a significant association with the phenotype of latency of psychosis after the first consumption of methamphetamine. Patients with the T allele or T-positive genotypes (T/T or A/T) may develop a rapid onset of psychosis after methamphetamine abuse. The present study suggests a possibility that genetic variants of the CNR1 gene may produce a liability to the complication of psychotic state after abuse of methamphetamine; however, our findings need to be confirmed by future replications.

Effects of zolpidem on cyclic alternating pattern, an objective marker of sleep instability, in Japanese patients with psychophysiological insomnia: a randomized crossover comparative study with placebo.

OBJECTIVE: A placebo-controlled randomized crossover study to investigate the effects of zolpidem on sleep stability in Japanese insomniac patients was performed using the cyclic alternating pattern (CAP) rate, a polysomnographic marker that reflects sleep instability. METHODS: Seventeen patients (5 M and 12 F, mean age: 40.4+/-13.6 years) who met the International Classification of Sleep Disorders (ICSD) criteria for psychophysiological insomnia were evaluated. During the first period, patients were administered the placebo on the first night, followed by either zolpidem or the placebo on the second night (treatment night). The second crossover period was conducted after a minimum 3-day observation. Improvement in the overnight CAP rate was the primary endpoint. Secondary endpoints included the CAP variables, conventional sleep variables, EEG arousals, subjective evaluation of sleep quality (measured by means of a visual analogue scale and the St. Mary's Hospital Sleep Questionnaire), and drug safety. RESULTS: Zolpidem significantly decreased the overnight CAP rate values (57.6 vs. 39.0%, p=0.009) and improved "sleep depth" (p=0.044) and "sleep quality" (p=0.023) subjective questionnaire scores. Zolpidem also significantly improved VAS (p=0.036). The amount of time spent in sleep stages 3+4 was significantly increased by zolpidem without affecting the amounts of stage 2 and rapid eye movement (REM) sleep. Significant negative correlations were found when the sleep quality score was matched to the CAP rate (p=0.022). No serious adverse events occurred during the study. DISCUSSION: In Japanese patients with psychophysiological insomnia, zolpidem increased sleep stability by significantly improving the overnight CAP rate. Zolpidem also improved sleep depth and sleep quality, both subjectively and objectively.

A polymorphism of DRD2 gene and brain atrophy in methamphetamine psychosis.

Our group, Ujike et al., recently reported that the A1 allele of TaqI A polymorphism of the dopamine receptor D2 (DRD2) gene, associated with transient psychosis, significantly differs from that of patients with prolonged psychosis in methamphetamine psychosis. Therefore, we examined the association between the TaqI A polymorphism of the DRD2 gene and the brain MRI view for patients with methamphetamine psychosis. The subjects underwent brain MRI scans using the FLAIR method. Genotyping was performed by PCR-RFLP methods using genomic DNA extracted from peripheral blood by the phenol method. Ten subjects had the A1/A2 genotype, eleven subjects had the A2/A2 genotype, and no subject had the A1/A1 genotype. The domain size, including the thalamus and basal ganglia that were inside each side of the putamens, did not differ between the three groups (the A1/A2-group, the A2/A2-group, and the young healthy person group). In the comparison based on this domain, the temporal lobe tended to narrow in the A2/A2-group compared to the A1/A2-group (P = .06). The other domain (cerebrum, corpus callosum, etc.) showed no difference between the A1/A2-group and the A2/A2-group. It is suggested that in methamphetamine psychosis the TaqI A polymorphism not only regulates prolongation of psychosis symptoms but also influences the form of the temporal lobe.

Evaluation of Langerhans' cells in human papillomavirus-associated squamous intraepithelial lesions of the uterine cervix.

Current research has been evaluating morphological modifications and density of Langerhans' cells in women with histopathological HPV lesions of the uterine cervix. Fourteen women with subclinical HPV infections underwent clinical, colpocytological colposcopy examinations, and paired biopsies of the uterine cervix. Histopathological, HPV hybrid capture and S-100 immunohistochemical examinations were performed in biopsy specimens. Groupings of viral lesions and normal tissue were analyzed by the Wilcoxon rank-sum test. Langerhans' cells in the specimens were frequently located in the intermediate and basal layers of the epithelium. A significant reduction of cytoplasmic profiles occurred in viral lesions (144.08 profiles/mm2) when compared to normal tissue (256.27 profiles/mm2) of the epithelium. An inverse modulation occurred in the cytoplasmatic profiles/nuclei ratio with 2.80 in viral lesions and 4.89 in normal tissue of the stroma. A local immunodeficiency based on cytoplasmic changes of Langerhans' cells has been postulated as a mechanism by which HPV could be involved in the genesis of neoplasia.

Hypoplasia of primary and permanent teeth following osteitis and the implications of delayed diagnosis of a neonatal maxillary primary molar.

