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1.
Mol Ther Nucleic Acids ; 16: 63-72, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-30849743

RESUMO

We previously found that lung tumor development was reduced in a presenilin (PS) Alzheimer's disease (AD) mouse model. Here, we investigated whether this reducing effect could occur in a different AD mouse model. We investigated urethane-induced (1 mg/g) lung tumor development and melanoma growth in Swedish amyloid precursor protein (SwAPP) transgenic mice. The expression of chitinase-3-like-1 (Chi3L1) increased during lung tumor development and melanoma growth, which was accompanied by an increase in the activity of signal transducer and activator of transcription 3 (STAT3) and the downregulation of miRNA342-3p in wild-type mice. Like tumor development, the expression of Chi3L1 and STAT3 activity was reduced in the SwAPP mice, whereas the expression of miRNA342-3p was upregulated. In addition, Chi3L1 knockdown in the lung cancer and melanoma tissues reduced cancer cell growth and STAT3 activity but enhanced miRNA342-3p expression. However, the miRNA342-3p mimic decreased Chi3L1 expression, cancer cell growth, and STAT3 activity. Moreover, a STAT3 inhibitor reduced Chi3L1 expression and cancer cell growth but enhanced miRNA342-3p expression. These data showed that lung tumor development was reduced through the decrease of Chi3L1 expression via the STAT3-dependent upregulation of miRNA342-3p. This study indicates that lung tumor development could be reduced in SwAPP AD mice.

2.
Brain Behav Immun ; 53: 113-122, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26593275

RESUMO

Nearly 7-10 million people are living with Alzheimer's disease (AD) worldwide. Senile plaques composed of ß-amyloid (Aß) are a pathological hallmark of Alzheimer's disease. Presenilin 2 (PS2) mutations increase Aß generation in the brains of AD patients. The Aß is generated through the sequential cleavage of amyloid precursor protein by ß- and γ-secretases. Additionally, increasing evidences suggest that estrogen can reduce the development of AD via regulation of ß-secretases activity and beta-site APP-cleaving enzyme (BACE1) expression. But the underlying correlation mechanism of Aß generation by PS2 mutations and estrogen remains to be clarified. To investigate the anti-amyloidogenesis effect of estrogen in a PS2 mutative condition, we examined memory impairment in ovariectomized PS2 mutation (N141I) mice in which cognitive function was assessed by the Morris water maze test and passive avoidance test. In addition, Western blot analysis, immunostaining, immunofluorescence staining, ELISA and enzyme activity assays were used to examine the degree of Aß deposition in the brains. In the present study, Aß accumulated more in the ovariectomized PS2 mutant mice brain, and greatly worsened memory impairment and glial activation as well as neurogenic inflammation. In parallel with increased memory impairment, activity of ß-secretase and expression of the BACE1 increased inovariectomized PS2 mutant mice. Much higher activity of NF-κB was observed by EMSA in ovariectomized PS2 mutant mice. In addition, the Aß level was decreased by treatment of ß-estradiol through inhibiting BACE1 expression in PS2 transfacted PC12 cells. These results suggest that mutation of PS2 can lead to NF-κB mediate amyloidogensis, and this effect can be amplified by the absence of estrogen.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Amiloide/biossíntese , Estrogênios/deficiência , Transtornos da Memória/metabolismo , NF-kappa B/metabolismo , Presenilina-2/metabolismo , Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Cognição , Estrogênios/metabolismo , Feminino , Masculino , Transtornos da Memória/genética , Camundongos , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Placa Amiloide/metabolismo , Presenilina-2/genética , Transdução de Sinais
3.
J Nanosci Nanotechnol ; 15(2): 1499-502, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353679

RESUMO

We report a TiO2 nanotubes (NTs)-based Electrochemical luminescence (ECL) cell. The ECL cell was fabricated using the electrode of TiO2 NTs and Ru(II) complex (Ru(bpy)2+(3)) as a luminescence materials. The fabricated ECL cell is composed of F-doped SnO2 (FTO) glass/Ru(II)/TiO2 NTs/Ti plate. At a bias voltage of 3 V, the measured ECL efficiencies were 0 Im/W for cell without NTs, 0.03 Im/W for NTs-6.5 µm, 0.07 Im/W for NTs-8 µm and 0.1 Im/W for NTs-10 µm, respectively. The use of Ti02 NTs increases ECL intensities by about 2 times compared to the typical ECL cell without the use of TiO2 NTs.


