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1.
Haemophilia ; 20(2): 255-62, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24286209

RESUMO

Factor XIII (FXIII) consists of the A and B subunits (FXIII-A and FXIII-B) and stabilizes fibrin clots. Defects in either the FXIII-A or FXIII-B gene lead to congenital FXIII deficiency, which manifests a life-long haemorrhagic tendency. Thus, prophylactic FXIII replacement therapy is recommended. To establish a management plan for a 30-year-old male patient with 'indefinite' FXIII deficiency (<40% of the normal FXIII), he was characterized by state-of-the-art techniques as guided by the FXIII/Fibrinogen subcommittee of ISTH/SSC. FXIII activity turned out to be virtually undetectable by three functional assays. Four immunological assays detected essentially no FXIII protein, FXIII-A antigen, and A2 B2 antigen, but normal FXIII-B antigen. Accordingly, he was diagnosed as a 'severe' FXIII-A deficiency case. He had no anti-FXIII antibodies, because a 1:1 cross-mixing test (ammonia release assay) and a five-step mixing test (amine incorporation assay) between his plasma and normal plasma demonstrated deficiency patterns. Furthermore, a dosing test using plasma-derived FXIII concentrates revealed its normal recovery. DNA sequencing analysis identified two novel mutations, W187X & G273V, in the F13A gene. Genetic analyses confirmed that he was a compound heterozygote and his mother and sister were heterozygotes of either one of these mutations, indicating the hereditary nature of this disorder. Molecular modelling predicted that the G273V mutation would cause clashes with the surrounding residues in the core domain of FXIII-A, and ultimately would result in the instability of the mutant molecule. Detailed characterization of 'indefinite' FXIII deficiency made it possible to make its definite diagnosis and best management plan.


Assuntos
Deficiência do Fator XIII/diagnóstico , Deficiência do Fator XIII/genética , Fator XIII/genética , Mutação , Adulto , Sequência de Aminoácidos , Substituição de Aminoácidos , Códon , Fator XIII/química , Fator XIII/imunologia , Fator XIII/metabolismo , Heterozigoto , Humanos , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Guias de Prática Clínica como Assunto , Conformação Proteica , Alinhamento de Sequência , Índice de Gravidade de Doença
2.
AJNR Am J Neuroradiol ; 28(4): 622-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17416810

RESUMO

BACKGROUND AND PURPOSE: The role of blood-flow biomechanics on the size, morphology, and growth of cerebral aneurysms is poorly known. The purpose of this study was to evaluate intra-aneurysmal hemodynamics before and after aneurysm growth. MATERIALS AND METHODS: A flow-simulation study was performed in a middle cerebral artery (MCA) aneurysm with a bleb that grew after 1-year follow-up. Geometrically realistic in vitro models before and after aneurysm growth were constructed on the basis of CT angiograms. Blood-flow velocity, vorticity, and wall shear stress were obtained by using particle imaging velocimetry and laser Doppler velocimetry. RESULTS: No significant quantitative differences were noted among the overall flow structures before and after aneurysm growth, with the exception of less vorticity in the bleb after aneurysm growth. A circulating flow pattern was seen within the aneurysm domes. A blood-flow separation was observed at the margins of the bleb. No impingement of inward flow into the enlarging bleb was noted. Before the aneurysm growth, the wall shear stress was high at the aneurysm neck and also at the margin of the bleb. The value of wall shear stress decreased in the deeper part of the bleb. This value decreased even more after the aneurysm growth. CONCLUSIONS: Intra-aneurysmal hemodynamic structures before and after the growth of an MCA aneurysm were compared. Further investigation with a similar approach is mandatory to obtain a firm conclusion.


