The associations of secondhand smoke exposure with neurodevelopmental disorders and critical time window identification: A systematic review and meta-analysis.

BACKGROUND: Secondhand smoke (SHS) exposure was harmful for brain development. However, the association between SHS exposure and NDDs diagnosis were unclear. OBJECTIVES: To evaluate associations between SHS exposure and NDDs diagnosis, identify critical time windows, and summarize the strength of evidence. METHODS: To investigate the associations of SHS exposure and the development of NDDs, we searched Ovid, EMBASE, Web of Science, Cochrane Library, and PubMed for all the relevant studies up to 31 March 2023. The risk estimates and standardized mean differences (SMD) for the individuals with any NDDs who were exposed to SHS exposure compared with those unexposed or low-exposed. RESULTS: The results showed that a total of 31,098 citations were identified, of which 54 studies were included. We identified significant associations between SHS exposure and the risks of NDDs including specific types of NDDs like attention deficit hyperactivity disorder (ADHD) and learning disabilities (LD) despite the observed heterogeneity for NDDs and ADHD. We also observed a significant association between cotinine exposure and ADHD. However, inconsistent ratings between the two quality-of-evidence methods for all the meta-analyses indicated the current evidence of the associations and the potential exposure window remained inconclusive. DISCUSSION: Our findings suggested that SHS exposure was associated with a higher risk of developing ADHD and LD, with inconclusive quality-of-evidence. In addition, period-specific associations remained unclear based on current evidence.

Sports motivation in Chinese college students: A systematic review.

Background: According to the 2014 National Physical Fitness and Health Monitor, people aged 9 to 22 exhibit limited physical activity, with a large proportion exercising for less than 1 h daily. China has focused on the study of college student sports motivation. This study comprehensively analyzed sports motivation studies and their relevant factors on Chinese college students. Methods: The researchers searched CNKI (China National Knowledge Infrastructure), WANFANG DATA, Cqvip, Scopus, Web of Science, PubMed, and Cochrane Library for sports motivation in Chinese college students. Articles from 2018 to 2023 were searched. The final analysis included 30 pieces of literatures that met the topic criteria. Results: The results show that Chinese college students' sports motivation studies used large sample sizes and covered most of China. The main sports motivations are health, shape, and relaxation. Demography, psychology, social support, physical environment, and policy aspects affect sports motivation. Lack of use of qualitative and longitudinal studies. Conclusion: In the future, scholars who research the sports motivation of Chinese college students need to pay more attention to social support, physical environment, and policy. Furthermore, scholars may try to use qualitative and longitudinal studies.

Infant feeding practices and autism spectrum disorder in US children aged 2-5 years: the national survey of children's health (NSCH) 2016-2020.

OBJECTIVE: To investigate the relationship between infant feeding practices and autism spectrum disorder (ASD) among children aged 2-5 years in the United States (US). METHODS: Data from the 2016-2020 National Survey of Children's Health, a nationally representative cross-sectional survey, were utilized for this study. Questionnaires were administered to parents of children aged 2-5 years to gather information on ASD diagnosis, infant feeding practices, and demographic factors (e.g., child sex, ethnic group, and maternal age at birth). Logistic regression with sample weights was employed to assess the association between infant feeding practices and ASD, while controlling for demographic variables. Polynomial regression models were used to examine trends in exclusive breastfeeding and ever breastfeeding rates among children with and without ASD. RESULTS: A total of 35,050 children aged 2-5 years were analyzed, including 616 diagnosed with ASD, after excluding participants with missing information on breastfeeding and ASD diagnosis. Of these children with ASD, 76.6% (n = 472) had a breastfeeding history, with 67.5% (n = 416) engaged in partial breastfeeding and 9.1% (n = 56) exclusively breastfed. Adjusted odds ratios for each additional month of breastfeeding compared to never being breastfed were 0.98 (95% CI, 0.96-1.01). The adjusted odds ratios for breastfeeding durations of > 0-6 months, > 6-12 months, > 12-24 months, and > 24 months were 0.81 (95% CI, 0.50-1.31), 0.65 (95% CI, 0.36-1.18), 0.81 (95% CI, 0.44-1.49), and 0.48 (95% CI, 0.23-1.01), respectively. Compared to children who were never breastfed, the adjusted odds ratio for children who were ever breastfed was 0.74 (95% CI, 0.47-1.18). Among children with ASD, the proportion of ever breastfeeding declined from 82.0% in 2017 to 64.3% in 2020, while exclusive breastfeeding decreased from 12.0% in 2016 to 4.2% in 2020. CONCLUSIONS AND RELEVANCE: Although no significant association was found between infant feeding practices and ASD among US children aged 2-5 years, the rates of breastfeeding, particularly exclusive breastfeeding, were suboptimal among children with ASD. This highlights the need for specific policies and practices to promote and support breastfeeding among parents of children with ASD or those at high risk of having a child with ASD.

