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1.
Bioengineering (Basel) ; 11(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38391636

RESUMO

Human walking parameters exhibit significant variability depending on the terrain, speed, and load. Assistive exoskeletons currently focus on the recognition of locomotion terrain, ignoring the identification of locomotion tasks, which are also essential for control strategies. The aim of this study was to develop an interface for locomotion mode and task identification based on a neuromuscular-mechanical fusion algorithm. The modes of level and incline and tasks of speed and load were explored, and seven able-bodied participants were recruited. A continuous stream of assistive decisions supporting timely exoskeleton control was achieved according to the classification of locomotion. We investigated the optimal algorithm, feature set, window increment, window length, and robustness for precise identification and synchronization between exoskeleton assistive force and human limb movements (human-machine collaboration). The best recognition results were obtained when using a support vector machine, a root mean square/waveform length/acceleration feature set, a window length of 170, and a window increment of 20. The average identification accuracy reached 98.7% ± 1.3%. These results suggest that the surface electromyography-acceleration can be effectively used for locomotion mode and task identification. This study contributes to the development of locomotion mode and task recognition as well as exoskeleton control for seamless transitions.

2.
Food Chem ; 324: 126854, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353655

RESUMO

Licorice, as a nutritional plant extensively used in food fields, grows in various origins of the world as wild and cultivated types. But existing methods were not adequate for quality estimation of licorice samples from multiple sources till date. In the present research, HPLC, UV and FT-IR were applied together to establish fingerprint profiles of licorice (Glycyrrhiza glabra L.) samples. Then, an appropriate quantitative method was adopted to evaluate their qualities. Furthermore, eight active chemical compositions and the potential antioxidant capacities of licorice samples were determined, and their intrinsic characteristics were excavated by chemometric methods. The results showed that the ingredient content and antioxidant capacity of licorice were closely related to the origin and growth type, and the established method was capable of accurately classifying wild and cultivated licorice samples from nine habitats into five quality grades. This study provides a novel and comprehensive strategy for food quality assessment.


Assuntos
Antioxidantes/química , Glycyrrhiza/química , Extratos Vegetais/química , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Ecossistema , Glycyrrhiza/crescimento & desenvolvimento , Glycyrrhiza/metabolismo , Análise de Componente Principal , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Artigo em Inglês | MEDLINE | ID: mdl-31756622

RESUMO

Alkaloids of Sophora flavescens (ASF) has various pharmacological effects, and it is widely used in clinical practice. The aim of this research was to develop an environmentally friendly methodology that enables not only identification but also the quality consistency assessment of Alkaloids of Sophora flavescens. A background electrolyte composed of 50 mmol/L sodium tetraborate solution, 500 mmol/L boric acid and 1.2 mmol/L citric acid was used to conduct the fingerprint analysis coupled with quantitative determination of three components. Linear quantitative profiling method was used for comprehensive quality discrimination of the test samples from both qualitative and quantitative perspectives, and the 27 batches of samples were well differentiated. In addition, the fingerprint-efficacy relationship between chemical components and antioxidant activity in vitro was established using partial least squares regression model, which provided important medicinal efficacy information for quality control.


Assuntos
Alcaloides/análise , Antioxidantes/análise , Eletroforese Capilar/métodos , Sophora/química , Alcaloides/química , Antioxidantes/química , Análise dos Mínimos Quadrados , Limite de Detecção , Extratos Vegetais/química , Análise de Componente Principal , Reprodutibilidade dos Testes
4.
Phytomedicine ; 59: 152790, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31005815