Assuntos
Iluminação/instrumentação , Medições Luminescentes/instrumentação , Nanotubos/química , Nanotubos/ultraestrutura , Titânio/química , Campos Eletromagnéticos , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Nanotubos/efeitos da radiação , Tamanho da Partícula , Propriedades de Superfície , Titânio/efeitos da radiação
4.
J Neurosci Res ; 87(5): 1115-22, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19006082

RESUMO

The supratrigeminal region (Vsup) is important for coordination of smooth jaw movement. However, little is known about the synaptic connections of the Vsup premotoneurons with the trigeminal motor neurons. In the present study, we examined axon terminals of Vsup premotoneurons in the contralateral trigeminal motor nucleus (Vmo) by a combination of anterograde tracing with cholera toxin B-horseradish peroxidase (CTB-HRP), postembedding immunohistochemistry for the amino acid transmitters glutamate, GABA, and glycine, and electron microscopy. Tracer injections resulted in anterograde labeling of axon terminals of the Vsup premotoneurons in the motor trigeminal nucleus (Vmo). The labeled boutons in Vmo exhibited immunoreactivity for glutamate, GABA, or glycine: glutamate-immunopositive boutons (69%) were more frequently observed than GABA- or glycine-immunopositive boutons (19% and 12%, respectively). Although most labeled boutons (97%) made synaptic contacts with a single postsynaptic dendrite, a few glutamate-immunopositive boutons (3%) showed synaptic contact with two dendrites. No labeled boutons participated in axoaxonic synaptic contacts. Most labeled boutons (78%) were presynaptic to dendritic shafts, and the remaining 22% were presynaptic to somata or primary dendrites. A large proportion of GABA- or glycine-immunopositive boutons (40%) were presynaptic to somata or primary dendrites, whereas most glutamate-immunopositive boutons (86%) were presynaptic to dendritic shafts. These results indicate that axon terminals of Vsup premotoneurons show simple synaptic connection with Vmo neurons. This may provide the anatomical basis for the neural information processing responsible for jaw movement control.


Assuntos
Ácido Glutâmico/metabolismo , Glicina/metabolismo , Terminações Pré-Sinápticas/ultraestrutura , Núcleos do Trigêmeo/ultraestrutura , Ácido gama-Aminobutírico/metabolismo , Animais , Toxina da Cólera/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Imuno-Histoquímica , Masculino , Microinjeções , Microscopia Eletrônica , Terminações Pré-Sinápticas/metabolismo , Ratos , Ratos Sprague-Dawley , Núcleos do Trigêmeo/metabolismo
5.
Philos Trans A Math Phys Eng Sci ; 362(1815): 337-47; discussion 347-9, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15306524

RESUMO

The terahertz (THz) regime (0.1-10 THz) is rich with emerging possibilities in sensing, imaging and communications, with unique applications to screening for weapons, explosives and biohazards, imaging of concealed objects, water content and skin. Here we present initial surveys to evaluate the possibility of sensing plastic explosives and bacterial spores using field-deployable electronic THz techniques based on short-pulse generation and coherent detection using nonlinear transmission lines and diode sampling bridges. We also review the barriers and approaches to achieving greater sensing-at-a-distance (stand-off) capabilities for THz sensing systems. We have made several reflection measurements of metallic and non-metallic targets in our laboratory, and have observed high contrast relative to reflection from skin. In particular, we have taken small quantities of energetic materials such as plastic explosives and a variety of Bacillus spores, and measured them in transmission and in reflection using a broadband pulsed electronic THz reflectometer. The pattern of reflection versus frequency gives rise to signatures that are remarkably specific to the composition of the target, even though the target's morphology and position is varied. Although more work needs to be done to reduce the effects of standing waves through time-gating or attenuators, the possibility of mapping out this contrast for imaging and detection is very attractive.


