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1.
Angew Chem Int Ed Engl ; 61(11): e202115561, 2022 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-34989066

RESUMEN

Sensitive sensing is critical when developing new calculation systems with weak input signals (ISs). In this work, a "weak-inputs-strong-outputs" strategy was proposed to guide the construction of sensitive logic nanodevices by coupling an input-induced reversible DNA computing platform with a hybridization chain reaction-based signal amplifier. By rational design of the sequence of computing elements (CEs) so as to avoid cross-talking between ISs and signal amplifier, the newly formed logic nanodevices have good sensitivity to the weak ISs even at low concentrations of CEs, and are able to perform YES, OR, NAND, NOR, INHIBIT, INHIBIT-OR and number classifier operation, showing that the DNA calculation proceeds in dilute solution medium that greatly improves the calculation proficiency of logic nanodevices without the confinement of the lithography process in nanotechnology.

2.
Anal Chem ; 93(7): 3411-3417, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33565859

RESUMEN

In this work, we propose a three-layer hierarchical hybridization chain reaction (3L hHCR) composed of 1stHCR, 2ndHCR, and 3rdHCR to achieve robust signal amplification efficiency and broaden the applied range of HCR-based systems. In principle, the execution of superior HCR generates the formation of the initiator (named as 2ndI or 3rdI) of the subordinate HCR that relies on the introduction of the target sequence (1stI). To avoid the high background signal of the 3L hHCR system, a strategy of "splitting reconstruction" was adopted. The initiator of the subordinate HCR was designed as two separate fragments (splitting) that are obtained together (reconstruction) for the motivation of the subordinate HCR after the completion of the superior HCR. The implementation of the entire 3L hHCR system generates significant fluorescence recovery that derives from the impediment of Förster resonance energy transfer between fluorophore and quencher; thus, ultrasensitive detection of 1stI in the range of 50 pM to 10 nM can be achieved. Surprisingly, when the concentration of 1stI is lower than 1 nM, the 3L hHCR shows excellent ability to discriminate against various concentrations of 1stI, which is better than that of the 2L hHCR I system. Due to the hierarchical self-assembly mechanism, the 3L hHCR can also be reliably operated as a cascade AND logic gate with a high specificity and molecular keypad lock with a prompt error-reporting function. Furthermore, the 3L hHCR-based molecular keypad lock also shows potential application in the accurate diagnosis of cancer. The 3 L hHCR shows visionary prospects in biosensing and the fabrication of advanced biocomputing networks.

3.
Anal Chem ; 93(7): 3526-3534, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33562958

RESUMEN

Precise drug delivery holds great promise in cancer treatment but still faces challenges in controllable drug release in tumor cells specifically. Herein, a nucleolin-targeted and telomerase-responsive DNA nanotube for drug release was developed. First, a DNA nanosheet with four capture strands on its surface was prepared, which could bind and load ricin A chain (RTA). The RTA-loaded nanosheet was further converted into a DNA nanotube with a high Förster resonance energy transfer (FRET) efficiency in the presence of a Cy3-modified DNA fastener by hybridizing with the Cy5-modified DNA and another DNA-containing telomerase primer sequence along the long sides. Moreover, the aptamer of nucleolin was assembled on the DNA nanotube by combining with the hybrid chain at the terminal. The aptamer-functionalized and RTA-loaded DNA nanotube displayed enhanced tumor permeability and precise drug release in response to the telomerase in tumor cells, following the change of the FRET signal and RTA-induced cell death. Moreover, the DNA nanotube was applied successfully in vivo, and there was an obvious inhibition of tumor growth on xenograft-bearing mice following systemic administration, indicating that the constructed DNA nanotube represents a promising platform for precise RTA delivery in target cancer therapy.


Asunto(s)
Nanotubos , Neoplasias , Telomerasa , Animales , ADN , Transferencia Resonante de Energía de Fluorescencia , Ratones , Neoplasias/tratamiento farmacológico , Fosfoproteínas , Proteínas de Unión al ARN , Telomerasa/genética , Telomerasa/metabolismo , Nucleolina
4.
Virol J ; 18(1): 22, 2021 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-33461581

