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Traditionally, a relatively big urine volume (e.g., 500 µL) is used in nuclear magnetic resonance (NMR)-based human metabolomics, which is not feasible for studies with limited/precious samples. Although urine may be diluted before conventional high-throughput metabolomics analysis, the comprehensive effect of urine dilution on metabolic profiles is unknown. Here, for the first time, we systematically investigated the effect of urine dilution on 1H NMR metabolic profiles, by evaluating signal detectability, integration, signal-to-noise ratio (SNR), chemical shift (δ) and its variation, and signal overlapping of 47 metabolites in 10 volunteers. We observed significant linear changes along with increased dilution, including decreased integration and SNR, altered δ, decreased intersample variation of δ, and increased separation between overlapped signals, e.g., lactate and threonine, ß-d-glucose and an unassigned signal, and histidine and 3-methylhistidine. We further tested the 40% dilution level (i.e., employing 300 µL urine) in an epidemiological study containing 1018 pregnant women from the Tongji-Shuangliu Birth Cohort, showing acceptable detectability and chemical shift variability for most of the 47 metabolites profiled. It indicated that mild (e.g., 40%) dilution of human urine can largely preserve the high-abundance metabolites profiled, reduce intersample chemical shift variations, and increase separations of overlapped signals, which is an improvement of routine sample preparation methods in NMR-based metabolomics and is applicable for studies with limited urine volumes, including large-scale epidemiological studies.
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Imageamento por Ressonância Magnética , Metabolômica , Gravidez , Humanos , Feminino , Ácido Láctico , Espectroscopia de Ressonância Magnética , MetabolomaRESUMO
BACKGROUND: Diabetic Retinopathy (DR) is the most common and serious microvascular complication in the diabetic population. Using computer-aided diagnosis from the fundus images has become a method of detecting retinal diseases, but the detection of multiple lesions is still a difficult point in current research. METHODS: This study proposed a multi-label classification method based on the graph convolutional network (GCN), so as to detect 8 types of fundus lesions in color fundus images. We collected 7459 fundus images (1887 left eyes, 1966 right eyes) from 2282 patients (1283 women, 999 men), and labeled 8 types of lesions, laser scars, drusen, cup disc ratio ([Formula: see text]), hemorrhages, retinal arteriosclerosis, microaneurysms, hard exudates and soft exudates. We constructed a specialized corpus of the related fundus lesions. A multi-label classification algorithm for fundus images was proposed based on the corpus, and the collected data were trained. RESULTS: The average overall F1 Score (OF1) and the average per-class F1 Score (CF1) of the model were 0.808 and 0.792 respectively. The area under the ROC curve (AUC) of our proposed model reached 0.986, 0.954, 0.946, 0.957, 0.952, 0.889, 0.937 and 0.926 for detecting laser scars, drusen, cup disc ratio, hemorrhages, retinal arteriosclerosis, microaneurysms, hard exudates and soft exudates, respectively. CONCLUSIONS: Our results demonstrated that our proposed model can detect a variety of lesions in the color images of the fundus, which lays a foundation for assisting doctors in diagnosis and makes it possible to carry out rapid and efficient large-scale screening of fundus lesions.
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Retinopatia Diabética , Algoritmos , Retinopatia Diabética/diagnóstico por imagem , Exsudatos e Transudatos , Feminino , Fundo de Olho , Humanos , MasculinoRESUMO
BACKGROUND: Epilepsy is one of the diseases of the nervous system, which has a large population in the world. Traditional diagnosis methods mostly depended on the professional neurologists' reading of the electroencephalogram (EEG), which was time-consuming, inefficient, and subjective. In recent years, automatic epilepsy diagnosis of EEG by deep learning had attracted more and more attention. But the potential of deep neural networks in seizure detection had not been fully developed. METHODS: In this article, we used a one-dimensional convolutional neural network (1-D CNN) to replace the residual network architecture's traditional convolutional neural network (CNN). Moreover, we combined the Independent recurrent neural network (indRNN) and CNN to form a new residual network architecture-independent convolutional recurrent neural network (RCNN). Our model can achieve an automatic diagnosis of epilepsy EEG. Firstly, the important features of EEG were learned by using the residual network architecture of 1-D CNN. Then the relationship between the sequences were learned by using the recurrent neural network. Finally, the model outputted the classification results. RESULTS: On the small sample data sets of Bonn University, our method was superior to the baseline methods and achieved 100% classification accuracy, 100% classification specificity. For the noisy real-world data, our method also exhibited powerful performance. CONCLUSION: The model we proposed can quickly and accurately identify the different periods of EEG in an ideal condition and the real-world condition. The model can provide automatic detection capabilities for clinical epilepsy EEG detection. We hoped to provide a positive significance for the prediction of epileptic seizures EEG.
