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1.
Dev Comp Immunol ; 103: 103501, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31634519

RESUMO

Tumor necrosis factor receptor-associated factor 6 (TRAF6), an E3 ubiquitin ligase, participates in both innate and adaptive immunity and regulates the apoptotic process. In this study, we observed that an ortholog of TRAF6 could inhibit the activity of p53 and suppress the apoptotic process in the Hong Kong oyster, Crassostrea hongkongensis. To investigate the possible molecular mechanism of the ChTRAF6-induced antiapoptotic effect, a GST pull-down screening assay was conducted, and ChPellino was found to physically interact with ChTRAF6. In addition, the interaction between them was confirmed by Co-immunoprecipitation. Furthermore, western blotting revealed that the phosphorylation level of ChPellino was decreased after the RNAi of ChTRAF6, demonstrating that ChTRAF6 may be an upstream regulator of Pellino activation. Furthermore, the apoptosis level of hemocytes increased after ChPellino knockdown, and ChPellino overexpression suppressed ChTRAF6-dependent p53 activation. Taken together, these results indicate that ChPellino plays a critical role in suppressing ChTRAF6-dependent anti-apoptosis in the hemocytes of Crassostrea hongkongensis.

2.
J Nanosci Nanotechnol ; 20(2): 1008-1012, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383098

RESUMO

Institute of Materials, Chinese Academy of Engineering Physics, Jiangyou 621908, P. R. China To improve the stability of organic-inorganic hybrid perovskite, cesium-containing methylammonium lead iodide perovskite have been synthesized by one-step solution deposition. With the increasing of Cs+ doping concentration, direct optical band gap of perovskite was increases, while defects and roughness of perovskite thin films were gradually augmented. A certain amount of Cs+ incorporated in perovskite absorb layer could improve power conversion efficiency through the enhancing of open circuit voltage and fill factor. However, excessive Cs+ doping concentration results in the reduced of short-circuit current and fill factor, which reduced power conversion efficiency. The optimized ratio 10% Cs+ doping achieved the highest power conversion efficiency (16.84%).

3.
Nanotechnology ; 31(2): 02LT01, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31550691

RESUMO

Self-catalyzed metal organic chemical vapor deposition (MOCVD) growth of Ga2O3 nanowires on GaN layers prepared on a sapphire substrate has been studied. Nanowire orientations are found to be growth temperature dominated. The vertical yields over total (VOT) curve shows a maximum peak beyond 70% around 480 °C, based on scanning electron microscope observations. X-ray diffraction patterns revealed a primary ß-(-201) normal orientation of as grown nanowires all over the studied temperature interval. Further transmission electron microscopy characterization had confirmed ß-(-201) normal axial orientation of these vertical nanowires, which have well crystallinity. The ß-(010)//GaN(110) in-plane epitaxial relationship is consistent with reported Ga2O3 film/nanowire growth. Nanowires crystallized in ß-[001] axial orientation were considered to be the inclined ones. Based on contrast experiments, the temperature dominated growth behavior is considered a thermodynamic process. The two observed crystalline orientation might have distinguishable but similar system energy, which results in coexistence of multi orientation nanowires over a large temperature span and an optimum temperature window for vertical ß-(-201) normal orientation. The presented optimized ß-Ga2O3 nanowire arrays with highest VOT close to 90% should effectively promote development of reliable high performance devices based on Ga2O3 nanowires.

