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1.
Nanoscale ; 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32232280

RESUMO

Despite the crystallization of inorganic salt is being technologically related to the fabrication of salt-templated materials, the two key steps, nucleation and crystal growth, still lack the kinetic control to enable precise design of salt scaffolds. Here, we study how the undercooling degree controls the construction of salt scaffolds by kinetically manipulating the nucleation and growth rates in a NaCl-F127-rhodanine system. An effective approach based on undercooling-directed NaCl crystallization is further proposed to tailor the morphology and structure of the carbon materials. Under different undercooling conditions (liquid nitrogen, -55 °C and -25 °C freezing), the salt scaffold can be tuned as spheroidal particles, ellipsoidal nanocrystal aggregates and cubic nanocrystals with round corners, respectively. Correspondingly, hollow carbon nanospheres, nanocavity-linked graphene networks (CGN) and graphene nanosheets (GNS) can be fabricated through a salt template method, respectively. The Li+ and Na+ storage mechanisms of 3D CGN and 2D GNS are discussed, focusing on the ion diffusion kinetics. The enhanced Li+ diffusion kinetics in the 3D interconnected network endows CGN with better rate performance than GNS as lithium-ion battery anode material, and Na+ adsorption dominates the Na+ storage in CGN as sodium-ion battery anode material. Our findings provide a general idea for the construction crystallization-induced architectures and offer valuable insights to achieve fast Li+/Na+ storage by boosting the ion diffusion kinetics.

2.
J Plant Physiol ; 246-247: 153142, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32112957

RESUMO

WRKY transcription factors have been suggested to play important roles in response and adaptation to drought stress. However, how sorghum WRKY transcription factors function in drought stress is still unclear. Here, we identify a WRKY transcription factor of sorghum, SbWRKY30, which is induced significantly by drought stress. SbWRKY30 is mainly expressed in sorghum taproot and leaf. SbWRKY30 has transcriptional activation activity and functions in the nucleus. Heterologous expression of SbWRKY30 confers tolerance to drought stress in Arabidopsis (Arabidopsis thaliana) and rice by affecting root architecture. In addition, SbWRKY30 transgenic Arabidopsis and rice plants have higher proline contents and SOD, POD, and CAT activities but lower MDA contents than wild-type plants after drought stress. As a homologous gene of the drought stress-responsive gene RD19 of Arabidopsis, SbRD19 overexpression in Arabidopsis improved the drought tolerance of plants relative to wild-type plants. Further analysis demonstrated that SbWRKY30 could induce SbRD19 expression through binding to the W-box element in the promoter of SbRD19. These results suggest that SbWRKY30 functions as a positive regulator in response to drought stress. Therefore, SbWRKY30 may serve as a promising candidate gene for molecular breeding to generate drought-tolerant crops.

3.
Cancer Lett ; 474: 94-105, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31954771

RESUMO

Nuclear factor erythroid-2-related factor 2 (Nrf2), a transcription factor, participates in protecting cells from electrophilic or oxidative stresses through regulating expression of cytoprotective and antioxidant genes. It has become one of the emerging targets for cancer chemosensitization, and small molecule inhibitors of Nrf2 can enhance the efficacy of chemotherapeutic drugs. Here, we found that flumethasone, a glucocorticoid, inhibited Nrf2 signaling in A549 and H460 cells by promoting Nrf2 protein degradation. Moreover, flumethasone significantly increased the sensitivity of A549 and H460 cells to chemotherapeutic drugs including cisplatin, doxorubicin and 5-FU. In mice bearing A549-shControl cells-derived xenografts, the size and weight of xenografts in the flumethasone and cisplatin combination group had a significant reduction compared with those in the cisplatin group, while in mice bearing A549-shNrf2 cells-derived xenografts, the size and weight of the xenografts in the combination group had no significant difference compared with those in the cisplatin group, demonstrating that chemosensitization effect of flumethasone is Nrf2-dependent. This work suggests that flumethasone can potentially be used as an adjuvant sensitizer to enhance the efficacy of chemotherapeutic drugs in lung cancer.

