Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 293
Filtrar
1.
Nat Commun ; 11(1): 2177, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358581

RESUMO

Brain tumors (gliomas) are heterogeneous cellular ecosystems, where non-neoplastic monocytic cells have emerged as key regulators of tumor maintenance and progression. However, relative to macrophages/microglia, comparatively less is known about the roles of neurons and T cells in glioma pathobiology. Herein, we leverage genetically engineered mouse models and human biospecimens to define the axis in which neurons, T cells, and microglia interact to govern Neurofibromatosis-1 (NF1) low-grade glioma (LGG) growth. NF1-mutant human and mouse brain neurons elaborate midkine to activate naïve CD8+ T cells to produce Ccl4, which induces microglia to produce a key LGG growth factor (Ccl5) critical for LGG stem cell survival. Importantly, increased CCL5 expression is associated with reduced survival in patients with LGG. The elucidation of the critical intercellular dependencies that constitute the LGG neuroimmune axis provides insights into the role of neurons and immune cells in controlling glioma growth, relevant to future therapeutic targeting.

2.
Transl Neurodegener ; 9(1): 18, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398165

RESUMO

BACKGROUND: Neuropsychiatric symptoms (NPS) such as depression, anxiety, apathy, and irritability occur in prodromal phases of clinical Alzheimer's disease (AD), which might be an increased risk for later developing AD. Here we treated young APP/PS1 AD model mice prophylactically with serotonin-selective re-uptake inhibitor (SSRI) paroxetine and investigated the protective role of anti-depressant agent in emotional abnormalities and cognitive defects during disease progress. METHODS: To investigate the protective role of paroxetine in emotional abnormalities and cognitive defects during disease progress, we performed emotional behaviors of 3 months old APP/PS1 mouse following oral administration of paroxetine prophylactically starting at 1 month of age. Next, we tested the cognitive, biochemical and pathological, effects of long term administration of paroxetine at 6 months old. RESULTS: Our results showed that AD mice displayed emotional dysfunction in the early stage. Prophylactic administration of paroxetine ameliorated the initial emotional abnormalities and preserved the eventual memory function in AD mice. CONCLUSION: Our data indicate that prophylactic administration of paroxetine ameliorates the emotional dysfunction and memory deficit in AD mice. These neuroprotective effects are attributable to functional restoration of glutamate receptor (GluN2A) in AD mice.

3.
JMIR Mhealth Uhealth ; 8(2): e16063, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32130165

RESUMO

BACKGROUND: There are numerous mobile apps for tracking work hours, but only a few of them record work hours automatically instead of relying on manual logging. No apps have been customized for medical staff, whose work schedules are highly complicated as they have both regular hours and on-call duties. OBJECTIVE: The specific aims of this study were to (1) identify the Staff Hours app users' GPS-defined work hours, (2) examine the overtime work hours from the app-recorded total work hours and the participants' self-reported scheduled work hours, and (3) compare these app-recorded total work hours among different occupations. METHODS: We developed an app, Staff Hours, to automatically calculate a user's work hours via GPS background data. Users can enter their scheduled hours, including regular hours and on-call duties. The app automatically generates overtime reports by comparing the app-recorded total work hours with the user-defined scheduled hours. A total of 183 volunteers (60 females and 123 males; mean age 32.98 years, SD 6.74) were included in this study. Most of the participants (162/183, 88.5%) were medical staff, and their positions were resident physicians (n=89), visiting staff (n=38), medical students (n=10), registered nurses (n=25), and non-health care professionals (non-HCPs; n=21). RESULTS: The total work hours (mean 55.69 hours, SD 21.34) of the 183 participants were significantly higher than their scheduled work hours (mean 50.67 hours, SD 21.44; P=.01). Medical staff had significantly longer total work hours (mean 57.01 hours, SD 21.20) than non-HCPs (mean 45.48 hours, SD 20.08; P=.02). Residents (mean 60.38 hours, SD 18.67) had significantly longer work hours than visiting staff (mean 51.42 hours, SD 20.33; P=.03) and non-HCPs (mean 45.48 hours, SD 20.08; P=.004). CONCLUSIONS: Staff Hours is the first automatic GPS location-based app designed for medical staff to track work hours and calculate overtime. For medical staff, this app could keep complete and accurate records of work hours in real time, reduce bias, and allow for better complying with labor regulations.