The economic impacts of COVID-19 and city lockdown: Early evidence from China.

As the first major developing country heavily struck by the COVID-19 pandemic, China adopted the world's most stringent lockdown interventions to contain the virus spread. Using macro- and micro-level data, this paper shows that both the pandemic and lockdown policies have had negative and significant impacts on the economy. Gross regional product (GRP) fell by 9.5 and 0.3 percentage points in cities with and without lockdown interventions, respectively. These impacts represent a dramatic recession from China's average growth of 6.74% before the pandemic. The results indicate that lockdown explains 2.8 percentage points of the GDP loss. We also document significant spill-over effects of the pandemic in adjacent areas but no such effects of lockdown. Reduced labor mobility, land supply, and entrepreneurship are among the most significant mechanisms underpinning the impacts of the pandemic and lockdown. Cities with higher share of secondary industry, higher traffic intensity, lower population density, lower internet access, and lower fiscal capacity suffered more. However, these cities seem to have recovered well from the recession and quickly closed the economic gap in the aftermath of the pandemic and city lockdown. Our findings have broader implications for the global interventions in pandemic containment.

Pre-conceptional and prenatal exposure to secondhand smoke and autism spectrum disorder: a national multi-center study in China.

BACKGROUND: Despite extensive research evaluating the association between prenatal exposure to secondhand smoke (SHS) and the development of autism spectrum disorders (ASD), no study has investigated the association by considering the pre-conceptional period. This study aimed to investigate the associations of pre-conceptional and prenatal SHS exposure and the development of ASD among toddlers. METHODS: In this cross-sectional study, parents of 6049 toddlers aged 16-30 months were recruited from 7 tertiary hospitals, 21 communities, and 7 kindergartens located in seven cities in six provinces from five geographical regions of China. We analyzed the associations of SHS exposure and the odds of ASD among toddlers in different exposure windows (pre-conceptional and/or prenatal periods). Data were analyzed from November 2021 to January 2022. RESULTS: Among the 6049 toddlers included in the analysis [22.7 (4.1) months; 44.8% girls], 71 were identified and diagnosed with ASD. Compared with the unexposed toddlers, toddlers with pre-conceptional SHS exposure had higher odds of ASD (OR 2.30, 95% CI 1.36-3.84), while we observed a non-significantly positive association regarding prenatal SHS exposure. When considering both pre-conceptional and prenatal periods, toddlers who were continuously exposed to SHS during these two periods had higher odds than those without SHS exposure (OR 2.32, 95% CI 1.24-4.14). CONCLUSION: We reported positive SHS-ASD associations when exposed during the pre-conceptional period and continuously exposed during pre-conceptional and prenatal periods, emphasizing the critical window of pre-conception for targeted intervention on smoking.