4.
ACS Appl Mater Interfaces ; 12(4): 4821-4832, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31903756

RESUMO

Stimuli-responsive microcapsules, which can release the encapsulated payload under various environmental stimuli, have attracted great interests of the food, pharmaceutical, cosmetics, and agricultural fields in recent years. However, most reported responsive microcapsules normally have a single storage area and thus load/release only one type of payload under one stimulus. In this work, we fabricated a novel kind of multicompartmental intelligent microcapsule with two storage areas and independently controlled (preprogrammable) releasing behavior under different stimuli via rapid photopolymerization of Pickering emulsions. In our strategy, a temperature-sensitive polymeric (N-isopropyl acrylamide, pNIPAM) particle was prepared and loaded with Nile Red (NR), which was then employed as a Pickering emulsifier to stabilize oil-in-water droplets. The oil was composed of pH-responsive monomers and oil-soluble fluorescent green (OG). Upon exposure to photoirradiation, pH-responsive monomers were polymerized along the interior of the droplets and converted into microcapsules. With NR in the temperature-sensitive pNIPAM@NR particles and OG in the interior of the microcapsules, the as-prepared microcapsules possess dual-carrier capability with two payloads encapsulated dependently in two different compartments. In addition, the microcapsules could respond to two different external stimuli (temperature and pH) and realize the selective and independent release of encapsulated molecules (NR and OG) from the shell and core without any mutual interference. More importantly, the release of NR and OG can be programmed by preprogramming the order of the stimulus responses, which can be altered. Our work develops a simple and effective strategy to fabricate responsive multicompartment microcapsules with preprogrammable release of different molecules.

5.
Nucleic Acids Res ; 48(4): 1715-1729, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-31912146

RESUMO

N6-methyladenosine (m6A) is a reversible and dynamic RNA modification in eukaryotes. However, how cells establish cell-specific m6A methylomes is still poorly understood. Here, we developed a computational framework to systematically identify cell-specific trans regulators of m6A through integrating gene expressions, binding targets and binding motifs of large number of RNA binding proteins (RBPs) with a co-methylation network constructed using large-scale m6A methylomes across diverse cell states. We applied the framework and successfully identified 32 high-confidence m6A regulators that modulated the variable m6A sites away from stop codons in a cell-specific manner. To validate them, we knocked down three regulators respectively and found two of them (TRA2A and CAPRIN1) selectively promoted the methylations of the m6A sites co-localized with their binding targets on RNAs through physical interactions with the m6A writers. Knockdown of TRA2A increased the stabilities of the RNAs with TRA2A bound near the m6A sites and decreased the viability of cells. The successful identification of m6A regulators demonstrates a powerful and widely applicable strategy to elucidate the cell-specific m6A regulators. Additionally, our discovery of pervasive trans-acting regulating of m6A provides novel insights into the mechanisms by which spatial and temporal dynamics of m6A methylomes are established.


Assuntos
Adenosina/análogos & derivados , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a RNA/genética , RNA/genética , Adenosina/química , Adenosina/genética , Linhagem da Célula/genética , Sobrevivência Celular/genética , Regulação da Expressão Gênica/genética , Técnicas de Silenciamento de Genes/métodos , Células Hep G2 , Humanos , Metilação , Processamento Pós-Transcricional do RNA/genética
6.
Redox Biol ; 29: 101390, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31785531

