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1.
Dysphagia ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512436

RESUMO

Mastication is controlled by central pattern generator in the brainstem and can be modulated by volition. The aim of this study was to investigate the effect of chewing well on swallowing. Twenty-six healthy participants were instructed to eat 8, 12, and/or 16 g of steamed rice with barium sulphate under the following two conditions: chewing freely task (CF; chewing naturally in their usual manner) and chewing well task (CW; chewing the food with a request to "chew well"). We evaluated bolus transport and swallowing movement using videofluoroscopy and electromyography of the masseter, suprahyoid and thyrohyoid muscles. The chewing time and pharyngeal transit time (PTT) at the first swallow showed high reproducibility in both CF and CW. PTT for CW was significantly shorter and longer than CF in 12 and 16 g, respectively. In 12 g, CW increased the pharyngeal bolus velocity and decreased thyrohyoid EMG activity during swallowing compared with CF. In 16 g, the difference between CW and CF in the estimated swallowed bolus volume was positively correlated with that in upper esophageal sphincter transit duration. We speculate that CW modulates PTT during swallowing depending on the mouthful volume.

2.
Jpn J Ophthalmol ; 63(5): 417-424, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31183624

RESUMO

PURPOSE: We evaluated patient profiles, clinical features, associated systemic diseases, treatment modalities, and ocular complications in cases of scleritis and episcleritis. STUDY DESIGN: Retrospective. METHODS: Clinical data of 128 patients referred to the ophthalmology clinic at Jichi Medical University Hospital during the 4-year period from April 2011 to March 2015, and diagnosed with scleritis or episcleritis were examined. Gender, average onset age, unilateral or bilateral manifestation, classification type, associated systemic diseases, and treatments were retrospectively investigated. RESULTS: The cohort consisted of 57 men and 71 women. Average onset age was 54.3 ± 17.4 years. Diffuse anterior scleritis was the most common type. It was noted in 43 (32.8%) patients, followed by episcleritis in 35 (27.3%), nodular anterior scleritis in 23 (18.0%), necrotizing anterior scleritis in 22 (17.2%), and posterior scleritis in 6 (4.7%). Eighteen (81.8%) of 22 patients with necrotizing anterior scleritis required some type of systemic medication, including corticosteroid, cyclophosphamide, cyclosporine, azathioprine, methotrexate, or rituximab administration. Forty (31.3%) had associated systemic diseases, which included 10 with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis and 8 with rheumatoid arthritis (RA). Patients with ANCA-associated vasculitis had a tendency to develop scleritis first and had significantly worse visual prognoses compared to those with RA. CONCLUSIONS: Approximately 30% of the patients with scleritis and episcleritis had complications involving systemic diseases, including ten patients with ANCA-associated vasculitis and 8 with RA. ANCA-associated vasculitis was more often diagnosed after scleritis and patients suffered poorer visual prognoses than those with RA.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Artrite Reumatoide/complicações , Esclerite/etiologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Artrite Reumatoide/diagnóstico , Feminino , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Esclerite/classificação , Esclerite/epidemiologia
3.
Clin Ophthalmol ; 11: 1151-1156, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28670107

RESUMO

PURPOSE: To investigate uveitis incidence of new patients who visited Jichi Medical University Hospital, Tochigi, north of Tokyo, during 2011-2015, and to compare the results with previously reported data from other facilities. METHODS: We retrospectively analyzed clinical records of new patients with uveitis from April 2011 to March 2015 and compared the uveitis incidence with those from other hospitals. RESULTS: A total of 502 patients were enrolled in the study; definite diagnoses were made in 262 patients (52.2%). The top 4 diseases were sarcoidosis, 47 patients (9.4%); Vogt-Koyanagi-Harada (VKH) disease, 35 patients (7.0%); herpetic iritis, 29 patients (5.8%); and Behçet's disease, 21 patients (4.2%). CONCLUSION: The most commonly diagnosed diseases in our study were sarcoidosis, VKH disease, herpetic iritis, and Behçet's disease. Compared with the latest nationwide survey in Japan, our results showed similar trends.

