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1.
Phys Rev Lett ; 117(19): 195901, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27858436

RESUMO

Heat conduction possesses (thermal) modes in analogy with acoustics even without oscillation. Here, we establish thermal mode spectroscopy to measure the thermal diffusivity of small specimens. Local heating with a light pulse excites such modes that show antinodes at the heating point, and photothermal detection at another antinode spot allows measuring relaxation behavior of the desired mode selectively: The relaxation time yields thermal diffusivity. The Ritz method is proposed for arbitrary geometry specimens. This method is applicable even to a diamond crystal with ∼1 mm dimensions.

2.
Telemed J E Health ; 18(4): 292-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22400972

RESUMO

Smartphones are very common devices in daily life that have a built-in tri-axial accelerometer. Similar to previously developed accelerometers, smartphones can be used to assess gait patterns. However, few gait analyses have been performed using smartphones, and their reliability and validity have not been evaluated yet. The purpose of this study was to evaluate the reliability and validity of a smartphone accelerometer. Thirty healthy young adults participated in this study. They walked 20 m at their preferred speeds, and their trunk accelerations were measured using a smartphone and a tri-axial accelerometer that was secured over the L3 spinous process. We developed a gait analysis application and installed it in the smartphone to measure the acceleration. After signal processing, we calculated the gait parameters of each measurement terminal: peak frequency (PF), root mean square (RMS), autocorrelation peak (AC), and coefficient of variance (CV) of the acceleration peak intervals. Remarkable consistency was observed in the test-retest reliability of all the gait parameter results obtained by the smartphone (p<0.001). All the gait parameter results obtained by the smartphone showed statistically significant and considerable correlations with the same parameter results obtained by the tri-axial accelerometer (PF r=0.99, RMS r=0.89, AC r=0.85, CV r=0.82; p<0.01). Our study indicates that the smartphone with gait analysis application used in this study has the capacity to quantify gait parameters with a degree of accuracy that is comparable to that of the tri-axial accelerometer.


Assuntos
Aceleração , Marcha , Telemedicina/instrumentação , Adolescente , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Japão , Masculino , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Telemedicina/métodos , Adulto Jovem
3.
Rheumatol Int ; 32(12): 3869-74, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22193221

RESUMO

A disturbance in gait pattern is a serious problem in patients with rheumatoid arthritis (RA). The aim of the present study was to examine the utility of the smartphone gait analysis application in patients with RA. The smartphone gait analysis application was used to assess 39 patients with RA (age 65.9 ± 10.0 years, disease duration 11.9 ± 9.4 years) and age-matched control individuals (mean age, 69.1 ± 5.8 years). For all RA patients, the following data were obtained: disease activity score (DAS) 28, modified health assessment questionnaire (mHAQ), and assessment of walking ability. Patients walked 20 m at their preferred speed, and trunk acceleration was measured using a Smartphone. After signal processing, we calculated the following gait parameters for each measurement terminal: peak frequency (PF), autocorrelation peak (AC), and coefficient of variance (CV) of the acceleration peak intervals. The gait parameters of RA and control groups were compared to examine the comparability of the 2 groups. Criterion-related validity was determined by evaluating the correlation between gait parameters and clinical parameters using Spearman's correlation coefficient. The RA group showed significantly lower scores for the walking speed, AC, and CV than the control group. There were no significant differences in PF. PF (gait cycle) was mildly associated with gait speed (P < 0.05). AC (gait balance) was moderately associated with the DAS, mHAQ, gait ability, and gait speed (P < 0.05). CV (gait variability) was moderately associated with the DAS, gait ability, and gait speed (P < 0.05). This is the first study to examine the use of a smartphone device for gait pattern measurement. The results suggest that some gait parameters recorded using the smartphone represent an acceptable assessment tool for gait in patients with RA.