RESUMO

The human HEAT repeat-containing protein 1 (HEATR1), consisting of 2144 amino acids, is a member of the UTP10 family and contains one HEAT repeat at its C-terminal. HEATR1 has been reported to regulate cytotoxic T lymphocytes and rRNA synthesis, while its functions in tumors are poorly understood. Here, we found that HEATR1 competed with Keap1 for binding to p62/sequestosome 1 (SQSTM1), resulted in up-regulation of Keap1, which then inhibited Nrf2 signaling in pancreatic cancer cells. HEATR1 knockdown enhanced proliferation and gemcitabine resistance of pancreatic cancer cells. Moreover, HEATR1 deficiency significantly improved xenografts growth and led to gemcitabine resistance in pancreatic cancer cell-derived xenografts through up-regulating Nrf2 signaling. By analyzing tumor tissue samples from pancreatic cancer patients, we found that low expression of HEATR1 was closely correlated with poor prognosis and clinicopathological features. Collectively, we suggest that HEATR1 deficiency promotes proliferation and gemcitabine resistance of pancreatic cancer through up-regulating Nrf2 signaling, indicating that HEATR1 may be a promising therapeutic target for pancreatic cancer.

7.
Chem Commun (Camb) ; 56(6): 904-907, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31850401

RESUMO

Single-ion copper doping significantly improves the catalytic activity of α-MnO2 in CO oxidation, reducing the apparent activation energy to ∼0.3 eV via strong electronic interactions between the frontier orbitals of copper ions and manganese ions.

8.
J Exp Clin Cancer Res ; 38(1): 371, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438982

RESUMO

BACKGROUND: Arachidonic acid (AA) metabolic enzymes including cyclooxygenase-2 (COX-2), microsomal prostaglandin E synthase-1 (mPGES-1) and cytochrome P450 (CYP) 4A11 play important roles in glioma angiogenesis. Thus, there is an urgent need to identify the underlying mechanisms and develop strategies to overcome them. METHODS: A homology model of human CYP4A11 was constructed using SYBYL-X 2.0. Structure-based virtual screening against COX-2, mPGES-1 and CYP4A11was performed using the Surflex-Dock of the SYBYL suite. The candidates were further evaluated their antiangiogenic activities in a zebrafish embryo and rabbit corneal angiogenesis model. Laser doppler analysis was used to measure tumor perfusion. The expression of CD31 and α-SMA was measured by immunofluorescence. Western blot was used to measure the expression of HIF-1, Akt and p-Akt. The gene expression of FGF-2, G-CSF, PDGF, TGF-ß, Tie-2, VEGF, lncRNA NEAT1 and miR-194-5p were determined using qPCR. The production of FGF-2, TGF-ß and VEGF were analyzed using ELISA. Bioinformatic analysis and luciferase reporter assays confirmed the interaction between lncRNA NEAT1 and miR-194-5p. RESULTS: The nearly 36,043 compounds from the Traditional Chinese Medicine (TCM) database were screened against COX-2, mPGES-1 and CYP4A11 3D models, and the 17 top flavonoids were identified. In zebrafish screening, isoliquiritigenin (ISL) exhibited the most potent antiangiogenic activities with the EC50 values of 5.9 µM. Conversely, the antiangiogenic effects of ISL in the zebrafish and rabbit corneal models were partly reversed by 20-hydroxyeicosatetraenoic acid (20-HETE) or prostaglandin E2 (PGE2). ISL normalized glioma vasculature and improved the efficacy of temozolomide therapy in the rat C6 glioma model. Inhibition of COX-2, mPGES-1 and CYP4A by ISL decreased FGF-2, TGF-ß and VEGF production in the C6 and U87 glioma cells with p-Akt downregulation, which was reversed by Akt overexpression. Furthermore, ISL downregulated lncRNA NEAT1 but upregulated miR-194-5p in the U87 glioma cell. Importantly, lncRNA NEAT1 overexpression reversed ISL-mediated increase in miR-194-5p expression, and thereby attenuated FGF-2, TGF-ß and VEGF production. CONCLUSIONS: Reprogramming COX-2, mPGES-1 and CYP4A mediated-AA metabolism in glioma by flavonoid ISL inhibits the angiogenic Akt- FGF-2/TGF-ß/VEGF signaling through ceRNA effect of miR-194-5p and lncRNA NEAT1, and may serve as a novel therapeutic strategy for human glioma.