4.
J Hazard Mater ; 382: 121090, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476718

RESUMO

Fenton reaction is widely used for hazardous pollutant degradation. Reducing agents (RAs) have been proven to be efficient in promoting the generation of HO• in Fenton reaction by accelerating the redox cycle of Fe3+/Fe2+. However, the roles of different RAs in Fenton reaction remain unrevealed. In this work, the catalytic activity of three RAs, i.e., hydroxylamine (NH2OH), ascorbic acid (AA) and cysteine (Cys), on the degradation of benzoic acid (BA) and the hydroxyl radical formation in the Fenton-RAs system were investigated. Results show the catalytic performance of RAs in BA degradation by Fenton reaction followed an order of NH2OH > AA > Cys. Compared with the conventional Fenton system, the effective pH range in the Fenton-NH2OH system extended from 3.0 to 5.0, while the optimal pH in the Fenton-AA and Fenton-Cys systems ranged from 3.0 to 4.0. The Fenton-AA system exhibited a two-stage reaction toward BA degradation, which was different from the Fenton-NH2OH and Fenton-Cys systems. Furthermore, the dosing manner of AA was found to be a key factor governing its role in the Fenton-AA system. This observation suggests the different mechanisms behind the enhancement of the three RAs in Fenton system. Different from NH2OH and Cys, AA would inhibit the generation of HO•, especially at the fast stage of degradation process, where Fe3+ has not accumulated yet. In addition, the economic analysis using the electrical energy per order indicates Fenton-NH2OH system was economically feasible with the lowest energy input, compared to Fenton-AA and Fenton-Cys systems. These results are useful to better understand the roles of RAs in Fenton system, and also provide guidance about the selection and dosing manner of suitable RAs in the advanced oxidation processes.

5.
Sci Total Environ ; 698: 134298, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505343

RESUMO

Many studies have examined the acute toxicity of nanoparticles (NPs) towards model bacteria. In this study, we report the time-dependent effects of ZnO NPs on native, selected Zn-resistant and dominant bacteria in estuarine waters. An initial inhibition of bacterial growth followed by a recovery at 24 h was observed, and this rebound phenomenon was particularly notable when the raw water samples were treated with relatively high ZnO NP concentrations (1 and 10 mg/L).By comparing the groups treated with Zn2+, Zn2+ was shown to largely explain the acute cytotoxic effect of ZnO NPs on bacteria in raw waters. Furthermore, similar to the native bacteria, especially the dominant bacteria, the viability of Escherichia coli (E. coli) decreased with the increasing treatments time and the concentrations of ZnO NPs in water with different salinities. Moreover, the expression of Zn-resistance genes including zntA and zntR in E. coli suggested that the Zn-resistance system in E. coli can be activated to defend against the stress of Zn2+ released from ZnO NPs, and salinity may promote this process in estuarine aquatic systems. Thus, the effect of ZnO NPs on bacteria in estuarine water bodies is likely determined by the synergistic effect of environmental salinity and dissolved Zn ions. As such, our findings are of high relevance and importance for understanding the ecological disturbances caused by anthropogenic NPs in estuarine environments.

6.
J Nanosci Nanotechnol ; 20(6): 3568-3575, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748053

RESUMO

Ultrafine nanoporous copper (UNP Cu) with a characteristic pore size of about 12 nm and a ligament size of about 14 nm was fabricated from amorphous Mg65Cu25Y10 precursor alloys after dealloying in a 0.1 M H2SO4 solution modified by poly(vinyly alcohol) polymers with a molecular weight of 105000 g/mol (PVA-124). The suppression of the surface diffusion from PVA-124 reduced the size of the nanopores and ligaments to 20 nm when the concentration of the added PVA-124 exceeded 0.1 g L-1. When the concentration of the added PVA-124 exceeded 2 g L-1, PVA-124 triggered the polymerization process. The resultant polymer surface layer on the fcc Cu ligaments was shown to reduce the rate of selective dissolution. It was also shown that extending the immersion time resulted in a suppression of coarsening. The introduction of PVA-124 polymer into acids resulted in a higher viscosity of the dealloying solutions, particularly when the concentration of PVA-124 was higher than 1.0 g L-1. This viscosity was shown not only to reduced rate of diffusion of Cu adatoms in PVA-124 solutions, but also forced the accumulation of Cu adatoms to form small scale UNP Cu.

