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1.
Medicine (Baltimore) ; 100(39): e27197, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34596117

RESUMO

BACKGROUND: Administering corticosteroid is an effective therapeutic strategy for treating most inflammatory conditions. However, there is a chance for corticosteroid treatment to adversely affect bones, resulting in corticosteroid-induced osteoporosis, which is a highly prevalent type of secondary osteoporosis. Elevated bone resorption and reduced formation of bone are pathogenesis indicators of corticosteroid-induced osteoporosis. Preventative therapy is recommended for patients initiating steroids. This study aims to evaluate the efficiency of calcium and vitamin D in treating adults diagnosed with osteoporosis caused by corticosteroid therapy. METHODS: Electronic databases will be searched systematically to source studies that have evaluated the efficiency of calcium and vitamin D as a treatment method for adult patients with osteoporosis from corticosteroid therapy. The databases include, PubMed, EMBASE, the Cochrane Library, Scopus, and Web of Science. The timeline of the search will be limited from inception to November 2020. This study will utilize the Cochrane risk of bias tool to assess the quality of the studies reviewed. Moreover, appropriate methods will be chosen to analyze the data. The RevMan 5.3 software is utilized to perform statistical analysis. RESULTS: This study will provide additional practical and targeted results of evaluating the efficiency of calcium and vitamin D in treating adults with corticosteroid-induced osteoporosis. CONCLUSION: The results of this study will provide further evidence about calcium and vitamin D in treating adults with corticosteroid-induced osteoporosis, clinicians and policymakers can make practical use of the results. ETHICS AND DISSEMINATION: Since this systematic review does not involve any human or animal participants, an ethics approval is not required. SYSTEMATIC REVIEW REGISTRATION: Aug 19, 2021. osf.io/zvb38. (https://osf.io/zvb38/).


Assuntos
Corticosteroides/efeitos adversos , Cálcio/uso terapêutico , Metanálise como Assunto , Osteoporose/induzido quimicamente , Osteoporose/tratamento farmacológico , Projetos de Pesquisa , Revisões Sistemáticas como Assunto/métodos , Vitamina D/uso terapêutico , Adulto , Humanos , Resultado do Tratamento
2.
Anal Chim Acta ; 1154: 338319, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736800

RESUMO

Protein is an excellent molecular mass amplifier without fluorescence quenching effect for fluorescence anisotropy (FA) assay. However, in traditional protein amplified FA methods, the binding ratio between amplifier and dye-modified probe is 1:1 or one target can only induce FA change of one fluorophore on probe, resulting in low sensitivity. Herein, we developed a simple FA strategy with high accuracy and sensitivity by using a crosslinked submicro-hydrogel that was formed through a catalyzed hairpin assembly (CHA) assisted protein aggregation as a novel FA amplifier. In the presence of catalyst, the CHA process was initiated through the toehold-mediated strand exchange reaction, which led to the formation of a dye and biotin-labeled Y-shaped H1-H2 duplex (YHD) and recycling of catalyst. With the introduction of streptavidin, a crosslinked submicro-hydrogel was formed by strong binding affinity between biotin on YHD and streptavidin, resulting in an increased FA of fluorescent dye. After rational design of the catalyst sequence, this method has been utilized for the detection of miRNA-145, staphylococcal enterotoxin B (SEB) and ATP with an LOD of 2.5 nM, 92 pg mL-1 and 3.6 µM, respectively. Moreover, this FA assay has been successfully applied for direct detection of target in biological samples, demonstrating its practicality in complex biological systems.


Assuntos
Técnicas Biossensoriais , Agregados Proteicos , DNA , Polarização de Fluorescência , Hidrogéis , Limite de Detecção
3.
Chem Commun (Camb) ; 57(26): 3211-3214, 2021 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-33644788

RESUMO

Here we report a chirality transfer of cysteine, which at first was to the plasmonic resonance region of gold nanobipyramids and then to that of Ag nanoshells with increasing growth of Ag layers, owing to the important role of the free Cys embedded within the Ag nanoshell. Our finding is helpful for developing new chiral plasmonic nanomaterials with the best designed asymmetric properties.

4.
Anal Bioanal Chem ; 413(9): 2457-2466, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33674935

RESUMO

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.


Assuntos
Fosfatase Alcalina/metabolismo , Técnicas Biossensoriais/métodos , Glicemia/análise , Ensaios Enzimáticos/métodos , Fosfatase Alcalina/antagonistas & inibidores , Técnicas Biossensoriais/instrumentação , Ensaios Enzimáticos/instrumentação , Inibidores Enzimáticos/farmacologia , Desenho de Equipamento , Humanos , Modelos Moleculares
5.
Anal Chem ; 93(7): 3526-3534, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33562958

RESUMO

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.


