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1.
Opt Lett ; 44(2): 391-394, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30644908

RESUMO

We demonstrate a volumetric two-photon microscopy (TPM) using the non-diffracting Airy beam as illumination. Direct mapping of the imaging trajectory shows that the Airy beam extends the axial imaging range around six times longer than a traditional Gaussian beam does along the propagation direction, while maintaining a comparable lateral width. Benefiting from its non-diffracting nature, the TPM with Airy beam illumination is able not only to capture a volumetric image within a single frame, but also to acquire image structures behind a strongly scattered medium. The volumetric specimen is mapped layer by layer under Gaussian mode, while the three-dimensional structure is projected to a single two-dimensional image under Airy mode, leading to a significantly increased acquisition speed. The performance of the TPM is evaluated employing a phantom of agarose gel imbedding fluorescent beads as well as a mouse brain slice. Finally, we showcase the penetration ability of the developed Airy TPM by imaging through a scattering environment.


Assuntos
Microscopia/métodos , Fenômenos Ópticos , Fótons , Animais , Encéfalo/diagnóstico por imagem , Camundongos , Distribuição Normal , Imagens de Fantasmas
2.
Opt Lett ; 44(21): 5238-5241, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674977

RESUMO

We demonstrate dual-Airy-beam-scanning-based volumetric two-photon microscopy (TPM) with depth-resolving capability. A pair of Airy beams with opposite acceleration is used as the excitation lights to sequentially illuminate the sample, and depth information can be resolved based on the deflection of the Airy beam. The depth-resolving range of the volumetric TPM is up to 32 µm. The advantages of the depth-resolved volumetric TPM are the depth-resolving capability over Bessel-beam-based TPM and less scanning times over traditional Gaussian-beam-based TPM. The depth-resolved volumetric TPM provides a promising fast imaging tool to study the dynamics in neural biology.

3.
Opt Express ; 25(15): 16996-17003, 2017 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-28789198

RESUMO

A new hollow fiber sensor based on metal-cladding waveguide configuration for the detection of the refractive index of liquid is proposed and demonstrated. Due to the existence of both surface and guided modes in the metal-insulator-metal waveguide, the proposed sensor can detect liquid with refractive index either higher or lower than the insulator layer, which significantly extends the detection range. The characteristics of metal-cladding waveguide is analyzed and presented, while the performance of the sensor is numerically calculated and evaluated. The results evince that, the designed fiber sensor can effectively detect both high and low refractive index liquid by respectively exciting surface mode and guided mode.

4.
Opt Express ; 24(14): 16016-26, 2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27410871

RESUMO

A new optical fiber sensor based on Bloch surface wave was theoretically proposed. An omnidirectional one-dimensional photonic crystal was designed as the multilayer coated on the outer surface of the optical fiber. Taking advantages of the omnidirectional reflection band, there is only surface mode resonance in the transmission spectrum, while guided mode resonance is avoided. The performance of the designed fiber sensor was analyzed theoretically with a ray transmission model. The presented sensor has comparable sensitivity but much higher figure of merit than other fiber sensors. The resolution can reach about 10-6 RIU or even higher.

5.
Opt Lett ; 41(11): 2478-81, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27244393

RESUMO

We presented the significant enhancement of the photonic spin Hall effect by taking advantage of long-range surface plasmon resonance (LRSPR). The influence of the thicknesses of metal and dielectric layers in the insulator-metal-insulator structure which supports LRSPR was investigated. Under the optimal parameter setup, the largest transverse separation with a 632.8 nm incident Gaussian beam reaches 7.85 µm, which is much larger than previous reported values.

