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1.
Mikrochim Acta ; 191(7): 401, 2024 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884887

RESUMO

The simultaneous discrimination and detection of multiple anions in an aqueous solution has been a major challenge due to their structural similarity and low charge radii. In this study, we have constructed a supramolecular fluorescence sensor array based on three host-guest complexes to distinguish five anions (F-, Cl-, Br-, I-, and ClO-) in an aqueous solution using anionic-induced fluorescence quenching combined with linear discriminant analysis. Due to the different affinities of the three host-guest complexes for each anion the anion quenching efficiency for each host-guest complex was likewise different, and the five anions were well recognized. The fluorescence sensor array not only distinguished anions at different concentrations (0.5, 10, and 50 µM) with 100% accuracy but also showed good linearity within a certain concentration range. The limit of detection (LOD) was < 0.5 µM. Our interference study showed that the developed sensor array had good anti-interference ability. The practicability of the developed sensor array was also verified by the identification and differentiation of toothpaste brands with different fluoride content and the prediction of the iodine concentration in urine combined with machine learning.


Assuntos
Ânions , Iodo , Limite de Detecção , Aprendizado de Máquina , Espectrometria de Fluorescência , Ânions/urina , Ânions/química , Iodo/urina , Iodo/química , Espectrometria de Fluorescência/métodos , Cremes Dentais/química , Corantes Fluorescentes/química , Fluoretos/química , Fluoretos/urina , Análise Discriminante
2.
J Am Chem Soc ; 141(19): 7743-7750, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31017418

RESUMO

Although significant improvements have been achieved for organic photovoltaic cells (OPVs), the top-performing devices still show power conversion efficiencies far behind those of commercialized solar cells. One of the main reasons is the large driving force required for separating electron-hole pairs. Here, we demonstrate an efficiency of 14.7% in the single-junction OPV by using a new polymer donor PTO2 and a nonfullerene acceptor IT-4F. The device possesses an efficient charge generation at a low driving force. Ultrafast transient absorption measurements probe the formation of loosely bound charge pairs with extended lifetime that impedes the recombination of charge carriers in the blend. The theoretical studies reveal that the molecular electrostatic potential (ESP) between PTO2 and IT-4F is large, and the induced intermolecular electric field may assist the charge generation. The results suggest OPVs have the potential for further improvement by judicious modulation of ESP.


Assuntos
Fontes de Energia Elétrica , Compostos Orgânicos/química , Energia Solar , Eletricidade Estática , Transporte de Elétrons , Fulerenos/química , Modelos Moleculares , Conformação Molecular , Polímeros/química
3.
Macromol Rapid Commun ; 40(19): e1900246, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31298781

RESUMO

In polymer solar cells (PSCs), it is difficult for twisted conjugated polymers to achieve high power-conversion efficiency (PCE) as donors due to their low charge carrier mobilities and poor bulk heterojunction morphologies. In this work, a new twisted conjugated polymer (P3TCO-1) with excellent solubilities (above 30 mg mL-1 ) in common organic solvents at room temperature is reported. UV-visible absorption spectra and cyclic voltammetry indicate that P3TCO-1 has a wide optical bandgap of 1.90 eV and deep HOMO level of -5.39 eV. In binary PSCs, P3TCO-1:ITIC-based device shows a PCE of 10.11%, with JSC of 17.05 mA cm-2 and FF of 62.89%; P3TCO-1:PC71 BM-based device gives a PCE of 6.67% with JSC of 12.31 mA cm-2 and FF of 58.00%. When the two acceptors of ITIC and PC71 BM are combined, the twisted P3TCO-1-based ternary PSCs exhibit a significantly boosted PCE of up to 11.41%, with a simultaneously improved JSC of 18.16 mA cm-2 and FF of 66.78%. These results can guide the improvement of PCE for twisted conjugated polymer-based PSCs.


Assuntos
Ácidos Carboxílicos/química , Polímeros/química , Energia Solar , Tiofenos/química , Fontes de Energia Elétrica , Estrutura Molecular , Polímeros/síntese química , Teoria Quântica
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(6): 585-588, 2019 Jun.
Artigo em Zh | MEDLINE | ID: mdl-31208514

RESUMO

A female infant was admitted to the hospital due to perioral cyanosis two hours after birth. The infant was born at the gestational age of 35 weeks by cesarean section with a birth weight of 2 400 g. Physical examination revealed wry mouth to the left side while crying, small auricles, and high palatal arch; fibrolaryngoscopy suggested bilateral vocal cord paralysis; echocardiography suggested ventricular septal defect; single nucleotide polymorphism testing showed 22q11.21 microdeletion. Therefore, the infant was given a definite diagnosis of asymmetric crying facies syndrome accompanied by 22q11.21 microdeletion. After 8-month follow-up, the infant still had asymmetric crying facies with presence of growth retardation.