Correlation between early life exposure to PM 2.5 and risk of autism spectrum disorder among school aged children / 中国学校卫生

Objective@#To investigate the associations between early life exposure to particulate matter with an aerodynamic diameter less than 2.5 μm (PM 2.5 ) and the risk of autism spectrum disorder (ASD) among school aged children.@*Methods@#A total of 165 children with ASD and 165 age and gender matched typical development (TD) children were recruited. Children s basic information were obtained via questionnaires, and the severity of ASD symptoms was assessed with Social Responsiveness Scale (SRS). Early life PM 2.5 exposure (preconception, entire pregnancy, and the first two years after birth) were extracted from the Tracking Air Pollution in China (TAP) datasets. Conditional Logistic regression and generalized linear model were used to evaluate the associations of early life exposure to PM 2.5 with the risk and the ASD severity symptoms, respectively.@*Results@#The PM 2.5 exposure of ASD group during preconception[(55.08±9.34)μg/m 3], entire pregnancy[(50.44±8.71)μg/m 3], the first year after birth [(45.04± 8.25 )μg/m 3] and the second year after birth [(40.19±7.12)μg/m 3] were significant higher than those in TD children [(47.66± 7.63 , 44.19±7.16, 38.95±6.07, 35.76±5.65)μg/m 3]( t =7.94, 7.13, 7.70, 6.32, P <0.05). After adjusting for potential confounding, each increase of 1 μg/m 3 in PM 2.5 was associated with higher risk of ASD during preconception ( OR=1.21, 95%CI =1.13-1.29), entire pregnancy( OR=1.18, 95%CI =1.11-1.26), the first year after birth ( OR=1.30, 95%CI =1.18-1.43) and the second year after birth ( OR=1.29, 95%CI =1.17-1.42). No similar results were observed regarding the analyses of SRS total and sub scale scores( P >0.05).@*Conclusion@#Early life exposure to PM 2.5 is relate to the risk of ASD, these findings indicated that more attention should be paid to ambient PM pollution in the early life prevention and control of ASD.

Association between parenting style and sleep problems among school aged children with autism spectrum disorder / 中国学校卫生

Objective@#To investigate the association between parenting style and sleep problems among school aged children with autism spectrum disorder (ASD).@*Methods@#A total of 98 children with ASD aged 6-10 years old and 98 age and gender matched typically developing (TD) children from mainstream schools were recruited. Parenting style and sleep problems were measured via Parent Behavior Inventory (PBI) and Children s Sleep Habits Questionnaire(CSHQ), respectively. The symptom severity and intelligence level were also evaluated. Generalized linear model was used to analyze the relationship between parenting style and sleep problems.@*Results@#There was no statistically significant difference in the parenting style of the two groups of children( P > 0.05 ); weekend sleep time of children with ASD was significantly shorter than that of the TD group [(9.1±0.7)(9.5±0.8)h, P < 0.01 ], and the score of sleep onset delay was significantly higher than that of the TD group[(1.8±0.7)(1.5±0.7), P <0.01]. However, there was no statistically significant difference in the incidence of total sleep problems and various problems between the two groups of children( P >0.05). The parental support/engagement of children with ASD was negatively associated with the total score of sleep problems( β=-2.68, 95%CI =-4.88--0.47), bedtime resistance ( β=-1.65, 95%CI =-2.54--0.77) and sleep anxiety( β=-1.01, 95%CI =-1.70--0.32). The parental hostility/coercion was positively correlated with score of daytime sleepiness( β=1.41, 95%CI =0.53-2.29)( P <0.05).@*Conclusion@#Parenting style of support/engagement is associated with lower sleep problems in children with ASD, while hostile/coercion is associated with higher sleep problems. It should be improve parental style to reduce the sleep problems in children with ASD.

Associations of emotional/behavioral problems with accelerometer-measured sedentary behavior, physical activity and step counts in children with autism spectrum disorder.

