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1.
Chemistry ; 27(22): 6706-6712, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33403705

RESUMO

The nanostructural design of heterogeneous catalysts has often been demanded for assessing synergetic effects, which should be developed further by using high-surface-area porous metal oxide supports. However, such opportunities have been undermined by the poor stability of ordered mesoporous structures. Herein, rational design is demonstrated to obtain nanocomposite catalysts showing improved NOx storage properties owing to the presence of Ba species over a well-designed mesoporous alumina (Al2 O3 ) support. It is found that Ba species are impregnated successfully only after the stabilization of the mesoporous structure by full crystallization of Al2 O3 frameworks to the γ-phase, with the formation of Pt nanoparticles coinciding with complete removal of organic components. All the insights during this synthetic procedure are essential for designing high-performance catalysts to purify and recover NOx molecules, and are applied for designing a variety of cutting-edge mesoporous nanocomposite catalysts.

2.
J Hazard Mater ; 398: 122791, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-32768855

RESUMO

The regulation of automobile exhaust gas, especially that concerning hazardous nitrogen oxide (called as NOx) becomes stricter year-by-year, which should be urgently corresponded for cleaning the NOx containing emission. According to surface affinity of γ-alumina to metal catalysts and its thermal stability, crystalline γ-alumina has been frequently utilized as catalyst supports showing relatively high specific surface area. From the viewpoint, we consider that highly porous alumina powders prepared using amphiphilic organic molecules are potential as such a catalyst support for improving NOx removing property. In this study, we report surface property of the mesoporous alumina powders against NOx molecules after crystallizing to its γ-phase and NOx storage property after impregnation of barium (Ba) acetate in the mesopores. Adsorption of NO with O2 on mesoporous γ-alumina powders without Ba species were more likely to be bridging bidentate than chelating bidentate nitrates (NO3-) with comparing to commercially available γ-alumina powders. After impregnating the Ba species, admitted NO molecules were oxidized with enough O2 and stored very strongly as ionic nitrate (NO3-) onto the Ba species even after heating at 500 °C. This preliminary study is helpful for designing mesoporous deNOx catalysts combined with unique storage/adsorption property.

3.
Langmuir ; 34(45): 13781-13787, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30336058

RESUMO

Considering the closed packing of supramolecular mediated cage-type (spherical) mesopores inside spherical particles that are typically obtained by the aerosol-assisted process, uniform mesopores cannot be packed so periodically and then the mesopores are less connected and/or occasionally isolated, leading to the formation of low-surface-area mesoporous particles. In this study, we proposed the controlled swelling of such cage-type mesopores for improving their connectivity. Actually, we succeeded in preparing high-surface-area mesoporous alumina powders using poly(oxyethylene)- block-poly(oxypropylene)- block-poly(oxyethylene) (EO nPO mEO n) type triblock copolymers such as Pluronic P123. The surface area of the mesoporous alumina powders was originally low (278 m2 g-1 without organic additives), which can be drastically increased up to ca. 540 m2 g-1 through the controlled welling with suitable addition of 1,3,5-trimethylbenzene and 1,3,5-triisopropylbenzene. The insight is promising for further development of the aerosol-assisted approach for recovering high-quality mesoporous powders and helpful for rational catalyst design by utilizing mesoporous alumina powders with extremely high surface area.

