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Contrasting effects of sulfidation on contaminants reduction by zero-valent iron (ZVI) has been reported in literature but the underlying mechanisms remain unclear. Here, under well-controlled conditions, we compared the performance of ZVI and sulfidated ZVI (S-ZVI) toward a series of chlorinated compounds. Results revealed that, although S-ZVI was more reactive than ZVI toward hexachloroethane, pentachloroethane, tetrachloroethylene, and trichloroethene, sulfidation hindered the dechlorination of the other ten tested chlorinated aliphatics by a factor of 1.5-125. Moreover, S-ZVI may lead to an accumulation of toxic partially-dechlorinated products. Analogous to its effects on ZVI reactivity, sulfidation also exerted positive, negligible, or negative effects on the electron efficiency of ZVI. Solvent kinetic isotope effect analysis suggested that direct electron transfer rather than reaction with atomic hydrogen was the dominant reduction mechanism in S-ZVI system. Hence, the sulfidation enhancing effects could be expected only when direct electron transfer is the preferred reduction route for target contaminants. Furthermore, linear free energy relationships analysis indicated one-electron reduction potential could be used to predict the transformation of chlorinated ethanes by S-ZVI, whereas for chlorinated ethenes, their adsorption properties on S-ZVI determined the dechlorination process. All these findings may offer guidance for the decision-making regarding the application of S-ZVI.
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Listeria monocytogenes biofilms represent a continuous source of contamination, leading to serious food safety concerns and economic losses. This study aims to develop novel nisin-loaded chitosan nanoparticles (CSNPs) functionalized with DNase I and evaluate its antibiofilm activity against L. monocytogenes on food contact surfaces. Nisin-loaded CSNPs (CS-N) were first prepared by ionic cross-linking, and DNase I was covalently grafted on the surface (DNase-CS-N). The NPs were subsequently characterized by Zetasizer Nano, transmission electron microscopy, Fourier transform infrared (FT-IR), and X-ray diffraction (XRD). The antibiofilm activity of NPs was evaluated against L. monocytogenes on polyurethane (PU). The DNase-CS-N was fabricated and characterized with quality attributes (particle size-427.0 ± 15.1 nm, polydispersity [PDI]-0.114 ± 0.034, zeta potential-+52.5 ± 0.2 mV, encapsulation efficiency-46.5% ± 3.6%, DNase conjugate rate-70.4% ± 0.2). FT-IR and XRD verified the loading of nisin and binding of DNase I with chitosan. The DNase-CS-N caused a 3 log colony-forming unit (CFU)/cm2 reduction of L. monocytogenes biofilm cells, significantly higher than those in CSNPs (1.4 log), CS-N (1.8 log), and CS-N in combination with DNase I (2.2 log) treatment groups. In conclusion, nisin-loaded CSNPs functionalized with DNase I were successfully prepared and characterized with smooth surface and nearly spherical shape, high surface positive charge, and good stability, which is effective to eradicate L. monocytogenes biofilm cells on food contact surfaces, exhibiting great potential as antibiofilm agents in food industry. PRACTICAL APPLICATION: Listeria monocytogenes biofilms are a common safety hazard in food processing. In this study, novel nanoparticles were successfully constructed and are expected to be a promising antibiofilm agent in the food industry.
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Quitosana , Listeria monocytogenes , Nanopartículas , Nisina , Nisina/farmacologia , Quitosana/farmacologia , Quitosana/química , Desoxirribonuclease I , Espectroscopia de Infravermelho com Transformada de Fourier , Biofilmes , Nanopartículas/químicaRESUMO
CLINICAL RELEVANCE: Online family health education may be effective for myopia prevention in children, and the effects may be different between children with myopic and non-myopic parents. BACKGROUND: Myopia is a common cause of vision loss. The aims of this study were to evaluate the effects of online family health education on preventing the development of myopia in children, and to estimate whether the effects vary according to parental myopia. METHODS: A cluster randomised trial including grade 1 and grade 2 children from 12 primary schools was conducted in Guangzhou, China. Weekly online family health education messages were sent to parents in the intervention group. Data collection included eye examinations of children and questionnaires completed by parents. RESULTS: Among the 3123 children included at baseline (1703 boys [54.5%]; mean [SD] age, 6.83 [0.73] years), 2376 completed the follow-up after 3 years. The differences in the incidence of myopia and myopic shift between the study groups were not significant in total. However, the 3-year cumulative incidence rate of myopia in the intervention group (125 of 445 [28.1%]) was significantly lower than that in the control group (225 of 603 [37.3%]; difference, 9.2% [95% CI, -14.9% to -3.5%]; P = 0.001) among children with non-myopic parents. In parallel, among children with non-myopic parents, the mean myopic change in SER was less for the intervention group than for the control group (-1.10 D vs. -1.24 D; difference, 0.13 D [95% CI, 0.03 to 0.23 D]; P = 0.01). CONCLUSIONS: Compared with children with myopic parents, online family health education was more effective in children with non-myopic parents. The incidence of myopia and myopic shift in refraction have been reduced in children with non-myopic parents. Further studies are needed to assess these differences by parental myopia.
