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1.
J Oral Maxillofac Surg ; 78(8): 1397-1402, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32386974

RESUMO

PURPOSE: Differentiating between bilateral condylar resorption (CR) and mandibular hypoplasia (MH) can be challenging owing to the difficulty in chronological observation and establishing standardized measurements. The purpose of the present study was to assess whether temporomandibular joint (TMJ) function can distinguish between CR and MH and clarify the essential diagnostic imaging tools for CR. MATERIALS AND METHODS: We performed a cross-sectional study of patients with mandibular retrognathia. The primary predictor variables were a clinical dysfunction score for the TMJ, mandibular plane angle (MPA), SNA angle, SNB angle, and cortical erosion score in the condylar heads. The demographic variables were age, anterior disc displacement, and previous orthodontic treatment. The anatomic variable was the condylar height (CH). The primary outcome variable was the disease status (CR or MH). The patients were divided into the CR group and MH group. The patients with CR were selected on the basis of a CH value of less than 22 mm. TMJ function was assessed using the Helkimo clinical dysfunction index. The CH on panoramic radiographs was measured using the Kjellberg method. The MPA, SNA angle, and SNB angle were analyzed using cephalometric analysis. Cortical erosion in the condylar head was assessed using computed tomography and magnetic resonance imaging. RESULTS: A total of 23 female participants were enrolled in the present study. The average clinical dysfunction score for the TMJ was 4.4 in the CR group and 0.4 in the MH group (P < .05). The average MPA was 41.2° in the CR group and 35.5° in the MH group (P < .05). CONCLUSIONS: The present investigation has shown that assessing TMJ function and analyzing MPA using a cephalometric radiograph can differentiate CR from MH.


Assuntos
Luxações Articulares , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Cefalometria , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Côndilo Mandibular/diagnóstico por imagem , Articulação Temporomandibular , Disco da Articulação Temporomandibular/diagnóstico por imagem
2.
Sensors (Basel) ; 18(1)2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29361775

RESUMO

Alizarin red S (ARS) was confined in layer-by-layer (LbL) films composed of phenylboronic acid-modified poly(ethyleneimine) (PBA-PEI) and carboxymethylcellulose (CMC) to study the voltammetric response to diol and polyol compounds. The LbL film-coated gold (Au) electrode and quartz slide were immersed in an ARS solution to uptake ARS into the film. UV-visible absorption spectra of ARS-confined LbL film suggested that ARS formed boronate ester (ARS-PBS) in the film. The cyclic voltammetry of the ARS-confined LbL film-coated electrodes exhibited oxidation peaks at -0.50 and -0.62 V, which were ascribed to the oxidation reactions of ARS-PBS and free ARS, respectively, in the LbL film. The peak current at -0.62 V increased upon the addition of diol or polyol compounds such as L-dopa, glucose, and sorbitol into the solution, depending on the concentration, whereas the peak current at -0.50 V decreased. The results suggest a possible use of ARS-confined PBA-PEI/CMC LbL film-coated Au electrodes for the construction of voltammetric sensors for diol and polyol compounds.

3.
Anal Chem ; 82(11): 4333-6, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20459059

RESUMO

"Sandwich-type" noncompetitive (immunometric) assays allow for high-sensitivity high-throughput macromolecule sensing and determination but cannot be used on small molecules (haptens). Here, we isolated single-chain Fv fragments from a phage-display library, which bound to complexes of particular haptens (vitamin D and A derivatives) with immobilized beta-cyclodextrin or beta-maltosyl residues, and formed ternary complexes. These scFvs enabled novel "semisandwich-type" immunometric assays of haptens with nanomole-range sensitivities.


Assuntos
Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Oligossacarídeos/metabolismo , Animais , Configuração de Carboidratos , Bovinos , Haptenos/análise , Haptenos/química , Haptenos/imunologia , Ensaios de Triagem em Larga Escala , Modelos Moleculares , Soroalbumina Bovina/metabolismo , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/metabolismo , beta-Ciclodextrinas/química , beta-Ciclodextrinas/metabolismo
4.
Biochem Biophys Res Commun ; 379(3): 743-8, 2009 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-19118520

