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1.
Food Funct ; 14(3): 1796, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36655723

RESUMO

Correction for 'Curcumol inhibits breast cancer growth via NCL/ERα36 and the PI3K/AKT pathway' by Zhou Lu Wei et al., Food Funct., 2023, https://doi.org/10.1039/d2fo02387c.

2.
Chin J Nat Med ; 13(4): 316-20, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25908632

RESUMO

It has been reported that hyperspectral data could be employed to qualitatively elucidate the spatial composition of tablets of Chinese medicinal plants. To gain more insights into this technology, a quantitative profile provided by near infrared (NIR) spectromicroscopy was further studied by determining the glycyrrhizic acid content in licorice, Glycyrrhiza uralensis. Thirty-nine samples from twenty-four different origins were analyzed using NIR spectromicroscopy. Partial least squares, interval partial least square (iPLS), and least squares support vector regression (LS-SVR) methods were used to develop linear and non-linear calibration models, with optimal calibration parameters (number of interval numbers, kernel parameter, etc.) being explored. The root mean square error of prediction (RMSEP) and the coefficient of determination (R(2)) of the iPLS model were 0.717 7% and 0.936 1 in the prediction set, respectively. The RMSEP and R(2) of LS-SVR model were 0.515 5% and 0.951 4 in the prediction set, respectively. These results demonstrated that the glycyrrhizic acid content in licorice could barely be analyzed by NIR spectromicroscopy, suggesting that good quality quantitative data are difficult to obtain from microscopic NIR spectra for complicated Chinese medicinal plant materials.


Assuntos
Glycyrrhiza/química , Ácido Glicirrízico/análise , Microscopia/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Medicamentos de Ervas Chinesas/química , Análise dos Mínimos Quadrados
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2391-6, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25532332

RESUMO

The present paper firstly reviewed the research progress and main methods of NIR spectral assignment coupled with our research results. Principal component analysis was focused on characteristic signal extraction to reflect spectral differences. Partial least squares method was concerned with variable selection to discover characteristic absorption band. Two-dimensional correlation spectroscopy was mainly adopted for spectral assignment. Autocorrelation peaks were obtained from spectral changes, which were disturbed by external factors, such as concentration, temperature and pressure. Density functional theory was used to calculate energy from substance structure to establish the relationship between molecular energy and spectra change. Based on the above reviewed method, taking a NIR spectral assignment of chlorogenic acid as example, a reliable spectral assignment for critical quality attributes of Chinese materia medica (CMM) was established using deuterium technology and spectral variable selection. The result demonstrated the assignment consistency according to spectral features of different concentrations of chlorogenic acid and variable selection region of online NIR model in extract process. Although spectral assignment was initial using an active pharmaceutical ingredient, it is meaningful to look forward to the futurity of the complex components in CMM. Therefore, it provided methodology for NIR spectral assignment of critical quality attributes in CMM.


Assuntos
Medicamentos de Ervas Chinesas/normas , Materia Medica/normas , Espectroscopia de Luz Próxima ao Infravermelho , Ácido Clorogênico , Medicamentos de Ervas Chinesas/análise , Análise dos Mínimos Quadrados , Materia Medica/análise , Análise de Componente Principal
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(10): 2821-6, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25739232

RESUMO

The optimization method was established to investigate the effect of near infrared chemical imaging (NIR-CI) detection parameters on hyperspectral data quality. In order to optimize the detection parameters, chlorpheniramine maleate (CPM) tablets were chosen as examples and the L9(3(4)) orthogonal-test design was adopted to research the effects of spectral resolution, spatial resolution, scan times and scan height. Binary image coupled with statistical measurement was proposed to quantitatively analyze hyperspectral data and determine the content of CPM on the tablet surface. High-performance liquid chromatography (HPLC) was used as reference method for accurate CPM determination. The absolute value of the difference between CPM con- tents obtained from NIR-CI and HPLC was chosen as index. The result demonstrated that the optimum parameters for acquiring hyperspectral data were: 25 µm x 25 µm (spatial resolution), 5340 (scan height, the value of Z, precise focus), 16 cm(-1) (spectral resolution) and 16 (scan times). The influence of scan height on hyperspectral data was firstly investigated. The optimized parameters could be applied to CPM tablets and other drugs for NIR-CI data acquisition and methodology establishment.