7.
Arch Insect Biochem Physiol ; 103(1): e21636, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31612557

RESUMO

As a member of the low-density lipoprotein receptor (LDLR) superfamily, vitellogenin (Vg) receptor (VgR) is responsible for the uptake of Vg into developing oocytes and is a potential target for pest control. Here, a full-length VgR complementary DNA (named as CsVgR) was isolated and characterized in the rice stem borer, Chilo suppressalis. The composite CsVgR gene contained an open reading frame of 5,484 bp encoding a protein of 1,827 amino acid residues. Structural analysis revealed that CsVgR contained two ligand-binding domains (LBDs) with four Class A (LDLRA ) repeats in LBD1 and seven in LBD2, which was structurally different from most non-Lepidopteran insect VgRs having five repeats in LBD1 and eight in LBD2. The developmental expression analysis showed that CsVgR messenger RNA expression was first detectable in 3-day-old pupae, sharply increased in newly emerged female adults, and reached a peak in 2-day-old female adults. Consistent with most other insects VgRs, CsVgR was exclusively expressed in the ovary. Notably, injection of dsCsVgR into late pupae resulted in fewer follicles in the ovarioles as well as reduced fecundity, suggesting a critical role of CsVgR in female reproduction. These results may contribute to the development of RNA interference-mediated disruption of reproduction as a control strategy of C. suppressalis.

8.
Chemosphere ; 240: 124979, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726597

RESUMO

Activation of peroxymonosulfate (PMS) and persulfate (PS) by Fe2+ is widely used for oxidizing organic pollutants. However, their application is limited by the slow conversion rate of Fe3+ to Fe2+ and the accumulation of Fe3+. Here, we introduce commercial molybdenum disulfide (MoS2) to promote the activation of PMS and PS by Fe2+, and explore the mechanism of this promotion using experimental and theoretical methods. The Fe2+/PMS/MoS2 and Fe2+/PS/MoS2 systems achieved faster rate of PMS and PS conversion and also higher degradation efficiency toward pollutants. About 94.7% and 87.6% of rhodamine B (RhB) could be degraded in Fe2+/PMS/MoS2 (54 µM Fe2+, 1 mM PMS) and Fe2+/PS/MoS2 (54 µM Fe2+, 0.25 mM PS) system, respectively. MoS2 addition simultaneously promoted the Fe3+/Fe2+ cycle, the PMS and PS conversion, and the RhB mineralization. As a co-catalyst, MoS2 exhibited excellent stability for eight successive cycles of use. The predominant oxidant was identified as SO4- in Fe2+/PMS/MoS2 and Fe2+/PS/MoS2 systems. Theoretical calculations and a kinetic model were employed to evaluate the catalytic performance of the systems. These novel findings indicate that the combination of a commercially available MoS2 catalyst with a low dosage of Fe2+ is a promising and effective approach for efficient activation of PMS and PS to produce SO4- and OH.

9.
J Cell Biochem ; 121(1): 443-457, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31231887

RESUMO

Accumulating findings reveal that long noncoding RNAs (lncRNAs) as crucial regulatory molecules serve vital functions in the progression of hepatocellular carcinoma (HCC). This study aims to investigate the biological roles and mechanisms of lncRNA HOXD cluster antisense RNA 1 (HOXD-AS1) in HCC cells based on transcriptome analysis. The Cancer Genome Atlas data analysis and experimental validation showed that HOXD-AS1 was increased in HCC tissues/cell lines and positively relevant to histologic grade. The subcellular localization results indicated HOXD-AS1 was dispersed both in the nucleus as well as the cytoplasm of HCC cells. In vitro loss-of-function experiments revealed that silencing of HOXD-AS1 could dramatically suppress the proliferation, migration, and invasion, and induce S or/and G2/M phase cell cycle arrest as well as apoptosis of Bel-7402 and MHCC97H cells accompanying the changes in expression levels of cyclin B1, cyclin D1, BCL-2, BAX, and MMP2. In vivo assay also showed that HOXD-AS1 silencing could markedly reduce xenograft tumor volume and weight of HCC cells. Transcriptome and bioinformatic analysis indicated that a total of 1103 genes were significantly altered by HOXD-AS1 silencing, of which 132 genes exhibited a significant correlation with HOXD-AS1 expression in HCC tissues. Gene Ontology (GO) enrichment analysis revealed differentially expressed genes were remarkably enriched in several cancer-related biological processes (cell proliferation, cell cycle, apoptosis, migration, angiogenesis, and hypoxic response). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that HOXD-AS1 has the potential to affect p53, tumor necrosis factor (TNF), mitogen-activated protein kinase (MAPK) pathway, and Western blot results further validated that HOXD-AS1 silencing could inhibit the MEK/ERK pathway in Bel-7402 cells. Collectively, HOXD-AS1, as an oncogenic lncRNA, might exert crucial functions in HCC progression and serve as a potential diagnostic biomarker and therapeutic target for HCC.

