Associations of rumination with suicidal ideation and suicide attempts amongst individuals with major depressive disorder: A 12-month longitudinal study in China.

BACKGROUND: This study aimed to explore the longitudinal associations of rumination with suicidal ideation and suicide attempts in individuals with major depressive disorder (MDD). METHODS: Participants were derived from the Depression Cohort in China study (DCC). Those who completed at least one follow-up visit during the 12 months were included in the analysis. Dimensions of rumination including brooding and reflection were each measured using five items of the Ruminative Responses Scale. Suicidal ideation was assessed using the Beck Scale for Suicide Ideation. Suicide attempts were also assessed and all were analyzed with generalized estimating equations. RESULTS: Our final sample included 532 participants aged 18 to 59 years (mean [SD], 26.91 [6.94] years) consisting of 148 (27.8%) males and 384 (72.2%) females. After adjusting for temporal trend and potential confounders, individuals with higher levels of reflection were more likely to report suicidal ideation (AOR =1.11, 95% CI:1.01-1.22). However, no statistically significant association was found between brooding and suicidal ideation (AOR =1.06, 95% CI:0.96-1.17). Conversely, individuals with higher levels of brooding were more likely to report suicide attempts (AOR =1.13, 95% CI:1.02-1.24), while no statistically significant association was observed between reflection and suicide attempts (AOR =0.91, 95% CI:0.82-1.01). CONCLUSION: Rumination reflects a disturbance in cognitive emotional processing and manifests in different dimensions. Our findings suggest that high levels of reflection and brooding may be associated with a higher likelihood of having suicidal ideation and suicide attempts, respectively. However, it should be interpreted with caution, given that effect sizes are small.

Adverse childhood and adulthood experiences and risk of new-onset cardiovascular disease with consideration of social support: a prospective cohort study.

BACKGROUND: The relationship between adverse childhood experiences (ACEs) and adverse adulthood experiences (AAEs) and their association with incident cardiovascular disease (CVD) have not been extensively studied. Considering social support, we evaluated the complex relations of ACEs and AAEs with incident CVD. METHODS: This prospective cohort study used data from the 2014 life course survey and the 2015 and 2018 surveys of the China Health and Retirement Longitudinal Study, a national survey of Chinese adults aged ≥ 45 years from 28 provinces across China. The study population included 5836 individuals (mean [SD] age, 59.59 [8.22] years, 49.7% were males). Information on ACEs, AAEs, young adulthood social support, health behavior factors, health status factors, and demographics was measured. Cox regression models, the difference method to estimate the mediation proportion, and the additive and multiplicative interactions were performed. Subgroup and sensitivity analyses were also conducted. RESULTS: During follow-up, 789 incident cases of CVD occurred. The fully adjusted model, including demographics, health behaviors, health status factors (e.g., depressive symptoms), and social support as control variables, demonstrated that the overall number of ACEs (Hazard ratio [HR]: 1.11, 95% CI: 1.08 to 1.14) and AAEs (HR: 1.19, 95% CI: 1.16 to 1.22) were associated with an increased risk of incident CVD. A dose-response relationship existed between the number of ACEs or AAEs and incident CVD risk. The overall AAEs were found to mediate 17.7% (95% CI: 8.2 to 34.2%) of the association between ACEs and incident CVD. Moreover, a significant additive interaction between ACEs and AAEs was detected (RERI [95% CI]: 0.32 [0.09 to 0.56]). Compared with adults without exposure to both ACE and AAE, those with exposure to both at least one ACE and one AAE indicator had the highest risk of incident CVD (HR: 1.96, 95% CI: 1.72 to 2.23). CONCLUSIONS: Exposure to ACEs or AAEs was independently associated with an increased risk of incident CVD among Chinese middle-aged and older adults in a dose-response manner, and the overall AAEs partially mediated the association between ACEs and incident CVD. Preventive measures aimed at addressing either ACEs or AAEs alone may not significantly reduce the risk of CVD later in life. The necessity of a comprehensive life-course health strategy targeting the prevention of adversity merits increased attention.