Assuntos
Artrite Reumatoide/fisiopatologia , Telefone Celular , Marcha/fisiologia , Transtornos dos Movimentos/diagnóstico , Caminhada/fisiologia , Idoso , Artrite Reumatoide/complicações , Fenômenos Biomecânicos/fisiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/complicações , Transtornos dos Movimentos/fisiopatologia
4.
J Biosci Bioeng ; 111(1): 104-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20869309

RESUMO

Alterations in D-amino acid concentrations and microbial community structures during the fermentation of red and white wines were analyzed to clarify the relationship between the occurrence of d-amino acids and the actions of fermentative microorganisms. Relatives of Saccharomyces cerevisiae and Oenococcus oeni were detected in red wine samples, and relatives of S. cerevisiae, O. oeni, and Gluconacetobacter saccharivorans were detected in white wine samples. The S. cerevisiae relatives were detected throughout the fermentation process, whereas the O. oeni relatives were detected at the late stage of fermentation in both the red and white wine samples. The G. saccharivorans relative was detected in the early stage of fermentation. The amino acid analysis showed that D-alanine, D-glutamic acid, and D-lysine were present in both the red and white wine samples. The concentrations of these D-amino acids increased as the fermentation continued, especially from the malolactic fermentation stage to the end of the fermentation processes. These increases seem to be linked to the presence of O. oeni relatives.


Assuntos
Aminoácidos/análise , Fermentação , Microbiologia de Alimentos , Vinho/microbiologia , Gluconacetobacter/isolamento & purificação , Oenococcus/isolamento & purificação , Saccharomyces cerevisiae/isolamento & purificação
5.
Biomed Res ; 26(4): 179-85, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16152734

RESUMO

We have evaluated the effect of natural human interferon (IFN)-alpha on the growth of chlamydia trachomatis in human epithelial cells in vitro and revealed that IFN-alpha has reduced both growth and infectivity of C. trachomatis. The effect of IFN-alpha was reversed by the addition of exogenous L-tryptophan and iron to the culture medium, suggesting that antichlamydial effect of IFN-alpha was caused by depletion of intracellular tryptophan and iron, both of which are essential for chlamydial growth. When IFN-alpha was combined with another antichlamydial cytokines, IFN-gamma and tumor necrosis factor (TNF)-alpha, the effect was synergistically enhanced. Therefore, IFN-alpha would act coordinately with other cytokines such as IFN-gamma and TNF-alpha, and play an important role in host defense against infection and in the establishment of persistent chlamydial infection of host, in which the organism remains viable, but in a culture-negative state.


Assuntos
Antineoplásicos/farmacologia , Infecções por Chlamydia/metabolismo , Chlamydia trachomatis/crescimento & desenvolvimento , Interferon-alfa/farmacologia , Interferon gama/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Antineoplásicos/imunologia , Infecções por Chlamydia/imunologia , Chlamydia trachomatis/imunologia , Sinergismo Farmacológico , Células HeLa , Humanos , Interferon-alfa/imunologia , Interferon gama/imunologia , Fator de Necrose Tumoral alfa/imunologia
6.
Biosci Biotechnol Biochem ; 68(4): 881-7, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15118318

RESUMO

The immuno-potentiating effects of the antler-shaped fruiting body of Ganoderma lucidum (Rokkaku-Reishi, RR), which has been used as a traditional supplement for human health, were investigated in mice. BALB/c mice were administered orally with RR for 3 days at a dose of 50 mg/kg or 500 mg/kg, and interferon-gamma (IFN-gamma) production by splenocytes in response to lipopolysaccharide (LPS) was examined on day 4. The oral administration of 500 mg/kg of RR resulted in a significant increase (p<0.05) in IFN-gamma production. Stimulation of splenic adherent cells from these mice with LPS also resulted in a significant increase (p<0.05) in interleukin-12 (IL-12) production compared with that from the control mice, suggesting that splenic macrophages were activated by RR administration. Furthermore, 500 mg/kg of RR administered for 14 days resulted in a significant increase (p<0.05) in IFN-gamma production by splenocytes in response to both LPS and concanavalin A (Con A). These results suggest that not only splenic macrophages but also T cells were activated by the long-term treatment with RR in vivo. On the other hand, the production of interleukin-4 (IL-4), which is known as an allergic disease-related cytokine, was not affected by the long-term treatment with RR. Our results suggest that the oral administration of RR resulted in Th1-associated immuno-potentiating activities in vivo.