Assuntos
Chalconas/farmacologia , Ciclo-Oxigenase 2/química , Citocromo P-450 CYP4A/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Prostaglandina-E Sintases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Neovascularização da Córnea/tratamento farmacológico , Neovascularização da Córnea/metabolismo , Neovascularização da Córnea/patologia , Ciclo-Oxigenase 2/metabolismo , Citocromo P-450 CYP4A/metabolismo , Inibidores Enzimáticos/farmacologia , Glioma/irrigação sanguínea , Glioma/metabolismo , Glioma/patologia , Humanos , Masculino , MicroRNAs/genética , Prostaglandina-E Sintases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/genética , Coelhos , Ratos , Ratos Wistar , Células Tumorais Cultivadas , Peixe-Zebra
9.
Chem Commun (Camb) ; 55(66): 9853-9856, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31364672

RESUMO

A rationale for designing selective NO reduction catalysts with strong alkali resistance was proposed, based on extensive studies of a variety of catalysts with common characteristics of separate catalytically active sites and alkali-trapping sites.

10.
World Neurosurg ; 129: e845-e850, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31212030

RESUMO

OBJECTIVE: Little is known about the effectiveness of lumbar drainage (LD) in the treatment of delayed or recurrent cerebrospinal fluid (CSF) leaks. We report our institutional experience and the effectiveness of LD in the management of delayed or recurrent CSF leaks. METHODS: Between January 2014 and December 2018, a total 21 patients with delayed or recurrent CSF leaks were enrolled in the research. All patients were treated conservatively for 48 hours, and LD was prescribed if CSF leaks still existed after 48 hours. If LD failed, endoscopic endonasal surgery (EES) was performed as soon as possible. Medical records were collected to analyze the effectiveness of LD. RESULTS: Among 21 patients, 4 patients experienced resolution with conservative treatment, and 17 patients were treated by CSF diversion by LD. The total cure rate of LD was 9/17 (52.9%). The cure rate was not statistically significantly different (relative risk = 3.33; Fisher exact test P = 0.131) between the traumatic group (8/12, 66.7%) and the transsphenoidal surgery group (1/5, 20.0%). During the follow-up time, no recurrence of CSF leaks was observed. CONCLUSIONS: The cure rate of LD in delayed or recurrent CSF leaks was lower than that of initial treatment with LD. The cure rate in the traumatic group tended to be higher than that in the transsphenoidal surgery group. EES can be used as a remedial treatment for patients in whom LD has failed.


Assuntos
Vazamento de Líquido Cefalorraquidiano/terapia , Derivações do Líquido Cefalorraquidiano , Neuroendoscopia , Resultado do Tratamento , Conduta Expectante , Adolescente , Adulto , Idoso , Drenagem/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
11.
Small ; 15(13): e1900099, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30811830

RESUMO

Fast and highly efficient enrichment and separation of glycoproteins is essential in many biological applications, but the lack of materials with high capture capacity, fast, and efficient enrichment/separation makes it a challenge. Here, a temperature-responsive core cross-linked star (CCS) polymer with boronate affinity is reported for fast and efficient enriching and separating of glycoproteins from biological samples. The temperature-responsive CCS polymers containing boronic acid in its polymeric arms and poly(N-isopropyl acrylamide) in its cross-linked core are prepared using reversible addition-fragmentation chain transfer polymerization via an "arm-first" methodology. The soluble boronate polymeric arms of the CCS polymers provide a homogeneous reaction system and facilitate interactions between boronic acid and glycoproteins, which leads to a fast binding/desorption speed and high capture capacity. Maximum binding capacity of the prepared CCS polymer for horseradish peroxidase is determined to be 210 mg g-1 , which can be achieved within 20 min. More interestingly, the temperature-responsive CCS polymers exhibit rapid reversible thermal-induced volume phase transition by increasing the temperature from 15 to 30 °C, resulting in a facile and convenient sample collection and recovery for the target glycoproteins. Finally, the temperature-responsive CCS polymer is successfully applied to enrichment of low abundant glycoproteins.