Assuntos
Nanotubos , Neoplasias , Telomerase , Animais , DNA , Transferência Ressonante de Energia de Fluorescência , Camundongos , Neoplasias/tratamento farmacológico , Fosfoproteínas , Proteínas de Ligação a RNA , Telomerase/genética , Telomerase/metabolismo
6.
Anal Chem ; 93(7): 3411-3417, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33565859

RESUMO

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.

7.
Virol J ; 18(1): 22, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33461581

RESUMO

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.


Assuntos
Células Epiteliais Alveolares/virologia , Autofagia/genética , Regulação da Expressão Gênica , Vírus da Influenza A Subtipo H9N2/fisiologia , Infecções por Orthomyxoviridae/veterinária , Estresse Oxidativo/genética , Replicação Viral , Células A549 , Animais , Humanos , Vírus da Influenza A Subtipo H9N2/patogenicidade , Transdução de Sinais , Suínos
8.
ACS Nano ; 14(10): 14134-14145, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33044056

RESUMO

Flexible and lightweight high-performance electromagnetic interference shielding materials with minimal thickness, excellent mechanical properties, and outstanding reliability are highly desired in the field of fifth-generation (5G) communication, yet remain extremely challenging to manufacture. Herein, we prepared an ultrathin densified carbon nanotube (CNT) film with superior mechanical properties and ultrahigh shielding effectiveness. Upon complete removal of impurities in pristine CNT film, charge separation in individual CNTs induced by polar molecules leads to strong CNT-CNT attraction and film densification, which significantly improve the electrical conductivity, shielding performance, and mechanical strength. The tensile strength is up to 822 ± 21 MPa, meanwhile the electrical conductivity is as high as 902,712 S/m, and the density is only 1.39 g cm-3. Notably, the shielding effectiveness is over 51 dB with a thickness of merely 1.85 µm in the broad frequency range of 4-18 GHz, and it reaches to ∼82 dB at 6.36 µm and ∼101 dB at 14.7 µm, respectively. Further, such CNT film exhibits excellent reliability after an extended period in strong acid/alkali, high temperature, and high humidity. It demonstrates the best overall performance among representative shielding materials by far, representing a critical breakthrough in the preparation of shielding film toward applications in wearable electronics and 5G communication.

9.
Acta Virol ; 64(4): 496-500, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32985209

RESUMO

 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.


Assuntos
Evolução Molecular , Genoma Viral , Filogenia , SARS-CoV-2/genética , Animais , COVID-19 , China , Humanos
10.
J Chromatogr Sci ; 58(9): 875-879, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32789472

RESUMO

In the present study, an online liquid extraction coupled with high-performance liquid chromatography-2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (HPLC-ABTS) system for rapid screening of antioxidants in tea samples was proposed. As an example, the tea samples were firstly extracted by online HPLC extractor with mobile phase at 70°C, then the hyphenated HPLC-ABTS was used for the chromatographic separation on a Poroshell EC C18 column by 0.3% aqueous formic acid and acetonitrile with a gradient elution at 1.5 mL·min-1, and the UV and antioxidant chromatograms with detection wavelengths at 270 nm and 750 nm were recorded, respectively. The established system integrated the processes of online HPLC sample extraction, HPLC separation and online antioxidants detection, the total analysis time of which was <20 min. The developed method was successfully applied to samples of green tea, oolong tea and black tea. As a result, 11 antioxidants were found in tea samples, including gallocatechin, epigallocatechin, catechin, chlorogenic acid, epicatechin, epigallocatechingallate, epicatechingallate, rutin, 1,4,6-trigalloylglucose, quercetin-3-glycoside and kaempferol-3-glucoside. The combined online liquid microextraction and online HPLC-ABTS method is a rapid and green approach for the quality evaluation of tea.


Assuntos
Antioxidantes/análise , Camellia sinensis/química , Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Líquida/métodos , Chá/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis , Reprodutibilidade dos Testes , Ácidos Sulfônicos
11.
Vet Microbiol ; 246: 108747, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32605760

RESUMO

H9N2 avian influenza viruses (AIVs) can cross species barriers and expand from birds tomammals and humans. It usually leads to economic loss for breeding farms and poses a serious threat to human health.This study investigated the molecular characteristics of H9N2 AIV isolated from a racing pigeon and its pathogenesis in BALB/c mice and pigeons. Phylogenetic analysis indicated that the H9N2 virus belonged to the Ck/BJ/94-like lineage, and acquired multiple specific amino acid substitutions that might contribute to viral transmission from birds to mammals and humans. A pathogenesis study showed that both mice and pigeons infected with H9N2 virus showed clinical signs and mortality. The H9N2 viruses efficiently replicated in mice and pigeons. In our study, high levels of viral shedding were detected in pigeons, but the infection was not transmitted to co-housed pigeons. Histopathological examination revealed the presence of inflammatory responses in the infected mice and pigeons. Immunohistochemical analysis showed the presence of H9N2 virus in multiple organs of the infected mice and pigeons. Moreover, the infected mice and pigeons demonstrated significant cytokine/chemokine production. Our results showed that the H9N2 virus can infect mice and pigeons, and can not be transmitted between pigeons through direct contact.


