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1.
Phytomedicine ; 65: 153103, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31805425

RESUMO

BACKGROUND: Regulation of the survival and differentiation of bone marrow mesenchymal stem cells is an essential consideration in the development of targeted drugs for treatment of osteoporosis. PURPOSE: The present study aimed to evaluate the combined effect of wedelolactone and oleonuezhenide, two compounds from Chinese formula Er-Zhi-Wan, on osteoblastogenesis and the underlying molecular mechanisms. METHODS: MTT assay was taken to evaluate cell proliferation. The alkaline phosphatase (ALP) activity assay was used to determine the activity of ALP. Alizarin red S (ARS) staining was taken to indicate the intensity of the calcium deposits. Quantitative real-time PCR and Western blot were performed to the levels of Runx2, Osteocalcin, and Osterix expression in mouse bone marrow mesenchymal stem cells (BMSCs). Ovariectomized mouse model and bone histomorphometric analysis were also used to research the effects of wedelolactone and oleonuezhenide on bone loss caused by ovariectomy. RESULTS: Wedelolactone combined with oleonuezhenide enhanced osteoblast differentiation and bone mineralization. Osteoblastogenesis-related marker genes including osteocalcin, Runx2, and osteorix were upregulated in the presence of wedelolactone and oleonuezhenide. At the molecular level, oleonuezhenide did not affect GSK-3ß phosphorylation induced by wedelolactone, but elevated casein kinase 2-alpha (CK2α) expression, resulting in ß-catenin and Runx2 nuclear translocation. In addition, 30 µM wedelolactone-induced cytotoxicity in bone marrow mesenchymal stem cells was relieved by 9 µM oleonuezhenide. These cells were protected by oleonuezhenide and maintained osteoblastic activity. Oleonuezhenide increased Wnt5a and CK2α expression. Wedelolactone-reduced extracellular signal-regulated kinase (ERK) phosphorylation was reversed by oleonuezhenide. In ovariectomized mice, administration of wedelolactone and oleonuezhenide prevented ovariectomy-induced bone loss by enhancing osteoblastic activity. CONCLUSION: These results suggested that oleonuezhenide enhanced the effects of wedelolactone on osteoblastogenesis. These two compounds could be developed as a combined therapeutic agent for osteoporosis.

2.
Biosens Bioelectron ; : 111917, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31784310

RESUMO

This paper introduces a paper-based closed Au-bipolar electrode (BPE) biosensing system for the rapid and sensitive electrochemiluminescence (ECL) detection of miRNA-155. This microfluidic paper-based sensing platform is formed by wax-printing technology, screen printing method and in-situ Au nanoparticles (NPs) growth to form hydrophilic cells, hydrophobic boundaries, water proof electronic bridge, driving electrode regions and bipolar electrode regions. For rapid and sensitive detection, the cathode of bipolar electrode was modified with the prepared DNA (S1)-AuPd NPs by hybridization chain reaction, in which the target could initiate multiple cycles reaction to load more AuPd NPs which catalyzed H2O2 reduction. In addition, a classical ECL system tris (2,2'-bipyridine) ruthenium (II)- tripropylamine (Ru(bpy)32+/TPrA) exists at the anode of the bipolar electrode. Due to the charge balance between the anode and the cathode of BPE, the ECL signal response of Ru(bpy)32+/TPrA system was enhanced in the reporting cell. The intensity of ECL was quantitatively correlated with the concentration of miRNA-155 in the range of 1 pM-10 µM with the detection limit 0.67 pM. Moreover, this method paves a novel way for highly sensitive detection of miRNA-155 in clinical application.

