ABSTRACT
Self-regulated learning (SRL) is the ability to regulate cognitive, metacognitive, motivational, and emotional states while learning and is posited to be a strong predictor of academic success. It is therefore important to provide learners with effective instructions to promote more meaningful and effective SRL processes. One way to implement SRL instructions is through providing real-time SRL scaffolding while learners engage with a task. However, previous studies have tended to focus on fixed scaffolding rather than adaptive scaffolding that is tailored to student actions. Studies that have investigated adaptive scaffolding have not adequately distinguished between the effects of adaptive and fixed scaffolding compared to a control condition. Moreover, previous studies have tended to investigate the effects of scaffolding at the task level rather than shorter time segments-obscuring the impact of individual scaffolds on SRL processes. To address these gaps, we (a) collected trace data about student activities while working on a multi-source writing task and (b) analyzed these data using a cutting-edge learning analytic technique- ordered network analysis (ONA)-to model, visualize, and explain how learners' SRL processes changed in relation to the scaffolds. At the task level, our results suggest that learners who received adaptive scaffolding have significantly different patterns of SRL processes compared to the fixed scaffolding and control conditions. While not significantly different, our results at the task segment level suggest that adaptive scaffolding is associated with earlier engagement in SRL processes. At both the task level and task segment level, those who received adaptive scaffolding, compared to the other conditions, exhibited more task-guided learning processes such as referring to task instructions and rubrics in relation to their reading and writing. This study not only deepens our understanding of the effects of scaffolding at different levels of analysis but also demonstrates the use of a contemporary learning analytic technique for evaluating the effects of different kinds of scaffolding on learners' SRL processes.
ABSTRACT
Multiplexed microRNA (miRNA) profiling of more than four types in living cells is challenging due to fluorescent spectral overlap, representing a significant limitation in studying the complex interactions related to the occurrence and development of diseases. Herein, we report a multiplexed fluorescent imaging strategy based on an orthometric multicolor encoded hybridization chain reaction amplifier named multi-HCR. The targeting miRNA can trigger this multi-HCR strategy due to the specific sequence recognition, and then its self-assembly to amplify the programmability signals. We take the four-colored chain amplifiers, showing that the multi-HCR can form 15 combinations simultaneously. In a living process of hypoxia-induced apoptosis and autophagy under complicated mitochondria and endoplasmic reticulum stress, the multi-HCR demonstrates excellent performance in detecting eight different miRNA changes. The multi-HCR provides a robust strategy for simultaneously profiling multiplexed miRNA biomarkers in studying complicated cellular processes.
ABSTRACT
Rapid, simple, sensitive and reliable approaches for biogenic amines quantification in various food samples are essential to food safety. Lateral flow immunoassay (LFIA) has been wildly utilized in point-of-care testing (POCT) owing to its advantage of flexibility and feasibility. Here, we reported a Fe3O4@Au nanoparticles (NPs) (Fe3O4@AuNPs) based multimodal readout LFIA for rapid putrescine (Put) and histamine (His) quantification with a LOD down to 10 and 10 ng/mL in naked eye mode, 2.31 and 4.39 ng/mL in photothermal mode, 0.17 and 0.31 ng/mL in magnetic mode, respectively. Such multi-mode assay has been successfully used to detect Biogenic amines (BAs) in raw aquatic foods, including fish, prawns, beef, and pork, with overall recoveries ranging from 93.68 to 109.34%. Meanwhile, it is easily expanded to detect other typical BAs with high sensitivity by simply replacing antibodies. In view of the multi-signal reading, two quantitative formats, and high sensitivity, it may greatly widen the application of lateral flow detection in food safety.
Subject(s)
Metal Nanoparticles , Animals , Cattle , Gold , Colorimetry , Immunoassay , Putrescine , Magnetic Phenomena , Limit of Detection , Biogenic AminesABSTRACT
Author: Please verify that the changes made to improve the English still retain your original meaning.Detection of microRNA (miRNA) in dermal interstitial fluid (ISF) has emerged as clinically useful in health status monitoring. However, it remains a great challenge owing to the difficult sampling and low abundance. Here, we report a DNA hydrogel microneedles (MNs) array to realize rapid enrichment and sensitive detection of miRNA in ISF. The MNs' patch consists of methacrylate hyaluronic acid (MeHA) equipped with a smart DNA circuit hydrogels' system (MeHA/DNA), in which an appropriate miRNA input enables triggering a cascading toehold-mediated DNA displacement reaction to catalytically cleave cross-linking points to generate amplified fluorescence (FL) for miRNA detection. The MeHA/DNA-MNs patch with high mechanical strength can extract adequate ISF in a short time (0.97 ± 0.2 mg in 5 min) in vivo because of its supreme water affinity. Additionally, the cascading toehold-mediated DNA displacement signal amplification reaction allows for sensitive detection of the low-abundant miRNAs down to 241.56 pM. The DNA hydrogels' MNs present potential for minimally invasive personalized diagnosis and real-time health monitoring in clinical applications.
