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1.
J Med Virol ; 91(8): 1553-1561, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30950067

RESUMO

Accumulating evidence indicates that persistent infection with high-risk oncogenic human papillomavirus (HPV) genotypes is the most important risk factor for cervical cancer, and that the distribution of HPV genotypes varies regionally. This study explored the prevalence and genotype distribution of HPV infection among Han, Yi, and Bai women in various regions of Dali Bai Autonomous Prefecture, Yunnan Province, China. This cross-sectional study included 2779 women (20-76 years old) who were referred for 21-HPV genotype array diagnostic from five regions of Dali Bai Autonomous Prefecture between February 2013 and May 2016. Statistical methods used included a the χ2 test, Fisher's exact test, t test, and logistic regression. Overall HPV prevalence in the study population was 7.6%. HPV-52, HPV-58, HPV-18, HPV-81, and HPV-16 were the most prevalent genotypes in the study area, and notably, the prevalence of HPV-58 was significantly higher among women in Heqing County than that in other regions. Univariate analysis showed that husband's age, region, fertility status, and parity were potential factors associated with HPV infection. Multivariate logistic regression analysis revealed that Heqing County was an independent risk factor for HPV infection among women in the Dali area, moreover, Yi women showed the highest risk for HPV infections. Overall, our finding emphasizing the urgent need for an HPV screening and prevention program in Heqing County and Yi women. We also suggest that HPV-related health education should be provided not only to women, but also to men, to reduce the risk of infection in women.

2.
Med Mycol ; 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30289464

RESUMO

Candida albicans is the most important fungal pathogen afflicting humans, particularly immunocompromised patients. However, currently available antifungal drugs are limited and ineffective against drug-resistant strains. The development of new drugs or alternative therapeutic approaches to control fungal infections is urgent and necessary. Photodynamic inactivation (PDI) is a new promising therapy for eradicating microorganism infections through combining visible light, photosensitizers, and oxygen to generate reactive oxygen species (ROS). Although cytoprotective responses induced by photodynamic therapy (PDT) have been well studied in cancer cells, the mechanisms by which C. albicans responds to PDI are largely unknown. In this study, we first demonstrated that PDI induces C. albicans Hog1p activation. Deletion of any of the SSK2, PBS2, and HOG1 genes significantly decreased the survival rate after photochemical reactions, indicating that the Hog1 SAPK pathway is required for tolerance to PDI. Furthermore, the basic leucine zipper transcription factor Cap1 that regulates several downstream antioxidant genes was highly expressed during the response to PDI, and loss of CAP1 also resulted in decreased C. albicans survival rates. This study demonstrates the importance of the Hog1 SAPK and the Cap1 transcription factor, which regulates in resistance to PDI-mediated oxidative stress in C. albicans. Understanding the mechanisms by which C. albicans responds to PDI and consequently scavenges ROS will be very useful for the further development of therapeutics to control fungal infectious diseases, particularly those of the skin and mucosal infections.

3.
Se Pu ; 31(4): 348-51, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23898633

RESUMO

Boronate affinity monolithic column is an important chromatographic medium for the selective isolation of the cis-diol containing compounds. However, it is difficult to control the micro-structure of the monolithic capillary during its preparation process. In this article, using melamine and tris (2,3-epoxypropyl) isocyanurate (TEPIC), both are highly symmetrical in molecular structure, as the copolymerizing reagents, a boronate affinity monolithic capillary with high specific surface was prepared by in-situ polymerization according to the "teamed boronate affinity" principle. The pH for binding with cis-diol containing compounds of this monolithic capillary was decreased to neutral range due to the teamed bonorate affinity. The specific surface area was dramatically increased due to the use of the highly symmetrical copolymerizing reagents, which was 80.3 m2/g and apparently higher than those for other boronate affinity monolithic capillaries reported in references.