10.
J Med Virol ; 92(1): 96-106, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31469179

RESUMO

Epstein-Barr virus (EBV) infection is one of the causes of gastric cancer (GC). Besides, previous studies have demonstrated that EBV-encoded latent membrane protein 2A (LMP2A) influences the pathogenesis of EBV-associated gastric cancer (EBVaGC) through regulating several key pathways. In this study, the expression level of Smad2 was observed, which was reduced in EBVaGC cell lines, especially in the presence of LMP2A. Meanwhile, we found that LMP2A promoted the expression of miR-155-5p by activated nuclear factor-κB (NF-κB) signaling. After being treated with NF-κB inhibitor (BAY 11-7082), miR-155-5p sharply decreased. Western blot analysis proved that the overexpression of miR-155-5p could inhibit Smad2. Functional studies showed that the role of miR-155-5p might lead to good prognosis in EBV-positive GC through promoting cell apoptosis and cell cycle arrest, as well as inhibiting tumor proliferation. In addition, p-Smad2 protein was also reduced or induced by overexpression or knockdown, respectively, of miR-155-5p. Immunofluorescence analysis further indicated that LMP2A prevented p-Smad2 from transferring to the nucleus, which played a crucial role in transforming growth factor-ß (TGF-ß) signaling. In summary, our findings confirmed the relationship between LMP2A and Smad2 and provided a potential regulation of the TGF-ß pathway in EBVaGC.