Eight-Year Trajectories of Late-Life Loneliness and Incident Dementia: A Nationally Representative Cohort Study.

OBJECTIVE: Some older adults with loneliness might have transient loneliness, followed by full remission, while others might have persistent loneliness. Such different courses might differ in predicting the risk of dementia, but most previous studies assessed short-term loneliness at a single time point, ignoring the long-term changes of loneliness. This study aimed to explore the association between 8-year trajectories of late-life loneliness and incident dementia. METHODS: Data were from the English Longitudinal Study of Ageing (waves 2-9). This study included 6,722 older adults measured for loneliness greater than or equal to three times from wave 2 (2004-2005) to wave 6 (2012-2013) and free from dementia in wave 6. Loneliness was assessed using the short 1980 version of the University of California, Los Angeles Loneliness Scale. Group-based trajectory modeling was used to explore loneliness trajectories during waves 2-6. Cox proportional hazard models were used to investigate the association of loneliness trajectories with incident dementia during waves 6-9. RESULTS: Five distinct loneliness trajectories were identified: long-term low, persistently decreasing, persistently increasing, long-term moderate, and long-term high. Compared with long-term low loneliness, the HRs (95% confidence intervals) for persistently decreasing, persistently increasing, long-term moderate, and long-term high loneliness were 1.29 (0.83-2.00), 1.55 (1.04-2.31), 1.56 (1.03-2.38), and 3.35 (1.89-5.91), respectively. CONCLUSION: The elderly show distinct patterns of loneliness over time, which cannot be captured by a single assessment of loneliness. The elderly with long-term loneliness and persistently increasing loneliness might be the high-risk group for dementia. Further studies are needed to determine whether reducing loneliness can prevent dementia.

Association between academic pressure, NR3C1 gene methylation, and anxiety symptoms among Chinese adolescents: a nested case-control study.

BACKGROUND: Academic pressure is a prevalent stressor among Chinese adolescents and is often linked to anxiety symptoms, although the underlying mechanism remains unclear. This study aimed to investigate the association between NR3C1 gene methylation, academic pressure, and anxiety symptoms among Chinese adolescents. METHODS: This nested-case control study included 150 adolescents (boys: 38.7%; baseline age: 12-17 years) from a school-based longitudinal study of Chinese adolescents. Cases (n = 50) were defined as those with anxiety symptoms at both baseline and follow-up, while controls (n = 100) were randomly selected from those without anxiety symptoms at both timepoints. The cases and controls were 1:2 matched by age. Academic pressure, anxiety symptoms, and potential covariates were measured using a self-report questionnaire. Peripheral whole blood samples were collected from each participant for the detection of cortisol level (i.e., morning serum cortisol level) and DNA methylation. The methylation analysis included a total of 27 CpG units at the NR3C1 promoter region. RESULTS: The final adjusted models showed that students with heavy academic pressure at baseline were at a higher risk of anxiety symptoms at follow-up compared to those with mild academic pressure (ß estimate: 6.24 [95% CI: 3.48 ~ 9.01]). After adjusting for covariates, the methylation level of one CpG unit (NR3C1-16 CpG10) in NR3C1 differed significantly between cases and controls (F = 6.188, P = 0.014), and the difference remained significant after correction for multiple testing (P < 0.025). The adjusted regression models showed that moderate (ß estimate = 0.010 [95% CI: 0.000 ~ 0.020], P = 0.046) and heavy (ß estimate = 0.011 [95% CI: 0.001 ~ 0.020], P = 0.030) academic pressure were significantly associated with the methylation level of NR3C1-16 CpG 10. Further mediation analysis demonstrated that the association of academic pressure and anxiety symptoms was significantly mediated by the methylation of NR3C1-16 CpG 10 (ß estimate for indirect effect = 0.11 [95% CI: 0.005 ~ 0.32]; indirect/total effect = 8.3%). CONCLUSION: The present study suggests that NR3C1-16 CpG 10 DNA methylation might be a potential mechanism that partially explains the lasting effects of academic pressure on subsequent anxiety symptoms among adolescents. Further studies with larger sample sizes are recommended to replicate this finding.

