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1.
Polymers (Basel) ; 12(12)2020 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-33260485

RESUMO

Super-hydrophobic phenomena generally exist in nature, and wood can also obtain hydrophobicity by specific processing on the surface, being like the construction of microscale rough surface or decoration with low surface energy materials. In this research, the formation of hydrophobic layers on wood surface was investigated without breaking the wood's original structure. The core-shell structure particles were prepared by penetrating orthosilicate and polystyrene into the hollow mesoporous microsphere structure with tetrahydrofuran. A wood sample was coated with polydimethylsiloxane (PDMS) resin layer to enhance the adhesion of nano and micron hollow mesoporous microsphere on its surface. According to the surface structure of super-hydrophobic subjects in nature, the nano and micron hollow mesoporous microsphere were sprayed with different ratios several times to form a hydrophobic surface. The water contact angle could reach 150°, revealing that the hydrophobic behavior of the nano and micron hollow mesoporous microsphere coating was achieved. The microstructures of wood samples were examined by the scanning electron microscopy, and the chemical functional groups were investigated by the Fourier transform infrared; both verified that the hydrophobic surface was successfully coated. The thermogravimetric examination revealed the improved thermal stability of the hydrophobic wood. The scratch test was used to measure the abrasion resistance of the nano and micron hollow mesoporous microsphere coatings on wood surface. It was suggested that the nano and micron hollow mesoporous microsphere coating was an effective method to fabricate extremely hydrophobic wood products.

2.
Ying Yong Sheng Tai Xue Bao ; 31(9): 3067-3074, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-33345508

RESUMO

Long-term herbicide application may facilitate the adaptive evolution of weed populations. With Echinochloa crus-galli var. crus-galli population A from a rice field used for the experiment of effectiveness of herbicide in Nanling County, Anhui Province, we conducted common garden experi-ments with seeds of population A and three control populations collected from normal rice fields. Compared with the three control populations, population A had significantly lower seed production for individual plant, but higher 1000-seed weight. Population A had faster in seedling growth, higher in number of reproductive tillers, shorter life span, lower in height and biomass of individual plant, as well as lower in sensitivity to herbicide penoxsulam. Individuals from population A survived from 2× label dose (60 g·hm-2) of penoxsulam treatment at the three- to four-leaf stage showed significantly reduction in plant height, biomass, and mature seed production (1066 seeds per plant), but no difference in heading period, number of reproductive tillers, number of seeds per raceme and 1000-seed weight. The short lifespan, heavy seeds, dwarf architecture, more reproductive tillers and penoxsulam resistance made E. crus-galli var. crus-galli population A extremely adapting to rice planting systems, which should be prevented to spread to normal rice fields.


Assuntos
Echinochloa , Herbicidas , Traços de História de Vida , Oryza , Herbicidas/farmacologia , Humanos , Sementes
3.
Infect Drug Resist ; 13: 4155-4166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244245

RESUMO

Objective: There is a paucity of published data to evaluate the efficacy and safety of imipenem (IPM) and piperacillin-tazobactam (PT) dosing regimens in the treatment of septic patients acquiring continuous renal replacement therapy (CRRT). Methods and Materials: Critically-ill patients were grouped into short-stay and long-stay intensive care unit (ICU) patients. Pathogens were isolated from bloodstream infections in these patients. Minimum inhibitory concentration (MIC) value was determined by agar dilution method. Population PK models were introduced in this study, and differences in the likelihood of achieving efficacious and toxic exposures of IPM and PT for critically-ill patients were assessed. Results: A total of 86 K. pneumoniae bloodstream infection associated isolates were collected, and the MIC50 and MIC90 for short-stay ICU patients were 0.5/4 mg/L and 32/128 mg/L, respectively. IMP 0.5g q8h reached 90% probability of target attainment (PTA) against isolates with MICs ≤2 mg/L and was recommended to empirically treat short-stay ICU patients during CRRT based on the target of 40% ƒT>MIC. However, based on a more aggressive target of 100% ƒT>MIC, all the simulated IMP regimens except for IMP 1g q6h failed to achieve >80% cumulative fraction of response (CFR) in such patients. Unfortunately, the risk of drug-related toxicity for IMP 1g q6h was relatively high (50-85%). For PT, even the regimen of 4/0.5g q6h failed to provide sufficient antimicrobial exposure in short-stay ICU patients acquiring CRRT. Conclusion: No dose adjustment was required for the conventional IMP and PT regimens in the critically-ill population acquiring CRRT. Empirical treatment of IMP 0.5g q8h/q6h, not for PT, may provide sufficient antimicrobial exposure for short-stay ICU patients during CRRT. PT should be used in the knowledge of MIC results.

