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1.
Sensors (Basel) ; 19(11)2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31195702

RESUMO

Wireless Sensor Networks (WSNs) had been applied in Internet of Things (IoT) and in Industry 4.0. Since a WSN system contains multiple wireless sensor nodes, it is necessary to develop a low-power and multiband wireless communication system that satisfies the specifications of the Federal Communications Commission (FCC) and the Certification European (CE). In a WSN system, many devices are of very small size and can be slipped into a Universal Serial Bus (USB), which is capable of connecting to wireless systems and networks, as well as transferring data. These devices are widely known as USB dongles. This paper develops a planar USB dongle antenna for three frequency bands, namely 2.30-2.69 GHz, 3.40-3.70 GHz, and 5.15-5.85 GHz. This study proposes a novel antenna design that uses four loops to develop the multiband USB dongle. The first and second loops construct the low and intermediate frequency ranges. The third loop resonates the high frequency property, while the fourth loop is used to enhance the bandwidth. The performance and power consumption of the proposed multiband planar USB dongle antenna were significantly improved compared to existing multiband designs.

2.
Mol Biol Rep ; 38(6): 4193-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21110107

RESUMO

Lipopolysaccharide (LPS) from gram negative bacteria plays an important role in the pathophysiology of neurodegenerative diseases. Many evidences showed that LPS-induced neuroinflammation is related to upregulation of NF-kappaB. Here, we report that long-term treatment of lower dosage LPS mainly causes upregulation of Id2 protein. As an inhibitor of cell differentiation, Id2 plays an import role in adult olfactory neurogenesis. However, Id2 protein in brain acts as two edges in a sword, persist over-expression of Id2 in brain can induce neurodamages and may be related to neurodegeneration.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Proteína 2 Inibidora de Diferenciação/metabolismo , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/farmacologia , Animais , Benzimidazóis/metabolismo , Western Blotting , Encéfalo/patologia , Morte Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína 2 Inibidora de Diferenciação/genética , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos C57BL , Propídio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
3.
Cell Biochem Funct ; 27(4): 238-42, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19384903

RESUMO

The translocations of lipopolysaccharide (LPS) from the gut and its effects on bone healing are usually of clinical interest during bone fracture. As already widely studied, Cyclooxygenase-2 (COX-2) is a key enzyme for prostaglandin E2 (PGE(2)) production, which induces the nuclear factor kappa B (NFkappaB) activation and is beneficial to fracture healing. In order to know their roles in skeletal regeneration, mouse MC3T3-E1 osteoblasts were treated with NFkappaB inhibitor BAY 11-7082 and sc791 (a selective COX-2 inhibitor), in the presence of LPS. Interestingly, LPS could induce osteoblasts proliferation through increasing NFkappaB activation and translocation. This induction was not related to COX-2 expression, suggesting that LPS-induced NFkappaB activation is independent of COX-2. It is possible that low concentration of LPS can act as a stimulating factor of the NFkappaB pathway in nonstimulated cells such as osteoblasts. COX-2 is not necessary for the NFkappaB pathway during LPS-induced proliferation of osteoblasts since sc791 had no effects on this induction. These studies provide insight into a potential mechanism by which LPS can affect bone tissue repair in the initial phase of inflammation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Osteoblastos/efeitos dos fármacos , Animais , Linhagem Celular , Camundongos , NF-kappa B/antagonistas & inibidores , Nitrilas/farmacologia , Osteoblastos/metabolismo , Transdução de Sinais , Sulfonas/farmacologia
4.
Cell Biochem Funct ; 26(5): 598-602, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18508388

RESUMO

The mitochondrial flavoprotein apoptosis-inducing factor (AIF) has proved to be either the main mediator of apoptosis or an anti-apoptotic factor via its putative oxidoreductase and peroxide scavenging activities. We report here that 100 muM hydrogen peroxide (H2O2) induced the proliferation of C2C12 myoblasts and over-expression of AIF simultaneously in vitro. Immunofluorescence showed that the over-expression of AIF was located in the cytoplasm. The immunopositive AIF was detected in nuclei 27 days after denervation of skeletal muscle, but in the cytoplasm it was detected 27 days after fiber-damaged skeletal muscle. AIF may be a factor involved in skeletal muscle regeneration.