4.
Biomolecules ; 10(2)2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32023953

RESUMO

Inflammation-induced angiogenesis is closely related to many diseases and has been regarded as a therapeutic target. Caspase-8 has attracted increasing attention for its immune properties and therapeutic potential in inflammatory disorders. The aim of our study is to investigate the clinical application of pharmacological inhibition of caspase-8 and the underlying molecular mechanisms in inflammation-induced angiogenesis in the cornea. A model of alkali burn (AB)-induced corneal neovascularization (CNV) in C57BL/6 wild-type (WT) mice and toll-like receptor 4 knockout (Tlr4-/-) mice was used. We found that AB increased caspase-8 activity and the pharmacological inhibition of caspase-8 exerted substantial inhibitory effects on CNV, with consistent decreases in caspase-8 activity, inflammatory cell infiltration, macrophage recruitment and activation, VEGF-A, TNF-α, IL-1ß, MIP-1, and MCP-1 expression in the cornea. In vitro, caspase-8 mediated TLR4-dependent chemokines and VEGF-A production by macrophages. The TLR4 knockout significantly alleviated CNV, suppressed caspase-8 activity and downregulated expression of inflammatory cytokines and chemokines after AB. Taken together, these findings provide the first demonstration that the pharmacological inhibition of caspase-8 suppresses inflammation-induced angiogenesis and support the use of a pharmacological caspase-8 inhibitor as a novel clinical treatment for CNV and other angiogenic disorders.

5.
J Cell Mol Med ; 24(7): 3901-3916, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32091665

RESUMO

Using molecular signatures, previous studies have defined glioblastoma (GBM) subtypes with different phenotypes, such as the proneural (PN), neural (NL), mesenchymal (MES) and classical (CL) subtypes. However, the gene programmes underlying the phenotypes of these subtypes were less known. We applied weighted gene co-expression network analysis to establish gene modules corresponding to various subtypes. RNA-seq and immunohistochemical data were used to validate the expression of identified genes. We identified seven molecular subtype-specific modules and several candidate signature genes for different subtypes. Next, we revealed, for the first time, that radioresistant/chemoresistant gene signatures exist only in the PN subtype, as described by Verhaak et al, but do not exist in the PN subtype described by Phillips et al PN subtype. Moreover, we revealed that the tumour cells in the MES subtype GBMs are under ER stress and that angiogenesis and the immune inflammatory response are both significantly elevated in this subtype. The molecular basis of these biological processes was also uncovered. Genes associated with alternative RNA splicing are up-regulated in the CL subtype GBMs, and genes pertaining to energy synthesis are elevated in the NL subtype GBMs. In addition, we identified several survival-associated genes that positively correlated with glioma grades. The identified intrinsic characteristics of different GBM subtypes can offer a potential clue to the pathogenesis and possible therapeutic targets for various subtypes.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31910026

RESUMO

The present study examined the mechanism of a low protein (LP) diet on hepatic lipid metabolism during gestation and lactation. Timed-pregnant Sprague-Dawley rats were fed a control or an LP diet during gestation and lactation. LP dams had increased hepatic triglyceride accumulation and significantly higher aspartate/alanine transaminase ratio, accompanied by a decrease in circulating very low-density/low-density lipoprotein ratio. LC3B (Microtubule Associated Protein 1 Light Chain 3 Beta) expression was stimulated in LP dams along with increased histone acetylation. LP diet-induced co-localization of the LC3 binding motif-interacting proteins APOB or MTTP with LC3B, suggesting autophagic degradation. HDAC3 is found necessary to prevent lipid accumulation in response to amino acid deprivation in HepG2 cells. LC3B-mediated APOB protein degradation is related to increases in lipid accumulation. Conclusion: HDAC3 regulated LC3B-induced lipid accumulation potentially through autophagic degradation of APOB and MTTP in response to amino acid limitation caused by a low protein diet.