RESUMO

REG (Regenerating gene) Ialpha protein functions as a growth factor for gastrointestinal cancer cells, and its mRNA expression is strongly associated with a poor prognosis in gastrointestinal cancer patients. We here demonstrated that PPARgamma-agonist thiazolidinediones (TZDs) inhibited cell proliferation and REG Ialpha protein/mRNA expression in gastrointestinal cancer cells. TZDs inhibited the REG Ialpha gene promoter activity, via its cis-acting element which lacked PPAR response element and could not bind to PPARgamma, in PPARgamma-expressing gastrointestinal cancer cells. The inhibition was reversed by co-treatment with a specific PPARgamma-antagonist GW9662. Although TZDs did not inhibit the REG Ialpha gene promoter activity in PPARgamma-non-expressing cells, PPARgamma overexpression in the cells recovered their inhibitory effect. Taken together, TZDs inhibit REG Ialpha gene transcription through a PPARgamma-dependent pathway. The TZD-induced REG Ialpha mRNA reduction was abolished by cycloheximide, indicating the necessity of novel protein(s) synthesis. TZDs may therefore be a candidate for novel anti-cancer drugs for patients with gastrointestinal cancer expressing both REG Ialpha and PPARgamma.


Assuntos
Neoplasias Gastrointestinais/genética , Litostatina/antagonistas & inibidores , Tiazolidinedionas/farmacologia , Transcrição Gênica/efeitos dos fármacos , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Litostatina/genética , PPAR gama/biossíntese , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética
5.
Chem Commun (Camb) ; (13): 1709-11, 2009 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-19294270

RESUMO

The phenylboronic acid azoprobe (BA-Azo)/gamma-cyclodextrin (gamma-CD) complex exhibits a selective response for D-glucose by forming a supramolecular 2:1 inclusion complex of the azoprobes with D-glucose inside the gamma-CD cavity.


Assuntos
Ácidos Borônicos/química , Glucose/química , gama-Ciclodextrinas/química , Espectrofotometria Ultravioleta
6.
J Nanosci Nanotechnol ; 8(1): 353-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18468082

RESUMO

Study of the interaction between gold nanoparticles and a series of amino acids is reported in this paper. Amino acids with thiol, amine, or hydroxyl groups in their side chains are proven to make gold nanoparticles self-assemble under certain conditions. There is a progression of the effect on self-assembly of gold nanoparticles from hydroxyl < amine < thiol. Meanwhile, concentration of amino acids and the pH value of the solution have been found to be important for amino acids to exert the interesting effect on self-assembly of the nanoparticles.


Assuntos
Aminoácidos/química , Colorimetria/métodos , Ouro/química , Nanopartículas Metálicas , Microscopia Eletrônica de Transmissão
7.
Anal Sci ; 24(2): 207-12, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18270410

RESUMO

An inclusion complex consisting of a fluorescent phenylboronic acid (C1-APB) and beta-cyclodextrin (beta-CD) acts as a supramolecular saccharide sensor whose response mechanism is based on photoinduced electron transfer (PET). This study evaluated four kinds of cyclodextrins (alpha-CD, beta-CD, gamma-CD, and NH(2)-beta-CD) by comparing their pH profiles, and confirmed that beta-CD was the best host for C1-APB because the C1-APB/beta-CD complex exhibited high affinity for saccharides as well as high fluorescent recovery upon saccharide binding. An investigation of the beta-CD concentration effect revealed the formation of a 1:1 inclusion complex of C1-APB with beta-CD. The observed saccharide selectivity of the C1-APB/beta-CD complex is in the following order: D-fructose (4039 +/- 69 M(-1)) > D-ribose (1083 +/- 26 M(-1)) > L-arabinose (474 +/- 11 M(-1)) > D-galactose (318 +/- 3 M(-1)) > maltotoriose (135 +/- 5 M(-1)) > D-glucose (114 +/- 2 M(-1)) > maltose (81 +/- 2 M(-1)). In addition to monomer emission, dimer emission from pyrene dimers was observed in the spectra for the C1-APB/gamma-CD complex, which allowed a ratiometric analysis. This study shows that the combination of a simple fluorescent probe, C1-APB, with various CDs diversifies the response systems for saccharide recognition.


Assuntos
Ácidos Borônicos/química , Carboidratos/análise , Ciclodextrinas/química , Corantes Fluorescentes/química , Elétrons , Fluorescência , Concentração de Íons de Hidrogênio , Substâncias Macromoleculares/química , Estrutura Molecular , Fotoquímica , Sensibilidade e Especificidade , Água/química , beta-Ciclodextrinas/química
8.
Biosens Bioelectron ; 22(8): 1600-4, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16905304

RESUMO

Direct electron transfer reactions of microperoxidase were achieved with the help of semiconductive zinc oxide nanoparticles on a pyrolytic graphite electrode. The enzyme could also exhibit fine electrocatalytic activity towards the reduction of hydrogen peroxide. Thereby, a hydrogen peroxide biosensor was constructed based on the electrocatalysis of microperoxidase. Further studies revealed that after irradiating the microperoxidase/zinc oxide nanoparticles co-modified electrode with UV light for 4h, the catalytic ability of microperoxidase could be greatly promoted, which could be beneficial to developing more sensitive hydrogen peroxide biosensors. As comparison, it was found that the catalytic activity of the enzyme would be depressed if microperoxidase/agarose co-modified electrode was irradiated. We supposed it was the photovoltaic effect of the zinc oxide nanoparticles that improved the catalytic ability of microperoxidase.


