Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Chemistry ; 7(23): 5011-28, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11775675

RESUMO

Reaction of the dinuclear M(II)-bis(mu-hydroxo) complexes of nickel and cobalt, [(M(II)(TpR)]2(mu-OH)2] (M = Ni; 3Ni M = Co: 3Co), with one equivalent of H2O2 yields the corresponding M(III)-bis(mu-oxo) complexes, [[M(III)(TpR)]2-(mu-O)2] (M=Ni; 2Ni, M=Co: 2Co). The employment of a series of TpMe2,X (TpMe2,X = hydrotris(3,5-dimethyl-4-X-1-pyrazolyl)borate; X = Me, H, Br) as a metal supporting ligand makes it possible to isolate and structurally characterize the thermally unstable M(III)-bis-(mu-oxo) complexes 2Ni and 2Co. Both the starting (3Ni and 3Co) and resulting complexes (2Ni and 2Co) contain five-coordinate metal centers with a slightly distorted square-pyramidal geometry. Characteristic features of the nickel complexes 2Ni, such as the two intense absorptions around 400 and 300 nm in the UV-visible spectra and the apparent diamagnetism, are very similar to those of the previously reported bis(mu-oxo) species of Cu(III) and Ni(III) with ligands other than TpR, whereas the spectroscopic properties of the cobalt complexes 2Co (i.e., paramagnetically shifted NMR signals and a single intense absorption appearing at 350 nm) are clearly distinct from those of the isostructural nickel compounds 2Ni. Thermal decomposition of 2Ni and 2Co results in oxidation of the inner saturated hydrocarbyl substituents of the TpR ligand. Large kH/kD values obtained from the first-order decomposition rates of the TpMe3 and Tp(CD3)2,Me derivatives of 2 evidently indicate that the rate-determining step is an hydrogen abstraction from the primary C-H bond of the methyl substituents. mediated by the M(III)2-(mu-O)2 species. The nickel complex 2Ni shows reactivity about 10(3) times greater than that of the cobalt analogue 2Co. The oxidation ability of the M(III)(mu-O)2M(III) core should be affected by the hindered TpR ligand system, which can stabilize the +2 oxidation state of the metal centers.


Assuntos
Cobalto/química , Níquel/química , Compostos Organometálicos/química , Oxigênio/metabolismo , Cristalografia por Raios X , Ligantes , Metaloproteínas/química , Estrutura Molecular , Oxirredução , Análise Espectral
2.
No To Hattatsu ; 30(6): 500-4, 1998 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-9844414

RESUMO

Single photon emission computed tomography (SPECT) is a tool to study cerebral blood flow (CBF) kinetics. There are three methods of evaluating SPECT images: visual, semi-quantitative (evaluation of the radioactivity ratio of the cerebral region to the cerebellum [R/CE] or to the thalamus [R/TH]) and quantitative (Matsuda's method by Patlak plot method using 99m Tc-hexamethylpropylene amine oxime radionuclide angiography). We evaluated SPECT images by the quantitative method in 14 patients with neurological disorders and examined the correlation of the results to those obtained by the semi-quantitative method. There was no significant correlation between the R/CE or R/TH ratio and regional CBF except two regions. The evaluation by the semi-quantitative method may have been inappropriate, probably because the cerebellar or thalamic blood flow was not constant in each case. Evaluation by the quantitative method, on the other hand, seemed to be useful not only for the comparison of CBF among normal subjects, but also in the demonstration of progressive changes of CBF in the same case. The Matsuda's method by the Patlak plot method is suitable for examination of children, since it dose not require aortic blood sampling.


Assuntos
Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adolescente , Adulto , Doenças do Sistema Nervoso Central/diagnóstico por imagem , Doenças do Sistema Nervoso Central/fisiopatologia , Criança , Feminino , Humanos , Masculino , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Exametazima
3.
Nihon Ishinkin Gakkai Zasshi ; 39(1): 11-6, 1998.
Artigo em Japonês | MEDLINE | ID: mdl-9487003

RESUMO

Topical treatment with an antifungal agent was performed in 70 cases of onychomycosis (69 cases of tinea unguium and 1 case of Candida onychomycosis). The patients were treated every night by occlusive dressing using bifonazole cream containing 40% urea, and then by simple application of 1% bifonazole solution in the morning. During the treatment period, the softened affected nails were removed as completely as possible with nail clippers and files. The nails were observed every two weeks, and the efficacy was evaluated after 12 weeks. Two cases were excluded and 28 cases dropped out leaving 40 cases for efficacy evaluation. Among the 40 patients, 20 appeared to be mycologically negative (mycological cure rate: 50.0%). Clinical response was judged by the changes in opacity and thickness of the nails. Nine patients were evaluated as showing "marked improvement" and 16 as showing "improvement" (improvement rate: 62.5%). Erosion was noted as an adverse reaction in 2 patients. In one patient, treatment was stopped and the lesion was improved by antibiotic ointment, and in another, treatment was resumed when erosion was cured by discontinuation of the treatment. These results suggest that the topical treatment of onychomycosis by occlusive dressing is a useful method for those patients who have difficulties in or do not wish to be treated with oral antifungal agents.