RESUMEN

BACKGROUND: Oxidative stress is an important pathogenic factor in influenza A virus infection. It has been found that reactive oxygen species induced by the H9N2 influenza virus is associated with viral replication. However, the mechanisms involved remain to be elucidated. METHODS: In this study, the role of autophagy was investigated in H9N2 influenza virus-induced oxidative stress and viral replication in A549 cells. Autophagy induced by H9N2 was inhibited by an autophagy inhibitor or RNA interference, the autophagy level, viral replication and the presence of oxidative stress were detected by western blot, TCID50 assay, and Real-time PCR. Then autophagy and oxidative stress were regulated, and viral replication was determined. At last, the Akt/TSC2/mTOR signaling pathways was detected by western blot. RESULTS: Autophagy was induced by the H9N2 influenza virus and the inhibition of autophagy reduced the viral titer and the expression of nucleoprotein and matrix protein. The blockage of autophagy suppressed the H9N2 virus-induced increase in the presence of oxidative stress, as evidenced by decreased reactive oxygen species production and malonaldehyde generation, and increased superoxide dismutase 1 levels. The changes in the viral titer and NP mRNA level caused by the antioxidant, N-acetyl-cysteine (NAC), and the oxidizing agent, H2O2, confirmed the involvement of oxidative stress in the control of viral replication. NAC plus transfection with Atg5 siRNA significantly reduced the viral titer and oxidative stress compared with NAC treatment alone, which confirmed that autophagy was involved in the replication of H9N2 influenza virus by regulating oxidative stress. Our data also revealed that autophagy was induced by the H9N2 influenza virus through the Akt/TSC2/mTOR pathway. The activation of Akt or the inhibition of TSC2 suppressed the H9N2 virus-induced increase in the level of LC3-II, restored the decrease in the expression of phospho-pAkt, phospho-mTOR and phospho-pS6 caused by H9N2 infection, suppressed the H9N2-induced increase in the presence of oxidative stress, and resulted in a decrease in the viral titer. CONCLUSION: Autophagy is involved in H9N2 virus replication by regulating oxidative stress via the Akt/TSC2/mTOR signaling pathway. Thus, autophagy maybe a target which may be used to improve antiviral therapeutics.


Asunto(s)
Células Epiteliales Alveolares/virología , Autofagia/genética , Regulación de la Expresión Génica , Subtipo H9N2 del Virus de la Influenza A/fisiología , Infecciones por Orthomyxoviridae/veterinaria , Estrés Oxidativo/genética , Replicación Viral , Células A549 , Animales , Humanos , Subtipo H9N2 del Virus de la Influenza A/patogenicidad , Transducción de Señal , Porcinos
5.
Anal Bioanal Chem ; 413(9): 2457-2466, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33674935

RESUMEN

In this study, an effective and portable method for enzyme activity detection and inhibitory activity evaluation was developed based on the alkaline phosphatase (ALP)-mediated reaction in a personal glucose meter (PGM). In this method, ALP catalyzes the hydrolysis of substrate amifostine (WR-2721) to produce ethanethiol (WR-1065), which can trigger the reduction of ferricyanide (K3[Fe(CN)6]), an electron transfer mediator in glucose test strips, to ferrocyanide ([K4Fe(CN)6]) and generate a PGM-detectable signal. Thus, WR-1065 can be directly quantified by a PGM as simply as detecting glucose in blood. After being systematically optimized, the method was applied to evaluate the inhibitory activity of ten small-molecule compounds and six Cordyceps sinensis (CS) extracts on ALP. The results showed that adenosine-5-monophosphate and theophylline had high inhibitory activity, but two CS extracts have promotion potency on ALP with the values of -20.7 ± 1.3% and -46.6 ± 2.1%, respectively. Moreover, the binding sites and modes of small-molecule compounds to ALP were investigated by molecular docking, while a new substrate competitor with theoretically good inhibitory activity against ALP was designed by scaffold hopping. Finally, the accuracy of the PGM method for enzyme activity detection was assessed by detecting ALP from milk samples, and the recovery ranged from 87.7% to 116.9%. These results indicate that it is feasible to evaluate enzyme activity and the inhibitory activity of small-molecule compounds and CS extracts on ALP using a PGM based on ALP-mediated reaction. Graphical abstract.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Técnicas Biosensibles/métodos , Glucemia/análisis , Pruebas de Enzimas/métodos , Fosfatasa Alcalina/antagonistas & inhibidores , Técnicas Biosensibles/instrumentación , Pruebas de Enzimas/instrumentación , Inhibidores Enzimáticos/farmacología , Diseño de Equipo , Humanos , Modelos Moleculares
6.
Luminescence ; 35(2): 222-230, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31713314

