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1.
Ecotoxicol Environ Saf ; 184: 109612, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31476450

RESUMO

Microplastics (MPs) are small plastic pieces with size less than 5 mm that have entered and polluted the environment. While many investigations including several critical reviews on MPs in the environment have been conducted, most of them are focused on their occurrences in marine environment. Current understanding on the occurrences, behaviors, and impacts of MPs in the terrestrial environment is far from complete. A systematic review of the literature was thus conducted to promote the research on MPs in the environment. This work is designed to provide a comprehensive overview that summarizes current knowledge and research findings on environmental occurrences, fate and transport, and impacts of MPs. In addition to discussing the occurrences, characteristics, and sources of MPs in the ocean, freshwater, sediments, soils, and atmosphere, the review also summarizes both the experimental and modeling data of the environmental fate and transport of MPs. Research findings on the toxic effects, bioaccumulation, and bioavailability of MPs in the environment are also covered in this critical review. Future perspectives are discussed as well.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31478303

RESUMO

A two-dimensional (2D) carbon nanofilm with uniform artificial nanopores is an ideal material to ultimately suppress the fuel permeation in the proton exchange membrane fuel cells. Graphdiyne has great mechanical strength, high dimensional stability, and controllable nanopores, and has good prospects to play this crucial role. It is found that graphdiyne nanofilm with amino groups and natural nanopores can be easily prepared with high integrity. The aminated graphdiyne has good compatibility with the Nafion matrix owing to the acid-base interaction between them. The excellent comprehensive properties of graphdiyne in selectivity, dimensional stability, and integrity effectively improve the power performance and stability of fuel cells at wide temperature. Our results can be developed into a universal method that can easily realize the selective separation of ions and small molecules, and open a new way for the emerging applications in green energy.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31507165

RESUMO

The exploration of robust multifunctional electrocatalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is a continuing challenge to the sustainable energy sources. However, as the key reactions in renewable metal-air batteries and fuel cells, the energy conversion efficiencies of ORR and OER are greatly affected by their reaction kinetics. In addition to designing excellent electrocatalysts, new methods to stabilize the electrolyte/electrode interfaces are urgently needed. Herein, a hierarchical Co(OH)F/CuCo2S4 hybrid was created as an efficient catalyst for OER and ORR in alkaline media. Combining spinel ferrite with the hydroxide can greatly boost their catalytic performance. The optimal Co(OH)F/CuCo2S4 hybrid exhibits superior OER performance and durable stability, as demonstrated by an ultralow overpotential of 230 mV at 10 mA·cm-2. The onset potential and half-wave potential in 0.1 M KOH solution for ORR are 0.88 V and 0.80 V, respectively. Furthermore, the Co(OH)F/CuCo2S4 hybrid served as Zn air batteries catalyst exhibits a low overpotential of 1.12 V at 50.0 mA·cm-2 , large power density of 144 mW·cm-2, and a long electrochemical lifetime with 118 h (118 cycles), which is even better than the Pt/C and RuO2 catalysts. The rational integration of spinel and hydroxide at the interface can achieve multifunctional electrocatalysis and possess high reactivity for oxygen conversion. Synergistic coupling effect and interfacial electronic interaction between Co(OH)F and CuCo2S4 can significantly enhance the electron transfer rate, and these synergistic advantages enable the heterogeneous structure of the multifunctional electrocatalyst to achieve excellent catalytic performance.

4.
Opt Lett ; 44(18): 4590-4593, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31517938

RESUMO

Surface plasmon resonance (SPR) is a powerful tool to amplify coherent phonon signals in metal films. In a 40 nm Au film excited with a 400 nm pump, we observed an abnormally large electron-phonon coupling constant of about 8×1017 W/(m3K), almost 40× larger than those reported in noble metals, and even comparable to transition metals. We attribute this phenomenon to quantum confinement and interband excitation. With SPR, we also observed two coherent phonon modes in a GaAs/AlAs quantum well thin film. Our finding provides a new approach to generate high-frequency acoustic phonons in noble metals and to study their nonlinear nature of propagation.

