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Castor (Ricinus communis L.) is an importance crop cultivated for its oil and economic value. Seed size is a crucial factor that determines crop yield. Gaining insight into the molecular regulatory processes of seed development is essential for the genetic enhancement and molecular breeding of castor. Here, we successfully fine-mapped a major QTL related to seed size, qSS3, to a 180â kb interval on chromosome 03 using F2 populations (DL01×WH11). A 17.6-kb structural variation (SV) was detected through genomic comparison between DL01 and WH11. Analysis of haplotypes showed that the existence of the complete 17.6â kb structural variant may lead to the small seed characteristic in castor. In addition, we found that qSS3 contains the microRNA396b (miR396b) sequence, which is situated within the 17.6â kb SV. The results of our experiment offer additional evidence that miR396-Growth Regulating Factor 4 (GRF4) controls seed size by impacting the growth and multiplication of seed coat and endosperm cells. Furthermore, we found that RcGRF4 activates the expression of YUCCA6 (YUC6), facilitating the production of IAA in seeds and thereby impacting the growth of castor seeds. Our research has discovered a crucial functional module that controls seed size, offering a fresh understanding of the mechanism underlying seed size regulation in castor.
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Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , MicroRNAs , Sementes , MicroRNAs/genética , MicroRNAs/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Ácidos Indolacéticos/metabolismo , Locos de Características Quantitativas/genética , Ricinus communis/genética , Ricinus communis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ricinus/genética , Ricinus/metabolismo , Ricinus/crescimento & desenvolvimento , RNA de Plantas/genética , RNA de Plantas/metabolismoRESUMO
Oxygen vacancy (Ov) is known to act as an active center of the metal oxide. Quantification of surface Ov is vital for understanding the quantitative structure-activity relationship. Facile quantification characterization of surface Ov is highly desirable but still challenging. In this study, we presented a simple colorimetric method for rapidly quantifying surface Ov. As an example of metal oxide nanoparticles, Co3O4 was used to catalyze the 3,3',5,5'-tetramethylbenzidine (TMB)-H2O2 colorimetric reaction. It was found that the absorbance of the TMB-H2O2 system was dependent on the surface Ov amount in Co3O4. The investigation of the mechanism showed that the Ov-dependent absorbance would be attributed to the activity of surface Ov to easily adsorb and dissociate H2O2 into a hydroxyl radical (â¢OH). The absorbance signal of the TMB-H2O2 system acted as a probe to estimate the surface Ov. This colorimetric measurement could be completed in less than 20 min. The Ov concentrations obtained by the proposed colorimetric method matched well with those obtained by X-ray photoelectron spectroscopy. This method does not require any complex operation and expensive equipment and can be performed in any ordinary chemical laboratory. So, this colorimetric method is expected to become an alternative approach for quantifying the surface Ov in metal oxide nanoparticles. This method will provide essential insights into the rational design and application of Ov.
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As a natural green catalyst, laccase has extensive application in the fields of environmental monitoring and pollutant degradation. However, susceptibility to environmental influences and poor reusability seriously hinder its application. To address these concerns, for the first time, manganese ion replaced copper ion as the active center to coordinate with guanosine monophosphate (GMP) for synthesizing mimic laccase with high catalytic activity. Compared with natural laccase, the laccase-like nanozyme (Mn-GMPNS) demonstrated superior thermal stability, acid-base resistance, salt tolerance, reusability, and substrate universality. Benefiting from the high catalytic activity of Mn-GMPNS, epinephrine, a significant neurotransmitter and hormone associated with numerous diseases, was visually detected within 10 min and a portable assay by smartphone. More encouragingly, Mn-GMPNS can efficiently degrade dye pollutants, achieving a decolorization rate over 70% within 30 min. Thus, the coordination between manganese ion and nucleotide demonstrated the potential in rational design of nanozymes with high catalytic activity, low cost, good stability, and good biocompatibility.
