Maki Ikeda

Associations between sleep disturbance and alcohol drinking: A large-scale epidemiological study of adolescents in Japan

In this study, we attempted to clarify the associations between various sleep disturbance symptoms and the frequency and amount of alcohol use among Japanese adolescents. This study was designed as a cross-sectional sampling survey. A self-administered questionnaire survey was administered to students enrolled in randomly selected junior and senior high schools throughout Japan. A total of 99,416 adolescents responded, and 98,867 questionnaires were subjected to analysis. The prevalence rates of sleep disturbance in the 30 days preceding the day of the survey were as follows: subjectively insufficient sleep (SIS) (boys: 37.6%, girls: 38.7%); short sleep duration (SSD) with less than 6 h of sleep (boys: 28.0%, girls: 33.0%); difficulty initiating sleep (DIS) (boys: 12.5%, girls: 14.1%); difficulty maintaining sleep (DMS) (boys: 10.1%, girls: 10.9%); and early morning awakening (EMA) (boys: 5.1%, girls: 5.0%). Adolescents reporting one or more symptoms of DIS, DMS, and EMA were classified as having insomnia, and its prevalence was 21.5%. The prevalence of each symptom of sleep disturbance increased significantly with the number of days on which alcohol was consumed in the previous 30 days and the amount of alcohol consumed per drinking session (p < 0.01). Multiple logistic regression analyses showed that the adjusted odds ratio (AOR) for each symptom of sleep disturbance, except SIS and EMA, tended to increase with the number of days on which alcohol was consumed and the amount of alcohol consumed per drinking session. The prevalence of sleep disturbance is particularly high among adolescents drinking alcohol. The risk of having each symptom of sleep disturbance, except SIS and EMA, increases with the number of days on which alcohol was consumed and the amount of alcohol consumed per drinking session. These findings reconfirm the need to eliminate underage drinking to ensure good sleep among adolescents.

Epidemiological study of sleep habits among four-and-a-half-year-old children in Japan

BACKGROUND To date, only limited epidemiological data on the sleep habits of young children in Japan have been available. This study used representative samples to examine the sleep habits of four-and-a-half-year-old children in Japan. METHODS We used data from a nationwide cross-sectional survey. A member of each subjects family was asked to complete the questionnaire. The questionnaire included personal characteristics, sleep habits, and lifestyle. RESULTS The data for 39,813 subject children (collection rate: 74.3%) were analyzed. The mean value of total sleep duration, night-time sleep duration, and daytime napping duration was 10 h 40 min 30 s, 9 h 53 min 0 s, and 46 min 24 s, respectively. The prevalence of daytime napping was 45.8%. Those whose total sleep duration was less than 10h accounted for 13.7% of the sample. The factors associated with high odds ratios for shorter total sleep duration were: living in a less populated area, long hours spent watching television, longer maternal work hours, and attending preschool. CONCLUSIONS In attempting to devise ways of improving the sleep habits of young children, the lifestyles of both the children and their parents must be considered.

Disorders of arousal and sleep-related bruxism among Japanese adolescents: a nationwide representative survey.

OBJECTIVE The main objective of our study was to clarify the prevalence of disorders of arousal (confusional arousals, sleepwalking, sleep terrors) and sleep-related bruxism (teeth grinding) and their associated factors among Japanese adolescents. METHODS Our study was designed as a cross-sectional sampling survey. The targets were students attending junior and senior high schools throughout Japan. The questionnaire asked for personal data and information on lifestyle, depressive state, and sleep status including the frequency of experiencing disorders of arousal and sleep-related bruxism. RESULTS A total of 99,416 adolescents responded. The overall response rate was 63.7%, and 98,411 questionnaires were subjected to analysis. The prevalence of disorders of arousal was 7.1% (95% confidence interval [CI], 6.9-7.3%) among boys and 7.7% (95% CI, 7.5-7.9%) among girls. The prevalence of sleep-related bruxism was 2.3% (95% CI, 2.2-2.4%) among boys and 3.0% (95% CI, 2.8-3.2%) among girls. The factors associated with disorders of arousal were the grade in school, smoking habit, alcohol consumption, naptime (min), breakfast habit, participation in club activities, sleep duration, difficulty initiating sleep, nocturnal awakening, early morning awakening, subjective sleep assessment, snoring, decrease in positive feelings, and depression (all p<.001). The factors associated with sleep-related bruxism were gender, smoking habit, nocturnal awakening, snoring, early morning awakening, decrease in positive feelings, and depressive feelings (all p<.001). CONCLUSIONS If disorders of arousal or sleep-related bruxism are observed in an adolescent, his or her smoking habit, alcohol consumption, sleep status, and depressive state should be considered.

Associations of Work Hours and Actual Availability of Weekly Rest Days with Cardiovascular Risk Factors

Associations of Work Hours and Actual Availability of Weekly Rest Days with Cardiovascular Risk Factors: Osamu ITANI, et al. Division of Public Health, Department of Social Medicine, Nihon University School of Medicine—

Irritable bowel syndrome among Japanese adolescents: A nationally representative survey.

No nationally representative survey of irritable bowel syndrome (IBS) among adolescents has ever been performed in Japan. In the present study, we aimed to clarify the prevalence of IBS among Japanese adolescents and the factors associated with it.