Assuntos
Velocidade do Fluxo Sanguíneo , Angiografia Cerebral , Aneurisma Intracraniano/fisiopatologia , Tomografia Computadorizada Espiral , Tomografia Computadorizada por Raios X , Adulto , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/fisiopatologia , Simulação por Computador , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia , Modelos Cardiovasculares , Resistência ao Cisalhamento
3.
Arch Environ Contam Toxicol ; 48(2): 209-16, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15696346

RESUMO

Endocrine-disrupting chemicals with estrogenic activity (e.g., alkylphenols) have been detected in coastal Japan. We aimed to determine estrogenic activity in extracts of river water, seawater, sediments, and sediment cores from Tokyo Bay by in vitro gene expression assay. Fifty-one of 57 extracts had some estrogenic activity. E2 equivalents (ng E2 equivalents per gram dry weight or per liter above the limit of detection) in river water samples ranged from 0.70 to 4.01 ng/L; in seawater samples from 0.34 to 2.52 ng/L; and in surface sediments from 2.07 to 12.1 ng/g. The relationship between salinity and estrogenic activity in water samples suggested that fresh water is one source of environmental estrogens in Tokyo Bay. Fractionation of sediment extracts showed that the highest estrogenic activity was observed in the midpolar fraction. The observed activities were compared with activities mediated by known concentrations of nonylphenol, bisphenol-A, estrone, and 17beta-estradiol. In sediment collected near the sewage treatment plants, the estrogenic activity of the midpolar fraction could be explained about 34% by nonylphenol and estrone contained in this fraction. Core sediment measurements detected estrogenic activity from as far back as the 1960s. The regulations on the industrial wastewater in early 1970s would be one of the main reasons for the lower estrogenic activity in the upper section of the sediment core. The high estrogenic activities as measured in water and sediment samples from Tokyo might be restricted to certain coastal areas.


Assuntos
Estrogênios/análise , Estrogênios/toxicidade , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Bioensaio , Neoplasias da Mama/patologia , Monitoramento Ambiental , Perfilação da Expressão Gênica , Humanos , Resíduos Industriais , Japão , Células Tumorais Cultivadas , Eliminação de Resíduos Líquidos
4.
Appl Microbiol Biotechnol ; 62(2-3): 274-8, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12883875

RESUMO

Feasibility of biological mercury removal from wastewater was examined by using alginate-immobilized cells of Escherichia coli carrying mer-ppk fusion plasmid pMKB18. Immobilized cells engineered to express mercury-transport system, organomercurial lyase and polyphosphate efficiently removed organic and inorganic mercury from contaminated wastewater over a wide concentration range of mercurials, probably via intracellular accumulation mediated by ppk-specified polyphosphate. Bioaccumulation of mercury was selective compared to other metals such as Cd(2+), Pb(2+) and Cr(6+). The immobilized cells could be used repeatedly (at least three times) without large loss of mercury removal activity. From these results, it is concluded that the mer-ppk fusion plasmid and the immobilized cells are useful for simultaneous removal of organic and inorganic mercury from contaminated wastewater.


Assuntos
Escherichia coli/genética , Escherichia coli/metabolismo , Compostos de Mercúrio/isolamento & purificação , Compostos Organomercúricos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Fusão Gênica Artificial , Células Imobilizadas , Enterobacter aerogenes/genética , Genes Bacterianos , Compostos de Mercúrio/metabolismo , Modelos Biológicos , Compostos Organomercúricos/metabolismo , Fosfotransferases (Aceptor do Grupo Fosfato)/genética , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , Plasmídeos/genética , Pseudomonas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Poluentes Químicos da Água/metabolismo
5.
Eur J Haematol ; 67(1): 45-50, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11553266