7.
J Neurosci ; 40(5): 944-954, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996470

RESUMO

The brilliant and often prescient hypotheses of Ramon y Cajal have proven foundational for modern neuroscience, but his statement that "In adult centers the nerve paths are something fixed, ended, immutable … " is an exception that did not stand the test of empirical study. Mechanisms of cellular and circuit-level plasticity continue to shape and reshape many regions of the adult nervous system long after the neurodevelopmental period. Initially focused on neurons alone, the field has followed a meteoric trajectory in understanding of activity-regulated neurodevelopment and ongoing neuroplasticity with an arc toward appreciating neuron-glial interactions and the role that each neural cell type plays in shaping adaptable neural circuity. In this review, as part of a celebration of the 50th anniversary of Society for Neuroscience, we provide a historical perspective, following this arc of inquiry from neuronal to neuron-glial mechanisms by which activity and experience modulate circuit structure and function. The scope of this consideration is broad, and it will not be possible to cover the wealth of knowledge about all aspects of activity-dependent circuit development and plasticity in depth.


Assuntos
Encéfalo/metabolismo , Rede Nervosa/metabolismo , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Animais , Encéfalo/citologia , Humanos , Rede Nervosa/citologia
8.
Am J Physiol Regul Integr Comp Physiol ; 318(3): R515-R528, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31940232

RESUMO

The simultaneous introduction of wheel running (WR) and diet choice (high-carbohydrate chow vs. high-fat diet) results in sex-specific diet choice patterns in rats. WR induces a high-fat (HF) diet avoidance, and such avoidance persists in the majority of males, but not females, throughout a 2-wk period. Exercise is a physiological stressor that activates the hypothalamic-pituitary-adrenal (HPA) axis and stimulates glucocorticoid (GC) release, which can alter dietary preferences. Here, we examined the role of the HPA axis and GC signaling in mediating exercise-induced changes in diet preference and the associated neurobiological adaptations that may underlie sex differences in diet choice patterns. Experiment 1 revealed that adrenalectomy did not significantly alter the initiation and persistence of running-induced HF diet avoidance in male rats. Experiment 2 showed that acute WR resulted in greater neural activation than chronic WR in the medial prefrontal (mPFC) and insular cortices (IC) in male rats. Experiment 3 revealed sex differences in the molecular adaptation to exercise and diet preference. First, exercise increased gene expression of fkbp5 in the mPFC, IC, and hippocampus of WR females but had limited influence in males. Second, male and female WR rats that reversed or maintained HF diet avoidance showed distinct sex- and HF diet preference-dependent expression profiles of genes involved in cortical GC signaling (e.g., nr3c1, nr3c2, and src1). Taken together, our results suggest sex differences in region-specific neural adaptations may underlie sex differences in diet preference and the health benefits from exercise.

9.
FEBS J ; 287(1): 190-204, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31365784

RESUMO

A disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) is a metalloproteinase known to modulate the progression of several types of tumor. However, the role played by ADAM10 in pituitary adenomas is currently unknown, and what factors orchestrate the activation of ADAM10 in this kind of tumor is also unclear. Here, we found that SRC kinase is an ADAM10-interacting partner and that SRC kinase activity is required for this interaction. As a new positive regulator promoting the shedding activity of ADAM10, SRC could compete with calmodulin 1 (CALM1) for ADAM10 binding in a mutually exclusive manner. Strikingly, the interaction between ADAM10 and CALM1 is regulated by SRC activity. Furthermore, we proved that the cytoplasmic region of ADAM10 is required for the shedding activity of ADAM10 upon SRC activation. As a proof-of-concept, we discovered that the combination of ADAM10 and SRC inhibitors can inhibit cell proliferation and migration to a great extent. Thus, our findings shed light on a novel therapeutic strategy to block the tumorigenesis and migration of pituitary adenoma.