Assuntos
Paralisia Facial , Cardiopatias Congênitas , Paralisia das Pregas Vocais , Cesárea , Choro , Feminino , Humanos , Lactente , Gravidez
5.
Yao Xue Xue Bao ; 51(7): 1165-74, 2016 07.
Artigo em Zh | MEDLINE | ID: mdl-29897694

RESUMO

The content changes of chemical components in different phenological phase of the cultivated Polygala tenuifolia is one of the important factors for determination of the best harvest time in the production practice. In this study, the digital gene expression (DGE) profiles of the cultivated P. tenuifolia were analyzed in different phenological phase (flowering fruit bearing stage, wilting stage, dormancy stage). The differentially expressed genes were found in the biosynthesis of chemical composition in P. tenuifolia, and the representational ones were validated by RT-q PCR. Then, the key enzymes(CYP450s and UGTs) involved in the downstream of the triterpenoid saponins biosynthesis pathway in P. tenuifolia were predicted through the correlation analysis of gene expression. The number of down-regulated genes was more than that of up-regulated in P. tenuifolia from flowering fruit bearing stage to dormancy stage. Six differentially expressed genes (HMGS, PMK, FPPS, SQS, SE, ß-AS) and five (PAL, C4 H, 4CL, CAD, peroxidase) were annotated to the triterpenoid saponins and phenylpropanoid biosynthesis pathway in P. tenuifolia, respectively. Compared to wilting and dormancy stages, the saponins, xanthones, and lignins were largely synthesized at the flowering fruit bearing stage of P. tenuifolia. Furthermore, UGT83A1, CYP716B1, CYP98A3, CYP86B1, and CYP94A1 may be the part of key enzymes in the downstream of the triterpenoid saponins biosynthesis pathway in P. tenuifolia. This study provides evidence to support the correctness of traditional harvest time of P. tenuifolia at the level of transcription, and lays the scientific foundation for gene cloning and functional verification of CYP450 s and UGTs in the downstream of the triterpenoid saponins biosynthesis pathway in P. tenuifolia in the future.


Assuntos
Polygala/genética , Transcriptoma , Sistema Enzimático do Citocromo P-450/metabolismo , Flores , Frutas , Glucuronosiltransferase/metabolismo , Lignina/biossíntese , Dormência de Plantas , Saponinas/biossíntese , Triterpenos/metabolismo , Xantonas/metabolismo
6.
BMC Infect Dis ; 14: 506, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25231540

RESUMO

BACKGROUND: Changes of miRNAs in exosome have been reported in different disease diagnosis and provided as potential biomarkers. In this study, we compared microRNA profile in exosomes in 5 MHFMD and 5 ESHFMD as well as in 5 healthy children. METHODS: Different expression of miRNAs in exosomes across all the three groups were screened using miRNA microarray method. Further validated test was conducted through quantitative real-time PCR assays with 54 exosome samples (18 ESHFMD, 18 MHFMD, and 18 healthy control). The judgment accuracy was then estimated by the receiver operating characteristic (ROC) curve analysis; and the specificity and sensitivity were evaluated by the multiple logistic regression analysis. RESULTS: There were 11 different miRNAs in exosomes of MHFMD and ESHFMD compared to healthy children, of which 4 were up-regulated and 7 were down-regulated. Further validation indicated that the 4 significant differentially expressed candidate miRNAs (miR-671-5p, miR-16-5p, miR-150-3p, and miR-4281) in exosome showed the same changes as in the microarray analysis, and the expression level of three miRNAs (miR-671-5p, miR-16-5p, and miR-150-3p) were significantly different between MHFMD or ESHFMD and the healthy controls. The accuracy of the test results were high with the under curve (AUC) value range from 0.79 to 1.00. They also provided a specificity of 72%-100% and a sensitivity of 78%-100%, which possessed ability to discriminate ESHFMD from MHFMD with the AUC value of 0.76-0.82. CONCLUSIONS: This study indicated that the exosomal miRNA from patients with different condition of HFMD express unique miRNA profiles. Exosomal miRNA expression profiles may provide supplemental biomarkers for diagnosing and subtyping HFMD infections.