Assuntos
Técnicas Biossensoriais/métodos , Peróxido de Hidrogênio/análise , Nanopartículas , Peroxidases/metabolismo , Óxido de Zinco/farmacologia , Catálise , Eletroquímica
9.
Anal Sci ; 23(3): 249-51, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17372363

RESUMO

The fluorescence of 4-(4'-dimethylamino)styryl-1-methylpyridinium (C1SP) was enhanced by more than 33-fold by complexation with beta-cyclodextrin (beta-CD) bearing a naphthalene, pyrene, or phenylboronic acid group. The great enhancement of the fluorescence of C1SP was due to a pi-pi stacking interaction, by which the bond rotation of C1SP was effectively suppressed. The results indicate that C1SP and structurally related hemicyanine dyes potentially become powerful fluorescent indicators for aromatic compounds through the pi-pi stacking interaction in water.


Assuntos
Ciclodextrinas/química , Fluorescência , Corantes Fluorescentes/química , Compostos de Piridínio/química , Estrutura Molecular
10.
Anal Sci ; 23(10): 1167-71, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17928662

RESUMO

Supramolecular complex formation of phenylboronic-acid-modified beta-cyclodextrin (1) with 1-methyl-4-(4-dimethylaminostyryl)pyridinium (C1SP) in aqueous solutions containing saccharides was fully clarified to gain an insight into the observed D-glucose (D-glc) selectivity of a supramolecular fluorescent probe composed of 1 and the 1-heptyl analogue of C1SP (Chem. Commun., 2006, 4319). At pH 9.6, where 1 was in its anionic form, both the stability and the fluorescence of the 1/C1SP complex were reduced by the formation of boronate esters of 1 with saccharides. Among the saccharides, D-glc had the smallest effect on destabilization of the 1/C1SP complex, almost completely retaining the fluorescence of the 1/C1SP complex that was reduced by other saccharides by approximately 2/3. Under neutral conditions, D-glc enhanced the fluorescence of the 1/C1SP complex by increasing the fraction of anionic 1 while minimally decreasing the stability and fluorescence of the 1/C1SP complex. Although other saccharides also increased the fraction of the anionic 1, their relatively large effects on the destabilization and reduction of fluorescence of the 1/C1SP complex limited the enhancement of the fluorescence of the 1-C1SP system under neutral conditions.


Assuntos
Ácidos Borônicos/química , Glucose/química , Compostos de Piridínio/química , beta-Ciclodextrinas/química , Fluorescência , Estrutura Molecular
11.
Materials (Basel) ; 10(6)2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28772942

RESUMO

The preparation of redox-active coatings is a key step in fabricating electrochemical biosensors. To this goal, a variety of coating materials have been used in combination with redox-active compounds. In this study, alizarin red S (ARS) was confined in layer-by-layer (LbL) films composed of poly(ethyleneimine) (PEI) and carboxymethylcellulose (CMC) to study the redox properties. A gold (Au) disc electrode coated with PEI/CMC LbL film was immersed in an ARS solution to uptake ARS into the film. ARS was successfully confined in the LbL film through electrostatic interactions. The cyclic voltammogram (CV) of ARS-confined PEI/CMC film-coated electrodes thus prepared exhibited redox waves in the potential range from -0.5 to -0.7 V originating from 9,10-anthraquinone moiety in ARS, demonstrating that ARS preserves its redox activity in the LbL film. An additional oxidation peak appeared around -0.4 V in the CV recorded in the solution containing phenylboronic acid (PBA), due to the formation of a boronate ester of ARS (ARS-PBA) in the film. The oxidation peak current at -0.4 V decreased upon addition of 3,4-dihydroxyphenylalanine (L-dopa) to the solution. Thus, the results suggest a potential use of the ARS-confined PEI/CMC films for constructing voltammetric sensors for L-dopa.