Background: The evidence for associations of emotional/behavioral status with sedentary behavior (SB), physical activity (PA) and step counts is scarce in children with autism spectrum disorder (ASD). Also, ASD-related deficiencies may affect actual levels of PA. We aimed to describe accelerometer-measured SB, PA and step counts in children with ASD, and to examine the associations of emotional/behavioral problems with SB, PA and step counts after assessing associations between accelerometer-measured SB, PA and step counts and ASD-related deficiencies. Methods: A total of 93 ASD children, aged 6-9 years, were recruited from the Center for Child and Adolescent Psychology and Behavioral Development of Sun Yat-sen University in Guangzhou, China. Participants wore an accelerometer for seven consecutive days. Of the original 93, 78 participants' accelerometer-measured valid PA were obtained, and the data were shown as time spent in SB, light, moderate, moderate-to-vigorous and vigorous PA, and step counts. Participants' emotional/behavioral problems were assessed via the Strengths and Difficulties Questionnaire (SDQ), and anxiety symptoms were evaluated by the Screen for Child Anxiety Related Emotional Disorders (SCARED). ASD-associated deficiencies include restricted repetitive behaviors (Repetitive Behavior Scale-Revised), poor social competence (Social Responsiveness Scale Second Edition) and motor development restrictions (Developmental Coordination Disorder Questionnaire). Results: Of the 78 participants, daily vigorous PA (VPA) and moderate-to-vigorous PA (MVPA) averaged 15.62 and 51.95 min, respectively. After adjustment for covariates, SDQ emotional symptoms (ß = -0.060, p = 0.028) were inversely associated with the average daily minutes in VPA. Meanwhile, SDQ emotional symptoms (ß = -0.033, p = 0.016) were inversely associated with the average daily MVPA minutes in the crude model. After adjustment for covariates, SCARED somatic/panic (ß = -0.007, p = 0.040) and generalized anxiety (ß = -0.025, p = 0.014) were negatively associated with the average daily VPA minutes; SCARED total anxiety (ß = -0.006, p = 0.029) was conversely associated with daily MVPA duration. After adjustment for covariates, no significant associations between accelerometer-measured SB, PA and step counts and ASD-related deficiencies were found (p > 0.05). Conclusions: Accelerometer-measured SB, PA and step counts showed no associations with ASD-related deficiencies. On this basis, we further found that the emotional symptoms were inversely associated with VPA and MVPA. These results emphasize the importance of VPA and MVPA in children with ASD. The longitudinally investigations on the directionality of these associations between emotional symptoms with VPA and MVPA are needed in the future.

Association of sugar-sweetened beverages with executive function in autistic children.

The association between sugar-sweetened beverages (SSBs) consumption and executive function (EF) among typically developing (TD) children has been investigated in previous studies but with inconsistent results. Furthermore, this relationship has been less investigated among autistic children who perform worse in EF compared with TD children. In this study, we aimed to investigate the association between SSB consumption and EF in autistic children, and whether the association between SSB and EF in autistic children is different from that in TD children. We recruited 106 autistic children and 207 TD children aged 6-12 years in Guangzhou, China. Children's EF was assessed by using the Chinese version of parent-reported Behavior Rating Inventory of Executive Function, Stroop Color-Word Test, and working memory subscales of the Chinese version of Wechsler Intelligence Scale for children, Fourth edition. Meanwhile, we assessed children's dietary intake and SSB consumption with a validated Food Frequency Questionnaire. In this study, 70 (66.0%) autistic children consumed SSB and 20 (18.9%) of them consumed more than two servings SSB a week. Among autistic children, over two servings per week SSB consumption was associated with poorer performance in emotional control [ß = 7.20, 95% confidence interval (CI): 0.94-13.46] and plan/Organize (ß = 6.45, 95% CI: 0.27-12.63). The association between over two servings/week SSB consumption and emotional control among autistic children was significantly different from that among TD children (ß ASD = 7.20; ß TD = -3.09, Z = 2.72, p = 0.006). Results of this study show that SSB consumption was associated with an impairment in some subscales of EF in autistic children. Furthermore, the association between SSB and EF in autistic children might be different from that in TD children.

Association between dietary quality and executive functions in school-aged children with autism spectrum disorder.

