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1.
RSC Adv ; 13(25): 17114-17120, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37293473

RESUMO

Silicon has been considered to be one of the most promising anode active materials for next-generation lithium-ion batteries due to its large theoretical capacity (4200 mA h g-1, Li22Si5). However, silicon anodes suffer from degradation due to large volume expansion and contraction. To control the ideal particle morphology, an experimental method is required to analyze anisotropic diffusion and surface reaction phenomena. This study investigates the anisotropy of the silicon-lithium alloying reaction using electrochemical measurements and Si K-edge X-ray absorption spectroscopy on silicon single crystals. During the electrochemical reduction process in lithium-ion battery systems, the continuous formation of solid electrolyte interphase (SEI) films prevents the achievement of steady-state conditions. Instead, the physical contact between silicon single crystals and lithium metals can prevent the effect of SEI formation. The apparent diffusion coefficient and the surface reaction coefficient are determined from the progress of the alloying reaction analyzed by X-ray absorption spectroscopy. While the apparent diffusion coefficients show no clear anisotropy, the apparent surface reaction coefficient of Si (100) is more significant than that of Si (111). This finding indicates that the surface reaction of silicon governs the anisotropy of practical lithium alloying reaction for silicon anodes.

2.
Pharmaceutics ; 14(5)2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35631596

RESUMO

In this study, we evaluated the use of 15-(4-123I-iodophenyl)-3(R,S)-methylpentadecanoic acid (123I-BMIPP) to visualize fatty acid metabolism in bacteria for bacterial infection imaging. We found that 123I-BMIPP, which is used for fatty acid metabolism scintigraphy in Japan, accumulated markedly in Escherichia coli EC-14 similar to 18F-FDG, which has previously been studied for bacterial imaging. To elucidate the underlying mechanism, we evaluated changes in 123I-BMIPP accumulation under low-temperature conditions and in the presence of a CD36 inhibitor. The uptake of 123I-BMIPP by EC-14 was mediated via the CD36-like fatty-acid-transporting membrane protein and accumulated by fatty acid metabolism. In model mice infected with EC-14, the biological distribution and whole-body imaging were assessed using 123I-BMIPP and 18F-FDG. The 123I-BMIPP biodistribution study showed that, 8 h after infection, the ratio of 123I-BMIPP accumulated in infected muscle to that in control muscle was 1.31 at 60 min after 123I-BMIPP injection. In whole-body imaging 1.5 h after 123I-BMIPP administration and 9.5 h after infection, infected muscle exhibited a 1.33-times higher contrast than non-infected muscle. Thus, 123I-BMIPP shows potential for visualizing fatty acid metabolism of bacteria for imaging bacterial infections.

3.
Epilepsia Open ; 7(2): 332-343, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35445562

RESUMO

OBJECTIVE: This study aimed to identify the recurrence rate of genetic generalized epilepsy (GGE) and risk factors for recurrence after antiseizure medication (ASM) withdrawal in adolescent patients. METHODS: We retrospectively reviewed medical records of patients with GGE who were included in the registry at the Department of Child Neurology, National Hospital Organization Nishiniigata Chuo Hospital from 2000 through 2020. The eligibility criteria were as follows: onset of epileptic seizures at <15 years of age, treatment with an ASM, and attempted treatment withdrawal at 10-19 years of age. The rates of seizure recurrence after drug withdrawal were evaluated. Moreover, several variables were evaluated as predictors of recurrence. RESULTS: In total, 77 patients with GGE (21, 13, and 43 patients with juvenile myoclonic epilepsy [JME], juvenile absence epilepsy [JAE], and epilepsy with generalized tonic-clonic seizures alone [EGTCSA], respectively) were included in this study. Recurrence was detected in 68% of patients with GGE (86%, 31%, and 70% of patients with JME, JAE, and EGTCSA, respectively). Recurrence rates for patients who developed epilepsy at ≥13 years of age, those who started dose reduction at ≥16 years of age, those who exhibited a seizure-free period of <36 months before withdrawal, and those who chose to discontinue treatment at their own discretion were significantly higher than those for their counterparts. Multivariate analysis revealed that initiation of dose reduction at ≥16 years of age was associated with increased recurrence risk. Meanwhile, a diagnosis of JAE was associated with decreased recurrence risk. All patients with JAE were treated with valproic acid. SIGNIFICANCE: Antiseizure medication withdrawal at ≥16 years of age and a diagnosis other than JAE may be independent risk factors for seizure recurrence after drug withdrawal in adolescent patients.