Identification of a novel E-box binding pyrrole-imidazole polyamide inhibiting MYC-driven cell proliferation

The MYC transcription factor plays a crucial role in the regulation of cell cycle progression, apoptosis, angiogenesis, and cellular transformation. Due to its oncogenic activities and overexpression in a majority of human cancers, it is an interesting target for novel drug therapies. MYC binding to the E‐box (5′‐CACGTGT‐3′) sequence at gene promoters contributes to more than 4000 MYC‐dependent transcripts. Owing to its importance in MYC regulation, we designed a novel sequence‐specific DNA‐binding pyrrole–imidazole (PI) polyamide, Myc‐5, that recognizes the E‐box consensus sequence. Bioinformatics analysis revealed that the Myc‐5 binding sequence appeared in 5′‐ MYC binding E‐box sequences at the eIF4G1, CCND1, and CDK4 gene promoters. Furthermore, ChIP coupled with detection by quantitative PCR indicated that Myc‐5 has the ability to inhibit MYC binding at the target gene promoters and thus cause downregulation at the mRNA level and protein expression of its target genes in human Burkitts lymphoma model cell line, P493.6, carrying an inducible MYC repression system and the K562 (human chronic myelogenous leukemia) cell line. Single i.v. injection of Myc‐5 at 7.5 mg/kg dose caused significant tumor growth inhibition in a MYC‐dependent tumor xenograft model without evidence of toxicity. We report here a compelling rationale for the identification of a PI polyamide that inhibits a part of E‐box‐mediated MYC downstream gene expression and is a model for showing that phenotype‐associated MYC downstream gene targets consequently inhibit MYC‐dependent tumor growth.

Internet use and problematic Internet use among adolescents in Japan: A nationwide representative survey

Introduction Japan is assumed to have serious health and social problems due to Internet overuse, but little is known about the actual conditions. This study was conducted to investigate the prevalence of problematic Internet use (PIU) and associated Internet use in adolescents in Japan. Methods A nationwide survey of adolescent Internet use was conducted in 2012 and 2013. The participants were 100,050 students from randomly selected junior and senior high schools nationwide who gave valid responses to a self-reported questionnaire. The questionnaire included questions on Internet use and the Japanese version of the Youngs Diagnostic Questionnaire (YDQ) as well as other questions related to lifestyle habits. Internet users were classified by gender according to three categories on the basis of their YDQ scores: adaptive use, maladaptive use, and PIU. Results The estimated prevalence of PIU was 6.2% in males, 9.8% in females, and 7.9% in total; it closely correlated with female gender, school grades, and number of Internet hours. The following common and gender-specific applications that conferred a risk of PIU were identified: downloading (both genders), online gaming (males), social networking services, blogs, and bulletin boards (females). Conclusions A cross-sectional survey using YDQ of a large number of high school students yielded a PIU prevalence of 7.9% in Japan. This study showed that problems associated with Internet overuse have already become serious; therefore, planning and implementation of prevention and control measures is urgently required.

The oncogenic role of GASC1 in chemically induced mouse skin cancer.

AbstractGene amplified in squamous cell carcinoma (SCC) 1 (GASC1), also known as KDM4C/JMJD2C, encodes a histone demethylase that specifically demethylates lysine residues (H3K9, H3K36, and H1.4K26) and plays a crucial role in the regulation of gene expression as well as in heterochromatin formation. GASC1 is located at human chromosome 9p23–24, where frequent genomic amplification is observed in human esophageal cancer, and its aberrant expression is detected in a variety of human cancers, such as breast, colon, and prostate. Therefore, it is highly likely that GASC1 contributes to the genesis and/or development of cancer. However, there is a lack of direct evidence of GASC1 having an oncogenic function. In this study, we aimed to clarify the role of GASC1 in the skin SCC carcinogenesis. For this purpose, we generated Gasc1-heterozygous mice (Gasc1+/−) with reduced expression of Gasc1. On the basis of our results, Gasc1+/− mice displayed a significantly lower incidence and multiplicity of both benign and malignant tumors induced by the two-stage skin carcinogenesis protocol than wild-type mice. In addition, the volume of carcinoma was significantly lower in Gasc1+/− mice. Consistent with these observations, knocking down of Gasc1 resulted in reduced cell viability of SCC cells in vitro. Our findings clearly demonstrated that GASC1 has an oncogenic role in skin carcinogenesis.

Anger and Impulsivity Among Japanese Adolescents: A Nationwide Representative Survey

OBJECTIVE This study aimed to clarify the prevalence of anger and impulsivity and its associated factors through a nationwide survey of junior and senior high school adolescent students in Japan. METHODS A self-administered questionnaire covering (1) personal data, (2) lifestyle, (3) mental health status, and (4) feelings of anger and impulsivity was distributed to junior and senior high school students in Japan. Among the total of 10,955 junior high schools and 5,115 senior high schools nationwide, 130 and 110 were randomly selected, respectively. Of those, 92 junior and 80 senior high schools participated in the survey. The survey period was from December 2008 to the end of January 2009. A total of 95,680 questionnaires were collected. After excluding invalid responses, the remaining 94,777 responses (response rate: 62.3%) were analyzed. RESULTS From the questions regarding anger and impulsivity, 8.7% (95% CI, 8.5%-8.9%) and 7.5% (95% CI, 7.3%-7.7%) of the participants were considered to have experienced intense anger and impulsivity, respectively. Logistic regression analysis indicated that the odds ratios for experiencing intense feelings of anger were significantly higher (all P values < .05) among students who smoked, consumed alcohol, skipped breakfast, did not wish to go to university, had short sleep duration, had decreased positive feelings, had increased depressive feelings, or used mobile phones for longer hours. The odds ratios for experiencing intense impulsivity were significantly higher among students who smoked, consumed alcohol, skipped breakfast, did not participate in club activities, had short sleep duration, had decreased positive feelings, had increased depressive feelings, or used mobile phones for longer hours. CONCLUSIONS The results suggest that healthy lifestyle habits, good sleep habits, and improved mental health are important for preventing intense feelings of anger and impulsivity among adolescents.