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Miopia , Masculino , Criança , Humanos , Progressão da Doença , Miopia/epidemiologia , Miopia/prevenção & controle , Pais , Refração Ocular , Educação em SaúdeRESUMO
BACKGROUND: The development trajectories of children's SER remain unknown. This study aimed to characterize spherical equivalent refraction (SER) trajectories during grades 1-4 in Chinese children. METHODS: This prospective cohort study included 1226 first-grade non-myopic children from 12 public primary schools, randomly selected in two districts in Guangzhou, China. From November 2018 to March 2022, four-wave ocular examinations and questionnaire surveys have been completed. The group-based trajectory modeling was used to explore SER trajectories in grades 1-4. RESULTS: All five trajectories showed an upward trend and rose faster after grade 2. Children in the sharp-developing (n = 44), high-developing (n = 136), and rapid-developing (n = 237) myopia groups developed myopia before grades 2, 3, and 4, respectively. Their SER development speed remained at a relatively high level after myopia, almost consistent with that before myopia. Children in the moderate-developing (n = 418) and low-developing (n = 391) non-myopia groups did not develop myopia before grade 4. Some characteristics in grade 1 were independently associated with SER trajectories, including sex, axial length, number of parents with myopia, residence, academic achievement, and the duration of outdoor activity. Based on the baseline characteristics, we established the model predicting the probability of children belonging to each group. CONCLUSIONS: Myopia interventions are best started in grade 1 or preschool age. If interventions are not taken in time, the latest intervention window might be in grades 1, 2, and 3 for children with a high probability of belonging to the sharp-developing, high-developing, and rapid-developing myopia groups, respectively. The above probabilities might be predicted using the model we established. Moreover, the interventions for myopic children shouldn't be ignored.
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Miopia , Refração Ocular , Criança , Humanos , Estudos Prospectivos , Testes Visuais , Miopia/epidemiologia , China/epidemiologiaRESUMO
Salmonella is one of the pathogens that cause many foodborne outbreaks throughout the world, representing an important global public health problem. Salmonella strains with biofilm-forming abilities have been frequently isolated from different food processing plants, especially in poultry industry. Biofilm formation of Salmonella on various surfaces can increase their viability, contributing to their persistence in food processing environments and cross-contamination of food products. In recent years, increasing concerns arise about the antimicrobial resistant and disinfectant tolerant Salmonella, while adaptation of Salmonella in biofilms to disinfectants exacerbate this problem. Facing difficulties to inhibit or remove Salmonella biofilms in food industry, eco-friendly and effective strategies based on chemical, biotechnological and physical methods are in urgent need. This review discusses biofilm formation of Salmonella in food industries, with emphasis on the current available knowledge related to antimicrobial resistance, together with an overview of promising antibiofilm strategies for controlling Salmonella in food production environments.
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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.