Childhood maltreatment and subsequent depressive symptoms: a prospective study of the sequential mediating role of self-esteem and internalizing/externalizing problems.

BACKGROUND: Depression among adolescents is a seriously disabling public health problem with an extremely high prevalence. Identifying risk factors of depression at an early stage is important to reduce the disease burden. Childhood maltreatment (CM) is one of the major risk factors for depression. The key mediating processes that how CM affects the development of depression, however, still need further clarification. The present study tested the mediating effect of self-esteem, internalizing problems, and externalizing problems between CM and depressive symptoms. Potential sex differences in the foregoing associations were also explored. METHODS: A three-wave longitudinal study was carried out among 1,957 middle and high school students from 69 classes in 10 public schools in the Guangdong province of China. Data collection started when students were in grades 7 and 10 (median age: 13.0, range: 11-18) between January and April 2019, and the students were followed up once a year thereafter. Self-reported CM, depressive symptoms, self-esteem, internalizing and externalizing problems, and other demographics were collected. The multiple serial mediation analysis was conducted. RESULTS: We found that CM was positively related to subsequent internalizing and externalizing problems, as well as depressive symptoms, while self-esteem was negatively related to depressive symptoms. Serial mediation analysis indicated that self-esteem (mediator 1) and internalizing problems (mediator 2) sequentially mediated the path from CM to depressive symptoms in the overall and male population. Moreover, with externalizing problems as mediator 2, self-esteem (mediator 1) acted as a partial mediator in the association between CM and depressive symptoms in males, whereas externalizing problems played a complete mediating role in females. CONCLUSION: Findings revealed that self-esteem and internalizing problems sequentially mediated the influence of CM on depressive symptoms whereas externalizing problems played an independent mediating role. In addition, sex differences need to be taken into consideration when designing prevention and intervention strategies, given the different psychosocial processes between boys and girls.

Global, regional, and national burden of ambient and household PM2.5-related neonatal disorders, 1990-2019.

Previous studies have shown a relationship between fine particulate matter (PM2.5) exposure and an increased risk of neonatal disorders. Considering the huge burden of neonatal disorders, we assessed spatiotemporal trends of neonatal disorders burden caused by ambient and household PM2.5 at the global, regional, and national levels from 1990 to 2019. The number, rate, and population attributable fraction (PAF) of ambient and household PM2.5-related neonatal disorders disability-adjusted life years (DALYs) in 204 countries and territories from 1990 to 2019 were obtained from the Global Burden of Disease Study 2019 to measure the related neonatal disorders burden by age, sex, subtype, and region. Estimated annual percentage change (EAPC) was estimated to quantify temporal trends. In 2019, approximately a fifth of the global neonatal disorders burden was attributable to PM2.5 exposure, with 7.54% for ambient PM2.5 and 13.23% for household PM2.5. Although the global neonatal disorders burden attributable to household PM2.5 has decreased substantially in the past 30 years, that attributable to ambient PM2.5 has increased, especially in lower sociodemographic index (SDI) regions. The highest rate and PAF of ambient PM2.5-related neonatal disorders DALYs in 2019 were in South Asia and East Asia, respectively, and the fastest increases were in Eastern Sub-Saharan Africa (for rate: EAPC = 2.55, 95% CI: 2.37-2.73) and South Asia (for PAF: EAPC = 3.88, 95% CI: 3.68-4.08). In addition, we found an inverted V-shaped between rates and PAFs of ambient PM2.5-related neonatal disorders DALYs in 2019, as well as corresponding EAPCs, and SDI, while rates and PAFs of household PM2.5-related neonatal disorders DALYs in 2019 were highly negatively correlated with SDI. In the past three decades, the global ambient PM2.5-related neonatal disorders burden largely increased, especially in lower SDI regions. Comparatively, the household PM2.5-related neonatal disorders burden decreased but still accounted for about two-thirds of the PM2.5-related neonatal disease burden.

Longitudinal associations between problematic Internet use, self-esteem, and depressive symptoms among Chinese adolescents.