Subject(s)
Extracellular Fluid , MicroRNAs , Hydrogels , MicroRNAs/genetics , Needles , DNA/geneticsABSTRACT
MicroRNAs (miRNAs) are a class of small, single-stranded, and non-coding RNA molecules that act as post-transcriptional regulators of gene expression, participating in the regulation of a variety of important biological activities. Accumulating evidence suggests that miRNAs are closely related to many major human diseases, especially cancer, and they are considered to be highly promising diagnostic biomarkers and therapeutic targets for disease diagnosis and treatment. To this end, the development of highly accurate, selective, and sensitive strategies for miRNA detection is essential for realizing the early diagnosis of diseases and improving the success rate of treatment. Over the past decade, functional nucleic acid nanostructures have emerged as powerful tools for detecting disease-related miRNAs because of their unique advantages, e.g., high stability, specificity, and activity. Particularly, thanks to the rapid advancement of systematic evolution of ligands by exponential enrichment (SELEX) technology, it is now feasible to strictly select and reasonably design functional nucleic acids with high specificity and activity toward targets of interest, and thereby enhance the performance of miRNA detection. In this article, we present a comprehensive review of the application of functional nucleic acids including RNA aptamers and DNAzymes selected by SELEX in the construction of biosensors for miRNA detection in recent years. We also provide insights into the impact of the advantages of RNA aptamers and DNAzymes on the enhancement of the performance of miRNA biosensors. We hope this review will serve as a valuable foundation to inspire more exciting research in this emerging field in near future.
Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , DNA, Catalytic , MicroRNAs , Aptamers, Nucleotide/chemistry , Humans , Ligands , MicroRNAs/genetics , SELEX Aptamer TechniqueABSTRACT
The slow mass transport of the target molecule essentially limits the biosensing performance. Here, we report a Janus mesoporous microsphere/Pt-based (meso-MS/Pt) nanostructure with greatly enhanced target transport and accelerated recognition process for microRNA (miRNA) amplified detection in complex biological samples. The mesoporous MS was synthesized via double emulsion interfacial polymerization, and Pt nanoparticles (PtNPs) were deposited on the half-MS surface to construct Janus meso-MS/Pt micromotor. The heterogeneous meso-MS/Pt with a large surface available was attached to an entropy-driven DNA recognition system, termed meso-MS/Pt/DNA, and the tremendous pores network was beneficial to enhanced receptor-target interaction. It enabled moving around complex biological samples to greatly enhance target miRNA mass transport and accelerate recognition procedure due to the self-diffusiophoretic propulsion. Coupling with the entropy-driven signal amplification, extremely sensitive miRNA detection in Dulbecco's modified Eagle medium (DMEM), and cell lysate without preparatory and washing steps was realized. Given the free preparatory and washing steps, fast mass transport, and amplified capability, the meso-MS/Pt/DNA micromotor provides a promising method for miRNAs analysis in real biological samples.
Subject(s)
Biosensing Techniques , MicroRNAs , Nanoparticles , MicroRNAs/genetics , Nanoparticles/chemistry , DNA , Microspheres , Biosensing Techniques/methodsABSTRACT
Skin interstitial fluid (ISF) is a biofluid with information-rich biomarkers for disease diagnosis and prognosis. Microneedle (MN) integration of sampling and instant biomarker readout hold great potential in health status monitoring and point-of-care testing (POCT). The present work describes an attractive MN sensor array for minimally invasive monitoring of ISF microRNA (miRNA) and Cu2+. The MN array is made of methacrylated gelatin (GelMA) and methacrylated hyaluronic acid (MeHA), and a further divisionally encapsulated miRNA and Cu2+ detection system, and is cross-linked through blue-light irradiation. The MN patch displays good mechanical properties that enable withstanding more than 0.4 N per needle, and exhibits a high swelling ratio of 700% that facilitates timely extraction of sufficient ISF for biomarker analysis. For proof-of-concept, it realizes detection of miRNAs and Cu2+ efficiently and quantitatively in an agarose skin and fresh porcine cadaver skin model. Given the good sampling and in situ monitoring ability, the MN array holds great promise for skin ISF-based applications.