RESUMEN

Energy transfer engineering based on fluorescent probes for directly sensing enzyme activities are in great demand as enzyme-mediated transformations, which are central to all biological processes. Here, a fluorescence carbon dot (CD)-based assay exhibiting selective responses to the quantitation of ß-glucosidase and the effect of its inhibitor was developed. The most common substrate, para-nitrophenyl-ß-d-glucopyranoside (pNPG) was hydrolyzed by ß-glucosidase to release p-nitrophenol (pNP), which can efficiently quench fluorescence of CDs via an inner filter effect and electron transfer. However, in the presence of inhibitors of ß-glucosidase, the fluorescence intensity gradually recovered as the concentration of inhibitors increased. Therefore, the enzyme-triggered fluorescence turn-off/turn-on of specific CDs successfully achieved sensitive detection of ß-glucosidase and monitored the effect of its inhibitors. This new strategy was applied to detect ß-glucosidase and monitor ß-glucosidase inhibitor in hepatoma cells using cell imaging. All results suggest that the new method is sensitive and promising for use in cancer diagnosis and treatment.


Asunto(s)
Carbono/metabolismo , Carcinoma Hepatocelular/diagnóstico por imagen , Inhibidores de Glicósido Hidrolasas/farmacología , Neoplasias Hepáticas/diagnóstico por imagen , Puntos Cuánticos/metabolismo , beta-Glucosidasa/antagonistas & inhibidores , beta-Glucosidasa/análisis , Carbono/química , Fluorescencia , Inhibidores de Glicósido Hidrolasas/química , Células Hep G2 , Humanos , Imagen Óptica , Puntos Cuánticos/química , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Células Tumorales Cultivadas , beta-Glucosidasa/metabolismo
7.
Acta Virol ; 64(4): 496-500, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32985209

RESUMEN

 The coronavirus disease 2019 (COVID-19) starting on 12 December 2019 in Wuhan, China, caused 7,885,123 cases including 431,835 deaths by 14 Jun 2020 all over the world. Here we report the genomic characterization and phylogenetic evolution of coronavirus SARS-CoV-2 causing COVID-19. The SARS-CoV-2 and other coronavirus genomes were obtained from GISAID and GenBank. The genomes were annotated and potential genetic recombination was investigated. Phylogenetic analysis was conducted and used to determine the evolutionary history of the virus and to elucidate the origin of the virus. The analysis had revealed that SARS-CoV-2 possessed a similar genomic organization to bat-SARS-like-CoV collected in China. The genome sequences of SARS-CoV-2 were very similar, showing 99.6-100% sequence identity. Notably, SARS-CoV-2 was closely related (with 88% identity) to bat-SARS-like coronavirus, but was more distant from SARS-CoV (about 79%) and MERS-CoV (about 50%). Phylogenetic tree of the complete viral genome showed that the virus clustered with bat SARS-like coronavirus. The results of the similarity between SARS-CoV-2 and related viruses did not identify any potential genomic recombination events. Therefore, it seems that the SARS-CoV-2 might be originally hosted by bats, and might have been transmitted to humans via intermediate hosts of currently unknown wild animal(s). Finally, based on the wide spread of SARS-CoV in their natural reservoirs, future studies should focus more on surveillance of coronaviruses, and measures against the domestication and consumption of wild animals should be implemented. Keywords: coronavirus; SARS coronavirus; SARS-CoV-2; genomic characterization; phylogenetic evolution.


Asunto(s)
Evolución Molecular , Genoma Viral , Filogenia , SARS-CoV-2/genética , Animales , COVID-19 , China , Humanos
8.
Anal Chem ; 91(10): 6761-6768, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31020834

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) can progress gradually to liver failure, early warning of which is critical for improving the cure rate of NAFLD. In situ imaging and monitoring of overexpressed miR-21 is an advanced strategy for NAFLD diagnosis. However, this strategy usually suffers from the high background imaging in living cells owing to the complexity of the biological system. To overcome this problem, herein, we have developed a one-donor-two-acceptor nanoprobe by assembling gold nanoparticles (AuNPs) coupled with BHQ2 (AuBHQ) and quantum dots (QDs) through DNA hybridization for imaging of miR-21 in living cells. The fluorescence of QDs was quenched up to 82.8% simultaneously by the AuNPs and the BHQ2 via nanometal surface energy transfer and fluorescence resonance energy transfer, reducing the background signals for target imaging. This low background fluorescent nanoprobe was successfully applied for imaging the target miR-21 in nonalcoholic fatty liver cells by catalyzing the disassembly of QDs with the AuBHQ and the fluorescence recovery of QDs. In addition, the sensitivity of this nanoprobe has also been enhanced toward detecting miR-21 in the range of 2.0-15.0 nM with the detection limit (LOD, 3σ) of 0.22 nM, which was 13.5 times lower than that without BHQ2. The proposed approach provides a new way for early warning, treatments, and prognosis of NAFLD.