5.
Eur J Pharm Sci ; : 105036, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31446078

RESUMO

Graphene oxide (GO) has attracted huge attention in biomedical field in recent years. However, limited attempts have been invested in utilizing GO on active targeted delivery for gene therapy in liver cancer treatments. Glycyrrhetinic acid (GA) has been reported to be widely used as a targeting ligand to functionalize nanomaterials to treat hepatocellular carcinoma. In this article, GA is employed as a liver targeting ligand to construct GA, polyethylene glycol (PEG), polyamidoamine dendrimer (Dendrimer) and nano-graphene oxide (NGO) conjugate (GA-PEG-NGO-Dendrimer, GPND) for siRNA delivery for the first time. As we expected, GPND exhibited excellent stability, low toxicity, negligible hemolytic activity and remarkably high transfection efficiency in vitro. We also found effective VEGFa gene silencing in both mRNA and protein level in HepG2 cells. Notably, siRNA efficiently gathered in liver tumor tissues by the delivery of GPND, and eventually the growth of tumor tissues were inhibited with enhanced targeting capability and no obvious pathological changes. Moreover, histopathological results preliminarily support the high in vivo safety of GPND/anti-VEGFa siRNA nanocomplex. Collectively, GPND/siRNA nanocomplex, with high safety, targeting and transfection as well as prolonged half-life, is a promising nanomedicine and may provide a new direction for highly-specific targeted gene therapy.

7.
Medicine (Baltimore) ; 98(35): e16975, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464943

RESUMO

BACKGROUND: Significant functional limitations and disabilities are common presenting complaints for people suffering from cervical radiculopathy. Exercise is a common conservative treatment for this disease. Therefore, we conducted a systematic review and meta-analysis to explore the efficacy of exercise in the treatment of cervical radiculopathy. METHODS: A systematic literature search for studies will be performed in 7 databases, including PubMed, Web of Science, Embase, the Cochrane Library, the Chinese National Knowledge Infrastructure Database (CNKI), Wanfang database, and VIP database. The methodological quality of the included studies using the risk bias assessment tool of Cochrane and the level of evidence for results are assessed by the GRADE method. Statistical analysis is conducted with Revman 5.3. RESULTS: This systematic review and meta-analysis will provide a synthesis of existed evidences for exercise on cervical radiculopathy. CONCLUSION: The conclusion of this study will provide evidence to assess effectiveness of exercise on cervical radiculopathy, which can further guide clinical decision-making. PROSPERO REGISTRATION NUMBER: CRD42019121886.

8.
Adv Exp Med Biol ; 1155: 533-541, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468429

RESUMO

Taurine displays anti-tumor activity in some kinds of human cancers. However, the underlying mechanisms are poorly understood. Epstein-Barr virus-related nasopharyngeal carcinoma (NPC) is a distinctive type of head and neck cancer in Southeast Asia with the highest incidence in South China. We examined an apoptosis-inducing effect of taurine against NPC cells (HK1 and HK1-EBV) to clarify the mechanisms of anti-tumor effects of taurine by immunocytochemical methods. We observed that taurine induced cleavage of caspase-9/3 in a concentration-dependent manner, suggesting the involvement of mitochondrial apoptotic signals. Both PTEN and p53 activation were detected in a dose-dependent manner after taurine treatment in NPC cells. In conclusion, taurine may play an anti-tumor role by activating tumor suppressor PTEN and p53.

9.
J Phys Chem Lett ; 10(16): 4737-4743, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31370396

RESUMO

Two chlorine-substituted isomers, ITIC-2Cl-ß and a-ITIC-2Cl, were synthesized for potential use as nonfullerene acceptors. The two molecules differ in the position of chlorine atoms, leading to symmetric (ITIC-2Cl-ß) and asymmetric (a-ITIC-2Cl) molecular configuration. In single crystals, the two molecules exhibit a completely different arrangement and stacking as derived from X-ray diffraction analysis. Whereas ITIC-2Cl-ß has a linear packing structure, a-ITIC-2Cl forms a 3D interpenetrating network structure with shorter π-π distances and better molecular planarity. Therefore, a high power conversion efficiency of >12% is obtained by a-ITIC-2Cl-based devices. It is ∼10% higher than that of ITIC-2Cl-ß-based devices due to the chlorine substituent effect. Thus the fine-tuning of the Cl-substituted position seems to be a promising strategy to construct a 3D interpenetrating charge transportation network and achieve higher performance organic solar cells (OSCs).

