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1.
ScientificWorldJournal ; 2014: 528080, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24723812

RESUMO

The active appearance model (AAM) is one of the most powerful model-based object detecting and tracking methods which has been widely used in various situations. However, the high-dimensional texture representation causes very time-consuming computations, which makes the AAM difficult to apply to real-time systems. The emergence of modern graphics processing units (GPUs) that feature a many-core, fine-grained parallel architecture provides new and promising solutions to overcome the computational challenge. In this paper, we propose an efficient parallel implementation of the AAM fitting algorithm on GPUs. Our design idea is fine grain parallelism in which we distribute the texture data of the AAM, in pixels, to thousands of parallel GPU threads for processing, which makes the algorithm fit better into the GPU architecture. We implement our algorithm using the compute unified device architecture (CUDA) on the Nvidia's GTX 650 GPU, which has the latest Kepler architecture. To compare the performance of our algorithm with different data sizes, we built sixteen face AAM models of different dimensional textures. The experiment results show that our parallel AAM fitting algorithm can achieve real-time performance for videos even on very high-dimensional textures.


Assuntos
Algoritmos , Modelos Teóricos
2.
Sensors (Basel) ; 14(12): 24472-82, 2014 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-25536001

RESUMO

This work describes the fabrication, characterization, and application of a gold microband array electrode (MAE) for the determination of phosphate in fresh water samples. The working principle of this MAE is based on the reduction of a molybdophosphate complex using the linear sweep voltammetric (LSV) method. The calibration of this microsensor was performed with standard phosphate solutions prepared with KH2PO4 and pH adjusted to 1.0. The microsensor consists of a platinum counter electrode, a gold MAE as working electrode, and an Ag/AgCl electrode as reference electrode. The microelectrode chips were fabricated by the Micro Electro-Mechanical System (MEMS) technique. To improve the sensitivity, gold nanoparticles (AuNPs) were electrodeposited on the working electrode. With a linear range from 0.02 to 0.50 mg P/L, the sensitivity of the unmodified microsensor is 2.40 µA per (mg P/L) (R2 = 0.99) and that of the AuNPs-modified microsensor is 7.66 µA per (mg P/L) (R2 = 0.99). The experimental results showed that AuNPs-modified microelectrode had better sensitivity and a larger current response than the unmodified microelectrode.

3.
Sensors (Basel) ; 15(1): 382-93, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25549176

RESUMO

This paper investigated two different modification methods of graphene (GN) on ultramicroelectrode array (UMEA) and applied the GN modified UMEA for the determination of dissolved oxygen (DO). The UMEAs were fabricated by Micro Electro-Mechanical System (MEMS) technique and the radius of each ultramicroelectrode is 10 µm. GN-NH2 and GN-COOH were modified on UMEA by using self-assembling method. Compared with GN-NH2 modified UMEA, the GN-COOH modified UMEA showed better electrochemical reduction to DO, owing to better dispersing and more active sites. The GN-COOH on UMEA was electroreduced to reduced GN-COOH (rGN-COOH) to increase the conductivity and the catalysis performance. Finally, the palladium nanoparticles/rGN-COOH composite was incorporated into DO microsensor for the detection of DO.

4.
Mol Neurobiol ; 60(3): 1117-1131, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36417102

RESUMO

Intracerebral hemorrhage (ICH) is characterized by poor prognosis and high mortality rates. To date, satisfactory therapeutic approaches for ICH remain limited, so it is urgently needed to develop a safer and more effective prescription. Secondary inflammatory response has been acknowledged as an aggravating factor to neurological deterioration after ICH. As a component of inflammasome sensors, absent in melanoma 2 (AIM2) plays an important role in the neuroinflammation process. Here, ozanimod, a novel selective sphingosine 1-phosphate receptor modulator, has gained much attention, which alleviates the resultant neuroinflammation and improves functional recovery derived from ICH. In this study, ozanimod improved neurological functions of ICH mice via reduction of hematoma size. Furthermore, both microglial and AIM2 inflammasome activations were reversed by ozanimod, which are confirmed by the downregulation of related inflammatory proteins and cytokines (IL-1ß, IL-6, and TNF-α), coupled with the upregulation of SIRT3, by leveraging the Western blot and enzyme-linked immunosorbent assay. Additionally, we find that ozanimod decreases nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression. Notably, in vitro cell experiments induced by lipopolysaccharide confirms that the anti-inflammatory effect of ozanimod could be abolished by the SIRT3 inhibitor. In conclusion, these results indicate that ozanimod mitigates ICH-induced secondary inflammatory responses by modulating AIM2 inflammasome mediated by SIRT3/NF-κB/AIM2 pathway. This demonstrates ozanimod orchestrates ICH-induced neuroinflammation and could be a targeted therapy for improving prognosis of ICH.