Asunto(s)
Colorantes Fluorescentes/química , Nanopartículas del Metal/química , MicroARNs/análisis , Puntos Cuánticos/química , Línea Celular , ADN/química , ADN/genética , ADN/toxicidad , Colorantes Fluorescentes/toxicidad , Oro/química , Oro/toxicidad , Humanos , Límite de Detección , Nanopartículas del Metal/toxicidad , MicroARNs/genética , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Hibridación de Ácido Nucleico , Puntos Cuánticos/toxicidad
9.
Zhongguo Zhong Yao Za Zhi ; 44(10): 1978-1982, 2019 May.
Artículo en Zh | MEDLINE | ID: mdl-31355550

RESUMEN

Online gradient extraction-high performance liquid chromatography( HPLC) method was developed for simultaneous determination of high and low polar components in Cordyceps. The sample powder of Cordyceps was uniformly mixed with diatomaceous earth,packed into extraction tank,and installed into the HPLC system. Online gradient extraction was conducted with mobile phase at 70 ℃. The separation was performed on Zorbax SB-AQ( 4. 6 mm×150 mm,5 µm) column with 0. 1% formic acid solution-methanol as the mobile phase for gradient elution at 1. 0 mL·min~(-1). The column temperature was 30 ℃,and detection wavelength was set at 260 nm. The results showed that the high and low polar components in Cordyceps could be simultaneously extracted and separated by the developed method. Meanwhile,six high polar compounds( uracil,uridine,thymine,inosine,guanosine and adenosine) and one low polar compound( ergosterol) were identified by comparison with the reference peaks. The established method is rapid,stable and environment friendly,which is helpful to improve the quality evaluation level for Cordyceps.


Asunto(s)
Cromatografía Líquida de Alta Presión , Cordyceps/química , Ergosterol/análisis , Nucleósidos/análisis
10.
Zhongguo Zhong Yao Za Zhi ; 44(10): 1983-1988, 2019 May.
Artículo en Zh | MEDLINE | ID: mdl-31355551

RESUMEN

In this study,the protein in different Cordyceps samples,which include fresh sample( S1),22 ℃ drying sample( S2),37 ℃ drying sample( S3) and 60 ℃ drying sample( S4),were analyzed by sodium dodecylsupinate-polyacrylamide gel electrophoresis( SDS-PAGE) and two-dimensional electrophoresis( 2-DE). The total protein contents in Cordyceps samples were from 1. 655-4. 493 mg·g~(-1) and the protein contents in fresh sample was the highest. The results of SDS-PAGE showed that the mainly ranges of protein molecular weight of Cordyces samples were 10-100 kDa and the numbers of protein bands were 28 to 41,the fresh sample had the maximum number of protein bands. The 2-DE profiles were analyzed by PDQuest software. The resulted indicated that 488-876 protein spots were detected in different Cordyceps samples and the isoelectric point( pI) was distributed between 4. 5 and 6. 5,the protein molecular weight was distributed in 10-20 kDa and 25-100 kDa,the fresh sample had the maximum number of protein spots. Therefore,the drying process could decrease contents and species of protein in Cordyceps,and the different drying conditions had different effects on protein. These results provide a reference for improving the drying process of Cordyceps.


Asunto(s)
Cordyceps/química , Desecación/métodos , Proteínas Fúngicas/análisis , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Peso Molecular
11.
Pak J Pharm Sci ; 32(1): 185-195, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30772808

RESUMEN

In the present study, the anti-platelet aggregation activity of 14 vegetables and fruits was tested in vitro. The aqueous, 90% ethanol and ethyl acetate extracts, as well as concentrated juices of 14 foods (fruits and vegetables) were prepared, and the anti-platelet aggregation activity of those extracts was analyzed on a platelet aggregation analyzer in vitro with adenosine 5'-diphosphate (ADP), bovine thrombin (THR) and arachidonic acid (AA) as aggregation inducers, respectively. Aspirin (ASP) was used as the positive control. A number of the tested foods had inhibitory effects in concentration-dependent manner on platelet aggregations induced by various agonists. Especially, some foods such as lemon, leek, garlic, scallion, ginger, tomato and grapefruit showed good anti-platelet aggregation effect similar or higher than that of positive control group i.e. aspirin (ASP). The results of present study provide scientific reference for reasonable selection of daily dietary with supplementary curative effects or prevention of cardiovascular diseases (CVD).