Assuntos
Bactérias/isolamento & purificação , Eletrônica , Monitoramento Ambiental/métodos , Substâncias Perigosas/análise , Medidas de Segurança , Espectrofotometria Infravermelho/métodos , Guerra , Guerra Biológica/prevenção & controle , Bioterrorismo/prevenção & controle , Substâncias para a Guerra Química/análise , Monitoramento Ambiental/instrumentação , Raios Infravermelhos , Micro-Ondas , Medição de Risco/métodos , Espectrofotometria Infravermelho/instrumentação , Espectrofotometria Infravermelho/tendências
6.
J Comp Neurol ; 463(1): 13-24, 2003 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-12811799

RESUMO

Previous studies provide evidence that a structure/function correlation exists in the distinct zones of the trigeminal sensory nuclei. To evaluate this relationship, we examined the ultrastructure of afferent terminals from the tooth pulp in the rat trigeminal sensory nuclei: the principalis (Vp), the dorsomedial part of oral nucleus (Vdm), and the superficial layers of caudalis (Vc), by using transganglionic transport of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). A total of 93 labeled boutons were serially sectioned, in which some sections were incubated with gamma-aminobutyric acid (GABA) antiserum. Almost all labeled boutons formed asymmetric contact with nonprimary dendrites, in which more than half of labeled boutons in the Vc made synapses with their spines. The labeled boutons could be divided into two types on the basis of numbers of dense-cored vesicles (DCVs) in a boutons: S-type and DCV-type. Almost all labeled boutons in the Vp and Vdm were S-type, whereas two types were distributed evenly in the Vc. In contrast to DCV-type boutons, the S-type was frequently postsynaptic to unlabeled axon terminals containing a mixture of round, oval, and flattened vesicles (p-endings) and forming symmetrical synapses. Most p-endings examined were immunoreactive to GABA. The frequency of axoaxonic contacts was higher for labeled boutons in the Vp than in the Vdm and Vc. These results suggest that the three structures of trigeminal sensory nuclei serve distinct functions in nociceptive processing.


Assuntos
Vias Aferentes/citologia , Polpa Dentária/inervação , Terminações Pré-Sinápticas/ultraestrutura , Núcleos do Trigêmeo/citologia , Animais , Masculino , Microscopia Eletrônica , Ratos , Ratos Sprague-Dawley , Sinapses/ultraestrutura , Dente/inervação , Núcleos do Trigêmeo/química , Ácido gama-Aminobutírico/análise
7.
Phys Med Biol ; 47(21): 3777-87, 2002 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-12452568

RESUMO

By illuminating the sample with a broadband 10-300 GHz stimulus and coherently detecting the response, we obtain reflection and transmission spectra of common powdered substances, and compare them as a starting point for distinguishing concealed threats in envelopes and on personnel. Because these samples are irregular and their dielectric properties cannot be modulated, however, the spectral information we obtain is largely qualitative. To show how to gain quantitative information on biological species at micro- and millimetre-wave frequencies, we introduce thermal modulation of a globular protein in solution, and show that changes in single-wavelength microwave reflections coincide with accepted visible absorption spectra, pointing the way towards gaining quantitative chemical and biological spectra from broadband terahertz systems.


Assuntos
Bacillus anthracis/química , Bacillus cereus/química , Fenômenos Eletromagnéticos/métodos , Micro-Ondas , Ribonucleases/análise , Análise Espectral/métodos , Animais , Bacillus anthracis/efeitos da radiação , Bacillus cereus/efeitos da radiação , Bioterrorismo/prevenção & controle , Bovinos , Campos Eletromagnéticos , Fenômenos Eletromagnéticos/instrumentação , Substâncias Macromoleculares , Pâncreas/enzimologia , Pós/química , Pós/efeitos da radiação , Conformação Proteica , Ribonucleases/química , Ribonucleases/efeitos da radiação , Espalhamento de Radiação , Medidas de Segurança , Sensibilidade e Especificidade , Análise Espectral/instrumentação
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