Assuntos
Clorfeniramina/análise , Cromatografia Líquida de Alta Pressão , Espectroscopia de Luz Próxima ao Infravermelho , Comprimidos
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(9): 2363-8, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24369632

RESUMO

Multivariate detection limits (MDLs) of different types of near-infrared instruments were investigated to guide the selection of device type for TCM NIR analysis. In this paper, near-infrared spectroscopy of Qingkailing injection was performed in transmission mode on four near-infrared spectrometers named a, b, c and d, respectively. High performance liquid chromatography (HPLC) was used as the reference method to determine the content of baicalin in Qingkailing injection. Partial least squares (PLS) and interval partial least squares (iPLS) quantitative models of baicalin in Qingkailing injection were established and MDLs of quantitative models based on different types of instruments were calculated. The determination coefficient of prediction (R2(pre))and the root mean square errors of prediction (SEP) of PLS models of four different near-infrared spectrometers are 0.9762 and 230.4 microg x mL(-1) (a), 0.9561 and 246.4 microg x mL(-1) (b), 0.9662 and 264.4 microg x mL*-1) (c), 0.9985 and 71.5 microg x mL(-1) (d). And the model of instrument d shows a better prediction performance than the other three types. There are no remarkable superiorities in predictability in iPLS models of instruments a and b after variable selection, since the R2(pre) and SEP values for instruments a and b are 0.9771 and 218.4 microg x mL(-1), and 0.9754 and 219.4 microg x mL(-1), respectively. Models c and d show no results of variable selection. MDLs (delta(0.05, 0.05) of different instruments are all less than 250 microg x mL(-1), and the MDLs of instruments c and d reach to 58 and 2.9 microg x mL(-1) respectively. The results reveal that the predictability of models and corresponding MDLs are different for different detection equipments. This paper innovatively used the theory of MDL to investigate the detection performance of different types of NIR instruments. The results demonstrated the feasibility of the approach. And it is expected that in actual applications, choosing the right type of instrument should be based on the characteristics of the study carrier to ensure quantitative accuracy.


Assuntos
Medicamentos de Ervas Chinesas/análise , Flavonoides/análise , Espectroscopia de Luz Próxima ao Infravermelho , Cromatografia Líquida de Alta Pressão , Injeções , Análise dos Mínimos Quadrados , Limite de Detecção , Modelos Teóricos
6.
Lasers Surg Med ; 42(6): 503-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20662027

RESUMO

BACKGROUND: The low power laser irradiation (LPLI) can promote the wound healing, but the mechanism is still not fully understood. We have found in our previous work that the LPLI induces mast cells to release the histamine and thus suggested that the increased histamine release is probably one of the causes for promoting the wound healing since mast cells have been found to play positive roles in the process of wound healing. This study aims to explore the mechanism of histamine release in RBL-2H3 mast cells under laser irradiations. MATERIALS AND METHODS: The wavelength effect of laser irradiations, the permeability function of mitochondrial membrane, the Bcl-2 effect, the cytosolic alkalinization and the increment of intracellular Ca(2+) ([Ca(2+)](i)), on histamine release in RBL-2H3 cells were studied, respectively, with the corresponding fluorescence probes. RESULTS: The action bands of laser irradiations were consistent with the absorption bands of cytochrome c oxidase, suggesting that cytochrome c oxidase is the photoacceptor. After laser irradiation, (1) the cytochrome c releases from mitochondrial to cytosol reflecting an increased permeability of mitochondrial membrane, (2) the cytosolic alkalinization appears, (3) [Ca(2+)](i) increases, and (4) finally the enhancement of histamine release occurs. When Bcl-2 was used to inhibit the permeability of mitochondrial membrane these cellular signaling from (1) to (4) were all suppressed obviously. CONCLUSION: As a photoacceptor, cytochrome c oxidase absorbs incident photons and initiates the mitochondrial signaling. When the signals are transferred from the mitochondrial to the cytosol, the cytosolic alkalinization appears leading to the opening of a Ca(2+) channel on the membrane, the transient receptor potential vanilloid (TRPV), and an increment of [Ca(2+)](i). The increased [Ca(2+)](i) consequently mediates an enhanced histamine release. Such a responding chain is a suggested mechanism to understand the histamine release in RBL-2H3 cells under laser irradiations.


Assuntos
Cálcio/metabolismo , Liberação de Histamina/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Mastócitos/efeitos da radiação , Mitocôndrias/efeitos da radiação , Animais , Sinalização do Cálcio , Linhagem Celular Tumoral , Citosol/química , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Concentração de Íons de Hidrogênio , Mastócitos/metabolismo , Mitocôndrias/metabolismo , Permeabilidade/efeitos da radiação , Ratos
7.
Ultrastruct Pathol ; 32(5): 193-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18958792

RESUMO

Although the spatial and temporal distributions of cellular NAD(P)H concentrations have been theoretically predicted as typical patterns of the metabolism in living cells, so far such a pattern was observed only in neutrophils. In this work, the dynamic NAD(P)H distributions in rat basophilic leukemia (RBL-2H3) and human hepatocellular carcinoma (Hep G2) cells were studied by imaging the autofluorescence of cellular NAD(P)H with a sensitive CCD detector in a confocal microscope. The typical pattern of the cytoplasmic NAD(P)H wave traveling along the long axis of the elongated cell with a velocity of 2.2+/-0.6 mircom/s was detected in RBL-2H3 cells. While in the case of Hep G2 cells, only the oscillation of the mitochondrial NAD(P)H was observed because the NAD(P)H mainly localized in mitochondria of Hep G2 cells. These results confirm the metabolic pattern of NAD(P)H in living cells and suggest that the expression of the metabolic pattern probably differs in different cell lines.