Asunto(s)
Jugos de Frutas y Vegetales , Frutas , Extractos Vegetales/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Verduras , Animales , Relación Dosis-Respuesta a Droga , Frutas/química , Masculino , Extractos Vegetales/aislamiento & purificación , Inhibidores de Agregación Plaquetaria/aislamiento & purificación , Pruebas de Función Plaquetaria , Conejos , Verduras/química
12.
Analyst ; 143(23): 5764-5770, 2018 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-30334036

RESUMEN

Ricin is an extremely potent ribosome-inactivating protein and serves as a likely food biocontaminant or biological weapon. Thus, simple, sensitive and accurate analytical assays capable of detecting ricin are urgently needed to be established. Herein, we present a novel method for ricin B-chain (RTB) detection by using two materials: (a) a highly efficient hybrid probe that was formed by linking a glucose oxidase (GOD)-encapsulated liposome (GOD-L) to magnetic beads (MBs) through hybridization between an aptamer and a blocker and (b) a new low-background g-C3N4-MnO2 sandwich nanocomposite that exhibits fluorescence resonance energy transfer (FRET) between the g-C3N4 nanosheet and MnO2. In the presence of RTB, the strong binding between RTB and the aptamer can release the blocker-linked liposome from the surface of the MBs. After magnetic separation, the decomposed liposome can release GOD to catalyze the oxidation of glucose, generating a certain amount of H2O2. Then, H2O2 can reduce MnO2 of the g-C3N4-MnO2 nanocomposite to Mn2+, which leads to the elimination of FRET. Thus, the fluorescence of the g-C3N4 nanosheet will be turned on. Because of the excellent signal amplification ability of liposome and the characteristic highly sensitive response of the g-C3N4-MnO2 nanocomposite toward H2O2, RTB could be detected sensitively based on the significantly enhanced fluorescent intensity. The linear range of detection was from 0.25 µg mL-1 to 50 µg mL-1 and the limit of detection (LOD) was 190 ng mL-1. Moreover, the proposed assay was successfully applied in the detection of the entire ricin toxin content in a castor seed.


Asunto(s)
Compuestos de Manganeso/química , Nanocompuestos/química , Óxidos/química , Ricina/análisis , Aptámeros de Nucleótidos/química , Ricinus communis/química , Fluorescencia , Transferencia Resonante de Energía de Fluorescencia/métodos , Contaminación de Alimentos/análisis , Glucosa Oxidasa/química , Peróxido de Hidrógeno/química , Límite de Detección , Liposomas , Oligodesoxirribonucleótidos/química , Semillas/química
13.
Pak J Pharm Sci ; 31(2): 447-454, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29618433

RESUMEN

Ganoderma lucidum (Chizhi in Chinese) is one of the most valuable and widely used medicinal fungi in traditional Chinese medicines (TCMs). Most of previous studies were focused on the triterpenoids and polysaccharides of G. lucidum, whereas less attention had been paid on the protein, which is another bioactive compound in it. In the present study, protein maps of fourteen G. lucidum samples were comprehensively analyzed by sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) and two-dimensional electrophoresis (2-DE). The results indicated that there were significant differences in protein profiles of G. lucidum samples from different origins. Furthermore, previous reported bioactive proteins from the fruiting bodies of G. lucidum, were mainly distributed in 4 taxa (A, B, C and D) based on their molecular weights on the 2-DE maps. The proteins should be considered as marker for the quality control of G. lucidum, because the proteomic variation may affect on their pharmacological activities.


Asunto(s)
Electroforesis en Gel de Poliacrilamida/métodos , Proteínas Fúngicas/análisis , Reishi/química , Electroforesis en Gel Bidimensional , Cuerpos Fructíferos de los Hongos/química , Punto Isoeléctrico , Peso Molecular
14.
Anal Chem ; 89(17): 8766-8771, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28737379

RESUMEN

Graphene oxide (GO) has been proven as an outstanding fluorescence anisotropy (FA) amplifier. Yet the traditional GO amplified FA assays lack high sensitivity because of the 1:1 binding ratio between target and dye-modified probe. Herein, we report a new target-catalyzed hairpin assembly (CHA), an enzyme-free DNA circuit, assisted GO amplified FA strategy for microRNA-21 (miRNA-21) detection. In the presence of miRNA-21, the CHA was initiated and plenty of H1-H2 duplexes were produced continuously. The obtained H1-H2 duplex could induce the formation of a H1-H2-probe DNA (pDNA) complex by the toehold-mediated strand exchange reaction, which led the dye-modified pDNA to leave away from the GO surface, resulting in a decreased FA of the system. By monitoring the decrease of FA, miRNA-21 could be detected in the range of 0-16 nM. The limit of detection (LOD, 3σ) was 47 pM, which was 194 times lower than that without CHA. In addition, the selectivity of this method has also been enhanced greatly as compared to that without CHA. Our method has great potential to be applied for detecting different types of targets and monitoring diverse molecular interactions by adapting the corresponding nucleotide sequence.