6.
J Proteome Res ; 12(2): 692-703, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23227912

RESUMO

Chronic kidney disease (CKD) is becoming a worldwide public health problem. In this study, a kidney metabonomics method based on the ultra performance liquid chromatography/high-sensitivity mass spectrometry with MS(E) data collection technique was undertaken to explore the excretion pattern of low molecular mass metabolites in rat model of adenine-induced chronic renal failure (CRF). Coupled with blood biochemistry and kidney histopathology results, the significant difference in metabolic profiling between the adenine-induced CRF group and the control group by using pattern recognition analysis indicated that changes in global tissue metabolites were occurred. Some significantly changed metabolites like fatty acids, p-cresol sulfate, and indoxyl sulfate have been identified. The results showed that the most important CRF-related metabolites were polyunsaturated fatty acids, indoxyl sulfate, and p-cresyl sulfate. Indoxyl sulfate and p-cresyl sulfate (uremic toxins) were significantly increased in CRF rats. Indoxyl sulfate and p-cresyl sulfate stimulate progressive tubulointerstitial fibrosis by increasing the expression of transforming growth factor-ß1 (TGF-ß1). These biochemical changes in tissue metabolites are related to the perturbations of fatty acid metabolism and amino metabolism, which may be helpful to further understand the TGF-ß1 mechanisms of tubulointerstitial fibrosis. This work shows that the metabonomics method is a valuable tool for studying the essence of CKD.


Assuntos
Túbulos Renais/química , Metaboloma , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/urina , Fator de Crescimento Transformador beta1/metabolismo , Adenina , Animais , Cromatografia Líquida de Alta Pressão , Cresóis/urina , Ácidos Graxos Insaturados/urina , Fibrose , Expressão Gênica , Indicã/urina , Testes de Função Renal , Túbulos Renais/patologia , Masculino , Ratos , Insuficiência Renal Crônica/induzido quimicamente , Ésteres do Ácido Sulfúrico/urina , Espectrometria de Massas em Tandem , Fator de Crescimento Transformador beta1/genética
7.
Phytother Res ; 27(7): 1074-85, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22975930

RESUMO

A rapid, highly sensitive, and selective method was applied in a non-invasive way to investigate the antidepressant action of Xiaoyaosan (XYS) using ultra performance liquid chromatography-mass spectrometry (UPLC-MS) and chemometrics. Many significantly altered metabolites were used to explain the mechanism. Venlafaxine HCl and fluoxetine HCl were used as chemical positive control drugs with a relatively clear mechanism of action to evaluate the efficiency and to predict the mechanism of action of XYS. Urine obtained from rats subjected to chronic unpredictable mild stress (CUMS) was analyzed by UPLC-MS. Distinct changes in the pattern of metabolites in the rat urine after CUMS production and drug intervention were observed using partial least squares-discriminant analysis. The results of behavioral tests and multivariate analysis showed that CUMS was successfully reproduced, and a moderate-dose XYS produced significant therapeutic effects in the rodent model, equivalent to those of the positive control drugs, venlafaxine HCl and fluoxetine HCl. Metabolites with significant changes induced by CUMS were identified, and 17 biomarker candidates for stress and drug intervention were identified. The therapeutic effect of XYS on depression may involve regulation of the dysfunctions of energy metabolism, amino acid metabolism, and gut microflora changes. Metabonomic methods are valuable tools for measuring efficacy and mechanisms of action in the study of traditional Chinese medicines.


Assuntos
Antidepressivos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Trato Gastrointestinal/microbiologia , Redes e Vias Metabólicas/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Fitoterapia , Animais , Antidepressivos/urina , Benzoatos/urina , Biomarcadores/urina , Hidrocarbonetos Aromáticos com Pontes/urina , Catequina/urina , Chalcona/análogos & derivados , Chalcona/urina , Cromatografia Líquida , Ácido Cítrico/urina , Ciclo do Ácido Cítrico/efeitos dos fármacos , Ácidos Cumáricos/urina , Creatina Quinase/efeitos dos fármacos , Creatina Quinase/urina , Creatinina/urina , Cicloexanóis/uso terapêutico , Medicamentos de Ervas Chinesas/análise , Flavanonas/urina , Fluoxetina/uso terapêutico , Ácido Gálico/urina , Glucosídeos/urina , Glicina/análogos & derivados , Glicina/efeitos dos fármacos , Glicina/urina , Hipuratos/urina , Ácidos Cetoglutáricos/urina , Ácido Cinurênico/urina , Masculino , Espectrometria de Massas , Metabolômica , Monoterpenos , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/tratamento farmacológico , Triptofano/efeitos dos fármacos , Triptofano/urina , Tirosina/efeitos dos fármacos , Tirosina/urina , Cloridrato de Venlafaxina
8.
Cancer Manag Res ; 13: 1449-1458, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603487