RESUMO

Hepatitis virus infection through virus reactivation has a high risk of mortality in patients with hematological malignancies receiving chemotherapy. We examined the incidence of both hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and severe liver dysfunction (alanine aminotransferase >ten times the normal upper limit and total bilirubin >5 mg/dl) during chemotherapy in 268 patients with hematological malignancies. Eight patients (3.0%) were infected with HBV and 22 patients (8.2%) were infected with HCV. One patient (0.4%) was infected with both HBV and HCV. HBV- or HCV-infected patients showed severe liver dysfunction at a significantly higher incidence than non-infected patients (11/31 (35.5%) vs. 0/237 (0%), p<0.0001). Furthermore, the incidence of severe liver dysfunction in HBV-infected patients was significantly higher than in HCV-infected patients (6/8 (75.0%) vs. 4/22 (18.2%), p<0.01). Three of eight HBV-infected patients were initially negative for hepatitis B surface antigen (HBsAg) by latex agglutination and became positive for HBsAg during chemotherapy. Furthermore, all three patients developed severe liver dysfunction and two developed fatal fulminant hepatitis. From an examination of the original stock of serum samples before chemotherapy, two patients were found to be positive for HBV-DNA by polymerase chain reaction (PCR). Although post-transfusion HBV infection was suspected in the one remaining patient, the cause of HBV infection could not be clarified due to the impossibility of examination in blood donors. Since HBV-infected patients develop severe liver dysfunction at a higher incidence than either patients not infected with virus or HCV-infected patients before chemotherapy for hematological malignancies, it is recommended that HBV-DNA should be tested by PCR to detect HBV marker-negative carriers and liver function tests should be carefully monitored.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Hematológicas/tratamento farmacológico , Hepacivirus/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Fígado/fisiopatologia , Ativação Viral/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , DNA Viral/sangue , Feminino , Neoplasias Hematológicas/complicações , Hepacivirus/fisiologia , Hepatite B/complicações , Hepatite B/fisiopatologia , Hepatite B/transmissão , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/fisiologia , Hepatite C/complicações , Hepatite C/fisiopatologia , Humanos , Incidência , Japão/epidemiologia , Falência Hepática/etiologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Reação Transfusional
6.
Int J Hematol ; 73(1): 115-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11372746

RESUMO

We report a case of a 41-year-old man with acute myelogenous leukemia who developed fulminant hepatitis from reactivation of trace hepatitis B virus (HBV) 2 months after complete remission. Although he became positive for HB surface antigen at the onset of fulminant hepatitis, he had been negative for HBV serum markers, and only HBV DNA was detected by polymerase chain reaction (PCR) amplification on admission. The original stocks of serum samples from all blood donors were tested again for HBV DNA by PCR, and all samples were negative. This case demonstrates that testing for HBV DNA by PCR is necessary before chemotherapy, because silent HBV carriers are rare and fulminant hepatitis may be induced by chemotherapy in patients with hematologic malignancies.


Assuntos
Antineoplásicos/efeitos adversos , Hepatite B/etiologia , Leucemia Mieloide Aguda/complicações , Falência Hepática/virologia , Adulto , DNA Viral/sangue , Hepatite B/induzido quimicamente , Vírus da Hepatite B/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Humanos , Terapia de Imunossupressão/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Reação em Cadeia da Polimerase , Ativação Viral/efeitos dos fármacos
7.
Phytochemistry ; 56(7): 697-701, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11314955

RESUMO

3-Demethyl-14alpha-hydroxyisotylocrebrine N-oxide was isolated along with three homologous isotylocrebrine type alkaloids from the imagines and pupae of Ideopsis similis reared on the host plant, Tylophora tanakae.


Assuntos
Alcaloides/análise , Ração Animal , Asteraceae , Borboletas/fisiologia , Indolizinas/análise , Fenantrenos/análise , Alcaloides/química , Animais , Borboletas/química , Indolizinas/química , Estrutura Molecular , Fenantrenos/química , Pupa , Espectrometria de Massas de Bombardeamento Rápido de Átomos
8.
Z Naturforsch C J Biosci ; 56(11-12): 1126-34, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11837668