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Poluentes Ambientais , Lacase , Lacase/metabolismo , Nucleotídeos , Manganês , Smartphone , EpinefrinaRESUMO
OBJECTIVE: The accessibility issue of orphan drugs in China is prominent. Based on real-world data from a tier-one city in Northeast China, this study aims to analyze the current usage and affordability of orphan drugs for rare diseases. METHODS: The data was sourced from the health insurance claims data of a certain city from 2018 to 2021, including a total of 16 orphan drugs. The utilization of orphan drugs is assessed using four indicators: frequency of medical insurance claims, medication cost, defined daily doses (DDDs), and defined daily drug cost (DDDc). Affordability is measured using the concept of catastrophic health expenditure (CHE). RESULTS: Between January 2018 and December 2021, there were a total of 2,851 medical insurance claims in the city, with a total medication costs of $3.08 million. Overall, during the study, there was a year-on-year increase in the utilization frequency of individual rare disease drugs in the city, with DDDs rising from 140.22 in 2018 to 3983.63 in 2021. Additionally, the annual medication costs of individual drugs showed a consistent upward trend, increasing from $10,953.53 in 2018 to $120,491.36 in 2021. However, the DDDc of individual drugs decreased from $398.12 in 2018 to $96.65 in 2021.The number of sales and the amount of sales for orphan drugs in community pharmacies have significantly increased. Prior to medical insurance coverage, out of the 16 orphan drugs, 9 drugs had annual treatment costs exceeding CHE for urban residents, and 15 drugs had annual treatment costs exceeding CHE for rural residents. After medical insurance coverage, there were no drugs with out-of-pocket costs exceeding CHE for urban residents, while 8 drugs had out-of-pocket costs exceeding CHE for rural residents. Furthermore, both before and after medical insurance coverage, the four treatment drugs for idiopathic pulmonary arterial hypertension were more affordable compared to the four treatment drugs for multiple sclerosis. CONCLUSION: The usage frequency of orphan drugs in a certain city increased gradually, but the disease burden remained heavy. More policy support should be provided to the priority rare disease populations, and the rare disease medical security and diagnosis and treatment systems should be improved.
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Cobertura do Seguro , Seguro Saúde , Produção de Droga sem Interesse Comercial , Doenças Raras , Humanos , China , Doenças Raras/tratamento farmacológico , Produção de Droga sem Interesse Comercial/economia , Produção de Droga sem Interesse Comercial/estatística & dados numéricos , Cobertura do Seguro/estatística & dados numéricos , Seguro Saúde/estatística & dados numéricos , Custos de Medicamentos/tendências , Gastos em Saúde/estatística & dados numéricos , Bases de Dados Factuais , Acessibilidade aos Serviços de Saúde/estatística & dados numéricosRESUMO
Acetamiprid (ACE) is a highly effective broad-spectrum insecticide, and its widespread use is potentially harmful to human health and environmental safety. In this study, magnetic Fe3O4/carbon (Fe3O4/C), a derivative of metal-organic framework MIL-101 (Fe), was synthesized by a two-step calcination method. And a fluorescent sensing strategy was developed for the efficient and sensitive detection of ACE using Fe3O4/C and multiple complementary single-stranded DNA (ssDNA). By using aptamer with multiple complementary ssDNA, the immunity of interference of the aptasensor was improved, and the aptasensor showed high selectivity and sensitivity. When ACE was present, the aptamer (Apt) combined with ACE. The complementary strand of Apt (Cs1) combined with two short complementary strands of Cs1, fluorophore 6-carboxyfluorescein-labeled complementary strand (Cs2-FAM) and the other strand Cs3. The three strands formed a double-stranded structure, and fluorescence would not be quenched by Fe3O4/C. In the absence of ACE, Cs2-FAM would be in a single-chain state and would be adsorbed by Fe3O4/C, and the fluorescence of FAM would be quenched by Fe3O4/C via photoelectron transfer. This aptasensor sensitively detected ACE over a linear concentration range of 10-1000 nM with a limit of detection of 3.41 nM. The recoveries of ACE spiked in cabbage and celery samples ranged from 89.49% to 110.76% with high accuracy.