4.
Analyst ; 138(1): 290-8, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23139927

RESUMO

Boronate affinity functionalized materials have recently drawn increasing attention due to their capability to selectively isolate and enrich glycoproteins and glycopeptides. As cheaper and more stable competitors to lectins, boronic acids are generally believed to yield a relatively wider spectrum specificity to glycoproteins. For better understanding and effective utilization of boronate affinity, it is necessary to establish if boronic acids exhibit lectin-like narrow specificity towards individual or a sub-class of glycoproteins. Here we report a pH manipulation strategy for fine-tuning the specificity of boronate affinity monoliths towards two sub-classes of glycoproteins, sialylated and nonsialylated glycoproteins. When the binding pH > the pK(a) of the boronic acid by one pH unit or more, the boronate affinity monolith preferentially binds to glycoproteins containing neutral sugars and excludes sialic acid containing glycoproteins due to electrostatic repulsion. When the binding pH < the pK(a) by one pH unit or more, the boronate affinity monolith binds to sialylated glycoproteins due to the exceptional binding affinity of the boronic acid towards sialic acid residues. The alternative specificity towards sialic acid and neutral sugar was first verified using an off-line combination of boronate affinity extraction with nano-ESI-Orbitrap MS/MS detection. The alternative specificity towards sialylated and nonsialylated glycoproteins was then demonstrated by means of off-line combination of boronate affinity extraction with MALDI-TOF MS. Finally, the developed approach was applied to the alternative extraction of intact sialylated and nonsialylated glycoproteins spiked in human serum.


Assuntos
Ácidos Borônicos/metabolismo , Glicoproteínas/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , Glicoproteínas/química , Glicoproteínas/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Modelos Moleculares , Ácido N-Acetilneuramínico/metabolismo , Concentração Osmolar , Ligação Proteica , Conformação Proteica , Especificidade por Substrato
5.
J Chromatogr A ; 1256: 114-20, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22883162

RESUMO

A new boronate-silica hybrid monolithic column was prepared using a one-pot approach with 3-acrylamidophenylboronic acid (AAPBA) as the boronate affinity ligand. The AAPBA-silica monolith exhibited several attractive advantages. First, it is highly hydrophilic, providing excellent specificity and avoiding the presence of organic solvent in the mobile phase. Second, due to its large surface area, it exhibited a high binding capacity, 49.5 µmol/mL, the highest among the boronate affinity monolithic columns appeared in the literature. Third, the monolith can bind with cis-diol containing compounds at pH as low as 6.5, which not only avoids the use of basic pH conditions at which the silica monolith may hydrolysis but also facilitates the applications to wider sample range. Finally, the hybrid monolithic column exhibited apparent secondary separation capability, which allows for two-dimensional (2D) separation of cis-diol compounds in a single column. Due to these merits, the AAPBA-silica hybrid monolithic column can be a promising separation medium for the analysis of cis-diol containing compounds.


Assuntos
Compostos de Boro/química , Cromatografia de Afinidade/métodos , Dióxido de Silício/química , Microscopia Eletrônica de Varredura , Compostos Orgânicos/química
6.
Nanotechnology ; 23(32): 325602, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22825396

RESUMO

Herein, we report a new and facile method for fabricating TiO(2)@mesoporous carbon hybrid materials. Uniform polydopamine (PDA) layers were coated onto the surface of titanate nanotubes (TNTs) and TiO(2) nanorods (TNDs) through the spontaneous adhesion and self-polymerization of dopamine during the dipping process. Core-shell mesoporous carbon nanotubes with TiO(2) nanorods or nanoparticles encapsulated inside (TiO(2)@MC) were then obtained by transforming PDA layers into carbonaceous ones through calcination in nitrogen at 800 °C. The thickness of the mesoporous carbon layers is tens of nanometers and can be controlled by adjusting the coated PDA layers through the self-polymerization reaction time. In addition, three-layered nanocomposites of TiO(2)@MC@MO (MO, metal oxide) can be readily prepared by utilizing PDA layers in TNTs@PDA or TNDs@PDA to adsorb the metal ions, followed by the calcination process.

7.
Chem Commun (Camb) ; 48(34): 4115-7, 2012 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-22434374

RESUMO

A benzoboroxole-functionalized monolithic column was synthesized, which exhibited the best specificity and affinity towards cis-diol containing biomolecules as compared with the boronate affinity monolithic columns reported as well as significant secondary separation capability under acidic conditions.