RESUMO

PURPOSE: Transcutaneous electrical acupoint stimulation (TEAS) is an innovative choice for postoperative pain management. However, the safety and effectiveness of this traditional Chinese medicine (TCM) therapy for patients who underwent gastrectomy is largely unknown. So, the purpose of this study is to evaluate the safety and effectiveness of TEAS for patients who underwent gastrectomy. PATIENTS AND METHODS: We recruited 96 patients with gastric cancer from May 2019 to November 2019; 82 patients were enrolled, and 81 patients completed. Patients were randomly assigned to TEAS group (TG) received TEAS on postoperative day (POD) 1-3 or control group (CG) at a 1:1 ratio. The primary outcomes were pain score and consumption of analgesics. The secondary were the time of first postoperative flatus and defecation, frequency of postoperative nausea, vomiting, distention, diarrhea, comfort of semi-fluid diet, Clavien-Dindo grade (C-D grade) and length of postoperative day. We performed hematological analysis to explore the possible mechanisms. RESULTS: Overall, 81 patients were enrolled included in the analysis. Compared with CG, pain scores in TG were lower on POD 1-5 (average: 2.55±0.21 vs 3.10±0.42, P<0.001), and the use rate of opioids was lower (43.9 vs 75.0, P=0.004); time of first postoperative flatus (55.63±16.74 vs 72.60±20.92, P<0.001) and defecation (72.20±16.24 vs 95.78±17.75, P<0.001) were shorter; the frequency of nausea were fewer (1.88±1.09 vs 2.58±0.77, P=0.029) and patients were more comfortable with semi-fluid diet (7.63±0.63 vs 6.93±0.69, P<0.001); among the hematologic results, ß-endorphin (ß-End), interleukin-2 (IL-2), motilin (MTL) on POD 3, POD 5 were lower, 5-hydroxytryptamine (5-HT), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) were higher. And no adverse event was reported. CONCLUSION: TEAS can relieve postoperative pain and promote the recovery of gastrointestinal function. Consequently, it can be an adjunctive therapy to enhance postoperative recovery for patients after gastrectomy.

9.
J Pharm Biomed Anal ; 47(4-5): 847-53, 2008 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-18502075

RESUMO

Herba Artemisiae Scopariae is a Chinese herbal medicine widely used for the remedy of liver diseases. A high performance liquid chromatography method coupled with diode array detection was developed to simultaneously determine 13 different bioactive compounds in Herba Artemisiae Scopariae (Yin Chen) including chlorogenic acid (1), 6,7-dihydroxycoumarin (2), caffeic acid (3), 4-hydroxyacetophenone (4), scopoletin (5), rutin (6), hyperoside (7), isoquercitrin (8), scoparone (11), 7-methoxycoumarine (12) and quercetin (13). By using four different wavelengths in the HPLC analysis, the developed method was able to determine the bioactive compounds with excellent resolution, precision and recovery. The method was applied to determine the amounts of the bioactive compounds in nine samples from different cultivated regions and harvest seasons in China, and significant variations were revealed. Chlorogenic acid was the most abundant among the analyzed compounds. The samples harvested in the spring contained higher contents of chlorogenic acid than those collected in other seasons. Other phenolic acids as caffeic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid and 4-hydroxyacetophenone accumulated at much higher amounts in about May to July. The samples analyzed contained a much lower level of the amount of other flavonoids and coumarins as rutin, hyperoside, isoquercitrin and scoparone.


Assuntos
Artemisia/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicina Tradicional Chinesa , Estações do Ano , Acetofenonas/análise , Acetofenonas/química , Ácidos Cafeicos/análise , Ácidos Cafeicos/química , Calibragem , China , Ácido Clorogênico/análogos & derivados , Ácido Clorogênico/análise , Ácido Clorogênico/química , Estabilidade de Medicamentos , Metanol/química , Estrutura Molecular , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Padrões de Referência , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Temperatura , Fatores de Tempo , Água/química
10.
PLoS One ; 8(3): e59617, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23555727