Assuntos
Exossomos/metabolismo , Doença de Mão, Pé e Boca/diagnóstico , MicroRNAs/genética , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Diagnóstico Diferencial , Exossomos/genética , Ontologia Genética , Doença de Mão, Pé e Boca/sangue , Doença de Mão, Pé e Boca/genética , Humanos , MicroRNAs/sangue , Anotação de Sequência Molecular , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Índice de Gravidade de Doença , Transcriptoma , Regulação para Cima
7.
J Mater Sci Mater Med ; 25(6): 1461-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24652594

RESUMO

Molecularly imprinted poly(hydroxyethyl methacrylate) microspheres (PHEMA MIPMs) were prepared via precipitation polymerization in this article, using gatifloxacin (GFLX), hydroxyethyl methacrylate (HEMA), and ethylene glycol dimethacrylate (EGDMA) as template molecule, functional monomer and cross-linker, respectively. The effects of reaction medium, initial total monomers, cross-linker and molecular imprinting on the polymerization were investigated systematically. The interaction between GFLX and HEMA in pre-solution was studied by UV-Visible spectrophotometer, both size and morphology of products were characterized by a scanning electron microscope. When the total initial monomer concentration was 1 vol%, EGDMA content was 70 mol%, a group of uniform PHEMA MIPMs were prepared at different GFLX/MAA molar ratios, with diameter range from 2.06 ± 0.07 to 2.82 ± 0.20 µm. The results of drug loading and in vitro release experiments demonstrated that PHEMA MIPMs could achieve a higher GFLX loading content and a more acceptable sustained release than non-imprinted ones.


Assuntos
Acrilatos/química , Cápsulas/síntese química , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Fluoroquinolonas/administração & dosagem , Fluoroquinolonas/química , Impressão Molecular/métodos , Polímeros/química , Antibacterianos/administração & dosagem , Antibacterianos/síntese química , Cápsulas/administração & dosagem , Difusão , Gatifloxacina , Teste de Materiais , Tamanho da Partícula , Propriedades de Superfície
8.
Artigo em Zh | MEDLINE | ID: mdl-25518595

RESUMO

OBJECTIVE: To research the morphological characteristics and differential gene expression of Chrysomya megacephala eggs in different developmental stages. METHODS: After C. megacephala laid eggs (0 h), the eggs were collected every 2 h until eggs hatched into larvae. The morphological characteristics of C. megacephala eggs in different developmental stages were observed by stereo microscopy and scanning electron microscopy. The total RNA of the fly eggs was extracted. The expression levels of bicoid, slalom and chitin synthase genes was determined by real-time flourescence quantitative PCR. Statistic analyses were performed with SPSS 19.0. RESULTS: Under the stereomicroscope, at 0-4 h after egg laying, the morphological change of C. megacephala eggs was not obvious. At the 6th hour after egg laying, somites were formed. After 8 hours the eggs shriveled. At the 9th hour after egg laying, the eggs hatched into larvae. The scanning electron microscope images showed that the morphological change of eggs was not obvious in the first 4 hours, the end of micropyle slightly outward, the surface around the micropyle was smooth. At the 6th hour after egg laying, the end of micropyle began to sag and irregular protrusions formed around the micropyle. At the 8th hour the end of micropyle was obviously dented. After 9 hours larvae hatched from eggs. Real-time fluorescence quantitative PCR indicated that the expression levels of bicoid, slalom and chitin synthase genes from C. megacephala eggs regularly changed with the developmental stages. There was a significant difference in threshold cycle values among the three genes (P<0.05). CONCLUSION: The morphological characteristics of C. megacephala eggs change with the development stage. The levels of gene expression in different development period of C. megacephala eggs are different.


Assuntos
Dípteros/crescimento & desenvolvimento , Dípteros/genética , Animais , Expressão Gênica , Larva , Microscopia Eletrônica de Varredura
9.
Virol J ; 10: 115, 2013 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-23577963