Assuntos
Benzeno/química , Ácidos Borônicos/química , Cromatografia de Afinidade/métodos , Adenosina/análogos & derivados , Adenosina/isolamento & purificação , Cromatografia Capilar Eletrocinética Micelar , Feminino , Glicoproteínas/isolamento & purificação , Humanos , Masculino , Nucleosídeos/isolamento & purificação , Polímeros/química , Porosidade , Urinálise/métodos
8.
J Chromatogr A ; 1228: 276-82, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-21925666

RESUMO

High resolution separation of intact glycoproteins, which is essential for many aspects such as finger-print profiling, represents a great challenge because one glycoprotein can exhibit many isoforms with close physicochemical properties. Monolithic columns are important separation media for the separation of intact proteins due to its significant advantages such as easy preparation, high column efficiency and high permeability. However, there are few reports on high resolution profiling of intact glycoproteins. Herein, we presented a polymeric weak anion exchange (WAX) monolithic capillary for high resolution separation of glycoprotein isoforms. A base monolith was first prepared through ring-opening polymerization between tris(2,3-epoxypropyl)isocyanurate and tri(2-aminoethyl), and then modified through reacting with ammonia aqueous solution to convert the unreacted epoxide moieties into primary amino groups. The prepared monolithic capillary was characterized in terms of morphology, pore size, hydrophilicity and reproducibility. The obtained WAX monolithic capillary exhibited desired through-pores and mesopore size, stable skeleton and hydrophilic nature. The performance of the capillary was evaluated using several typical glycoproteins such as α(1)-acid glycoprotein (AGP) as mode analytes. Effects of the experimental parameters on the glycoform resolution were investigated. Under the optimized separation conditions, the tested glycoproteins were all resolved into distinct glycoforms. A comparative investigation with capillary zone electrophoresis (CZE) revealed that this WAX column provided better selectivity as more isoforms were observed, although the resolution of some glycoprotein isoforms decreased.


Assuntos
Ânions/química , Cromatografia por Troca Iônica/métodos , Glicoproteínas/química , Animais , Bovinos , Cromatografia por Troca Iônica/instrumentação , Compostos de Epóxi/química , Glicoproteínas/análise , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Polímeros/química , Porosidade , Isoformas de Proteínas , Reprodutibilidade dos Testes , Cloreto de Sódio , Ureia/química
9.
Chem Commun (Camb) ; 47(28): 8169-71, 2011 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-21687891

RESUMO

A new Wulff-type boronate was designed and synthesized. Upon immobilization on a polymeric monolith and acidified as boronic acid, the ligand exhibited specific boronate affinity to cis-diol compounds at medium acidic pH condition.


Assuntos
Ácidos Borônicos/química , Ácidos Borônicos/metabolismo , Glicóis/metabolismo , Adenosina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Polímeros/química , Porosidade , Urinálise
11.
Talanta ; 82(1): 270-6, 2010 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-20685466

RESUMO

Boronate affinity solid phase microextraction (BA-SPME) is a new format appeared recently with great potential for specific extraction of cis-diol-containing compounds. Unlike conventional SPME, BA-SPME relies on covalent interactions and thereby features with specific selectivity, eliminated matrix effect and manipulable capture/release. However, only on-fiber BA-SPME and its off-line combination with high performance liquid chromatography (HPLC) have been reported so far. In this study, we report on-line coupling of in-tube BA-SPME with HPLC-electrospray ionization tandem mass spectroscopy (in-tube BA-SPME-HPLC-ESI-MS/MS) for the specific and sensitive determination of cis-diol-containing biomolecules. A boronate affinity extraction phase was prepared onto the inner surface of the capillary by copolymerization of vinylphenylboronic acid (VPBA) and ethylene glycol dimethacrylate (EDMA). The extraction conditions were optimized by choosing appropriate extraction/desorption solutions and extraction time. The extraction capacity, linear range, reproducibility and life-time were investigated. The developed method was successfully applied for the determination of dopamine in urine samples. Since many cis-diol-containing compounds are of great biological importance, the in-tube BA-SPME-HPLC method can be a promising tool.


Assuntos
Ácidos Borônicos/química , Cromatografia Líquida de Alta Pressão/métodos , Dopamina/análise , Dopamina/isolamento & purificação , Microextração em Fase Sólida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Modelos Lineares , Reprodutibilidade dos Testes , Fatores de Tempo
12.
J Chromatogr A ; 1216(47): 8421-5, 2009 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-19850296

RESUMO

Boronate affinity chromatography is an important tool for specific isolation of cis-diol-containing compounds such as glycoproteins, RNA and carbohydrates. Boronate functionalized monolithic capillaries have been recently developed for specific capture of cis-diol-containing small biomolecules, but the apparent hydrophobicity of the columns prevents them from specific capture of glycoproteins. In this paper, a hydrophilic boronate affinity monolithic capillary was prepared by in situ free radical polymerization, using 4-vinylphenylboronic acid (VPBA) and N, N'-methylenebisacrylamide (MBAA) as functional monomer and cross-linker, respectively. The prepared poly(VPBA-co-MBAA) monolithic capillary exhibited uniform open channel network and high density of accessible boronic acid. Due to the utilization of hydrophilic cross-linker, the prepared column was hydrophilic, allowing for specific capture of glycoproteins.