4.
J Anesth ; 32(5): 709-716, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30099599

RESUMO

PURPOSE: Equilibration rate constant is necessary to calculate effect-site concentration, which is useful to control drug effect. We developed pharmacodynamic models for published five compartmental pharmacokinetic models published by Wierda, Szenohradszky, Cooper, Alvarez-Gomez, and McCoy. METHODS: We used 3848 train-of-four ratios from 15 male and nine female patients (21-76 years; 44-93 kg body weight; 148-181 cm height; and 17.3-29.8 kg/m2 body mass index) as pharmacodynamic measures, which were collected at the start of 0.6 mg/kg rocuronium administration until the end of the surgery. Effect compartment was assumed to be connected to central compartment of the pharmacokinetic model with equilibration rate constant (ke0). Sigmoid Emax model was fitted to describe the relationship between train-of-four ratio and effect-site concentration. Age, sex, and body mass index were assessed as possible covariates of the following model parameters: ke0, effect-site concentration for half of maximum effect, and the steepness of the effect-site concentration versus effect relationship. RESULTS: The duration of neuromuscular monitoring was 69 (37-129) [median (range)] min. All pharmacodynamic models included age and three included sex as significant covariates. Ke0 values ranged between 0.0820 and 0.247 depending on the pharmacokinetic model. The time-courses of the effect-site concentration were similar among the pharmacodynamic models for Wierda, Cooper, and Alvarez-Gomez pharmacokinetic models, which were lower than that for the Szenohradszky pharmacokinetic model. CONCLUSION: Each pharmacodynamic model with the corresponding pharmacokinetic model can be described the time course of rocuronium effect appropriately. The required effect-site concentration of rocuronium for a pharmacodynamic effect was depending on the applied models.


Assuntos
Modelos Biológicos , Monitoração Neuromuscular/métodos , Rocurônio/administração & dosagem , Adulto , Idoso , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rocurônio/farmacocinética , Rocurônio/farmacologia , Adulto Jovem
5.
PLoS One ; 10(9): e0137429, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26367776

RESUMO

The pathogenesis of multiple sclerosis (MS), an autoimmune disease affecting the brain and spinal cord, remains poorly understood. Patients with MS typically present with recurrent episodes of neurological dysfunctions such as blindness, paresis, and sensory disturbances. Studies on experimental autoimmune encephalomyelitis (EAE) animal models have led to a number of testable hypotheses including a hypothetical role of altered gut microbiota in the development of MS. To investigate whether gut microbiota in patients with MS is altered, we compared the gut microbiota of 20 Japanese patients with relapsing-remitting (RR) MS (MS20) with that of 40 healthy Japanese subjects (HC40) and an additional 18 healthy subjects (HC18). All the HC18 subjects repeatedly provided fecal samples over the course of months (158 samples in total). Analysis of the bacterial 16S ribosomal RNA (rRNA) gene by using a high-throughput culture-independent pyrosequencing method provided evidence of a moderate dysbiosis in the structure of gut microbiota in patients with MS. Furthermore, we found 21 species that showed significant differences in relative abundance between the MS20 and HC40 samples. On comparing MS samples to the 158 longitudinal HC18 samples, the differences were found to be reproducibly significant for most of the species. These taxa comprised primarily of clostridial species belonging to Clostridia clusters XIVa and IV and Bacteroidetes. The phylogenetic tree analysis revealed that none of the clostridial species that were significantly reduced in the gut microbiota of patients with MS overlapped with other spore-forming clostridial species capable of inducing colonic regulatory T cells (Treg), which prevent autoimmunity and allergies; this suggests that many of the clostridial species associated with MS might be distinct from those broadly associated with autoimmune conditions. Correcting the dysbiosis and altered gut microbiota might deserve consideration as a potential strategy for the prevention and treatment of MS.


Assuntos
Clostridium/metabolismo , Disbiose/metabolismo , Microbioma Gastrointestinal , Esclerose Múltipla/microbiologia , Adulto , Bacteroidetes/genética , Bacteroidetes/metabolismo , Clostridium/classificação , Clostridium/genética , Disbiose/microbiologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Japão , Masculino , Esclerose Múltipla/fisiopatologia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de RNA
6.
Chemphyschem ; 16(9): 2015-20, 2015 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-25914350

RESUMO

The structure of FeOx species supported on γ-Al2 O3 was investigated by using Fe K-edge X-ray absorption fine structure (XAFS) and X-ray diffraction (XRD) measurements. The samples were prepared through the impregnation of iron nitrate on Al2 O3 and co-gelation of aluminum and iron sulfates. The dependence of the XRD patterns on Fe loading revealed the formation of α-Fe2 O3 particles at an Fe loading of above 10 wt %, whereas the formation of iron-oxide crystals was not observed at Fe loadings of less than 9.0 wt %. The Fe K-edge XAFS was characterized by a clear pre-edge peak, which indicated that the FeO coordination structure deviates from central symmetry and that the degree of FeOFe bond formation is significantly lower than that in bulk samples at low Fe loading (<9.0 wt %). Fe K-edge extended XAFS oscillations of the samples with low Fe loadings were explained by assuming an isolated iron-oxide monomer on the γ-Al2 O3 surface.