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Ansiedade , População do Leste Asiático , Receptores de Glucocorticoides , Adolescente , Criança , Humanos , Masculino , Ansiedade/genética , Estudos de Casos e Controles , Metilação de DNA , Hidrocortisona , Estudos Longitudinais , Receptores de Glucocorticoides/genética , FemininoRESUMO
Purpose: To distinguish the effects of age and grade on the development of myopia. Methods: Grade 1 (n = 1465, mean age 6.71 ± 0.29 years; 53.5% male) and Grade 2 students (n = 1381, mean age 7.76 ± 0.30 years; 52.5% male) were examined in 2018, with a follow-up examination in 2019. Cycloplegic spherical equivalent (SE) in diopter (D) was measured. Regression discontinuity (RD) analysis was used to assess the causal effects on refraction at each visit. Results: The sample in a grade was divided into three 4-month age blocks according to their birth month, the youngest, middle, and the oldest. At the 2018 visit, within each grade, there were no significant differences in SE among age blocks (all P > 0.05), despite an age range of 12 months. However, comparing the youngest block in Grade 2 to the oldest block in Grade 1, an average age difference of four months, a significant difference in SE was found (0.82 ± 0.69 D vs. 1.05 ± 0.55 D, t-test P < 0.01). Formal RD analysis found a significant casual effect of grade increase on myopic refraction shift (ß = -0.32 D; 95% CI, -0.73 to -0.01; P = 0.042). Consistent results were found using the 2019 data. Conclusions: Increased grade, rather than increasing age, is the major cause of myopic shifts in refraction. A causal link implies that interventions aimed at reducing the myopigenic exposures experienced during a school year have the potential to markedly reduce the myopic shifts in refraction associated with a grade of schooling.
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Miopia , Humanos , Masculino , Lactente , Criança , Feminino , Miopia/etiologia , Refração Ocular , Testes Visuais , Escolaridade , Causalidade , Progressão da DoençaRESUMO
BACKGROUND: Environmental pollution may give rise to the incidence and progression of nonalcoholic fatty liver disease (NAFLD), the most common cause for chronic severe liver lesions. Although knowledge of NAFLD pathogenesis is particularly important for the development of effective prevention, the relationship between NAFLD occurrence and exposure to emerging pollutants, such as microplastics (MPs) and antibiotic residues, awaits assessment. OBJECTIVES: This study aimed to evaluate the toxicity of MPs and antibiotic residues related to NAFLD occurrence using the zebrafish model species. METHODS: Taking common polystyrene MPs and oxytetracycline (OTC) as representatives, typical NAFLD symptoms, including lipid accumulation, liver inflammation, and hepatic oxidative stress, were screened after 28-d exposure to environmentally realistic concentrations of MPs (0.69mg/L) and antibiotic residue (3.00µg/L). The impacts of MPs and OTC on gut health, the gut-liver axis, and hepatic lipid metabolism were also investigated to reveal potential affecting mechanisms underpinning the NAFLD symptoms observed. RESULTS: Compared with the control fish, zebrafish exposed to MPs and OTC exhibited significantly higher levels of lipid accumulation, triglycerides, and cholesterol contents, as well as inflammation, in conjunction with oxidative stress in their livers. In addition, a markedly smaller proportion of Proteobacteria and higher ratios of Firmicutes/Bacteroidetes were detected by microbiome analysis of gut contents in treated samples. After the exposures, the zebrafish also experienced intestinal oxidative injury and yielded significantly fewer numbers of goblet cells. Markedly higher levels of the intestinal bacteria-sourced endotoxin lipopolysaccharide (LPS) were also detected in serum. Animals treated with MPs and OTC exhibited higher expression levels of LPS binding receptor (LBP) and downstream inflammation-related genes while also exhibiting lower activity and gene expression of lipase. Furthermore, MP-OTC coexposure generally exerted more severe effects compared with single MP or OTC exposure. DISCUSSION: Our results suggested that exposure to MPs and OTC may disrupt the gut-liver axis and be associated with NAFLD occurrence. https://doi.org/10.1289/EHP11600.
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Hepatopatia Gordurosa não Alcoólica , Oxitetraciclina , Animais , Oxitetraciclina/toxicidade , Oxitetraciclina/metabolismo , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/microbiologia , Poliestirenos/toxicidade , Peixe-Zebra/genética , Microplásticos/toxicidade , Plásticos/metabolismo , Lipopolissacarídeos/metabolismo , Antibacterianos/toxicidade , Fígado/metabolismo , Inflamação/induzido quimicamenteRESUMO
Human papillomavirus (HPV) persistence is the most critical cause of cervical cancer. This study focuses on exploring the prevalence and risk factors related to persistent HPV infection among rural Chinese women. Participants were recruited through a multi-stage stratified cluster sample. A total of 847 women were initially selected in 2015, and 159 were detected HPV-DNA positive at baseline. A two-year follow-up was conducted for those who were HPV-DNA positive at baseline. HPV infection was evaluated at both baseline and follow-up. Depending on the results of two HPV tests, women were divided into two categories: (1) persistence; (2) clearance. Student's t, chi-square and logistic regression were employed to find the risk factors for HPV persistence and the relationship between HPV persistence and cervical intraepithelial neoplasia (CIN). Among 129 participants with HPV16/18 infection at baseline, 60 (46.51 percent) were reported to have persistent HPV16/18 infection. Oral contraceptive use and menopause were the significant factors related to persistent HPV16/18 infection. The persistence of HPV infection was significantly related to CIN. Our results indicate that better HPV prevention strategies for rural Chinese women should be developed.