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Eletroencefalografia , Epilepsia , Progressão da Doença , Epilepsia/diagnóstico , Humanos , Redes Neurais de Computação , ConvulsõesRESUMO
BACKGROUND: Epilepsy was defined as an abnormal brain network model disease in the latest definition. From a microscopic perspective, it is also particularly important to observe the Mutual Information (MI) of the whole brain network based on different lead positions. METHODS: In this study, we selected EEG data from representative temporal lobe and frontal lobe epilepsy patients. Based on Phase Space Reconstruction and the calculation of MI indicator, we used Complex Network technology to construct a dynamic brain network function model of epilepsy seizure. At the same time, about the analysis of our network, we described the index changes and propagation paths of epilepsy discharge in different periods, and spatially monitors the seizure change process based on the analysis of the parameter characteristics of the complex network. RESULTS: Our model portrayed the functional synergy between the various regions of the brain and the state transition during the seizure process. We also characterized the EEG synchronous propagation path and core nodes during seizures. The results shown the full node change path and the distribution of important indicators during the seizure process, which makes the state change of the seizure process more clearly. CONCLUSION: In this study, we have demonstrated that synchronization-based brain networks change with time and space. The EEG synchronous propagation path and core nodes during epileptic seizures can provide a reference for finding the focus area.
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Epilepsia , Convulsões , Encéfalo , Mapeamento Encefálico , Eletroencefalografia , HumanosRESUMO
Ovarian granulosa cells (GC) play an essential role in the development and atresia of follicles. Emerging studies suggest that non-coding RNAs are involved in the regulation of GC apoptosis. Here, we aimed to analyze the function of ssc-circINHA-001, coded by the first exon of the inhibin subunit α gene (INHA), in resisting GC apoptosis and follicular atresia by enhancing the expression of the inhibin subunit ß A (INHBA) through a cluster of miRNAs. A higher expression of ssc-circINHA-001 in healthy follicles compared to early atretic follicles was detected by qRT-PCR. Its circular structure was confirmed by RNase R treatment and reversed PCR. The function of ssc-circINHA-001 in GC resistance to apoptosis was detected by in vitro transfection of its si-RNA. Furthermore, the dual-luciferase reporter assay suggested that ssc-circINHA-001 adsorbed three miRNAs, termed miR-214-5p, miR-7144-3p, and miR-9830-5p, which share the common target INHBA. A low expression of ssc-circINHA-001 increased the levels of the free miRNAs, inhibited INHBA expression, and thus raised GCs apoptosis through a shift from the secretion of activin to that of inhibin. Our study demonstrated the existence of a circRNA-microRNAs-INHBA regulatory axis in follicular GC apoptosis and provides insight into the relationship between circRNA function and its coding gene in inhibin/activin balance and ovarian physiological functions.