Assuntos
Antifúngicos/administração & dosagem , Candidíase/tratamento farmacológico , Imidazóis/administração & dosagem , Curativos Oclusivos , Onicomicose/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Onicomicose/microbiologia , Ureia/administração & dosagem
4.
No To Hattatsu ; 28(6): 515-9, 1996 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-8940879

RESUMO

Dizziness in childhood is not an infrequent symptom, but epileptic vertigo is a rare condition in children. Here we report an 8-year-old Japanese boy with epileptic vertiginous seizures. At age 8 years, he visited Nippon Medical School Hospital because of a ten day history of dizziness. The dizziness occurred more than twenty times a day and he was hospitalized. On physical examination, the patient appeared normal and there were no abnormal neurological findings, including eye movement and cerebellar signs. Ophthalmoscopy, otoscopy, vestibular function test and hearing test were normal. Computerized tomography scanning and MR imaging of the head revealed no significant abnormality. The dizziness observed on admission comprised sudden brief attacks of rotatory sensation without amnesia regarding the event. Sometimes the attacks were accompanied by tremor like movement and numbness of the right hand, followed by postictal unsteadiness. Interictal EEG revealed spike-and-wave complexes in the central region dominantly in the light sleep stage. On ictal EEG, seizure discharges were observed to begin in the left central region and they increased in amplitude and subsequently propagated to the frontal and occipital regions. These findings were most suggestive of partial seizures. The patient was treated with carbamazepine and the seizures became well under control.


Assuntos
Epilepsia do Lobo Frontal/complicações , Vertigem/etiologia , Anticonvulsivantes/uso terapêutico , Carbamazepina/uso terapêutico , Criança , Eletroencefalografia , Epilepsia do Lobo Frontal/diagnóstico , Epilepsia do Lobo Frontal/tratamento farmacológico , Humanos , Masculino , Vertigem/diagnóstico , Vertigem/tratamento farmacológico
5.
Infect Immun ; 64(8): 2936-40, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8757816

RESUMO

An extracellular esterase from Candida albicans A-714 was found to be induced in a medium containing 0.7% yeast nitrogen base and 2.5% Tween 80 (polyoxyethylenesorbitan compounds). Enzyme activity, which exists predominantly in the extracellular space, was measured by a colorimetric method using alpha-naphthyl palmitate as a substrate. The induction level of the esterase activity was found to be well correlated with fungal growth and was dependent on the Tween 80 concentration. Such esterase activity was observed only in medium containing Tween 80 or other Tweens as the sole carbon source and therefore was not observed in either peptone-glucose medium or peptone-glucose medium supplemented with Tween 80. The induced esterase was heat labile and had maximum activity at pH 5.5. Enzyme activity was stimulated by the addition of sodium taurocholate, an activator of lipase. Thin-layer chromatography revealed that this enzyme does not hydrolyze triolein and L-alpha-lecithin, suggesting that it is a monoester hydrolase (not a lipase in the strict sense of the word). Esterase activity was examined in 85 clinical isolates of Candida species; C. albicans, C. tropicalis, and C. parapsilosis tended to have higher enzyme activities than C. kefyr, C. krusei, C. glabrata, and C. guilliermondii. Although the physiological properties of this esterase are not clear at present, it was found to be crucial for fungal growth under specific conditions.


Assuntos
Candida albicans/enzimologia , Esterases/biossíntese , Regulação Fúngica da Expressão Gênica , Indução Enzimática , Especificidade da Espécie
6.
Brain Dev ; 17(6): 425-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8747421

RESUMO

A clinico-neuropathological study of a Japanese girl with hypomelanosis of Ito, one of the neurocutaneous syndromes, is reported. At birth, typical skin hypopigmentation on the trunk and a hypopigmented streak on the left lower extremity were noted. From 2 months of age, intractable convulsions occurred and EEG showed various abnormalities. Psychomotor development was severely retarded and she died of pneumonia at the age of 13 months. Neuropathological examination revealed brachycephaly, micropolygyria and asymmetry of lateral ventricles. A histological examination showed a disarray of cortical lamination, and the existence of nerve cells in the white matter. These pathological findings showed a migration anomaly during brain maturation.


Assuntos
Transtornos da Pigmentação/patologia , Autopsia , Encéfalo/patologia , Movimento Celular/fisiologia , Evolução Fatal , Feminino , Humanos , Lactente , Neurônios/patologia , Transtornos da Pigmentação/complicações , Convulsões/etiologia
7.
Mycopathologia ; 123(2): 69-73, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8264769

RESUMO

Sporothrix schenckii produces two extracellular proteinases, namely proteinase I and II. Proteinase I is a serine proteinase, inhibited by chymostatin, while proteinase II is an aspartic proteinase, inhibited by pepstatin. Studies on substrate specificity and the effect of proteinase inhibitors on cell growth suggest an important role for these proteinases in terms of fungal invasion and growth. There has, however, been no evidence presented demonstrating that S. schenckii produces 2 extracellular proteinases in vivo. In order to substantiate the in vivo production of proteinases and to attempt a preliminary serodiagnosis of sporotrichosis, serum antibodies against 2 proteinases were assayed using S. schenckii inoculated hairless mice. Subsequent to an intracutaneous injection of S. schenckii to the mouse skin, nodules spontaneously formed and disappeared for a period of 4 weeks. Histopathological examination results were in accordance with the microscopic observations. Micro-organisms disappeared during the fourth week. Serum antibody titers against purified proteinases I and II were measured weekly, using enzyme-linked immunosorbent assay (EIA). As a result, the time course of the antibody titers to both proteinases I and II were parallel to that of macroscopic and microscopic observations in an experimental mouse sporotrichosis model. These results suggest that S. schenckii produces both proteinases I and II in vivo. Moreover, the detection of antibodies against these proteinases can contribute to a serodiagnosis of sporotrichosis.


Assuntos
Anticorpos Antifúngicos/sangue , Endopeptidases/imunologia , Sporothrix/imunologia , Esporotricose/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Pelados , Camundongos Endogâmicos ICR , Testes Sorológicos , Testes Cutâneos , Sporothrix/enzimologia , Esporotricose/diagnóstico , Esporotricose/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...