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Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Humanos , DNA de Cadeia Simples , Verduras , Neonicotinoides , Fluorescência , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Limite de DetecçãoRESUMO
BACKGROUND: The National Drug Price Negotiation (NDPN) policy has entered a normalisation stage, aiming to alleviate, to some extent, the disease-related and economic burdens experienced by cancer patients. This study analysed the use and subsequent burden of anticancer medicines among cancer patients in a first-tier city in northeast China. METHODS: We assessed the usage of 64 negotiated anticancer medicines using the data on the actual drug deployment situation, the frequency of medical insurance claims and actual medication costs. The affordability of these medicines was measured using the catastrophic health expenditure (CHE) incidence and intensity of occurrence. Finally, we used the defined daily doses (DDDs) and defined daily doses cost (DDDc) as indicators to evaluate the actual use of these medicines in the region. RESULTS: During the study period, 63 of the 64 medicines were readily available. From the perspective of drug usage, the frequency of medical insurance claims for negotiated anticancer medicines and medication costs showed an increasing trend from 2018 to 2021. Cancer patients typically sought medical treatment at tertiary hospitals and purchased medicines at community pharmacies. The overall quantity and cost of medications for patients covered by the Urban Employee Basic Medical Insurance (UEBMI) were five times higher than those covered by the Urban and Rural Resident Medical Insurance (URRMI). The frequency of medical insurance claims and medication costs were highest for lung and breast cancer patients. Furthermore, from 2018 to 2021, CHE incidence showed a decreasing trend (2.85-1.60%) under urban patients' payment capability level, but an increasing trend (11.94%-18.42) under rural patients' payment capability level. The average occurrence intensities for urban (0.55-1.26 times) and rural (1.27-1.74 times) patients showed an increasing trend. From the perspective of drug utilisation, the overall DDD of negotiated anticancer medicines showed an increasing trend, while the DDDc exhibited a decreasing trend. CONCLUSION: This study demonstrates that access to drugs for urban cancer patients has improved. However, patients' medical behaviours are affected by some factors such as hospital level and type of medical insurance. In the future, the Chinese Department of Health Insurance Management should further improve its work in promoting the fairness of medical resource distribution and strengthen its supervision of the nation's health insurance funds.
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Antineoplásicos , Custos de Medicamentos , Seguro Saúde , Humanos , China , Antineoplásicos/economia , Antineoplásicos/uso terapêutico , Custos de Medicamentos/estatística & dados numéricos , Seguro Saúde/economia , Seguro Saúde/estatística & dados numéricos , Neoplasias/tratamento farmacológico , Neoplasias/economia , Feminino , Masculino , Negociação , Gastos em Saúde/estatística & dados numéricos , Pessoa de Meia-IdadeRESUMO
A chemiluminescence (CL) method for determination of glutathione (GSH) was developed with magnetic nanoparticle-decorated metal organic frameworks (Fe3O4 NPs@Cu-TATB). The composite material was synthesized via a hydrothermal method and glutathione (GSH) can be detected by both visual and chemiluminescence (CL) methods. The synthesized Fe3O4 NPs@Cu-TATB exhibited excellent catalytic activity in the luminol-H2O2 CL system. The mechanism revealed that three types of oxygen-containing radicals (ROS) were generated in this system. As GSH can reduce the catalytic effect of generated ROS radicals, the inhibiting CL signal was produced in the Fe3O4 NPs@Cu-TATB-luminol-H2O2 system. Based on the established CL system, the detection limits for GSH using CL and visual methods were found to be 0.3 µM and 0.7 µM, respectively. This low-cost and convenient detection method can be applied to the determination of GSH content in human blood.
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Glutationa , Peróxido de Hidrogênio , Limite de Detecção , Medições Luminescentes , Luminol , Nanopartículas de Magnetita , Estruturas Metalorgânicas , Glutationa/sangue , Glutationa/química , Glutationa/análise , Humanos , Estruturas Metalorgânicas/química , Medições Luminescentes/métodos , Luminol/química , Nanopartículas de Magnetita/química , Peróxido de Hidrogênio/química , Cobre/química , CatáliseRESUMO
Chiral nanoparticles are one of the research hotspots in the field of materials science, chemistry, and biology. Understanding and controlling the chirality of nanoparticles is one key step toward their use, but the origin of nanoparticles' chirality and its determinative factor are not well understood. In this work, we studied the chirality of gold nanoparticles (AuNPs) prepared through the conventional citrate reduction method. Unexpectedly, it was found that small AuNPs (â¼13 nm) exhibited opposite chirality to the large AuNPs (>30 nm). The origin of the AuNPs chirality was revealed by comparing the crystal structure between small AuNPs and large AuNPs. It was proposed that the lattice orientation of fivefold-twinned AuNPs may be responsible for the intrinsic chirality of AuNPs. This work provides a deep mechanistic understanding of the intrinsic chirality of the AuNPs and will boost the development of the structure-controlled synthesis and application of chiral AuNPs and other chiral nanomaterials. Furthermore, based on the unexpected size effect, chiral AuNP probes were rationally constructed to improve the precision of chiral recognition.