Subject(s)
Extracellular Fluid , Needles , Animals , Biomarkers , Gelatin , Skin , SwineABSTRACT
As a water storage lake for the South-to-North Water Diversion Project, it is crucial to examine changes in aquatic ecosystem structures in Lake Luoma, Jiangsu province. Field sampling was carried out in Lake Luoma monthly from 2014 to 2018 to study the relationship between the phytoplankton community structure and environmental factors. During the studied period, total nitrogen, permanganate index, and electrical conductivity in water column gradually increased, whereas fluoride content declined. The pattern of total phosphorus and dissolved oxygen was not distinct. A total of 71 genera of phytoplankton were identified from 2014 to 2018, and the average monthly biomass variation ranged from 0.16 to 5.51 mg·L-1. Bacillariophyta and Chlorophyta were the dominant phyla in the four years, followed by Pyrrophyta and Cryptophyta. The dominant genera were Synedra sp., Chroomonas spp., Aulacoseira spp., Dinobryon sp., Scenedesmus spp. , Fragilaria spp., Mougeotia sp. , Ankistrodesmus sp. , and Euglena spp. The results showed that the phytoplankton community structure significantly changed in the four years, which was mainly ascribed to the redistribution of biomass. Specifically, in addition to the dominance of Bacillariophyta and Chlorophyta, the dominance of Pyrrophyta and Cyanophyta increased during the last two years. Non-metric multidimensional scaling analysis showed that variation of the phytoplankton community in Lake Luoma was mainly related to total nitrogen, fluoride, water temperature, total phosphorus, dissolved oxygen, pH, conductivity, and permanganate index, among which the total nitrogen, water temperature, and fluoride concentration dominated the phytoplankton community change after the generalized additive model test. Water temperature is the driving factor affecting seasonal changes of the phytoplankton community. Total nitrogen and fluoride concentrations are the driving factors affecting the interannual variation in the phytoplankton community. Our study indicated that in recent years, the implementation of the ban on sand mining and demolition of the enclosed aquaculture in Lake Luoma has affected the water environment, resulting in a significant succession of the phytoplankton community.
Subject(s)
Lakes , Phytoplankton , China , Ecosystem , Environmental Monitoring , Nitrogen/analysis , Phosphorus/analysis , SeasonsABSTRACT
In this study, a facile and green method is described for decoration of ordered mesoporous carbon (OMC) with palladium nanoparticles (Pd NPs) through a polyoxometalates (POMs). Serving as both reducing and stabilizing agent, the Keggin-type POMs are used for synthesis of stable colloidal Pd NPs and then link them to the OMC at mild temperature. Current research focuses on the use of Pd-POMs-OMC as an effective sensing template for the detection of acetaminophen (AP) has been studied. Linear calibration curves in the range of 0.10-33.15µM (R2=0.998) was obtained for AP with a sensitivity of 985.4µAmM-1; the limit of detection was calculated to be 0.069µM. Importantly, the successful fabricated Pd-POMs-OMC device accurately measured the amount of AP in pharmaceutical samples.
Subject(s)
Acetaminophen/analysis , Analgesics, Non-Narcotic/analysis , Carbon/chemistry , Metal Nanoparticles/chemistry , Palladium/chemistry , Pharmaceutical Preparations/chemistry , Tungsten Compounds/chemistry , Electrodes , PorosityABSTRACT
A simple and sensitive electrochemical sensor is constructed for the detection of chlorogenic acid (CGA) based on Au nanoparticles (NPs)/polyoxometalates/3D macroporous carbon (Au-POMs-MPC). Serving as both a reducing and stabilizing agent, the Keggin-type POM, H3PW12O40, is used for the synthesis of stable colloidal Au NPs and then used to link them to MPC at a mild temperature. Because of the unique structural properties and synergetic catalytic effect, Au-POMs-MPC can be developed as an effective sensing platform for the detection of CGA, which showed high activity and excellent analytical performance towards CGA, such as a wide linear range of 2.28 nM-3.24 µM, a high sensitivity of 30 554.71 µA mM-1, and a low limit of detection of 2.15 nM. Importantly, the successfully fabricated Au-POMs-MPC device accurately measured the amount of CGA in pharmaceutical samples.
