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1.
Dalton Trans ; 47(15): 5390-5405, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29589612

RESUMO

Based on a Mn/Mo-metal organic framework (MOF) precursor, [Mn(4,4'-bipyridine)0.5 MoO4]·1.5H2O, a MnS/MoS2/C hybrid was synthesized through a calcination and sulfurization approach and it is mainly constituted by MoS2/C nanorods and MnS/MoS2/C nanoflakes. The MnS/MoS2/C hybrid delivers a high specific capacitance of 1162 F g-1 at 0.5 A g-1 in 2 M KOH electrolyte, and it possesses a good rate capacity with a retention of 75.7% (880 F g-1) at 10 A g-1, which is due to the synergetic effects of the components MnS, MoS2 and carbon matrix in the hybrid material. The carbon matrix in the hybrid material can not only anchor the active components of MnS and MoS2, but also transport electrons efficiently. The completely exposed Mo and S edges on the preferential 2H-(002) and 3R-(003) facets of MoS2 are beneficial for ion adsorption and electrochemical reaction. An asymmetric supercapacitor constructed by the MnS/MoS2/C hybrid (positive electrode) and activated carbon (AC) (negative electrode) exhibited a capacitance retention of 81% after 5000 galvanostatic charge-discharge cycles (GCD). During the GCD process, the metal sulfides were probably transformed into metal hydroxides in the presence of OH- electrolyte ions. In addition, the MnS/MoS2/C hybrid exhibits a visible light-driven photocurrent response, and DFT calculation proves that it is attributed to the semiconducting feature of MoS2 in the hybrid.

2.
Dalton Trans ; 46(24): 7866-7877, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28598483

RESUMO

Using a rigid ditopic ligand, 4,5-di(4'-carboxylphenyl)benzene (H2L), three coordination polymers (CPs) formulated as MnL(H2O)2 (1), CdL(H2O) (2) and Mn2L2(DMF)3 (3) have been synthesized and structurally characterized by single-crystal X-ray diffraction. These three CPs display 2D architectures but with different topologies. The experimental data and DFT calculation indicate that CP 2 is a semiconductor, and its CB/VB energy levels match with those of the perovskite CH3NH3PbI3. A FTO/TiO2/CH3NH3PbI3/CP 2 device is fabricated and the CP-based device shows much larger photoresponse under visible light illumination (650 nm > λ > 350 nm, 100 mW cm-2) than the individual CP 2. At 0 V vs. AgCl/Ag, the largest photocurrent density yielded by the CP-based perovskite device is ca. 200 times that of CP 2, which is due to the matched energy levels of all the materials in the device, leading the photogenerated electron-hole pairs to be separated effectively. Meanwhile, the coverage of the insoluble CP on the surface of the perovskite CH3NH3PbI3 can improve the stability of the perovskite against water.

3.
Virus Res ; 223: 52-6, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27354303

RESUMO

Duck Tembusu virus (DTMUV) has spread to the major duck-farming region in China, causing acute egg-production drop in Chinese duck population. In this study, we characterized a DTMUV strain (named GD2014) isolated from an egg-production drop duck farm in Guangdong province, South China. The virus was pathogenic to Muscovy duck embryos and caused severe egg production drop for laying Muscovy ducks. The genome sequence of GD2014 shared 97-99% homologies with other waterfowl-origin Tembusu viruses, and shared 89% identities with MM1775 strain isolated from mosquito. Phylogenetic analysis of entire open reading frame (ORF), E gene and NS5 gene indicated that GD2014 belonged to Ntaya group. These results have implications for understanding the orgin, emergence and pathogenicity of DTMUV as well as for the development of vaccines and diagnostics based on epidemiological data.


Assuntos
Patos/virologia , Infecções por Flavivirus/veterinária , Flavivirus/genética , Flavivirus/patogenicidade , Doenças das Aves Domésticas/virologia , Animais , Linhagem Celular , Feminino , Genoma Viral , Fases de Leitura Aberta , Filogenia , Reprodução , Análise de Sequência de DNA , Virulência
4.
J Vet Sci ; 16(3): 317-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25643797