4.
Adv Mater ; 32(46): e2005433, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33063406

RESUMO

Heterostructures exhibit considerable potential in the field of energy conversion due to their excellent interfacial charge states in tuning the electronic properties of different components to promote catalytic activity. However, the rational preparation of heterostructures with highly active heterosurfaces remains a challenge because of the difficulty in component tuning, morphology control, and active site determination. Herein, a novel heterostructure based on a combination of RuMo nanoalloys and hexagonal N-doped carbon nanosheets is designed and synthesized. In this protocol, metal-containing anions and layered double hydroxides are employed to control the components and morphology of heterostructures, respectively. Accordingly, the as-made RuMo-nanoalloys-embedded hexagonal porous carbon nanosheets are promising for the hydrogen evolution reaction (HER), resulting in an extremely small overpotential (18 mV), an ultralow Tafel slope (25 mV dec-1 ), and a high turnover frequency (3.57 H2 s-1 ) in alkaline media, outperforming current Ru-based electrocatalysts. First-principle calculations based on typical 2D N-doped carbon/RuMo nanoalloys heterostructures demonstrate that introducing N and Mo atoms into C and Ru lattices, respectively, triggers electron accumulation/depletion regions at the heterosurface and consequently reduces the energy barrier for the HER. This work presents a convenient method for rational fabrication of carbon-metal heterostructures for highly efficient electrocatalysis.

5.
Sci Adv ; 6(41)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33028517

RESUMO

Nanoporous membranes with two-dimensional materials such as graphene oxide have attracted attention in volatile organic compounds (VOCs) and H2 adsorption because of their unique molecular sieving properties and operational simplicity. However, agglomeration of graphene sheets and low efficiency remain challenging. Therefore, we designed hierarchical nanoporous membranes (HNMs), a class of nanocomposites combined with a carbon sphere and graphene oxide. Hierarchical carbon spheres, prepared following Murray's law using chemical activation incorporating microwave heating, act as spacers and adsorbents. Hierarchical carbon spheres preclude the agglomeration of graphene oxide, while graphene oxide sheets physically disperse, ensuring structural stability. The obtained HNMs contain micropores that are dominated by a combination of ultramicropores and mesopores, resulting in high VOCs/H2 adsorption capacity, up to 235 and 352 mg/g at 200 ppmv and 3.3 weight % (77 K and 1.2 bar), respectively. Our work substantially expands the potential for HNMs applications in the environmental and energy fields.