Assuntos
Fator de Indução de Apoptose/fisiologia , Proteínas Mitocondriais/fisiologia , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/fisiologia , Regeneração/fisiologia , Animais , Fator de Indução de Apoptose/biossíntese , Fator de Indução de Apoptose/genética , Linhagem Celular , Peróxido de Hidrogênio/metabolismo , Masculino , Camundongos , Proteínas Mitocondriais/biossíntese , Proteínas Mitocondriais/genética , Ratos , Ratos Sprague-Dawley
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(7): 1095-8, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16241064

RESUMO

Cuprum-enriched cuprum sulfide nanoparticles (CuS/Cu2+) were prepared. The nanoparticles are water-soluble. They could be used as a resonance light scattering (RLS) probe in the determination of human gamma globulin, which was proved to be a simple, rapid and specific method. In comparison with organic dye probes, these nanoparticles probes are brighter, more stable against photobleaching, and do not suffer from blinking. Under optimum conditions, the response is linearly proportional to the concentration of gamma globulin between 0.1 and 1.5 mg x L(-1), and the detection limit is 0.064 6 mg x L(-1).


Assuntos
Cobre/química , Nanopartículas/química , gama-Globulinas/análise , Humanos , Concentração de Íons de Hidrogênio , Luz , Microscopia Eletrônica de Transmissão , Sondas Moleculares/química , Nanopartículas/ultraestrutura , Espalhamento de Radiação , Espectrometria de Fluorescência , gama-Globulinas/química , gama-Globulinas/ultraestrutura
6.
Anal Bioanal Chem ; 382(5): 1300-3, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15915346

RESUMO

Organic fluorescence nanoparticles (1-aminopyrene nanoparticles) were prepared under ultrasonic radiation and used to determine nitrite. Such nanoparticles have a broad, continuous excitation spectrum, but they are also photochemically stable and water-soluble. Nitrite determination was based upon nitrite quenching the fluorescence of the nanoparticles due to a simple diazotization reaction; a simple and specific method. Under optimal conditions, the linear range of the calibration curve was 20-1400 ng ml(-1), with a correlation coefficient of 0.9987 for nitrite. The detection limit was 3 ng ml(-1). The method was applied to various water samples from several sources. Quantitative nitrite recoveries and satisfactory results were achieved.


Assuntos
Nanopartículas , Nitritos/análise , Pirenos/química , Poluentes Químicos da Água/análise , Água/análise , Calibragem , Solubilidade , Espectrometria de Fluorescência
7.
J Zhejiang Univ Sci ; 5(1): 92-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14663859

RESUMO

The current standard Unified Modeling Language(UML) could not model framework flexibility and extendability adequately due to lack of appropriate constructs to distinguish framework hot-spots from kernel elements. A new UML profile that may customize UML for framework modeling was presented using the extension mechanisms of UML, providing a group of UML extensions to meet the needs of framework modeling. In this profile, the extended class diagrams and sequence diagrams were defined to straightforwardly identify the hot-spots and describe their instantiation restrictions. A transformation model based on design patterns was also put forward, such that the profile based framework design diagrams could be automatically mapped to the corresponding implementation diagrams. It was proved that the presented profile makes framework modeling more straightforwardly and therefore easier to understand and instantiate.


Assuntos
Algoritmos , Sistemas de Gerenciamento de Base de Dados , Bases de Dados Factuais , Armazenamento e Recuperação da Informação/métodos , Modelos Teóricos , Linguagens de Programação , Design de Software , Simulação por Computador , Software , Validação de Programas de Computador
8.
J Zhejiang Univ Sci ; 5(1): 99-105, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14663860

RESUMO

This novel method of Pedestrian Tracking using Support Vector (PTSV) proposed for a video surveillance instrument combines the Support Vector Machine (SVM) classifier into an optic-flow based tracker. The traditional method using optical flow tracks objects by minimizing an intensity difference function between successive frames, while PTSV tracks objects by maximizing the SVM classification score. As the SVM classifier for object and non-object is pre-trained, there is need only to classify an image block as object or non-object without having to compare the pixel region of the tracked object in the previous frame. To account for large motions between successive frames we build pyramids from the support vectors and use a coarse-to-fine scan in the classification stage. To accelerate the training of SVM, a Sequential Minimal Optimization Method (SMO) is adopted. The results of using a kernel-PTSV for pedestrian tracking from real time video are shown at the end. Comparative experimental results showed that PTSV improves the reliability of tracking compared to that of traditional tracking method using optical flow.