Assuntos
Imunidade/efeitos dos fármacos , Imunidade/imunologia , Extratos Vegetais/farmacologia , Reishi/química , Reishi/crescimento & desenvolvimento , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Células Cultivadas , Concanavalina A/farmacologia , Feminino , Glucanos/metabolismo , Interferon gama/biossíntese , Interferon gama/imunologia , Interleucina-12/biossíntese , Interleucina-12/imunologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/administração & dosagem , Baço/efeitos dos fármacos , Baço/imunologia , Baço/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Fatores de Tempo
7.
Biol Pharm Bull ; 25(8): 1018-21, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12186401

RESUMO

Lumin was orally administered to mice daily for 3 d, and on the day following the final administration, mice were sacrificed and splenocytes were stimulated with lipopolysaccharide (LPS). Splenocytes obtained from lumin-treated mice showed enhanced production of interferon gamma (IFN-gamma) and increased percentages of CD3+ cells. Although T cells are considered to be the source of IFN-gamma, it is unlikely that LPS directly stimulates T cells. Next we performed neutralization experiments using a monoclonal antibody (mAb) against interleukin (IL-)12 because this cytokine, which is produced by macrophages, has the direct ability to induce IFN-gamma production and the proliferation of activated T cells. This antibody inhibited IFN-gamma production by splenocytes. We thus show that orally administered lumin enhances IFN-gamma production by splenocytes when the latter are stimulated with LPS, a phenomenon that was observed in correlation with activation of T cells by IL-12, that is produced by macrophages.


Assuntos
Interferon gama/biossíntese , Interleucina-12/fisiologia , Lipopolissacarídeos/farmacologia , Compostos de Quinolínio/farmacologia , Baço/efeitos dos fármacos , Animais , Sinergismo Farmacológico , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Baço/citologia , Baço/metabolismo
8.
Int Immunopharmacol ; 2(4): 565-78, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11962735

RESUMO

The therapeutic effects of tryptanthrin (TRYP), a natural product from the medicinal plant Polygonum tinctorium, were examined in a murine model of inflammatory bowel disease (IBD). Colitis was induced by 5% dextran sodium sulfate (DSS) in drinking water for 7 days from day 0. TRYP (100 mg/kg) was administered orally suspended in 5% arabia gum everyday from day 3 for 5 days. Histopathological analysis showed reduced colon damage in TRYP-treated mice on day 6; however, colon injury resumed after treatment was stopped. The production of prostaglandin E2 (PGE2), tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) by untreated and treated mouse colon tissues cultured in vitro were mostly unchanged by TRYP treatment. However, mitogen-stimulated spleen cells from TRYP-treated colitic mice produced less interleukin 2 (IL-2) and less interferon-gamma (IFN-gamma) than untreated colitic mouse spleen cells, early after induction of colitis. When colitis was induced with 5% DSS for 7 days and TRYP was given to the mice for 8 days from day 3, TRYP enhanced the survival of the mice but results were not significant. A significant reduction of weight loss was observed in TRYP-treated mice with colitis induced by 5% DSS for 4 days as compared to control mice. Remarkably, whereas 90% of the vehicle-treated mice died from wasting disease, all the TRYP-treated mice survived, suggesting that TRYP may have a therapeutic effect on colitis.


Assuntos
Colite/induzido quimicamente , Colite/tratamento farmacológico , Sulfato de Dextrana/farmacologia , Fitoterapia , Quinazolinas/uso terapêutico , Animais , Fatores Biológicos/uso terapêutico , Colite/metabolismo , Colite/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Citocinas/biossíntese , Dinoprostona/metabolismo , Medicamentos de Ervas Chinesas , Feminino , Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Mitógenos/imunologia , Óxido Nítrico/metabolismo , Polygonum/química , Baço/citologia , Baço/imunologia , Fatores de Tempo
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