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The classic luminol-H2O2 chemiluminescence (CL) systems suffer from easy self-decomposition of H2O2 at room temperature, hindering the practical applications of the luminol-H2O2 CL system. In this work, unexpectedly, we found that the carbon vacancy-modified Fe-N-C single atom catalysts (VC-Fe-N-C SACs) can directly trigger a luminol solution to generate strong CL emission in the absence of H2O2. The Fe-based SACs were prepared through the conventional pyrolysis of zeolitic imidazolate frameworks. The massive carbon vacancies were readily introduced into Fe-N-C SACs through a tannic acid-etching process. Carbon vacancy significantly enhanced the catalytic activity of Fe-N-C SACs on the CL reaction of luminol-dissolved oxygen. The VC-Fe-N-C SACs performed a 13.4-fold CL enhancement compared with the classic luminol-Fe2+ system. It was found that the introduction of a carbon vacancy could efficiently promote dissolved oxygen to convert to reactive oxygen species. As a proof of concept, the developed CL system was applied to detect alkaline phosphatase with a linear range of 0.005-1 U/L as well as a detection limit of 0.003 U/L. This work demonstrated that VC-Fe-N-C SAC is a highly efficient CL catalyst that can promote the analytic application of the luminol CL system.
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Oxygen vacancy is one intrinsic defect in metal oxide materials. Interestingly, we herein found that the surface oxygen vacancy can significantly enhance the catalytic activity of Co3O4 nanowires in the luminol-H2O2 chemiluminescence (CL) reaction. 0.1 ng/mL Co3O4 nanowires containing 51.3% surface oxygen vacancies possessed ca. 2.5-fold catalytic activity of free Co2+ (the best metal ionic catalyst for the luminol-H2O2 CL reaction). The superior catalytic efficiency is attributed to the enhanced adsorption of H2O2 by surface oxygen vacancies, which in turn accelerates the cleavage of O-O bonds and generates â¢OH radicals. More importantly, the surface oxygen vacancy-rich Co3O4 nanowires retained about 90% catalytic activity after modification with antibodies. The surface oxygen vacancy-rich Co3O4 nanowires were used to label the secondary antibody, and one sandwich-type CL immunoassay of carcinoembryonic antigen was established. The detection limit was 0.3 ng/mL with a linear range of 1-10 ng/mL. This proof-of-concept work proves that surface oxygen vacancy-rich Co3O4 nanowires are suitable for labeling biomolecules in CL bioanalysis and biosensing.
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Luminol , Nanofios , Luminol/química , Peróxido de Hidrogênio/análise , Oxigênio , Luminescência , Imunoensaio , AnticorposRESUMO
Volatile formaldehyde (FA) in exhaled breath (EB) is considered as a biomarker for lung cancer (LC). On-the-spot selective and sensitive detection of gaseous FA is rather important for LC screening and diagnosis. Herein, a tetrakis(4-pyridylphenyl)ethylene (Py-TPE)-based zinc metal-organic framework (MOF) with excellent aggregation-induced emission (AIE) property was utilized for absorption and selective detection of FA in EB. The porous Zn-Py-TPE served as a gaseous confinement cavity for the adsorption of FA in EB. Interestingly, Zn-Py-TPE was aggregated on paper, and then aggregation-induced chemiluminescence (CL) emission can be triggered by only adding bis(2,4,6-trichlorophenyl)oxalate (TCPO). Though without H2O2, the CL of Zn-Py-TPE-TCPO was enhanced greatly by FA. FA promoted the aggregation of Zn-Py-TPE on paper by forming halogen bonding between FA and Zn-Py-TPE, which contributed to the better selectivity. FA can also stimulate the production of more singlet oxygen (1O2) in the Zn-Py-TPE-TCPO CL system. Hence, FA could be detected via the proposed Zn-Py-TPE-TCPO system with a quantification linear range of 1.0-100.0 ppb and detection limit of 0.3 ppb. This portable, low-cost, and sensitive paper-based platform can achieve trace FA detection in EB and is expected to provide an on-the-spot screening platform for lung cancer.