A 2-year-and-6-month-old Japanese girl with delayed eruption of a maxillary right primary canine and disturbance in the development of maxillary right primary molars was examined. The crown of the maxillary right first primary molar was severely decayed and hypoplastic. The periodontal tissues on the maxillary right posterior region were swollen and slight erythrogenic change was observed. Radiographic examination revealed a disturbance in the development of the permanent successor and the primary teeth in the maxillary right quadrant. According to the history, the maxillary right first primary molar had erupted on day seven after birth. It is suggested that the disturbance in development of the permanent successor and the primary teeth was secondary to osteitis caused by infection of the neonatal tooth. Appropriate dental treatment had not been administered for more than two years because the neonatal molar had not been diagnosed.

Examination of accuracy of sleep stages by means of an automatic sleep analysis system 'Sleep Ukiha'.

We examined the differences between the results of an automatic sleep analysis system and inspection decision. Subjects were 10 males (average age 21.6 years). One section consists of 20 s records. The sections that deviated from the algorithm could not be decided. Each sleep stage decided by automatic analysis was compared with the inspection decision. The agreement ratio of stage 3 was 91.6% in the highest, and followed by stage 2, stage 4, stage W and stage 1. The lowest was 62.5% for movement time. The total agreement ratio was 85.8%. The agreement ratios of the apnea index (AI) and the apnea hypopnea index (AHI) were relatively high, but for types of sleep apnea, agreement ratios require improvement.

Study on withdrawal of hypnotics: questionnaire on hypnotic use and its withdrawal.

To investigate the situation and problems contingent to hypnotic use and withdrawal, we conducted a questionnaire of outpatients. Only 41% of the patients were satisfied with their sleep and 53% of the patients took hypnotics. As regards the period, 83% of users had used them for more than 1 year and 19% had used them for more than 10 years. Although 90% of patients perceived efficacy of hypnotics, 67% felt more or less anxious about hypnotic use. Sixty-seven per cent of patients had actually withdrawn from the drugs or decreased dosage before. More than half the patients' conditions worsened after the withdrawal or reducing dosage.

Questionnaire relating to sleep paralysis.

A sleep survey was conducted on 8162 citizens. The cumulative experience rate of sleep paralysis was 39.6%. The initial occurrence of sleep paralysis peaked at age 16 years. In addition to being higher in young people than in older subjects, the incidence of sleep paralysis was also higher among women than among men, and was significantly higher among shift worker than non-shift worker, and among persons engaged in the nursing profession than those not engaged in the nursing profession. The experience rate of sleep paralysis demonstrated a strong correlation with the frequency of dreaming, the experience rate of nightmares, times and regularity of going to bed and waking up, and particularly with the degree of insomnia.

Melatonin therapy for REM sleep behavior disorder.

Rapid eye movement sleep behavior disorder (RBD) is a parasomnia with clinical symptoms that include punching, kicking, yelling and leaping out of bed in sleep. Polysomnographic (PSG) finding showed REM sleep without muscle atonia. Clonazepam is generally used for treating RBD symptoms but melatonin was reported to be effective so we reconfirmed the effect of melatonin on RBD patients in the present study. We used melatonin (3-9 mg/day) which could ameliorate problem sleep behaviors remarkably, as well as %tonic activity in PSG variables. In the present study, melatonin was reconfirmed to be effective in RBD symptoms, especially for patients with low melatonin secretion, while its mechanism was not clearly known in the present study.

Effect of melatonin on sleep and rectal temperature of young healthy evening types.

The present study assessed in healthy nocturnal juveniles the presence or absence of the hypnotic action of exogenous melatonin and its effect on core temperature by oral administration of exogenous melatonin at a pharmacologically low dose 15 min before going to bed at the normal time. Both sleep latency and the number of instances of waking up after falling asleep tended to decrease, while the amount of Stage 2 sleep increased significantly. However, no hypothermic action regarding the rectal temperature for changes in the circadian phase were observed. According to those results, it is possible that exogenous melatonin has some direct hypnotic action on habitual night sleep, although the extent of this action is considered to be relatively weak.

Hypnotic action of melatonin during daytime administration and its comparison with triazolam.

The present study was conducted to assess hypnotic action, effects on rectal temperature and dose dependency by daytime administration of exogenous melatonin (MLT) at 1 mg, 3 mg or 6 mg to subjects consisting of seven healthy juvenile adults. As a result, exogenous MLT significantly increased total sleep time and sleep efficiency, and MLT 6 mg was observed to demonstrate hypnotic effects that were nearly equal to those of triazolam at 0.125 mg. Rectal temperature was significantly decreased at MLT 1mg and 3 mg, there were no significant differences observed in the hypothermic effects at MLT 6 mg. These results indicate that exogenous MLT had dose-dependent hypnotic action on daytime sleep, and it is possible to consider that this hypnotic action was based on a direct-acting mechanism.

Endovascular photodynamic therapy using mono-L-aspartyl-chlorin e6 to inhibit Intimal hyperplasia in balloon-injured rabbit arteries.