Subject(s)
Carbon , Chlorogenic Acid/analysis , Gold , Metal Nanoparticles , Pharmaceutical Preparations/analysis , Tungsten Compounds , Electrochemical TechniquesABSTRACT
Photodynamic therapy (PDT) has been considered to be a possible candidate approach in combating multidrug resistance (MDR) phenomenon during the treatment of cancer. To investigate the photocytotoxicity of a novel porphyrin-based photosensitizer, meso-5-[ρ-DTPA-aminophenyl]-10, 15, 20-triphenyl-porhyrin (DTP) (Fig. 1A), on MDR cells, the intracellular DTP uptake, phototoxicity and subcellular DTP localization were studied by using a human gastric cancer MGC803 cell line and its paclitaxel selected subline MGC803/PA expressing MDR phenotype. No significant difference was observed in intracellular DTP accumulation between sensitive and resistant cell lines after exposure to 1.56 µM concentration for 6h. DTP-PDT induced significant photocytotoxicity on both MGC803 and MGC803/PA cell lines and the photokilling was greater in MGC803 cell line in comparison to MGC803/PA. The fluence that caused 50% cell death was 4.42 and 6.29 J/cm(2) in MGC803 and MGC803/PA cell lines, respectively. The presence of Pgp inhibitors verapamil and cyclosporin A could not modify the intracellular DTP level in MGC803/PA cell line and the phototoxic effects. DTP was localized at lysosomes of MGC803 cell line but at lysosomes and mitochondria of MGC803/PA. Our results indicated that DTP-mediated PDT could eradicate gastric cancer cells whether or not they express MDR although the efficacy is slightly reduced in the MDR cells. The photokilling in MDR cells could not be altered by MDR inhibitor verapamil. The slightly different photocytotoxicity between sensitive and resistant cell lines could not explained by classical Pgp MDR and might be attributed to the differential intracellular DTP localization sites.
Subject(s)
Photochemotherapy/methods , Photosensitizing Agents/pharmacology , Porphyrins/pharmacology , Stomach Neoplasms/drug therapy , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Cell Line, Tumor , Drug Resistance, Multiple/drug effects , Drug Resistance, Neoplasm/drug effects , Humans , Paclitaxel/pharmacology , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacokinetics , Porphyrins/chemistry , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathologyABSTRACT
OBJECTIVE: The aim of the present study was to explore the association of the functional single-nucleotide polymorphism (SNP) rs3746804 in C20orf54 with the susceptibility to esophageal squamous cell carcinoma (ESCC). METHODS: SNP rs3746804 in C20orf54 was detected by direct sequencing in 434 ESCC patients and 554 healthy controls from Shanxi and Henan Provinces in China, geographically a high incidence area for ESCC. The frequencies and distribution of TT, CT, and CC genotypes of SNP rs3746804 between those 2 cohorts were compared and its association with ESCC was assessed. RESULTS: For SNP rs3746804 the genotype distribution of CT and CC in ESCC patients both significantly differed from those in healthy controls (p=0.002, 0.001, respectively), while the distribution of TT did not differ significantly between the groups (p=0.757). The ratio of T:C was high in healthy individuals and low in ESCC patients. Compared to genotype CC, both genotypes CT (odds ratio (OR)=0.63, 95% confidence interval (CI) 0.48l-0.826), and CT+TT (OR=0.654, 95% CI 0.507-0.844) were associated with significantly decreased risk for ESCC. CONCLUSION: A close association exists between functional SNP rs3746804 in C20orf54 and susceptibility to ESCC.