4.
Methods Mol Biol ; 984: 45-50, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23386335

RESUMO

Reducing monosaccharides were derivatized with 2-aminobenzoic acid (2-AA) through reductive amination using sodium cyanoborohydride as a reductant, and the derivatives were separated by capillary zone electrophoresis with UV detection using 50 mM sodium phosphate (pH 5.5) or 150 mM sodium borate-50 mM sodium phosphate (pH 7.0) running buffer. The derivatives of monosaccharides, which are major components of various carbohydrate materials, were completely separated within 25 min.


Assuntos
Monossacarídeos/isolamento & purificação , ortoaminobenzoatos/química , Aminação , Boratos/química , Soluções Tampão , Eletroforese Capilar/métodos , Concentração de Íons de Hidrogênio , Monossacarídeos/síntese química , Oxirredução , Fosfatos/química
5.
ACS Appl Mater Interfaces ; 3(7): 2431-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21630639

RESUMO

We produced boron-mixed multi-walled carbon nanotube solids (B-mixed MWCNT solids) by heating and pressing the powder of purified MWCNTs mixed with 1, 5, and 10 wt % boron in the temperature range 1400-1800 °C every 200 °C under a constant pressure of 20 MPa in vacuo, and investigated the influence of boron addition on nanotube structure and the mechanical and electrical properties of the resulting B-mixed MWCNT solids. The structure of the prepared material was characterized by scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, high-resolution transmission electron microscopy-electron energy loss spectroscopy, Raman scattering spectroscopy, and X-ray diffraction, and their mechanical properties and conductivity were measured using a mechanical and Vickers indentation tester and an electric resistor, respectively. It is notable that part of the nanotubes in the B-mixed MWCNT solids solidified at 1800 °C had dramatically changed into rod-like graphitic carbons (RLGCs). The occupancy distribution of RLGCs increased with increasing boron contents. However, boron was not detected in the energy-loss near-edge structure spectrum of RLGCs. Furthermore, RLGCs were not observed in the boron-unmixed sample treated with the same solidified condition, indicating that adding boron causes a remarkable ability to transform the phase of MWCNT. Transformation from MWCNTs to RLGCs resulted in increased specific bending strength and modulus, Vickers hardness, and electrical conductivity of B-mixed MWCNT solids with increasing boron content and solidified temperature.

6.
Carbohydr Res ; 344(9): 1141-5, 2009 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-19376497

RESUMO

A complete separation with baseline resolution of the 2-AA derivatized saccharides, including mono-, di-, and oligosaccharides, was achieved using 50 mM sodium phosphate-150 mM borate solution, pH 7.0 as running buffer by capillary electrophoresis. It was thought to be a result of the inclusion of 150 mM borate in the running electrolyte solution. The formation of borate complexes was observed by means of (11)B and (13)C NMR spectroscopy and the electrophoretic mobilities of the various derivatives were calculated. It was found that steric factors play an important role in the stability of the formed borate complexes, which depends strongly on the configuration of the three vicinal hydroxyl groups at C-2, C-3, and C-4. 2-AA-Glc mainly forms stable 1,2-diester complexes with borate and 2-AA-Mal can form stable 1,2-monoesters. In turn, for 2-AA-Rib the formation of complexes is difficult to take place. The results implied that the configurational difference between the hydroxyl groups could cause the difference in formation of borate complexes leading to significant difference among saccharide molecules in their migration time on CE analysis.


Assuntos
Boratos/química , Carboidratos/química , Carboidratos/isolamento & purificação , Soluções Tampão , Eletroforese Capilar , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética
7.
ACS Nano ; 2(2): 348-56, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19206637

RESUMO

We produced large binder-free multi-walled carbon nanotube (MWNT) blocks from fluorinated MWNTs using thermal heating and a compressing method in vacuo. This technique resulted in the formation of covalent MWNT networks generated by the introduction of sp(3)-hybridized carbon atoms that cross-link between nanotubes upon de-fluorination. The resulting carbon nanotube blocks are lighter than graphite, can be machined and polished, and possess average bending strengths of 102.2 MPa, a bending modulus of 15.4 GPa, and an electrical conductivity of 2.1 x 10(2) S/cm. Although each nanotube exhibits a random structure in these blocks, the mechanical properties are 3 times higher than those obtained for commercial graphite. On the basis of theoretical molecular dynamics simulations, a model is presented for the nanotube interconnecting mechanism upon de-fluorination.