RESUMO

Adults, particularly males, of a papilionid butterfly, Papilio machaon hippocrates, emit a fairly strong scent perceivable by humans. We have identified a variety of volatile compounds (hydrocarbons, alcohols, aldehydes, ketones, esters, and so on) from the wings and bodies of both sexes of the butterfly. Male wings secreted n-dodecane, linalool and geranylacetone as major components together with small amounts of camphene, limonene, p-cymene, 2-phenylethanol, n-hexanal, n-decanal, isoamyl acetate, p-allylanisole, 2-pyrrolidone and other characteristic volatiles. The overall profile of volatile compounds detected from male body was quite different from that of the wings. Male body was devoid of camphene, 2-phenylethanol, n-hexanal but instead contained limonene, acetoin, a sesquiterpene hydrocarbon (C15H24, methyl n-octanoate, (E,E)-hepta-2,4-dienal, and another isomer of heptadienal as principal components, of which the last four compounds were specific to the body. All these substances seem to concurrently characterize the male odor. The chemical patterns of compounds found from female wings and body were essentially the same in quality as those of male wings and body, respectively, although their quantities in females were generally smaller than in males. Females, however, had a larger amount of acetamide than males. The chemical compositions of volatiles from the fore and hind wings of males were not greatly different from each other, and every component was considered to be present on all parts of the wings. This suggests that the scent-producing organs or scent-emitting pores are widely distributed on the whole wings. EAG responses of both sexes to 12 selected compounds identified from the butterfly were not strong at a dose of 1 microg, while both sexes showed relatively stronger responses to n-nonanal, methyl n-octanoate, D-limonene and linalool at a higher dose (10 microg). Although sexual difference in EAG response was not prominent, females appeared a little more sensitive, and n-nonanal and acetoin evoked significantly higher responses from females at 1 microg.


Assuntos
Borboletas/fisiologia , Odorantes/análise , Acetamidas/análise , Aldeídos/análise , Animais , Borboletas/crescimento & desenvolvimento , Cromatografia Gasosa , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Óleos Voláteis/análise , Caracteres Sexuais , Asas de Animais/química
9.
Hematology ; 5(6): 429-34, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-27419345

RESUMO

In order to confirm the effect of interferon-α (IFN-α) in inducing a prolonged duration of the chronic phase (CP) on patients with chronic myelogenous leukemia (CML), we retrospectively compared the duration of CP between patients who continued on IFN-α and the patients in whom IFN-α was discontinued before the blast phase. Of the 32 patients not pretreated for CML in the early CP who received IFN-α therapy, 25 continued on IFN-α while seven discontinued the therapy (side effects, 5; resistance, 1; patient's refusal, 1). Only four of the 25 patients in whom IFN-α was continued (16.0%) progressed to the blast phase or accelerated phase, but six of the seven patients who discontinued IFN-α (85.7%) progressed to the blast phase or accelerated phase. Fourteen of the 25 patients who continued on IFN-α therapy showed cytogenetic response (complete cytogenetic response, 3; minimal cytogenetic response, 11) whereas 11 patients showed no cytogenetic response. However, non-responders showed a longer duration of CP than the patients whom IFN-α was discontinued. Although elderly patients showed a high incidence of side effects, and some patients progressed early after the beginning of IFN-α therapy, our data clearly demonstrated that in accordance with previous large multi-centric randomized studies the continuation of IFN-α, even in low doses, prevents disease progression.