Assuntos
NF-kappa B , Sirtuína 3 , Camundongos , Animais , NF-kappa B/metabolismo , Inflamassomos , Doenças Neuroinflamatórias , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/metabolismo , Proteínas de Ligação a DNA/metabolismo
5.
Biomed Microdevices ; 13(2): 345-52, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21170592

RESUMO

A field effect transistor (FET)-based immunosensor was developed for diabetes monitoring by detecting the concentrations of glycated hemoglobin (HbA1c) and hemoglobin (Hb). This immunosensor consists of a FET-based sensor chip and a disposable extended-gate electrode chip. The sensor chip was fabricated by standard CMOS process and was integrated with signal readout circuit. The disposable electrode chip, fabricated on polyester plastic board by Micro-Electro-Mechanical-Systems (MEMS) technique, was integrated with electrodes array and micro reaction pool. Biomolecules were immobilized on the electrode based on self-assembled monolayer and gold nanoparticles. Experimental results showed that the immunosensor achieved a linear response to HbA1c with the concentration from 4 to 24 µg/ml, and a linear response to Hb with the concentration from 60 to 180 µg/ml.


Assuntos
Técnicas Biossensoriais/instrumentação , Hemoglobinas Glicadas/análise , Imunoensaio/instrumentação , Transistores Eletrônicos , Animais , Anticorpos/imunologia , Bovinos , Espectroscopia Dielétrica , Equipamentos Descartáveis , Eletroquímica , Eletrodos , Hemoglobinas Glicadas/química , Hemoglobinas Glicadas/imunologia , Ouro/química , Proteínas Imobilizadas/química , Platina/química , Soroalbumina Bovina/química
6.
Cancer Manag Res ; 13: 5187-5201, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234562

RESUMO

OBJECTIVE: Tripartite motif 66 (TRIM66) is reported to be closely associated with human cancers. However, the roles of TRIM66 in glioma remain unclear. The present study aimed to investigate the clinical significance and biological roles of TRIM66 in human glioma. METHODS: TRIM66 expression in glioma tissues was examined by immunohistochemistry. TRIM66 overexpression and siRNA knockdown were performed in glioblastoma cell lines. CCK8, colony formation assay, transwell assay, Annexin V and JC1 staining, glucose uptake assay, and Western blotting were used to explore the biological roles and potential underlying mechanisms of TRIM66 in glioma progression. RESULTS: Our results showed that TRIM66 was overexpressed in 52/95 glioma cases. The rates of TRIM66 overexpression in Grade I, Grade II, Grade III, and Grade IV gliomas were 16.6%, 41.3%, 58.6%, and 70.9%, respectively. Oncomine data showed that TRIM66 was upregulated in glioblastoma and oligodendroglioma compared with normal brain tissues. TRIM66 expression was higher in glioblastoma cell lines compared with normal SVG p12 glial cell line. TRIM66 promoted in vitro and in vivo proliferation, invasion, and inhibited temozolomide (TMZ)-induced apoptosis. Notably, TRIM66 increased glucose metabolism by upregulating glucose uptake, glucose consumption, and ATP production. Western blotting showed that TRIM66 positively regulated cMyc and GLUT3. Depletion of cMyc by siRNA abolished the effect of TRIM66 on GLUT3. Chromatin immunoprecipitation (ChIP) assay showed that cMyc could bind to the promoter regions of GLUT3 in glioblastoma cells. CONCLUSION: TRIM66 was upregulated in human gliomas, where it promoted cell growth and chemoresistance. Our data also identified novel roles of TRIM66 in glioma progression. TRIM66 upregulates glucose uptake and mitochondrial function through the cMyc/GLUT3 signaling, which makes it a potential therapeutic target.

7.
Micromachines (Basel) ; 10(4)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934835

RESUMO

An ultramicro interdigital array electrode modified by palladium-gold was developed for nitrate detection in neutral water. The ultramicro interdigital array electrode was fabricated based on silicon substrate by Micro Electro-Mechanical System (MEMS) technique. The nanostructured palladium-gold (Pd-AuNPs) composite sensing film was electrodeposited on the surface of a working electrode by electrochemical method. The synergistic effect of Pd-AuNPs composite was investigated and its enhancement of the catalytic activity and stability was revealed. The Pd-AuNPs modified electrode showed good linearity (R² = 0.99) from 1 mg/L to 15 mg/L (as N) for nitrate determination in a neutral water environment (pH = 7.2), with a sensitivity of 4.7 µA·mg-1·L. The results showed that the developed Pd-AuNPs-modified ultramicro interdigital array electrode chip can achieve sensitive and environmentally-friendly detection for nitrate in neutral water.