10.
J Pharm Pharmacol ; 72(3): 461-469, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31858612

RESUMO

OBJECTIVE: To investigate the effect of GSK-137647A, the first non-carboxylic FFA4 agonist, on osteogenic and adipogenic differentiation of bone mesenchymal stem cells (BMSCs) of db/db mice. METHODS: Bone mesenchymal stem cells were extracted from 8-week-old db/db mice. Cell Counting Kit-8 was used to evaluate the toxicity of GSK-137647A on BMSCs, and the optimal concentration of GSK-137647A was selected to investigate the osteogenic and adipogenic differentiation of BMSCs, and relevant indicators of osteoblasts and adipocytes were detected. KEY FINDINGS: GSK-137647A had no significant toxicity on cell growth and proliferation. Moreover, GSK-137647A showed a significant increase in mineralization of BMSCs differentiated osteoblasts compared to the control group and elevated the alkaline phosphatase (ALP) activity in a time-dependent manner. Meanwhile, the treatment of GSK-137647A decreased the adipogenic differentiation of BMSCs. The expression levels of ALP, runt-related transcription factor 2, bone morphogenetic protein 4, osterix and ß-catenin were significantly increased in GSK-137647A-treated group, while the gene and protein levels of peroxisome proliferator-activated receptor γ and CCAAT/enhancer binding protein α were significantly reduced. CONCLUSIONS: All of these results demonstrated that GSK-137647A suppressed the adipogenic differentiation and promoted osteogenic differentiation of BMSCs, which is partly attributed to the increased expression of ß-catenin in wingless/integrated signalling pathway.

11.
Oncol Lett ; 18(6): 6079-6089, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31788082

RESUMO

Ependymomas (EPNs) are one of the most common types of malignant neuroepithelial tumors. In an effort to identify potential biomarkers involved in the pathogenesis of EPN, the mRNA expression profiles of the GSE25604, GSE50161, GSE66354, GSE74195 and GSE86574 datasets, in addition to the microRNA (miRNA/miR) expression profiles of GSE42657 were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) between EPN and normal brain tissue samples were identified using the Limma package in R and GEO2R, respectively. Functional and pathway enrichment analyses were conducted using the Database for Annotation, Visualization and Integrated Discovery. A protein-protein interaction network was constructed using the Search Tool for Retrieval of Interacting Genes database, which was visualized using Cytoscape. The targeted genes of DEMs were predicted using miRWalk2.0 and a miRNA-mRNA regulatory network was constructed. Following analysis, a total of 948 DEGs and 129 DEMs were identified. Functional enrichment analysis revealed that 609 upregulated DEGs were significantly enriched in 'PI3K-Akt signaling pathway', while 339 downregulated DEGs were primarily involved in 'cell junction' and 'retrograde endocannabinoid signaling'. In addition, 6 hub genes [cyclin dependent kinase 1, CD44 molecule (Indian blood group) (CD44), proliferating cell nuclear antigen (PCNA), MYC, synaptotagmin 1 (SYT1) and kinesin family member 4A] and 6 crucial miRNAs [homo sapiens (hsa)-miR-34a-5p, hsa-miR-449a, hsa-miR-106a-5p, hsa-miR-124-3p, hsa-miR-128-3p and hsa-miR-330-3p] were identified as biomarkers and potential therapeutic targets for EPN. Furthermore, a microRNA-mRNA regulatory network was constructed to highlight the interactions between DEMs and their target DEGs; this included the hsa-miR-449a-SYT1, hsa-miR-34a-5p-SYT1, hsa-miR-330-3p-CD44 and hsa-miR-124-3p-PCNA pairs, whose expression levels were confirmed using reverse transcription-quantitative polymerase chain reaction. In conclusion, the present study may provide important data for the investigation of the molecular mechanisms of EPN pathogenesis.