RESUMO

BACKGROUND: Herbal medicine (HM), as a complex system, is difficult to investigate their quality consistency effectively by chromatographic fingerprinting obtained in a single detection method. Moreover, active compound discovery affords no information about pharmacological activity until late in the discovery process, and the interaction between HMs in vitro is not yet clear, which requires sufficient practice to prove their effectiveness. PURPOSE: Therefore, the purpose of this study was to improve the quality control methods of Compound Liquorice Tablet (CLT) using multi-wavelength fusion fingerprinting, explore the possible antioxidant components and assess the interaction between herbs combined with bioactivity evaluation. METHODS AND DESIGN: Once the theoretical standard preparation obtained in combination of multi-wavelength fusion fingerprinting and hierarchical clustering analysis, averagely linear quantified fingerprint method could rapidly calculate the composition similarities and efficiently quantify the multiple components of CLTs without any chemical standard. Furthermore, the fingerprint-efficacy relationship was investigated by integrating high performance liquid chromatography fingerprints with antioxidant activity assessment using the partial least squares model, which was capable of directly discovering the bioactive ingredients. Hereafter, combination index value was introduced to evaluate the correlation between the two antioxidant herbs in CLT formula. RESULTS: The results showed that CLT samples were effectively identified and quantified, and their quality was accurately distinguished. By analyzing the antioxidant evaluation results, it was found that CLT had strong antioxidant activity, and through the study on PLS model and antioxidant activity assay of individual compounds, it was found that the order of chemical constituents responsible for antioxidant activity in CLT was as follows: flavonoids > saponins > alkaloids. Finally, it was determined that the CI value of GE-PPCE was in the range of 1.20-1.61, indicating that the interaction of the GE-PPCE pair was a slight antagonism. CONCLUSION: Thus, this study provided a preferred way for monitoring the quality consistency of HM, exploring possible bioactive components of HMs and assessing the interaction between herbs.


Assuntos
Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/normas , Glycyrrhiza/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/estatística & dados numéricos , Análise dos Mínimos Quadrados , Análise de Componente Principal , Controle de Qualidade , Padrões de Referência , Comprimidos/química , Comprimidos/normas , Terpenos/análise
5.
Sci Rep ; 9(1): 1309, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718789

RESUMO

This study was to evaluate the quality consistency of glycyrrhiza extract and to explore the possible anti-oxidant components in combination with chromatographic fingerprint and bioactivity evaluation. Characteristic fingerprints of glycyrrhiza extract samples from different sources were generated by high performance liquid chromatography with diode array detector (HPLC-DAD) and evaluated using hierarchical clustering and similarity analysis. Compared with the conventional qualitative similarity evaluation method, the averagely linear quantified fingerprint method had an important quantitative similarity parameter supported by quantitative analysis, which was recommended in the fingerprint evaluation. Antioxidant activities of the glycyrrhiza extract samples were determined by DPPH (2, 2-diphenyl-1-picryldrazyl) radical scavenging assays. In addition, the fingerprint-efficacy relationship was investigated by the chemical fingerprints and the anti-oxidant activities utilizing partial least squares model, which was capable of exploring and discovering the bioactive components of glycyrrhiza extracts. Therefore, the present study provided a powerful strategy to evaluate the holistic quality consistency of medicinal plant.


Assuntos
Glycyrrhiza/química , Modelos Teóricos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Algoritmos , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Estrutura Molecular , Relação Estrutura-Atividade
6.
Mol Med Rep ; 17(6): 8137-8144, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29658570

RESUMO

Breast cancer is the second leading cause of cancer­associated mortality, and metastatic breast cancer is responsible for 90% of patient mortalities. Given that JWA represses the proliferation, invasion and metastasis of a number of other human tumor cells, including melanoma, esophageal, hepatocellular and gastric carcinomas, via mitogen­activated protein kinase or integrin signaling, the present study investigated the expression and function of JWA in human breast cancers. The results showed that the expression level of JWA was significantly reduced in human primary breast cancers when compared with the paired adjacent tissues. Downregulating JWA enhanced, while overexpressing JWA suppressed, the migration and invasion abilities of the two breast cancer cell lines, MDA­MB­468 and MDA­MB­231, without affecting their proliferations in vitro. In addition, JWA negatively regulated the surface expression of CXCR4 in the two cell lines via proteasome degradation, though not via transcriptional inhibition. Functionally, normalizing the disturbed expressions of CXCR4 largely reversed the inhibitory effect of JWA on cell invasion. These data demonstrated that JWA suppressed the migration/invasion of breast carcinoma cells by downregulating the expression of CXCR4, and suggested that JWA may harbor prognostic and therapeutic potential in patients with breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Receptores CXCR4/genética , Biomarcadores , Biomarcadores Tumorais , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , Proteínas de Membrana Transportadoras , Proteólise
7.
Mol Med Rep ; 17(2): 2853-2860, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29207147