Problematic Internet use (PIU) has a negative impact on self-esteem among adolescents, thereby making them be vulnerable to developing depressive symptoms. However, there is a lack of longitudinal studies focusing on the process. This study aimed to explore the longitudinal associations between PIU, self-esteem, and depressive symptoms. A total of 1,736 adolescents completed this longitudinal study. The baseline survey was conducted in 2019, and the follow-up surveys were performed at 1-year and 2-year later. PIU, self-esteem, and depressive symptoms were measured. A cascade model was used to examine the longitudinal associations between PIU, self-esteem, and depressive symptoms. The mean age of participants was 13.6 (1.5) years at baseline. The final results observed significant within-time associations between PIU, self-esteem, and depressive symptoms at each time point. PIU and low level of self-esteem could predict subsequent depressive symptoms among adolescents, and depressive symptoms were also associated with subsequent PIU and self-esteem. Both PIU and self-esteem show bidirectional predictions with depressive symptoms among Chinese adolescents. Schools and parents should give more attention to adolescents prone to developing depressive symptoms and more social support to reduce their negative emotions. Health-related professionals should incorporate practical knowledge and skills into the education of adolescents to help them better control Internet use, attenuating the risk of future depressive symptoms.

Application of Nicotinamide to Culture Medium Improves the Efficiency of Genome Editing in Hexaploid Wheat.

Histone acetylation is the earliest and most well-characterized of post-translation modifications. It is mediated by histone acetyltransferases (HAT) and histone deacetylases (HDAC). Histone acetylation could change the chromatin structure and status and further regulate gene transcription. In this study, nicotinamide, a histone deacetylase inhibitor (HDACi), was used to enhance the efficiency of gene editing in wheat. Transgenic immature and mature wheat embryos harboring a non-mutated GUS gene, the Cas9 and a GUS-targeting sgRNA were treated with nicotinamide in two concentrations (2.5 and 5 mM) for 2, 7, and 14 days in comparison with a no-treatment control. The nicotinamide treatment resulted in GUS mutations in up to 36% of regenerated plants, whereas no mutants were obtained from the non-treated embryos. The highest efficiency was achieved when treated with 2.5 mM nicotinamide for 14 days. To further validate the impact of nicotinamide treatment on the effectiveness of genome editing, the endogenous TaWaxy gene, which is responsible for amylose synthesis, was tested. Utilizing the aforementioned nicotinamide concentration to treat embryos containing the molecular components for editing the TaWaxy gene, the editing efficiency could be increased to 30.3% and 13.3%, respectively, for immature and mature embryos in comparison to the 0% efficiency observed in the control group. In addition, nicotinamide treatment during transformation progress could also improve the efficiency of genome editing approximately threefold in a base editing experiment. Nicotinamide, as a novel approach, may be employed to improve the editing efficacy of low-efficiency genome editing tools such as base editing and prime editing (PE) systems in wheat.

Academic-related factors and daily lifestyle habits associated with adolescent idiopathic scoliosis: a case-control study.

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is the most prevalent spinal deformity, which may have long-term negative consequences on adolescents. The research on the etiology is of great importance for identifying high-risk population and formulate tailored prevention. This study aimed to evaluate the association between academic-related factors and daily lifestyle habits and AIS. METHODS: In this population-based case-control study, 491 AIS cases and 1,346 healthy controls that frequency-matched by age and sex were recruited in Shenzhen, Southern China. AIS was diagnosed as a Cobb angle ≥ 10° on standing posteroanterior radiographs of the whole spine. The academic-related factors (e.g., reading and writing posture) and daily lifestyle habits (e.g., intake of milk and dairy products) were collected by a self-reported questionnaire. The logistic regression analysis was performed. RESULTS: After adjusting for potential confounding factors, multivariable logistic regression models demonstrated that academic-related factors were associated with AIS. Individuals with poor reading and writing posture were more likely to have AIS (AOR: 2.06, 95%CI: 1.58-2.68). Moreover, there was a significant association between heavy school bags and AIS (AOR: 2.22, 95%CI: 1.50-3.31). Additionally, adolescents who reported daily screen time on weekdays over 2 hours were more likely to develop AIS (P < 0.001). Regarding daily lifestyle habits, individuals without the habit of taking milk and dairy products had a higher risk of developing AIS (AOR: 1.87, 95%CI: 1.29-2.71). CONCLUSIONS: Academic-related factors and daily lifestyle habits were associated with AIS among Chinese adolescents. Schools, families, and related facilities are recommended to take actions on developing effective prevention and management strategies that integrates "Student-Family-School-Education-Health-Sports" for AIS.