6.
Int J Syst Evol Microbiol ; 70(10): 5211-5216, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32816657

RESUMO

A Gram-stain-positive, endospore-forming, motile and rod-shaped bacterium, designated as strain DSL-17T, was isolated from a tidal sediment of the East China Sea and characterized phylogenetically and phenotypically. The strain could grow at 16-47 °C (optimum 37 °C), at pH 6.0-10.0 (optimum 6.0) and with 1-7% (w/v) NaCl (optimum 3 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain DSL-17T was related to members of the genus Metabacillus and shared the highest similarity with Metabacillus litoralis SW-211T (98.6 %), followed by Metabacillus halosaccharovorans E33T (97.9 %), Metabacillus crassostreae JSM 100118T (97.7 %), Metabacillus niabensis 4T19T (97.7 %) and Metabacillus malikii NCCP-662T (97.5 %). 16S rRNA gene sequence similarities between strain DSL-17T and other members of the genus Metabacillus were below 96.6 %. The sole respiratory quinone was MK-7. Strain DSL-17T had a cell-wall peptidoglycan based on meso-diaminopimelic acid. The polar lipids were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), three unidentified glycolipids and six unidentified lipids. The strain had iso-C15 : 0, anteiso-C15 : 0, iso-C14 : 0, C16 : 0 and iso-C16 : 0 as major fatty acids. The G+C content of the genomic DNA was 35.7 mol%. The combined genotypic and phenotypic data indicated that strain DSL-17T represents a novel species of the genus Metabacillus, for which the name Metabacillus sediminilitoris sp. nov. is proposed The type strain is DSL-17T (=MCCC 1K03777T=DSM 109843T).


Assuntos
Bacillaceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
7.
Polymers (Basel) ; 12(8)2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32781550

RESUMO

As a hydrophilic material, wood is difficult to utilize for external applications due to the variable weather conditions. In this study, an efficient, facile, and low-cost method was developed to enhance the hydrophobicity of wood. By applying the low-temperature chemical vapor deposition (CVD) technology, the polydimethylsiloxane-coated wood (PDMS@wood) with hydrophobic surface was fabricated employing dichlorodimethylsilane as the CVD chemical resource. The result of water contact angle (i.e., 157.3°) revealed the hydrophobic behavior of the PDMS@wood. The microstructures of the wood samples were observed by scanning electron microscopy and energy dispersive X-ray spectroscopy (EDS) analysis verified PDMS successfully coated on wood surfaces. The chemical functional groups of the PDMS@wood were investigated by Fourier transform infrared (FT-IR) and Raman spectra. The thermogravimetric results indicated the enhanced thermal stability of the wood after PDMS coating. In addition, the stability test of PDMS@wood indicated that the hydrophobicity properties of the PDMS@wood samples were preserved after long-time storage (e.g., 30 days). The scratch test was carried out to examine the abrasion resistance of the hydrophobic coatings on PDMS@wood surface. It was suggested that low-temperature CVD process could be a successful approach for fabricating hydrophobic wood.

8.
PLoS Negl Trop Dis ; 14(8): e0008574, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32853274

RESUMO

BACKGROUND: Shifts have occurred in the epidemiological characteristics of Japanese encephalitis (JE), extending from the molecular level to the population level. The aim of this study was to investigate the seroprevalence of JE neutralizing antibodies in healthy populations from different age groups in Zhejiang Province, and to conduct mosquito monitoring to evaluate the infection rate of Japanese encephalitis virus (JEV) among vectors, as well as the molecular characteristics of the E gene of isolated JEV strains. METHODOLOGY/PRINCIPAL FINDINGS: A total of 1190 sera samples were screened by a microseroneutralization test, including 429 infants (28d-11m) and 761 participants (2y-82y). For those under 1 year old, the geometric mean titers (GMTs) of the JE neutralizing antibody was 9.49 at birth and significantly declined as the age of month increased (r = -0.225, P<0.001). For those above 1-year old, seropositive proportions were higher in subjects aged 1-3 years old as well as ≥25 years old (65%-75%), and relatively lower in subjects aged between 4-25 years old (22%-55%). Four or more years after the 2nd dose of JEV-L (first dose administered at 8 months and the second at 2 years of age), the seropositive proportion decreased to 32.5%, and GMTs decreased to 8.08. A total of 87,201 mosquitoes were collected from livestock sheds in 6 surveillance sites during 2015-2018, from which 139 E gene sequences were successfully amplified. The annual infection rate according to bias-corrected maximum likelihood estimation of JEV in Culex tritaeniorhynchus was 1.56, 2.36, 5.65 and 1.77 per 1000, respectively. JEV strains isolated during 2015-2018 all belonged to Genotype I. The E gene of amplified 139 samples differed from the JEV-L vaccine strain at fourteen amino acid residues, including the eight key residues related to virulence and virus attenuation. No divergence was observed at the sites related to antigenicity. CONCLUSIONS/SIGNIFICANCE: Zhejiang Province was at a high risk of JE exposure due to relatively lower neutralizing antibody levels among the younger-aged population and higher infection rates of JEV in mosquitoes. Continuous, timely and full coverage of JE vaccination are essential, as well as the separation of human living areas and livestock shed areas. In addition, annual mosquito surveillance and periodic antibody level monitoring are important for providing evidence for improvement in JE vaccines and immunization schedules.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/virologia , Epidemiologia Molecular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Neutralizantes , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Culex/virologia , Culicidae/virologia , Vírus da Encefalite Japonesa (Espécie)/classificação , Vírus da Encefalite Japonesa (Espécie)/imunologia , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Genes Virais/genética , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Mosquitos Vetores/virologia , Estudos Soroepidemiológicos , Adulto Jovem
9.
Science ; 369(6499): 77-81, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32376603