Assuntos
Algoritmos , Inteligência Artificial , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão , Fotografação/métodos , Gravação em Vídeo/métodos , Caminhada/fisiologia , Simulação por Computador , Metodologias Computacionais , Humanos , Sistemas On-Line , Técnica de Subtração
9.
Talanta ; 62(2): 237-40, 2004 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-18969286

RESUMO

A novel assay of gamma-globulin (gamma-IgG) with a sensitivity at the nanogram level is proposed based on the measurement of enhanced resonance light-scattering (RLS) signals resulting from the interaction of functionalized nano-HgS with gamma-globulin. At pH 5.03, the RLS signals of functionalized nano-HgS were greatly enhanced by gamma-globulin in the region of 200-700nm characterized by the peak around 362nm. Linear relationship can be established between the enhanced RLS intensity and gamma-globulin concentration in the range of 10-140ngml(-1). The limit of detection is 2.71ngml(-1). Based on this, a new direct quantitative determination method for gamma-globulin in blood serum samples without separation of human serum albumin (HSA) is established. The contents of gamma-IgG in blood serum samples were determined with recovery of 95.7-102.5% and R.S.D. of 1.6-2.4%. This method is proved to be very sensitive, rapid, simple and tolerance of most interfering substances.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(1): 98-101, 2004 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15768988

RESUMO

In this work, nano-ZnS has been successfully prepared. The nano-ZnS has also been modified with sodium mercaptoacetic acid. The functionalized nanoparticles are water-soluble and biocompatible. All the nanoparticles have been characterized by IR spectra, UV spectra, fluorescence spectra and TEM images. In comparison with single organic fluorophore, the nanoparticles probes are brighter and more photostable, and do not suffer from blinking. The nanoparticles have a narrow, tunable, symmetric emission spectrum and a broad, continuous excitation spectrum. They are also photochemically stable. Effects of proteins and nucleic acids on the UV spectra and fluorescence spectra of the functionalized ZnS have also been studied. The intensities of UV spectra and fluorescence spectra of the functionalized ZnS are enhanced by proteins, and, however, are quenched by nucleic acids. The functionalized colloidal solutions prepared are hopeful of use as fluorescence probes in biological staining and diagnostics.


Assuntos
Nanopartículas/química , Nanotecnologia/métodos , Espectrometria de Fluorescência/métodos , Sulfetos/química , Compostos de Zinco/química , Fluorescência , Corantes Fluorescentes , Nanoestruturas , Sulfetos/síntese química , Compostos de Zinco/síntese química
11.
Anal Bioanal Chem ; 378(3): 811-5, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14647943

RESUMO

Nanometer-sized L-cysteine-capped ZnS particles have been synthesized and used as a fluorescence probe to investigate the effect of proteins on fluorescent intensity. With Delta lambda=190 nm, maximum and constant synchronous fluorescence enhancement was produced at 267 nm and pH 5.12 in the presence of proteins. A highly sensitive synchronous fluorescence method for the rapid determination of proteins has been developed. Under optimum conditions, calibration graphs are linear over the range 0.03-8.0 microg mL(-1) for bovine serum albumin (BSA), 0.01-6.0 microg mL(-1) for human serum albumin (HSA), 0.05-8.0 microg mL(-1) for gamma-globulin (gamma-G), and 0.04-4.0 microg mL(-1) for ovalbumin, respectively. The relative standard deviations of seven replicate measurements were 1.75% for 1.0 microg mL(-1) BSA, 1.90% for 1.0 microg mL(-1) HSA, 1.65% for 1.0 microg mL(-1) gamma-G, and 2.32% for 1.0 microg mL(-1) ovalbumin.