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Ativinas/genética , Apoptose , Atresia Folicular/metabolismo , Células da Granulosa/metabolismo , Inibinas/genética , MicroRNAs/genética , RNA Circular/metabolismo , Animais , Feminino , Atresia Folicular/fisiologia , Regulação da Expressão Gênica , Células da Granulosa/fisiologia , Inibinas/metabolismo , MicroRNAs/metabolismo , Ovário/metabolismo , Ovário/fisiologia , Sus scrofa/genética , Sus scrofa/metabolismo , Sus scrofa/fisiologiaRESUMO
A highly sensitive electrochemiluminescent (ECL) aptasensor was constructed using semicarbazide (Sem) as co-reaction accelerator to promote the ECL reaction rate of CdTe quantum dots (CdTe QDs) and the co-reactant of peroxydisulfate (S2O8(2-)) for boosting signal amplification. The co-reaction accelerator is a species that when it is introduced into the ECL system containing luminophore and co-reactant, it can interact with co-reactant rather than luminophore to promote the ECL reaction rate of luminophore and co-reactant; thus the ECL signal is significantly amplified in comparison with that in which only luminophore and co-reactant are present. In this work, the ECL signal probes were first fabricated by alternately assembling the Sem and Au nanoparticles (AuNPs) onto the surfaces of hollow Au nanocages (AuNCs) via Au-N bond to obtain the multilayered nanomaterials of (AuNPs-Sem)n-AuNCs for immobilizing amino-terminated detection aptamer of thrombin (TBA2). Notably, the Sem with two -NH2 terminal groups could not only serve as cross-linking reagent to assemble AuNPs and AuNCs but also act as co-reaction accelerator to enhance the ECL reaction rate of CdTe QDs and S2O8(2-) for signal amplification. With the sandwich-type format, TBA2 signal probes could be trapped on the CdTe QD-based sensing interface in the presence of thrombin (TB) to achieve a considerably enhanced ECL signal in S2O8(2-) solution. As a result, the Sem in the TBA2 signal probes could accelerate the reduction of S2O8(2-) to produce the more oxidant mediators of SO4(â¢-), which further boosted the production of excited states of CdTe QDs to emit light. With the employment of the novel co-reaction accelerator Sem, the proposed ECL biosensor exhibited ultrahigh sensitivity to quantify the concentration of TB from 1 × 10(-7) to 1 nM with a detection limit of 0.03 fM, which demonstrated that the co-reaction accelerator could provide a simple, efficient, and low-cost approach for signal amplification and hold great potential for other ECL biosensors construction.
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Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Cobalto/química , Técnicas Eletroquímicas , Luminescência , Semicarbazidas/química , Trombina/análise , Compostos de Cádmio/química , Medições Luminescentes , Pontos Quânticos , Sulfatos/química , Telúrio/química , Trombina/metabolismoRESUMO
With the rapid global warming in recent decades, the Tibetan Plateau (TP) has suffered severe impacts, such as glacier retreat, glacial lake expansion, and permafrost degradation, which threaten the lives and properties of the local and downstream populations. Regional Reanalysis (RR) is vital for TP due to the limitations of observations. In this work, a 62-year (1961-2022) long atmospheric regional reanalysis with spatial resolution of 9 km (convective gray-zone scale) and temporal resolution of 1 hour over the TP (TPRR) was developed using the Weather Research and Forecasting (WRF) model, combined with re-initialization method, spectral nudging (SN), and several optimizations. TPRR is forced by ERA5 at hourly intervals. TPRR outperforms ERA5, realistically capturing climatological characteristics and seasonal variations of precipitation and T2m (air temperature at 2m above ground level). Moreover, TPRR better reproduces the frequency and intensity of precipitation, as well as the diurnal cycle of precipitation. This study also quantifies the wetting trend of 0.0071 mm/year over the TP amid global warming using TPRR.