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in an unprecedented public health crisis. Because of the novelty of the virus, there are currently no SARS-CoV-2-specific treatments or vaccines available. Therefore, rapid development of effective vaccines against SARS-CoV-2 are urgently needed. Here, we developed a pilot-scale production of PiCoVacc, a purified inactivated SARS-CoV-2 virus vaccine candidate, which induced SARS-CoV-2-specific neutralizing antibodies in mice, rats, and nonhuman primates. These antibodies neutralized 10 representative SARS-CoV-2 strains, suggesting a possible broader neutralizing ability against other strains. Three immunizations using two different doses, 3 or 6 micrograms per dose, provided partial or complete protection in macaques against SARS-CoV-2 challenge, respectively, without observable antibody-dependent enhancement of infection. These data support the clinical development and testing of PiCoVacc for use in humans.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/imunologia , Betacoronavirus/isolamento & purificação , Chlorocebus aethiops , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Relação Dose-Resposta Imunológica , Feminino , Imunogenicidade da Vacina , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Projetos Piloto , Pneumonia Viral/virologia , Ratos , Ratos Wistar , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Células Vero , Carga Viral , Vacinas Virais/administração & dosagem , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia
10.
Cancer Manag Res ; 12: 2697-2709, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425592

RESUMO

Purpose: Biliverdin reductase A (BLVRA) is a pleiotropic enzyme that converts biliverdin-IX-alpha into the antioxidant and anti-nitrosative compound, bilirubin-IX-alpha. It is related to various diseases, including cancer. It is overexpressed in many types of cancers and promotes cancer development and metastasis, but the effects of BLVRA in colorectal cancer have not been researched at present. This study was aimed to investigate the effects of biliverdin reductase A (BLVRA) in vivo and vitro experiments and its possible mechanism. Methods: The clinical samples of CRC patients and CRC cell lines HT-29 and SW620 were chosen to perform the experiments. ELISA and Immunohistochemistry (IHC) were applied to test the level of BLVRA in patients. HT-29 knockdown of BLVRA and SW620 overexpression of BLVRA was established by the lentiviral vector transfection. Reverse transcription-quantitative real-time polymerase chain reaction and Western blotting were performed to examine the expression of BLVRA. MTT was used to detect the proliferation of CRC cells. Flow cytometry was applied to assess the rate of apoptosis. Transwell assay was performed to examine the capacity of migration and invasion. Immunofluorescence staining was adopted to assess the expression of E-cadherin and vimentin. Western blotting was utilized to detect the expression of apoptosis-related proteins, EMT-related proteins and target proteins of Wnt/ß-catenin signaling pathway. Results: Analysis of the clinical samples revealed that BLVRA was overexpressed in CRC patients and implied poor prognosis. BLVRA overexpression in the in vitro studies revealed that it increased the potential of CRC cells for proliferation, migration and invasion; augmented EMT; and hindered apoptosis. In addition, BLVRA overexpression was found to upregulate positive target genes and downregulate negative target genes of the Wnt/ß-catenin signaling pathway, which implied that the biological effects of BLVRA in CRC were mediated by this pathway. In contrast, knockdown of BLVRA manifested the opposite effects. Conclusion: Our results suggested that BLVRA might be a promising prognostic marker and a potential therapeutic target in CRC.