Assuntos
Carcinoma Hepatocelular/metabolismo , Leucemia Basofílica Aguda/metabolismo , Neoplasias Hepáticas/metabolismo , Microscopia Confocal , NADP/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Citoplasma/metabolismo , Humanos , Leucemia Basofílica Aguda/patologia , Neoplasias Hepáticas/patologia , Mitocôndrias/metabolismo , Ratos , Fatores de Tempo
8.
J Biomed Opt ; 13(2): 020503, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18465946

RESUMO

To develop an accurate and convenient method for measuring the heart rate of zebra fish in vivo, a system combining fast differential interference contrast (DIC) imaging with an autocorrelation technique is established. The imaging correlation coefficient corr(i,j) between frame i, selected from the obtained time-lapse imaging series as the reference image, and any other frame j, is calculated as the time-dependent cycle course. Heat rate is determined by the cycle period of the corr with a high temporal resolution of 4 ms, achieved by fast charge-coupled device (CCD) imaging of 250 frames per second. With this high-resolution system, we find that 1-mgL cadmium not only induces the slowing of the heart rate, but also caused signs of arrhythmia in treated fish.


Assuntos
Algoritmos , Cardiotocografia/métodos , Frequência Cardíaca/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Microscopia de Contraste de Fase/métodos , Peixe-Zebra/embriologia , Peixe-Zebra/fisiologia , Animais , Estatística como Assunto
9.
Photochem Photobiol ; 83(4): 979-84, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17645673

RESUMO

Although laser irradiation has been reported to promote skin wound healing, the mechanism is still unclear. As mast cells are found to accumulate at the site of skin wounds we hypothesized that mast cells might be involved in the biological effects of laser irradiation. In this work the mast cells, RBL-2H3, were used in vitro to investigate the effects of laser irradiation on cellular responses. After laser irradiation, the amount of intracellular calcium ([Ca2+]i) was increased, followed by histamine release, as measured by confocal fluorescence microscopy with Fluo-3/AM staining and a fluorescence spectrometer with o-phthalaldehyde staining, respectively. The histamine release was mediated by the increment of [Ca2+]i from the influx of the extracellular buffer solution through the cation channel protein, transient receptor potential vanilloid 4 (TRPV4). The TRPV4 inhibitor, Ruthenium Red (RR) can effectively block such histamine release, indicating that TRPV4 was the key factor responding to laser irradiation. These induced responses of mast cells may provide an explanation for the biological effects of laser irradiation on promoting wound healing, as histamine is known to have multi-functions on accelerating wound healing.


Assuntos
Cálcio/metabolismo , Liberação de Histamina/efeitos da radiação , Mastócitos/efeitos da radiação , Animais , Linhagem Celular Tumoral , Mastócitos/metabolismo , Ratos , Espectrometria de Fluorescência , Canais de Cátion TRPV/metabolismo
10.
Photomed Laser Surg ; 22(6): 477-82, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15684746

RESUMO

OBJECTIVE: The purpose of this study was to investigate the in vitro effects of He-Ne laser irradiation on some rheological factors of human blood, such as blood viscosity, erythrocyte deformability, and sedimentation rate. BACKGROUND DATA: The intravascular irradiation of low power laser has been applied in pre-clinical and clinical to treat various pathological processes. However, the mechanism is not fully understood so far. Especially the interaction and related mechanism between the laser and blood are unclear. In this work, by measuring the change of the main rheological factors after laser irradiation, the interaction and mechanism were explored. METHODS: A30-mW He-Ne laser was used for irradiation with a 4-5-mm-diameter beam spot on blood samples, with a fluence rate of about 150 mW/cm.(2) The irradiation time was 60 min, so the total dose of irradiation was 540 J/cm.(2) The pathological samples of blood were obtained from patients (volunteers), and each sample was divided into two tubes for irradiation and control. The blood viscosity, erythrocyte deformability, and sedimentation rate were measured after laser irradiation and compared with un-irradiated control. The blood samples with poor erythrocyte deformability were prepared by adding Ca(2+) to the normal erythrocytes of a healthy person for investigating the laser effect on erythrocyte deformability further. RESULTS: Laser irradiation reduced the erythrocyte sedimentation rate of blood samples, which had a hyper-sedimentation rate originally. The blood viscosity of samples in hyper-values was lowered by laser irradiation in all shear rates measured (10-110 S(-1)), with a relative variation of approximately 10%. The deformability of erythrocytes from pathological samples and Ca(2+)-treated samples was improved after laser irradiation. CONCLUSIONS: The positive effects of laser irradiation on improving the rheological properties of blood were demonstrated in vitro.


Assuntos
Viscosidade Sanguínea/efeitos da radiação , Deformação Eritrocítica/efeitos da radiação , Hemorreologia/efeitos da radiação , Lasers , Sedimentação Sanguínea , Hélio , Hematócrito , Humanos , Neônio
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