Associations of physical activity and screen time with adolescent idiopathic scoliosis.

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is the most common type of idiopathic scoliosis, affecting approximately 0.61%-6.15% adolescents worldwide. To date, the results on the relationship between moderate-to-vigorous physical activity (MVPA) and AIS were inconsistent, and the association between screen time (ST) and AIS remained unclear. This study aimed to describe MVPA and ST among adolescents, and to explore the independent and joint associations between PA, ST, and AIS. METHODS: A frequency-matched case-control study based on the 2021 Chinese School-based Scoliosis Screening Program in Shenzhen city, south China, was conducted. The research involved 494 AIS patients (aged 9-17 years) and 994 sex- and age-matched healthy controls. MVPA and ST were measured using a self-administered questionnaire. Logistic regression models estimated associations between PA, ST, and AIS. RESULTS: Compared to subjects meeting the recommended 60-min daily of MVPA, adolescents reporting daily MVPA time less than 60 min had 1.76 times higher odds of experiencing AIS (95% CI: 1.32-2.35) and adolescents reporting daily MVPA in inactive status had 2.14 times higher odds of experiencing AIS (95% CI: 1.51-3.03). Moreover, participants reporting ST for 2 hours or more had 3.40 times higher odds of AIS compared with those reporting ST less than 2 hours (95% CI: 2.35-4.93). When compared with the adolescents reporting both ST and MVPA meeting the guidelines recommended times (ST < 2 h and MVPA ≥ 60 min/day), those reporting both ST ≥ 2 h and MVPA in inactive status are 8.84 times more likely to develop AIS (95% CI: 3.99-19.61). CONCLUSIONS: This study reported that the insufficient MVPA, especially MVPA in inactive status, and excessive ST were risk factors for AIS. Additionally, the joint effects of insufficient MVPA and excessive ST probably increase the risk of AIS.

The association of FKBP5 gene methylation, adolescents' sex, and depressive symptoms among Chinese adolescents: a nested case-control study.

BACKGROUND: Depressive symptoms among adolescents are a serious health concern around the world. Altered DNA methylation in the FK506 binding protein 5 (FKBP5) gene has been reported to regulate stress response, which has been reported to be closely associated with depressive symptoms. However, most of the contributing studies have been conducted among adults and relatively few studies have considered the effect of disparate social influences and sex differences on the DNA methylation of FKBP5 in persons with depressive symptoms. The present study aimed to test the associations of FKBP5 DNA methylation and depressive symptoms among adolescents and explore possible sex differences in the foregoing associations. METHODS: This study was conducted using a nested case-control design within a longitudinal cohort study from January 2019 to December 2019. Adolescents aged 12 to 17 years from 69 classes in 10 public high schools located in Guangdong province of China participated in this research. Students with persistent depressive symptoms that reported having depressive symptoms at both baseline and follow-up were treated as the case group, and those without depressive symptoms were randomly selected as the control group. Our study finally included 87 cases and 151 controls. Quantitative methylation analyses of the selected gene were carried out by MassARRAY platform System. RESULTS: The overall DNA methylation trend of FKBP5 CpG sites in the case group was lower in comparison to the control group. Compared to healthy controls, lower methylation percentage of FKBP5-12 CpG 1 was observed in adolescents with persistent depressive symptoms after adjusting for covariates (case: 0.94 ± 2.00, control: 0.47 ± 0.92; F = 5.41, P = 0.021), although the statistical significance of the difference was lost after false discovery rate correction (q > 0.05). In addition, the hypomethylation of FKBP5-12 CpG 1 was approaching significance after adjustment for social-environmental factors (aOR = 0.77; P = 0.055), which indicated that no independent association was detected between hypomethylation of FKBP5 CpG sites and persistent depressive symptoms. Furthermore, in the present study, we were unable to identify sex differences in the association of FKBP5 gene methylation with depressive symptoms. CONCLUSION: The decreased methylation level of FKBP5 was observed in adolescents with persistent depressive symptoms, albeit non-significant after correction for multiple testing. Our results presented here are preliminary and underscore the complex gene-environment interactions relevant to the risk for depressive symptoms.