12.
J Pharmacol Exp Ther ; 368(3): 401-413, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30591531

RESUMO

Checkpoint blockade therapy has been proven efficacious in lung cancer patients. However, primary/acquired resistance hampers its efficacy. Therefore, there is an urgent need to develop novel strategies to improve checkpoint blockade therapy. Here we tested whether dual inhibition of cyclooxygenase-2 (COX-2) and epidermal growth factor receptor (EGFR) by flavonoid melafolone improves program death 1 (PD-1) checkpoint blockade therapy through normalizing tumor vasculature and PD-1 ligand (PD-L1) downregulation. Virtual screening assay, cellular thermal shift assay, and enzyme inhibition assay identified melafolone as a potential inhibitor of COX-2 and EGFR. In Lewis lung carcinoma (LLC) and CMT167 models, dual inhibition of COX-2 and EGFR by melafolone promoted survival, tumor growth inhibition, and vascular normalization, and ameliorated CD8+ T-cell suppression, accompanied by the downregulation of transforming growth factor-ß (TGF-ß), vascular endothelial growth factor (VEGF), and PD-L1 in the tumor cells. Mechanistically, dual inhibition of COX-2 and EGFR in lung cancer cells by melafolone increased the migration of pericyte, decreased the proliferation and migration of endothelial cells, and enhanced the proliferation and effector function of CD8+ T cells through VEGF, TGF-ß, or PD-L1 downregulation and PI3K/AKT inactivation. Notably, melafolone improved PD-1 immunotherapy against LLC and CMT167 tumors. Together, dual inhibition of COX-2 and EGFR by melafolone improves checkpoint blockade therapy through vascular normalization and PD-L1 downregulation and, by affecting vessels and immune cells, may be a promising combination strategy for the treatment of human lung cancer.


Assuntos
Antígeno B7-H1/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Flavonoides/farmacologia , Neoplasias Pulmonares/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Células A549 , Animais , Antígeno B7-H1/antagonistas & inibidores , Carcinoma Pulmonar de Lewis , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Flavonoides/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/fisiologia , Estrutura Secundária de Proteína
13.
Environ Sci Technol ; 52(20): 11796-11802, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30235416

RESUMO

Low-temperature selective catalytic reduction of NO by NH3 (NH3-SCR) is a promising technology for controlling NO emission from various industrial boilers, but it remains challenging because unavoidable deposition of ammonium bisulfates (ABS) in the stack gases containing both SO2 and H2O inevitably results in deactivation of catalysts. Here we developed a stable low-temperature NH3-SCR catalyst by supporting Fe2O3 cubes on surfaces of MoO3 nanobelts with NH4+-intercalatable interlayers, which enables Fe2O3/MoO3 to spontaneously prevent ABS from depositing on the surfaces. Using in situ synchrotron X-ray diffraction, 1H magic angle spinning nuclear magnetic resonance, and temperature-programmed decomposition procedure, the results demonstrate that NH4+ of ABS was initially intercalated in the interlayers of MoO3, leading to a NH4+-HSO4- cation-anion separation by conquering their strong electrostatic interactions, and subsequently the separated NH4+ was consumed by taking part in low-temperature NH3-SCR. Meanwhile, the surface HSO4- separated from ABS oxidized the reduced catalyst during the NH3-SCR redox cycle, concomitant with release of SO2 gas, thereby resulting in decomposition of ABS. This work assists the design of stable low-temperature NH3-SCR catalysts with strong resistance against deposition of ABS.


