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1.
Am J Trop Med Hyg ; 97(6): 1686-1690, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29141715

RESUMO

We report the first isolation of Anaplasma phagocytophilum in South Korea. A 61-year-old woman presented with a 6-day history of fever, headache, and myalgia. Initial investigation showed neutropenia and thrombocytopenia. We diagnosed human granulocytic anaplasmosis by microscopic examination and serologic testing. The patient recovered fully without antibiotic therapy. The isolate was obtained from the patient's blood by cell culture and mouse inoculation. Its identity was confirmed by an immunofluorescence assay, sequencing of the 16S rRNA gene, msp2 (p44), and ankA genes, and staining and electron microscopy of morulae of A. phagocytophilum in cultured human promyelocytic leukemia HL-60 cells.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Ehrlichiose/diagnóstico , Anaplasma phagocytophilum/genética , Animais , Antibacterianos/uso terapêutico , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Modelos Animais de Doenças , Ehrlichiose/tratamento farmacológico , Ehrlichiose/microbiologia , Feminino , Células HL-60 , Humanos , Camundongos , Camundongos Endogâmicos C3H , Pessoa de Meia-Idade , RNA Ribossômico 16S/isolamento & purificação , República da Coreia
2.
Autophagy ; 11(1): 100-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25484073

RESUMO

Autophagy is one of the main mechanisms in the pathophysiology of neurodegenerative disease. The accumulation of autophagic vacuoles (AVs) in affected neurons is responsible for amyloid-ß (Aß) production. Previously, we reported that SUMO1 (small ubiquitin-like modifier 1) increases Aß levels. In this study, we explored the mechanisms underlying this. We investigated whether AV formation is necessary for Aß production by SUMO1. Overexpression of SUMO1 increased autophagic activation, inducing the formation of LC3-II-positive AVs in neuroglioma H4 cells. Consistently, autophagic activation was decreased by the depletion of SUMO1 with small hairpin RNA (shRNA) in H4 cells. The SUMO1-mediated increase in Aß was reduced by the autophagy inhibitors (3-methyladenine or wortmannin) or genetic inhibitors (siRNA targeting ATG5, ATG7, ATG12, or HIF1A), respectively. Accumulation of SUMO1, ATG12, and LC3 was seen in amyloid precursor protein transgenic mice. Our results suggest that SUMO1 accelerates the accumulation of AVs and promotes Aß production, which is a key mechanism for understanding the AV-mediated pathophysiology of Alzheimer disease.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Autofagia , Proteína SUMO-1/metabolismo , Peptídeos beta-Amiloides/ultraestrutura , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Encéfalo/metabolismo , Linhagem Celular Tumoral , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Placa Amiloide/metabolismo , RNA Interferente Pequeno/metabolismo , Transfecção , Regulação para Cima
3.
FEBS Lett ; 588(17): 3081-8, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-24952354

RESUMO

Sulforaphane (SFN), an activator of nuclear factor E2-related factor 2 (Nrf2), has been reported to induce autophagy in several cells. However, little is known about its signaling mechanism of autophagic induction. Here, we provide evidence that SFN induces autophagy with increased levels of LC3-II through extracellular signal-regulated kinase (ERK) activation in neuronal cells. Pretreatment with NAC (N-acetyl-l-cysteine), a well-known antioxidant, completely blocked the SFN-induced increase in LC3-II levels and activation of ERK. Knockdown or overexpression of Nrf2 did not affect autophagy. Together, the results suggest that SFN-mediated generation of reactive oxygen species (ROS) induces autophagy via ERK activation, independent of Nrf2 activity in neuronal cells.


Assuntos
Autofagia/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Isotiocianatos/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Humanos , Camundongos , Neurônios/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sulfóxidos
4.
J Neurotrauma ; 29(7): 1530-8, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22087764

RESUMO

Osteopontin (OPN), an adhesive glycoprotein, has recently been proposed to act as an opsonin that facilitates phagocytosis of neuronal debris by macrophages in the ischemic brain. The present study was designed to elucidate the process whereby OPN binds to neuronal cell debris in a rat model of ischemic stroke. Significant co-localization of the OPN protein and calcium deposits in the ischemic core were observed by combining alizarin red staining and OPN immunohistochemistry. In addition, electron microscopy (EM) using the osmium/potassium dichromate method revealed that electron-dense precipitates, typical of calcium deposits, were localized mainly along the periphery of putative degenerating neurites. This topical pattern of calcium precipitates resembled the distribution of OPN as detected by immunogold-silver EM. Combining immunogold-silver EM and electron probe microanalysis further demonstrated that the OPN protein was localized at the periphery of cell debris or degenerating neurites, corresponding with locally higher concentrations of calcium and phosphorus, and that the relative magnitude of OPN accumulation was comparable to that of calcium and phosphorus. These data suggest that calcium precipitation provides a matrix for the binding of the OPN protein within the debris or degenerating neurites induced by ischemic injury. Therefore, OPN binding to calcium deposits may be involved in phagocytosis of such debris, and may participate in the regulation of ectopic calcification in the ischemic brain.


Assuntos
Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Cálcio/metabolismo , Osteopontina/metabolismo , Animais , Apoptose/fisiologia , Encéfalo/patologia , Isquemia Encefálica/patologia , Calcinose/metabolismo , Calcinose/patologia , Modelos Animais de Doenças , Microanálise por Sonda Eletrônica/métodos , Masculino , Neurônios/metabolismo , Neurônios/patologia , Neurônios/ultraestrutura , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia
5.
J Invest Dermatol ; 130(4): 1063-72, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19940858

RESUMO

Low-frequency sonophoresis (LFS) has been shown to disrupt the structure of stratum corneum (SC) lipid bilayers and enhance SC permeability. In this study, we examined the penetration pathway of lanthanum nitrate (LaNO(3)) tracer in viable epidermis after combined treatment of LFS and tape stripping (TS), as a physical enhancer, or oleic acid (OA) application, as a chemical enhancer, using transmission electron microscopy (TEM). As a positive control, we visualized the passive diffusion pathway of LaNO(3) and iron oxide (Fe(3)O(4)) nanoparticles after the incision of hairless mouse skin. Next, we applied LFS immediately after TS or OA application and visualized the penetration pathway of LaNO(3). Each treatment showed restricted penetration to the SC-stratum granulosum (SG) interface or upper SG layer. However, the additional application of LFS induced diffuse intracellular distribution of LaNO(3) throughout the viable epidermis. Quantitative analysis also revealed that combined treatment significantly increases LaNO(3) penetration into viable epidermis when compared with each treatment. Our ultrastructural findings show the synergistic effect of LFS and TS or OA application on transdermal drug delivery. We also found that this combined treatment enhances the penetration of LaNO(3) through the viable epidermis through an intracellular pathway.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Epiderme/metabolismo , Compostos Férricos/farmacocinética , Lantânio/farmacocinética , Nanopartículas , Ultrassom , Administração Cutânea , Animais , Difusão , Sistemas de Liberação de Medicamentos/instrumentação , Epiderme/ultraestrutura , Feminino , Compostos Férricos/administração & dosagem , Lantânio/administração & dosagem , Camundongos , Camundongos Pelados , Microscopia Eletrônica de Transmissão , Ácido Oleico/farmacocinética
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