11.
Dis Colon Rectum ; 63(1): 84-92, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31633600

RESUMO

BACKGROUND: There is increased focus on the value of surgical care. Postoperative complications decrease value, but it is unknown whether high-value hospitals spend less than low-value hospitals in cases without complications. Previous studies have not evaluated both expenditures and validated outcomes in the same patients, limiting the understanding of interactions between clinical performance, efficient utilization of services, and costliness of surgical episodes. OBJECTIVE: This study aimed to identify payment differences between low- and high-value hospitals in colectomy cases without adverse outcomes using a linked data set of multipayer claims and validated clinical outcomes. DESIGN: This is a retrospective observational cohort study. We assigned each hospital a value score (ratio of cases without adverse outcome to mean episode payment). We stratified hospitals into tertiles by value and used analysis of variance tests to compare payments between low- and high-value hospitals, first for all cases, and then cases without adverse outcome. SETTING: January 2012 to December 2016, this investigation used clinical registry data from 56 hospitals participating in the Michigan Surgical Quality Collaborative, linked with 30-day episode payments from the Michigan Value Collaborative. PATIENTS: A total of 2947 patients undergoing elective colectomy were selected. MAIN OUTCOME MEASURES: The primary outcome measured was risk-adjusted, price-standardized 30-day episode payments. RESULTS: The mean adjusted complication rate was 31% (±10.7%) at low-value hospitals and 14% (±4.6%) at high-value hospitals (p < 0.001). Low-value hospitals were paid $3807 (17%) more than high-value hospitals ($22,271 vs $18,464, p < 0.001). Among cases without adverse outcome, payments were still $2257 (11%) higher in low-value hospitals ($19,424 vs $17,167, p = 0.04). LIMITATIONS: This study focused on outcomes and did not consider processes of care as drivers of value. CONCLUSIONS: In elective colectomy, high-value hospitals achieve lower episode payments than low-value hospitals for cases without adverse outcome, indicating mechanisms for increasing value beyond reducing complications. Worthwhile targets to optimize value in elective colectomy may include enhanced recovery protocols or other interventions that increase efficiency in all phases of care. See Video Abstract at http://links.lww.com/DCR/B56. LOGRANDO LA COLECTOMÍA DE ALTO VALOR: PREVINIENDO COMPLICACIONES O MEJORANDO LA EFICIENCIA: Hay un mayor enfoque en el valor de la atención quirúrgica. Las complicaciones postoperatorias disminuyen el valor, pero se desconoce si en los casos sin complicaciones, los hospitales de alto valor gastan menos que los hospitales de bajo valor. Estudios anteriores no han evaluado ambos gastos y validado resultados en los mismos pacientes, limitando la comprensión de las interacciones entre el rendimiento clínico, utilización eficiente de los servicios y costos de los episodios quirúrgicos.Identificar las diferencias de pago entre los hospitales de alto y bajo valor, en casos de colectomía sin resultados adversos, utilizando un conjunto de datos vinculados de reclamos de pago múltiple y resultados clínicos validados.Estudio de cohorte observacional retrospectivo. Asignamos a cada hospital una puntuación de valor (proporción de casos sin resultado adverso al pago medio del episodio). Estratificamos los hospitales por valor en terciles y utilizamos el análisis de pruebas de varianza para comparar los pagos entre hospitales de bajo y alto valor, primero para todos los casos y luego casos sin resultados adversos.De enero del 2012 a diciembre del 2016, utilizando datos de registro clínico de 56 hospitales que participan en el Michigan Surgical Quality Collaborative, vinculado con pagos de episodios de 30 días, del Michigan Value Collaborative.Un total de 2947 pacientes con colectomía electiva.Pagos por episodio de 30 días, ajustados al riesgo y estandarizados por precio.La tasa media de complicación ajustada fue de 31% (±10.7%) en hospitales de bajo valor y 14% (±4.6%) en hospitales de alto valor (p < 0.001). A los hospitales de bajo valor se les pagó $3807 (17%) más que a los hospitales de alto valor ($22,271 frente a $18,464, p < 0.001). Entre los casos sin resultados adversos, los pagos fueron de $2257 (11%) más altos en hospitales de bajo valor ($19,424 vs $17,167, p = 0.04).Este estudio se centró en los resultados y no se consideraron a los procesos de atención, como impulsores de valor.En la colectomía electiva, los hospitales de alto valor logran pagos de episodios más bajos, que en los hospitales de bajo valor con casos sin resultados adversos, indicando mecanismos para aumentar el valor, más allá que la reducción de complicaciones. Objetivos valiosos para optimizar el valor de la colectomía electiva, pueden incluir mejoras en los protocolos de recuperación, así como otras intervenciones que aumenten la eficiencia en todas las fases de la atención. Vea el resumen del video en http://links.lww.com/DCR/B56.

12.
G3 (Bethesda) ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792005

RESUMO

Reduced numbers of carpal and tarsal bones (wrist and ankle joints) are extensively observed in the clade of Cetacea and Ruminantia (Cetruminantia). Homebox D11 (Hoxd11) is one of the important genes required for limb development in mammals. Mutations in Hoxd11 can lead to defects in particular bones of limbs, including carpus and tarsus. To test whether evolutionary changes in Hoxd11 underlie the loss of these bones in Cetruminantia, we sequenced and analyzed Hoxd11 coding sequences and compared them with other 5' HoxA and HoxD genes in a taxonomic coverage of Cetacea, Ruminantia and other mammalian relatives. Statistical tests on the Hoxd11 sequences found an accelerated evolution in the common ancestor of cetaceans and ruminants, which coincided with the reduction of carpal and tarsal bones in this clade. Five amino acid substitutions (G222S, G227A, G229S, A240T and G261V) and one amino acid deletion (G254Del) occurred in this lineage. In contrast, other 5' HoxA and HoxD genes do not show this same evolutionary pattern, but instead display a highly conserved pattern of evolution in this lineage. Accelerated evolution of Hoxd11, but not other 5' HoxA and HoxD genes, is probably related to the reduction of the carpal and tarsal bones in Cetruminantia. Moreover, we found two amino acid substitutions (G110S and D223N) in Hoxd11 that are unique to the lineage of Cetacea, which coincided with hindlimb loss in the common ancestor of cetaceans. Our results give molecular evidence of Hoxd11 adaptive evolution in cetaceans and ruminants, which could be correlated with limb morphological adaptation.