3.
EMBO Rep ; : e47528, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31797533

RESUMO

SAMHD1 possesses multiple functions, but whether cellular factors regulate SAMHD1 expression or its function remains not well characterized. Here, by investigating why cultured RD and HEK293T cells show different sensitivity to enterovirus 71 (EV71) infection, we demonstrate that SAMHD1 is a restriction factor for EV71. Importantly, we identify TRIM21, an E3 ubiquitin ligase, as a key regulator of SAMHD1, which specifically interacts and degrades SAMHD1 through the proteasomal pathway. However, TRIM21 has no effect on EV71 replication itself. Moreover, we prove that interferon production stimulated by EV71 infection induces increased TRIM21 and SAMHD1 expression, whereas increasing TRIM21 overrides SAMHD1 inhibition of EV71 in cells and in a neonatal mouse model. TRIM21-mediated degradation of SAMHD1 also affects SAMHD1-dependent restriction of HIV-1 and the regulation of interferon production. We further identify the functional domains in TRIM21 required for SAMHD1 binding and the ubiquitination site K622 in SAMHD1 and show that phosphorylation of SAMHD1 at T592 also blocks EV71 restriction. Our findings illuminate how EV71 overcomes SAMHD1 inhibition via the upregulation of TRIM21.

4.
Medicine (Baltimore) ; 98(50): e18304, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852111

RESUMO

The differential diagnosis of Crohn disease (CD) from intestinal tuberculosis (ITB) and primary intestinal lymphoma (PIL) is challenging in patients who exhibit atypical clinical characteristics. The aim of the present study was to explore the serum proteome profiles of CD, PIL and ITB and to identify their differentiations.Treatment-naïve patients with CD (n = 10), PIL (n = 10) and ITB (n = 10) were enrolled in the present study. Differentially expressed proteins (DEPs) in patient serum samples were compared between groups using tandem mass tag labeled proteomic technology. A principal component analysis (PCA) plot and volcano maps were also visualized. Functional pathway analysis was performed using Reactome. The Area under the Curve (AUC) was calculated for each DEP.A total of 818 proteins were identified through proteomic quantification. Among them, 108 DEPs were identified to be differentiated between CD and ITB, 105 proteins between CD and PIL and 55 proteins between ITB and PIL. The proteome from the three groups was distinguishable in the PCA plot. The results revealed that 19, 12, and 10 proteins (AUC ≥ 0.95) were differentially expressed between CD and PIL, CD and ITB, and PIL and ITB, respectively. Among these DEPs, tumor necrosis factor ligand superfamily member 13 was higher in CD than in ITB and PIL. Peroxiredoxin-5, T-complex protein 1 subunit Gamma, CutA, and Fibulin-5 were increased in CD and PIL when compared with ITB. The levels of fibrinogen chains were also significantly higher in patients with PIL compared with CD.The current study demonstrated that serum proteome was distinguishable among patients with CD, PIL, and ITB. The identified proteins may assist in the clinical differentiation among them.


Assuntos
Doença de Crohn/diagnóstico , Neoplasias Intestinais/sangue , Linfoma/sangue , Proteoma/análise , Proteômica/métodos , Tuberculose Gastrointestinal/sangue , Adulto , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Neoplasias Intestinais/diagnóstico , Linfoma/diagnóstico , Masculino , Espectrometria de Massas , Projetos Piloto , Estudos Retrospectivos , Tuberculose Gastrointestinal/diagnóstico
5.
J Sci Food Agric ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31858597

RESUMO

BACKGROUND: Koumiss is a traditional fermented beverage made from mare's milk. The traditional backslopping method for koumiss production has shortcomings in terms of microbiological diversity and nutritional characteristics. In this study, a two-stage fermentation method was established to scale up the production of koumiss powder. The chemical composition and nutritional properties of a novel two-stage fermentation koumiss powder (TKP) were compared with backslopping koumiss powder (BKP). RESULTS: The TKP exhibited important nutritional and functional properties, including a high percentage of essential amino acids, and high polyunsaturated fatty acid, vitamin, and mineral content. The essential amino acid content of TKP was not significantly different from that of BKP. The oleic acid, linoleic acid, linolenic acid, and water-soluble vitamin content of TKP was higher than that of BKP. The Ca:P ratio of TKP was also close to the optimal Ca:P ratio in humans. CONCLUSION: The novel method could be applied for the scaled-up production of koumiss powder with similar nutritional properties to traditional backslopping koumiss powder. The successful production of koumiss powder could also promote the development of the koumiss industry. © 2019 Society of Chemical Industry.