RESUMO

As part of our ongoing influenza surveillance program in South China, 19 field strains of H9N2 subtype avian influenza viruses (AIVs) were isolated from dead or diseased chicken flocks in Guangdong province, South China, between 2012 and 2013. Hemagglutinin (HA) genes of these strains were sequenced and analyzed and phylogenic analysis showed that 12 of the 19 isolates belonged to the lineage h9.4.2.5, while the other seven belonged to h9.4.2.6. Specifically, we found that all of the viruses isolated in 2013 belonged to lineage h9.4.2.5. The lineage h9.4.2.5 viruses contained a PSRSSR↓GLF motif at HA cleavage site, while the lineage h9.4.2.6 viruses contained a PARSSR↓GLF at the same position. Most of the isolates in lineage h9.4.2.5 lost one potential glycosylation site at residues 200-202, and had an additional one at residues 295-297 in HA1. Notably, 19 isolates had an amino acid exchange (Q226L) in the receptor binding site, which indicated that the viruses had potential affinity of binding to human like receptor. The present study shows the importance of continuing surveillance of new H9N2 strains to better prepare for the next epidemic or pandemic outbreak of H9N2 AIV infections in chicken flocks.


Assuntos
Galinhas , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H9N2/genética , Doenças das Aves Domésticas/virologia , Animais , China , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A Subtipo H9N2/metabolismo , Influenza Aviária/virologia , Filogenia , Análise de Sequência de RNA/veterinária
5.
Vet Microbiol ; 175(2-4): 332-40, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25529828

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) was first reported in China since late 1995 and several variants were further reported in subsequence years, causing huge economic losses to the Chinese swine industry. To date, three major lineages (lineage 3, 5.1 and 8.7) of Type 2 PRRSV were reported in China based on our global genotyping. The present study provides the epidemiology of the PRRSV in South China based on the isolates collected during 2009-2012, indicating three lineages (lineage 3, 5.1 and 8.7) of Type 2 PRRSV were still circulating in this area. Our phylogenetic reconstruction indicated that lineage 3 re-emerged in 2010 formed a huge cluster with closely related to the 2004 isolates from Hong Kong. Furthermore, the inter-lineage genomic recombination between MLV vaccine strain (lineage 5) and a recently re-emerged lineage 3 virus (QYYZ) has also been found in a farm practicing MLV vaccination. Our in vivo experiment comparing the pathogenicity and clinical presentations among currently isolated viruses indicated that pigs infected with recombinant lineage 3 virus (GM2) showed persistent higher fever compared to pigs infected by its wild counterpart (QYYZ). This study enhanced our understanding on potential importance of the recombination of PRRSV along with their evolution.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Recombinação Genética , Vacinas Virais/imunologia , Animais , China , Genoma Viral , Genômica , Genótipo , Hong Kong , Filogenia , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Suínos , Virulência
6.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(8): 931-5, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25223175

RESUMO

OBJECTIVE: To explore the role of Compound Danshen Injection (CDI) in regulating the expression of aquaporin 3 (AQP3) in human amnion epithelium cells (hAECs), and to study the relation between c-Jun N-terminal kinase (JNK) signal pathway and AQP3. METHODS: hAECs were isolated and primarily cultured from term pregnancy with normal amniotic fluid volume and from term pregnancy with oligohydramnios, and then hAECs were further divided into four groups, i.e., the blank control group (A), the SP600125 group (B), the CDI group (C), and the SP600125 +CDI group (D). The cell viability was measured by cell counting kit-8 assay (CCK-8). The expression of total JNK, phosphorylated JNK, and AQP3 were determined by Western blot. RESULTS: (1) In hAECs with normal AFV or with oligohydramnios: There was no statistical difference in the cell viability or the expression of total JNK among the 4 groups (P > 0.05). But there was statistical difference in the expression of p-JNK (P < 0.05). Compared with A group, the expression of p-JNK was obviously down-regulated in B group, but obviously up-regulated in C group (P < 0.05). The expression of p-JNK was significantly lower in D group than in C group, but higher than that in A group or B group (P < 0.05).The AQP3 expression in the hAECs with normal amniotic fluid volume of C group and D group were higher than that in the A group (P < 0.05). However, there was no statistical difference in the AQP3 expression between C group and D group (P > 0.05). In hAECs with oligohydramnios, the expression of AQP3 obviously decreased in B group, but up-regulated in C group (both P < 0.05). The expression of AQP3 was lower in D group than in C group, but higher than in B group (P < 0.05). CONCLUSION: CDI could regulate the AQP3 expression in hAECs with oligohydramnios via activating the JNK signal pathway.