11.
ACS Appl Mater Interfaces ; 12(14): 16387-16393, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32180392

RESUMO

Ternary organic solar cells (OSCs) provide a convenient and effective means to further improve the power conversion efficiency (PCE) of binary ones via composition control. However, the role of the third component remains to be explored in specific binary systems. Herein, we report ternary blend solar cells by adding the narrow-band-gap donor PCE10 as the mediator into the PBDB-T:IDTT-T binary blend system. The extended absorption, efficient fluorescence resonance energy transfer, enhanced charge dissociation, and induced tighter molecular packing of the ternary blend films enhance the photovoltaic properties of devices and deliver a champion PCE of 10.73% with an impressively high open-circuit voltage (VOC) of 1.03 V. Good miscibility and similar molecular packing behavior of the components guarantee the desired morphology in the ternary blend films, leading to solar cell devices with over 10% PCEs at a range of compositions. Our results suggest that ternary systems with properly aligned energy levels and overlapping absorption among the components hold great promises to further enhance the performance of corresponding binary ones.

12.
ACS Appl Mater Interfaces ; 12(16): 19054-19061, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32212629

RESUMO

Ordered interlayer stacking is intrinsic in two-dimensional covalent organic frameworks (2D COFs) and has strong implications on COF's optoelectronic properties. Reversible interlayer sliding, corresponding to shearing of 2D layers along their basal plane, is an appealing dynamic control of both structures and properties, yet it remains unexplored in the 2D COF field. Herein, we demonstrate that the reversible interlayer sliding can be realized in an imine-linked tetrathiafulvalene (TTF)-based COF TTF-DMTA. The solvent treatment induces crystalline phase changes between the proposed staircase-like sql net structure and a slightly slipped eclipsed sql net structure. The solvation-induced crystallinity changes correlate well with reversible spectroscopic and electrical conductivity changes as demonstrated in oriented COF thin films. In contrast, no reversible switching is observed in a related TTF-TA COF, which differs from TTF-DMTA in terms of the absence of methoxy groups on the phenylene linkers. This work represents the first 2D COF example of which eclipsed and staircase-like aggregated states are interchangeably accessed via interlayer sliding, an uncharted structural feature that may enable applications such as chemiresistive sensors.

14.
iScience ; 23(1): 100761, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31887660

RESUMO

Effective design of bifunctional catalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is important but remains challenging. Herein, we report a three-dimensional (3D) hierarchical structure composed of homogeneously distributed Ni-Fe-P nanoparticles embedded in N-doped carbons on nickel foams (denoted as Ni-Fe-P@NC/NF) as an excellent bifunctional catalyst. This catalyst was fabricated by an anion exchange method and a low-temperature phosphidation of nanotubular Prussian blue analogue (PBA). The Ni-Fe-P@NC/NF displayed exceptional catalytic activity toward both HER and OER and delivered an ultralow cell voltage of 1.47 V to obtain 10 mA cm-2 with extremely excellent durability for 100 h when assembled as a practical electrolyser. The extraordinary performance of Ni-Fe-P@NC/NF is attributed to the abundance of unsaturated active sites, the well-defined hierarchical porous structure, and the synergistic effect between multiple components. Our work will inspire more rational designs of highly active non-noble electrocatalysts for industrial energy applications.

15.
Molecules ; 26(1)2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33396762

RESUMO

Hyperpolarization is one of the approaches to enhance Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI) signal by increasing the population difference between the nuclear spin states. Imaging hyperpolarized solids opens up extensive possibilities, yet is challenging to perform. The highly populated state is normally not replenishable to the initial polarization level by spin-lattice relaxation, which regular MRI sequences rely on. This makes it necessary to carefully "budget" the polarization to optimize the image quality. In this paper, we present a theoretical framework to address such challenge under the assumption of either variable flip angles or a constant flip angle. In addition, we analyze the gradient arrangement to perform fast imaging to overcome intrinsic short decoherence in solids. Hyperpolarized diamonds imaging is demonstrated as a prototypical platform to test the theory.