6.
Biomed Res Int ; 2019: 1475705, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886172

RESUMO

Tenascin-C (TNC) is an extracellular matrix glycoprotein expressed in response to inflammation and tissue damage. The role of TNC in patients with inflammatory bowel disease (IBD) is not well understood. In this study, we analyzed the expression of TNC in the inflamed mucosa of patients with ulcerative colitis (UC) and Crohn's disease (CD). Serum TNC levels were determined by the enzyme-linked immunosorbent assay (ELISA), and the levels of TNC in patients with different disease activities were compared. The expression of TNC was derived from a GEO dataset. THP-1 cells were stimulated with TNC to evaluate the proinflammatory role of TNC. We found higher TNC expression in the inflamed mucosa of patients with UC and CD compared with normal controls (NCs). TNC was mainly expressed in the stromal area of the intestinal mucosa. The median serum levels of TNC were significantly higher in UC (median 74.1 ng/ml, range 42.6-102.1 ng/ml) and CD (median 59.2 ng/ml, range 44.0-80.9 ng/ml). We also found that serum TNC levels were correlated with Mayo scores in UC and Crohn's disease activity index (CDAI) in CD. Through GSE14580, we demonstrated that patients who were nonresponsive to infliximab treatment had higher mucosal TNC mRNA expression. High TNC mRNA expression in the inflamed intestinal mucosa was associated with poor response to infliximab therapy in patients with UC. Furthermore, THP-1 cells stimulated with TNC showed increased expression of IL-6, but not TNF-α, IL-8, MCP-1, or IL-1ß. Thus, increased TNC levels may participate in the pathogenesis of IBD and may serve as a biomarker for disease activity and response to treatment with infliximab.

7.
Anal Chem ; 91(22): 14577-14585, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31631655

RESUMO

Integrating ratiometric photoelectrochemical (PEC) techniques with paper microfluidics to construct a ratiometric PEC paper analytical device for practical application is often restricted by the grave dependence of ratiometric assay on photoactive materials and low mass-transfer rates of the paper channel. Herein, a universal donor/acceptor-induced ratiometric PEC paper analytical device with a hollow double-hydrophilic-walls channel (HDHC) was fabricated for high-performance microRNA-141 (miRNA-141) quantification. Concretely, a photoanode and photocathode were integrated on the paper-based sensing platform in which the photocathode served as a biosensing site for the pursuit of higher selectivity. For formulation of a cascading signal amplification strategy, a unique duplex-specific nuclease-induced target recycling reaction was engineered for the output of a double amount of all useful DNA linkers instead of conventional output of only one available DNA product, which could guarantee the output of abundant DNA linkers with the initiation of a cascade of hybridization chain reaction on both the trunk and branch in the presence of miRNA-141. Then the formed dendriform polymeric DNA duplex structures were further decorated with glucose oxidase (GOx)-mimicking gold nanoparticles by the electrostatic interaction to form a branchy gold tree (BGT). Profiting from the perfect GOx-mimicking activity of BGT and high mass-transfer rates of HDHC, the cathodic photocurrent from Ag2S/Cu2O hybrid structure was in a "signal off" state while the anodic photocurrent from graphene quantum dots (GQDs) and Ag2Se QDs cosensitized ZnO nanosheets was in a "signal on" state because BGT-catalyzed glucose oxidation reaction evoked the consumption of dissolved O2 as an electron acceptor and the generation of H2O2 as an electron donor. With calculation of the ratio of two photocurrent intensities, the quantitative detection of miRNA-141 was achieved with high sensitivity, accuracy, and reliability.