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Neoplasias Pulmonares , Estruturas Metalorgânicas , Humanos , Luminescência , Zinco , Peróxido de Hidrogênio , Etilenos , Neoplasias Pulmonares/diagnóstico , FormaldeídoRESUMO
Receptors are crucial to the analytical performance of sensor arrays. Different from the previous receptors in sensor arrays, herein, peroxidase-mimicking DNAzymes were innovatively used as receptors to develop a label-free chemiluminescence sensor array for discriminating various heavy metal ions in complex samples. The peroxidase-mimicking DNAzymes are composed of functional oligonucleotides and hemin, including G-triplex-hemin DNAzyme (G3-DNAzyme), G-quadruplex-hemin DNAzyme (G4-DNAzyme), and the dimer of G-quadruplex-hemin DNAzyme (dG4-DNAzyme). Circular dichroism (CD) spectroscopy demonstrated that different metal ions diversely affect the conformation of G-quadruplex and G-triplex, resulting in a change in the activity of peroxidase-mimicking DNAzyme. Thus, the unique fingerprints formed to easily discriminate seven kinds of heavy metal ions by principal component analysis (PCA) within 20 min. The discrimination of unknown metal ions in tap water further confirmed its ability for discriminating multiple heavy metal ions. Moreover, it will not bring water pollution due to the good biocompatibility of DNA. Therefore, it not only merely offers a label-free, rapid, environment-friendly, and cheap (1.49 $) sensor assay for discriminating metal ions but also comes up with an innovative way for developing sensor arrays.
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Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , DNA Catalítico/química , Peroxidase/química , Hemina/química , Luminescência , Peroxidases/química , Metais , Íons , Técnicas Biossensoriais/métodosRESUMO
Molecular logic gate provides an intelligent option for simultaneous detection of biomarkers. Herein, a dual-mode DNA logic gate was proposed to portably and intelligently detect multiple microRNAs (miRNAs) by gas pressure biosensing and lateral flow assay (LFA). A platinum-coated gold nanoparticle (Au@PtNP) with catalase-like activity was used as a signal reporter to achieve a dual-signal readout. MiRNAs as the input initiated the cyclic strand displacement reaction (SDR) to enrich a large amount of Au@PtNPs. Thus, miRNA can be visually detected by a lateral flow strip (LFS) using the grayish-brown color of Au@PtNPs as output 1. Furthermore, Au@PtNP-catalyzed decomposition of H2O2 resulted in gas pressure as output 2, which was measured by a digital and handheld gas pressure meter. As a consequence, microRNA 21 (miR-21) was sensitively and reliably detected with the limit of detection (LOD) of 7.2 pM. The selectivity and real sample analysis were both satisfactory. Significantly, two-input and three-input AND logic gates were successfully developed to realize multiple detection of two miRNAs and three miRNAs, which provide a promising way for intelligent multi-input analysis. Predictably, with the advantages of portability, simplicity, and affordability, the dual-mode logic gate based on gas pressure biosensing and LFA offers a new perspective on the field of intelligent and portable biosensing and bioanalysis.
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Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , MicroRNAs/análise , Ouro , Peróxido de Hidrogênio , Técnicas Biossensoriais/métodosRESUMO
In situ synthesis of metal-organic frameworks (MOFs) on flexible materials for the fabrication of functional platforms and micro-devices is challenging. The time-/precursor-consuming procedure and uncontrollable assembly are stumbling blocks for constructing this platform. Herein, a novel in situ MOF synthesis method on paper substrates by use of the ring-oven-assisted technique was reported. Utilizing the ring-oven's heating and washing function, MOFs can be synthesized in 30 min on the designated position of paper chips with extremely low-volume precursors. The principle of this method was explained by steam condensation deposition. The MOFs' growth procedure was theoretically calculated by crystal sizes and the results conformed to the Christian equation. As different MOFs (Cu-MOF-74, Cu-BTB, Cu-BTC) can be synthesized successfully on paper-based chips, the ring-oven-assisted in situ synthesis method has great generality. Then, the prepared Cu-MOF-74 loading paper-based chip was applied to the chemiluminescence (CL) detection of nitrite (NO2-), based on the catalysis effect of Cu-MOF-74 on the NO2--H2O2 CL system. Also, by the delicate design of the paper-based chip, NO2- can be detected with the detection limit (DL) of 0.5 nM in whole blood samples without sample pretreatment. This work establishes a distinctive method for the in situ synthesis of MOFs and the application of MOFs on paper-based CL chips.
