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1.
Anal Chem ; 90(18): 10837-10842, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30136575

RESUMO

The emerging field of plasmonics has promoted applications of optical technology, especially in plasmon-enhanced spectroscopy (PES). However, in plasmon-enhanced fluorescence (PEF), "metal loss" could significantly quench the fluorescence during the process, which dramatically limits its applications in analysis and high-resolution imaging. In this report, silver core silica shell-isolated nanoparticles (Ag@SiO2 NPs or SHINs) with a tunable thickness of shell are used to investigate the interactions between NPs and emitters by constructing coupling and noncoupling modes. The plasmonic coupling mode between Ag@SiO2 NPs and Ag film reveals an exceeding integrating spectral intensity enhancement of 330 and about 124 times that of the radiative emission rate acceleration for shell-isolated nanoparticle enhanced phosphorescence (SHINEP). The experimental findings are supported by theoretical calculations using the finite-element method (FEM). Hence, the SHINEP may provide a novel approach for understanding the interaction of plasmon and phosphorescence, and it holds great potential in surface detection analysis and singlet-oxygen-based clinical therapy.

2.
iScience ; 27(7): 110283, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39040063

RESUMO

The emergence of novel Omicron subvariants has raised concerns regarding the efficacy of immunity induced by prior Omicron subvariants breakthrough infection (BTI) or reinfection against current circulating Omicron subvariants. Here, we prospectively investigated the durability of antibody and T cell responses in individuals post Omicron BA.2.2 BTI, with or without subsequent Omicron BA.5 reinfection. Our findings reveal that the emerging Omicron subvariants, including CH.1.1, XBB, and JN.1, exhibit extensive immune evasion induced by previous infections. Notably, the level of IgG and neutralizing antibodies were found to correlate with subsequent Omicron BA.5 reinfection. Fortunately, T cell responses recognizing both Omicron BA.2 and CH.1.1 peptides were observed. Furthermore, Omicron BA.5 reinfection may alleviate immune imprinting induced by WT-vaccination, bolster virus-specific ICS+ T cell responses, and promote the phenotypic differentiation of virus-specific memory CD8+ T cells. Antigen-updated or T cell-conserved vaccines are needed to control the transmission of diverse emerging SARS-CoV-2 variants.

3.
Biomacromolecules ; 14(1): 117-23, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23215021

RESUMO

We explore the interactions between a fluorescein (FAM)-labeled single-stranded DNA (P), graphene oxide (GO), and a cationic conjugated polymer, poly [(9,9-bis(6'-N,N,N-trimethylammonium)hexyl)-fluorenylene phenylene dibromide] (PFP). It is found that the fluorescence change of P-GO-PFP system is dependent on the addition order of P and PFP. When adding PFP into P/GO complex, the fluorescence resonance energy transfer (FRET) from PFP to P is inefficient. If P is added to PFP/GO complex, efficient FRET is obtained. This may be attributed to the equal binding ability for P and PFP to GO. The results of time-resolved fluorescence and fluorescence anisotropy support the different fluorescent response under different addition order of P and PFP to GO. Based on the above phenomenon, we demonstrate a method to reduce the high background signal of a traditional PFP-based DNA sensor by introducing GO. In comparison to the use of single PFP, the combination of PFP with GO-based method shows enhanced sensitivity with a detection limit as low as 40 pM for target DNA detection.


Assuntos
DNA de Cadeia Simples/análise , Transferência Ressonante de Energia de Fluorescência/métodos , Grafite/análise , Óxidos/análise , Polímeros/análise , Cátions , DNA de Cadeia Simples/química , Fluoresceína/análise , Fluoresceína/química , Grafite/química , Óxidos/química , Polímeros/química
4.
Biol Pharm Bull ; 35(8): 1230-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22863918

RESUMO

Panax Notoginseng Saponins (PNS) have been well known to have anti-tumor activity and enhance cytotoxicity of some cancer chemotherapy agents, but the mechanisms underlying these effects are still unknown. This study investigates the effect of PNS on cytotoxicity of cisplatin and the relationship between this effect and the modulation of gap junctions (GJ) function by PNS in a transfected cell line. The cytotoxicity of cisplatin (0.25-1 µg/mL) was increased in the presence of GJ. Inhibition of gap junction by either GJ blocker or interception of Connexin (Cx) expression decreased the cytotoxicity of cisplatin. Increasing GJ function enhanced cytotoxicity of cisplatin, only in the cells with functional GJ. PNS (50-200 µg/mL) significantly enhanced cisplatin cytotoxicity, but this effect required functional gap junctions between the cells. Exposure of the cells to PNS (50-200 µg/mL) for 4 h leads to a significant enhance in dye coupling of GJ in a dose-dependent manner. These results suggest that PNS increases the cytotoxicity of cisplatin through enhancement of GJ activity.