RESUMO

Gastric cancer (GC) is one of the most common malignancies in the world. It is essential to develop novel targets and therapeutic approaches for GC, which requires identification of novel functional molecules. WW­domain containing transcription regulator 1 (WWTR1) may activate many transcriptional factors and exhibit an important role in the development of various tissues in mammals. The results of the present study demonstrated that mRNA and protein levels of WWTR1 are increased in GC tissues and cell lines. The SGC7901 cell line was selected to perform RNA interference (RNAi) targeting WWTR1, and for subsequent study. Compared with control groups (cells without any treatment) and mock groups (cells treated with nonspecific siRNA), cell proliferation of siWWTR1 cells (cells treated with WWTR1 siRNA) was detected using a Cell Counting Kit­8 assay at 12, 24 and 48 h, and decreased in a time­dependent manner. Cell cycle and apoptosis status were determined by flow cytometry, and it was demonstrated that G1/S transition was blocked in the cell cycle and apoptosis promoted in siWWTR1 cells, compared with control and mock cells. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to detect the mRNA and protein levels of cell cycle and apoptosis­associated factors. The expression of Cyclin D1, cancer Myc and B cell lymphoma/leukemia­2 (Bcl­2) decreased and Bcl­2 associated X protein increased significantly in siWWRT1 cells, at the mRNA and protein level, compared with control and mock cells. With the exception of the Hippo pathway, siWWTR1 regulated downstream factors, including mothers against decapentaplegic homolog family member 3 (SMAD3) and inhibitor of DNA binding 1, HLH protein (ID1), HLH protein in the transforming growth factor (TGF)­ß pathway. The expression of asparagine synthetase was decreased whereas ID1, SMAD3 (proteins that participate in intracellular TGF­ß transduction) and betacellulin increased notably in siWWRT1 cells. In conclusion, WWTR1 promotes cell proliferation and inhibits apoptosis of GC cells by regulating cell cycle/apoptosis­associated factors, and effectors in the TGF­ß pathway.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Interferência de RNA , Neoplasias Gástricas/genética , Adulto , Idoso , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Transdução de Sinais , Neoplasias Gástricas/metabolismo , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional
8.
RSC Adv ; 8(49): 27661-27673, 2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35542699

RESUMO

Traditional Chinese medicines (TCM)/herbal medicines (HM) are too complicated to comprehensively investigate their quality consistency effectively with a single detection technique. Hence, finding an effective, rapid, and comprehensive quality control (QC) method is of great importance for guaranteeing the safety and efficacy of TCM/HM in clinical applications. In our current research, a novel strategy of multi-wavelength fusion HPLC fingerprints and ultraviolet (UV) spectroscopic fingerprinting was proposed and successfully applied to monitor the quality consistency of compound liquorice tablets (CLT). The quality grades of 35 CLT samples from two manufacturers were successfully discriminated and evaluated by the averaged linear quantified fingerprint method (ALQFM) from a qualitative and quantitative perspective. The results showed that the UV spectroscopic fingerprints agreed well with the multi-wavelength fusion HPLC fingerprints. In addition, ultra-high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UHPLC-ESI-Q-TOF-MS) was applied to investigate the chemical constituents in CLT samples, providing an important chemical structural foundation for further QC and bioactivity studies. Additionally, a simple flow injection analysis (FIA) was developed to investigate the antioxidant capacity in CLT, which was based on the scavenging of 2,2-diphenyl-1-picrylhydrazyl radicals by antioxidants. Furthermore, the fingerprint-efficacy relationship between high-performance liquid chromatography (HPLC) fingerprints and the antioxidant activities of CLT samples was established utilizing orthogonal projection to latent structures (OPLS). In conclusion, this study indicated that integrating UHPLC-ESI-Q-TOF-MS/MS, UV spectroscopic fingerprints, and multi-wavelength fusion HPLC fingerprints coupled with the antioxidant activities reported could give important clues for further pharmacological and clinical studies of CLT. Meanwhile, it provides a practical strategy for the rapid screening and identifying of TCM/HM quality consistency.