RESUMO

BACKGROUND: Hand, foot and mouth diseases (HFMD) caused by enterovirus 71(EV71) presents a broad spectrum of clinical manifestations ranging from mild febrile disease to fatal neurolocal disease. However, the mechanism of virulence is unknown. METHODS: We isolated 6 strains of EV71 from HFMD patients with or without neurological symptoms, and sequenced the whole genomes of the viruses to reveal the virulence factors of EV71. RESULTS: Phylogenetic tree based on VP1 region showed that all six strains clustered into C4a of C4 sub-genotype. In the complete polypeptide, 298 positions were found to be variable in all strains, and three of these positions (Val(P814)/Ile(P814) in VP1, Val(P1148)/Ile(P1148) in 3A and Ala(P1728)/Cys)/Val(P1728) in 3C) were conserved among the strains with neurovirulence, but variable in strains without neurovirulence. In the 5'-UTR region, it showed that the first 10 nucleotides were mostly conserved, however from the 11th nucleotide, nucleotide insertions and deletions were quite common. The secondary structure prediction of 5'-UTR sequences showed that two of three strains without neurovirulence (SDLY11 and SDLY48) were almost the same, and all strains with neurovirulence (SDLY96, SDLY107 and SDLY153) were different from each other. SDLY107 (a fatal strain) was found different from other strains on four positions (C(P241)/T(P241), A(P571)/T(P571), C(P579)/T(P579) in 5'-UTR and T(P7335)/C(P7335) in 3'-UTR). CONCLUSIONS: The three positions (Val(P814)/Ile(P814) in VP1, Val(P1148)/Ile(P1148) in 3A and Ala(P1728)/Cys(P1728)/Val(P1728) in 3C), were different between two phenotypes. These suggested that the three positions might be potential virulent positions. And the three varied positions were also found to be conserved in strains with neurovirulence, and variable in strains without neurovirulence. These might reveal that the conservation of two of the three positions or the three together were specific for the strains with neurovirulence. Varation of secondary structure of 5'-UTR, might be correlated to the changes of viral virulence. SDLY107 (a fatal strain) was found different from other strains on four positions, these positions might be related with death.


Assuntos
Enterovirus Humano A/genética , Genoma Viral , Doença de Mão, Pé e Boca/patologia , Doença de Mão, Pé e Boca/virologia , RNA Viral/genética , Análise de Sequência de DNA , Proteínas Virais/genética , Substituição de Aminoácidos , Análise por Conglomerados , Enterovirus Humano A/isolamento & purificação , Enterovirus Humano A/patogenicidade , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , Virulência
10.
BMC Infect Dis ; 13: 383, 2013 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-23961958

RESUMO

BACKGROUND: To clarify the molecular mechanisms that participate in the severe hand, foot and mouth disease (HFMD) infected by Enterovirus 71 and to detect any related protein biomarkers, we performed proteomic analysis of protein extracts from 5 extremely severe HFMD children and 5 healthy children. METHODS: The protein profiles of them were compared using two-dimensional electrophoresis. Differentially expressed proteins were identified using mass spectrometry. Functional classifications of these proteins were based on the PANTHER. The interaction network of the differentially expressed protein was generated with Pathway Studio. RESULTS: A total of 38 differentially expressed proteins were identified. Functional classifications of these proteins indicated a series of altered cellular processes as a consequence of the severe HFMD. These results provided not only new insights into the pathogenesis of severe HFMD, but also implications of potential therapeutic designs. CONCLUSIONS: Our results suggested the possible pathways that could be the potential targets for novel therapy: viral protection, complement system and peroxide elimination.


Assuntos
Enterovirus Humano A/isolamento & purificação , Doença de Mão, Pé e Boca/sangue , Proteoma/análise , Proteínas Sanguíneas/análise , Western Blotting , Eletroforese em Gel Bidimensional , Humanos , Mapas de Interação de Proteínas , Proteômica , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Zhongguo Gu Shang ; 34(1): 26-33, 2021 Jan 25.
Artigo em Zh | MEDLINE | ID: mdl-33666016

RESUMO

OBJECTIVE: To establish a three-dimensional finite element model of osteoporosis and to study the stiffness recovery of injured vertebrae and stress analysis of adjacent vertebrae after percutaneous vertebroplasty under different perfusion and distribution conditions by simulating fluid flow into the vertebral body. METHODS: A male healthy volunteer was selected. CT scans were performed from T11 to L2. Mimics 15.0 and ABAQUS 6.11 software were used to extract CT images. The vertebral model of osteoporotic fracture was established. The flow physical field and conduction and diffusion physical field were coupled to simulate the process and parts of the injection of bone cement into the vertebral fracture model. The amount of bone cement injected into the vertebral fracture model was 2 ml, 4 ml, 6 ml respectively. The diffusion range of bone cement was simulated on the image, and the post injection model of bone cement was obtained. Vertical downward, forward and backward pressure of 300 N were applied on the surface of the model to simulate vertebral movement. The stress changes of upper and lower vertebrae and diseased vertebrae under different conditions were calculated. RESULTS: (1) The VonMises stress of T12 inferior endplate was the largest in the three states before and after fracture.(2) The VonMises stress of the intervertebral disc and each endplate after fracture was significantly higher than before fracture. When percutaneous vertebroplasty was applied, as the amount of bone cement injection increases, the VonMises stress of the adjacent vertebral endplates increases. In the diseased vertebrae, as the amount of bone cement increases, the VonMises stress of the vertebral body endplate showed a downward trend. CONCLUSION: Reliable biomechanical model of lumbar vertebral fracture can be established by using CT scanning data through software simulation. Vertebral fracture and vertebroplasty will cause biomechanical changes of adjacent vertebral bodies. With the increase of bone cement injection, the influence of biomechanical changes will increase significantly. Neighbouring vertebral fractures are more likely. For this experiment, percutaneous vertebroplasty has a suitable amount of cement injection of 4 ml.