7.
Artigo em Inglês | MEDLINE | ID: mdl-24679089

RESUMO

Microbial contamination in unfinished beverages can occur when drinking directly from the bottle. Various microorganisms, including foodborne pathogens, are able to grow in these beverages at room temperature or in a refrigerator. In this study, we elucidated the characteristics of microorganism growth in bottled beverages under consuming condition models. Furthermore, we provide insight into the safety of partially consumed bottled beverages with respect to food hygiene. We inoculated microorganisms, including foodborne pathogens, into various plastic bottled beverages and analysed the dynamic growth of microorganisms as well as bacterial toxin production in the beverages. Eight bottled beverage types were tested in this study, namely green tea, apple juice drink, tomato juice, carbonated drink, sport drink, coffee with milk, isotonic water and mineral water, and in these beverages several microorganism types were used: nine bacteria including three toxin producers, three yeasts, and five moulds. Following inoculation, the bottles were incubated at 35°C for 48 h for bacteria, 25°C for 48 h for yeasts, and 25°C for 28 days for moulds. During the incubation period, the number of bacteria and yeasts and visible changes in mould-growth were determined over time. Our results indicated that combinations of the beverage types and microorganism species correlated with the degree of growth. Regarding factors that affect the growth and toxin-productivity of microorganisms in beverages, it is speculated that the pH, static/shaking culture, temperature, additives, or ingredients, such as carbon dioxide or organic matter (especially of plant origin), may be important for microorganism growth in beverages. Our results suggest that various types of unfinished beverages have microorganism growth and can include food borne pathogens and bacterial toxins. Therefore, our results indicate that in terms of food hygiene it is necessary to consume beverages immediately after opening the bottle.


Assuntos
Bactérias/crescimento & desenvolvimento , Bebidas/microbiologia , Ingestão de Líquidos , Microbiologia de Alimentos , Leveduras/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Higiene/normas , Especificidade da Espécie , Temperatura , Leveduras/isolamento & purificação
8.
J Immunol ; 189(10): 5057-65, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23071279

RESUMO

Multiple sclerosis (MS) is a demyelinating disease of the CNS that is presumably mediated by CD4(+) autoimmune T cells. Although both Th1 and Th17 cells have the potential to cause inflammatory CNS pathology in rodents, the identity of pathogenic T cells remains unclear in human MS. Given that each Th cell subset preferentially expresses specific chemokine receptors, we were interested to know whether T cells defined by a particular chemokine receptor profile play an active role in the pathogenesis of MS. In this article, we report that CCR2(+)CCR5(+) T cells constitute a unique population selectively enriched in the cerebrospinal fluid of MS patients during relapse but not in patients with other neurologic diseases. After polyclonal stimulation, the CCR2(+)CCR5(+) T cells exhibited a distinct ability to produce matrix metalloproteinase-9 and osteopontin, which are involved in the CNS pathology of MS. Furthermore, after TCR stimulation, the CCR2(+)CCR5(+) T cells showed a higher invasive potential across an in vitro blood-brain barrier model compared with other T cells. Of note, the CCR2(+)CCR5(+) T cells from MS patients in relapse are reactive to myelin basic protein, as assessed by production of IFN-γ. We also demonstrated that the CCR6(-), but not the CCR6(+), population within CCR2(+)CCR5(+) T cells was highly enriched in the cerebrospinal fluid during MS relapse (p < 0.0005) and expressed higher levels of IFN-γ and matrix metalloproteinase-9. Taken together, we propose that autoimmune CCR2(+)CCR5(+)CCR6(-) Th1 cells play a crucial role in the pathogenesis of MS.