10.
Int J Hematol ; 72(2): 186-93, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11039667

RESUMO

c-Kit is expressed in hematopoietic stem cells and plays an important role in hematopoiesis. In 16 patients with malignancies, serum-soluble c-Kit levels and the expressions of c-KIT messenger RNA (mRNA) and protein in peripheral blood mononuclear cells were analyzed serially during 26 courses of peripheral blood stem cell (PBSC) mobilization after granulocyte colony-stimulating factor administration following chemotherapy for PBSC harvest. Serum-soluble c-Kit levels were significantly lower in patients than in controls (179.7+/-17.7 arbitrary units [AU]/mL versus 274.5+/-18.9 AU/mL; P < .001), decreasing after chemotherapy (167.7+/-18.2 AU/mL), increasing from day 14, and peaking at day 19 (193.3+/-16.4 AU/mL). The numbers of both c-Kit+ cells and CD34+ cells and granulocyte-macrophage colony-forming units in peripheral blood peaked at day 17, following the peak of the expression of c-KIT mRNA. Serum-soluble c-Kit levels showed a significant positive correlation with the numbers of CD34+ cells in both peripheral blood and leukapheresis products (r = 0.553, P < .01, and r = 0.640, P < .001, respectively) and changed at higher levels in patients with large numbers of PBSCs versus patients with small numbers of PBSCs (P < .05). Serum-soluble c-Kit may reflect the capacity for hematopoiesis after chemotherapy and may be useful in predicting the number of PBSCs that can be mobilized and harvested after mobilization, as well as for monitoring the timing for PBSC harvest.


Assuntos
Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Proteínas Proto-Oncogênicas c-kit/sangue , Proteínas Proto-Oncogênicas c-kit/farmacologia , Adulto , Idoso , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/terapia , Linfoma não Hodgkin/sangue , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Mieloma Múltiplo/terapia , Proteínas Proto-Oncogênicas c-kit/fisiologia , Neoplasias Testiculares/sangue , Neoplasias Testiculares/terapia
11.
Anticancer Res ; 20(1A): 251-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10769663

RESUMO

To explore their potential use as in vivo tracers, the uptake of the amino acids glutamine, glutamate and aspartate, labeled with 11C or 14C, was evaluated in tumor cell aggregates, in vivo in rats and a few pilot studies with positron emission tomography (PET) in patients. The uptake in aggregates increased linearly with time, and was competitively inhibited by the same amino acids. The uptake of 14C-glutamate in carcinoid cells (BON) was inhibited by cystine but not by aspartate, contrary to the result in neuroblastoma (LAN). 6-Diazo-oxy-L-norleucine (a glutamine analogue) and Substance P had different effect on the uptake of glutamate in different cells. The metabolic fate of 14C-glutamate was evaluated with protein separation and with HPLC. The in vivo distribution in rats showed the highest uptake of 11C-glutamine and 11C-glutamate in pancreas and kidney, and of 11C-aspartate in the lung. In the human studies with PET, pancreas had the highest uptake followed by kidney with 11C-glutamate, and followed by spleen with 11C-aspartate. A primary pancreas tumour and metastases in liver were difficult to identify except in one case.


Assuntos
Ácido Aspártico/farmacocinética , Radioisótopos de Carbono/farmacocinética , Ácido Glutâmico/farmacocinética , Glutamina/farmacocinética , Tumores Neuroendócrinos/metabolismo , Tomografia Computadorizada de Emissão , Ácido 2-Aminoadípico/farmacologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/secundário , Animais , Ácido Aspártico/metabolismo , Transporte Biológico/efeitos dos fármacos , Radioisótopos de Carbono/metabolismo , Tumor Carcinoide/diagnóstico por imagem , Tumor Carcinoide/prevenção & controle , Agregação Celular , Cromatografia Líquida de Alta Pressão , Diazo-Oxo-Norleucina/farmacologia , Glioma/metabolismo , Glioma/patologia , Ácido Glutâmico/metabolismo , Glutamina/antagonistas & inibidores , Glutamina/metabolismo , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Masculino , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia , Octreotida/farmacologia , Neoplasias Pancreáticas/diagnóstico por imagem , Projetos Piloto , Traçadores Radioativos , Ratos , Ratos Sprague-Dawley , Substância P/farmacologia , Distribuição Tecidual , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
12.
J Biosci Bioeng ; 89(4): 350-60, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-16232758