Assuntos
Fraturas por Compressão , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Fenômenos Biomecânicos , Cimentos Ósseos , Análise de Elementos Finitos , Fraturas por Compressão/cirurgia , Humanos , Vértebras Lombares/cirurgia , Masculino , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia
12.
J Photochem Photobiol B ; 213: 112070, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33142213

RESUMO

Owing to photocatalytic and antibacterial properties, bismuth based oxides has drawn much attention in recent past. However, non-recyclability of these oxides has restricted their practical applications. In present work, a novel nanostructured composite monoclinic bismuth vanadate@ activated carbon fibers (BiVO4@ACF) photocatalyst was efficaciously synthesized using a solvothermal method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and Bruner-Emmett-Teller (BET). The specific surface area, phase composition, microstructure, binding and photocatalytic activity of BiVO4@ACF pose great dependence on solvent nature and chelating agents utilized for synthesis. The photocatalytic and antibacterial potential of this composite was evaluated and optimized by using a model pollutant, Reactive Rhodamine Blue (RhB) and pathogenic microbes (Escherichia coli and Staphylococcus aureus). The composite possesses enhanced photocatalytic and antibacterial activity and was reutilized for three rounds of respective reaction without any loss of activity and structure as evident from SEM and XRD results. The photocatalytic mechanism of photodegradation of dye and bactericidal properties of samples under visible light irradiation was determined by scavenger and photoluminescence (PL) spectroscopy. The enhanced photocatalytic and antibacterial activity, chemical stability and most importantly good recyclability of BiVO4@ACFs highlight the potential application of this composite in water purification and other biological applications.


Assuntos
Antibacterianos/química , Bismuto/química , Fibra de Carbono/química , Nanoestruturas/química , Vanadatos/química , Poluição Química da Água/prevenção & controle , Catálise , Escherichia coli/metabolismo , Escherichia coli/efeitos da radiação , Radicais Livres/química , Luz , Fotólise , Rodaminas/química , Espectrometria de Fluorescência , Staphylococcus aureus/metabolismo , Staphylococcus aureus/efeitos da radiação , Difração de Raios X
13.
Materials (Basel) ; 13(18)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906747

RESUMO

In the internal thread extrusion forming, if the process parameters are not selected properly, the extrusion torque will increase, the extrusion temperature will be too high, or even the tap will break. In order to obtain effective process parameters under certain working conditions, this paper uses a combination of numerical simulation and process experiment to analyze the influence of the bottom hole diameter, extrusion speed, and friction factor on the extrusion torque and extrusion temperature. Through an orthogonal experiment, the significant influence law of different process parameters on the extrusion torque and extrusion temperature was studied, and the order of their influence was determined. Based on the optimal process parameters, numerical simulations and process tests were carried out, and the extrusion effect and related parameters were compared and analyzed. The results show that the extruded thread has clear contour, uniform tooth pitch, complete tooth shape, and good flatness. Compared with before optimization, the maximum extrusion torque has been reduced by 37.15%, the maximum temperature has been reduced by 29.72%, and the extrusion quality has been improved. It shows that the optimized method and optimized process parameters have good engineering practicability.