Asunto(s)
Técnicas Biosensibles/métodos , ADN/química , Grafito/química , MicroARNs/análisis , Espectrometría de Fluorescencia/métodos , Línea Celular Tumoral , ADN/genética , Polarización de Fluorescencia , Células Endoteliales de la Vena Umbilical Humana , Humanos , Secuencias Invertidas Repetidas , Límite de Detección , MicroARNs/genética , Hibridación de Ácido Nucleico , Óxidos/química
15.
Pharm Biol ; 55(1): 76-87, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27653279

RESUMEN

CONTEXT: Corydalis yanhusuo W.T. Wang (Papaveraceae) (Rhizoma Corydalis) showed inhibitory effects on rabbit platelet aggregation induced by ADP, thrombin (THR) or arachidonic acid (AA). OBJECTIVE: This study separates and identifies the possible target-related platelet proteins and suggests possible signal cascades of RC antiplatelet aggregation. MATERIALS AND METHODS: Based on comparative proteomics, the differentially expressed platelet proteins treated before and after with 50 mg/mL RC 90% ethanol extract (for 15 min at 37 °C) were analyzed and identified by two dimensional gel electrophoresis (2-DE) and MALDI-TOF-MS/MS. To further verify the possible signalling pathways of RC antiplatelet aggregation function, the concentration of calcium (Ca2+) was measured by Fura-2/AM fluorescence (Ex 340/380 nm, Em 500 nm) (RC final concentrations of 0.0156-0.1563 mg/mL), the levels of P-selectin and cyclic guanosine monophosphate (cGMP) were quantified by ELISA (OD. 450 nm) (RC final concentrations of 0.0156-1.5625 mg/mL), and the 5-hydroxytryptamine (5-HT) level was measured using ortho-phthalaldehyde (OPT) fluorescence (Ex 340 nm, Em 470 nm) (RC final concentrations of 0.3125-1.5625 mg/mL). RESULTS: The expression of 52 proteins were altered in rabbit platelets after the treatment and the MALDI-TOF-MS analysis indicated that those proteins include 12 cytoskeleton proteins, 7 cell signalling proteins, 3 molecular chaperone proteins, 6 proteins related to platelet function, 16 enzymes and 7 other related proteins. Furthermore, RC extract could decrease the levels of 5-HT [inhibition rate of 96.80% (p < 0.05, vs. THR-activated group) treated with 0.7813 mg/mL of RC], Ca2+ [172.73 ± 5.07 to 113.56 ± 5.46 nM (p < 0.001, vs. THR-activated group) treated with 0.0313 mg/mL of RC] and P-selectin [13.48 ± 0.96 ng/3 × 108 to 11.64 ± 0.17 ng/3 × 108 (p < 0.05, vs. THR-activated group) treated with 0.0156 mg/mL of RC], and increase in cGMP level [38.93 ± 0.57 to 50.26 ± 4.05 ng/3 × 108 (p < 0.05, vs. THR-activated group) treated with 1.5165 mg/mL of RC] in ADP (10 µmol/L), THR (0.25 u/mL) or AA-(0.205 mmol/L) activated rabbit platelets. DISCUSSION AND CONCLUSION: The present study indicated that P2Y12 receptor might be one of the direct target proteins of RC in platelets. The signal cascades network of RC after binding with P2Y12 receptor is mediating Gαi proteins to activate downstream signalling pathways (AC and/or PI3K signalling pathways) for the inhibition of platelet aggregation.