Assuntos
Cisteína/química , Corantes Fluorescentes/química , Proteínas/análise , Sulfetos/química , Compostos de Zinco/química , Calibragem , Microscopia Eletrônica , Nanotecnologia
12.
Analyst ; 127(11): 1531-4, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12475047

RESUMO

ZnS nanoparticles have been prepared and modified with sodium thioglycolate. The functionalized nanoparticles are water-soluble. They were used as fluorescence probes in the determination of proteins, which was proved to be a simple, rapid and specific method. In comparison with single organic fluorophores, these nanoparticle probes are brighter, more stable against photobleaching, and do not suffer from blinking. Under optimum conditions, linear relationships were found between the enhanced intensity of fluorescence at 441 nm and the concentration of protein in the range 0.1-4.0 microg mL(-1) for human serum albumin (HSA), 0.2-3.0 microg mL(-1) for bovine serum albumin (BSA) and 0.1-4.5 microg mL(-1) for gamma-globulin (gamma-G). The limits of detection were 0.015 microg mL(-1) for HSA, 0.024 microg mL(-1) and 0.017 microg mL(-1) for BSA and gamma-G, respectively. The method has been applied to the analysis of human serum samples collected from the hospital and the results were in good agreement with those reported by a hospital, indicating that the method presented here is not only sensitive and simple, but also reliable and suitable for practical application.


Assuntos
Proteínas/análise , Coloides , Microscopia de Fluorescência/instrumentação , Microscopia de Fluorescência/métodos , Nanotecnologia/métodos , Sulfetos , Compostos de Zinco
13.
Analyst ; 127(7): 977-80, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12173661

RESUMO

Nanometer-sized fluorescent particles were successfully synthesized. The nanoparticles have a narrow, tunable, symmetric emission spectrum and a broad, continuous excitation spectrum. They are also photochemically stable. A synchronous fluorescence method was developed for the rapid determination of DNA with functionalized CdS as a fluorescence probe, based on the synchronous fluorescence quenching of functionalized CdS in the presence of DNA. Maximum fluorescence is produced at pH 7.0, with maximum excitation and emission wavelengths of 360 and 620 nm, respectively. The maximum emission wavelength of synchronous fluorescence is 354 nm when delta lambda = 260 nm. Under optimum conditions, the calibration graphs are linear over the range 0-3.5 microg mL(-1) for calf thymus DNA (CT-DNA) and 0.2-3.0 microg mL(-1) for fish sperm DNA. The corresponding detection limit is 0.01 microg mL(-1) for CT-DNA and 0.02 microg mL(-1) for fish sperm DNA. The relative standard deviation of seven replicate measurements is 2.2% for 1 microg mL(-1) calf thymus DNA and 2.4% for 1 microg mL(-1) fish sperm DNA. The method is simple, rapid and sensitive. The recovery and relative standard deviation are very satisfactory.


Assuntos
DNA/análise , Animais , Compostos de Cádmio , Bovinos , Coloides , Corantes Fluorescentes , Microscopia Eletrônica , Nanotecnologia , Espectrometria de Fluorescência , Sulfetos
14.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 22(3): 196-9, 2002 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12585106

RESUMO

OBJECTIVE: To explore the effect of Xiaolong Tongbi (XLTB), a Chinese herbal preparation, on nitric oxide synthase (NOS) containing nerve and epithelial cell apoptosis. METHODS: NOS containing nerve level of various groups prostate was determined by NADPH histochemical staining and morphological quantitative analysis, and the cell apoptosis rate in rats prostatic epithelium was tested immunohistochemically with TUNEL method. RESULTS: After 3 weeks treatment with high dose XLTB, the length density of NOS contained nerves in prostate tissue of rats was 0.113 +/- 0.023, which was significantly different to that in the other 3 groups (low dose XLTB, Finasteride and testosterone) respectively (P < 0.01). Cell apoptosis reached its peak at the day 7 of experiment in XLTB treated groups (9.27%), and Finasteride treated group (5.65%), which lowered slightly at day 14 and got some recovery at day 21. Castration induced cell apoptosis began at day 7 and reached its peak at day 14, which was significantly different from that in the other groups. CONCLUSION: XLTB could increase the NOS contained nerve level and accelerate the apoptosis of epithelial cell in prostate tissue of simulating benign prostatic hyperplasia rats.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/citologia , Óxido Nítrico Sintase/metabolismo , Próstata/enzimologia , Animais , Masculino , Músculo Liso/enzimologia , Óxido Nítrico Sintase Tipo III , Próstata/patologia , Distribuição Aleatória , Ratos , Ratos Wistar
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