Effects of incentive-based population policies on sustainability of China's recent maternity insurance system reform: a system dynamics simulation.

BACKGROUND: This paper seeks to assess the sustainability of the reformed maternity insurance system and the extent to which China's current maternity insurance system can support different levels of fertility incentives in the future. Our findings will serve as a reference for countries in a similar demographic predicament and those about to face it. METHODS: This study used a combination of qualitative and quantitative methods. In the qualitative assessment, we used a grounded theory model to generalize the factors influencing the sustainability of maternity insurance funds. For the quantitative analysis, we used a novel and comprehensive system dynamics model to visualize the status of the combined operation of maternity and health insurance. Data are mainly derived from the historical data of the Statistical Yearbook of Jiangsu Province and the National Bureau of Statistics of China. RESULTS: In the short term, fertility incentive payments can be set to motivate people to have children. It is therefore recommended that when the scope of the fertility incentive policy is limited to two children, and an average amount above RMB 10 000 could be set, it would be prudent to set the amount at a level not exceeding RMB 10 000 when the scope of the fertility incentive policy is for all newborns. In the long term, a system of incentives for childbirth should be built from education policy, house price regulation, tax relief and childcare services. CONCLUSION: Our research not only highlights the significance of improving the resilience of maternity insurance by combining maternity insurance and health insurance funds, but also suggests a way to economically incentivize beneficiaries to have children so as to mitigate the decline in China's birth rate and cope with the crisis of an ageing population.

Physiological and Transcriptomic Analyses Reveal the Effects of Elevated Root-Zone CO2 on the Metabolism of Sugars and Starch in the Roots of Oriental Melon Seedlings.

Root-zone CO2 is a major factor that affects crop growth, development, nutrient uptake, and metabolism. Oriental melon is affected by root-zone gases during growth, the microstructure, sugar and starch contents, enzymatic activities related to sugar and starch metabolism, and gene expression in the roots of oriental melon seedlings were investigated under three root-zone CO2 concentrations (CK: 0.2%, T1: 0.4%, T2: 1.1%). Elevated root-zone CO2 altered the cellular microstructure, accelerated the accumulation and release of starch grains, disrupted organelle formation, and accelerated root senescence. The sugar and starch contents and metabolic activity in the roots increased within a short duration following treatment. Compared to the control, 232 and 1492 differentially expressed genes (DEGs) were identified on the 6th day of treatment in T1 and T2 plants, respectively. The DEGs were enriched in three metabolic pathways. The majority of genes related to sucrose and starch hydrolysis were upregulated, while the genes related to sucrose metabolism were downregulated. The study revealed that oriental melon seedlings adapt to elevated root-zone CO2 stress by adjusting sugar and starch metabolism at the transcriptome level and provides new insights into the molecular mechanism underlying the response to elevated root-zone CO2 stress.

Associations of FKBP5 polymorphisms and methylation and parenting style with depressive symptoms among Chinese adolescents.