Assuntos
Ácidos Borônicos/química , Cromatografia de Afinidade/métodos , Glicoproteínas/química , Acrilamidas/química , Interações Hidrofóbicas e Hidrofílicas , Polímeros/química , Porosidade
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(9): 1896-8, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19778820

RESUMO

OBJECTIVE: To compare the effects of cartilage-perichondrium palisade complex and cartilage-perichondrium horseshoe complex in tympanoplasty for large tympanic membrane perforation. METHODS: Nineteen patients (19 ears) undergoing tympanoplasty with cartilage-perichondrium palisade complex and 20 patients (20 ears) with cartilage-perichondrium horseshoe complex were compared for postoperative hearing and closure rate of tympanic membrane perforation. RESULTS: The closure rates of the tympanic membrane were all 100% in both groups 3 months after the operation, while tympanoplasty with cartilage- perichondrium horseshoe complex resulted in significantly greater improvement of the postoperative air-bone gap in speech frequency. CONCLUSION: Both of the two auricular cartilage-perichondrium complexes produced good effects for repair large tympanic membrane perforation, but cartilage-perichondrium horseshoe complex can achieve better results in speech frequency.


Assuntos
Cartilagem da Orelha/transplante , Perfuração da Membrana Timpânica/cirurgia , Timpanoplastia/métodos , Adulto , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Reconstrutivos/métodos , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
15.
Anal Sci ; 24(7): 895-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18614832

RESUMO

An amperometric horseradish peroxidase (HRP) inhibition biosensor has been substantially constructed by the help of N,N-dicyclohexylcarbodiimide (DCC), N-hydroxysuccinimide (NHS). The preparation steps and the biosensor response to phenylhydrazine were monitored by electrochemical impedance spectroscopy (EIS), cyclic voltammetry, and chronoamperometry. The proposed biosensor could be applied to determine phenylhydrazine in a 0.10 M phosphate buffer solution containing 1.2 mM hydroquinone and 0.50 mM H(2)O(2) by phenylhydrazine, inhibiting the catalytic activity of the HRP enzyme in the reduction of H(2)O(2). The system was optimized to realize a reliable determination of phenylhydrazine in the range of 2.5 x 10(-7) to 1.1 x 10(-6) M with a detection limit of 8.2 x 10(-8) M and a correlation coefficient of 0.999. The modified electrode displayed good reproducibility, sensitivity and stability for the determination of phenylhydrazine.


Assuntos
Técnicas Biossensoriais/métodos , Peroxidase do Rábano Silvestre/antagonistas & inibidores , Fenil-Hidrazinas/análise , Análise Espectral/métodos , Técnicas Biossensoriais/instrumentação , Tampões (Química) , Catálise , Dicicloexilcarbodi-Imida/química , Dicicloexilcarbodi-Imida/metabolismo , Impedância Elétrica , Eletroquímica , Enzimas Imobilizadas , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Oxirredução , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Soluções , Análise Espectral/instrumentação , Succinimidas/química , Succinimidas/metabolismo
16.
Int J Mol Sci ; 9(3): 316-26, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19325751

RESUMO

The electrochemical behavior of o-nitrophenol was studied in detail with a glassy carbon electrode (GCE). The dependence of peak potential on pH indicated that equivalent electrons and protons were involved in the process of o-nitrophenol reduction. The interaction of o-nitrophenol with calf thymus DNA was investigated by adding DNA to the o-nitrophenol solution and by immobilizing DNA on GCE, respectively. The peak current decrement and peak potential shift in presence of DNA indicated that o-nitrophenol could interact with DNA. The result was demonstrated that the in situ DNA damage was detected by differential pulse voltammetry after the o-nitrophenol was electrochemically reduced.