10.
Nutrients ; 11(8)2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31382636

RESUMO

The study aimed to compare the sugar (1992, 2017) and energy (2017) content of chocolate confectionery available in the UK between 1992 and 2017 using cross-sectional surveys. All major UK retailers operating at the time were included. Sugar content in 1992 was obtained from a booklet and sugar and energy content from 2017 were collected from product packaging in-store. In 1992, the average sugar content of chocolate confectionery was 46.6 ± 10.3 g/100 g and in 2017 it was 47.3 ± 12.1 g/100 g. Sugar content ranged from 0.5 to 75.2 g/100g, with large variations between different categories of chocolate and within the same category of chocolate. There were 23 products found in both 1992 and 2017. The average sugar content per 100 g for these products was 44.6 ± 9.4 g in 1992 and 54.7 ± 6.3 g in 2017, representing a 23% increase in sugar content (p < 0.001). The results show that the sugar content of chocolate confectionery has increased since 1992, which is concerning. However, they also suggest sugar levels can be reduced because (a) lower sugar versions of the same products existed in 1992 and (b) there is a large variation in sugar and energy content between different categories of chocolate and within the same category in 2017.

11.
J Neural Eng ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31365911

RESUMO

OBJECTIVE: We proposed a brain-computer interface (BCI) based visual-haptic neurofeedback training (NFT) by incorporating synchronous visual scene and proprioceptive electrical stimulation feedback. The goal of this work was to improve sensorimotor cortical activations and classification performance during motor imagery (MI). In addition, their correlations and brain network patterns were also investigated respectively. APPROACH: 64-channel electroencephalographic (EEG) data were recorded in nineteen healthy subjects during MI before and after NFT. During NFT sessions, the synchronous visual-haptic feedbacks were driven by real-time lateralized relative event-related desynchronization (lrERD). MAIN RESULTS: By comparison between previous and posterior control sessions, the cortical activations measured by multi-band (i.e. alpha_1: 8-10Hz, alpha_2: 11-13Hz, beta_1: 15-20Hz and beta_2: 22-28Hz) absolute ERD powers and lrERD patterns were significantly enhanced after the NFT. The classification performance was also significantly improved, achieving a ~9% improvement and reaching ~85% in mean classification accuracy from a relatively poor performance. Additionally, there were significant correlations between lrERD patterns and classification accuracies. The partial directed coherence (PDC) based functional connectivity (FC) networks covering the sensorimotor area also showed an increase after the NFT. SIGNIFICANCE: These findings validate the feasibility of our proposed NFT to improve sensorimotor cortical activations and BCI performance during motor imagery. And it is promising to optimize conventional NFT manner and evaluate the effectiveness of motor training.

12.
Nat Commun ; 10(1): 2942, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270312

RESUMO

Depression and transient ischaemic attack represent the common psychological and neurological diseases, respectively, and are tightly associated. However, studies of depression-affected ischaemic attack have been limited to epidemiological evidences, and the neural circuits underlying depression-modulated ischaemic injury remain unknown. Here, we find that chronic social defeat stress (CSDS) and chronic footshock stress (CFS) exacerbate CA1 neuron loss and spatial learning/memory impairment after a short transient global ischaemia (TGI) attack in mice. Whole-brain mapping of direct outputs of locus coeruleus (LC)-tyrosine hydroxylase (TH, Th:) positive neurons reveals that LC-CA1 projections are decreased in CSDS or CFS mice. Furthermore, using designer receptors exclusively activated by designer drugs (DREADDs)-based chemogenetic tools, we determine that Th:LC-CA1 circuit is necessary and sufficient for depression-induced aggravated outcomes of TGI. Collectively, we suggest that Th:LC-CA1 pathway plays a crucial role in depression-induced TGI vulnerability and offers a potential intervention for preventing depression-related transient ischaemic attack.