Background: It is well known that children with autism spectrum disorder (ASD) had executive functions deficit. However, it is still unclear whether the poor dietary quality is related to the impairment of executive functions. The current study aimed to explore the association between dietary quality and executive functions in children with ASD. Methods: A total of 106 children with ASD (7.7 ± 1.3 years) and 207 typically developing (TD) children (7.8 ± 1.3 years) were enrolled from Guangzhou, China. The Chinese version of Behavior Rating Scale of Executive function (BRIEF), the working memory subscales of the Chinese version of Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV), and the Stroop Color-Word Test (SCWT) were used to measure the participant's executive functions. The food frequency questionnaire (FFQ) was used to collect the dietary intake information, and the Chinese Diet Balance Index (DBI_16) was used to evaluate the dietary quality. Generalized linear models were used to estimate the association between dietary quality and executive functions. Results: In children with ASD, Low Bound Score (LBS) was positively correlated with the working memory subscale score of BRIEF (ß = 0.23, 95% CI: 0.02-0.44, P < 0.05), while High Bound Score (HBS) and LBS were positively correlated with the organizable subscale score of BRIEF (ß = 0.44, 95% CI: 0.11-0.77, P < 0.01; ß = 0.19, 95% CI: 0.01-0.37, P < 0.05). Compared to TD children, children with ASD had a higher proportion of moderate and high levels of insufficient dietary intake (moderate level, 37.7% vs. 23.2%, high level, 4.7% vs. 1.4%) and moderate level of unbalanced dietary intake (36.8% vs.21.3%), higher scores on all subscales of BRIEF (P < 0.01), and lower score on the working memory (81.3 ± 32.3 vs. 104.6 ± 12.5, P < 0.01), while there was no difference on the SCWT. Conclusion: Poor dietary quality was associated with the impairment of working memory and organizational capacity in children with ASD. This study emphasized the importance of dietary quality in executive functions among children with ASD, and attention should be paid to improving their dietary quality.

Empathizing, systemizing, empathizing-systemizing difference and their association with autistic traits in children with autism spectrum disorder, with and without intellectual disability.

Empathizing, systemizing, and empathizing-systemizing difference can be linked to autistic traits in the general adult population and those with autism spectrum disorder (ASD), but these profiles and associations remain unclear in children with ASD, with and without intellectual disability (ASD + ID; ASD-noID). We recruited three groups including 160 boys with ASD (73 ASD + ID; 87 ASD-noID) and 99 typically developing (TD) boys (6-12 years). We measured empathizing, systemizing, and empathizing-systemizing difference using the parent-reported child Empathy and Systemizing Quotient (EQ-C/SQ-C). We measured autistic traits using the Social Responsiveness Scale (SRS). Among the three groups, children with ASD + ID and ASD-noID scored lower on the EQ-C and SQ-C than TD children (all p < 0.001). There was no difference in the EQ-C between children with ASD + ID and ASD-noID (16.59 ± 5.53 vs. 16.23 ± 5.85, p = 0.973), and the difference in the SQ-C attenuated to null when adjusting for intelligence between children with ASD-noID and TD children (18.89 ± 7.80 vs. 24.15 ± 6.73, p = 0.089). Children with ASD + ID scored higher on empathizing-systemizing difference than TD children but lower than children with ASD-noID (all p < 0.05). Negative associations between EQ-C and all autistic traits, null associations between SQ-C and all autistic traits, and positive associations between empathizing-systemizing difference and all autistic traits were found in all groups. We observed differences in empathizing, systemizing, and empathizing-systemizing difference and the consistency of their associations with autistic traits among the three groups. Our findings provide implication that behavioral interventions of ASD should consider the balance of empathizing and systemizing. LAY SUMMARY: We examined the profiles of empathizing, systemizing, and empathizing-systemizing difference in children with autism spectrum disorder, with and without intellectual disability (ASD + ID; ASD-noID), and typically developing (TD) children aged 6-12 years. We observed differences in these profiles and the consistency of their associations with autistic traits among the three groups. Empathizing and empathizing-systemizing difference, rather than systemizing, were associated with autistic traits within the three groups. Our findings provide implication that behavioral interventions of ASD should consider these imbalance profiles.

The validity and reliability of the simplified Chinese version of the Social Communication Questionnaire.