BACKGROUND AND OBJECTIVE: Intimal hyperplasia (IH) leading to restenosis is a major complication of arterial revascularization. The purpose of this study was to investigate the effect of photodynamic therapy (PDT) using mono-L-aspartyl chlorin e6 (NPe6) as a photosensitizer and intraluminal radial irradiation for inhibition of IH experimentally. STUDY DESIGN/MATERIALS AND METHODS: Study of laser transmission through the blood indicated that exclusion of blood is a prerequisite for intraluminal PDT. For homogeneous radial laser irradiation to the vessel wall, we used a newly developed cylindrical diffusing balloon laser fiber. Injuries were induced by pulling a balloon catheter through the right iliac artery of rabbits. One and 6 hours after the NPe6 injection (5mg/kg i.v.), drug distribution was examined by fluorescence microscopy. Nineteen rabbits received NPe6 at the time of injuries and PDT was performed with 664-nm laser at 30 and 10 J/cm(2) (20, 30, 40 mW/cm(2)) 1 hour after the injuries. The arteries were harvested at 2 days. In a second group of rabbits, PDT was given at 30 mW/cm(2) (30 J/cm(2)). Two weeks after treatment, the arteries were removed and examined histologically. RESULTS: NPe6 was found to be distributed selectively in the injured media. Endovascular NPe6-PDT showed complete depletion of smooth muscle cells even with 10 J/cm(2) at 2 days. IH was significantly inhibited at 14 days after PDT. CONCLUSIONS: Endovascular PDT of injured artery using NPe6 can prevent IH in this model of arterial wall injury and may become clinically useful for the prophylaxis of IH.

Asymmetry of masticatory muscle activity during the closing phase of mastication.

The purpose of this study was to investigate the asymmetry of masticatory muscle activity between working and nonworking sides in the closing phase during mastication. Fifty adult subjects displaying normal oral function and occlusion participated in this study. Electromyographic (EMG) activity of the anterior temporalis and the superficial masseter muscle were recorded during mastication, simultaneously with motion data of the mandible. EMG activities of elevator muscles and their Asymmetry Index (AI) were analyzed depending on the vertical deviation of the lower incisal point with a two mm gap from the intercuspal position (ICP). EMG activities of both the anterior temporalis and the masseter on the working side were significantly greater than those on the nonworking side. Masseter muscles tended to show greater AI than the anterior temporalis muscles. Thus, asymmetry of the elevator muscles during mastication was a common finding in normal subjects. The normal range of variability of EMG activity and AI was confirmed in each section.

Therapeutic progress of two sibling cases exhibiting sleep-wake rhythm disorder.

In this study, two females, siblings who exhibited a non-24 h sleep-wake rhythm (non-24 h) at home were observed. However, they showed a delayed sleep phase syndrome (DSPS) immediately after admission to Kurume University Hospital. Melatonin (3 mg) was commenced following chronotherapy and this improved their sleep-wake rhythm. Polysomnography (PSG) showed decreased sleep latency and increased sleep stage. In these cases, the involvement of environmental factors was strongly suggested for the sleep-wake rhythm abnormalities as well as familial factors.

Development and application of the 'Sleep Ukiha' automated sleep analysis system.

We attempted to develop an automated sleep analysis system that uses a personal computer as an aid to the entire sleep research process. Analysis is based on electroencephalogram, chin muscle electromyogram and electrooculography, while other physiological phenomena can be handled arbitrarily. Major characteristics of the system include: (i) simultaneous gathering of physiological phenomena from up to three patients; (ii) high-speed waveform analysis; (iii) user-friendly operating environment through the use of a graphical user interface; and (iv) versatile utilization of analytical data in research.

The Koga Hospital Center for studies on sleep: status report.

Between September 1996 and January 1999 we used polysomnography (PSG) to examine 473 patients (involving a total of 662 records). The diagnosis was a sleep-related breathing disorder in 256 patients, including sleep apnea syndrome (SAS) in 194 patients, sleep hypoxicemia in 18 and insomnia in the other four. The SAS consisted of three subtypes: central apnea (CA) in 56 patients, obstructive apnea (OA) in 124 and mixed apnea (MA) in eight. The ratio of central apnea was relatively higher than the national average. Among the 473 patients, the most common complication was heart disease (133 patients) while other complications included hypertension, and respiratory and cerebrovascular diseases. Concerning the therapy for these patients, continuous positive airway pressure therapy was the most commonly applied and was effective in each type of SAS (CA, OA, MA). Other therapies included prosthetic mandibular advancement, bilevel positive airway pressure, medication and ENT operations. In Koga Hospital, there are many patients with heart disease and/or respiratory disease. We examined those patients who presented with snoring and/or apnea using PSG. Among these patients, SAS was the most common sleep disorder. The relative ratio of CA was high and the average age was higher than those with OA.