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Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , China/epidemiologia , Estudos de Coortes , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 18 , Humanos , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Displasia do Colo do Útero/complicações , Displasia do Colo do Útero/epidemiologiaRESUMO
Although the impacts of ocean acidification and warming on marine organisms have been increasingly documented, little is known about the affecting mechanism underpinning their interactive impacts on physiological processes such as metabolism. Therefore, the effects of these two stressors on metabolism were investigated in thick-shell mussel Mytilus coruscus in this study. In addition, because metabolism is primarily regulated by circadian rhythm and neurotransmitters, the impacts of acidification and warming on these two regulatory processes were also analyzed. The data obtained demonstrated that the metabolism of mussels (indicated by the clearance rate, oxygen consumption rate, ammonia excretion rate, O:N ratio, ATP content, activity of pyruvate kinase, and expression of metabolism-related genes) were significantly affected by acidification and warming, resulting in a shortage of energy supply (indicated by the in vivo content of ATP). In addition, exposure to acidification and warming led to evident disruption in circadian rhythm (indicated by the heartrate and the expression rhythm of Per2, Cry, and BMAL1) and neurotransmitters (indicated by the activity of acetyl cholinesterase and in vivo contents of ACh, GABA, and DA). These findings suggest that circadian rhythms and neurotransmitters might be potential routes through which acidification and warming interactively affect the metabolism of mussels.
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Mytilus , Água do Mar , Animais , Ritmo Circadiano , Concentração de Íons de Hidrogênio , Mytilus/metabolismo , Neurotransmissores/metabolismo , Oceanos e MaresRESUMO
BACKGROUND: Anxiety symptoms are common mental health problems among adolescents worldwide. This study aimed to explore (1) the longitudinal association between childhood maltreatment and anxiety symptoms, (2) the association between childhood maltreatment and DNA methylation of the FKBP5 gene, and (3) the association of DNA methylation of the FKBP5 gene with anxiety symptoms at follow-up. METHODS: A nested case-control design was conducted to identify a case group and control group from a longitudinal study of adolescents aged 13-18 years in Guangzhou from 2019 to 2020. Adolescents with anxiety symptoms at baseline and follow-up were considered the case group, while those without anxiety symptoms at baseline and follow-up were considered the control group. The case and control groups were matched according to age and sex. Our study finally included 97 cases and 141 controls. RESULTS: After adjusting for significant covariates, childhood emotional abuse was associated with subsequent anxiety symptoms (ß = 0.146, 95% CI = 0.010~0.283); students with physical and emotional neglect were more likely to get a lower level of DNA methylation at most CpG units of FKBP5 gene (P < 0.05); FKBP5-12 CpG 15 methylation was associated with anxiety symptoms at follow-up (ß = -0.263, 95% CI = -0.458~-0.069). However, after multiple hypothesis testing, childhood maltreatment was not associated with FKBP5 DNA methylation (q > 0.10); FKBP5 DNA methylation did not show an association with subsequent anxiety symptoms (q > 0.10). CONCLUSIONS: Childhood emotional abuse was associated with an increased risk of anxiety symptoms among Chinese adolescents. After multiple hypothesis testing, childhood maltreatment was not significantly associated with FKBP5 DNA methylation. DNA methylation of the promoter region of the FKBP5 gene was not a significant predictor of anxiety symptoms. More attention should be paid to the mental health of adolescents with childhood maltreatment.
