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1.
Opt Express ; 22(9): 10675-81, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24921768

RESUMO

In this paper, we demonstrate that spoof surface magnon polaritons (SSMPs) can propagate along a corrugated perfect magnetic conductor (PMC) surface. From duality theorem, the existence of surface electromagnetic modes on corrugated PMC surfaces are manifest to be transverse electric (TE) mode compared with the transverse magnetic (TM) mode of spoof surface plasmon plaritons (SSPPs) excited on corrugated perfect electric conductor surfaces. Theoretical deduction through modal expansion method and simulation results clearly verify that SSMPs share the same dispersion relationship with the SSPPs. It is worth noting that this metamaterial will have more similar properties and potential applications as the SSPPs in large number of areas.

2.
Opt Express ; 21(20): 23803-11, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-24104291

RESUMO

Graphene can be used as a platform for tunable absorbers for its tunability of conductivity. In this paper, we proposed an "uneven dielectric slab structure" for the terahertz (THz) tunable absorber based on graphene. The absorber consists of graphene-dielectric stacks and an electric conductor layer, which is easy to fabricate in the manufacturing technique. Fine tuning of the absorption resonances can be conveniently achieved by adjusting the bias voltage. Both narrowband and broadband tunable absorbers made of this structure are demonstrated without using a patterned graphene. In addition, this type of graphene-based absorber exhibits stable resonances with a wide range angles of obliquely incident electromagnetic waves.

3.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 4): o512, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23634058

RESUMO

The title compound, C18H24NO3 (+)·Cl(-)·H2O, was synthesized by the reaction of propranolol hydro-chloride with acetyl chloride in chloro-form followed by slow evaporation in air. In the cation, the dihedral angle between the planes of the naphthalene ring system and the acetate group is 71.1 (2)°. An intra-molecular N-H⋯O hydrogen bond results in the formation of a non-planar pseudo-ring, with the ether O and the H atom displaced by -1.328 (2) and 0.65 Å, respectively, from the plane of the other ring atoms. The cation and anion are linked by an N-H⋯Cl hydrogen bond. The water molecule is linked to a methyl H atom by C-H⋯O hydrogen bond.

4.
Antiviral Res ; 75(3): 250-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17475344

RESUMO

A novel antiviral protein was purified from an extract of Grifola frondosa fruiting bodies using a procedure that included 40% ammonium sulfate precipitation and DEAE-cellulose ion exchange chromatography, and designated GFAHP. This protein inhibited herpes simplex virus type 1 (HSV-1) replication in vitro with an IC(50) value of 4.1 microg/ml and a therapeutic index >29.3. Higher concentrations of GFAHP (125 and 500 microg/ml) also significantly reduced the severity of HSV-1 induced blepharitis, neovascularization, and stromal keratitis in a murine model. Topical administration of GFAHP to the mouse cornea resulted in a significant decrease in virus production (mean virus yields: 3.4log10PFU in the treated group and 4.19log10PFU in the control group). We proved that GFAHP directly inactivates HSV-1 while simultaneously inhibiting HSV-1 penetration into Vero cells. Gel electrophoresis showed that GFAHP had a molecular weight of 29.5 kDa. GFAHP was tryptic digested and analyzed from the PMF of matrix assisted desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and nanoelectrospray ionization tandem mass spectrometry. The N-terminal sequence of GFAHP consisted of an 11 amino acid peptide, NH(2)-REQDNAPCGLN-COOH that did not match any known amino acid sequences, indicating that GFAHP is likely to be a novel antivirus protein. To our knowledge, this is the first report that characterizes an anti-HSV protein from G. frondosa.


Assuntos
Antivirais/isolamento & purificação , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/uso terapêutico , Grifola/química , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 1/efeitos dos fármacos , Ceratite Herpética/tratamento farmacológico , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Linhagem Celular , Córnea/virologia , Feminino , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/farmacologia , Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Ceratite Herpética/virologia , Camundongos , Camundongos Endogâmicos BALB C , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Replicação Viral/efeitos dos fármacos
5.
Antiviral Res ; 72(2): 162-5, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16846649

RESUMO

In this study, D-fraction extracted from Grifola frondosa (GF-D) and its combination with human interferon alpha-2b (IFN) were investigated for the inhibitory effect on hepatitis B virus (HBV) in HepG2 2.2.15 cells (2.2.15 cells). HBV DNA and viral antigens were analyzed by a quantitative real-time polymerase chain reaction and end-point titration in radioimmunoassays, respectively. The results showed that GF-D or IFN alone could inhibit HBV DNA in 2.2.15 cells with the 50% inhibitory concentration (IC50) of 0.59 mg/ml and 1399 IU/ml, respectively. We further investigated the combination of GF-D and IFN for anti-HBV activity and found that they synergistically inhibited HBV replication in 2.2.15 cells. In combination with 0.45 mg/ml GF-D, the apparent IC50 value for IFN was 154 IU/ml. This 9-fold increase in antiviral activity of IFN suggested that GF-D could synergize with IFN. These results indicate that GF-D, in combination with IFN, might provide a potentially effective therapy against chronic HBV infections.