9.
Se Pu ; 35(7): 741-747, 2017 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-29048839

RESUMO

The fusion high performance liquid chromatographic fingerprint combined with quantification and principal component analysis (PCA) was successfully developed, which was applied to assess the quality consistency of 25 Yinqiaojiedu tablets (YQJDTs). The resolution index I was employed as an objective function to evaluate chromatographic conditions. The chromatographic fingerprints were established by reversed-phase high performance liquid chromatography. The wavelengths were set at 230, 279 and 327 nm, separately. Then, the three wavelength fusion fingerprint was developed by the technique of multi-wavelength fusion fingerprint. The linearity, precision, repeatability, stability and accuracy of the method were proved to meet the fingerprint analysis criteria. Subsequently, the systematic quantified fingerprint method was applied for integrative quality discrimination of YQJDTs from both qualitative and quantitative perspectives. The results showed that the quality of 25 YQJDTs from the two manufacturers were completely qualified and well differentiated. The contents of six components were determined simultaneously and combined with fingerprint analysis. It was used to evaluate the quality of YQJDT from the overall and partial points of view. In addition, the PCA of the fusion fingerprint data was applied to get the score plot. It can be clearly distinguished the 25 YQJDT samples from the two manufacturers. The method proposed in this study was comprehensive and reliable, which could be used for a valuable reference to scientifically evaluate and effectively control the quality of YQJDT.


Assuntos
Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Análise de Componente Principal , Cromatografia de Fase Reversa , Controle de Qualidade , Comprimidos
10.
Onco Targets Ther ; 10: 543-550, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28203087

RESUMO

BACKGROUND: MicroRNAs (miRNAs) have been shown to be involved in the initiation and progression of cancers in the literature. In this study, we aimed to evaluate the clinicopathological role of miR-17 in breast cancer. MATERIALS AND METHODS: The expression of miR-17 was measured in 132 breast cancer tissues and paired adjacent normal tissues by using real-time quantitative polymerase chain reaction. The association between miR-17 expression levels and clinicopathological parameters was also analyzed. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and flow cytometry assays were used to investigate the role of miR-17 in the regulation of breast cancer cells. RESULTS: The expression of miR-17 was remarkably increased in breast cancer tissues and cell lines. Clinical association analysis revealed that a high expression of miR-17 was prominently associated with poor survival time in breast cancer. Overexpression of miR-17 promoted cell proliferation and induced tumor growth. CONCLUSION: Our findings clarified that the upregulation of miR-17 played a vital role in breast cancer progression and suggested that miR-17 could be used as a prognostic biomarker for breast cancer.

11.
J Sep Sci ; 38(12): 2174-81, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25867134

RESUMO

Micellar electrokinetic chromatography fingerprinting combined with quantification was successfully developed and applied to monitor the quality consistency of Weibizhi tablets, which is a classical compound preparation used to treat gastric ulcers. A background electrolyte composed of 57 mmol/L sodium borate, 21 mmol/L sodium dodecylsulfate and 100 mmol/L sodium hydroxide was used to separate compounds. To optimize capillary electrophoresis conditions, multivariate statistical analyses were applied. First, the most important factors influencing sample electrophoretic behavior were identified as background electrolyte concentrations. Then, a Box-Benhnken design response surface strategy using resolution index RF as an integrated response was set up to correlate factors with response. RF reflects the effective signal amount, resolution, and signal homogenization in an electropherogram, thus, it was regarded as an excellent indicator. In fingerprint assessments, simple quantified ratio fingerprint method was established for comprehensive quality discrimination of traditional Chinese medicines/herbal medicines from qualitative and quantitative perspectives, by which the quality of 27 samples from the same manufacturer were well differentiated. In addition, the fingerprint-efficacy relationship between fingerprints and antioxidant activities was established using partial least squares regression, which provided important medicinal efficacy information for quality control. The present study offered an efficient means for monitoring Weibizhi tablet quality consistency.


Assuntos
Antioxidantes/química , Cromatografia Capilar Eletrocinética Micelar , Medicamentos de Ervas Chinesas/química , Boratos/química , Eletrólitos , Análise dos Mínimos Quadrados , Análise Multivariada , Extratos Vegetais/química , Controle de Qualidade , Reprodutibilidade dos Testes , Dodecilsulfato de Sódio/química , Hidróxido de Sódio/química , Comprimidos/química
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