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Estruturas Metalorgânicas , Nitritos , Peróxido de Hidrogênio , Luminescência , Dióxido de NitrogênioRESUMO
DNA logic gates have shown outstanding magic in intelligent biology applications, but it remains challenging to construct a portable, affordable and convenient DNA logic gate. Herein, logic gates of gas pressure were innovatively developed for multiplex analysis of metal ions. Hg2+ and Ag+ were input to interact specifically with the respective mismatched base pairs, which activated DNA extension reaction by polymerase and led to the enrichment of platinum nanoparticles for catalyzing the decomposition of peroxide hydrogen. Thus, the gas pressure obtained from a sealed well was used as output for detecting or identifying metal ions. Hg2+ and Ag+ were sensitively and selectively detected, and the assay of the real samples was also satisfactory. Based on this, DNA logic gates, including YES, NOT, AND, OR, NAND, NOR, INHIBIT, and XOR were successfully established using a portable and hand-held gas pressure meter as detector. So, the interactions between DNA and metal ions were intelligently transferred into the output of gas pressure, which made metal ions to be detected portably and identified intelligently. Given the remarkable merits of simplicity, logic operation, and portable output, the metal ion-driven DNA logic gate of gas pressure provides a promising way for intelligent and portable biosensing.
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Mercúrio , Nanopartículas Metálicas , Platina , Mercúrio/análise , DNA , ÍonsRESUMO
Gas pressure biosensing is a promising portable analysis method. The gas-generation reaction is crucial to its sensitivity, speed, repeatability, and usability. However, very few gas-generation reactions are available for sensitive, safe, and diverse biosensing. Herein, acid-accelerated hydrolysis of sodium borohydride (NaBH4) was explored for the first time to achieve portable and diverse gas pressure biosensing. The slow hydrolysis and hydrogen generation of NaBH4 in alkaline medium is accelerated with increasing acidity, which increased the gas pressure in a small and sealed tube within 10 min. Thus, a label-free bioassay is easily and specifically achieved once analytes can in-situ generate acid to accelerate the hydrolysis rate of NaBH4, such as glucose, acetylcholine (ACh), adenosine triphosphate (ATP) and others. More importantly, analytes without acid generation could be quantitatively and selectively detected by combining target recognition with acid-generated biochemical reactions for enzyme-linked gas pressure biosensing. Inspired by this, aflatoxin B1 (AFB1)-aptamer interaction-triggered strand displacement reaction was combined with glucose oxidation by glucose oxidase (GOD) to detect AFB1 as low as 7.1 pM. Therefore, acid-accelerated hydrolysis of NaBH4 is powerful for developing portable, cheap, and diverse gas pressure biosensing. It opens up a new way for cheap, universal, and portable biosensing.
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Aflatoxina B1 , Glucose , Hidrólise , Aflatoxina B1/análise , Oxirredução , OligonucleotídeosRESUMO
An unsophisticated fluorescence-enabled strategy is brought forward to process the highly sensitive fluorescence detection of Salmonella typhimurium (S. typhimurium) which based on polyethyleneimine (PEI)-templated silver/copper nanoclusters (Ag/CuNCs) (λ excitation = 334 nm and λ emission = 466 nm) with cryonase-assisted target recycling amplification. The Ag/CuNCs nanoclusters are synthesized as fluorescent materials due to their strong and stable fluorescence characteristics and are modified with S. typhimurium aptamers to form aptamer-Ag/CuNCs probes. The probes can be adsorbed on the surface of quenching agents-polydopamine nanospheres (PDANSs), thereby inducing fluorescence quenching of the probes. Once the aptamers are bound to the target, the aptamers/targets complexes are separated from the PDANSs surface, and the Ag/CuNCs recover the fluorescence signal. The released complexes will immediately be transformed into a substrate digested by cryonase (an enzyme that can digest all types of nucleic acids), and the released targets are bound to another aptamers to initiate the next round of cleavage. This reaction will be repeated continuously until all relevant aptamers are consumed and all Ag/CuNCs are released, resulting in a significant amplification of the fluorescence signal and improved sensitivity. Using Ag/CuNCs as fluorescent probes combined with cryonase-assisted amplification strategy, the fluorescence aptasensor is constructed with detection limits as low as 3.8 CFU mL-1, which is tenfold better than without the cryonase assistance. The method developed has been applied to milk, orange juice, chicken, and egg white samples with excellent selectivity and accuracy providing an approach for the early and rapid detection of S. typhimurium in food.