Assuntos
Epilepsia Tipo Ausência , Epilepsia Generalizada , Epilepsia Mioclônica Juvenil , Síndrome de Abstinência a Substâncias , Adolescente , Adulto , Anticonvulsivantes/uso terapêutico , Criança , Pré-Escolar , Epilepsia Generalizada/tratamento farmacológico , Epilepsia Generalizada/genética , Humanos , Estudos Retrospectivos , Fatores de Risco , Convulsões/tratamento farmacológico , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Adulto Jovem
4.
J Microbiol Methods ; 184: 106214, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33811935

RESUMO

Potent fungicidal activity is one of the key factors of antifungals to overcome invasive pulmonary aspergillosis (IPA). To date, quantification of Aspergillus DNA in the lungs and galactomannan (GM) in serum or bronchoalveolar lavage fluid have been developed as general methods for measuring fungal burden in IPA animal models. However, GM quantification is not supposed to be a suitable method for precise evaluation of the fungicidal effects of antifungals, because killed Aspergillus hyphae can release GM for a certain period until they are eliminated by the host. Therefore, in terms of detecting viable fungal burden of Aspergillus, quantification of Aspergillus DNA has been thought to be a suitable method. Here, to obtain a method with much higher sensitivity, we applied reverse transcription quantitative PCR (RT-qPCR) for A. fumigatus 18S ribosomal RNA to measure the viable fungal burden in murine IPA models. Prior to in vivo tests, we confirmed that the sensitivity of 18S rRNA was nearly 50-fold higher than that of 18S ribosomal DNA in vitro. This highly sensitive method made it possible to evaluate the fungicidal effects of antifungals in a low-inoculation murine IPA model. In this model, single administrations of higher doses of voriconazole and posaconazole, which have fungicidal activity, were able to display fungicidal effects with ≥1 log10 reductions by 18S rRNA quantification, whereas significant reductions in serum GM were not observed. These results suggest that 18S rRNA quantification is a powerful tool for screening novel antifungals with potent fungicidal activity only after a single administration.


Assuntos
Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/genética , Aspergilose Pulmonar Invasiva/microbiologia , RNA Ribossômico 18S/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/isolamento & purificação , DNA Fúngico/genética , Humanos , Aspergilose Pulmonar Invasiva/diagnóstico , Masculino , Camundongos , Camundongos Endogâmicos DBA , Viabilidade Microbiana , Sensibilidade e Especificidade
5.
ACS Appl Mater Interfaces ; 12(1): 428-435, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31830786

RESUMO

Fluoride-shuttle batteries (FSBs), which are based on fluoride-ion transfer, have attracted attention because of their high theoretical energy densities. The fluorination and defluorination reactions at the electrodes are the possible rate-determining steps in FSBs, and understanding the mechanism is important to achieve smooth charge/discharge. In this study, we discuss the thermodynamically favored pathways for the fluorination and defluorination reactions and compare the reactions through the solid-solution and two-phase-coexistent states by density functional theory (DFT) calculations. The free energies of the solid-solution and two-phase states approximate the energies calculated by DFT, and their accuracy was validated by comparison with experimental formation enthalpies and free energies. The relative formation enthalpies of typical, transition, and relativistic metal (Tl, Pb, and Bi) fluorides are well reproduced by DFT calculations within 0.1, 0.2, and 0.4 eV, respectively. We also show that the reaction pathway can be determined by comparing the formation enthalpies of the metal fluoride H, a fluorine vacancy HV, and an interstitial fluorine defect HI from the simple selection rule. The enthalpy relation of HI > H > -HV observed in all the calculations strongly suggests that fluorination and defluorination in FSB electrodes occur by a two-phase reaction. This fluorination and defluorination mechanism will be useful to clarify the rate-determining step in FSBs.