13.
J Neurotrauma ; 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31354055

RESUMO

Pre-clinical studies of traumatic brain injury (TBI) show that glyburide reduces edema and hemorrhagic progression of contusions. We conducted a small Phase II, three-institution, randomized placebo-controlled trial of subjects with TBI to assess the safety and efficacy of intravenous (IV) glyburide. Twenty-eight subjects were randomized and underwent a 72-h infusion of IV glyburide or placebo, beginning within 10 h of trauma. Of the 28 subjects, 25 had Glasgow Coma Scale (GCS) scores of 6-10, and 14 had contusions. There were no differences in adverse events (AEs) or severe adverse events (ASEs) between groups. The magnetic resonance imaging (MRI) percent change at 72-168 h from screening/baseline was compared between the glyburide and placebo groups. Analysis of contusions (7 per group) showed that lesion volumes (hemorrhage plus edema) increased 1036% with placebo versus 136% with glyburide (p = 0.15), and that hemorrhage volumes increased 11.6% with placebo but decreased 29.6% with glyburide (p = 0.62). Three diffusion MRI measures of edema were quantified: mean diffusivity (MD), free water (FW), and tissue MD (MDt), corresponding to overall, extracellular, and intracellular water, respectively. The percent change with time for each measure was compared in lesions (n = 14) versus uninjured white matter (n = 24) in subjects receiving placebo (n = 20) or glyburide (n = 18). For placebo, the percent change in lesions for all three measures was significantly different compared with uninjured white matter (analysis of variance [ANOVA], p < 0.02), consistent with worsening of edema in untreated contusions. In contrast, for glyburide, the percent change in lesions for all three measures was not significantly different compared with uninjured white matter. Further study of IV glyburide in contusion TBI is warranted.

14.
Thyroid ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31347461

RESUMO

Background: Subclinical thyroid disease occurs in approximately 5-8% of all pregnancies and is associated with a higher risk of adverse outcomes such as miscarriage, preterm birth, and suboptimal child neurodevelopment. It is generally assumed that subclinical thyroid disease that persists from early to late pregnancy is associated with a higher risk of adverse outcomes than transient disease. However, it is unknown as to what percentage of women with subclinical disease during early pregnancy have persistent disease in the third trimester. Methods: This study comprised 42,492 mothers for whom early and late pregnancy thyrotropin (TSH), free thyroxine (fT4), triiodothyronine (T3), or TPOAbs were available and who did not receive thyroid treatment before or during pregnancy. We adjusted for potential confounders, including maternal age, parity, anthropometrics, and ß-hCG concentrations. Results: Subclinical hypothyroidism and hypothyroxinemia persisted in 24.8% and 17.7% of cases. Overt hyperthyroidism persisted in 8.4% of cases while subclinical hyperthyroidism persisted in 20.9% of cases. Low T3 persisted in 43.4% of cases while elevated T3 persisted in 15.7% of cases. TPOAb positivity persisted in 84.0% of cases. In women with subclinical hypothyroidism, a TSH below ∼5 mU/L at the time of diagnosis was associated with an up to 50% lower risk of persistency. The fT4 concentration at diagnosis predicted hyperthyroidism persistency and TPOAb positivity predicted persistency of all disease entities. Conclusions: Early pregnancy thyroid disease only persists until the third trimester in 8.4-24.8% of cases when left untreated. The main predictor for persistency is TPOAb positivity, with TPOAb-positive women having a lower risk that subclinical hypothyroidism or hypothyroxinemia persists, but a higher risk that (subclinical) hyperthyroidism persists.

15.
Fish Shellfish Immunol ; 92: 782-791, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31288100

RESUMO

Toll-like receptor (TLR) genes are the earliest reported pathogen recognition receptors (PRRs) and have been extensively studied. These genes play pivotal roles in the innate immune defense against pathogen invasion. In this study, a total of 16 tlr genes were identified and characterized in spotted sea bass (Lateolabrax maculatus). The tlr genes of spotted sea bass were classified into five subfamilies (tlr1-subfamily, tlr3-subfamily, tlr5-subfamily, tlr7-subfamily, and tlr11-subfamily) according to the phylogenetic analysis, and their annotations were confirmed by a syntenic analysis. The protein domain analysis indicated that most tlr genes had the following three major TLR protein domains: a leucine-rich repeat (LRR) domain, a transmembrane region (TM) and a Toll/interleukin-1 receptor (TIR) domain. The tlr genes in spotted sea bass were distributed in 11 of 24 chromosomes. The mRNA expression levels of 16 tlr genes in response to Vibrio harveyi infection were quantified in the head kidney. Most genes were downregulated following V. harveyi infection, while only 5 tlr genes, including tlr1-1, tlr1-2, tlr2-2, tlr5, and tlr7, were significantly upregulated. Collectively, these results help elucidate the crucial roles of tlr genes in the immune response of spotted sea bass and may supply valuable genomic resources for future studies investigating fish disease management.

16.
PLoS Genet ; 15(7): e1008299, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31335872

RESUMO

[This corrects the article DOI: 10.1371/journal.pgen.1007806.].