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Importance: Improved understanding of trends in the proportion of individuals with metabolically healthy obesity (MHO) may facilitate stratification and management of obesity and inform policy efforts. Objectives: To characterize trends in the prevalence of MHO among US adults with obesity, overall and by sociodemographic subgroups. Design, Setting, and Participants: This survey study included 20â¯430 adult participants from 10 National Health and Nutrition Examination Survey (NHANES) cycles between 1999-2000 and 2017-2018. The NHANES is a series of cross-sectional and nationally representative surveys of the US population conducted continuously in 2-year cycles. Data were analyzed from November 2021 to August 2022. Exposures: National Health and Nutrition Examination Survey cycles from 1999-2000 to 2017-2018. Main Outcomes and Measures: Metabolically healthy obesity was defined as a body mass index of 30.0 (calculated as weight in kilograms divided by height in meters squared) without any metabolic disorders in blood pressure, fasting plasma glucose (FPG), high-density lipoprotein cholesterol (HDL-C), or triglycerides based on established cutoffs. Trends in the age-standardized prevalence of MHO were estimated using logistic regression analysis. Results: This study included 20â¯430 participants. Their weighted mean (SE) age was 47.1 (0.2) years; 50.8% were women, and 68.8% self-reported their race and ethnicity as non-Hispanic White. The age-standardized prevalence (95% CI) of MHO increased from 3.2% (2.6%-3.8%) in the 1999-2002 cycles to 6.6% (5.3%-7.9%) in the 2015-2018 cycles (P < .001 for trend). There were 7386 adults with obesity. Their weighted mean (SE) age was 48.0 (0.3) years, and 53.5% were women. The age-standardized proportion (95% CI) of MHO among these 7386 adults increased from 10.6% (8.8%-12.5%) in the 1999-2002 cycles to 15.0% (12.4%-17.6%) in the 2015-2018 cycles (P = .02 for trend). Substantial increases in the proportion of MHO were observed for adults aged 60 years or older, men, non-Hispanic White individuals, and those with higher income, private insurance, or class I obesity. In addition, there were significant decreases in the age-standardized prevalence (95% CI) of elevated triglycerides (from 44.9% [40.9%-48.9%] to 29.0% [25.7%-32.4%]; P < .001 for trend) and reduced HDL-C (from 51.1% [47.6%-54.6%] to 39.6% [36.3%-43.0%]; P = .006 for trend). There was also a significant increase in elevated FPG (from 49.7% [95% CI, 46.3%-53.0%] to 58.0% [54.8%-61.3%]; P < .001 for trend) but no significant change in elevated blood pressure (from 57.3% [53.9%-60.7%] to 54.0% [50.9%-57.1%]; P = .28 for trend). Conclusions and Relevance: The findings of this cross-sectional study suggest that the age-standardized proportion of MHO increased among US adults from 1999 to 2018, but differences in trends existed across sociodemographic subgroups. Effective strategies are needed to improve metabolic health status and prevent obesity-related complications in adults with obesity.
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Obesidade Metabolicamente Benigna , Masculino , Adulto , Humanos , Feminino , Obesidade Metabolicamente Benigna/epidemiologia , Inquéritos Nutricionais , Estudos Transversais , Prevalência , Obesidade/epidemiologia , TriglicerídeosRESUMO
Most land plant species have the ability to establish a symbiosis with arbuscular mycorrhizal (AM) fungi. These fungi penetrate into root cortical cells and form branched structures (known as arbuscules) for nutrient exchange. We cloned the MdIAA24 from apple (Malus domestica) following its up-regulation during AM symbiosis. Results demonstrate the positive impact of the overexpression (OE) of MdIAA24 in apple on AM colonization. We observed the strigolactone (SL) synthesis genes, including MdD27, MdCCD7, MdCCD8a, MdCCD8b and MdMAXa, to be up-regulated in the OE lines. Thus, the OE lines exhibited both a higher SL content and colonization rate. Furthermore, we observed that the OE lines were able to maintain better growth parameters under AM inoculation conditions. Under drought stress with the AM inoculation, the OE lines were less damaged, which was demonstrated by a higher relative water content, a lower relative electrolytic leakage, a greater osmotic adjustment, a higher reactive oxygen species scavenging ability, an improved gas exchange capacity and an increased chlorophyll fluorescence performance. Our findings demonstrate that the OE of MdIAA24 in apple positively regulates the synthesis of SL and the formation of arbuscules as a drought stress coping mechanism.