BACKGROUND: Genetic factors may interplay with environmental stressors to contribute to risks of depressive symptoms. This study aimed to investigate the association of FKBP5 polymorphisms and DNA methylation with depressive symptoms among Chinese adolescents, considering the role of parenting style. METHODS: This study used a nested case-control study design based on a cohort study, and the case (n = 120) and control groups (n = 118) were matched with age. Depressive symptoms, parenting style, and other demographics were measured. Fourteen potential polymorphisms and one promoter region in the FKBP5 gene were selected for genotyping and methylation analysis. RESULTS: In the adjusted models, a significant association between FKBP5 rs7757037 and depressive symptoms was found in the codominant model (AG vs. GG; adjusted odds ratio [AOR] = 2.56, 95% CI = 1.13-5.78) and dominant model (AA+AG vs. GG; AOR = 2.38, 95% CI = 1.11-5.120); rs2817032 and rs2817035 polymorphisms were associated with depressive symptoms in the codominant model and dominant model. Significant interactions between rs7757037 and the father's parenting style were found in the codominant model (P = 0.043) and dominant model (P = 0.043), but the gene-environment interactions were not significant after correcting for multiple testing. Moreover, the significant main effects of FKBP5 methylation status on depressive symptoms were not observed, and there was no significant interaction between FKBP5 methylation status and parenting style on depressive symptoms. CONCLUSIONS: Further studies are required to confirm the effect of FKBP5 polymorphisms and methylation as well as their interactions with parenting styles in larger samples.

The Longitudinal Association between Sleep Duration and Suicidal Behavior among Chinese Adolescents: The Role of Nonmedical Use of Prescription Drug.

OBJECTIVE/BACKGROUND: Abnormal sleep and nonmedical use of prescription drugs are known to be factors associated with suicidal behavior, but the nature of the association between weekday sleep duration and suicidal behavior has not been elucidated. Nonmedical use of prescription drugs may play a mediator role in the association mentioned above. PARTICIPANTS: There were a total of 3,273 high school students interviewed at baseline with a response rate of 96.8% and followed up at one year (retention rate, 96.1%). The mean (SD) age of the students was 13.7 (1.0) years. METHODS: Data were drawn from the longitudinal data of the School-based Chinese Adolescents Health Survey. A total of 12 high schools were selected in Guangzhou. Suicidal behavior, weekday sleep duration, and nonmedical use of prescription drugs were measured. RESULTS: Sleeping < 7 hours/day at time 0 was positively associated with suicidal ideation (Adjusted odds ratio [AOR] = 1.51, 95% CI = 1.21-1.89) and suicide attempts (AOR = 2.35, 95% CI = 1.02-5.38) at time 1. The mediation analyses showed that baseline opioids misuse or sedatives misuse partially mediated the associations of baseline short weekday sleep duration with suicidal ideation and suicide attempts at one-year follow-up. CONCLUSIONS: Baseline short weekday sleep duration was positively associated with subsequent suicidal ideation and suicide attempts, and nonmedical use of opioids or sedatives partially mediated the associations mentioned above. Suicidal behavior can be prevented, short weekday sleep duration and nonmedical use of prescription drugs may be risk factors for suicidal behavior, and the respective roles of these factors are needed to be better understood.

A Sheathed Spike Gene, TaWUS-like Inhibits Stem Elongation in Common Wheat by Regulating Hormone Levels.

The elongation and development of wheat (Triticum aestivum L.) stem play an important role in plant architecture. The shortened stem would result in a sheathed spike and a low yield in crops. Unraveling the molecular mechanisms underlying a sheathed spike would be beneficial for plant architecture and yield improvement. We identified a novel gene, TaWUS-like (WUSCHEL-related homeobox-like), which regulated sheathed spike and plant architecture in wheat. The plant height of overexpression transgenic lines was significantly decreased and the spike was not completely elongated and enclosed in flag leaf sheaths. Moreover, the increase in tiller angle resulted in loose plant architecture and lower yield. The statistical and cytological analysis demonstrated that the length of the uppermost and secondary internode was significantly shortened, especially the uppermost internode which was only half the length of the wild-type. The size of parenchyma cells was obviously reduced and cell length on the longitudinal section was elongated insufficiently compared with wild-type. The analysis of hormone content showed that there was a lack of gibberellin A 3 (GA3) in internodes but a higher brassinosteroid (BR) content. TaWUS-like may inhibit the synthesis of GA3 and/or BR, thus affecting the function of signal transduction of these hormones, which further caused stem shortening and plant dwarfing in wheat.

Effects of Elevated Root-Zone CO2 on Root Morphology and Nitrogen Metabolism Revealed by Physiological and Transcriptome Analysis in Oriental Melon Seedling Roots.