8.
ACS Appl Mater Interfaces ; 11(44): 41062-41068, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31597416

RESUMO

A wide-spectrum-responsive paper-based photoelectrochemical (PEC) sensor based on black phosphorus (BP) quantum dots (QDs)-sensitized titanium dioxide (TiO2-BP QDs) for prostate-specific antigen (PSA) detection was presented herein. Carbon nanotubes (CNTs) were first coated on paper to form a flexible conductive paper electrode. TiO2 nanoparticles were then in situ synthesized on the CNTs-modified paper working electrode with direct liquid-phase hydrolysis with normal temperature, shirtsleeve operation, and gentle solution. Meanwhile, BP QDs, derived from two-dimensional BP nanosheets, can harvest light from the ultraviolet to near-infrared region, broaden efficient utilization of light, add a new dimension to BP research, and impel the high expectation on the potentials of QDs. To implement an assay protocol, exciton-plasmon interactions between TiO2-BP QDs and gold nanoparticles were introduced into the PEC sensing platform for high sensitivity detection of the PSA antigen. Under the optimal conditions, this proposed method exhibited a linear response ranging from 0.005 to 50 ng/mL with a detection limit of 1 pg/mL. This sensing protocol offered a promising analytical method with favorable properties of high selectivity, stability, and reproducibility.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31650411

RESUMO

Previous studies have shown increased risk of herpes zoster (HZ) infection in patients with inflammatory bowel disease (IBD). The aim of this study is to better characterize this possible association by conducting a meta-analysis. A comprehensive search of relevant literature until April 30, 2019, was performed. Data on HZ infection and medications in patients with IBD and controls were extracted. The relative risk (RR) and 95% confidence interval (CI) were calculated. Subgroup analyses were performed to assess the source of heterogeneity. Seven cohort studies were included that involved more than 1,000,000 participants. The RR of HZ infection in patients with Crohn's disease (CD) compared with non-CD patients was 1.74 (95% CI 1.57-1.92, p < 0.001). The pooled RR of HZ infection in patients with ulcerative colitis (UC) compared with non-UC was 1.40 (95% CI 1.31-1.50, p < 0.001). Subgroup analyses revealed that age, race, and publication year contribute to heterogeneity. We also found that steroid users were at increased risk of HZ in CD (OR = 1.78, 95% CI 1.10-2.88). Steroid users and anti-TNFα users were at increased risk of HZ in UC, with RRs of 1.99 (95% CI 1.64-2.42) and 2.29 (95% CI 1.52-3.45), respectively. Begg's test and Egger's test suggested no publication bias. There was a 74% increased risk of HZ infection in patients with CD and 40% increased risk of HZ infection in patients with UC compared with that in non-IBD. IBD patients with high risk of HZ infection may benefit from an HZ vaccine.

10.
J Hazard Mater ; : 121426, 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31635817

RESUMO

The prevalence of Internet of Things and portable electronics create an unprecedented demand for the high performance gas sensors. To pursuit such sensor, sandwich-type (phthalocyaninato)(porphyrinato) europium double-decker complex Eu(TPyP)(Pc) [TPyP = meso-tetra(4-pyridyl)porphyrin; Pc = phthalocyanine] was in situ self-assembled on the surface of reduced graphene oxide (rGO) driven by the π-π interaction, forming a 3D synergistical rGO/Eu(TPyP)(Pc) hybrid aerogel. The resulting aerogel not only effectively integrates the gas sensing of Eu(TPyP)(Pc) and good conductivity of rGO, but also exhibited a prominent synergy effect. Ascribed to the attractive properties, the fabricated NO2 gas sensor exhibits superior sensitivity and selectivity in the range of 0.5 to 100 ppm with an extremely low theoretical limit level of detection (80 ppb) at ambient temperature. The response and recovery time of rGO/Eu(TPyP)(Pc) hybrid aerogel based sensor to20 ppm NO2 were 172 and 828 s, respectively. Remarkably, the hydrophobic porous structure of rGO/Eu(TPyP)(Pc) hybrid aerogel endows the prepared sensor with excellent immunity to high relative humidity, which conquered the key technical issue of real application. The present sensor, simultaneously featured with high performance, low-power consumption, and good tolerance to environmental variations, is anticipated to offer the "on-site" and "on-line" measurement tool in real samples.