13.
J Gastrointest Surg ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792904

RESUMO

BACKGROUND: Although the Clavien-Dindo classification is well established in many fields of surgery, a conclusive severity grading system for liver surgery-specific complications has not yet been standardized. Post-hepatectomy liver Failure, Ascites, Bile leakage, Infection, and Bleeding were found to be the five most important components in an international survey. A score system with FABIB as the acronym was proposed by the authors to increase the feasibility of routine use. METHODS: The definition and grading of three components ("liver failure," "bile leakage," and "bleeding") were adopted from the International Study Group for Liver Surgery. The definition and grading for "ascites" as well as "infection" were proposed by the authors. The postoperative complications were documented prospectively. The data from 2012 to 2016 were reviewed and the correlations to other clinical parameters were analyzed retrospectively. RESULTS: Five hundred one consecutive liver resections were assessed. Two hundred twenty-four (44.7%) patients had at least one postoperative complication of the FABIB system. The FABIB score was found to correlate with the operation complexity (major vs minor liver resection, with or without biliodigestive anastomosis), underlying liver disease (normal liver parenchyma vs fibrosis vs cirrhotic liver), 90-day mortality (statistically significantly different within three predefined categories), and the length of hospital stay (the mean value increases proportionately to FABIB score). CONCLUSION: Using the FABIB reporting system, the five main complications after liver surgery can be documented in a standardized manner. Its clinical relevance might increase the feasibility and comparability of studies or trials in liver surgery.

14.
J Cell Biochem ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31793054

RESUMO

Multidrug resistance (MDR) has become the major cause of failure chemotherapy for leukemia and high mortality of leukemia. The study aimed to investigate whether the let-7f mediate the Adriamycin (ADR) resistance of leukemia, and to explore the potential molecular mechanism. Cell proliferation was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and the soft agar clone formation assay. Flow cytometry was performed to detected cell cycle and apoptosis. The targeted regulationship was analyzed by dual-luciferase assay. Real-time polymerase chain reaction and Western blot were used to measure the expressions of let-7f, ABCC5, ABCC10, cell cycle-related proteins, and apoptosis-related proteins. The xenograft mouse model was used to conduct the tumor formation assay in vivo. The results demonstrated that the expression of let-7f was lower in multidrug-resistant K562/A02 cell lines compared to that in K562, while ABCC5 and ABCC10 were upregulated. Overexpression of let-7f in K562/A02 cell lines downregulated the ABCC5 and ABCC10 expression, enhanced cell sensitivity to ADR, promoted cell apoptosis, and inhibited cell proliferation. let-7f was proved to negatively regulate ABCC5 and ABCC10. Tumor formation assay further determined that let-7f overexpression increased sensitivity to ADR. Taken together, the let-7f downregulation induced the ADR resistance of leukemia by upregulating ABCC5 and ABCC10 expression. Our study provided a novel perspective to study the mechanism of MDR and a new target for the reversal of MDR.