Assuntos
Metaloproteinase 9 da Matriz/imunologia , Esclerose Múltipla/imunologia , Osteopontina/imunologia , Receptores CCR2 , Receptores CCR5 , Células Th1/imunologia , Adulto , Idoso , Animais , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Movimento Celular/imunologia , Feminino , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Masculino , Metaloproteinase 9 da Matriz/biossíntese , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Osteopontina/biossíntese , Receptores CCR6 , Células Th1/metabolismo , Células Th1/patologia , Células Th17/imunologia , Células Th17/metabolismo , Células Th17/patologia
9.
J Neuroimmunol ; 236(1-2): 111-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21652010

RESUMO

Interferon-ß (IFN-ß) is known to expand regulatory CD56(bright) natural killer (NK) cells in multiple sclerosis (MS). In this cross-sectional study we show that MS patients treated with IFN-ß alone or in combination with low-dose prednisolone displayed increased proportion of all NK cell subsets in the active phase of the cell cycle (Ki-67+). There was no difference in NK cell apoptosis markers. In vitro experiments showed that both IFN-ß and IFN-ß in combination with corticosteroids increased the proportion of Ki-67(+) NK cells. This study, although limited, shows that treatment with IFN-ß affects NK cell cycle without altering NK cell apoptosis in MS patients.


Assuntos
Interferon beta/administração & dosagem , Antígeno Ki-67/biossíntese , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Prednisolona/administração & dosagem , Administração Oral , Células Cultivadas , Estudos de Coortes , Estudos Transversais , Quimioterapia Combinada , Humanos , Contagem de Linfócitos , Esclerose Múltipla/tratamento farmacológico
10.
J Clin Microbiol ; 49(2): 613-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21159943

RESUMO

Seven body polishers working in the same "hot spa" presented with multiple red nodules and papules on their hands and forearms. A causative agent was successfully isolated from two of the subjects and from a swab sample collected from the underside of a bed cover in the body-polishing facility. The two cutaneous isolates and the environmental isolate were rapidly growing mycobacteria that formed nonphotochromogenic smooth or smooth/rough colonies on Ogawa egg slants. They were identified as Mycobacterium massiliense by multigenotypic analysis using the 16S rRNA, hsp65, and rpoB genes and the 16S-23S rRNA internal transcribed spacer (ITS) region. However, the use of the 16S rRNA gene sequence and/or DNA-DNA hybridization (DDH Mycobacteria Kit) alone would not distinguish M. massiliense from mycobacteria in the M. chelonae-M. abscessus group. The three isolates were significantly more susceptible to clarithromycin, doxycycline, and minocycline than the M. abscessus and M. bolletii reference strains. One cutaneous isolate and the environmental isolate were in a related cluster by randomly amplified polymorphic DNA PCR (RAPD-PCR). Of the several mycobacterial species found in the day spa, only M. massiliense was isolated from biopsy specimens of the skin lesions, suggesting that this bacterium is a human skin pathogen. This is the first known report of cutaneous M. massiliense infections that could not be attributed to a prior invasive procedure. This is also the first report of M. massiliense infection in Japan.


Assuntos
Infecções por Mycobacterium/diagnóstico , Infecções por Mycobacterium/microbiologia , Mycobacterium/isolamento & purificação , Dermatopatias Bacterianas/diagnóstico , Dermatopatias Bacterianas/microbiologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Microbiologia Ambiental , Feminino , Humanos , Japão , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mycobacterium/classificação , Mycobacterium/genética , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Análise de Sequência de DNA
11.
Masui ; 59(6): 757-60, 2010 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-20560383