RESUMO

A thermophilic bacterium, Streptomyces sp. IKD472, that can oxidize xylitol was isolated from a hot spring and was found to produce xylitol oxidase. The purified enzyme was a monomeric protein with an apparent molecular weight of 43 k as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration. This novel enzyme is capable of catalyzing the oxidation of one mole of xylitol to form one mole each of xylose and hydrogen peroxide. Since the V(max)K(m) value for xylitol was two and four times higher than those for galactitol and n-sorbitol, respectively, the enzyme was designated as xylitol oxidase. The enzyme was stable in the pH range from 5.5 to 10.5 and at temperatures up to 65 degrees C. The optimal temperature and pH were 55 degrees C and pH 7.5, respectively. Xylitol oxidase bound one mole of FAD as a coenzyme per mole of protein. The amino acid sequence of the NH2 terminus and the fragments obtained by lysylendpeptidase digestion of xylitol oxidase were determined for preparation of synthetic oligonucleotides as hybridization probes. A 2.8-kb chromosomal fragment hybridizing to the probes was cloned into pUC18 in Escherichia coli. The gene consists of an open reading frame of 1245 by that encodes a protein containing 415 amino acids with a molecular weight of 44,730 but without the conserved nucleotide-binding sequence, Gly-X-Gly-X-X-Gly. The amino acid sequence has 70% identity to putative oxidoreductase from Streptomyces coelicolar, 51% to sorbitol oxidase from Streptomyces sp., and 26% to L-gulonolactone oxidase from rat in terms of the overall amino acid sequence. DNA manipulation of the cloned gene in E. coli, by alteration of a strong promoter and a synthesized ribosome-binding sequence at an appropriate position, resulted in overproduction of xylitol oxidase 100 times more than that produced in the original Streptomyces sp. IKD472. The enzyme properties of recombinant xylitol oxidase were the same as those of the authentic enzyme. Stable xylitol oxidases, which allow easier quantitative analysis of xylitol, are useful for clinical applications.

13.
Appl Radiat Isot ; 50(6): 1025-32, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10391715

RESUMO

An enzymatic synthesis of nca 6-[18F]fluoro-L-dopa has been developed. The process consists of a chemical synthesis of 4-[18F]fluorocatechol and its enzymatic reaction with beta-tyrosinase. The 4-[18F]fluorocatechol was prepared by nucleophilic aromatic substitution of the NO2 group on 6-nitroveratoraldehyde with [K/222]+18F-, followed by decarbonylation with tris(triphenylphosphine) rhodium(I) chloride and hydrolysis with hydroiodic acid. By C18 Sep-Pak purification, 4-[18F]fluorocatechol was obtained in ethanol with a radiochemical yield of 9.2%. An enzymatic reaction of 4-[18F]fluorocatechol, ammonium and pyruvate catalyzed by beta-tyrosinase in an ethanolic Tris-HCl buffer (pH 9.0) containing ascorbate gave within 5 min 6-[18F]fluoro-L-dopa with an approximate radiochemical yield of 60% without any isomers. The deproteinized reaction mixture was applied to a preparative reverse phase column, and the radiochemically and enantiomerically pure 6-[18F]fluoro-L-dopa was obtained with a radiochemical yield of 2.0% based on [18F]F- (decay-corrected). The synthesis time was 150 min from the EOB and the specific activity was > 200 GBq/micromol.


Assuntos
Di-Hidroxifenilalanina/análogos & derivados , Radioisótopos de Flúor , Compostos Radiofarmacêuticos/síntese química , Tirosina Fenol-Liase , Cromatografia Líquida de Alta Pressão , Di-Hidroxifenilalanina/síntese química , Indicadores e Reagentes , Isomerismo , Cinética , Estrutura Molecular
14.
Eur J Biochem ; 253(2): 480-4, 1998 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9654100

RESUMO

Inducible pyrrole-2-carboxylate decarboxylase, which catalyzes the decarboxylation of pyrrole-2-carboxylate to pyrrole and CO2 in stoichiometric amounts, was purified from Bacillus megaterium PYR2910. The purity of the enzyme was shown by SDS/PAGE and gel-permeation HLPC. The enzyme has a molecular mass of approximately 98 kDa and consists of two identical subunits. It is highly specific for pyrrole-2-carboxylate, and also catalyzes the reverse reaction, the carboxylation of pyrrole. A unique feature of this enzyme is its requirement of an organic acid, such as acetate, propionate, butyrate or pimelate. A possible catalytic mechanism including a cofactor function of organic acid is discussed.