15.
Nanoscale ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31793595

RESUMO

Quantum dot arrays in the form of molecular nanoporous networks are renowned for modifying the electronic surface properties through quantum confinement. Here we show that, compared to the pristine surface state, the band bottom of the confined states can exhibit downward shifts accompanied by a lowering of the effective masses simultaneous to the appearance of tiny gaps at the Brillouin zone boundaries. We observed these effects by angle resolved photoemission for two self-assembled homothetic (scalable) Co-coordinated metal-organic networks. Complementary scanning tunneling spectroscopy measurements confirmed these findings. Electron plane wave expansion simulations and density functional theory calculations provide insight into the nature of this phenomenon, which we assign to metal-organic overlayer-substrate interactions in the form of adatom-substrate hybridization. To date, the absence of the experimental band structure resulting from single metal adatom coordinated nanoporous networks has precluded the observation of the significant surface state renormalization reported here, which we infer to be general for low interacting and well-defined adatom arrays.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31787230

RESUMO

Sleep deprivation (SD) has detrimental effects on the physiological function of the brain. However, the underlying mechanism remains elusive. In the present study, we investigated the expression of candidate plasticity-related gene 15 (cpg15), a neurotrophic gene, and its potential role in SD using a REM-SD mouse model. Immunofluorescent and Western blot analysis revealed that the expression of cpg15 protein decreased in the hippocampus, ventral group of the dorsal thalamus (VENT), and somatosensory area of cerebral cortex (SSP) after 24-72 h of REM-SD, and the oxidative stress in these brain regions was increased in parallel, as indicated by the ratio of glutathione (GSH) to its oxidative product (GSSG). Over-expression of cpg15 in thalamus, hippocampus, and cerebral cortex mediated by AAV reduced the oxidative stress in these regions, indicating that the decrease of cpg15 might be a cause that augments oxidative stress in the sleep deprived mouse brain. Collectively, the results imply that cpg15 may play a protective function in the SD-subjected mouse brain via an anti-oxidative function. To our knowledge, this is the first time to provide evidences in the role of cpg15 against SD-induced oxidative stress in the brain.

17.
J Affect Disord ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31787422

RESUMO

BACKGROUND: Major depressive disorder (MDD) is common among older adults. The epidemiology of MDD is greatly influenced by sociocultural and economic factors. This study examined the 1-month and lifetime prevalence of MDD and its socio-demographic correlates in older adults living in Hebei province, an agricultural area of China. METHODS: Multistage, stratified, random sampling was administered between April and August 2016. The diagnosis of MDD was established with the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSM-IV) Axis I Disorders. RESULTS: A total of 3911 participants were enrolled. The 1-month and lifetime prevalence of MDD in older adults was 2.0% (95%CI: 1.6-2.4%) and 3.4% (95%CI: 2.8-4.0%), respectively. Multivariable logistic regression analyses revealed that female gender [P < 0.001, adjusted odds ratio (aOR) = 2.6, 95%CI: 1.53-4.53], presence of comorbid major medical conditions (P < 0.001, aOR = 4.8, 95%CI: 2.17-10.39) and family history of psychiatric disorders (P = 0.013, aOR = 3.4, 95%CI: 1.30-8.96) were independently and significantly associated with higher odds of MDD. CONCLUSION: The prevalence of MDD in older adults in Hebei province, China, was lower than most findings in China and other countries. Nevertheless, continued surveillance of elderly depression in China along with the development of primary, secondary and tertiary preventative interventions for the elderly with MDD is indicated.