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Malus , Micorrizas , Secas , Compostos Heterocíclicos com 3 Anéis , Lactonas , Raízes de Plantas , Estresse Fisiológico , SimbioseRESUMO
Drought leads to reductions in plant growth and crop yields. Arbuscular mycorrhizal fungi (AMF), which form symbioses with the roots of the most important crop species, alleviate drought stress in plants. In the present work, we identified 14 GH3 genes in apple (Malus domestica) and provided evidence that MdGH3-2 and MdGH3-12 play important roles during AM symbiosis. The expression of both MdGH3-2 and MdGH3-12 was upregulated during mycorrhization, and the silencing of MdGH3-2/12 had a negative impact on AM colonization. MdGH3-2/12 silencing resulted in the downregulation of five genes involved in strigolactone synthesis, and there was a corresponding change in root strigolactone content. Furthermore, we observed lower root dry weights in RNAi lines under AM inoculation conditions. Mycorrhizal transgenic plants showed greater sensitivity to drought stress than WT, as indicated by their higher relative electrolytic leakage and lower relative water contents, osmotic adjustment ability, ROS scavenging ability, photosynthetic capacity, chlorophyll fluorescence values, and abscisic acid contents. Taken together, these data demonstrate that MdGH3-2/12 plays an important role in AM symbiosis and drought stress tolerance in apple.
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Arbuscular mycorrhizal fungi (AMF) can form a symbiotic relationship with most terrestrial plant roots, promote plant growth, and heavy metal (HM) tolerance and thus plays a crucial role in phytoremediation. However, research on the relationship between colonization level and HM tolerance is limited. In this study, apple (Malus domestica) Gretchen Hagen3 genes MdGH3-2/12 silencing plants were treated with four AMF and Cd combination treatments to determine AMF colonization levels, biomass, Cd accumulation, photosynthesis, fluorescence, reactive oxygen species (ROS) and antioxidant substance accumulation, and Cd uptake, transport and detoxification gene expression levels. Results indicate the greater sensitivity of transgenic plants under AMF inoculation and Cd treatment compared with wild type (WT) via lower AMF colonization levels, biomass accumulation, photosynthetic parameters, and the accumulation and clearance homeostasis of ROS, as well as lower detoxification expression levels and higher Cd uptake and transport expression levels. Our study essentially demonstrates that MdGH3-2/12 plays an important role in Cd stress tolerance by regulating AM colonization in apple.
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Malus , Micorrizas , Cádmio/toxicidade , Malus/genética , Raízes de Plantas , SimbioseRESUMO
Arbuscular mycorrhizal fungi (AMF) can form a symbiotic relationships with most terrestrial plants and play an important role in plant growth and adaptation to various stresses. To study the role of AMF in regulating drought resistance in apple, the effects of drought stress on Malus hupehensis inoculated with AMF were investigated. Inoculation of AMF enhanced apple plants growth. Mycorrhizal plants had higher total chlorophyll concentrations but lower relative electrolyte leakage under drought stress. Mycorrhizal plants increased net photosynthetic rate, stomatal conductance, and transpiration rate under drought stress, however, they showed lower inhibition in the quantum yield of PSII photochemistry. Mycorrhizal plants also had higher superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) enzyme activities under drought conditions. Thus, mycorrhizal plants had lower accumulated MDA, H2O2, and O2- than non-mycorrhizal seedlings. Total sugar and proline concentrations also significantly increased, helping maintain the osmotic balance. Furthermore, mitogen-activated protein kinase (MAPK) cascades, which participate in the regulation of responses of plants and microorganisms to biotic and abiotic stress, were up-regulated in apple plants and AMF during drought. We saw that there were at least two motifs that were identical in MAPK proteins and many elements that responded to hormones and stress from these MAPK genes. In summary, our results showed that mycorrhizal colonization enhanced apple drought tolerance by improving gas exchange capacity, increasing chlorophyll fluorescence parameters, creating a greater osmotic adjustment capacity, increasing scavenging of reactive oxygen species (ROS), and using MAPK signals for interactions between AMF and their apple plant hosts.