RESUMO

The surface layer of Poria cocos (Fu-Ling-Pi, FLP) is commonly used in traditional Chinese medicine and its diuretic effect was confirmed in rat. Ultra performance liquid chromatography/quadrupole time-of-flight high-sensitivity mass spectrometry and a novel mass spectrometry(Elevated Energy) data collection technique was employed to investigate metabonomic characteristics of chronic kidney disease (CKD) induced from adenine excess and the protective effects of FLP. Multiple metabolites are detected in the CKD and are correlated with progressive renal injury. Among these biomarkers, lysoPC(18∶0), tetracosahexaenoic acid, lysoPC(18∶2), creatinine, lysoPC (16∶0) and lysoPE(22∶0/0∶0) in the FLP-treated group were completely reversed to levels in the control group which lacked CKD. Combined with biochemistry and histopathology results, the changes in serum metabolites indicate that the perturbations of phospholipids metabolism, energy metabolism and amino acid metabolism are related to adenine-induced CKD and to the interventions of FLP on all the three metabolic pathways. FLP may regulate the metabolism of these biomarkers, especially their efficient utilization within the context of CKD. Furthermore, these biomarkers might serve as characteristics to explain the mechanisms of FLP.


Assuntos
Adenina/efeitos adversos , Espectrometria de Massas/métodos , Medicina Tradicional Chinesa , Metabolômica/métodos , Poria/química , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/patologia , Animais , Biomarcadores/metabolismo , Cromatografia Líquida de Alta Pressão , Fibrose , Masculino , Ratos , Ratos Sprague-Dawley , Insuficiência Renal Crônica/induzido quimicamente , Insuficiência Renal Crônica/metabolismo , Reprodutibilidade dos Testes
11.
Bioanalysis ; 4(6): 713-23, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22452262

RESUMO

BACKGROUND: Rhaponticin (Rheum L.) demonstrates a variety of pharmacological activities, including antitumor, antithrombotic and antioxidant effect. However, there is no information describing the pharmacokinetics, bioavailability and metabolism of rhaponticin after intravenous administration. RESULTS: UHPLC-Q-TOF/MS and UHPLC-multistage tandem MS methods were developed for the pharmacokinetics, bioavailability and metabolism of rhaponticin in rats. The metabolite of rhaponticin, rhapontigenin, a potent inhibitor of cytochrome P450, was confirmed by UHPLC-multistage tandem MS. The plasma profile of rhaponticin and rhapontigenin was determined by UHPLC-Q-TOF/MS. The results showed that rhaponticin was rapidly distributed and eliminated from rat plasma. The absolute oral bioavailability of rhaponticin was calculated to be 0.03%. The plasma concentrations of rhapontigenin rapidly increased and gradually eliminated after intravenous administration. CONCLUSION: The present pharmacokinetics, bioavailability and metabolism studies of rhaponticin will provide helpful information for development of suitable dosage forms and clinical references on rational administration.


Assuntos
Cromatografia Líquida de Alta Pressão , Espectrometria de Massas/métodos , Estilbenos/metabolismo , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Estabilidade de Medicamentos , Espectrometria de Massas/instrumentação , Ratos , Estilbenos/sangue , Estilbenos/química , Estilbenos/farmacocinética
12.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 22(5): 368-70, 2006 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17144456

RESUMO

OBJECTIVE: To investigate the expression of TGF-betaR I, Smad2, Smad3 and Smad7 in keloids, normal scars and normal skins. Discuss the significance of these proteins in the course of keloid. METHODS: Immunohistochemistry method was used to detect the expression intensity and distribution of these proteins in above 3 kinds of different tissues in 44 cases. Statistics was used to analyze the data. RESULTS: The expression of TGF-betaR I were much stronger in keloid than in the other two tissues. The expression of Smad7 were lower in keloids. The increase expression of Smad2,3 were not obvious, but they were found to accumulate in the nucleus. CONCLUSIONS: The results indicate that over-expression of TGF-betaR I, low-expression of Smad7 and accumulation of Smad2,3 may be one of the etiological factors of keloids. This research may provide a new idea to prevent and treat keloids or other fibrosis diseases in the future.


Assuntos
Queloide/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Proteína Smad7/metabolismo , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptor do Fator de Crescimento Transformador beta Tipo I , Adulto Jovem
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