14.
Virus Res ; 263: 55-63, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30611822

RESUMO

Enterovirus A71 (EV-A71) is known for its manifestation as hand foot and mouth disease (HFMD), which has caused countless large-scale epidemic outbreaks throughout the world. However, the molecular pathogenesis of EV-A71 infection is still elusive. Previous studies found that the biological characteristics of a mild EV-A71 strain (SDLY1) and a severe EV-A71 strain (SDLY107) are significantly different, and sequence analysis showed that there are several differences in nucleotide sites of UTRs (88 nt, 123 nt, 143 nt, 154 nt, 187 nt, 241 nt, 243 nt, 253 nt, 291 nt, 438 nt, 440 nt, 571 nt, 579 nt, 602 nt, 658 nt, 664 nt, 690 nt, 696 nt, 7328 nt, 7335 nt, 7367 nt, and 7395 nt). The aim of this study was to determine whether these amino sites in UTRs are associated with the pathogenesis of EV-A71 and are responsible for different clinical manifestations. Based on the reverse genetics technology, we rescued two chimeric viruses SDLY107(1-5'UTR) and SDLY107(1-3'UTR) by replacing 5'UTR/3'UTR gene fragments of an infectious cDNA clone. Replication kinetics and cytotoxicity assays showed that the virulence of the two chimeric strains significantly changed in vitro. The viral loads of the two chimeric strains in infected ICR mice were reduced and pathological damage in the brains, lungs, intestinal tissues, and muscles were lightened. Our findings suggest that some nucleotide sites in UTRs may have a function in the pathogenicity and virulence of EV-A71.


Assuntos
Enterovirus Humano A/crescimento & desenvolvimento , Enterovirus Humano A/patogenicidade , Doença de Mão, Pé e Boca/patologia , Doença de Mão, Pé e Boca/virologia , RNA Viral/genética , Regiões não Traduzidas , Fatores de Virulência , Estruturas Animais/patologia , Estruturas Animais/virologia , Animais , Linhagem Celular , Sobrevivência Celular , Modelos Animais de Doenças , Enterovirus Humano A/genética , Humanos , Camundongos Endogâmicos ICR , Genética Reversa , Carga Viral , Virulência , Replicação Viral
15.
Viruses ; 12(1)2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861844

RESUMO

BACKGROUND: Enterovirus 71 (EV71) is the main pathogen that causes severe hand, foot, and mouth disease with fatal neurological complications. However, its neurovirulence mechanism is still unclear. Candidate virulence sites were screened out at structural protein VP1, but the function of these candidate virulence sites remains unclear. Several studies have shown that autophagy is associated with viral replication. However, the relationship between VP1 and autophagy in human neurons has not been studied. METHODS: A recombinant virus-SDLY107-VP1, obtained by replacing the VP1 full-length gene of the SDLY107 strain with the VP1 full-length gene of the attenuated strain SDJN2015-01-was constructed and tested for replication and virulence. We then tested the effect of the recombinant virus on autophagy in nerve cells. The effect of autophagy on virus replication was detected by western blot and plaque test. Finally, the changes of mTOR signaling molecules during EV71 infection and the effect of mTOR on virus replication at the RNA level were detected. RESULTS: Viral recombination triggered virulence attenuation. The replication ability of recombinant virus SDLY107-VP1 was significantly weaker than that of the parent strain SDLY107. The SDLY107 strain could inhibit autophagic flux and led to accumulation of autophagosomes, while the SDLY107-VP1 strain could not cause autophagosome accumulation. The synthesis of EV71 RNA was inhibited by inhibiting mTOR. CONCLUSIONS: Replacement of VP1 weakened the replication ability of virulent strains and reduced the level of autophagy in nerve cells. This autophagy facilitates the replication of virulent strains in nerve cells. VP1 is an important neurovirulence determinant of EV71, which affects virus replication by regulating cell autophagy. mTOR is a key molecule in this type of autophagy.


Assuntos
Proteínas do Capsídeo/metabolismo , Enterovirus Humano A/fisiologia , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/virologia , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Replicação Viral , Sequência de Aminoácidos , Autofagossomos , Autofagia , Biomarcadores , Proteínas do Capsídeo/química , Linhagem Celular Tumoral , Interações Hospedeiro-Patógeno , Humanos , Recombinação Genética
16.
Virus Res ; 244: 262-269, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29175108

RESUMO

Enterovirus 71 (EV71) can cause hand, foot, and mouth disease in children, and severe infections can induce neurological complications and even death. However, the pathogenesis of EV71 remains unknown. The 2A proteinase (2Apro) of EV71 plays an important role in segmenting the precursor polyprotein during viral replication, inhibiting host protein synthesis, and evading innate immunity. This study was to determine the function of EV71 2Apro in replication and virulence. A chimeric strain (SDLY 107-2A-1) was recombined by replacing 2Apro of a severe strain (SDLY107) with that of a mild strain (SDLY1) based on an infectious cDNA clone. The replication kinetics of the chimeric strain in vitro and in vivo were determined by qRT-PCR, which showed that the chimeric strain replicated slower and generated less viral RNA than the severe strain. The pathological change and viral load of chimeric strain infected mice were intermediate between severe strain infected mice and mild strain infected mice. Cellular cytotoxicity assays revealed that 2Apro was associated with the neurotoxicity of EV71. Histopathological and immunohistochemical assays detected tissue pathological damage in the lungs, muscles, brain, and intestinal tissues. Together, these results suggest that 2Apro modulates replication and virulence of EV71. This provides a theoretical basis for virulence determination of EV71.