Assuntos
Cristalização/métodos , Eletroquímica/métodos , Flúor/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Reagentes de Ligações Cruzadas/química , Condutividade Elétrica , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
8.
Arch Microbiol ; 184(1): 56-65, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16052332

RESUMO

The photosynthetic bacterium Rhodobacter sphaeroides (R. sphaeroides) f. sp. denitrificans IL106 accumulates trehalose as the major organic osmoprotectant in response to a salt stress. An analysis of the R. sphaeroides 2.4.1 genome sequence revealed the presence of five different genes encoding enzymes belonging to three putative trehalose biosynthesis pathways (OtsA-OtsB, TreY-TreZ, and TreS). The function of the different pathways of trehalose was studied by characterizing strains defective in individual trehalose biosynthetic routes. A phenotypic comparison revealed that trehalose synthesis in R. sphaeroides f. sp. denitrificans IL106 is mediated mainly by the OtsA-OtsB pathway and, to some extent, by the TreY-TreZ pathway. Strains with the simultaneous inactivation of these two pathways were completely unable to synthesize trehalose. On the other hand, treS mutants showed an increase in the trehalose level. These results suggest that treS plays a role in trehalose degradation. In addition, treS was found to be important in reducing trehalose after osmotic stress was removed. In this report, we show that the strains that accumulate the most trehalose adapt to salt stress earlier. This is the first report of an organism using multiple pathways to synthesize trehalose solely for use as a compatible solute against salt stress.


Assuntos
Adaptação Fisiológica , Rhodobacter sphaeroides/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Trealose/biossíntese , Regulação Bacteriana da Expressão Gênica , Concentração Osmolar , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/metabolismo , Trealose/química
9.
Anal Chem ; 77(10): 3309-14, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15889923

RESUMO

This article describes an antiallergic drug-screening system by the detection of histamine released from mast cells (suspension cells) on a multilayer microchip. In this study, the elastmeric material, poly(dimethylsiloxane) (PDMS), was employed to fabricate microchannels and microchambers. The microchip consists of two sections: a histamine-releasing one, which has a cell chamber, and a histamine-derivatizing one. Both were laminated to one microchip. Rat peritoneal mast cells were retained in the cell chamber (1.2 microL) with a filtering system using a cellulose nitrate membrane. This filtering system could easily retain suspension cells without cell damage. Mast cells were viable for a sufficient time to conduct the assay on the cell chamber. The cells were stimulated with a chemical release compound 48/80 (C48/80), and then histamine flowed into the lower layer, where it was derivatized to the fluorescent molecules with o-phthalaldehyde and its fluorescence was detected on the microchip. This flow system could detect the time course of the histamine release, and this microchip system required only 20 min for the assay. By this integrated system, 51 pmol of histamine released from 500 cells was detected, and the number of cells required for the assay was reduced to 1% compared with conventional bulk systems. By comparing the released histamine levels with and without drugs, their effect could be evaluated. The inhibition ratio of C48/80 induced-histamine release using an antiallergic drug, disodium cromoglicate (DSCG), was related to the concentration of DSCG. This flow system was applicable for antiallergy drug screening by rapid measurement of the inhibition of histamine release from a very small amount of mast cells.


Assuntos
Antialérgicos/análise , Bioensaio/métodos , Dimetilpolisiloxanos/química , Liberação de Histamina , Histamina/análise , Técnicas Analíticas Microfluídicas/métodos , Animais , Antialérgicos/farmacologia , Bioensaio/instrumentação , Células Cultivadas , Fluorescência , Mastócitos/metabolismo , Microquímica , Técnicas Analíticas Microfluídicas/instrumentação , Ratos , Fatores de Tempo , o-Ftalaldeído/química
10.
Anal Sci ; 21(1): 21-4, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15675510

RESUMO

A capillary electrophoresis method was developed for the analysis of oligosaccharides combined with derivatization with 2-aminobenzoic acid. Glycosaminoglycan delta-disaccharides were effectively resolved on a fused-silica capillary tube using 150 mM borate, pH 8.5, as a running electrolyte solution. This analytical method was applied to the identification of glycosaminoglycan in combination with enzymatic digestion. The separation of N-glycans or glucose-oligomers was performed with a phosphate buffer containing polyethylene glycol or borate as an electrolyte solution. This method is expected to be useful in the determination of oligosaccharide structures in a glycoprotein.