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Cobre , Salmonella typhimurium , Animais , Prata , Galinhas , Corantes Fluorescentes , OligonucleotídeosRESUMO
Nucleic acid lateral flow assay (NALFA) with gold nanoparticles (AuNPs) as colorimetric probes have been extensively adopted for point-of-care testing (POCT). However, the sensitivity of NALFA still needs to be improved. Herein, DNA-gold nanoaggregate (DNA-AuNA) was assembled as a signal amplification probe of NALFA for sensitive detection of tumor marker TK1 mRNA. Four functional oligonucleotides with complementary pairs were assembled to form DNA-AuNA that coupled more AuNPs to improve sensitivity. Thus, the limit of detection (LOD) was 0.36 pM, which is lower than that of conventional AuNPs-based NALFA. Moreover, the bioassay showed good reproducibility, stability, and specificity for detecting TK1 mRNA. The detection of TK1 mRNA in human serum was also satisfactory. Therefore, DNA-AuNA-based NALFA provides a sensitive method for portable detection of TK1 mRNA.
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Ouro , Nanopartículas Metálicas , Humanos , Reprodutibilidade dos Testes , DNA/genéticaRESUMO
Objective: This study aimed to explore the impact of hyperkalemia at admission on hospitalization days (HDs) among advanced chronic kidney disease patients (CKD) with type two diabetes mellitus (T2DM) in China. Methods: A total of 270 CKD patients with T2DM were prospectively selected from January 1, 2020 to December 31, 2021. These patients were divided into Group-A (n = 150, serum potassium ≤ 5.5 mmol/L) and B (n = 120, serum potassium > 5.5 mmol/L). The comparison method between the two groups was taken. Linear correlation analysis was performed using the Spearman correlation method, and multivariate analysis was tested using linear regression. Results: The study found statistically significant result between the two groups (Group-A vs Group-B): HDs (7.4 (5.3-11.2) vs 12.1 (8.2-16.5), p < 0.001), renin-angiotensin-aldosterone system inhibitors (RAASIs) (36.2% vs 55.8%, p = 0.014), systolic blood pressure (148.35 ± 19.51 vs 162.26 ± 21.31, p < 0.05), estimated glomerular filtration (eGFR) (20.35) (18.31-25.26) vs13.4 (12.50-18.50), p < 0.001, N-terminal pro-B type natriuretic peptide (NT-proBNP) (2245.42 ± 61.09 vs 3163.39 ± 85.15,p < 0.001), and Hb (88.45 ± 12.35 vs 72.26 ± 14.2, p = 0.023). Correlation analysis showed that HDs were positively correlated with age, serum potassium, systolic blood pressure, and NT-proBNP, while negatively with eGFR and Hb. After adjusting for relevant confounding variables, the multivariable linear regression analysis showed that hyperkalemia was an independent risk factor for HDs. Conclusions: Hyperkalemia could be an independent risk factor increasing HDs of advanced CKD patients with T2DM.
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Defect engineering is an effective strategy to improve the catalytic activity of metal oxides, and quantitative characterization of surface defects is thus vital to the understanding and application of metal oxide catalysts. Herein, we found that ZnO nanoparticles with oxygen vacancy could trigger the luminol-H2O2 system to emit a strong chemiluminescence (CL), and the CL intensity was strongly dependent on the oxygen vacancy of the ZnO nanoparticles. The mechanism of this CL reaction was discussed by means of the electron-spin resonance spectrum, X-ray photoelectron spectrum (XPS), and CL spectrum. The oxygen vacancy-dependent CL was attributed to the ability of the oxygen vacancy to readily adsorb and further dissociate H2O2 into active â¢OH radicals. Taking advantage of this oxygen vacancy-dependent CL, we presented one method for quantifying the oxygen defects in ZnO. Compared with the current evaluation techniques (XPS and Raman spectroscopy), this CL method is rapid, low-cost, and easy to operate. This work introduces the CL technique into the field of material structure-property evaluation, and provides a new approach for exploring the defect function in ZnO defect engineering.