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Secas , Regulação da Expressão Gênica de Plantas , Malus , Proteínas Quinases Ativadas por Mitógeno , Micorrizas , Estresse Fisiológico , Malus/enzimologia , Malus/genética , Malus/microbiologia , Proteínas Quinases Ativadas por Mitógeno/genética , Micorrizas/fisiologia , Estresse Fisiológico/genéticaRESUMO
Follicular atresia is an inevitable degenerative process that occurs in mammalian ovarian follicles. The molecular events involved in atresia, particularly granulosa cell apoptosis, have long attracted researchers' attention. Vascular endothelial growth factor A (VEGFA) is downregulated during follicular atresia in porcine ovaries and serves as an inhibitor of apoptosis in granulosa cells. In addition, transforming growth factor (TGF)-ßsignaling has been considered a central trigger in granulosa cell apoptosis. However, the link between TGF-ß signaling and VEGFA is unknown. We proved that miR-361-5p is significantly upregulated during the atresia process and that it promotes GC apoptosis by directly targeting the VEGFA 3'UTR. In addition, we revealed that the miR-361-5p coding gene MIR361 was significantly downregulated by SMAD4, the central intracellular mediator of TGF-ß signaling, that bound to the MIR361 promoter. In conclusion, our findings expanded what is known about VEGFA posttranscriptional regulation and revealed a complete SMAD4/miR-361-5p/VEGFA regulatory network in ovarian granulosa cell apoptosis. These data provide useful references for follicular atresia and ovarian physiological function studies.
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Apoptose/genética , Células da Granulosa/metabolismo , MicroRNAs/metabolismo , Proteína Smad4/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Regiões 3' não Traduzidas , Animais , Regulação para Baixo , Feminino , Atresia Folicular/genética , Atresia Folicular/metabolismo , Regulação da Expressão Gênica , Células da Granulosa/citologia , Folículo Ovariano/metabolismo , Folículo Ovariano/patologia , Cultura Primária de Células , Regiões Promotoras Genéticas , Transdução de Sinais , Suínos , Regulação para CimaRESUMO
SiO2 nanowire arrays have been prepared by a template-assisted sol gel method and used as a negative electrode material for lithium ion batteries. Amorphous SiO2 was confirmed by X-ray diffraction and Fourier transform infrared spectroscopy. The results of scanning electron microscopy and transmission electron microscopy confirmed that the SiO2 nanowire had a diameter of about 100 nm and a length of about 30 µm. Cyclic voltammetry and constant current charge and discharge tests showed the prepared SiO2 nanowire arrays were electrochemically active at a potential range of 0.05-3.0 V. At a current density of 200 mA g-1, the first discharge specific capacity was as high as 2252.6 mA h g-1 with a coulombic efficiency of 60.7%. Even after about 400 cycles, it still maintained 97.5% of the initial specific capacity. Moreover, a high specific capacity of 315 mA h g-1 was exhibited when the current density was increased to 2500 mA g-1. SiO2 nanowire array electrodes with high reversible capacity and good cycle performance provide potential anode materials for future lithium-ion batteries.