Assuntos
Eletroforese Capilar/métodos , Glicosaminoglicanos/isolamento & purificação , Polissacarídeos/isolamento & purificação , Animais , Asparagina , Condroitina ABC Liase/metabolismo , Dissacarídeos/análise , Dissacarídeos/isolamento & purificação , Glicosaminoglicanos/metabolismo , Oligossacarídeos/análise , Oligossacarídeos/isolamento & purificação , Peptídeo Hidrolases/metabolismo , Polissacarídeos/metabolismo , ortoaminobenzoatos
11.
Talanta ; 66(1): 244-8, 2005 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-18969988

RESUMO

A simple and high-resolution analytical method for the determination of dimethylsulfoniopropionate (DMSP) in sugarcane and marine algae is described. Effective extraction of DMSP from plant samples was also investigated using organic solvents, 5% perchloric acid or deionised water. To increase the sensitivity, DMSP in the extracts was first converted to a phenacyl ester, and the reaction mixture was applied directly to capillary electrophoresis without any pretreatment. Water extraction followed by esterification in a pH 4 reaction buffer was found most suitable for the measurement of alkaline-labile DMSP. This method was applied to the determination of DMSP levels in marine algae samples collected from the seashore of Nagasaki, Japan. An increase in DMSP content in Ulva pertusa in the winter period was observed.

12.
Anal Sci ; 20(1): 209-12, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14753285

RESUMO

On-chip fluorescence determination of sulfite and nitrite with N-(9-acridinyl)maleimide (NAM) and 2,3-diaminonaphthalene (DAN) has been developed using a novel fluorescence detection unit for microchip analysis. Usually, these fluorescence reagents are derivatized and detected separately in microchip analysis because different fluorescence wavelengths are emitted. The proposed fluorescence detection unit has optical fibers with no optical filter, and plural wavelengths of fluorescence were detected sensitively, even in the microchip. In this study, the simultaneous determination of sulfite and nitrite in environmental samples was performed with a polymer microchip analysis system. The calibration curves of sulfite and nitrite showed linear relations (R2 = 0.998 (sulfite) and R2 = 0.990 (nitrite)), and the relative standard deviations (RSD) for 4 runs were 2.1% (20 microM sulfite) and 1.3% (20 microM nitrite), respectively. The proposed method was applied to the recovery test of sulfite and nitrite in environmental samples.

13.
Anal Sci ; 20(1): 223-5, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14753288

RESUMO

An analytical method for dimethyl sulfoxide (DMSO) in aqueous samples at nanomolar levels has been improved. DMSO was reduced to dimethyl sulfide (DMS), concentrated on an adsorbent, and measured by gas chromatography. In the presence of iron chloride, the sodium borohydride (NaBH4) reduction of DMSO proceeded smoothly and efficiently, and the repeatability of this reaction was significantly improved. The detection limit was 0.27 nM for DMSO, and its repeatability of the peak-area measurement was 4.1% as RSD (n = 5).


Assuntos
Cromatografia Gasosa/métodos , Dimetil Sulfóxido/análise , Poluentes Químicos da Água/análise , Cromatografia Gasosa/normas
14.
Analyst ; 128(6): 724-7, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12866895

RESUMO

A mediator immobilized dimethyl sulfoxide (DMSO) sensor using DMSO reductase (DMSO-R) was constructed. Methyl viologen (MV) was used as a mediator and immobilized on a glassy carbon (GC) electrode with Nafion polymer. DMSO-R from Rhodobacter sphaeroides f. sp. denitrificans was retained by a dialysis film on the modified GC electrode. The amperometric signal in response to DMSO was observed. The linear range of the calibration curve for DMSO was between 0 and 600 microM. The response time was within 100 s and the relative standard deviation was 4% at 200 microM DMSO (n = 4). To eliminate the background noise derived from oxygen in samples, the glucose oxidase-catalase retained DMSO sensor was also examined.