Assuntos
Columbidae/virologia , Genoma Viral , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Aviária/virologia , Substituição de Aminoácidos , Animais , Quimiocinas/imunologia , Citocinas/imunologia , Feminino , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Influenza Aviária/transmissão , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Filogenia , Organismos Livres de Patógenos Específicos , Replicação Viral , Eliminação de Partículas Virais
12.
Talanta ; 211: 120730, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32070579

RESUMO

Recently, various inorganic nanomaterials have been used as fluorescence anisotropy (FA) enhancers for biosensing successfully. However, most of them are size-uncontrollable and possess an intensive fluorescence quenching ability, which will seriously reduce the accuracy and sensitivity of FA method. Herein, we report a two-dimensional DNA nanosheet (DNS) without fluorescence quenching effect as a novel FA amplification platform. In our strategy, fluorophore-labeled probe DNA (pDNA) is linked onto the DNS surface through the hybridization with the handle DNA (hDNA) that extended from the DNS, resulting in the significantly enhanced FA value. After the addition of target, the pDNA was released from the DNS surface due to the high affinity between the hDNA and target, and the FA was decreased. Thus, target could be detected by the significantly decreased FA value. The linear range was 10-50 nM and the limit of detection was 8 nM for the single-stranded DNA detection. This new method is general and has been also successfully applied for the detection of ATP and thrombin sensitively. Our method improved the accuracy of FA assay and has great potential to detect series of biological analytes in complex biosensing systems.


Assuntos
Trifosfato de Adenosina/análise , Técnicas Biossensoriais/métodos , DNA/química , Polarização de Fluorescência/métodos , Corantes Fluorescentes/química , Nanoestruturas/química , Trombina/análise , DNA de Cadeia Simples/análise , Humanos , Limite de Detecção , Hibridização de Ácido Nucleico , Espectrometria de Fluorescência
13.
Luminescence ; 35(2): 222-230, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31713314

RESUMO

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.


Assuntos
Carbono/metabolismo , Carcinoma Hepatocelular/diagnóstico por imagem , Inibidores de Glicosídeo Hidrolases/farmacologia , Neoplasias Hepáticas/diagnóstico por imagem , Pontos Quânticos/metabolismo , beta-Glucosidase/antagonistas & inibidores , beta-Glucosidase/análise , Carbono/química , Fluorescência , Inibidores de Glicosídeo Hidrolases/química , Células Hep G2 , Humanos , Imagem Óptica , Pontos Quânticos/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Células Tumorais Cultivadas , beta-Glucosidase/metabolismo
14.
Int Immunopharmacol ; 74: 105737, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31288152

RESUMO

Influenza A virus usually leads to economic loss to breeding farms and pose a serious threat to human health. Virus infecting tissues directly and influenza virus-induced excessive production of inflammatory factors play the key role in pathogenesis of the disease, but the mechanism is not well clarified. Here, the role of autophagy was investigated in H9N2 influenza virus-triggered inflammation. The results showed that autophagy was induced by H9N2 virus in A549 cells and in mice. Inhibiting autophagy by an autophagy inhibitor (3-methyladenine, 3-MA) or knockdown of Atg5(autophagy-related gene) by Atg5 siRNA significantly suppressed H9N2 virus replication, H9N2 virus-triggered inflammatory cytokines and chemokines, including IL-1ß, TNF-α, IL-8, and CCL5 in vitro and in vivo, and suppressed H9N2 virus-triggered acute lung injury as indicated as accumulative mortality of mice, inflammatory cellular infiltrate and interstitial edema, thickening of the alveolar walls in mice lung tissues, increased inflammatory cytokines and chemokines, increased W/D ratio in mice. Moreover, autophagy mediated inflammatory responses through Akt-mTOR, NF-κB and MAPKs signaling pathways. Our data showed that autophagy was essential in H9N2 influenza virus-triggered inflammatory responses, and autophagy could be target to treat influenza virus-caused lung inflammation.