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By employing external fertilization (broadcast spawning) as a mating strategy, the gametes and subsequent fertilization of various marine invertebrates are directly subjected to pollution. Although microplastics (MPs) are ubiquitous in marine environments, their potential effects on the fertilization of broadcast spawners remain largely unknown. Therefore in this study, the impacts of polystyrene MPs on the fertilization success of broadcast spawning bivalve (Tegillarca granosa) were investigated. In order to reveal the underlying mechanisms affecting fertilization, the sperm swimming performance, sperm ATP status, sperm viability, DNA integrity, gamete collision probability, gamete fusion efficiency, enzymatic antioxidants, and key ion transport enzyme activities were analyzed. The results showed that MPs weakened the sperm swimming performance through reducing ATP production and cell viability, thus leading to the decreased probability of gamete collision. Furthermore, MPs affected ion transport in the gametes by inducing oxidative stress, which resulted in gamete fusion failure. In conclusion, this study demonstrates that MPs could significantly decrease the fertilization success of T. granosa through reducing gamete collision and lowering gamete fusion efficiency.
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Bivalves , Células Germinativas/efeitos dos fármacos , Microplásticos , Poluentes Químicos da Água , Animais , Bivalves/efeitos dos fármacos , Fertilização , Masculino , Microplásticos/toxicidade , Espermatozoides , Poluentes Químicos da Água/toxicidadeRESUMO
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.
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Depressão , Poder Familiar , Adolescente , Estudos de Casos e Controles , China , Estudos de Coortes , Depressão/genética , Humanos , Metilação , Polimorfismo de Nucleotídeo Único/genética , Proteínas de Ligação a Tacrolimo/genéticaRESUMO
Importance: Myopia is a common cause of vision loss, and its prevalence is increasing globally. Objective: To evaluate the effects of school-based family health education via WeChat in raising parents' awareness of myopia prevention and behavior and in controlling the development of myopia in children. Design, Setting, and Participants: A single-masked cluster randomized clinical trial of children was conducted from October 1, 2018, to December 31, 2020, among grade 1 students from 12 primary schools in Guangzhou, China. The 12 primary schools were randomly selected in 2 districts and randomized to the intervention and control groups. All grade 1 students were invited to participate, and 688 students were included in the intervention group and 752 in the control group. Interventions: Weekly health education via the social media platform WeChat was provided to the parents in the intervention group. Main Outcomes and Measures: Data include results of eye examinations of children and questionnaires completed by parents. The primary outcome was the 2-year cumulative incidence rate of myopia. Myopia was defined as a spherical equivalent (SE) refractive error (sphere of +0.5 cylinder) of at least -0.50 diopters (D). The secondary outcomes were the 2-year changes in the axis length and SE refraction, parental awareness, children's screen time, outdoor activities, and learning tools during COVID-19. Results: Among the 1525 children included at baseline (835 boys [54.8%]; mean [SD] age, 6.3 [0.5] years), 1244 competed the final assessment; the 2-year cumulative incidence rate of myopia was 106 of 544 (19.5%) in the intervention group and 171 of 700 (24.4%) in the control group (difference, 4.9% [95% CI, 0.3%-9.5%]; P = .04). The mean myopic shift in SE refraction in the intervention group (-0.82 D) was lower than that in the control group (-0.96 D; difference, -0.14 [95% CI, -0.22 to -0.06] D; P < .001). No difference in change in axial length was detected (difference, 0.02 [95% CI, -0.06 to 0.09] mm; P = .70). Conclusions and Relevance: School-based weekly family health education via WeChat resulted in a small decrease in the 2-year cumulative incidence rate of myopia with a difference in SE of less than 0.25 D not accompanied by any axial length differences. Whether these findings extrapolate elsewhere in the world or are clinically relevant in the short or long term remain to be determined. Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR1900022236.
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Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Miopia , Pais , Mídias Sociais , Adulto , COVID-19 , Criança , China , Feminino , Humanos , Masculino , Miopia/epidemiologia , Miopia/prevenção & controle , Refração Ocular , SARS-CoV-2 , Instituições AcadêmicasRESUMO
With the fast growth of the production and application of engineered nanomaterials (ENMs), nanoparticles (NPs) that escape into the environment have drawn increasing attention due to their ecotoxicological impacts. Motile microalgae are a type of primary producer in most ecosystems; however, the impacts of NPs on the motility of microalgae have not been studied yet. So the toxic impacts of three common metal oxide NPs (nTiO2, nZnO, and nFe2O3) on swimming speed and locomotion mode of a marine microalgae, Platymonas subcordiformis, were investigated in this study. Our results demonstrated that both the velocity and linearity (LIN) of swimming were significantly decreased after the exposure of P. subcordiformis to the tested NPs. In addition, the obtained data indicate that NPs may suppress the motility of P. subcordiformis by constraining the energy available for swimming, as indicated by the significantly lower amounts of intracellular ATP and photosynthetic pigments and the lower activities of enzymes catalyzing glycolysis. Incubation of P. subcordiformis with the tested NPs generally resulted in the overproduction of reactive oxygen species (ROS), aggravation of lipid peroxidation, and induction of antioxidant enzyme activities, suggesting that imposing oxidative stress, which may impair the structural basis for swimming (i.e. the membrane of flagella), could be another reason for the observed motility suppression. Moreover, NP exposure led to significant reductions in the cell viability of P. subcordiformis, which may be due to the disruption of the energy supply (i.e., photosynthesis) and ROS-induced cellular damage. Our results indicate that waterborne NPs may pose a great threat to motile microalgae and subsequently to the health and stability of the marine ecosystem.