11.
Mikrochim Acta ; 186(8): 559, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31338594

RESUMO

An amplified electrochemical biosensing scheme is described for lead(II) ions. It is making use of DNAzyme-assisted target recycling and catalytic hairpin assembly (CHA). The hairpin strand (substrate probe for the Pb2+-based DNAzyme; referred to as SP) is composed of trigger probe (TP) and a capture probe 1 attached to gold nanoparticles (AuNP). In the presence of the enzyme probe that partially hybridizes with SP, the introduction of Pb2+ triggers target recycling and drives the highly amplified translation of target Pb(II) to TP. The CHA reaction is further initiated by TP. The modified AuNP act as the connecting unit, and this leads to the formation of a 3D DNA-AuNP network on the electrode (which is the third amplification step). It can bind the positively charged redox mediator RuHex via electrostatic interaction for electrochemical detection. This biosensor has a low detection limit (95 pM) and any analytical range that covers the 100 pM to 5 µM Pb(II) concentration range. It is selective over other divalent metal ions. It was applied to the determination of Pb2+ in spiked real-world samples. Graphical abstract Schematic presentation of the electrochemical biosensor. The triply amplified electrochemical assay is based on the use of DNAzyme-assisted target recycling with catalytic hairpin assembly (CHA) reaction for sensitive and selective determination of lead ion (Pb2+). AuNP: gold nanoparticles; SP: substrate probe; EP: enzyme probe.

12.
Analyst ; 144(16): 4795-4802, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31274133

RESUMO

A simple and robust fluorescence sensing strategy has been developed for the detection of pathogenic bacteria by the combination of the dual functionality of phi29 DNA polymerase with isothermal circular strand displacement polymerization (ICSDP). The strategy relies on target-triggered formation of a mature primer that initiates the cyclic strand displacement polymerization reaction with the aid of dual functional phi29; thus, amplified detection of the target can be achieved. To our knowledge, this work is the first report where dual functional phi29-assisted ICSDP has been employed for fluorescence sensing of pathogenic bacteria. It is worth noting that a hairpin pre-primer is introduced that can be trimmed into a mature primer for initiating ICSDP via the 3' → 5' proofreading exonuclease activity of phi29, which contributes to the ultrahigh specificity of the strategy owing to the elimination of the unwished nonspecific extension. On the basis of the present amplification strategy, our biosensor exhibits excellent specificity and sensitivity toward S. typhimurium with an excellent detection limit as low as 1.5 cfu mL-1. In addition, the strategy offers the advantages of a simplified operation, shortened analysis time, and highly sensitive detection of pathogens with only a one-step reaction. Furthermore, by redesigning the corresponding binding molecules, the proposed strategy can be easily extended for the detection of a wide spectrum of analytes. Hence, the dual functional phi29-assisted ICSDP strategy indeed creates a robust and convenient fluorescence sensing platform for the identification of pathogenic bacteria and related food safety analysis.

13.
Anal Chem ; 91(15): 10320-10327, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31267731

RESUMO

Interventional medical detection techniques require expensive devices and cause inconvenience and discomfort to the human body, which restricts their application to the frequency and duration of measurements. A noninvasive respiration test is urgently required for the next-generation medical technologies in early disease warning and postoperative monitoring. This article describes a noninvasive and wearable sensing device that shows high sensitivity toward acetone in respiratory gases with excellent stability, low energy consumption, and reliable flexibility. To obtain such a sensor, the organic semiconductor compound La(TBPP)(TBNc) (TBPP = tetrakis(4-tert-butylphenyl)porphyrin; TBNc = tetrakis(4-tert-butylphenyl)naphthalocyanine) was synthesized and further self-assembled into a highly ordered flexible film via a simple solution-vapor annealing method. The fabricated flexible film was deposited on an interdigitated electrode with poly(ethylene terephthalate) substrate and employed as an electrical identification component for a respiration sensor. Thanks to the attractive electron-transfer properties of highly ordered films and strong electron affinity of La(TBPP)(TBNc) molecules, the as-prepared sensor shows a low detection limit (200 ppb) and acceptable selectivity. The wrinkled/rippled structure of films endows the fabricated sensors with the ability of mechanical flexibility. More importantly, the experimental results suggest the potential application of acetone identification in real respiratory gases and provide a new concept for the development of noninvasive and wearable medical diagnostic devices.