Assuntos
Bacillus megaterium/enzimologia , Proteínas de Bactérias/isolamento & purificação , Carboxiliases/isolamento & purificação , Acetatos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Carboxiliases/química , Carboxiliases/metabolismo , Concentração de Íons de Hidrogênio , Nitrato de Prata/farmacologia , Especificidade por Substrato
15.
Am J Gastroenterol ; 93(1): 122-3, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9448193

RESUMO

We report a patient with chronic active hepatitis C developing acute anosmia during interferon (IFN) therapy. On July 31, he began receiving 6 MU of IFN-alpha daily. On September 26, he failed to smell gas leaking from a gas cooker, so IFN therapy was discontinued. He showed no reaction on a standard olfactory acuity test. As the patient had borderline diabetes, the association of anosmia with impaired glucose tolerance cannot completely be excluded, but his anosmia was probably induced by IFN therapy, since anosmia developed 10 days after the initiation of the IFN therapy, without any deterioration of his glucose intolerance.


Assuntos
Antivirais/efeitos adversos , Hepatite C Crônica/terapia , Interferon-alfa/efeitos adversos , Transtornos do Olfato/induzido quimicamente , Antivirais/administração & dosagem , Glicemia/análise , Teste de Tolerância a Glucose , Humanos , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Transtornos do Olfato/diagnóstico , Fatores de Tempo
16.
Nucl Med Biol ; 24(6): 595-601, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9316090

RESUMO

L-2,4-Diamino[4-11C]butyric acid (DAB) was synthesized by an enzyme catalysed carrier added (0.1 micromol KCN) reaction of hydrogen [11C]cyanide with O-acetyl-L-serine followed by reduction. L-[11C]DAB was obtained with a radiochemical purity higher than 96% and with a decay corrected radiochemical yield of 30-40% within a 32 min reaction time. The enantiomeric excess was 98%. The uptake of L-[11C]DAB was investigated in multicellular aggregates of six different cell lines and animal tumour models. L-[11C]DAB is potentially useful for the assessment of pharmacokinetics of L-DAB in vivo for part of its evaluation as an antitumoural agent, although its use for diagnostic purposes seems limited.


Assuntos
Aminobutiratos , Radioisótopos de Carbono , Neoplasias Experimentais/diagnóstico por imagem , Aminobutiratos/farmacocinética , Animais , Autorradiografia , Ratos , Distribuição Tecidual , Tomografia Computadorizada de Emissão , Células Tumorais Cultivadas
18.
Mutat Res ; 354(1): 15-26, 1996 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-8692202

RESUMO

Two immortal fibroblastic cell strains (substrains) were established by culturing healthy skin cells obtained from a high-dose atomic bomb survivor (female, age 76 years, 5.14 Gy) for more than 4 years. Designated FM-U and FM-M, the two substrains share the same marker chromosome, t(5q-;6p+), but are karyotypically different, possessing hypodiploid chromosome numbers (39-43) in the former and hypertriploid (69-76) in the latter. Thus far, the two strains have passed through 117 and 156 subcultures or more than 230 and 310 cumulative population doublings, respectively, each passage requiring 4-6 days in the former and 3-4 days in the latter. In the process of immortalization, sequential rearrangement among various chromosomes presumably due to telomeric and interstitial telomeric fusions took place following the telomere shortening, particularly in the senescence and postsenescence phase cells. Of particular interest is the fact that loss of heterozygosity (LOH) of the p53 gene was demonstrated in these immortalized cell populations. In addition, the allelic patterns of the LOH of p53 differed. Further evidence indicative of infinite proliferation was demonstrated in both strains, such as the telomere elongation and the significantly low frequency of cells possessing dicentric chromosomes.