Assuntos
Amônia , Óxido Nítrico , Sulfato de Amônio , Temperatura Baixa , Temperatura Ambiente
14.
Chem Commun (Camb) ; 54(72): 10140-10143, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30132004

RESUMO

Metal-support electronic interactions were investigated in CO oxidation by using a Pd/CeO2 model catalyst with well-defined interfaces, and electron transfer from Pd cubes to CeO2 nanorods through interfaces triggered CO oxidation at low temperature where standalone Pd and CeO2 are inert.

15.
Fish Shellfish Immunol ; 81: 304-308, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30030114

RESUMO

In bony fish, CD40 and CD154 are two very important costimulatory molecules involved in T and B cell cooperation in thymus-dependent antibody production. In the current study, we identified the cDNAs of CD40 and CD154 and analyzed their genomic structures in grass carp. Quantitative real-time PCR indicated that the CD40 and CD154 were mainly expressed in immune organs. After challenge with grass carp reovirus (GCRV), these two genes were up-regulated at 72 h in head kidney and spleen. Moreover, seven and five single nucleotide polymorphisms (SNPs) were identified in the CD40 and CD154 respectively. Statistical analysis indicated that three SNPs in the coding region of the CD40 were significantly associated with the resistance of grass carp against GCRV. These results indicated that CD40 and CD154 play important roles in the responses to GCRV in grass carp. The SNP markers in the CD40 associated with the resistance to GCRV may facilitate the disease-resistant breeding of grass carp.


Assuntos
Antígenos CD40/genética , Ligante de CD40/genética , Carpas/genética , Doenças dos Peixes/genética , Infecções por Reoviridae/genética , Animais , DNA Complementar/genética , Resistência à Doença/genética , Polimorfismo de Nucleotídeo Único , Infecções por Reoviridae/veterinária
16.
Phys Chem Chem Phys ; 20(24): 16437-16443, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29873366

RESUMO

High-performance electrode materials that can be easily prepared are imperative for obtaining highly efficient lithium-ion batteries (LIBs). In this study, graphene-wrapped CoNi-layered double hydroxide (LDH) microspheres were first fabricated and used as an anode material for LIBs. The composite electrode with a mass ratio of 2.5 : 1 (CoNi-LDH/graphene) showed a high reversible specific capacity of 1428.0 mA h g-1 at 0.05 A g-1, excellent rate performances (977.5, 670.8 and 328.1 mA h g-1 at 0.5, 2 and 10 A g-1, respectively) and long-cycling performance (75% retention at 10 A g-1 after 10 000 cycles). The excellent electrochemical performances could be due to the following reasons: CoNi-LDHs had high chemical reactivity, and the graphene shell improved the electrical conductivity of CoNi-LDHs, which facilitated charge transfer; the graphene shell also suppressed the volume expansion of metal hydroxides during charge-discharge cycling and enhanced the cycle stability of the electrode. More importantly, this is a significant study to directly use LDHs as a potential electrode for LIBs, which can promote applications of electro-active LDHs in energy storage and conversion fields.

17.
ACS Nano ; 12(4): 4019-4024, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29608847

RESUMO

Although nucleation and crystallization in solution-processed materials synthesis is a natural phenomenon, the morphology design of graphene nanosheets by controlling the dual crystallization has not been established. In this work, we systematically demonstrate how the dual crystallization of ice and potassium chloride induces the morphological variation of the freeze-dried scaffold from fractal structure toward stepped sheet-like structure. A denim-like graphene nanosheet (DGNS) has been fabricated by annealing the F127-coated stepped sheet-like scaffold in nitrogen. DGNS shows parallel and straight stripes with an average stripe spacing of 10 nm. When used as a lithium-ion battery anode, DGNS possesses a superhigh reversible capacity of 1020 mAh g-1 at the current density of 1 A g-1 after 600 cycles. This work reports the control of dual crystallization of ice and salt crystals and provides an efficient way to design the morphology of two-dimensional materials by adjusting the crystallization.