12.
Chem Commun (Camb) ; (41): 4312-4, 2006 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-17047851

RESUMO

Pseudorotaxane formed by reacting beta-cyclodextrin bearing a phenylboronic acid residue with 1-heptyl-4-(4'-dimethylaminostyryl)pyridinium functioned as a novel fluorescent saccharide receptor having unique responses.


Assuntos
Ácidos Borônicos/química , Fluorescência , Piridinas/química , Rotaxanos/química , Carcinógenos/química , Estrutura Molecular , Piridinas/síntese química , beta-Ciclodextrinas/química
13.
Anal Sci ; 22(5): 655-7, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16770039

RESUMO

Pyrene-appended alpha-cyclodextrin (3) in which a trimethylenediamine linker connected the pyrene residue to the alpha-cyclodextrin moiety showed pH-dependent fluorescence intensity changes. The fluorescence intensity was almost linearly changed within the pH range of 5 - 10. The unique fluorescence response of 3 to the pH was due not only to the favorable pK(a) values (pK(a1) = 6.4 and pK(a2) = 8.8), but also to the almost equal contributions of the amino groups to the pyrene's fluorescence quenching.


Assuntos
Corantes Fluorescentes/química , Pirenos/química , alfa-Ciclodextrinas/química , Diaminas/química , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética
14.
Anal Sci ; 22(2): 337-40, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16512435

RESUMO

With the help of nanocrystalline TiO2, the direct electrochemistry of xanthine oxidase (XOD) was achieved and two pairs of redox waves were observed. The interaction between XOD and nitric oxide (NO) was also investigated. The experimental results reveal that NO can be reduced at a XOD-nano TiO2 film modified electrode. When the NO concentration was low, the reduced product, HNO, would inactivate the protein. However, when the NO concentration was high, HNO would continue to react with NO to form N2O2- and N3O3-, which would not inhibit XOD, and thus the amount of active protein did not decrease any further.


Assuntos
Eletroquímica/métodos , Óxido Nítrico/química , Xantina Oxidase/química , Animais , Materiais Biocompatíveis/química , Técnicas de Química Analítica/métodos , Cristalização , Eletrodos , Elétrons , Heme/química , Concentração de Íons de Hidrogênio , Leite/metabolismo , Modelos Químicos , Nanopartículas , Titânio/química
15.
Anal Sci ; 21(4): 361-6, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15844326

RESUMO

Lipoylamino-beta- and gamma-cyclodextrin (LP-beta-CD and LP-gamma-CD, respectively) were adsorbed at the surface of gold electrodes by sulfur-gold bonding. The resultant electrodes exhibited quasi-reversible voltammograms for the redox reaction of Fe(CN)6(3-/4-) in aqueous solutions, with peak-to-peak separation (deltaEp) being 85 mV at 20 mV s(-1) as a potential sweep rate. When bile acids are added to the solution, deltaEp values increased to 200-300 mV with increasing the concentration of bile acids. A Langmuir-type adsorption analyses satisfactorily afforded the binding constants (Ksurf) of the surface-confined LP-beta-CD and LP-gamma-CD with the bile acids. The obtained Ksurf values of LP-gamma-CD are 5.0-50 times larger than the corresponding binding constants of gamma-CD in homogeneous aqueous solutions. Cyclic voltammetric experiments with positively, negatively, and non-charged adamantane derivatives as well as pH titration experiments revealed that the retardation of the electrode reaction of negatively charged Fe(CN)6(3-/4-) caused by bile acids was attributable (1) to electric potential changes due to the accumulation of the negative charges at the electrode surface, and (2) to an increase in the hydrophobicity of the electrode surface due to the binding of hydrophobic bile acids to the LP-beta-CD and LP-gamma-CD membranes.


Assuntos
Ácidos e Sais Biliares/análise , Ciclodextrinas/química , Algoritmos , Eletroquímica , Eletrodos , Ouro , Concentração de Íons de Hidrogênio , Cinética , Soluções
16.
Peptides ; 71: 202-10, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26238596