Assuntos
Âmnio/citologia , Aquaporina 3/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Âmnio/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/metabolismo , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Salvia miltiorrhiza
7.
Virus Genes ; 45(1): 181-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22528639

RESUMO

A total of 127 porcine samples were collected from 48 farms in six provinces in south China. The positive rate of porcine epidemic diarrhea virus (PEDV) was 43.0 % (55/127), and the co-infection rate of PEDV and transmissible gastroenteritis virus (TGEV) was 12.0 % (15/127). The partial S gene and complete M gene were amplified from PEDV-positive strains by RT-PCR, cloned, sequenced and compared with each other, as well as with the reference strains in GenBank. Sequence homology results of the partial S gene and complete M gene showed that all south China field PEDV strains had nucleotide (deduced amino acid) sequence identities of 86.7-98.7 % (83.2-99.3 %) and 96.1-100 % (95.0-100%), respectively, with the foreign reference strains reported in GenBank. Phylogenetic analysis of the partial S gene showed that all the south China PEDV strains and two Thailand strains (08UB01 and 08RB07) belong to the same group and differ genetically from European strains and early domestic strains. Phylogenetic analysis of the complete M gene showed that all south China PEDV strains have a close relationship with most of the strains in Korea and Thailand, but differ genetically from the vaccine strain (CV777).


Assuntos
Infecções por Coronavirus/veterinária , Filogenia , Vírus da Diarreia Epidêmica Suína/genética , Doenças dos Suínos/epidemiologia , Suínos/virologia , Animais , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Proteínas M de Coronavírus , Glicoproteínas de Membrana/genética , Vírus da Diarreia Epidêmica Suína/classificação , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Glicoproteína da Espícula de Coronavírus , Doenças dos Suínos/virologia , Proteínas do Envelope Viral/genética , Proteínas da Matriz Viral/genética
8.
J Biosci Bioeng ; 107(4): 460-3, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19332309

RESUMO

Brevinin-2GU, a member of a brevinin-2 family of antimicrobial peptides isolated from an extract of the skin of the Asian frog, Hylarana guntheri, displays significant insulin-releasing activity. In this study, in order to obtain relatively large quantity of functional brevinin-2GU protein, the coding sequence of brevinin-2GU gene was cloned into pET32a (+) vector and expression as a Trx fusion protein in Escherichia coli. The results indicated that the expression level of the fusion protein could reach up to 45% of the total cell proteins. the soluble fusion protein collected from the supernatant of the cell lysate was then separated by Ni(2+)-chelating chromatography and cleaved by Factor Xa protease to release mature brevinin-2GU. Our results showed that the final yield of the brevinin-2GU was 1.7 mg, the purified peptide displayed insulin-releasing activity similar to that of the purified brevinin that was reported earlier. This method allows production of sufficiently large amounts of brevinin-2GU peptide for functional and structural characterizations.


Assuntos
Proteínas de Anfíbios/genética , Peptídeos Catiônicos Antimicrobianos/genética , Escherichia coli/genética , Insulina/metabolismo , Sequência de Aminoácidos , Proteínas de Anfíbios/isolamento & purificação , Animais , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/farmacologia , Clonagem Molecular , Amplificação de Genes , Expressão Gênica , Secreção de Insulina , Plasmídeos/genética , Reação em Cadeia da Polimerase , Ranidae , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Espectrometria de Massas por Ionização por Electrospray
9.
J Virol Methods ; 155(1): 55-60, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18926852

RESUMO

A rapid detection assay based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) has been developed for detecting porcine reproductive and respiratory syndrome virus (PRRSV). The RT-LAMP assay utilized a set of six primers to amplify the open reading frame 6 (ORF6) of the PRRSV. The amplified products were analyzed by agarose gel electrophoresis or visualized by colorimetric method. The results demonstrated that the RT-LAMP assay detected all 22 different PRRSV isolates, had no cross-reaction with four other swine viruses (i.e., PCV2, SIV, CSFV, and PEDV), and obtained a 91.3% sensitivity in 23 positive clinical samples in reference to the permissive cells-based virus isolation procedure. Therefore, the RT-LAMP assay provides a specific and sensitive means for detecting PRRSV in a simple, fast, and cost-effective manner. Furthermore, the RT-LAMP assay can be performed in less well-equipped laboratories as well as fields.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Linhagem Celular , Síndrome Respiratória e Reprodutiva Suína/diagnóstico , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Sensibilidade e Especificidade , Suínos , Fatores de Tempo
10.
J Biosci Bioeng ; 103(5): 444-50, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17609160