6.
ChemSusChem ; 12(2): 527-534, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30450797

RESUMO

Fluoride shuttle batteries (FSBs), which utilize defluorination of metal fluorides and fluorination of the resultant metals, are expected to have high energy densities. In situ Raman microscopy was conducted during FSB reactions of a nearly-2D cluster of orthorhombic BiF3 microparticles partly embedded in a gold-plated film (o-BiF3 /gold). At a high overpotential, defluorination of the surface of an o-BiF3 particle (or cluster) was almost completed within approximately 120 s. At a low over potential, defluorination proceeded from the contours of the cluster that was in contact with the gold to the center of the cluster, suggesting that the rate-limiting process was electronic diffusion. Conversely, fluorination proceeded uniformly at the surface of the cluster to form BiF3 with a cubic structure (c-BiF3 ). The results will lead to the establishment of a strategy for efficient use of active materials with low electronic and ionic conductivities.

7.
J Chem Phys ; 147(12): 124701, 2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28964018

RESUMO

Clarification of the details of the interface structure between liquids and solids is crucial for understanding the fundamental processes of physical functions. Herein, we investigate the structure of the interface between tetraglyme and graphite and propose a model for the interface structure based on the observation of frequency-modulation atomic force microscopy in liquids. The ordering and distorted adsorption of tetraglyme on graphite were observed. It is found that tetraglyme stably adsorbs on graphite. Density functional theory calculations supported the adsorption structure. In the liquid phase, there is a layered structure of the molecular distribution with an average distance of 0.60 nm between layers.

8.
Ann Neurol ; 80(4): 554-65, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27490250

RESUMO

OBJECTIVE: To clarify the histopathological alterations of microglia in the brains of patients with hereditary diffuse leukoencephalopathy with spheroids (HDLS) caused by mutations of the gene encoding the colony stimulating factor-1 receptor (CSF-1R). METHODS: We examined 5 autopsied brains and 1 biopsy specimen from a total of 6 patients with CSF-1R mutations. Detailed immunohistochemical, biochemical, and ultrastructural features of microglia were examined, and quantitative analyses were performed. RESULTS: In layers 3 to 4 of the frontal cortex in HDLS brains, microglia showed relatively uniform and delicate morphology, with thin and winding processes accompanying knotlike structures, and significantly smaller areas of Iba1 immunoreactivity and lower numbers of Iba1-positive cells were evident in comparison with control brains. On the other hand, in layers 5 to 6 and the underlying white matter, microglia were distributed unevenly; that is, in some areas they had accumulated densely, whereas in others they were scattered. Immunoblot analyses of microglia-associated proteins, including CD11b and DAP12, revealed that HDLS brains had significantly lower amounts of these proteins than diseased controls, although Ki-67-positive proliferative microglia were not reduced. Ultrastructurally, the microglial cytoplasm and processes in HDLS showed vesiculation of the rough endoplasmic reticulum and disaggregated polyribosomes, indicating depression of protein synthesis. On the other hand, macrophages were immunonegative for GLUT-5 or P2ry12, indicating that they were derived from bone marrow. INTERPRETATION: The pathogenesis of HDLS seems to be associated with microglial vulnerability and morphological alterations. Ann Neurol 2016;80:554-565.


Assuntos
Córtex Cerebelar/patologia , Lobo Frontal/patologia , Leucoencefalopatias/patologia , Microglia/patologia , Substância Branca/patologia , Autopsia , Biópsia , Humanos , Leucoencefalopatias/metabolismo , Microglia/ultraestrutura , Receptor de Fator Estimulador de Colônias de Macrófagos/genética
9.
Brain Dev ; 38(10): 950-953, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27381655

RESUMO

Megalencephalic polymicrogyria syndromes include megalencephaly-capillary malformation and megalencephaly-polymicrogyria-polydactyly-hydrocephalus. Recent genetic studies have identified that genes in the PI3K-AKT pathway are involved in the pathogenesis of these disorders. Herein, we report a patient who presented with developmental delay, epilepsy and peculiar neuroimaging findings of megalencephaly, polymicrogyria, and symmetrical band heterotopia in the periventricular region. The heterotopias exhibited inhomogeneous signals with undulatory mixtures of gray and white matter, resembling ribbon-like heterotopia, with a predominance in the temporal to occipital regions. These neuroradiological findings were not consistent with those in known megalencephalic polymicrogyria syndromes. No genetic abnormality was identified through whole-exome sequencing. The neuroimaging findings of this patient may represent a novel cortical malformation involving megalencephaly with polymicrogyria and ribbon-like band heterotopia.