18.
Infect Genet Evol ; 58: 23-26, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29126995

RESUMO

With the expanding of marine and freshwater aquaculture, the outbreaks of aquatic animal diseases have increasingly become the major threats to the healthy development of aquaculture industries. Notably, viral infections lead to massive fish deaths and result in great economic loss every year across the world. Hence, it is meaningful to clarify the biodiversity, geographical distribution and host specificity of fish-associated viruses. In this study, viral sequences detected in fish samples were manually collected from public resources, along with the related metadata, such as sampling time, location, specimen type and fish species. Moreover, the information regarding the host fish, including aliases, diet type and geographic distribution were also integrated into a database (FVD). To date, FVD covers the information of 4860 fish-associated viruses belonging to 15 viral families, which were detected from 306 fish species in 57 countries. Meanwhile, sequence alignment, live data statistics and download function are available. Through the user-friendly interface, FVD provides a practical platform that would not only benefit virologists who want to disclose the spread of fish-associated viruses, but also zoologists who focus on the health of domestic and wild animals. Furthermore, it may facilitate the surveillance and prevention of fish viral diseases. Database URL: http://bioinfo.ihb.ac.cn/fvd.


Assuntos
Bases de Dados Factuais , Doenças dos Peixes/virologia , Peixes/virologia , Vírus/classificação , Vírus/genética , Animais , Biologia Computacional/métodos , Interface Usuário-Computador , Navegador
19.
Chemistry ; 24(3): 681-689, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29030889

RESUMO

Alkali-metal ions often act as promoters rather than active components due to their stable outermost electronic configurations and their inert properties in heterogeneous catalysis. Herein, inert alkali-metal ions, such as K+ and Rb+ , are activated by electron transfer from a Hollandite-type manganese oxide (HMO) support for HCHO oxidation. Results from synchrotron X-ray diffraction, absorption, and photoelectron spectroscopies demonstrate that the electronic density of states of single alkali-metal adatoms is much higher than that of K+ or Rb+ , because electrons transfer from manganese to the alkali-metal adatoms through bridging lattice oxygen atoms. Electron transfer originates from the interactions of alkali metal d-sp frontier orbitals with lattice oxygen sp3 orbitals occupied by lone-pair electrons. Reaction kinetics data of HCHO oxidation reveal that the high electronic density of states of single alkali-metal adatoms is favorable for the activation of molecular oxygen. Mn L3 -edge and O K-edge soft-X-ray absorption spectra demonstrate that lattice oxygen partially gains electrons from the Mn eg orbitals, which leads to the upshift in energy of lattice oxygen orbitals. Therefore, the facile activation of molecular oxygen by the electron-abundant alkali-metal adatoms and active lattice oxygen are responsible for the high catalytic activity in complete oxidation of HCHO. This work could assist the design of efficient and cheap catalysts by tuning the electronic states of active components.

20.
Food Chem ; 239: 377-384, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28873582

RESUMO

The tyramine/glucose Maillard reaction was proposed as an emerging tool for tyramine reduction in a model system and two commercial soy sauce samples. The model system was composed of tyramine and glucose in buffer solutions with or without NaCl. The results showed that tyramine was reduced in the model system, and the reduction rate was affected by temperature, heating time, initial pH value, NaCl concentration, initial glucose concentration and initial tyramine concentration. Changes in fluorescence intensity and ultraviolet-visible (UV-vis) absorption spectra showed three stages of the Maillard reaction between tyramine and glucose. Cytotoxicity assay demonstrated that tyramine/glucose Maillard reaction products (MRPs) were significantly less toxic than that of tyramine (p<0.05). Moreover, tyramine concentration in soy sauce samples was significantly reduced when heated with the addition of glucose (p<0.05). Experimental results showed that the tyramine/glucose Maillard reaction is a promising method for tyramine reduction in foods.


Assuntos
Glucose/química , Tiramina/química , Reação de Maillard , Alimentos de Soja
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