12.
Zhongguo Zhen Jiu ; 39(12): 1289-93, 2019 Dec 12.
Artigo em Chinês | MEDLINE | ID: mdl-31820604

RESUMO

OBJECTIVE: To observe the effect of acupoint stimulation on the quality of recovery in patients with radical thyroidectomy under the concept of enhanced recovery after surgery (ERAS). METHODS: A total of 62 patients with radical thyroidectomy were randomized into an observation group and a control group, 31 cases in each one. In both of the two groups, general anesthesia with tracheal intubation was applied, the same anesthesia induction and maintenance medication were given. In the observation group, auricular point pressing with magnetic beads was adopted at bilateral shenmen (TF4) and transcutaneous electrical acupoint stimulation (dilatational wave, 2 Hz/100 Hz in frequency, 6 to 12 mA) was performed at bilateral Hegu (LI 4) and Neiguan (PC 6) from 30 min before anesthesia induction to the end of the anesthesia. In the control group, medical adhesive plaster was pasted at bilateral shenmen (TF4) and the electrodes were plastered at bilateral Hegu (LI 4) and Neiguan (PC 6) with no corresponding stimulation. In both of the two groups, visual analogue scale for anxiety (VAS-A) score was observed to evaluate the anxiety severity before anesthesia induction; the total intraoperative dosages of sufentanil, remifentanil and propofol were recorded; the numerical rating scale (NRS) score was used to assess the pain severity of instant time (T0) and 30 min (T1) of entering post-anesthesia recovery room (PACU), motor and static mode at 2 h (T2), 6 h (T3), 12 h (T4), 24 h (T5) after surgery; time of first anal exhaust, time of getting out of bed after surgery, total hospitalization time and the incidences of postoperative nausea and vomiting were observed; the quality of recovery was assessed by the 40-item quality of recovery score (QoR-40). RESULTS: The VAS-A score and the total intraoperative dosage of remifentanil in the observation group were reduced compared with the control group (P<0.05). The NRS scores at T0-T4 in the observation group were lower than those in the control group (P<0.01, P<0.05), while the difference between the two groups in NRS score at T5 was not significant (P>0.05). The time of first anal exhaust and getting out of bed after surgery in the observation group were advanced than those in the control group (P<0.05), there was no significant difference between the two groups in total hospitalization time and incidences of postoperative nausea and vomiting (P>0.05). Compared with the control group, the QoR-40 score was increased in the observation group (P<0.05). CONCLUSION: Acupoint stimulation can improve the preoperative anxiety in patients with radical thyroidectomy, reduce the intraoperative anesthetic dosage and postoperative pain, advance the time of anal exhaust and getting out of bed, improve the quality of postoperative recovery and enhance the recovery process.


Assuntos
Pontos de Acupuntura , Humanos , Náusea e Vômito Pós-Operatórios , Tireoidectomia , Estimulação Elétrica Nervosa Transcutânea
14.
J Mater Chem B ; 7(48): 7683-7689, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31778139

RESUMO

The success of glioma chemotherapy is hampered by low intratumoral drug concentration and severe toxicity in normal organs. Glioma diagnosis and total tumor resection depend on enhanced magnetic resonance imaging (MRI) results which provide the best solution for recognizing tumor mass anatomical details with high spatial resolution. Zeolite imidazole frameworks (ZIFs) have pore channel tunability, large specific surface area and porosity, and have broad application prospects in adsorption, catalysis and drug loading. However, there are few reports on post-synthesis ZIF-8 based multifunctional nanocomposites as a theranostic agent for in vivo diagnostic and therapeutic applications simultaneously. In this study, we synthesized a low toxicity bimetallic zeolitic imidazolate framework (Mn-ZIF-8) with good dispersibility and high specific surface area, which could be used for potential high drug loading. Meanwhile, we used Mn-ZIF-8 for the first time for in vivo MRI. T1-weighted MR signals at tumor sites continuously increased over time after injecting Mn-ZIF-8 intravenously. Moreover, 12 hours after injecting Mn-ZIF-8 into a nude mouse bearing U87-MG tumor, a relatively high accumulation of Mn2+ in tumors was observed, probably due to the EPR effect of cancerous tumors. Targeted delivery significantly improves the therapeutic efficacy of Mn-ZIF-8/5-Fu in U87-MG tumor-bearing mice, resulting in 80% survival rate over 40 days of treatment. Mn-ZIF-8/5-Fu has excellent in vivo biocompatibility at a given dose, which induces minimal side effects on the functions of important organs. Therefore, efficient 5-Fu loaded Mn-ZIF-8 with favorable in vivo biocompatibility, pH responsiveness and T1-weighted contrast MRI of tumors can be used as a promising framework for diagnostic and therapeutic applications in the case of glioma simultaneously.