Assuntos
Encéfalo/diagnóstico por imagem , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/diagnóstico por imagem , Megalencefalia/diagnóstico por imagem , Polimicrogiria/diagnóstico por imagem , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/genética , Feminino , Técnicas de Genotipagem , Humanos , Lactente , Imageamento por Ressonância Magnética , Megalencefalia/genética , Análise em Microsséries , Polimicrogiria/genética
10.
Antiviral Res ; 109: 110-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24997412

RESUMO

The purpose of this study was to investigate the relationship between pharmacokinetic (PK) parameters of intravenous (IV) peramivir and in vivo antiviral activity pharmacodynamic (PD) outcomes in a mouse model of influenza virus infection. Peramivir was administrated to mice in three dosing schedules; once, twice and four times after infection of A/WS/33 (H1N1). The survival rate at day 14 after virus infection was employed as the antiviral activity outcome for analysis. The relationship between day 14 survival and PK parameters, including area under the concentration-time curve (AUC), maximum concentration (Cmax) and time that drug concentration exceeds IC95 (T(>IC95)), was estimated using a logistic regression model, and model fitness was evaluated by calculation of the Akaike information criterion (AIC) index. The AIC indices of AUC, Cmax and T(>IC95) were about 114, 151 and 124, respectively. The AIC of AUC and T(>IC95) were smaller than that of Cmax. Therefore, both AUC and T(>IC95) were the PK parameters that correlated best with the antiviral activity of peramivir IV against influenza virus infection in mice.


Assuntos
Antivirais/farmacocinética , Ciclopentanos/farmacocinética , Guanidinas/farmacocinética , Influenza Humana/tratamento farmacológico , Ácidos Carbocíclicos , Animais , Antivirais/administração & dosagem , Ciclopentanos/administração & dosagem , Modelos Animais de Doenças , Feminino , Guanidinas/administração & dosagem , Humanos , Influenza Humana/virologia , Camundongos , Camundongos Endogâmicos BALB C
11.
Neurology ; 82(2): 139-48, 2014 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-24336230

RESUMO

OBJECTIVE: To clarify the genetic, clinicopathologic, and neuroimaging characteristics of patients with hereditary diffuse leukoencephalopathy with spheroids (HDLS) with the colony stimulating factor 1 receptor (CSF-1R) mutation. METHODS: We performed molecular genetic analysis of CSF-1R in patients with HDLS. Detailed clinical and neuroimaging findings were retrospectively investigated. Five patients were examined neuropathologically. RESULTS: We found 6 different CSF-1R mutations in 7 index patients from unrelated Japanese families. The CSF-1R mutations included 3 novel mutations and 1 known missense mutation at evolutionarily conserved amino acids, and 1 novel splice-site mutation. We identified a novel frameshift mutation. Reverse transcription PCR analysis revealed that the frameshift mutation causes nonsense-mediated mRNA decay by generating a premature stop codon, suggesting that haploinsufficiency of CSF-1R is sufficient to cause HDLS. Western blot analysis revealed that the expression level of CSF-1R in the brain from the patients was lower than from control subjects. The characteristic MRI findings were the involvement of the white matter and thinning of the corpus callosum with signal alteration, and sequential analysis revealed that the white matter lesions and cerebral atrophy relentlessly progressed with disease duration. Spotty calcifications in the white matter were frequently observed by CT. Neuropathologic analysis revealed that microglia in the brains of the patients demonstrated distinct morphology and distribution. CONCLUSIONS: These findings suggest that patients with HDLS, irrespective of mutation type in CSF-1R, show characteristic clinical and neuroimaging features, and that perturbation of CSF-1R signaling by haploinsufficiency may play a role in microglial dysfunction leading to the pathogenesis of HDLS.