RESUMO

There is yet no firm experimental evidence that the evolutionary ancient gonadotropin-releasing hormone GnRH (i.e., GnRH1) also acts in invertebrate gametogenesis. The objective of this paper is to characterize candidate invGnRH peptides of Yesso scallop Patinopecten yessoensis (i.e., peptide identification, immunohistochemical localization, and immunoquantification) in order to reveal their bioactive form in bivalves. Using mass spectrometry (MS), we identified two invGnRH (py-GnRH) peptides from the scallop nerve ganglia: a precursor form of py-GnRH peptide (a non-amidated dodecapeptide; py-GnRH12aa-OH) and a mature py-GnRH peptide (an amidated undecapeptide; py-GnRH11aa-NH2). Immunohistochemical staining allowed the localization of both py-GnRH peptides in the neuronal cell bodies and fibers of the cerebral and pedal ganglia (CPG) and the visceral ganglion (VG). We found that the peptides showed a dimorphic distribution pattern. Notably, the broad distribution of mature py-GnRH in neuronal fibers elongating to peripheral organs suggests that it is multi-functional. Time-resolved fluorescent immunoassays (TR-FIA) enabled the quantification of each py-GnRH form in the single CPG or VG tissue obtained from one individual. In addition, we observed greater abundance of mature py-GnRH in VG compared with its level in CPG, suggesting that VG is the main producing organ of mature py-GnRH peptide and that py-GnRH may play a central regulatory role in neurons of scallops. Our study provides evidence, for the first time, for the presence of precursor and mature forms of invGnRH peptides in the nerve ganglia of an invertebrate.


Assuntos
Gânglios dos Invertebrados/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Oligopeptídeos/metabolismo , Pectinidae/metabolismo , Animais , Gânglios dos Invertebrados/química , Hormônio Liberador de Gonadotropina/química , Oligopeptídeos/química , Pectinidae/química
17.
Chem Commun (Camb) ; (2): 164-5, 2002 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-12120352

RESUMO

A beta-cyclodextrin dimer is found to be effective in preparing a layer-by-layer architecture of positively charged ferrocene-appended poly(allylamine) presumably on the basis of strong beta-cyclodextrin-ferrocene host-guest interaction.

18.
Anal Sci ; 28(2): 121-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22322803

RESUMO

A boronic acid fluorophore (C1-APB)/boronic acid-modified γ-cyclodextrin (3-PB-γ-CyD) complex as a supramolecular sensor has been designed for selective glucose recognition in water. The fluorescent response behavior of the C1-APB/3-PB-γ-CyD complex under various pH conditions revealed that a C1-APB/3-PB-γ-CyD complex solution containing glucose showed a large increase in the fluorescence intensity under alkaline pH conditions. In contrast, only small increases in the fluorescence intensity were noted for fructose and without sugar solutions. The observed response selectivity for the C1-APB/3-PB-γ-CyD complex was on the order of glucose >> galactose, mannose > fructose. The evidence on a large value of the inclusion constant (K(L·CyD) = 6.5 × 10(3) M(-1)), a marked broadening of the (1)H NMR spectra, and an enhancement of induced circular dichloism (ICD) intensity for the C1-APB/3-PB-γ-CyD complex by glucose binding supported the multi-point interaction of the C1-APB/3-PB-γ-CyD complex with glucose. These results demonstrated that the C1-APB/3-PB-γ-CyD complex functioned as an efficient supramolecular sensor for selective glucose recognition in water.


Assuntos
Ácidos Borônicos/química , Corantes Fluorescentes/química , Glucose/química , Água/química , gama-Ciclodextrinas/química , Glucose/análise , Concentração de Íons de Hidrogênio , Especificidade por Substrato
20.
Drugs Today (Barc) ; 45(5): 363-78, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19584965

RESUMO

Allopurinol is an inhibitor of xanthine oxidoreductase (XOR) and inhibits the generation of uric acid (UA) as the final product of purine catabolism, as well as the resulting generation of superoxide (O2(-)), in humans. Elevation of the serum UA (SUA) level, referred to as hyperuricemia (HU), eventually leads to gout and allopurinol has been used for the treatment of HU and gout. Studies have revealed the role of elevated SUA levels and the associated oxidative stress (OS) in a broad spectrum of pathological conditions and it is anticipated that these findings would also expand the use of allopurinol as a therapeutic drug. This article presents a review of reports, mainly of recent studies, on the efficacy of allopurinol in various diseases and explores novel potential uses of the drug. Important novel and potential uses of great interest include metabolic syndrome (MetS) and related disorders, chronic kidney disease (CKD), nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Ischemia-reperfusion injury and mucositis, encountered as adverse effects of cancer treatment, have also been under investigation as potential targets for allopurinol.


Assuntos
Alopurinol/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Xantina Desidrogenase/antagonistas & inibidores , Fígado Gorduroso/tratamento farmacológico , Humanos , Hepatopatias/dietoterapia , Mucosite/tratamento farmacológico , Insuficiência Renal Crônica/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Ácido Úrico/sangue , Xantina Desidrogenase/metabolismo
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