RESUMO

SET and MYND domain-containing protein 3 (SMYD3) is a novel histone methyltransferase that plays an important role in transcriptional regulation in human carcinogenesis. It activates the transcription of a set of downstream genes. Of these downstream genes, there are several oncogenes and genes associated with cell adhesion (including those of N-Myc, CrkL, Wnt10b, L-selectin, CD31 and galectin-4), which have been shown to have effects on cell viability, adhesion, migration and metastasis by many studies. To determine whether SMYD3 has such functions, in this study, we examined these types of biological activities in mouse fibroblast NIH3T3 cells by stably transfecting the human SMYD3 gene. The SMYD3-gene-transfected cells showed an increased proliferation rate and became more resistant to cell death induced by dexamethasone. Furthermore, the SMYD3-transfected cells also exhibited increased rates of cell adhesion to both type IV collagen and endothelial cells, and enhanced cell migration ability in both two-dimensional and three-dimensional assays. This study is the first to show that the overexpression of the SMYD3 gene affects cell viability, adhesion and migration, indicating that SMYD3 may be a promising new target of therapeutic intervention for the treatment of cancers or other pathological processes associated with cell adhesion and migration.


Assuntos
Adesão Celular/fisiologia , Movimento Celular/fisiologia , Dexametasona/administração & dosagem , Histona-Lisina N-Metiltransferase/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Histona-Lisina N-Metiltransferase/genética , Camundongos , Células NIH 3T3 , Proteínas Recombinantes/metabolismo
11.
Curr Microbiol ; 54(5): 366-70, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17486407

RESUMO

Perinerin is a small antimicrobial peptide (AMP) isolated from an Asian marine clamworm, Perinereis aibuhitensis Grube. It shows marked activity in vitro against both Gram-negative and Gram-positive bacteria. To obtain it in large amounts, the coding sequence of perinerin was cloned into pET32a(+) vector and expression as a Trx fusion protein in Escherichia coli. The soluble fusion protein collected from the supernatant of the cell lyste was separated by Ni(2+)-chelating chromatography. The purified protein was then cleaved by Factor Xa protease to release mature perinerin. Final purification was achieved by ion-exchange chromatography. Recombinant perinerin exhibited a similar antimicrobial activity to the native perinerin. These works might provide a significant foundation for the following research on the action of mechanism of marine AMPs.


Assuntos
Anti-Infecciosos/metabolismo , Escherichia coli/metabolismo , Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Animais , Anti-Infecciosos/farmacologia , Western Blotting , Enzimas de Restrição do DNA/metabolismo , Escherichia coli/genética , Expressão Gênica , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Genéticos , Peptídeos/genética , Peptídeos/farmacologia , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia
12.
Artigo em Chinês | MEDLINE | ID: mdl-21162204

RESUMO

AIM: To study the effect of diabetes-like environment on the cardiac hypertrophy, cultured cardiomyocytes were used to study the effect of high insulin and high glucose on norepinephrine (NE)-induced cardiac hypertrophy. METHODS: Using cultured myocardial cells as a model, the cellular hypertrophy was observed. The contracting frequency was counted by the inverted microscope, the protein content was assayed with Lowry's method, the cardiomyocytes' volumes were measured by computer photograph analysis system, the protein synthesis was assayed with [3H] leucine intake method. RESULTS: The total cellular protein content, cellular volumes, cellular protein synthesis showed an increase in high insulin group and high glucose group compared with control group. High insulin and high glucose and NE group showed a further increase compared with high glucose and NE group. CONCLUSION: The high insulin itself induces hypertrophy of the cultured myocardial cells slightly. Meanwhile, imitating diabetes-like environment with high insulin and high glucose and NE can further accelerate hypertrophy of the cultured myocardial cells.


Assuntos
Cardiomegalia/metabolismo , Glucose/metabolismo , Insulina/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Cardiomegalia/induzido quimicamente , Células Cultivadas , Miócitos Cardíacos/metabolismo , Norepinefrina/efeitos adversos , Ratos , Ratos Sprague-Dawley
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