Rhizosphere CO2 is vital for crop growth, development, and productivity. However, the mechanisms of plants' responses to root-zone CO2 are unclear. Oriental melons are sensitive to root-zone gas, often encountering high root-zone CO2 during cultivation. We investigated root growth and nitrogen metabolism in oriental melons under T1 (0.5%) and T2 (1.0%) root-zone CO2 concentrations using physiology and comparative transcriptome analysis. T1 and T2 increased root vigor and the nitrogen content in the short term. With increased treatment time and CO2 concentration, root inhibition increased, characterized by decreased root absorption, incomplete root cell structure, accelerated starch accumulation and hydrolysis, and cell aging. We identified 1280 and 1042 differentially expressed genes from T1 and T2, respectively, compared with 0.037% CO2-grown plants. Among them, 683 co-expressed genes are involved in stress resistance and nitrogen metabolism (enhanced phenylpropanoid biosynthesis, hormone signal transduction, glutathione metabolism, and starch and sucrose metabolism). Nitrogen metabolism gene expression, enzyme activity, and nitrogen content analyses showed that short-term elevated root-zone CO2 mainly regulated plant nitrogen metabolism post-transcriptionally, and directly inhibited it transcriptionally in the long term. These findings provided a basis for further investigation of nitrogen regulation by candidate genes in oriental melons under elevated root-zone CO2.

iterClust: a statistical framework for iterative clustering analysis.

Motivation: In a scenario where populations A, B1 and B2 (subpopulations of B) exist, pronounced differences between A and B may mask subtle differences between B1 and B2. Results: Here we present iterClust, an iterative clustering framework, which can separate more pronounced differences (e.g. A and B) in starting iterations, followed by relatively subtle differences (e.g. B1 and B2), providing a comprehensive clustering trajectory. Availability and implementation: iterClust is implemented as a Bioconductor R package. Supplementary information: Supplementary data are available at Bioinformatics online.

Association between nonmedical use of opioids or sedatives and suicidal behavior among Chinese adolescents: An analysis of sex differences.

OBJECTIVE: The rising rate of suicidal behavior among adolescents is a growing concern, and sex differences may induce differential exposure to prescription drug misuse or suicidal behavior. We estimated, among Chinese adolescents, (1) the prevalence of nonmedical use of prescription drugs, suicidal ideation and suicide attempts; (2) whether nonmedical use of prescription drugs was independently associated with suicidal ideation and suicide attempts; and (3) whether there were sex differences in the associations. METHODS: This was a secondary analysis of the data drawn from the 2015 National School-based Chinese Adolescents Health Survey. A total of 94,911 students completed questionnaires and qualified for our survey (response rate: 93.7%). All analyses were conducted separately for boys and girls. RESULTS: There were significant sex differences in the prevalence of opioid or sedative misuse, and the sources and reasons for nonmedical use of prescription drugs ( p < 0.05). The prevalence of suicidal ideation or suicide attempts was significantly higher in girls than in boys (suicidal ideation: 17.9% among girls vs 14.1% among boys; suicide attempts: 3.5% among girls vs 2.7% among boys). Among girls, frequent use of opioids was associated with an increased risk of suicidal ideation (adjusted odds ratio = 1.84, 95% confidence interval = [1.57, 2.17]) and suicide attempts (adjusted odds ratio = 2.96, 95% confidence interval = [2.34, 3.74]), and frequent use of sedatives was also positively associated with suicidal ideation (adjusted odds ratio = 2.23, 95% confidence interval = [1.91, 2.60]) and suicide attempts (adjusted odds ratio = 4.02, 95% confidence interval = [3.25, 4.99]). These associations were also statistically significant in boys, but the magnitudes of adjusted odds ratios for the associations between frequent use of opioids and sedatives and suicidal behavior were greater in girls than boys. CONCLUSION: There exist significant sex differences in the prevalence rates of nonmedical use of prescription drugs and suicidal behavior, and the child's sex plays a role in the association between nonmedical use of prescription drugs and suicidal behavior. The significant sex differences found above may provide a basis for early identification of adolescents at high risk of suicidal behavior.