Assuntos
Gliose/congênito , Haploinsuficiência/genética , Leucoencefalopatias/genética , Leucoencefalopatias/patologia , Receptores de Fator Estimulador de Colônias/genética , Adulto , Idade de Início , Idoso , Povo Asiático , Western Blotting , Encéfalo/patologia , Análise Mutacional de DNA , Progressão da Doença , Feminino , Gliose/genética , Gliose/patologia , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Mutação/fisiologia , Fosforilação , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Tomografia Computadorizada por Raios X
12.
Neuropathology ; 34(1): 1-10, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23889567

RESUMO

Medulloblastoma (MB) is a malignant cerebellar tumor arising in children, and its ontogenesis is regulated by Sonic Hedgehog (Shh) signaling. No data are available regarding the correlation between expression of Gli3, a protein lying downstream of Shh, and neuronal differentiation of MB cells, or the prognostic significance of these features. We re-evaluated the histopathological features of surgical specimens of MB taken from 32 patients, and defined 15 of them as MB with neuronal differentiation (ND), three as MB with both glial and neuronal differentiation (GD), and 14 as differentiation-free (DF) MB. Gli3-immunoreactivity (IR) was evident as a clear circular stain outlining the nuclei of the tumor cells. The difference in the frequency of IR between the ND+GD (94.4%) and DF (0%) groups was significant (P < 0.001). The tumor cells with ND showed IR for both Gli3 and neuronal nuclei. Ultrastructurally, Gli3-IR was observed at the nuclear membrane. The overall survival and event-free survival rates of the patients in the ND group were significantly higher than those in the other groups. The expression profile of Gli3 is of considerable significance, and the association of ND with this feature may be prognostically favorable in patients with MB.


Assuntos
Neoplasias Cerebelares/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Meduloblastoma/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Diferenciação Celular/fisiologia , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/ultraestrutura , Criança , Humanos , Fatores de Transcrição Kruppel-Like/análise , Masculino , Meduloblastoma/patologia , Meduloblastoma/ultraestrutura , Proteínas do Tecido Nervoso/análise , Prognóstico , Proteína Gli3 com Dedos de Zinco
13.
Phys Chem Chem Phys ; 15(19): 7286-94, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23575517

RESUMO

Homogeneously alloyed bimetallic particles of AuPd with an average size of ca. 2 nm were successfully prepared by simultaneous sputter deposition of Au and Pd in an ionic liquid in the absence of any additional stabilizing agents. The chemical composition of the AuPd alloy was tunable depending on the area fraction of Au plates in the Au-Pd binary targets for sputtering. The particles were immobilized on an HOPG surface by heat treatment along with the increase in the average size of particles from ca. 2 nm to ca. 7 nm. Ionic liquid species adsorbed on the as-prepared AuPd nanoparticle films on HOPG caused the prevention of electrocatalytic reactions, but repetition of potential sweep cycling in a basic aqueous solution removed the adsorbed ionic species, resulting in electrocatalytic oxidation of ethanol at the AuPd alloy nanoparticle-immobilized HOPG electrode. The electrocatalytic activity of AuPd nanoalloy particles varied upon changing the fraction of Au and Pd in the particles, and alloy particles having an Au fraction of ca. 0.61 exhibited the maximum activity against ethanol oxidation, being higher than the activity of the pure Pt surface.

14.
Adv Mater ; 22(11): 1196-221, 2010 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-20437507

RESUMO

Ionic liquids (ILs) including ambient-temperature molten salts, which exist in the liquid state even at room temperature, have a long research history. However, their applications were once limited because ILs were considered as highly moisture-sensitive solvents that should be handled in a glove box. After the first synthesis of moisture-stable ILs in 1992, their unique physicochemical properties became known in all scientific fields. ILs are composed solely of ions and exhibit several specific liquid-like properties, e.g., some ILs enable dissolution of insoluble bio-related materials and the use as tailor-made lubricants in industrial applications under extreme physicochemical conditions. Hybridization of ILs and other materials provides quasi-solid materials, which can be used to fabricate highly functional devices. ILs are also used as reaction media for electrochemical and chemical synthesis of nanomaterials. In addition, the negligible vapor pressure of ILs allows the fabrication of electrochemical devices that are operated under ambient conditions, and many liquid-vacuum technologies, such as X-ray photoelectron spectroscopy (XPS) analysis of liquids, electron microscopy of liquids, and sputtering and physical vapor deposition onto liquids. In this article, we review recent studies on ILs that are employed as functional advanced materials, advanced mediums for materials production, and components for preparing highly functional materials.