15.
BMC Genomics ; 20(1): 877, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747870

RESUMO

BACKGROUND: Cadmium (Cd) is a serious heavy metal (HM) soil pollutant. To alleviate or even eliminate HM pollution in soil, environmental-friendly methods are applied. One is that special plants are cultivated to absorb the HM in the contaminated soil. As an excellent economical plant with ornamental value and sound adaptability, V. bonariensis could be adapted to this very situation. In our study, the Cd tolerance in V. bonariensis was analyzed as well as an overall analysis of transcriptome. RESULTS: In this study, the tolerance of V. bonariensis to Cd stress was investigated in four aspects: germination, development, physiological changes, and molecular alterations. The results showed that as a non-hyperaccumulator, V. bonariensis did possess the Cd tolerance and the capability to concentration Cd. Under Cd stress, all 237, 866 transcripts and 191, 370 unigenes were constructed in the transcriptome data of V. bonariensis roots. The enrichment analysis of gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway revealed that differentially expressed genes (DEGs) under Cd stress were predominately related to cell structure, reactive oxygen species (ROS) scavenging system, chelating reaction and secondary metabolites, transpiration and photosynthesis. DEGs encoding lignin synthesis, chalcone synthase (CHS) and anthocyanidin synthase (ANS) were prominent in V. bonariensis under Cd stress. The expression patterns of 10 DEGs, validated by quantitative real-time polymerase chain reaction (qRT-PCR), were in highly accordance with the RNA-Sequence (RNA-Seq) results. The novel strategies brought by our study was not only benefit for further studies on the tolerance of Cd and functional genomics in V. bonariensis, but also for the improvement molecular breeding and phytoremediation.

16.
Mol Psychiatry ; 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772302

RESUMO

Social interaction and communication are evolutionary conserved behaviours that are developed in mammals to establish partner cognition. Deficit in sociability has been represented in human patients and animal models of neurodevelopmental disorders, which are connected with genetic variants of synaptic glutamate receptors and associated PDZ-binding proteins. However, it remains elusive how these key proteins are specialized in the cellular level for the initial social behaviour during postnatal developmental stage. Here we identify a hippocampal CA3 specifically expressed PDZ scaffold protein Lnx1 required for initial social behaviour. Through gene targeting we find that Lnx1 deficiency led to a hippocampal subregional disorder in neuronal activity and social memory impairments for partner discrimination observed in juvenile mice which also show cognitive defects in adult stage. We further demonstrate that Lnx1 deletion causes NMDA receptor (NMDAR) hypofunction and this is attributable to decreased GluN2B expression in PSD compartment and disruption of the Lnx1-NMDAR-EphB2 complex. Specific restoration of Lnx1 or EphB2 protein in the CA3 area of Lnx1-/- mice rescues the defective synaptic function and social memory. These findings thus reveal crucial roles of postsynaptic NMDAR multiprotein complex that regulates the formation of initial social memory during the adolescent period.

17.
Nanoscale ; 11(47): 22734-22742, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31763653

RESUMO

Hydrogen production by water electrolysis is a common strategy for the development of renewable energy. However, meeting the industrial requirement for high efficiency and low cost is difficult to achieve with the existing methods. Herein, a novel and simple synthesis route for a dendritic self-supported electrode consisting of oxygen vacancy-rich NiO embedded within ultrathin 2D/3D nanostructures (NiO-Vo@2D/3D NS@DSE) for overall water splitting is developed for the first time. Based on the simple compound synthesis by jet electrodeposition and in situ acid etching, 2D nanosheets adhering uniformly to 3D nanospheres are successfully obtained on the dendritic self-supported skeleton surface. The experiments and density functional calculations illustrate that this electrode integrates the advantages including numerous active sites, intrinsic catalytic activity, good electrical conductivity, and outstanding reaction kinetic performance. Moreover, NiO-Vo@2D/3D NS@DSE shows excellent oxygen evolution reaction and hydrogen evolution reaction activities in 1 M KOH with overpotentials of 230 and 51 mV at 10 mA cm-2, respectively. Additionally, the electrode, as an alkali-electrolyzer, displays a potential of 1.51 V at 10 mA cm-2 with favorable stability that is superior to that of IrO2@nickel foam (NF)//Pt/C@NF (1.62 V). Surprisingly, the cost of NiO-Vo@2D/3D NS@DSE is ≈1/120 of the price of noble electrocatalysts with the same mass. This research opens up a new pathway for the design of bifunctional electrocatalysts.