Assuntos
Transformação Celular Neoplásica , Aberrações Cromossômicas , Guerra Nuclear , Adulto , Idoso , Sequência de Bases , Células Cultivadas , Deleção Cromossômica , Impressões Digitais de DNA , Feminino , Fibroblastos , Genes p53 , Humanos , Dados de Sequência Molecular , Vírus 40 dos Símios/genética , Telômero
19.
Neuropediatrics ; 25(6): 325-30, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7770131

RESUMO

To investigate the pathogenesis of infantile spasms, 12 children underwent a combination of neurophysiologic and neuroimaging studies including brainstem evoked potentials and single photon emission computed tomography with 99mTcHMPAO. Three of the children had localized cerebral abnormalities on neuroimaging, i.e. right frontotemporal cortical microdysgenesis, left frontotemporal polymicrogyria, and right parietooccipitotemporal porencephalic cyst. Neurophysiologic studies also indicated that a single cerebral hemisphere was predominantly involved, while the other hemisphere and the brainstem were relatively spared, a result compatible with the clinical findings of hemiparesis and hemiconvulsion. In these three patients, administration of carbamazepine was followed by marked improvement of the clinical and electroencephalographic findings. Our results suggest that a combination of noninvasive examinations can distinguish a particular subtype of infantile spasms associated with a localized cerebral abnormality and responsive to carbamazepine.


Assuntos
Córtex Cerebral/anormalidades , Córtex Cerebral/fisiopatologia , Lateralidade Funcional , Espasmos Infantis/fisiopatologia , Carbamazepina/administração & dosagem , Carbamazepina/uso terapêutico , Córtex Cerebral/diagnóstico por imagem , Eletroencefalografia , Potenciais Evocados Auditivos do Tronco Encefálico , Potenciais Somatossensoriais Evocados , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Piridoxina/uso terapêutico , Espasmos Infantis/diagnóstico por imagem , Espasmos Infantis/tratamento farmacológico , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
20.
Res Commun Mol Pathol Pharmacol ; 86(3): 297-310, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7712106

RESUMO

The effects of acetaminophen (APAP) on stress-induced gastric mucosal lesions were investigated in rats treated with water-immersion restraint stress (WIR) for 3 hours. Three-hour WIR caused both significant increase in gastric lesions in terms of ulcer index and lipid peroxide levels and decrease in prostaglandin E2 (PGE2) levels in the stomach, compared with prestress control levels. When APAP (500mg/kg) was intraperitoneally (i.p.) administered into rats 2 hours before WIR, the stress-induced changes were significantly inhibited. Whereas, three-hour WIR markedly decreased total glutathione levels in the liver, but not in the stomach and plasma and simultaneously reduced glutathione (GSH) levels in the liver and stomach were markedly decreased. In addition to the enhancement of decrease in liver total glutathione levels, APAP pretreatment caused significant decrease in gastric and plasma total glutathione levels compared with prestress control levels. Moreover, co-administration of indomethacin (5mg/kg, i.p.) with APAP almost abolished the protective effects of APAP against the stress-induced ulceration. These results suggest that APAP may protect gastric mucosa from stress-induced ulceration, probably through the promoted production of PGE2 in the gastric mucosa without restoring glutathione levels.


Assuntos
Acetaminofen/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Úlcera Gástrica/prevenção & controle , Animais , Dinoprostona/metabolismo , Combinação de Medicamentos , Mucosa Gástrica/metabolismo , Glutationa/metabolismo , Indometacina/farmacologia , Injeções Intraperitoneais , Peróxidos Lipídicos/metabolismo , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar , Úlcera Gástrica/etiologia , Úlcera Gástrica/metabolismo , Estresse Fisiológico/complicações
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