Asunto(s)
Plaquetas/efectos de los fármacos , Corydalis/química , Extractos Vegetales/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Proteómica/métodos , Antagonistas del Receptor Purinérgico P2Y/farmacología , Receptores Purinérgicos P2Y12/efectos de los fármacos , Animales , Plaquetas/metabolismo , Calcio/sangre , GMP Cíclico/sangre , Electroforesis en Gel Bidimensional , Selectina-P/sangre , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Inhibidores de Agregación Plaquetaria/aislamiento & purificación , Antagonistas del Receptor Purinérgico P2Y/aislamiento & purificación , Conejos , Receptores Purinérgicos P2Y12/sangre , Serotonina/sangre , Transducción de Señal/efectos de los fármacos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem
16.
Electrophoresis ; 37(5-6): 736-43, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26541914

RESUMEN

In this paper, an open tubular affinity capillary electrochromatography (OT-ACEC) was developed by physical adsorption of rabbit platelets on the inner surface of capillary. The interactions between small molecules include adenosine diphosphate (ADP) (positive control), protocatechuic acid (negative control) and seven natural products (salvianolic acid B, salvianic acid A sodium, hydroxysafflor yellow A, ferulic acid, chlorogenic acid, sinapic acid, caffeic acid) and platelets were evaluated by their retention factors and binding constants obtained based on peak-shift assay. Then, the activities of anti-platelet aggregation induced by thrombin (THR), ADP and arachidonic acid (AA) for those small molecules (except ADP) were evaluated by turbidimetric method. The results indicate that: (i) ADP, a platelet aggregation inducer, had strong interaction with platelet, while protocatechuic acid that had no inhibition on platelet aggregation behaved no specific interaction; (ii) there was a positive correlation between the anti-platelet aggregation activities of small molecules and their interactions with platelet, generally those compounds with higher binding constants with platelet exhibited higher activities. Therefore, the OT-ACEC method developed in the present study can be a potential method to evaluate affinity interactions between small molecules and platelets, so as to predict the biological activities such as anti-platelet aggregation for the small molecules.


Asunto(s)
Plaquetas/efectos de los fármacos , Electrocromatografía Capilar/métodos , Fármacos Hematológicos/farmacología , Agregación Plaquetaria/efectos de los fármacos , Animales , Plaquetas/citología , Electrocromatografía Capilar/instrumentación , Células Cultivadas , Masculino , Conejos
17.
Pharm Biol ; 54(12): 3113-3120, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27558975

RESUMEN

CONTEXT: The rising problem of atherosclerosis and ischemic heart disease emphasizes the need to look for new antithrombotic components with effective modes of action. Corydalis yanhusuo (Y.H. Chou & Chun C. Hsu) W.T. Wang ex Z.Y. Su & C.Y. Wu (Papaveraceae) (Rhizoma Corydalis) has been used in the traditional medicines for the treatment of cardiovascular disease. OBJECTIVE: The antiplatelet aggregation compounds in Rhizoma Corydalis were screened to validate its traditional medicinal use. MATERIAL AND METHODS: Total alkaloid extract (TAE) of Rhizoma Corydalis was obtained by refluxing 100 g Rhizoma Corydalis powder with 600 mL 70% ethanol, and purified by acidification (20% HCl) and alkalization (5 M NaOH) process. Potential antiplatelet aggregation compounds in TAE were screened by a method involving platelet bio-specific extraction and HPLC-DAD/LC-MS analysis. Further in vitro antiplatelet aggregation activity confirmation of TAE and seven main alkaloids were achieved by turbidimetry method within 3 h after blood collection from rabbit carotid artery, and all the test drugs were at the concentration range of 25-350 µg/mL. Finally, HPLC-DAD was employed for the quantitative determination of seven main components in TAE. RESULTS: Five alkaloids, identified as glaucine, dehydrocorydaline, canadine, tetrahydrocoptisine and corydaline, can be specifically extracted with platelets. The results indicated that all these five alkaloids can inhibit thrombin-induced platelet aggregation in a low dose (IC50 of glaucine, dehydrocorydaline, canadine, tetrahydrocoptisine and corydaline were 49.057, 34.914, 33.547, 84.261 and 54.164 µg/mL, respectively) as compared to TAE (IC50 = 175.426 µg/mL) and aspirin (IC50 = 300.340 µg/mL), while the unbound compounds (palmatine and tetrahydropalmatine) had a very weak antiplatelet effect (IC50 > 200 µg/mL). DISCUSSION AND CONCLUSION: This study is the first reported work for antiplatelet components screening in Rhizoma Corydalis. Seven compounds were detected and identified by HPLC-DAD/LC-MS, of which five platelet-targeted compounds were discovered.