14.
Analyst ; 144(17): 5245-5253, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31361292

RESUMO

We have formulated a rapid and high-efficiency fluorescent biosensing platform based on a target-activated triple-helix molecular switch (THMS)-conformation-change-induced exponential rolling circular amplification (RCA) strategy for the ultrasensitive detection of miR-21. In this strategy, there are several aspects that are worthwhile. First, the functionalized THMS, comprising a typical triplex structure (T-A·T), specific recognition sequence for nicking endonuclease, complementary sequence for miR-21, and RCA product-annealing sequence, was concurrently used to perform signal transduction with one fluorophore and one quencher. As compared to the traditional double-helix molecular switches or molecular beacons, one of the biggest differentiating factors is that the properties of THMSs are independent of any specific binding sequence that they may contain. As far as we know, this is the first time that an ingeniously designed THMS not only contains the primer for exponential RCA, but also functions as the tracer for fluorescence assay. In the presence of miR-21, targets can induce conformation changes in THMS with the release of the trapped DNA segment (P), which, in turn, can activate the first run of the RCA process. Meanwhile, the RCA reaction is also initiated by the formation of a similar primer (SP) as the trapped DNA through a continuous "extension-nicking" reaction. Secondly, the resultant first-generation RCA product consists of numerous tandem repeated regions that can attach to countless THMSs, resulting in the release of the trapped DNA segment (P) for initiating the second run of the RCA reaction. Significantly, a large amount of THMSs were continuously consumed to yield a remarkably strong fluorescent signal. In addition, this biosensor was demonstrated to exhibit improved sensitivity owing to the high efficiency and rapid amplification kinetics of the exponential RCA and high selectivity toward miR-21 with a limit of detection as low as 1.1 aM. Hence, the target-mediated THMS-conformation-change-initiated exponential RCA strategy presents an optimal detection performance toward analytes for potential applications in related fundamental research and clinical diagnosis.

15.
Anal Chem ; 91(15): 10273-10281, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31287288

RESUMO

In this work, a triggerable H2O2-cleavable fluid switch mediated paper-based biochip, being amenable to multiplexing and quantitative analysis with the dual-response output of visual screening and ratiometric electrochemistry, was developed for sensitive detection of target on-site. By properly implanting hydrophobic Ag-H2O2 responsive material in specific zone to form a programmable fluid switch, the biochip could achieve different modes of blocking/connecting switching automatically. In order to improve the test performance, a ratiometric electrochemical signal readout was designed, which was enhanced by a secondary in situ growth method fabricating trepang-shaped Au modified paper working electrode. In virtue of hybridization chain reaction, classic competitive recognition interactions of aptamer and target, and ratiometric internally calibrated mechanisms, ultrasensitive detection of the target was realized. To acquire a more quantitative and straightforward naked eye visual screening, the hydrophobic Ag switch was triggered by stimulating instructions from H2O2, thus reconnecting the electrochemical and ratiometric units automatically and resulting in a "signal on" visual fluidic flow on the chemometer characterized by the accurate distance of color development as a detection motif. With MCF-7 and K562 cells as models, wider linear detection ranges from 150 to 1.0 × 107 and 220 to 7.0 × 106 cells mL-1 for MCF-7 and K562 cells, respectively, were achieved. Meanwhile, thanks to the paper fluid chemometer, an acceptable screening detection limit of 103 cells mL-1 was obtained in the quantitative colorimetric assays. The proposed paper-based biochips opened up new horizons for designing of integratable, easy-to-use, and precise point-of-care testing devices.