8.
IEEE Trans Pattern Anal Mach Intell ; 41(12): 2791-2806, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31689178

RESUMO

This paper studies active relocalization of 6D camera pose from a single reference image, a new and challenging problem in computer vision and robotics. Straightforward active camera relocalization (ACR) is a tricky and expensive task that requires elaborate hand-eye calibration on precision robotic platforms. In this paper, we show that high-quality camera relocalization can be achieved in an active and much easier way. We propose a hand-eye calibration free approach to actively relocating the camera to the same 6D pose that produces the input reference image. We theoretically prove that, given bounded unknown hand-eye pose displacement, this approach is able to rapidly reduce both 3D relative rotational and translational pose between current camera and the reference one to an identical matrix and a zero vector, respectively. Based on these findings, we develop an effective ACR algorithm with fast convergence rate, reliable accuracy and robustness. Extensive experiments validate the effectiveness and feasibility of our approach on both laboratory tests and challenging real-world applications in fine-grained change monitoring of cultural heritages.

9.
Micromachines (Basel) ; 9(4)2018 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30424084

RESUMO

Heavy metal ion pollution problems have had a terrible influence on human health and the environment. Therefore, the monitoring of heavy metal ions is of great practical significance. In this paper, an electrochemical three-electrode system was fabricated and integrated on nitrocellulose membrane (NC) by the use of magnetron sputtering technology, which exhibited a uniform arrangement of porous structure without further film modification. This paper-based sensor chip was used for Cu2+ detection by square-wave stripping voltammetry (SWSV). Within the ranges of 5~200 µg·L-1 and 200~1000 µg·L-1, it showed good linearity of 99.58% and 98.87%, respectively. The limit of detection was 2 µg·L-1. On the basis of satisfying the detection requirements (10 µg·L-1), the integrated sensor was small in size and inexpensive in cost. Zn2+, Cd2+, Pb2+ and Bi3+ were also detected by this paper-based sensor chip with good linearity.

10.
Biosens Bioelectron ; 114: 15-21, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29775854

RESUMO

The study presented herein investigated an easy preparation, high performance, wavelength-modulated LSPR optical fiber chemosensor coated by gold nanospheres(AuNS) for Hg2+ detection based on thymine-Hg2+-thymine base pair mismatches and the coupled plasmonic resonance effect.Utilizing electrostatic self-assembly method, the high density and dispersivity monolayer AuNS coated LSPR fiber sensor had the near field refractive index sensitivity up to 2016 nm/RIU. The single-strand probe DNA served as a binding element for free AuNS labelled-target DNA conjugates was attached to the monolayer AuNS by Au-S bond. In the present of Hg2+, the coupled plasmonic resonance band between monolayer AuNS and free AuNS was produced by thymine-Hg2+-thymine structure and leaded to red-shift of LSPR peak. Under the optimal conditions, the enlarged red-shift in peak of LSPR spectroscopy was linearly with the concentration of Hg2+ in the range from 1.0 × 10-9 to 5.0 × 10-8 M with the coefficient of 0.976. The limit of detection was 0.7 nM(S/N = 3). The specificity of the sensor was proved high by evaluating the response to other heavy metal ions. The proposed fiber sensor provided a label-free, miniature, low-cost approach for the Hg2+ detection and had potential in real environmental evaluations.


Assuntos
Ouro/química , Mercúrio/análise , Nanopartículas Metálicas/química , Fibras Ópticas , Ressonância de Plasmônio de Superfície/métodos , Técnicas Biossensoriais/métodos , Cátions Bivalentes , Cor , DNA de Cadeia Simples/química , Limite de Detecção , Tamanho da Partícula , Ressonância de Plasmônio de Superfície/instrumentação , Propriedades de Superfície , Timina/química
11.
Biosens Bioelectron ; 80: 222-229, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26851579