Assuntos
Cisteína Endopeptidases/genética , Enterovirus Humano A/genética , Enterovirus Humano A/patogenicidade , Infecções por Enterovirus/virologia , RNA Viral/genética , Proteínas Virais/genética , Replicação Viral , Animais , Encéfalo/patologia , Encéfalo/virologia , Linhagem Celular Tumoral , Clonagem Molecular , Cisteína Endopeptidases/metabolismo , Modelos Animais de Doenças , Enterovirus Humano A/metabolismo , Infecções por Enterovirus/patologia , Expressão Gênica , Engenharia Genética , Humanos , Intestinos/patologia , Intestinos/virologia , Pulmão/patologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos ICR , Músculo Esquelético/patologia , Músculo Esquelético/virologia , Neurônios/patologia , Neurônios/virologia , RNA Viral/metabolismo , Recombinação Genética , Carga Viral , Proteínas Virais/metabolismo , Virulência
17.
Huan Jing Ke Xue ; 38(11): 4868-4873, 2017 Nov 08.
Artigo em Zh | MEDLINE | ID: mdl-29965434

RESUMO

Using ultrasonic assisted extraction, column chromatograph purification and gas chromatograph-mass spectrometer(GC-MS) analysis method to quantify the contents of seven kinds of organic phosphorus ester(OPEs) in plastic tracks in Chengdu City. The recovery rates of this method ranged from 71.41% to 110.58% and the correlation coefficient (r) of the standard curve was higher than 0.99, which demonstrates satisfying quality control. Plastic track samples were collected from twelve schools in Chengdu. The results show that OPEs are detected in two-thirds of plastic track samples. TnBP[Tri-n-butyl phosphate] and TEHP[tris(2-ethylhexyl) phosphate] were detected with high frequency, while TCEP[tri(2-chloroethyl) phosphate], TDCPP[tridichloropropyl phosphate] and TPhP[triphenyl phosphate] were not detected in any samples. Contents of the total OPEs (Σ7OPEs) in the plastic track ranged from ND to 534.89 ng·g-1. TnBP was identified at the highest content levels (ND-462.18 ng·g-1). TCPP[Trichloropropyl phosphate], a chlorinated phosphate with higher toxicity, was detected in one sample with a contents of 205.94 ng·g-1. The average exposure dose for adults was 0.14 ng·(kg·d)-1, lower than that for children of 0.64 ng·(kg·d)-1. Risk quotients of OPEs for adults and children were only 10-7 -10-5 and could be ignored. These results indicate that the government should limit the consumption, as well as the type of OPEs which are added to plastic tracks, to protect population health.


Assuntos
Ésteres/análise , Fósforo/análise , Plásticos , Adulto , Criança , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Medição de Risco
18.
Vector Borne Zoonotic Dis ; 17(6): 425-431, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28287930

RESUMO

INTRODUCTION: Recently, hantaviruses have been discovered in insectivores in Europe, Asia, Africa, and North America. Imjin virus (MJNV) was first isolated from the lung tissues of Ussuri white-toothed shrew (Crocidura lasiura) from South Korea in 2009. We aim to detect the species and prevalence of insectivore- and rodent-borne hantaviruses in shrews and rodents. MATERIALS AND METHODS: Shrews and rodents were captured in Jiaonan County of Shandong Province, China, in 2014. RT-PCR was used to amplify viral RNA of Hantavirus species, including insectivore-borne Imjin virus (MJNV), rodent-borne Hantaan virus (HTNV), and Seoul virus (SEOV) from shrews and rodents. RESULTS AND DISCUSSION: We found that MJNV infected 10.7% (19/178) of Crocidura shrews, but it infected none of rodents (0/475); we also found that 2 of 178 (1.1%) Crocidura shrews were PCR positive to SEOV. This study indicated that the major animal hosts of Imjin virus are shrews, and rodent-borne SEOV can infect shrews.