Subject(s)
Carcinoma, Squamous Cell/genetics , Esophageal Neoplasms/genetics , Membrane Transport Proteins/genetics , Polymorphism, Single Nucleotide/genetics , China/epidemiology , DNA/isolation & purification , Female , Genetic Predisposition to Disease/genetics , Genome-Wide Association Study/methods , Genotyping Techniques/methods , Humans , Male , Polymerase Chain ReactionABSTRACT
ATP-binding-cassette (ABC) proteins have been recognized as key players in cellular physiological transport processes. ABC transporter A6 (ABCA6) is a member of the ABC subfamily A. Although it was cloned more than 10 years ago, its expression regulation, subcellular localization, and physiologic function remain largely unknown. We here demonstrated that expression of ABCA6 was Forkhead box O (FoxO)-dependent in human endothelial cell line EA.hy926 and human umbilical vein endothelial cells. Two functional FoxO-responsive elements were identified in ABCA6 promoter and characterized in detail. ABCA6 mRNA was suppressed by insulin-like growth factor-1 which stimulates the phosphorylation and inactivation of FoxOs while inhibitor of phosphatidylinositol 3-kinase had the opposite effect. By immunofluorescence and confocal microscopy, ABCA6 protein is localized primarily in an intracellular compartment, likely representing the Golgi apparatus. ABCA6 mRNA was demonstrated to be responsive to cholesterol loading as well as 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase inhibitors in human endothelial cells. Our data provide evidence for an essential role of FoxO proteins in the transcription of ABCA6 in human vascular endothelial cells. Based on its cholesterol responsiveness, a potential involvement of ABCA6 in intracellular lipid transport processes may be anticipated.
Subject(s)
ATP-Binding Cassette Transporters/metabolism , Cholesterol/pharmacology , Forkhead Transcription Factors/metabolism , Intracellular Space/metabolism , ATP-Binding Cassette Transporters/genetics , Animals , Base Sequence , Binding Sites , Forkhead Box Protein O1 , Forkhead Box Protein O3 , Gene Expression Regulation/drug effects , HEK293 Cells , Human Umbilical Vein Endothelial Cells , Humans , Intracellular Space/drug effects , Mice , Molecular Sequence Data , Promoter Regions, Genetic/genetics , Protein Binding/genetics , Protein Transport/drug effects , Recombinant Fusion Proteins/metabolism , Signal Transduction/drug effects , Signal Transduction/genetics , Subcellular Fractions/drug effects , Subcellular Fractions/metabolismABSTRACT
DEPP was initially cloned from the human endometrial stromal cell cDNA library, but the transcriptional regulation of DEPP remains largely unknown. We demonstrate here that expression of DEPP is FoxO-dependent in human endothelial cells. Two functional FoxO-responsive elements are identified in the DEPP promoter. Hypoxia stimulates DEPP expression in the endothelial cell line EA.hy926. Hypoxia-induced upregulation of DEPP is dependent on FoxO expression. We conclude that DEPP is regulated at the level of transcription by FoxO in human vascular endothelial cells.
Subject(s)
Endothelial Cells/metabolism , Forkhead Transcription Factors/physiology , Gene Expression Regulation , Proteins/genetics , Transcription Factors/physiology , Cell Cycle Proteins , Endothelium, Vascular/cytology , Female , Forkhead Box Protein O1 , Forkhead Box Protein O3 , Humans , Hypoxia/genetics , Intracellular Signaling Peptides and Proteins , Promoter Regions, Genetic , Transcription, GeneticABSTRACT
AIM: To examine whether the phosphorylation of the O subfamily of forkhead transcription factors (FoxO) is involved in response to oxidative stress in rat aortic endothelial cells (RAECs). METHODS: RAECs were treated with H(2)0(2) and phosphorylation status of proteins were evaluated by Western blot analysis. The subcellular localization of FoxO1 was determined by nuclear and cytosolic fractionation followed by Western blot analysis as well as immunocytochemistry. The transcriptional activity of FoxO1 in H(2)0(2) stress was assessed by luciferase reporter assay. Expression of FoxO1 target gene was determined by real-time PCR analysis. RESULTS: H(2)0(2) stress stimulated phosphorylation of FoxO1 at Thr24 and Ser256 in a concentration and time dependent manner in RAECs. Pretreatment of RAECs with PI-3K inhibitors abolished the activation of Akt and prevented the phosphorylation of FoxO1. Akt-mediated phosphorylation promoted nuclear exclusion of FoxO1. An IRS-driven luciferase activity transactivated by exogenous FoxO1 was modestly suppressed by hydrogen peroxide stress. The expression of Bim, a target gene of FoxO factors, was negatively regulated by Akt-mediated phosphorylation in response to hydrogen peroxide stimulation. CONCLUSION: Our data demonstrate that phosphorylation of FoxO1 by PI-3K/Akt signaling is implicated in response to oxidative stress in vascular endothelial cells.