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Nanopartículas Metálicas , Microalgas , Nanopartículas , Poluentes Químicos da Água , Ecossistema , Nanopartículas Metálicas/toxicidade , Óxidos , Poluentes Químicos da Água/toxicidadeRESUMO
Inflammatory bowel disease (IBD) is a refractory disorder characterized by chronic and recurrent inflammation. The progression and pathogenesis of IBD is closely related to oxidative stress and irregularly high concentrations of reactive oxygen species (ROS). A new oxidation-responsive nano prodrug was constructed from a phenylboronic esters-modified carboxylmethyl chitosan (OC-B) conjugated with berberine (BBR) that degrades selectively in response to ROS. The optimized micelles exhibited well-controlled physiochemical properties and stability in a physiological environment. OC-B-BBR micelles could effectively encapsulate the anti-inflammatory drug berberine and exhibit ideal H2O2-triggered release behavior as confirmed by in vitro drug loading and release studies. The in vivo anti-inflammatory effect and regulation of gut microbiota caused by it were explored in mice with colitis induced by dextran sodium sulfate (DSS). The results showed that OC-B-BBR significantly ameliorated colitis symptoms and colon damage by regulating the expression levels of IL-6 and remodeling gut microbiota. In summary, this study exhibited a novel BBR-loaded Carboxylmethyl Chitosan nano delivery system which may represent a promising approach for improving IBD treatment.
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OBJECTIVE: Few studies are conducted to explore the longitudinal relationships between sleep situations and mental health among adolecents. This study aimed to explore the sleep situations (ie, sleep habits and sleep problems) among Chinese adolescents and the longitudinal associations between sleep situations and mental disorder symptoms (ie, depressive and anxiety symptoms). METHODS: This longitudinal study included 1957 high school students from ten schools in Guangzhou in January 2019, with 1836 students contributing valid data at a one-year follow-up (retention rate: 93.9%). Data of depressive and anxiety symptoms, sleep habits, and sleep problems were collected using a self-reported questionnaire. RESULTS: The current study found that over half of the adolescents did not reach the recommended 8-h sleep-time on weekdays (63.3%). Short sleep duration, especially on weekdays, was significantly associated with subsequent depressive (AOR = 0.86, 95%CI: 0.80-0.92) and anxiety symptoms (AOR = 0.86, 95%CI: 0.77-0.96). In addition, longer weekday-weekend catch-up sleep and more sleep problems were risk factors of depressive and anxiety symptoms. CONCLUSIONS: The health effects of insufficient sleep and suboptimal sleep quality on adolescents should not be neglected. Our longitudinal research showed that adolescents would demonstrate severer depressive and anxiety symptoms if lacking of a healthy sleeping practice. A regular sleep schedule and close attention to adolescents' mental disorders are highly recommended.
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Depressão , Saúde Mental , Adolescente , China/epidemiologia , Depressão/epidemiologia , Humanos , Estudos Longitudinais , Sono , Inquéritos e QuestionáriosRESUMO
Microplastics (MPs) and polycyclic aromatic hydrocarbons (PAHs) are universally detected in the marine ecosystem and may exert adverse impacts on marine species. Although under realistic pollution scenarios, PAH pollution usually occurs as a mixture of different PAH compounds, the toxic impacts of PAH mixtures on marine organisms remain largely unknown to date, including their interactions with other emergent pollutants such as MPs. In this study, the single and combined toxic impacts of polystyrene MPs and a mixture of PAHs (standard mix of 16 representative PAHs) on haematic parameters were evaluated in the blood clam Tegillarca granosa. Our data demonstrated that blood clams treated with the pollutants examined led to decreased total haemocyte count (THC), changed haematic composition, and inhibited phagocytosis of haemocytes. Further analyses indicated that MPs and a mixture of PAHs may exert toxic impacts on haematic parameters by elevating the intracellular contents of reactive oxygen species (ROS), giving rise to lipid peroxidation (LPO) and DNA damage, reducing the viability of haemocytes, and disrupting important molecular signalling pathways (indicated by significantly altered expressions of key genes). In addition, compared to clams treated with a single type of pollutant, coexposure to MPs and a mixture of PAHs exerted more severe adverse impacts on all the parameters investigated, indicating a significant synergistic effect of MPs and PAHs.