Assuntos
Comunicação Celular/efeitos dos fármacos , Cisplatino/uso terapêutico , Junções Comunicantes/efeitos dos fármacos , Panax notoginseng/química , Fitoterapia , Saponinas/uso terapêutico , Neoplasias do Colo do Útero/fisiopatologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Comunicação Celular/fisiologia , Cisplatino/farmacologia , Conexinas/metabolismo , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Junções Comunicantes/fisiologia , Células HeLa , Interações Ervas-Drogas , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Saponinas/farmacologia , Transfecção , Neoplasias do Colo do Útero/tratamento farmacológico
5.
Chem Pharm Bull (Tokyo) ; 59(5): 541-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21532189

RESUMO

An on-line HPLC-diode array detection-flow injection chemiluminescence (HPLC-DAD-FICL) method was applied to estimate the difference of Puerariae lobatae and Puerariae thomsonii. Their chemical and active profiles could be obtained by HPLC-DAD-FICL in one run. Seventeen compounds in two species were tentatively identified by HPLC-electrospray ionization-MS (HPLC-ESI-MS) method. The main antioxidants were rapidly screened by active fingerprints coupled with MS data. Similarity and Hierarchical clustering analysis (HCA) were used to distinguish different samples. The results suggested that the chemical fingerprints of 16 batches of samples were similar by similarity evaluation, while HCA could discriminate the two species. The active fingerprints of Puerariae lobatae and Puerariae thomsonii were significantly different. More antioxidants were found in Puerariae lobatae than in Puerariae thomsonii. Main antioxidants, including 3'-hydroxypuerarin, genistein 8-C-glycoside-xyloside, puerarin, 6″-O-xylosylpuerarin, mirificin and daidzein in two species, may be reasonable markers for the discrimination of the two species. The integrated fingerprint based on the chemical and active characteristics may provide an objective quality evaluation for Puerariae lobatae and Puerariae thomsonii.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Análise de Injeção de Fluxo/instrumentação , Medições Luminescentes/instrumentação , Pueraria/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/classificação , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/classificação , Análise de Injeção de Fluxo/métodos , Luminescência , Medições Luminescentes/métodos , Pueraria/classificação , Padrões de Referência , Especificidade da Espécie , Vasodilatadores/análise , Vasodilatadores/química , Vasodilatadores/classificação
6.
Chin J Nat Med ; 11(5): 546-52, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24359782

RESUMO

AIM: To establish the Spectrum-Effect integrated fingerprint of Polygonum cuspidatum to evaluate the quality of P. cuspidatum. METHODS: An on-line HPLC-DAD-flow injection chemiluminescence (FICL) method was developed to investigate the quality of P. cuspidatum from different habitats based on the established Spectrum-Effect integrated fingerprint. RESULTS: Nineteen batches of samples of P. cuspidatum were evaluated for the similarity of their chromatographic and free radical scavenging fingerprints, and the results compared. Main antioxidants were estimated by regression analysis between peak areas of thirteen compounds and their activities. Some active compounds were identified by HPLC-ESI-MS. CONSULSIONS: The results indicated that main antioxidants in P. cuspidatum could be rapidly screened by the established Spectrum-Effect integrated fingerprint based on on-line HPLC-DAD-FICL, and would be more efficient and objective method to evaluate the quality of P. cuspidatum.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Fallopia japonica/química , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Análise de Injeção de Fluxo , Luminescência , Controle de Qualidade
7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 13(6): 951-3, 2005 Dec.
Artigo em Zh | MEDLINE | ID: mdl-16403257

RESUMO

To investigate the expression of pituitary tumor-transforming gene (PTTG) and basic fibroblast growth factor (b-FGF) in acute leukemia, as well as the relationship of their expression with prognosis in acute leukemia, expressions of PTTG and b-FGF in acute leukemia (AL) specimens were detected by immunocytochemical technique. The results showed that the expressions of PTTG and b-FGF in AL group were higher than that in the control group significantly (P < 0.01). In AL group, after chemotherapy, the expression of PTTG and b-FGF in de novo patients group was higher than in the complete remission patient group significantly (P < 0.01). The expressions of PTTG and b-FGF showed positive correlation (r = 0.61, P < 0.01). It is concluded that Up-regulation of PTTG and b-FGF expression may be involved in the progression of acute leukemia and correlated closely with therapeutic effect. Associated detection of PTTG and b-FGF may help to judge the malignancy degree and prognosis of acute leukemia.


Assuntos
Fator 2 de Crescimento de Fibroblastos/biossíntese , Leucemia/metabolismo , Proteínas de Neoplasias/biossíntese , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/biossíntese , Criança , Feminino , Humanos , Imuno-Histoquímica , Leucemia/tratamento farmacológico , Leucemia/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Securina
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