Assuntos
Lesão Pulmonar Aguda/imunologia , Proteína 5 Relacionada à Autofagia/metabolismo , Autofagia/genética , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Humana/imunologia , Infecções por Orthomyxoviridae/imunologia , Células A549 , Animais , Proteína 5 Relacionada à Autofagia/genética , Citocinas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , RNA Interferente Pequeno/genética , Transdução de Sinais
15.
Zhongguo Zhong Yao Za Zhi ; 44(10): 1978-1982, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31355550

RESUMO

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.


Assuntos
Cromatografia Líquida de Alta Pressão , Cordyceps/química , Ergosterol/análise , Nucleosídeos/análise
16.
Zhongguo Zhong Yao Za Zhi ; 44(10): 1983-1988, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31355551

RESUMO

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.


Assuntos
Cordyceps/química , Dessecação/métodos , Proteínas Fúngicas/análise , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Peso Molecular
17.
Artigo em Inglês | MEDLINE | ID: mdl-31176269

RESUMO

Plant polyphenols can form functional coatings on various materials through self-polymerization. In this paper, a series of modified capillary columns, which possess diversity of charge characteristics for modulating electroosmotic flow (EOF), were prepared by one-step co-deposition of gallic acid (GA), a plant-derived polyphenol monomer, and branched polyethyleneimine (PEI). The physicochemical properties of the prepared columns were characterized by Fourier transform infrared spectroscopy (FT-IR), UV-Vis spectroscopy and scanning electron microscopy (SEM). The magnitude and direction of EOF of GA/PEI co-deposited columns were modulated by changing a series of coating parameters, such as post-incubation of FeCl3, co-deposition time, and deposited amounts of GA and PEI with different relative molecular mass (PEI-600, PEI-1800, PEI-10000, and PEI-70000). Furthermore, the separation efficiencies of the prepared GA/PEI co-deposited columns were evaluated by separations of small molecules, including organic acids, polar nucleotides, phenols, nucleic acid bases and nucleosides. Results indicated that modulating of EOF plays an important role in enhancing the separation performance and reversing the elution order of the analytes. Finally, the developed method was successfully applied to quantitative analysis of acidic compounds in four real samples. The recoveries were in the range of 73.5%-85.8% for citric acid, benzoic acid, sorbic acid, salicylic acid and ascorbic acid in beverage and fruit samples, 101.6%-104.9% for cinnamic acid, vanillic acid, and ferulic acid in Angelica sinensis sample, while 84.6%-97.8% for guanosine-5'-monophosphate, uridine-5'-monophosphate, cytosine-5'- monophosphate and adenosine-5'-monophosphate in Cordyceps samples. These results indicated that the co-deposition of plant polyphenol-inspired GA/PEI coatings can provide new opportunities for EOF modulation of capillary electrophoresis.


Assuntos
Eletrocromatografia Capilar/métodos , Eletro-Osmose/métodos , Ácido Gálico/química , Polietilenoimina/química , Eletrocromatografia Capilar/instrumentação , Eletro-Osmose/instrumentação , Peso Molecular , Ácidos Nucleicos/isolamento & purificação , Nucleosídeos/isolamento & purificação , Nucleotídeos/isolamento & purificação , Compostos Orgânicos/isolamento & purificação , Polimerização
18.
Chem Commun (Camb) ; 55(45): 6437-6440, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31095140

RESUMO

A precise ricin A-chain (RTA) delivery system was constructed by coupling RTA to carbon dots (CDs) with a distinctive capacity for Golgi targeting. The rational design shows efficient internalization and an exact pathway to the cytoplasm for RTA to exert its real toxic action since it could avoid lysosome degradation.


Assuntos
Carbono/química , Sistemas de Liberação de Medicamentos , Complexo de Golgi/química , Pontos Quânticos/química , Ricina/química , Citoplasma/química , Citoplasma/metabolismo , Complexo de Golgi/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Ricina/toxicidade
19.
Anal Chem ; 91(10): 6761-6768, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31020834

RESUMO

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.


Assuntos
Corantes Fluorescentes/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Pontos Quânticos/química , Linhagem Celular , DNA/química , DNA/genética , DNA/toxicidade , Corantes Fluorescentes/toxicidade , Ouro/química , Ouro/toxicidade , Humanos , Limite de Detecção , Nanopartículas Metálicas/toxicidade , MicroRNAs/genética , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hibridização de Ácido Nucleico , Pontos Quânticos/toxicidade
20.
Pak J Pharm Sci ; 32(1): 185-195, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30772808

RESUMO

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).


Assuntos
Sucos de Frutas e Vegetais , Frutas , Extratos Vegetais/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Verduras , Animais , Relação Dose-Resposta a Droga , Frutas/química , Masculino , Extratos Vegetais/isolamento & purificação , Inibidores da Agregação Plaquetária/isolamento & purificação , Testes de Função Plaquetária , Coelhos , Verduras/química
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