18.
J Zhejiang Univ Sci B ; 20(11): 868-876, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31595723

RESUMO

Acrolein, known as one of the most common reactive carbonyl species, is a toxic small molecule affecting human health in daily life. This study is focused on the scavenging abilities and mechanism of ferulic acid and some other phenolic acids against acrolein. Among the 13 phenolic compounds investigated, ferulic acid was found to have the highest efficiency in scavenging acrolein under physiological conditions. Ferulic acid remained at (3.04±1.89)% and acrolein remained at (29.51±4.44)% after being incubated with each other for 24 h. The molecular mechanism of the detoxifying process was also studied. Detoxifying products, namely 2-methoxy-4-vinylphenol (product 21) and 5-(4-hydroxy-3-methoxyphenyl)pent-4-enal (product 22), were identified though nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS), after the scavenging process. Ferulic acid showed significant activity in scavenging acrolein under physiological conditions. This study indicates a new method for inhibiting damage from acrolein.


Assuntos
Acroleína/toxicidade , Ácidos Cumáricos/farmacologia , Acroleína/química , Ácidos Cumáricos/química , Glutationa/fisiologia , Hidroxibenzoatos/farmacologia , Espectroscopia de Ressonância Magnética , Relação Estrutura-Atividade
19.
Cyberpsychol Behav Soc Netw ; 22(10): 662-669, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31613156

RESUMO

Mobile gaming has gained popularity among adolescents, and an increase in problematic use has been reported. The aims of this study are as follows: (a) develop a self-report questionnaire, the Problematic Mobile Gaming Questionnaire (PMGQ); (b) establish a validated cutoff value using structured interviews; and (c) evaluate the prevalence of mobile gaming addiction in adolescents. The PMGQ was built as a 12-item questionnaire rated on a 4-point Likert scale to evaluate the symptoms of problematic mobile gaming (PMG). The construct validity of the PMGQ was examined using exploratory factor analysis. Overall, 10,775 students with smartphones from grade 4 to senior high school were recruited to complete the questionnaire. A total of 113 senior high school students were interviewed using previously developed criteria for PMG to develop an optimal cutoff point measuring sensitivity, specificity, and diagnostic accuracy. The cutoff point was determined using the Youden index and optimal diagnostic accuracy. The PMGQ showed good internal consistency (Cronbach's α = 0.92) and adequate diagnostic efficiency (area under the receiver operating characteristic curve = 0.802). The items revealed three factors of addiction: compulsion, tolerance, and withdrawal. For the PMGQ, a cutoff point of 29/30 demonstrated the most optimal Youden index and diagnostic accuracy. Demographic data showed that the proportion of PMG was 19.1 percent among elementary school students, 20.5 percent among junior high school students, and 19.0 percent among senior high school students. The PMGQ demonstrated appropriate validity and accuracy in the assessment for PMG.


Assuntos
Comportamento Aditivo/epidemiologia , Jogos de Vídeo/efeitos adversos , Adolescente , Humanos , Prevalência , Inquéritos e Questionários , Taiwan/epidemiologia
20.
Acta Crystallogr C Struct Chem ; 75(Pt 10): 1344-1352, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31589150

RESUMO

A novel modified polyoxometalate, {PMo12O40[Cu(2,2'-bpy)]}[Cu(2,2'-bpy)(en)(H2O)]2 [2,2'-bpy is 2,2'-bipyridyl (C10H8N2) and en is ethylenediamine (C2H8N2)], has been synthesized hydrothermally and structurally characterized by elemental analysis, TG, IR, XPS and single-crystal X-ray diffraction. The structural analysis reveals that the compound contains the reduced Keggin polyanion [PMo12O40]6- as the parent unit, which is monocapped by [Cu(2,2'-bpy)]2+ fragments via four bridging O atoms on an {Mo4O4} pit and bi-supported by two [Cu(2,2'-bpy)(en)(H2O)]2+ coordination cations simultaneously. There exist strong intramolecular π-π stacking between the capping and supporting units, which play a stabilizing role during the crystallization of the compound. Adjacent POM clusters are further aggregated to form a three-dimensional supramolecular network through noncovalent forces, hydrogen bonding and π-π stacking interactions. In addition, the photocatalytic properties were investigated in detail, and the results indicated that the compound can be used as a photocatalyst towards the decomposition of the organic pollutant methylene blue (MB).

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA