Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 26
Filter
1.
J Org Chem ; 89(11): 7859-7864, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38773955

ABSTRACT

Regioselective methods to access alkylated tetrazoles still remain a challenging goal. Herein, we describe a novel regioselective protocol for N2-arylation of tetrazoles with diazo compounds using inexpensive Al(OTf)3. This reaction could be conducted under mild conditions to access a diverse array of alkylated tetrazoles with 2-substituted tetrazoles as the major products, demonstrating a comprehensive range of substrate compatibility and excellent functional group compatibility. Mechanistic studies revealed a carbene-free process in this reaction procedure. Furthermore, the scale-up reaction and transformations of the N2-arylation of tetrazole products demonstrated the potential of this strategy.

2.
Small ; 20(9): e2304941, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37822184

ABSTRACT

Urolithiasis stands as a prevalent ailment within the urinary system, with hyperoxaluria and hypocitraturia being the most frequent manifestations characterized by excessive oxalic acid (OA) and deficient citric acid (CA) levels in urine. Detecting these compounds in urine quantitatively holds paramount importance for early urolithiasis screening. Existing methodologies fall short in achieving simultaneous and on-site identification of OA and CA, posing challenges for accurate urolithiasis screening. Addressing this concern, the study successfully accomplishes the concurrent identification of OA and CA in urine through a combination of dual-spectral analysis and biomimetic peroxidase utilization. Bovine serum albumin and dithiothreitol-modified copper nanoclusters (BSA-DTT-CuNCs) are employed as biomimetic peroxidases, effectively mitigating interference and enabling the simultaneous determination of OA and CA. The quantification range spans from 0 to 12 mm for OA and 0.5 to 2.5 mm for CA, with detection limits of 0.18 and 0.11 mm, respectively. To facilitate swift and on-location urine analysis, a fully automated urine analyzer (FAUA) is introduced that streamlines the process of biomarker pretreatment and identification within urine samples. Validation with real urine samples from urolithiasis patients demonstrates the method's diagnostic precision, highlighting the dual-spectral technique and analyzer's promising role in urolithiasis screening.


Subject(s)
Peroxidase , Urolithiasis , Humans , Oxalic Acid , Biomimetics , Peroxidases , Urolithiasis/diagnosis , Citric Acid , Coloring Agents
3.
Nature ; 621(7980): 840-848, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37674084

ABSTRACT

In both cancer and infections, diseased cells are presented to human Vγ9Vδ2 T cells through an 'inside out' signalling process whereby structurally diverse phosphoantigen (pAg) molecules are sensed by the intracellular domain of butyrophilin BTN3A11-4. Here we show how-in both humans and alpaca-multiple pAgs function as 'molecular glues' to promote heteromeric association between the intracellular domains of BTN3A1 and the structurally similar butyrophilin BTN2A1. X-ray crystallography studies visualized that engagement of BTN3A1 with pAgs forms a composite interface for direct binding to BTN2A1, with various pAg molecules each positioned at the centre of the interface and gluing the butyrophilins with distinct affinities. Our structural insights guided mutagenesis experiments that led to disruption of the intracellular BTN3A1-BTN2A1 association, abolishing pAg-mediated Vγ9Vδ2 T cell activation. Analyses using structure-based molecular-dynamics simulations, 19F-NMR investigations, chimeric receptor engineering and direct measurement of intercellular binding force revealed how pAg-mediated BTN2A1 association drives BTN3A1 intracellular fluctuations outwards in a thermodynamically favourable manner, thereby enabling BTN3A1 to push off from the BTN2A1 ectodomain to initiate T cell receptor-mediated γδ T cell activation. Practically, we harnessed the molecular-glue model for immunotherapeutics design, demonstrating chemical principles for developing both small-molecule activators and inhibitors of human γδ T cell function.


Subject(s)
Butyrophilins , Lymphocyte Activation , Phosphoproteins , Receptors, Antigen, T-Cell, gamma-delta , T-Lymphocytes , Animals , Humans , Antigens, CD/immunology , Antigens, CD/metabolism , Butyrophilins/immunology , Butyrophilins/metabolism , Camelids, New World/immunology , Molecular Dynamics Simulation , Phosphoproteins/immunology , Phosphoproteins/metabolism , Receptors, Antigen, T-Cell, gamma-delta/immunology , Receptors, Antigen, T-Cell, gamma-delta/metabolism , T-Lymphocytes/cytology , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Crystallography, X-Ray , Nuclear Magnetic Resonance, Biomolecular , Thermodynamics
4.
Article in English | MEDLINE | ID: mdl-37380882

ABSTRACT

Studies of how positive and negative coping styles affect social anxiety show mixed results. Hence, our two meta-analyses determined the overall effect sizes of problem solving-focused coping (PSC) styles and emotion-focused coping (EFC) styles on social anxiety in mainland China (PSC: k = 49 studies, N = 34,669; EFC: k = 52, N = 36,531). PSC was negatively linked to social anxiety (- .198), and EFC was positively linked to social anxiety (.223). In years with more national income, PSC's and EFC's effect sizes were larger. PSC's effect sizes were smaller among rural students (vs. urban students), larger among older students (university, high school, middle school), and larger in cross-sectional (vs. longitudinal) studies. When using SAD (vs. others) social anxiety measures, PSC effect sizes were larger, but EFC effect sizes were smaller. EFC effect sizes were larger in studies with convenience (vs. representative) samples. Gender, single child status, and coping style measurement showed no moderation effects. These findings suggest that using problem solving-focused coping styles rather than emotion-focused may reduce social anxiety, so future experimental studies can test this idea more rigorously.

5.
Acta Pharm Sin B ; 2023 Apr 18.
Article in English | MEDLINE | ID: mdl-37360012

ABSTRACT

Via an insufficient coat protein complex I (COPI) retrieval signal, the majority of SARS-CoV-2 spike (S) is resident in host early secretory organelles and a tiny amount is leaked out in cell surface. Only surface-exposed S can be recognized by B cell receptor (BCR) or anti-S therapeutic monoclonal antibodies (mAbs) that is the trigger step for B cell activation after S mRNA vaccination or infected cell clearance by S mAbs. Now, a drug strategy to promote S host surface exposure is absent. Here, we first combined structural and biochemical analysis to characterize S COPI sorting signals. A potent S COPI sorting inhibitor was then invented, evidently capable of promoting S surface exposure and facilitating infected cell clearance by S antibody-dependent cellular cytotoxicity (ADCC). Importantly, with the inhibitor as a probe, we revealed Omicron BA.1 S is less cell surface exposed than prototypes because of a constellation of S folding mutations, possibly corresponding to its ER chaperone association. Our findings not only suggest COPI is a druggable target against COVID-19, but also highlight SARS-CoV-2 evolution mechanism driven by S folding and trafficking mutations.

6.
Acta Pharm Sin B ; 13(1): 246-255, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36815035

ABSTRACT

The C-glycosidic bond that connects the sugar moiety with aglycone is difficult to be broken or made due to its inert nature. The knowledge of C-glycoside breakdown and synthesis is very limited. Recently, the enzyme DgpA/B/C cascade from a human intestinal bacterium PUE was identified to specifically cleave the C-glycosidic bond of puerarin (daidzein-8-C-glucoside). Here we investigated how puerarin is recognized and oxidized by DgpA based on crystal structures of DgpA with or without substrate and biochemical characterization. More strikingly, we found that apart from being a C-glycoside cleaving enzyme, DgpA/B/C is capable of efficiently converting O- to C-glycoside showing the activity as a structure isomerase. A possible mechanistic model was proposed dependently of the simulated complex structure of DgpB/C with 3″-oxo-daidzin and structure-based mutagenesis. Our findings not only shed light on understanding the enzyme-mediated C-glycosidic bond breakage and formation, but also may help to facilitate stereospecific C-glycoside synthesis in pharmaceutical industry.

7.
Analyst ; 147(23): 5314-5323, 2022 Nov 21.
Article in English | MEDLINE | ID: mdl-36322158

ABSTRACT

PbTx-2 and okadaic acid (OA) are two typical marine toxins that are highly toxic and harmful to human health. The approach based on citrate-capped gold nanoparticles (Cit-AuNPs) and specific aptamers to construct label-free colorimetric sensors is a widely used method for marine toxin detection. However, the potential interactions between Cit-AuNPs and target molecules have always been ignored, which may result in wrong analytical results due to shortcomings in the Cit-AuNPs. To overcome these shortfalls, in this work, AuNPs were synthesized using tyrosine as a reducing and capping agent, and a robust colorimetric aptasensor based on tyrosine-capped AuNPs (Tyr-AuNPs) was constructed for the label-free detection of marine toxins. Tyr-AuNPs presented better stability compared to Cit-AuNPs due to the stronger binding of amine groups on tyrosine to AuNPs through the Au-N bond. Interactions between Tyr-AuNPs and PbTx-2 were analyzed through UV-vis and isothermal titration calorimetry methods and the results validated the robustness of the Tyr-AuNPs. Colorimetric aptasensors were established for PbTx-2 and OA detection with a linear range of 0.05-4 ppm and limits of detection of 2.25 ppb and 5.19 ppb, respectively. These results demonstrate that the developed colorimetric aptasensor can be a robust and promising method for marine toxin detection.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Metal Nanoparticles , Humans , Gold/chemistry , Colorimetry/methods , Metal Nanoparticles/chemistry , Tyrosine , Okadaic Acid , Aptamers, Nucleotide/chemistry , Limit of Detection , Biosensing Techniques/methods
8.
Carbohydr Polym ; 296: 119970, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36088009

ABSTRACT

The design-on-demand of lignocellulose nanofibril-based materials for contaminant disposal is worth exploring. Herein, we mildly extract sulfated lignocellulose nanofibrils from bagasse via a deep eutectic solvent-based approach, and use them as a matrix for TiO2 nanoparticles (TNPs) towards adsorption-photocatalytic synergistic removal of tetracycline (TC). The resultant lignocellulose-based nanocomposite aerogel possessing a high specific surface area (95.3 m2/g), surface charge density (1.78 mmol/g) and well-preserved lignocellulosic structure, strongly adsorbed TC with a maximum adsorption capacity of 70 mg/g via a combination of intermolecular interactions (i.e., hydrogen bonding and π-π stacking) and electrostatic forces. Furthermore, the excellent photocatalytic activity of uniformly distributed TNPs in combination with the outstanding adsorption capacity of nanocomposite aerogel can synergistically remove TC in a dynamic and continuous process, during which ~90 % TC (10 mg/L) was efficiently removed within 40 min. HPLC-MS was performed to reveal the degradation pathways of TC. Meanwhile, our developed nanocomposite aerogel demonstrated favorable structural stability and recyclability, which together supported its durability for environmental remediation.


Subject(s)
Heterocyclic Compounds , Water Pollutants, Chemical , Adsorption , Anti-Bacterial Agents/chemistry , Lignin , Sulfates , Sulfur Oxides , Tetracycline/chemistry , Water Pollutants, Chemical/chemistry
9.
Front Psychol ; 13: 892884, 2022.
Article in English | MEDLINE | ID: mdl-36017436

ABSTRACT

This study applied cognitive diagnostic models to assess students' learning progressions in energy. A Q-matrix (i.e., an item attribute alignment table) was proposed based on existing literature about learning progressions of energy in the physical science domain and the Trends in International Mathematics and Science Study (TIMSS) assessment framework. The Q-matrix was validated by expert review and real data analysis. Then, the deterministic inputs, noisy 'and' gate (DINA) model with hierarchical relations was applied to data from three jurisdictions that had stable, defined science curricula (i.e., Australia, Hong Kong, and Ontario). The results suggested that the hypothesized learning progression was consistent with the observed progression in understanding the energy concept. We also found similarities in students' attribute mastery across the three jurisdictions. In addition, we examined the instructional sensitivity of the selected item. We discuss several curriculum-related issues and student misconceptions that may affect students' learning progressions and mastery patterns in different regions of the world.

10.
Article in English | MEDLINE | ID: mdl-35842552

ABSTRACT

Previous research on the relationship between parenting style and social anxiety in Chinese youth has been inconsistent, which has made it difficult to consider whether improving parenting may serve as a preventative intervention for social anxiety. The current study aimed to clarify these inconsistencies by examining the strength of the association between positive/negative parenting style and social anxiety among Chinese students and the role of certain moderators in those associations. A meta-analysis was conducted on 53 studies with a total sample of 26,024 Chinese mainland students. Separate analyses were conducted for positive parenting style and social anxiety (N = 24,081), and negative parenting style and social anxiety (N = 24,933). Findings suggest a small negative association exists between positive parenting style and social anxiety, and a small positive association exists between negative parenting style and child social anxiety. Analyses suggested type of social anxiety measures, developmental stage, and gender all moderated the relationships between parenting style and social anxiety. Results clarify the direction of the relationship between parenting and social anxiety amongst Chinese youth and point to particular implications and future directions for policy, practice, and research.

11.
OMICS ; 26(4): 236-245, 2022 04.
Article in English | MEDLINE | ID: mdl-35230178

ABSTRACT

Malnutrition is a common complication in children with cancer. Cancer treatment and malnutrition can disrupt gut microbiome diversity and composition. The gut microbiome is of broad interest to better understand the mechanisms of malnutrition in cancer therapy. This study aimed to compare the gut microbiome between children with solid tumors postchemotherapy and healthy controls, and investigated the association of the putative microbiome differences with diet. Study participants were 27 children (7-18 years) with solid tumors within the first year after the completion of chemotherapy and 22 healthy controls. The study groups did not have a statistically significant difference in age, race, sex, and body mass index. At study intake, the participants completed the Block Kids Food Screener for dietary intakes in the past week. Fecal specimens were collected and analyzed for the gut microbiome. The cancer and control groups differed in gut microbial ß-diversity and abundance analyses. The macronutrient intakes such as carbohydrates, fiber, beta-carotene, and vitamin B6 were positively associated with α-diversity. Children with adequate vitamin B6 had a higher Chao1 diversity index than children with inadequate or excessive intake (p = 0.0004). Children with excessive selenium intake had a trend for higher Pielou's_e index than children with inadequate intake (p = 0.091). Maintaining a healthy gut microbiome is critical among children with cancer. This study provides new insights on the linkages between dietary intakes and the gut microbiome in children with solid tumors postchemotherapy. These findings, if replicated in future independent studies, may help anticipate malnutrition and plan for personalized nutrition approaches during chemotherapy in pediatric cancers.


Subject(s)
Gastrointestinal Microbiome , Malnutrition , Neoplasms , Child , Cross-Sectional Studies , Diet , Humans , Neoplasms/drug therapy , Vitamin B 6
12.
Polymers (Basel) ; 14(5)2022 Feb 24.
Article in English | MEDLINE | ID: mdl-35267733

ABSTRACT

The accumulation of dissolved and colloidal substances (DCS) in the increasingly closed paper circulating water system can seriously lower the productivity and safety of papermaking machines, and it has been a challenge to develop an adsorbent with low cost, high adsorption efficiency and large adsorption capacity for DCS removal. In this study, cationic lignocellulose nanofibers (CLCNF) were obtained by cationic modification of agricultural waste bagasse in deep eutectic solvents (DES) followed by mechanical defibrillation, and then CLCNF were employed as an adsorbent for DCS model contaminant polygalacturonic acid (PGA) removal. CLCNF was characterized by transmission electron microscopy, Fourier transform infrared, elemental analysis, X-ray diffraction, and thermogravimetric analysis. The analytical results confirmed the successful preparation of CLCNF with 4.6-7.9 nm diameters and 0.97-1.76 mmol/g quaternary ammonium groups. The effects of quaternary ammonium group contents, pH, contact time and initial concentration of PGA on the adsorption were investigated in a batch adsorption study. According to the results, the cationic modification significantly enhanced the adsorption of PGA by CLCNF and the adsorption performance increased with the increase of the quaternary ammonium group contents. The adsorption of PGA on CLCNF followed the pseudo-second-order and the fitted Langmuir isotherm model. The adsorption showed fast initial kinetics and the experimental maximum adsorption capacity was 1054 mg/g, which is much higher than PGA adsorbents previously reported in the literature. Therefore, CLCNF with high cationic group content developed in this paper is a promising adsorbent for DCS removal.

13.
Anal Chim Acta ; 1191: 339178, 2022 Jan 25.
Article in English | MEDLINE | ID: mdl-35033273

ABSTRACT

Citric acid (CA) has been considered as a biomarker of urolithiasis due to its vital suppression role in urinary stone formation. Most analytical methods for detecting CA are complicated and require expensive equipment. Herein, a colorimetric method based on sodium dodecylsulfate (SDS) modified AgNPs was presented for convenient and portable detection of CA in urine. By detecting the absorption of the solution color, the quantitative detection of CA can be achieved. The pH value of SDS-AgNPs, concentration of Al3+ and incubation time were optimized. Under optimal conditions, the method has the detection range of 1-10 mg/L, with a limit of detection (LOD) of 0.21 mg/L. Moreover, a self-developed portable CD(Compact Disk)-spectrometer (CDs) was established for detecting CA with a LOD of 0.49 mg/L featuring high simplicity, low time cost and good portability. This method was also validated with good selectivity to CA. In addition, the artificial urine samples were also detected to verify the capability of the method and CDs. The results validated that the method integrating with the CDs can be a promising platform for citric acid detection that can be further used for early screening and prognostic monitoring of urolithiasis.


Subject(s)
Metal Nanoparticles , Urolithiasis , Biomarkers , Citric Acid , Colorimetry , Humans , Silver , Sodium , Sodium Dodecyl Sulfate , Urolithiasis/diagnosis
14.
Talanta ; 239: 122903, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34857381

ABSTRACT

Heavy metal pollution has severe threats to the ecological environment and human health. Thus, it is urgent to achieve the rapid, selective, sensitive and portable detection of heavy metal ions. To overcome the defects of traditional methods such as time-consuming, low sensitivity, high cost and complicated operation, QDs (Quantum dots)-based nanomaterials have been used in sensors to significantly improve the sensing performance. Due to their excellent physicochemical properties, high specific surface area, high adsorption and reactive capacity, nanomaterials could act as potential probes or offer enhanced sensitivity and create a promising nanosensors platform. In this review, the rapidly advancing types of QDs for heavy metal ions detection are first summarized. Modified with ligands, nanomaterials, or biomaterials, QDs are assembled on sensors by the interaction of electrostatic adsorption, chemical bonding, steric hindrance, and base-pairing. The stability of QDs-based nanosensors is improved by doping the elements to QDs, providing the reference substance, optimizing the assemble strategies and so on. Then, according to transducer principles, the two most typical sensor categories based on QDs: optical and electrochemical sensors are highlighted to be discussed. In the meanwhile, portable devices combining with QDs to adapt the practical detection in complex situations are summarized. The deficiencies and future challenges of QDs in toxicity, specificity, portability, multi-metal co-detection and degradation during the detection are also pointed out. In the end, the development trends of QDs-based nanosensors for heavy metal ions detection are discussed. This review presents an overall understanding, recent advances, current challenges and future outlook of QDs-based nanosensors for heavy metal detection.


Subject(s)
Metals, Heavy , Nanostructures , Quantum Dots , Humans , Ions , Transducers
15.
Anal Methods ; 13(38): 4345-4353, 2021 10 08.
Article in English | MEDLINE | ID: mdl-34622887

ABSTRACT

Okadaic acid (OA) is one of the marine toxins that are widely distributed and harmful to humans. However, the current detection methods for OA involve complex procedures, need long detection time, and rely on large-scale laboratory equipment. In this work, a multi-channel handheld automatic spectrometer (MHAS) based on a spectral sensor was developed with the advantages of small size, simple operation and low cost. It could achieve rapid detection within 30 s and a wide spectral detection range of 470-780 nm with a broadband LED as the light source and a microplate containing 8 wells as a sample cell. Moreover, through the combination of gold nanoparticles (AuNPs) and aptamer-OA34, a highly sensitive and rapid system for OA detection was established with a LOD of 1.80 µg L-1 and a wide detection range of 20-10 000 µg L-1, which is comparable to a microplate reader. Compared with other studies, the proposed MHAS realized rapid on-site detection of OA with a wider detection range, shorter detection time and higher portability. Therefore, the MHAS promises to be a stable and efficient optical detection instrument for on-site detection in the fields of food safety, disease diagnosis and environmental monitoring.


Subject(s)
Gold , Metal Nanoparticles , Humans , Marine Toxins , Okadaic Acid , Refractometry
16.
Anal Chim Acta ; 1179: 338603, 2021 Sep 22.
Article in English | MEDLINE | ID: mdl-34535249

ABSTRACT

Light-addressable potentiometric sensor (LAPS) has been widely used in biomedical applications since its advent. As a member of the potentiometric sensors, ion-sensitive LAPS (ISLAPS) can be obtained by modifying ion selective sensing membrane on the sensor surface. Compared with the conventional ion-selective electrodes (ISEs) with liquid contact, the all-solid-state ISEs have more advantages such as easy maintenance, more convenient for miniaturization and practical applications. However, the commonly used ion-sensitive membrane (ISM) matrix like PVC has many limitations such as poor adhesion to silicone-based sensor and easy overflow of the plasticizer from the membrane. In this work, LAPS was combined with a variety of ionophore-doped all-solid-state silicone-rubber ISMs for the first time, to establish a program-controlled multiplexed ISLAPS system for physiological ions (Na+, K+, Ca2+ and H+) detection. The silicone-rubber ISMs have better adhesion to silicon-based sensors without containing plasticizers, which can avoid the plasticizer pollution and improve the long-term stability. A layer of poly(3-octylthiophene-2,5-diyl) (P3OT) was pre-modified on the sensor surface to inhibit the formation of an aqueous layer and improve the sensor lifetime. With the aid of a translation stage, the light spot automatically illuminated the detection sites in sequence, and the response of the four ions could be obtained in one measurement within 1 min. The proposed multiplexed ISLAPS has good sensitivity with micromolar limit of detection (LOD), good selectivity and long-term stability (more than 3 months). The results of the real Dulbecco's Modified Eagle Medium (DMEM) sample detection proved that the ISLAPS system can be used for the physiological ions detection, and is promising to realize a multi-parameter microphysiometer.


Subject(s)
Rubber , Silicone Elastomers , Ion-Selective Electrodes , Ions , Potentiometry
17.
Anal Chim Acta ; 1131: 126-135, 2020 Sep 22.
Article in English | MEDLINE | ID: mdl-32928473

ABSTRACT

Cadmium ions (Cd2+) greatly threat human health and the environment due to its extremely severe toxicity. Therefore, it is of paramount importance to establish a sensitive and portable platform for monitoring Cd2+ on site. In this work, a novel microfluidic-based fluorescent electronic eye (E-eye) combined with tetrasodium iminodisuccinate (IDS)-etched CdTe/CdS quantum dots (QDs) was developed for portable and sensitive detection of trace Cd2+ in water environment. The fluorescent E-eye consists of a microfluidic chip for miniaturized flow analysis, an ultraviolet light excitation module for fluorescent excitation, an optical lens for device miniaturization and a smartphone for portable photographing and analysis. The IDS was added in the CdTe/CdS QDs to cause fluorescence quenching due to the chemical etching. Subsequently added Cd2+ will be recognized by etched QDs, thus inducing the fluorescence changes that can be directly captured by the E-eye for quantitative detection of Cd2+. With the optimization of all parameters including pH, reaction time and the concentration of IDS, the proposed platform could detect Cd2+ with a low detection limit of 0.26 µg/L in the range of 1-250 µg/L. It is worth noting that the performance of the developed fluorescent E-eye is quite comparable to a commercial microplate reader with a detailed comparison in linearity, sensitivity and detection limit. In summary, the proposed microfluidic-based fluorescent E-eye provides a promising platform for portable and high sensitive detection of trace cadmium in water environment.

18.
Anal Chim Acta ; 1120: 43-49, 2020 Jul 11.
Article in English | MEDLINE | ID: mdl-32475390

ABSTRACT

Adenosine has received great attentions acting as a potential biomarker for monitoring lung cancer. Most of the reported studies for adenosine detection require large instruments and complicated procedures. Herein, a sensitive, rapid and in-situ colorimetric aptasensor was developed for adenosine detection. Moreover, a homemade biomimetic electronic-eye (E-eye) was established and utilized as a portable in-time detection equipment. The entire measurement can be completed within 20 min, including the combination of aptamer with adenosine or AuNPs and the detection of adenosine. Four different kinds of aptamer were compared and the results showed that the AuNPs-aptamer-biotin system was the most stable and with the widest detection range of 5.0 µM-60.0 µM and the lowest LOD of 0.17 µM. Moreover, the artificial urine samples were also tested with a linear range from 5.0 to 50.0 µM and a LOD of 0.48 µM. The results validated that the aptasensor together with the E-eye can be a promising platform for adenosine detection.


Subject(s)
Adenosine/analysis , Aptamers, Nucleotide/chemistry , Biosensing Techniques , Gold/chemistry , Metal Nanoparticles/chemistry , Humans
19.
J Cell Biochem ; 121(2): 1842-1854, 2020 02.
Article in English | MEDLINE | ID: mdl-31633246

ABSTRACT

Gastric cancer (GC) is one of the most fatal common cancers in worldwide. Helicobacter pylori (H. pylori) infection is closely related to the development of GC, although the mechanism is still unclear. In our study, we aim to develop a robust messenger RNA (mRNA) signature associated with H. pylori (-) GC that can sensitively and efficiently predict the prognostic. The RNA-seq expression profile and corresponding clinical data of 598 gastric cancer samples and 63 normal samples obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus database. Using gene set enrichment analysis H. pylori (+) GC and H. pylori (-) GC patients and normal samples to select certain genes for further analysis. Using univariate and multivariate Cox regression model to establish a gene signature for predicting the overall survival (OS). Finally, we identified G2/M related seven-mRNA signature (TGFB1, EGF, MKI67, ILF3, INCENP, TNPO2, and CHAF1A) closely related to the prognosis of patients with H. pylori (-) GC. The seven-mRNA signature was identified to act as an independent prognostic biomarker by stratified analysis and multivariate Cox regression analysis. It was also validated on two test groups from TCGA and GSE15460 and shown that patients with high-risk scores based on the expression of the seven mRNAs had significantly shorter survival times compared to patients with low-risk scores (P < .0001). In this study, we developed a seven-mRNA signature related to G2/M checkpoint from H. pylori (-) GCs that as an independent biomarker potentially with a good performance in predicting OS and might be valuable for the clinical management for patients with GC.


Subject(s)
Biomarkers, Tumor/genetics , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , Helicobacter Infections/complications , Helicobacter pylori/isolation & purification , Host-Pathogen Interactions/genetics , Stomach Neoplasms/pathology , Female , Gene Expression Profiling , Helicobacter Infections/virology , Humans , Male , RNA, Neoplasm/analysis , RNA, Neoplasm/genetics , Stomach Neoplasms/genetics , Stomach Neoplasms/virology
20.
Sensors (Basel) ; 19(19)2019 Oct 03.
Article in English | MEDLINE | ID: mdl-31623395

ABSTRACT

A light-addressable potentiometric sensor (LAPS) is a semiconductor electrochemical sensor based on the field-effect which detects the variation of the Nernst potential on the sensor surface, and the measurement area is defined by illumination. Thanks to its light-addressability feature, an LAPS-based chemical imaging sensor system can be developed, which can visualize the two-dimensional distribution of chemical species on the sensor surface. This sensor system has been used for the analysis of reactions and diffusions in various biochemical samples. In this review, the LAPS system set-up, including the sensor construction, sensing and substrate materials, modulated light and various measurement modes of the sensor systems are described. The recently developed technologies and the affecting factors, especially regarding the spatial resolution and temporal resolution are discussed and summarized, and the advantages and limitations of these technologies are illustrated. Finally, the further applications of LAPS-based chemical imaging sensors are discussed, where the combination with microfluidic devices is promising.

SELECTION OF CITATIONS
SEARCH DETAIL
...