Assuntos
Líquidos Iônicos/química , Manufaturas
15.
Chem Commun (Camb) ; 46(12): 2082-4, 2010 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-20221499

RESUMO

The photoluminescence intensity of ZnS-AgInS(2) solid solution nanoparticles was remarkably enhanced by increasing the heating temperature to 180 degrees C, above which the emission was simply diminished, while ZnS coating of the particles resulted in further enhancement of PL intensity, giving the highest quantum yield of ca. 80%.

16.
Neuropathology ; 30(6): 627-33, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20113403

RESUMO

We report the autopsy findings of a 63-year-old man with neurofibromatosis type 1 (NF1), in whom widespread ischemic brain lesions caused by vasculopathy associated with the disorder were observed. The patient, who had café au lait macules, axillary freckling, and neurofibromas, was inarticulate of speech, had difficulty in maintaining a sitting position, and was hyporeactive at the age of 57 years. He then developed autonomic dysfunction, followed by consciousness disturbance and status epilepticus. Repeated MRI studies disclosed multiple, ill-defined lesions in the brain and progressive cerebral atrophy. The histopathological features of the lesions were those of ischemia that had occurred with spatiotemporal variability in the brain. Characteristically, many arteries in the subarachnoid space manifested accumulation of cells in the intimal layer: this hyperplasia had resulted in narrowing and occlusion of the lumen. Immunoblotting demonstrated a marked decrease of neurofibromin, the NF1 product, which is known to act as a functional molecule in the normal process of vascular maintenance and repair. This case provides useful information about the pathomechanisms underlying central nervous system manifestations in patients with NF1.


Assuntos
Isquemia Encefálica/etiologia , Isquemia Encefálica/patologia , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Neurofibromatose 1/complicações , Neurofibromatose 1/patologia , Adulto , Western Blotting , Humanos , Imageamento por Ressonância Magnética , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Adulto Jovem
17.
Phys Chem Chem Phys ; 12(8): 1804-11, 2010 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-20145845

RESUMO

Gold (Au) nanoparticles were prepared by sputter deposition of Au metal in an ionic liquid (IL) of 1-butyl-3-methylimidazolium hexafluorophosphate (BMI-PF6). The size of Au nanoparticles was increased from 2.6 to 4.8 nm by heat treatment at 373 K. The nanoparticles uniformly dispersed in the IL were densely immobilized on a glass substrate surface modified with a silane coupling agent having an imidazole functional group by spreading the Au particle IL solution on the substrates, followed by heat treatment at 373 K. The optical property of the thus-obtained films was tunable by controlling the size of Au nanoparticles in the IL and the degree of immobilization. An intense localized surface plasmon resonance (LSPR) peak was observed in each Au particle film, and the wavelength of the LSPR peak could be controlled by changing the size of nanoparticles in the IL solution before immobilization. Photoexcitation of the LSPR peak caused enhancement of the photoluminescence of CdTe nanoparticles immobilized on Au nanoparticle films, probably due to the locally enhanced electric field formed around Au nanoparticles.