16.
Materials (Basel) ; 13(1)2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31877792

RESUMO

In this study, the low-cost processing residue of Radiata pine (Pinus radiata D. Don) was used as the lone carbon source for synthesis of CQDs (Carbon quantum dots) with a QY (The quantum yield of the CQDs) of 1.60%. The CQDs were obtained by the hydrothermal method, and +a PVA-based biofilm was prepared by the fluidized drying method. The effects of CQDs and CNF (cellulose nanofibers) content on the morphology, optical, mechanical, water-resistance, and wettability properties of the PVA/CQDs and PVA/CNF/CQDs films are discussed. The results revealed that, when the excitation wavelength was increased from 340 to 390 nm, the emission peak became slightly red-shifted, which was induced by the condensation between CQDs and PVA. The PVA composite films showed an increase in fluorescence intensity with the addition of the CNF and CQDs to polymers. The chemical structure of prepared films was determined by the FTIR spectroscopy, and no new chemical bonds were formed. In addition, the UV transmittance was inversely proportional to the change of CQDs content, which indicated that CQDs improved the UV barrier properties of the films. Furthermore, embedding CQDs Nano-materials and CNF into the PVA matrix improved the mechanical behavior of the Nano-composite. Tensile modulus and strength at break increased significantly with increasing the concentration of CQDs Nano-materials inside the Nano-composite, which was due to the increased in the density of crosslinking behavior. With the increase of CQDs content (>1 mL), the water absorption and surface contact angle of the prepared films decreased gradually, and the water-resistance and surface wettability of the films were improved. Therefore, PVA/CNF/CQDs bio-nanocomposite films could be used to prepare anti-counterfeiting, high-transparency, and ultraviolet-resistant composites, which have potential applications in ecological packaging materials.

17.
Arch Virol ; 164(10): 2565-2571, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31321585

RESUMO

Enteroviruses (EVs) are the major cause of hand, foot, and mouth disease (HFMD) and herpangina in children. In this study, we conducted a molecular investigation of EVs in throat swab samples from children in Hangzhou, China with a diagnosis of HFMD or herpangina. EVs were detected using one-step real-time RT-PCR, and their serotypes were determined based on partial VP1 gene sequences. The molecular typing results revealed the presence of six different EV serotypes in HFMD cases, including coxsackievirus (CV) A16 (20/30, 66.7%), CVA4 (3/30, 10.0%), CVA6 (3/30, 10.0%), EVA71 (2/30, 6.7%), CVB4 (1/30, 3.3%), and CVB5 (1/30, 3.3%). Eleven different EV serotypes were detected in herpangina cases, among which CVA4 was the most frequently detected serotype (105/170, 61.8%), followed by CVA16 (30/170, 17.6%), CVB4 (9/170, 5.3%), CVA6 (6/170, 3.5%), CVB3 (5/170, 2.9%), CVA10 (3/170, 1.8%), EVA71 (4/170, 2.4%), Echo9 (3/170, 1.8%), CVA9 (2/170, 1.2%), CVB1 (3/170, 1.8%) and CVA5 (1/170, 0.6%). The nucleotide sequence identity of EV strains from the same subtype ranged from 80.7% to 100%, and most of the EVs were closely related to virus strains found in Australia and mainland China. In conclusion, CVA 16 and CVA 4 were the main serotypes causing HFMD and herpangina, respectively, in children in Hangzhou in 2016. Most of these EVs were closely related to virus strains from Australia and mainland China.