17.
Anal Sci ; 23(5): 569-72, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17495403

RESUMO

A highly sensitive electrochemical biosensor for the detection of trace amounts of promethazine has been designed. Double stranded (ds)DNA molecules are immobilized onto a pretreated glassy carbon electrode (GCE(ox)) surface. The voltammetric behaviors of promethazine on DNA-modified electrode were explored by means of cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The promethazine gave rise to a pair of well-defined peaks, which appeared at E(pc) = 52 mV and E(pa) = 96 mV (vs. Ag/AgCl) in 0.10 M acetate buffer (pH 5.0). The peak current was linearly enhanced with increasing the concentration of promethazine. The calibration was linear for promethazine over the range of 4.7 x 10(-10) to 9.3 x 10(-9) M with a correlation coefficient of 0.999. The limit of detection (LODs) was 3.0 x 10(-10) M (S/N = 3). The modified electrode was applied to determine promethazine in human blood samples with satisfactory results.


Assuntos
Carbono/química , DNA/química , Eletroquímica/métodos , Prometazina/análise , Eletrodos , Prometazina/química
18.
Bioelectrochemistry ; 70(2): 416-20, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-16872916

RESUMO

Cytochrome c (Cyt c) was successfully immobilized on L-cysteine modified gold electrode by multicyclic voltammetry method. The electrochemical behavior of Cyt c on the L-cysteine modified electrode was explored. In 0.10 M, pH 7.0 phosphate buffer solution (PBS), Cyt c showed a quasi-reversible electrochemical redox behavior with E(pc)=0.180 V, E(pa)=0.208 V (versus Ag/AgCl). The Cyt c/L-cysteine modified electrode gave an excellent electrocatalytic activity towards the oxidation of nitric oxide, and the catalysis currents were proportional to the nitric oxide concentration in the range of 7.0 x 10(-7) to 1.0 x 10(-5) M, the linear regression equation is I (microA)=-0.124-0.003 C(NO) (microM), with a correlation coefficient 0.996, The detection limit was 3.0 x 10(-7) M (times the ratio of signal to noise, S/N=3).


Assuntos
Técnicas Biossensoriais/métodos , Cisteína/química , Citocromos c/química , Eletroquímica/métodos , Óxido Nítrico/análise , Óxido Nítrico/química , Adsorção , Técnicas Biossensoriais/instrumentação , Catálise , Condutividade Elétrica , Eletroquímica/instrumentação , Eletrodos , Oxirredução
19.
Anal Sci ; 22(8): 1071-4, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16896244

RESUMO

DNA was immobilized on glassy carbon electrodes to fabricate DNA-modified electrodes. The direct electron transfer of horse heart cytochrome c on DNA-modified glassy carbon electrode was achieved. A pair of well-defined redox peaks of cytochrome c appeared at Epc = -0.017 V and Epa = 0.009 V (vs. Ag/AgCl) in 10 mM phosphate buffer solution (pH 7.0) at a scan rate of 50 mV/s. The electron transfer coefficient (alpha) and the standard rate constant of the surface reaction (Ks) of cytochrome c on DNA-modified electrodes could be estimated to be 0.87 and 34.52 s(-1), respectively. The DNA-modified glassy carbon electrode could be applied to detect cytochrome c by means of differential pulse voltammetry (DPV). The cathodic peak current was proportional to the quantity of cytochrome c in the range of 4.0 x 10(-6) M to 1.2 x 10(-5) M. The correlation coefficient is 0.996, and with the detection limit was 1.0 x 10(-6) M (three times the ratio of signal to noise, S/N = 3).


Assuntos
Técnicas Biossensoriais , Carbono/química , Citocromos c/análise , DNA/química , Eletroquímica/métodos , Eletrodos , Calibragem , Citocromos c/química , Citocromos c/metabolismo , Enzimas Imobilizadas/química , Concentração de Íons de Hidrogênio , Oxirredução , Propriedades de Superfície
20.
Bioelectrochemistry ; 69(2): 254-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16698326

RESUMO

A L-cysteine (L-Cys) self-assembled modified gold electrode was used to detect dopamine (DA) by chronoamperometric method (CE) in the presence of ascorbic acid (AA). The defective limit is 2.0 x 10(-8) mol L(-1) (S/N=3). The proposed method was applied to detect DA in the samples with satisfied result.


Assuntos
Ácido Ascórbico/química , Técnicas Biossensoriais/instrumentação , Cisteína/química , Dopamina/análise , Eletroquímica/instrumentação , Ouro/química , Microeletrodos , Adsorção , Técnicas Biossensoriais/métodos , Materiais Revestidos Biocompatíveis/química , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Ligação Proteica
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