This study aims to validate the simplified Chinese version of the Social Communication Questionnaire (SCQ) in children aged 2-12 years from both general and clinical populations. We recruited 819 Chinese children in this study, including 505 typically developing (TD) children, 202 children with autism spectrum disorder (ASD) and 112 children with non-ASD neurodevelopmental disorders. All the children's parents completed the simplified Chinese version of the SCQ and all children with ASD were additionally assessed for intelligence and the Childhood Autism Rating Scale to confirm their diagnosis. We have developed a 40-item, 4-factor structure of SCQ with two domains (social communication and social interaction; and restricted, repetitive, and stereotyped patterns of behavior), which showed adequate goodness of fit (comparative fit index [CFI] = 0.96, Tucker-Lewis index [TLI] = 0.95, standardized root mean squared residual [SRMR] = 0.07, root mean square error of approximation [RMSEA] = 0.05), with good internal consistency (Cronbach's alpha = 0.92). We have provided different cut-offs to distinguish ASD cases from TD children (11 for children under 4 years [sensitivity: 0.96, specificity: 0.95], 12 for children 4 years and above [sensitivity: 0.93, specificity: 0.98]) or children with other neurodevelopmental disorders (14 [sensitivity: 0.85, specificity: 0.88]). Through this large sample validation, we confirmed that the simplified Chinese version of the SCQ could be used for children aged 2-12 years with relatively good psychometric properties. LAY SUMMARY: We aimed to develop the simplified Chinese version of the Social Communication Questionnaire (SCQ) for Chinese children aged 2-12 years as a screening tool to identified potential risk of autism spectrum disorder (ASD). We have developed a 40-item, 4-factor structure of SCQ with two domains, which showed adequate goodness of fit and good psychometric properties. We also provided different cut-offs to identify ASD cases in general or clinical populations.

The epidemiological evidence linking exposure to ambient particulate matter with neurodevelopmental disorders: A systematic review and meta-analysis.

BACKGROUND: There has been increasing attention on the associations between ambient particulate matter (PM) in early-life and neurodevelopmental disorders (NDDs). However, the associations remained unclear when considering different types of NDDs and different sizes of PM, and vulnerable exposure windows during early-life were not identified yet. OBJECTIVE: To synthesize the published literature on the associations between ambient particulate matter (PM) and risk of different types of neurodevelopmental disorders (NDDs) in a systematic review and meta-analysis. METHODS: A systematic search of Medline, Embase, PubMed, Cochrane Library, and Web of Science was performed from inception through 24 January 2022. Two reviewers conducted the study selection, data extraction, and quality appraisal. A random-effects model was used for meta-analyses with two quality-of-evidence assessments (the Grading of Recommendations Assessment, Development, and Evaluation system and the best evidence synthesis system). RESULTS: A total of 6554 articles were screened, of which 31 were included in the review, and 20 provided adequate data for meta-analyses. Exposures to particulate matter of 2.5 µm or less (PM2.5) during prenatal periods (OR, 1.32 [95%CI, 1.03-1.69]), the first year after birth (OR, 1.62 [95%CI, 1.22-2.15]) and the second year after birth (OR, 3.13 [95%CI, 1.47-6.67]) were associated with increased risk of autism spectrum disorders (ASD) in children. The quality of evidence for these associations during early postnatal periods was somewhat moderate with limited studies. We found inconsistent evidence when considering other types of NDDs and different sizes of PM. CONCLUSIONS AND RELEVANCE: Current evidence indicated that there might be an association between PM2.5 exposure and higher risk of ASD, and early postnatal periods appeared to be the critical exposure window. High-quality studies are needed to assess the evidence for other types of NDDs.

Enhancing Lithium-Storage Performance via Graphdiyne/Graphene Interface by Self-Supporting Framework Synthesized.