Assuntos
Orthohantavírus/isolamento & purificação , Musaranhos/virologia , Animais , China , Reservatórios de Doenças , Feminino , Orthohantavírus/genética , Masculino , Filogenia , Roedores/virologia , Zoonoses
19.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 24(5): 1511-1517, 2016 Oct.
Artigo em Zh | MEDLINE | ID: mdl-27784384

RESUMO

OBJECTIVE: To evaluate the effect of PEGylated IL-11 mutein (PEG-mIL 11) with different dose or injection frequency on thrombocytopenia in myelosuppressed mice and to compare its effect with mIL-11, so as to provide reference data for clinical use. METHODS: Myelosuppressive model with thrombocyopenia was produced in BALB/c mice by whole body 60Co γ-ray irradiation in dose of administration 2.5 Gy followed by i.p. injections of carboplatin at 50 mg/kg. In study of injection frequency, 30 thrombocytopenic BALB/c mice were randomly divided into 5 groups: vehicle control group (once daily on d1, 4, 7), mIL-11 group [200 µg/(kg·d)×9 d], PEG-mIL 11 A group [111800 µg/(kg·d)×1 d (d 1)], PEG-mIL 11 B group 900 µg/(kg·d)×2 d (d 1,5), and PEG-mIL 11 C group [600 µg/(kg·d)×3 d (d 1,4,7)]. The route of administration is subcutaneous injection. The platelet counts were monitored in the subsequant 5 weeks. In study of dose administration, 100 thrombocytopenic BALB/c mice were randomly divided into 5 groups: vehicle control group (once daily on d1 and 5), mIL-11 group 200 µg/(kg·d)×9 d, and PEG-mIL 11 low-, mid-, and high-dose groups (200, 420 and 900 µg/(kg·d)×2 d, once a day on d1 and 5). The route of administration is subcutaneous injection. The platelet counts were monitored every 2-3 days in the subsequant 5 weeks, and CFU-Meg was determined on d 8 of the bone marrow cells collection. RESULTS: After 60Co irradition and carboplatin injection, Plt level decreased with time, and a >80% reduction was noted at nadir when comparing with baseline. In frequency of administration study, the platelet nadir of the 3 PEG-mIL 11 groups were significantly higher than that of vehicle control and mIL-11 groups (P<0.05), while no significant difference was noted among the 3 groups of different administration frequences; In dose level study, the reduction of Plt count at the nadir in the 3 PEG-mIL 11 groups was significantly less than that of vehicle control and mIL-11 groups (P<0.05). And a rapid recovery of Plt count was found in the PEG-mIL 11 groups with a dose-dependent increase of Plt count on d 10. A lower reduction and a rapider recovery of RBC was also found in the PEG-mIL 11 groups. No significant effect on WBC was found for all the treatment groups. An increase in CFU-Meg was observed in PEG-mIL 11 and mIL-11 groups, with higher CFU-Meg in PEG-mIL 11 groups. CONCLUSION: A preventive effect of PEG-mIL 11 on thrombocytopenia in myelosuppressed mice has been confirmed. In comparison with mIL-11, a better effect of PEG-mIL 11 is obtained under lower dose frequency, indicating a better compliance of the treatment regimen, and providing a foundation for developing a long-acting preparation of rhIL-11.


Assuntos
Trombopoese , Animais , Plaquetas , Células da Medula Óssea , Carboplatina , Humanos , Interleucina-11 , Camundongos , Camundongos Endogâmicos BALB C , Contagem de Plaquetas , Polietilenoglicóis , Proteínas Recombinantes , Trombocitopenia , Trombopoetina
20.
Viruses ; 7(12): 6400-11, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26690202

RESUMO

Hand, foot, and mouth disease (HFMD), which has led to millions of attacks and several outbreaks across the world and become more predominant in Asia-Pacific Region, especially in Mainland China, is caused by several Human Enteroviruses including new enterovirus, coxsakievirus and echovirus. In recent years, much research has focused on the epidemiological characteristics of HFMD. In this article, multiple characteristics of HFMD such as basic epidemiology, etiology and molecular epidemiology; influencing factors; detection; and surveillance are reviewed, as these can be help protect high risks groups, prevalence prediction and policy making for disease prevention.


Assuntos
Enterovirus/classificação , Monitoramento Epidemiológico , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , China/epidemiologia , Enterovirus/genética , Enterovirus/isolamento & purificação , Feminino , Doença de Mão, Pé e Boca/diagnóstico , Humanos , Incidência , Masculino , Epidemiologia Molecular , Prevalência , Estações do Ano
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