Assuntos
Enterovirus/classificação , Enterovirus/isolamento & purificação , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Herpangina/epidemiologia , Herpangina/virologia , Sorogrupo , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , China/epidemiologia , Enterovirus/genética , Enterovirus/imunologia , Feminino , Variação Genética , Humanos , Lactente , Masculino , Epidemiologia Molecular , Tipagem Molecular , Faringe/virologia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
18.
Emerg Infect Dis ; 25(8): 1589-1591, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31310205

RESUMO

We report a disease outbreak caused by chikungunya virus in Zhejiang Province, China, in August 2017. Phylogenic analysis indicated that this virus belonged to the Indian Ocean clade of the East/Central/South African genotype and was imported by a traveler returning from Bangladesh.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya , Surtos de Doenças , Bangladesh , Febre de Chikungunya/história , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , China/epidemiologia , Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/virologia , Genoma Viral , História do Século XXI , Humanos , Filogenia , Doença Relacionada a Viagens
19.
J Am Chem Soc ; 141(29): 11420-11424, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31276387

RESUMO

Hexagonal hexaminophenyl benzene, tetragonal tetrakis(4-aminophenyl) ethane, and trigonal 1,3,5-tris(p-formylphenyl)benzene were all joined together by imine linkages to yield a 2D porous covalent organic framework with unprecedented tth topology, termed COF-346. Unlike the 5 simple existing 2D topologies reported in COFs, COF-346 has 3 kinds of vertices and 2 kinds of edges and is constructed with linkers of 3 kinds of connectivity, and thus represents a higher degree of complexity in COF structures. The success in crystallizing COF-346 was based on precisely chosen geometry and metrics of the linkers and error correction offered by dynamic imine formation. We also report two additional related COFs: a crystalline, porous COF, termed COF-360 with a rare kgd topology, as well as the first crystalline, porous COF with defected tth topology, termed COF-340.

20.
Respir Res ; 20(1): 126, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208426

RESUMO

BACKGROUND: Viral respiratory infection (VRI) is a common contraindication to elective surgery. Asymptomatic shedding among pediatric surgery patients (PSPs) could potentially lead to progression of symptomatic diseases and cause outbreaks of respiratory diseases. The aim of this study is to investigate the incidence of infection among mild symptomatic PSP group and asymptomatic PSP group after surgical procedure. METHODS: We collected the induced sputum from enrolled 1629 children (under 18 years of age) with no respiratory symptom prior to pediatric surgery between March 2017 and February 2019. We tested 16 different respiratory virus infections in post-surgery mild symptomatic PSP group and asymptomatic PSP group using a quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) assay panel. We analyzed symptom data and quantitative viral load to investigate the association between viruses, symptoms and viral quantity in qRT-PCR-positive PSPs. RESULTS: Out of 1629 children enrolled, a total of 204 respiratory viruses were present in 171 (10.50%) PSPs including 47 patients with mild symptoms and 124 with no symptoms after surgery. Commonly detected viruses were human rhino/enterovirus (HRV/EV, 42.19%), parainfluenza virus 3 (PIV3, 24.48%), coronavirus (CoV NL63, OC43, HKU1, 11.46%), and respiratory syncytial virus (RSV, 9.9%). PIV3 infection with a higher viral load was frequently found in PSPs presenting with mild symptoms, progressing to pneumonia with radiographic evidence after surgery. HRV/EV were the most commonly detected pathogens in both asymptomatic and mild symptomatic PSPs. CoV (OC43, HKU1) infections with a higher viral load were mostly observed in asymptomatic PSPs progressing to alveolar or interstitial infiltration. CONCLUSIONS: Our study suggested that PIV3 is a new risk factor for VRI in PSPs. Employing a more comprehensive, sensitive and quantitative method should be considered for preoperative testing of respiratory viruses in order to guide optimal surgical timing.


Assuntos
Infecções Respiratórias/diagnóstico , Infecções Respiratórias/cirurgia , Escarro/virologia , Viroses/diagnóstico , Viroses/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Infecções Respiratórias/epidemiologia , Estudos Retrospectivos , Viroses/epidemiologia
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