Assuntos
Técnicas Biossensoriais , Dimetil Sulfóxido , Eletrodos , Enzimas
15.
Anal Sci ; 19(6): 933-6, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12834238

RESUMO

The 1H-magnetic resonance imaging technique was applied for monitoring the extent of the heat coagulation in the shell egg. It is demonstrated that spin-spin relaxation time (T2) is an effective marker to observe the extent of coagulation in egg white and yolk and that the T2 value image is quite useful to recognize non-destructively the extent and status of coagulation of the heated eggs. This technique can also be applied to the material science as well as food science for observation of the inner status of the objects.


Assuntos
Óvulo/química , Codorniz/metabolismo , Animais , Casca de Ovo/química , Clara de Ovo/análise , Gema de Ovo/química , Temperatura Alta , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Água/análise
16.
Biosens Bioelectron ; 18(5-6): 735-9, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12706586

RESUMO

An amperometric dimethyl sulfoxide (DMSO) sensor was constructed based on DMSO reductase (DMSO-R). DMSO-R from Rhodobacter sphaeroides f. sp. denitrificans was immobilized by BSA-glutaraldehyde cross-linking at the surface of a glassy carbon electrode. Mediators were added to the sample solution in a free form. Several mediators (methyl viologen (MV), benzyl viologen (BV), neutral red (NR), safranin T (ST), FMN, phenazine methosulfate (PMS)), which can donate electrons to DMSO-R, were examined with the DMSO-R immobilized electrode. Among them MV was selected as a model mediator because of its wide linear response range and fast response time. The response current was effected by the measurement temperature but hardly effected by the pH of the sample solution. The response current was increased with the measurement temperature up to 50 degrees C. A response current was observed at 1 microM DMSO and the response time was 20 s under the optimum conditions. The response was observed for approximately 2 weeks. By the reduction of Schiff base in the cross-linking layer the response range became narrower but most of the response current was retained at 300 microM of DMSO for more than 5 weeks.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Dimetil Sulfóxido/análise , Eletroquímica/instrumentação , Enzimas Imobilizadas/química , Proteínas Ferro-Enxofre , Oxirredutases/química , Coenzimas/química , Dimetil Sulfóxido/química , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Concentração de Íons de Hidrogênio , Oxirredutases/biossíntese , Rhodobacter sphaeroides/química , Rhodobacter sphaeroides/enzimologia , Temperatura
17.
Anal Biochem ; 314(1): 128-34, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12633611

RESUMO

Saccharides including mono- and disaccharides were quantitatively derivatized with 2-aminobenzoic acid (2-AA). These derivatives were then separated by capillary zone electrophoresis with UV detection using 50mM sodium phosphate buffer as the running electrolyte solution. In particular, the saccharide derivatives with the same molecular weight as 2-AA aldohexoses (mannose and glucose) and 2-AA aldopentoses (ribose and xylose) were well separated. The underlying reasons for separation were explored by studying their structural data using 1H and 13C NMR. It was found that the configurational difference between their hydroxyl group at C2 or C3 could cause the difference in Stokes' radii between their molecules and thus lead to different electrophoretic mobilities. The correlation between the electrophoretic behavior of these carbohydrate derivatives and their structures was studied utilizing the calculated molecular models of the 2-AA-labeled mannose, glucose, ribose, and xylose.


Assuntos
Eletroforese Capilar/métodos , Monossacarídeos/química , Monossacarídeos/isolamento & purificação , ortoaminobenzoatos/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Coloração e Rotulagem , Relação Estrutura-Atividade
18.
Phytochem Anal ; 13(4): 189-94, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12184170

RESUMO

In recent years the role of betaines in higher plants has been extensively investigated in relation to environmental stress response. This paper reports the establishment of a simple, rapid and reliable method for the determination of betaines using capillary electrophoresis (CE) at low pH. Betaines were first converted to their phenacyl esters and the crude reaction mixture was then applied directly to CE without any pre-treatment. Employing an electrolyte running solution at pH 3 gave a well-resolved electropherogram for the esters of glycine betaine (1), trigonelline, proline betaine, gamma-butyro betaine, and carnitine. The content of 1 and its variation in plant samples collected from high-salinity areas in north China and west Australia are presented.


Assuntos
Betaína/química , Chenopodiaceae/química , Eletroforese Capilar/métodos , Concentração de Íons de Hidrogênio , Spinacia oleracea/química , Ziziphus/química , Reprodutibilidade dos Testes
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