18.
Exp Neurol ; : 113139, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31794744

RESUMO

OBJECTIVE: Inflammasome contributes to ischemic brain injury by inducing pyroptosis and inflammation. The aim of this study is to unravel the mechanism of long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3)-mediated regulation of absent in melanoma 2 (AIM2) inflammasome during cerebral ischemia/reperfusion (I/R). METHODS: In vivo middle cerebral artery occlusion (MCAO) rat model and in vitro oxygen-glucose deprivation/reperfusion (OGD/R)-treated neurocytes model were generated. TTC, H&E staining and TUNEL were performed to assess the cerebral ischemic injury. LDH and MTT assays were used to detect cell viability and cytotoxicity. qRT-PCR was used to detect the expression levels of MEG3, miR-485 and AIM2. Immunohistochemistry (IHC) and immunofluorescence were conducted to detect the AIM2 expression. ELISA and Western blotting were performed to determine the secretion and protein levels of inflammasome signaling proteins. Dual luciferase reporter assay and Ago2-RIP were used to validate the direct interaction among MEG3, miR-485 and AIM2. RESULTS: In both MCAO rats and OGD/R-treated neurocytes, MEG3 and AIM2 were significantly up-regulated, whereas miR-485 was down-regulated. MCAO induces pyroptosis and release of IL-1ß and IL-18 in ischemia brain. MEG3 acted as a molecular sponge to suppress miR-485, and AIM2 was identified as a direct target of miR-485. Knockdown of MEG3 inhibited OGD/R-induced pyroptosis and inflammation, and lack of MEG3 inhibited caspase1 signaling and decreased the expression of AIM2, ASC, cleaved-caspase1 and GSDMD-N. While overexpression of MEG3 exerted opposite effects. CONCLUSION: MEG3/miR-485/AIM2 axis contributes to pyroptosis via activating caspase1 signaling during cerebral I/R, suggesting that this axis may be a potent therapeutic target in ischemic stroke.

19.
J Neurosci Methods ; : 108538, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31794776

RESUMO

BACKGROUND: Functional near-infrared spectroscopy (fNIRS) was used to investigate spontaneous hemodynamic fluctuations in the bilateral temporal cortices for typically developing (TD) children and children with autism spectrum disorder (ASD). NEW METHOD: This paper proposed an approach to estimate the global time-varying behavior of brain activity through the measurement on change in first-order statistical properties directly from fNIRS time series. Then, a deep learning model combining the long-short term memory (LSTM) and convolutional neural network (CNN) was constructed based on the integration strategy with improved bagging algorithm, with the purpose to explore the potential patterns of temporal variation for ASD identification. RESULTS: Based on the theory of stationarity, analysis on the global time-varying behavior of hemodynamic fluctuations in oxy-hemoglobin (HbO2) and deoxy-hemoglobin (Hb) demonstrated that children with ASD showed weaker internal logic, but stronger memory and persistence to random shocks than TD children. Differentiating between ASD and TD with the proposed deep learning approach resulted in high accurate classification with sensitivity of 97.1% and specificity of 94.3%. COMPARISON WITH EXISTING METHODS: Using fNIRS time series of Hb from single optical channel, we achieved a better classification accuracy of 95.7% that was about 8% higher than previous methods with similar data. CONCLUSIONS: The characterization on time-varying behavior of brain activity holds promise for better understanding the underlying causes to ASD. And the deployed deep learning framework with an integration manner has the potential for screening children with risk of ASD.

20.
Cells ; 8(12)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795159

RESUMO

The phytohormone jasmonic acid (JA) plays an important role in various plant developmental processes and environmental adaptations. The JA signaling pathway has been well-elucidated in the reference plant Arabidopsis thaliana. It starts with the perception of the active JA derivative, jasmonoyl-isoleucine (JA-Ile), by the F-box protein COI1 which is part of the E3-ligase SCFCOI1. Binding of JA-Ile enables the interaction between COI1 and JAZ repressor proteins. Subsequent degradation of JAZ proteins leads to the activation of transcription factors like e.g., MYC2. Here we demonstrate that the pathway can be reconstituted in transiently transformed protoplasts. Analysis of the stability of a JAZ1-fLuc fusion protein as a function of COI1 transiently expressed in coi1 protoplasts allows structure function analysis of both JAZs and COI1. Using this system, we found that conserved cysteines in COI1 influence steady state COI1 protein levels. Using a luciferase reporter gene under the control of the JAZ1 promoter enable to address those features of JAZ1 that are required for MYC2 repression. Interestingly, the conserved TIFY-motif previously described to interact with NINJA to recruit the corepressor TOPLESS is not necessary for repression. This result is in favor of the alternative repression mode that proposes a direct competition between repressive JAZs and promotive MEDIATOR25 at MYC2. Finally, using protoplasts from the aos coi1 double mutant, which is deficient in JA synthesis and perception, we provide a system that has the potential to study the activity of different COI1 variants in the presence of different ligands.

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