Assuntos
Antivirais/farmacologia , Grifola/química , Vírus da Hepatite B/efeitos dos fármacos , Interferon-alfa/farmacologia , Antivirais/isolamento & purificação , Linhagem Celular Tumoral , DNA Viral/análise , Sinergismo Farmacológico , Antígenos da Hepatite B/análise , Vírus da Hepatite B/fisiologia , Humanos , Interferon alfa-2 , Reação em Cadeia da Polimerase , Proteínas Recombinantes , Replicação Viral/efeitos dos fármacos
6.
J Virol Methods ; 128(1-2): 156-61, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15964082

RESUMO

The transmission of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is associated with close contact to SARS patients and droplet secretions of those patients. The finding of positive RT-PCR results from stools of SARS patients suggests that stools of SARS patients or sewage containing stools of patients could transmit SARS-CoV. We used a novel style of electropositive filter media particle to concentrate the SARS-CoV from the sewage of two hospitals receiving SARS patients in Beijing. We also used cell culture, RT-PCR and gene sequencing to detect and identify the viruses from sewage. No infectious SARS-CoV contamination was found in any of the samples collected, but the nucleic acid of SARS-CoV could be detected in the sewage from the two hospitals before disinfection. While the RNA was only detected in three samples from the 309th Hospital, the others were negative after disinfection. These findings provide strong evidence that SARS-CoV can be excreted through the stool/urine of patients into sewage system, thus making the sewage system a possible route of transmission.


Assuntos
Hospitais , Síndrome Respiratória Aguda Grave/transmissão , Síndrome Respiratória Aguda Grave/virologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/classificação , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/isolamento & purificação , Esgotos/virologia , China , Desinfecção/métodos , Fezes/virologia , Filtração/métodos , Humanos , Reação em Cadeia da Polimerase , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Sensibilidade e Especificidade , Virologia/métodos , Cultura de Vírus
7.
World J Gastroenterol ; 11(28): 4390-5, 2005 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-16038039

RESUMO

AIM: To study whether severe acute respiratory syndrome coronavirus (SARS-CoV) could be excreted from digestive system. METHODS: Cell culture and semi-nested RT-PCR were used to detect SARS-CoV and its RNA from 21 stool and urine samples, and a kind of electropositive filter media particles was used to concentrate the virus in 10 sewage samples from two hospitals receiving SARS patients in Beijing in China. RESULTS: It was demonstrated that there was no live SARS-CoV in all samples collected, but the RNA of SARS-CoV could be detected in seven stool samples from SARS patients with any one of the symptoms of fever, malaise, cough, or dyspnea, in 10 sewage samples before disinfection and 3 samples after disinfection from the two hospitals. The RNA could not be detected in urine and stool samples from patients recovered from SARS. CONCLUSION: Nucleic acid of SARS-CoV can be excreted through the stool of patients into sewage system, and the possibility of SARS-CoV transmitting through digestive system cannot be excluded.


Assuntos
Sistema Digestório/virologia , Síndrome Respiratória Aguda Grave/transmissão , Síndrome Respiratória Aguda Grave/virologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/isolamento & purificação , Desinfecção , Fezes/virologia , Humanos , Reação em Cadeia da Polimerase/métodos , RNA Viral/isolamento & purificação , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Esgotos/virologia
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 38(4): 257-60, 2004 Jul.
Artigo em Zh | MEDLINE | ID: mdl-15312586

RESUMO

OBJECTIVE: In order to explore the existence of SARS coronavirus (Co-V) and/or its RNA in sewage of hospitals administered SARS patients. METHODS: A novel electropositive filter was used to concentrate the SARS-CoV from the sewage of two hospitals administered SARS patients in Beijing, including twelve 2,500 ml sewage samples from the hospitals before disinfection, and ten 25,000 ml samples after disinfection; as well as cell culture, RT-PCR and sequencing of gene to detect and identify the viruses from sewage. RESULTS: There was no live SARS-CoV detected in the sewage in this study. The nucleic acid of SARS-CoV had been found in the 12 sewage samples before disinfection from both hospitals by semi-nested PCR. After disinfection, SARS-CoV RNA could only be detected from the samples from the 309th Hospital, and the others were negative. CONCLUSION: It provides evidence that there is no live SARS-Cov in the sewage from hospitals with SARS patients though SARS-CoV RNA can be detected.


Assuntos
RNA Viral/análise , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/isolamento & purificação , Esgotos/virologia , Hospitais , Humanos , Nucleocapsídeo/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Síndrome Respiratória Aguda Grave/virologia
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