16.
Analyst ; 144(16): 4995-5002, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31328736

RESUMO

Herein, a split G-quadruplex DNAzyme as a signal reporter was integrated into an electrochemical sensing platform for the detection of antibiotics with specificity and sensitivity. To improve the signal-to-noise ratio, two G-rich oligonucleotide sequences (G1 and G2) were blocked into two different hairpin probes, preventing the two segments from assembling into a spilt G-quadruplex structure. Moreover, we designed a double-arch probe, consisting of an aptamer as the recognition element and two-step enzymatic signal amplification. Concretely, the first is the Nt.BbvCI-assisted nicking cyclic reaction activated by target-aptamer binding, and the second is exonuclease III-aided cyclic amplification for generating abundant G1 and G2. The modified capture probe on the electrode was used to combine G1 and G2 to form the spilt G-quadruplex/hemin when K+ and hemin were present. This complex plays the role of DNAzyme with superior horseradish peroxidase activity in catalyzing the decomposition of H2O2. Under optimal conditions, this biosensor showed an excellent performance for sensing kanamycin with a detection limit of 83 fM for kanamycin concentrations ranging from 100 fM to 1 nM. Hence, the proposed strategy has potential as an efficient and actual platform for small molecule analysis.

17.
Medicine (Baltimore) ; 98(28): e16297, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31305414

RESUMO

AIM: Accumulating evidence has explored the effect of mesalazine on irritable bowel syndrome (IBS). However, these studies remain inconsistent. Thus, a meta-analysis was conducted to estimate the role of mesalazine on IBS. METHODS: PubMed, Medline, Embase, Web of Science, and the Cochrane Library Database were searched for all relevant randomized, controlled, blinded trials on mesalazine in patients with IBS between January 1980 and October 2018. All statistical analyses were performed using Revman 5.3 software. A fixed-effects model was adopted, 95% confidence intervals for SMD was calculated. Heterogeneity was evaluated by χ test and I statistic. RESULTS: Five studies involving 387 participants were finally included in this meta-analysis. The results showed that the SMD for clinical efficacy on abdominal pain in IBS patients treated with mesalazine in comparison to placebo was 0.19 (95% CI = -0.01 to 0.39, P = .06), which was statistically non-significant but clinically important. For beneficial effect of abdominal bloating, the SMD was 0.05 (95% CI = -0.20 to 0.30, P = .70), which was statistically non-significant. In regard to clinical efficacy on defecation frequency per day, the results revealed that the SMD was 0.29 (95% CI = -0.14 to 0.73, P = .18), which was statistically non-significant but clinically important. As for beneficial effect of general well-being, we found that the SMD was 0.41 (95% CI = -0.75 to 1.58, P = .49), which was statistically non-significant. With respect to stool consistency, the SMD was 0.01 (95% CI = -0.31 to 0.33, P = .96), which was statistically non-significant. For the effect of defecation urgency severity in IBS patients treated with mesalazine in comparison to placebo, we detected a surprising result with an SMD of 0.54 (95% CI = 0.05-1.04, P = .03), which was statistically significant. There was no significant difference between mesalazine group and placebo group on total mucosal immune cell counts of the patients with IBS with an SMD of -1.64 (95% CI = -6.17 to 2.89, P = .48) and there was also no significant difference in adverse reactions between two groups with an SMD of 1.05 (95% CI = 0.76-1.46 P = .77). CONCLUSION: Mesalazine is not superior to placebo in relieving clinical symptoms of abdominal pain, abdominal bloating, and general well-being of IBS and has no advantage of reducing defecation frequency per day and immune cell infiltration and improving stool consistency though without adverse reactions of mesalazine compared with placebo. For defecation urgency severity, placebo is even superior to mesalazine for IBS patients. Thus, mesalazine might be a cost burden to patients without providing good effectiveness. In view of the small sample size of the current study and the differences in every experimental designs, this study has high heterogeneity and requires subsequent verification.