RESUMO

Gold nanoparticles (AuNPs) embedded in chitosan (CHI) film, well-dispersed and smaller in size (about 10 nm), were fabricated by one-step electrodeposion on Au microelectrode in solution containing chitosan and chloride trihydrate. The nano-structure CHI-AuNPs composite film offers abundant amine groups, good conductivity, excellent biocompatibility and stability for antibody immobilization. The combination of aflatoxin B1 (AFB1) with immobilized antibody introduces a barrier to electron transfer, resulting in current decreasement. The morphologies and characterizations of modified microelectrodes were investigated by scanning electron microscope (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR). The proposed non-enzyme and label-free immunosensor exhibited high sensitive amperometric response to AFB1 concentration in two linear ranges of 0.1 to 1 ng mL(-1) and 1 to 30 ng mL(-1), with the detection limit of 0.06 ng mL(-1) (S/N=3). The immunoassay was also applied for analysis of maize samples spiked with AFB1. Considering the sample extraction procedure, the linear range and limit of detection were assessed to be 1.6-16 ng mL(-1) and 0.19 ng mL(-1) respectively. The simple method showed good fabrication controllability and reproducibility for immunosensor design.


Assuntos
Aflatoxina B1/isolamento & purificação , Técnicas Biossensoriais , Técnicas Eletroquímicas , Imunoensaio , Aflatoxina B1/química , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Materiais Biocompatíveis/química , Quitosana/química , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Microeletrodos , Nanotubos de Carbono/química , Zea mays/química
12.
PeerJ ; 4: e2342, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27602300

RESUMO

As the most widely distributed snake in Eurasia, the adder (Vipera berus) has been extensively investigated in Europe but poorly understood in Asia. The Southern Altay Mountains represent the adder's southern distribution limit in Central Asia, whereas its population status has never been assessed. We conducted, for the first time, field surveys for the adder at two areas of Southern Altay Mountains using a combination of line transects and random searches. We also described the morphological characteristics of the collected specimens and conducted analyses of external morphology and molecular phylogeny. The results showed that the adder distributed in both survey sites and we recorded a total of 34 sightings. In Kanas river valley, the estimated encounter rate over a total of 137 km transects was 0.15 ± 0.05 sightings/km. The occurrence of melanism was only 17%. The small size was typical for the adders in Southern Altay Mountains in contrast to other geographic populations of the nominate subspecies. A phylogenetic tree obtained by Bayesian Inference based on DNA sequences of the mitochondrial cytochrome b (1,023 bp) grouped them within the Northern clade of the species but failed to separate them from the subspecies V. b. sachalinensis. Our discovery extends the distribution range of V. berus and provides a basis for further researches. We discuss the hypothesis that the adder expands its distribution border to the southwest along the mountains' elevation gradient, but the population abundance declines gradually due to a drying climate.

13.
Mol Med Rep ; 13(5): 4357-64, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27052602

RESUMO

Chemotactic cytokines (chemokines) are a highly conserved class of secreted signaling molecules that are important in various cellular processes. CXC chemokine ligand 12 (CXCL12) and its receptor, CXC chemokine receptor 4 (CXCR4) have been previously reported to be crucial for the establishment of neural networks in different neuronal systems. However, it is unclear whether the CXCL12/CXCR4 signaling pathway regulates the development of the cochlea. The current study investigated the effects of the CXCL12/CXCR4 signaling pathway on cochlear development in neonatal mice. The expression levels of CXCL12 and CXCR4 were detected using immunofluorescence, reverse transcription­quantitative polymerase chain reaction and western blot analysis demonstrating that CXCL12 and CXCR4 expression were significantly increased during cochlear development in neonatal mice. Treatment of spiral ganglion neurons with CXCL12 significantly decreased the protein expression levels of caspase­3 and cleaved caspase­3, indicating that CXCL12/CXCR4 signaling increased cell survival of spiral ganglion neurons. Furthermore, CXCL12 treatment significantly increased the number and length of neurites extending from spiral ganglion neurons. By contrast, the in vitro effects of CXCL12 were significantly abrogated by AMD100, a CXCR4 antagonist. Additionally, inhibiting CXCL12/CXCR4 signaling in neonatal mice significantly reduced the cell number and altered the morphology of spiral ganglion neurons in vivo. Thus, the present study indicates that the CXCL12/CXCR4 signaling pathway is important during the development of cochleae in neonatal mice.