Asunto(s)
Alcaloides/análisis , Corydalis , Extractos Vegetales/análisis , Inhibidores de Agregación Plaquetaria/análisis , Agregación Plaquetaria/efectos de los fármacos , Rizoma , Alcaloides/farmacología , Animales , Extractos Vegetales/farmacología , Agregación Plaquetaria/fisiología , Inhibidores de Agregación Plaquetaria/farmacología , Conejos
18.
Zhongguo Zhong Yao Za Zhi ; 40(13): 2508-17, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26697671

RESUMEN

As one of the important active components of traditional Chinese medicine (TCM), plant origin active proteins have many significant pharmacological functions. According to researches on the plant origin active proteins reported in recent years, pharmacological effects include anti-tumor, immune regulation, anti-oxidant, anti-pathogeny microorganism, anti-thrombus, as well as hypolipidemic and hypoglycemic activities of plant origin were reviewed, respectively. On the other hand, the analytical methods including chromatography, spectroscopy, electrophoresis and mass spectrometry for plant origin proteins analysis were also summarized. The main purpose of this paper is providing a reference for future development and application of plant active proteins.


Asunto(s)
Proteínas de Plantas/análisis , Proteínas de Plantas/farmacología , Animales , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Fibrinolíticos/farmacología , Humanos , Hipoglucemiantes/farmacología , Factores Inmunológicos/farmacología , Investigación
19.
Therap Adv Gastroenterol ; 17: 17562848241284229, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39386273

RESUMEN

Background: Fruquintinib is a third-line and subsequent targeted therapy for patients with metastatic colorectal cancer (mCRC). Identifying survival predictors after fruquintinib is crucial for optimizing the clinical use of this medication. Objectives: We aimed to identify factors influencing the prognosis of patients with mCRC treated with fruquintinib and to leverage these insights to develop a nomogram model for estimating survival rates in this patient population. Design: Multicenter retrospective observational study. Methods: We collected patient data from January 2019 to October 2023, with one healthcare institution's data serving as the training cohort and the other three hospitals' data serving as the multicenter validation cohort. The nomogram for overall survival was calculated from Cox regression models, and variable selection was screened using the univariate Cox regression analysis with additional variables based on clinical experience. Model performance was measured by the concordance index (C-index), calibration curves, decision curve analyses (DCA), and utility (patient stratification into low-risk vs high-risk groups). Results: Data were ultimately collected on 240 patients, with 144 patients included in the training cohort and 96 included in the multicenter validation cohort. Predictors included in the nomogram were CA199, body mass index, T stage, the primary site of the tumor, and other metastatic and pathological differentiation. The C-index of the nomogram in the training set and multicenter validation was 0.714 and 0.729, respectively. The models were fully calibrated and their predictions aligned closely with the observed data. DCA curves indicated the promising clinical benefits of the predictive model. Finally, the reliability of the model was also verified through the risk classification using the nomogram. Conclusions: We constructed a nomogram for mCRC treated with fruquintinib based on six variables that may be used to assist in personalizing the use of the drug.


A nomogram for predicting OS after application of fruquintinib in patients with mCRC The prognostic predictors of fruquintinib as a third-line and subsequent treatment agent for patients with mCRC have not been established. In this study, we explored possible factors influencing its prognosis and developed a nomogram model for estimating survival rates in this patient population. The nomogram, based on six key variables including CA199, BMI, T stage, primary tumor site, other metastatic sites, and pathological differentiation, was validated through a rigorous multicenter validation process. The nomogram has the potential to help clinicians personalize the use of fruquintinib for mCRC patients.

20.
Zhongguo Zhong Yao Za Zhi ; 38(16): 2682-9, 2013 Aug.
Artículo en Zh | MEDLINE | ID: mdl-24228587

RESUMEN

To establish a new method of quality evaluation of Traditional Chinese medicine by fingerprint and quantitative analysis of multi-components by single marker method (QAMS). The quality evaluation method was established and validated with Houttuyniae Herba. Chlorogcnic acid was selected as markers of ingredients to establish HPLC fingerprint and internal reference standard to determine the contents of other 6 components (new chlorogcnic acid, cryptochlorogenic acid, rutin, hyperin, isoquercitrin, quercitrin) according to the relative correction factor. At the same time, the seven components were determined by external standard method. The accuracy and feasibility of QAMS was evaluated by comparison of the results between external standard method and QAMS. All tested samples contained the 12 common peaks , 7 of which was verified ,and there was no significant differences between the quantitative results of 7 ingredients of multi-components by single marker method and external standard method in 20 batches. The method of fingerprint combined with QAMS has been verified in Houttuyniae Herba and it is to be a new quality evaluation pattern for Traditional Chinese medicine.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/análisis , Cromatografía Líquida de Alta Presión/normas , Medicamentos Herbarios Chinos/química , Houttuynia , Control de Calidad , Reproducibilidad de los Resultados
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