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A novel electrochemiluminescent (ECL) signal tag of Au nanoparticles capped by 3,4,9,10-perylene tetracarboxylic acid-thiosemicarbazide functionalized C60 nanocomposites (AuNPs/TSC-PTC/C60NPs) was developed for thrombin (TB) aptasensor construction based on the peroxydisulfate/oxygen (S2O8(2-)/O2) system. For signal tag fabrication, the C60 nanoparticles (C60NPs) were prepared and then coated with 3,4,9,10-perylene tetracarboxylic acid (PTCA) by π-π stacking interactions. Afterwards, thiosemicarbazide (TSC) was linked with PTCA functionalized C60NPs via amidation for further assembling Au nanoparticles (AuNPs). Finally, detection aptamer of thrombin (TBA 2) was labeled on the ECL signal amplification tag of AuNPs/TSC-PTC/C60NPs. Herein, TSC, with the active groups of -NH2 and -SH, was selected and introduced into the ECL S2O8(2-)/O2 system for the first time, which could not only offer the active groups of -SH to absorb AuNPs for TBA 2 anchoring but also remarkably enhance the ECL signal of the S2O8(2-)/O2 system by the formation of TSC-PTC/C60NPs for signal amplification. Meanwhile, the sensing interface of a glassy carbon electrode (GCE) was modified by AuNPs/graphene (AuNPs/GR) nanocomposites with the large specific surface area and the active sites, followed by immobilization of thiol-terminated thrombin capture aptamer (TBA 1). With the formation of the sandwich-type structure of TBA 1, TB, and TBA 2 signal probes, a desirable enhanced ECL signal was measured in the testing buffer of an S2O8(2-)/O2 solution for detecting TB. The aptasensor exhibited a good linear relationship for TB detection in the range of 1 × 10(-5)-10 nM with a detection limit of 3.3 fM.
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In this work, a sandwich-type electrochemiluminescence (ECL) aptasensor for ultrasensitive detection of thrombin (TB) was designed based on mimicking bi-enzyme cascade catalysis to in situ generate coreactant of dissolved oxygen (O2) for signal amplification. We utilized hollow Au nanoparticles (HAuNPs) as carriers to immobilize glucose oxidase nanoparticles (GOxNPs) and Pt nanoparticles (PtNPs) by electrostatic adsorption. Then, the detection aptamer of thrombin (TBA 2) was immobilized on the PtNPs/GOxNPs/HAuNPs nanocomplexes. Finally, hemin was intercalated into the TBA 2 to obtain the hemin/G-quadruplex structure. The hemin/G-quadruplex was an interesting DNAzyme that commonly mimiced horseradish peroxidase (HRP). Herein, GOxNPs, hemin/G-quadruplex and PtNPs could form mimicking bi-enzyme cascade catalysis system to in situ generate dissolved O2 as coreactant in peroxydisulfate solution when the testing buffer contained proper amounts of glucose. This method had successfully overcome the disadvantage of difficulty to label the dissolved O2 and realized the ECL signal amplification. The experiment proved that the aptasensor had good linear relationship on low concentration of TB. The linear range was 1×10(-6)-10 nM, with a detection limit of 0.3 fM.
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Aptâmeros de Nucleotídeos/análise , Técnicas Biossensoriais/métodos , DNA Catalítico/metabolismo , Glucose Oxidase/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Nanopartículas/metabolismo , Trombina/análise , Adsorção , Aptâmeros de Nucleotídeos/metabolismo , Biocatálise , DNA Catalítico/química , Técnicas Eletroquímicas , Glucose Oxidase/química , Ouro/química , Ouro/metabolismo , Peroxidase do Rábano Silvestre/química , Luminescência , Mimetismo Molecular , Nanopartículas/química , Oxigênio/química , Oxigênio/metabolismo , Platina/química , Platina/metabolismo , Eletricidade Estática , Propriedades de Superfície , Trombina/metabolismoRESUMO
Titanium dioxide nanoparticles (TiO2 NPs) have the potential to produce reactive oxygen species and can be transferred from the mother to the fetal brain. The central nervous system exhibits remarkable plasticity in early life and can be altered significantly by environmental stressors encountered during fetal period. Additionally, prenatal stressors are involved with emotional problems in adulthood. The purpose of the current study is to evaluate whether prenatal exposure to TiO2 NPs could induce oxidative damage in the offspring brain and eventually affect the emotional behaviors in adulthood. The results showed that prenatal exposure to TiO2 NPs impaired the antioxidant status, caused a significant oxidative damage to nucleic acids and lipids in the brain of newborn pups, and enhanced the depressive-like behaviors during adulthood in the force swimming test and the sucrose preference test. These results suggest that the stress during fetal life induced by prenatal exposure to TiO2 NPs could be implicated in depressive-like behaviors in adulthood.