Assuntos
Fármacos Gastrointestinais/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Mesalamina/uso terapêutico , Humanos , Falha de Tratamento
18.
ACS Sens ; 4(8): 2140-2149, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31353891

RESUMO

Multiplexed detection of Alzheimer's disease (AD) core biomarkers is of great significance to early diagnosis and personalized treatment of AD patients. Herein, we construct a robust and convenient surface-enhanced Raman scattering (SERS) biosensing platform for simultaneous detection of Aß(1-42) oligomers and Tau protein using different Raman dye-coded polyA aptamer-AuNPs (PAapt-AuNPs) conjugates. This strategy relies on the specific protein-aptamer binding-mediated aggregation of AuNPs and the concomitant plasmonic coupling effect that allow us to "turn on" SERS detection of protein biomarkers. To the best of our knowledge, this is the first work in which PAapt-AuNPs conjugates are used for probing protein biomarkers, which may be enlightening for the exploitation of more extensive biological applications of aptamer-AuNPs conjugates. The results reveal that the present strategy displays excellent analytical performance. Moreover, the applicability of this strategy is demonstrated in the artificial cerebrospinal fluid (CSF) samples with satisfactory results. Except for the prominent sensitivity and practicality, our strategy offers additional advantages. The preparation of nanoconjugates is handy and easily repeated, and the synthesis cost is greatly reduced because it dispenses with the complicated labeling process. Moreover, the assay can be accomplished in 15 min, allowing rapid detection of protein biomarkers. Furthermore, simultaneous detection of Tau protein and Aß(1-42) oligomers is realized by employing different Raman dye-coded nanoconjugates, which is valuable for accurately predicting and diagnosing AD disease. Thus, our PAapt-AuNPs conjugate-based multiplexed SERS strategy indeed creates a useful and universal platform for detecting multiple protein biomarkers and related clinical diagnosis.

19.
J Nanosci Nanotechnol ; 19(12): 7871-7878, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31196302

RESUMO

Graphene/CdS composites were synthesized through the direct deposition of CdS nanoparticles on graphene sheets. The high conductivity of graphene sheets and the intimate heterointerfacial connection between graphene sheets and CdS nanoparticles provided prominent advantages for enhancing light absorption and facilitating the transfer of photogenerated carriers from CdS nanoparticles, thus leading to an effectively separation of electron-hole pairs and consequently an improvement in photocurrent intensity. A highly sensitive and selective photoelectrochemical sensor for detecting copper ions (Cu2+) was developed based on the interaction between Cu2+ and CdS by forming CuxS-coated CdS nanoparticles, which serves as the recombination centers, impedes the transfer of electron from the conduction band of CdS to graphene sheets, and consequently leads to a decrease in photocurrent intensity. The sheets not only effectively transferred the photogenerated electrons deriving from CdS nanoparticles but also resulted in an enhancement in photocurrent intensity in the presence of various metal ions except Cu2+. The sheets amplified the photoelectric response of CdS semiconductor for Cu2+ sensing, in which the photocurrent intensity decreased dramatically.

20.
J Sci Food Agric ; 99(12): 5586-5593, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31152446

RESUMO

BACKGROUND: Mono-, di- and oligosaccharides, polyhydric alcohols and lipids are three main types of plasticizers used to process food materials. In the present study, inulin, maltitol and lecithin were selected as representative oligosaccharide, polyhydric alcohol and lipid fat replacers, respectively. Their effects on the physicochemical properties of reduced-fat mozzarella cheese were evaluated. RESULTS: Lecithin reduced the hardness and increased the degree of free oil released. Inulin and lecithin decreased the hydrophobic interaction of reduced-fat cheese. Maltitol improved the elasticity of the reduced-fat cheese and increased the hydrophobic interaction within the casein matrix. Maltitol-added cheese had a lower glass transition temperature (Tg ) than the other cheeses. Maltitol significantly improved the stretchability of the reduced-fat cheese. CONCLUSION: The results obtained in the present study suggest that maltitol is an effective fat replacer in reduced-fat mozzarella cheese and might enhance the cheese's functional properties. The Tg of cheese was related to the water and fat content, fat replacer addition and cross-linking degree of casein. The relationship between Tg and the physicochemical properties of cheese will be studied in further research. © 2019 Society of Chemical Industry.


Assuntos
Queijo/análise , Substitutos da Gordura/análise , Aditivos Alimentares/análise , Inulina/análise , Lecitinas/análise , Maltose/análogos & derivados , Plastificantes/análise , Álcoois Açúcares/análise , Animais , Caseínas/análise , Bovinos , Manipulação de Alimentos , Dureza , Maltose/análise
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