Assuntos
Bivalves , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Ecossistema , Microplásticos , Plásticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
BACKGROUND: To investigate the independent association between different types of emotional and behavioral problems and Internet use (i.e., Internet use time and problematic Internet use [PIU]) among Chinese young adults, and to test whether these associations vary by academic performance. METHODS: Data was drawn from the 2019 National School-based Chinese Adolescents Health Survey, and 30,581 undergraduates (mean age: 19.9 [SD: 1.6] years) completed standard questionnaires qualifiedly. Daily hours of Internet use, PIU, emotional and behavioral problems, and academic performance were measured. RESULTS: After adjusting for control variables and academic performance, students who reported having emotional problems (daily hours: adjusted unstandardized ß estimate=0.14, 95% CI=0.12~0.15; PIU: adjusted unstandardized ß estimate=1.82, 95% CI=1.77~1.89), conduct problems (daily hours: adjusted unstandardized ß estimate=0.12, 95% CI=0.09~0.15; PIU: adjusted unstandardized ß estimate=1.76, 95% CI=1.67~1.84), hyperactivity (daily hours: adjusted unstandardized ß estimate=0.08, 95% CI=0.06~0.12; PIU: adjusted unstandardized ß estimate=1.46, 95% CI=1.38~1.54), and peer problems (daily hours: adjusted unstandardized ß estimate=0.03, 95% CI=0.002~0.05; PIU: adjusted unstandardized ß estimate=0.53, 95% CI=0.44~0.62) were more likely to engaged in prolonged daily Internet use and PIU. In contrast, prosocial behavior was negatively associated with Internet use time and PIU. Stratified analyses showed that some of the associations in poor academic performers were stronger than in students with good and average academic performance. LIMITATIONS: The cross-sectional design limited the ability to make causal inferences. CONCLUSIONS: The findings suggest that the efforts to prevent abnormal Internet use should be focused on students with emotional and behavioral problems or poor academic performance.
Assuntos
Desempenho Acadêmico , Comportamento do Adolescente , Comportamento Aditivo , Comportamento Problema , Adolescente , Adulto , Comportamento Aditivo/epidemiologia , China/epidemiologia , Estudos Transversais , Humanos , Internet , Uso da Internet , Adulto JovemRESUMO
BACKGROUND: Studies that focus on the relationships of problematic Internet use (PIU), sleep disorders, and behavioral/emotional problems were limited. This study aimed to explore (1) the relationship between PIU and behavioral/emotional problems among Chinese adolescents and (2) whether sleep disorders mediate the relationship between PIU and behavioral/emotional problems. METHODS: A total of 1,976 adolescents were recruited by cluster sampling from ten secondary schools in Guangzhou between January and April 2019, and 1,956 of them provided valid information (response rate: 98.9% ). Among them, 50.8% were males and the mean age was 13.6±1.5 years, ranging from 11 to 18 years. Data on behavioral/emotional problems, sleep disorders, and PIU were collected using a self-reported questionnaire. Linear regression models and mediation analyses were performed. RESULTS: Of the participants, 14.5% (284/1,956) reported moderate to severe PIU, and their average score for total difficulties was significantly higher than the score for average users (14.9±5.5 Vs 9.8±4.7). After adjusting for controlled variables, PIU was further proven to be positively related to elevated levels of behavioral/emotional problems (unstandardized ß = 0.16, p < 0.05). In addition, sleep disorders partially mediated the forgoing associations. CONCLUSIONS: Adolescents with problematic Internet habits were at higher risk of developing behavioral and emotional problems than their normal-use peers, and sleep disorders partially mediated the effect. Close attention and effective guidance for adolescents with PIU and behavioral/emotional problems were recommended for parents and schools.