Assuntos
Quimiocina CXCL12/biossíntese , Regulação da Expressão Gênica/fisiologia , Neuritos/metabolismo , Receptores CXCR4/biossíntese , Transdução de Sinais/fisiologia , Gânglio Espiral da Cóclea/crescimento & desenvolvimento , Animais , Caspase 3/biossíntese , Camundongos , Gânglio Espiral da Cóclea/citologia
14.
Sci Rep ; 5: 14371, 2015 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-26394926

RESUMO

Although a significant amount of work has been performed to preserve the ancient murals in the Mogao Grottoes by Dunhuang Cultural Research, non-contact methods need to be developed to effectively evaluate the degree of flaking of the murals. In this study, we propose to evaluate the flaking by automatically analyzing hyperspectral images that were scanned at the site. Murals with various degrees of flaking were scanned in the 126th cave using a near-infrared (NIR) hyperspectral camera with a spectral range of approximately 900 to 1700 nm. The regions of interest (ROIs) of the murals were manually labeled and grouped into four levels: normal, slight, moderate, and severe. The average spectral data from each ROI and its group label were used to train our classification model. To predict the degree of flaking, we adopted four algorithms: deep belief networks (DBNs), partial least squares regression (PLSR), principal component analysis with a support vector machine (PCA + SVM) and principal component analysis with an artificial neural network (PCA + ANN). The experimental results show the effectiveness of our method. In particular, better results are obtained using DBNs when the training data contain a significant amount of striping noise.

15.
Biosens Bioelectron ; 26(5): 2689-93, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20947325

RESUMO

A micro potentiometric immunosensor based on mixed SAMs wrapped nano-spheres array for the detection of hemoglobin-A1c level is presented in this paper. Nano-spheres array is prepared by wrapping nano-gold particle with mixed SAMs on the surface of micro immunosensor. Mixed SAMs make the nano-gold particles distribute uniformly without aggregation and render the signal less susceptible to noise. Based on this nano-spheres array, antibody is covalently immobilized on the immunosensor surface. The micro immunosensor, consisting of ISFET integrated chip and MEMS electrodes array is applied to measure hemoglobin-A1c level by detecting the concentration of hemoglobin-A1c and hemoglobin simultaneously. The responses of the immunosensor are linear over the concentration range of 166.7-570 ng/ml hemoglobin and 50-170.5 ng/ml HbA1c. Whole blood sample obtained from hospital was also examined using this immunosensor. The low relative deviation shows that this micro immunosensor may provide an alternative tool for the determination of HbA1c level.


Assuntos
Técnicas Biossensoriais/instrumentação , Análise Química do Sangue/instrumentação , Condutometria/instrumentação , Hemoglobinas Glicadas/análise , Imunoensaio/instrumentação , Nanosferas/química , Misturas Complexas/sangue , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Miniaturização , Transistores Eletrônicos
16.
Biosens Bioelectron ; 24(12): 3419-24, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19110412

RESUMO

We report a novel micro-potentiometric hemoglobin (Hb) immunosensor based on electrochemically synthesized polypyrrole (PPy)-gold nanoparticles (AuNPs) composite. PPy-AuNPs film with AuNPs uniformly distributed in it was deposited on gold electrode surface by a simple and direct procedure, without the addition of any nanoparticles or reducing agent. And this generic method makes it possible to deposite different polymers on miniaturized electrodes. With the existence of AuNPs, the antibody immobilization onto the electrode surface was facilitated. Morphology study by field emission scanning electron microscope (FE-SEM) confirms the presence of AuNPs in PPy. Based on an ion-sensitive field-effect transistors (ISFETs) integrated chip, a micro-potentiometric immunosensor for Hb and hemoglobin-A1c (HbA1c) has been constructed. The sensor response was linear over the concentration range 60-180 microg/ml Hb and 4-18 microg/ml HbA1c. The Hb concentration in whole blood samples has also been analysed, with a linear dose-response behavior between 125 and 197 microg/ml and a sensitivity of 0.20 mV microg(-1)ml. The measuring ranges of the developed Hb and HbA1c immunosensors meet the clinical demand for measuring the HbA1c/Hb ratio of 5-20%. This sensor results in simple and rapid differential measurement of Hb and HbA1c, and has great potential to become an inexpensive and portable device for monitoring of diabetes.


Assuntos
Eletroquímica/instrumentação , Ouro/química , Hemoglobinas/análise , Imunoensaio/instrumentação , Nanopartículas/química , Nanotecnologia/instrumentação , Polímeros/química , Pirróis/química , Técnicas Biossensoriais , Desenho de Equipamento , Análise de Falha de Equipamento , Hemoglobinas/imunologia , Microeletrodos , Miniaturização , Nanopartículas/ultraestrutura , Tamanho da Partícula , Transistores Eletrônicos
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