18.
Neuropathology ; 30(2): 140-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19780981

RESUMO

Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Corticobasal degeneration (CBD) is a rare neurodegenerative disease affecting adults, being characterized clinically by a combination of extrapyramidal signs and focal cortical syndromes. In both diseases, tau deposits are a characteristic neuropathological feature. We report two new patients with autopsy-proven AD, in whom clinical diagnoses of CBD were made during life. The ages of the patients at onset were 52 and 67 years, and the disease durations were 9 and 15 years, respectively. At autopsy, both cases exhibited marked cortical atrophy with evident neuronal loss in the convex areas of the frontal and parietal lobes. Immunohistochemically, AT8-positive neurofibrillary tangles (NFTs) and Abeta-positive senile plaques (SPs) were widespread and abundant in the cerebral cortex (Alzheimer pathology stage VI/C of Braak and Braak), leading us to the final pathological diagnosis of AD. No tau lesions suggestive of CBD were observed, and the deep gray matter areas, including the substantia nigra, were unremarkable (exceptionally, only mild neuronal loss was noted in the putamen in case 2). These findings further strengthen the idea that in AD, neurodegeneration with tau and Abeta deposits may begin in the fronto-parietal neocortical areas, which are often preferentially affected in CBD, earlier than, or as early as the medial temporal lobe, and that extrapyramidal signs, such as rigidity and tremor, can occur in the absence of neuronal loss in the basal ganglia and substantia nigra.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Doenças Neurodegenerativas/diagnóstico , Emaranhados Neurofibrilares/patologia , Placa Amiloide/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Atrofia/metabolismo , Atrofia/patologia , Encéfalo/metabolismo , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Doenças Neurodegenerativas/metabolismo , Emaranhados Neurofibrilares/metabolismo , Placa Amiloide/metabolismo
19.
Brain Dev ; 32(6): 499-501, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19628347

RESUMO

We present a male infant with hemifacial seizures refractory to antiepileptic medication. Hemifacial spasms around the left eye were frequent during wakefulness and sleep since birth. He also had mild psychomotor retardation. Magnetic resonance imaging (MRI) revealed a large tumor in the left middle cerebellar peduncle. Ictal single photon emission computed tomography (SPECT) and ictal (18)F-fluorodeoxyglucose [(18)F-FDG] positron emission tomography (PET) revealed hyperperfusion and hyper glucose metabolism at the tumor. Total removal of the tumor resulted in complete disappearance of hemifacial seizures and improved psychomotor development, indicating that the cerebellar tumor caused hemifacial seizures. A histopathological study confirmed that the tumor was a ganglioglioma. This case and the literature on similar cases indicated that this was a new epileptic syndrome originating in the cerebellum. Early diagnosis and early complete removal of the epileptogenic lesion should be recommended for this syndrome.


Assuntos
Neoplasias Cerebelares/complicações , Ganglioglioma/complicações , Convulsões/etiologia , Anticonvulsivantes/uso terapêutico , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Neoplasias Cerebelares/diagnóstico , Neoplasias Cerebelares/cirurgia , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/etiologia , Deficiências do Desenvolvimento/cirurgia , Diagnóstico Precoce , Face , Fluordesoxiglucose F18 , Lateralidade Funcional , Ganglioglioma/diagnóstico , Ganglioglioma/cirurgia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Convulsões/diagnóstico , Convulsões/tratamento farmacológico , Resultado do Tratamento
20.
J Vet Med Sci ; 71(11): 1459-64, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19959896

RESUMO

It has been reported that administration of Candida albicans into mouse induces an antifungal activity in serum, which has been identified as transferrin. In the present study, we show that not only C. albicans, but also other fungus such as Cryptococcus neoformans or Aspergillus fumigatus similarly can induce an antifungal activity in mouse serum. This antifungal activity was inhibited by the addition of ferrous ion, indicating that the growth inhibition of C. albicans was due to deficiency of ferrous ion, which may be caused by transferrin. Indeed, addition of transferrin in an in vitro assay system using RPMI1640 culture medium inhibited the growth of C. albicans, C. neoformans or A. fumigatus. However, when C. albicans was grown in RPMI1640 medium with 10% fetal bovine serum (FBS), transferrin was unable to inhibit the growth of C. albicans, in sharp contrast, when C. albicans treated mouse serum was added instead of FBS, the growth of the organism was inhibited. Similar results were obtained when C. neoformans or A. fumigatus was used. Taken together, the results suggest that antifungal activity induced by C. albicans, C. neoformans or A. fumigatus was not due to transferrin but likely due to other unknown serum proteins, which may cut off the source of iron for the growth of these fungi.


Assuntos
Aspergilose/sangue , Candidíase/sangue , Criptococose/sangue , Transferrina/farmacologia , Animais , Aspergillus fumigatus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Meios de Cultura/química , Camundongos
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