17.
BMJ Open ; 9(7): e027793, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31272977

RESUMO

INTRODUCTION: Salt intake is very high in China, with ≈80% being added by the consumers. It is difficult to reduce salt in such settings. Our previous study (School-based Education programme to reduce Salt(School-EduSalt)) demonstrated that educating schoolchildren, who then instructed their families to reduce the amount of salt used at home, is effective in lowering salt intake in both children and adults. Our team also developed an app called 'KnowSalt', which could help individuals to estimate their salt intake and the major sources of salt in the diet. Building on School-EduSalt and KnowSalt, we propose to develop a new app (AppSalt) focusing on salt reduction through education, target setting, monitoring, evaluation, decision support and management to achieve a progressive lower salt intake for long term. To evaluate the effectiveness of the AppSalt programme, we will carry out a cluster randomised controlled trial. METHODS AND ANALYSIS: We will recruit 54 primary schools from urban and rural areas of three provinces in China. A total of 594 children aged 8-9 years and 1188 adult family members will be randomly selected for evaluation. After baseline assessment, schools will be randomly allocated to either the intervention or control group. Children in the intervention group will be taught, with support of AppSalt, about salt reduction and assigned homework to get the whole family involved in the activities to reduce salt consumption. The duration of the intervention is two school terms (ie, 1 year). The primary outcome is the difference between the intervention and control group in the change of salt intake as measured by 24-hour urinary sodium. ETHICS AND DISSEMINATION: The study has been approved by Queen Mary Research Ethics Committee and Peking University Health Science Centre IRB. Results will be disseminated through presentations, publications and social media. TRIAL REGISTRATION NUMBER: ChiCTR1800017553.

19.
Invest Ophthalmol Vis Sci ; 60(8): 2861-2874, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260037

RESUMO

Purpose: Phosphatidylinositol-3-phosphate (PI(3)P), and Vps34, the type III phosphatidylinositol 3-kinase primarily responsible for its production, are important for function and survival of sensory neurons, where they have key roles in membrane processing events, such as autophagy, endosome processing, and fusion of membranes bearing ubiquitinated cargos with lysosomes. We examined their roles in the most abundant class of secondary neurons in the vertebrate retina, the ON-bipolar cells (ON-BCs). Methods: A conditional Vps34 knockout mouse line was generated by crossing Vps34 floxed mice with transgenic mice expressing Cre recombinase in ON-BCs. Structural changes in the retina were determined by immunofluorescence and electron microscopy, and bipolar cell function was determined by electroretinography. Results: Vps34 deletion led to selective death of ON-BCs, a thinning of the inner nuclear layer, and a progressive decline of electroretinogram b-wave amplitudes. There was no evidence for loss of other retinal neurons, or disruption of rod-horizontal cell contacts in the outer plexiform layer. Loss of Vps34 led to aberrant accumulation of membranes positive for autophagy markers LC3, p62, and ubiquitin, accumulation of endosomal membranes positive for Rab7, and accumulation of lysosomes. Similar effects were observed in Purkinje cells of the cerebellum, leading to severe and progressive ataxia. Conclusions: These results support an essential role for PI(3)P in fusion of autophagosomes with lysosomes and in late endosome maturation. The cell death resulting from Vps34 knockout suggests that these processes are essential for the health of ON-BCs.

20.
iScience ; 17: 302-314, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31323476

RESUMO

The influence caused by the position of the chlorine atom on end groups of two non-fullerene acceptors (ITIC-2Cl-δ and ITIC-2Cl-γ) was intensely investigated. The single-crystal structures show that ITIC-2Cl-γ has a better molecular planarity and closer π-π interaction distance. More importantly, a 3D rectangle-like interpenetrating network is formed in ITIC-2Cl-γ and is beneficial to rapid charge transfer along multiple directions, whereas only a linear stacked structure could be observed in ITIC-2Cl-δ. The two acceptor-based solar cells show power conversion efficiencies (PCEs) over 11%, higher than that of the ITIC-2Cl-m-based device (10.85%). An excellent PCE of 13.03% is obtained by the ITIC-2Cl-γ-based device. In addition, the ITIC-2Cl-γ-based device also shows the best device stability. This study indicates that chlorine positioning has a great impact on the acceptors; more importantly, the 3D network structure may be a promising strategy for non-fullerene acceptors to improve the PCE and stability of organic solar cells.

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