The self-supporting graphdiyne/exfoliated graphene (GDY/EG) composites materials were prepared by the solvothermal method and applied as lithium-ion batteries (LIBs). Graphdiyne (GDY) is a new type of carbon allotrope with a natural macroporous structure, but its conductivity is poor. A small amount of highly conductive graphene can improve surface conductivity and facilitate electron transport. The layered GDY/graphene heterogeneous interface can reduce the electron aggregation polarization, enhance the ability to obtain electrons from the electrolyte, and form a more uniform solid-electrolyte interface (SEI) film. The structural performance and electrochemical performance have been systematically studied. The results showed that the GDY/EG composite electrode has a reversible capacity of 1253 mA h g-1 after 600 cycles at a current density of 0.5 A g-1. When the current density is 5 A g-1, the GDY/EG composite electrode can still maintain a reversible capacity of 324 mA h g-1 after 2000 cycles, and the electrode can still maintain a good morphology after recycling. GDY/EG has a high reversible capacity, excellent rate capability, and cycle stability. A small amount of EG and inner foam copper form a double-layer conductivity, which changes the storage method of lithium ions and facilitates the rapid diffusion of lithium ions.

Applying strong external electric field to thiophene-based oligomers: A promising approach to upgrade semiconducting performance.

A key parameter dictating the rate of charge transfer (CT) is reorganization energy (λ), an energy associated with geometry changes during hole/electron transfer. We show that "ironing" the inter-ring dihedral angles of oligothiophenes via proper substitutions or insertions (e.g., -OR, -F or -C≡C-), decreases the λ and thus promotes CT according to Marcus equation. Our results demonstrate, to attain a smaller λ, extending oligomer length is only significant if the flattened backbone structure is realized. Of great interest is that external electric fields, which are ubiquitous in electronic devices yet commonly overlooked in the computation of λ, can have a significantly greater impact than conventional substitutions. It is important to emphasize, the responses of λ to external fields is system-dependent. Compared to fused-ring conjugated systems, single-bond connected thiophenes are more sensitive to external fields. Fx lowers the λ (552 meV) of quaterthiophene by almost 80% at the intensity of 1 V/Å, down to a value (125 meV) which is even lower than that of pentacene (154 meV) and rubrene (219 meV) at the same level of theory. © 2016 Wiley Periodicals, Inc.

[Protective effects of three phenylallyl compounds from Guizhi decoction ox-LDL-induced oxidative stress injury of human brain microvascular endothelial cells].

The main objective of this research is to observe protective effects of three phenylallyl compounds(cinnamyl alcohol,cinnamaldehyde and cinnamic acid)from Guizhi decoction against ox-LDL-induced oxidative stress injury on human brain microvascular endothelial cells(HBMEC).In this study,the toxicity and optimal protective concentration of three phenylallyl compounds from Guizhi decoction were determined by MTT assay.The HBMEC were divided into control group(DMSO),model group(ox-LDL),tert-butylhydroquinone (t-BHQ) group,cinnamyl alcohol group, cinnamaldehyde group and cinnamic acid group.The model group were treated with ox-LDL (50 mg•L⁻¹)for 24 h,other groups were separately treated with t-BHQ, cinnamyl alcohol, cinnamaldehyde and cinnamic acid of 20 µmol•L⁻¹, and exposed to ox-LDL (50 mg•L⁻¹) for 24 h at the same time.The survival rate of HBMEC was detected by MTT assay,reactive oxygen species(ROS) production of injured cells were detected using laser scanning confocal microscope (LSCM),the content of SOD, MDA, eNOS and NO in HBMEC was determined by ELISA, and the expressions of Nrf2 mRNA were detected by quantitative Real-time PCR(qRT-PCR).The results shows that oxidative stress injury of HBMEC could be induced by ox-LDL, the three phenylallyl compounds from Guizhi decoction did not affect morphology and viability of normal HBMEC.Compared with model group, the three phenylallyl compounds from Guizhi decoction could improve the above oxidative stress status and up-regulate Nrf2 mRNA expressions in injured HBMEC(P<0.05, P<0.01) .These findings suggested that the three phenylallyl compounds from Guizhi decoction have certain protective effects against ox-LDL-induced oxidative stress injury on HBMEC(cinnamaldehyde> t-BHQ> cinnamic acid>cinnamyl alcohol),the protective mechanism maybe related to regulation of antioxidant enzymes gene expression in HBMEC by Nrf2.