RESUMO

We report a case of inadvertent arterial misplacement of a large-caliber cannula during jugular vein catheterization. A tip of a 9F cannula was inadvertently placed into the brachiocephalic trunk via the subclavian artery. The arterial trauma was managed by cannula removal and external compression without secondary traumas. Our case emphasizes that the excursion of the subclavian artery is associated with a significant risk of trauma on the subclavian artery during jugular vein catheterization.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Cateterismo/efeitos adversos , Tronco Braquiocefálico/lesões , Cateterismo/métodos , Cateterismo Venoso Central/métodos , Feminino , Humanos , Veias Jugulares , Pessoa de Meia-Idade , Artéria Subclávia/lesões
12.
J Neurol Sci ; 290(1-2): 172-6, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20006850

RESUMO

Pantothenate kinase-associated neurodegeneration (PKAN), formerly known as Hallervorden-Spatz syndrome (HSS), is an autosomal recessive neurodegenerative disorder characterized by iron accumulation in the brain. Mutations in the pantothenate kinase 2 (PANK2) gene are known to be responsible for PKAN. Several studies have revealed correlations between clinical phenotypes and particular PANK2 mutations. The adult-onset slowly progressive type of PKAN with PANK2 mutations is very rare. In this report, we describe siblings with the adult-onset slowly progressive type of PKAN with a novel mutation, Ile346Ser, in PANK2. The siblings had the same mutation in PANK2 and had common clinical signs such as misalignment of teeth, a high arched palate, hollow feet, a slight cognitive decline, and an apparent executive dysfunction, although they showed different patterns of movement disorders. Thus, even if PKAN patients have identical mutations, it is likely that they will present with different types of movement disorders. Brain perfusion single photon emission computed tomography in both patients showed decreased regional cerebral blood flow in the bilateral frontoparietal lobes, the globus pallidus, the striatum, and around the ventriculus quartus. Cardiac uptake of [(123)I] meta-iodobenzylguanidine was normal in both patients. Analysis of genotype-phenotype correlations and the elucidation of mutational effects on pantothenate kinase 2 function, expression, and structure are important for understanding the mechanisms of PKAN.


Assuntos
Encéfalo/fisiopatologia , Predisposição Genética para Doença/genética , Mutação/genética , Neurodegeneração Associada a Pantotenato-Quinase/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Irmãos , Idade de Início , Substituição de Aminoácidos/genética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Circulação Cerebrovascular/genética , Análise Mutacional de DNA , Progressão da Doença , Feminino , Testes Genéticos , Genótipo , Glicopeptídeos , Humanos , Isoleucina/genética , Masculino , Pessoa de Meia-Idade , Compostos de Organotecnécio , Neurodegeneração Associada a Pantotenato-Quinase/diagnóstico por imagem , Neurodegeneração Associada a Pantotenato-Quinase/patologia , Serina/genética , Tomografia Computadorizada de Emissão de Fóton Único
15.
Phytochemistry ; 66(13): 1607-13, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16005311

RESUMO

The components involved in the formation of protocyanin, a stable blue complex pigment from the blue cornflower, Centaurea cyanus, were investigated. Reconstruction experiments using highly purified anthocyanin [centaurocyanin, cyanidin 3-O-(6-O-succinylglucoside)-5-O-glucoside], flavone glycoside [apigenin 7-O-glucuronide-4'-O-(6-O-malonylglucoside)] and metals, Fe and Mg, showed the presence of another factor essential for the formation of protocyanin. The unknown factor was revealed to be Ca. Reconstructed protocyanin using anthocyanin, flavone, Fe, Mg, and Ca was identical with protocyanin from nature in UV-Vis and CD spectra, and was isolated as crystals for the first time. In addition, substitution of the metal components in protocyanin with other metals was also examined.


Assuntos
Antocianinas/química , Centaurea/química , Flores/química , Glicosídeos/química , Pigmentos Biológicos/química , Antocianinas/isolamento & purificação , Cristalografia por Raios X , Glicosídeos/isolamento & purificação , Metais/química , Modelos Moleculares , Estrutura Molecular , Pigmentos Biológicos/isolamento & purificação , Espectrofotometria
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