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1.
Eur J Epidemiol ; 20(12): 1023-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16331434

RESUMO

In Japan, the main source of dioxins is incinerators. This study examined the relationship between the distance of schools from municipal waste incineration plants and the prevalence of allergic disorders and general symptoms in Japanese children. Study subjects were 450,807 elementary school children aged 6-12 years who attended 996 public elementary schools in Osaka Prefecture in Japan. Parents of school children completed a questionnaire that included items about illnesses and symptoms in the study child. Distance of each of the public elementary schools from all of the 37 municipal waste incineration plants in Osaka Prefecture was measured using geographical information systems packages. Adjustment was made for grade, socioeconomic status and access to health care per municipality. Decreases in the distance of schools from the nearest municipal waste incineration plant were independently associated with an increased prevalence of wheeze, headache, stomach ache, and fatigue (adjusted odds ratios [95% confidence intervals] for shortest vs. longest distance categories =1.08 [1.01-1.15], 1.05 [1.00-1.11], 1.06 [1.01-1.11], and 1.12 [1.08-1.17], respectively). A positive association with fatigue was pronounced in schools within 4 km of the second nearest municipal waste incineration plant. There was no evident relationship between the distance of schools from such a plant and the prevalence of atopic dermatitis or allergic rhinitis. The findings suggest that proximity of schools to municipal waste incineration plants may be associated with an increased prevalence of wheeze, headache, stomach ache, and fatigue in Japanese children.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Proteção da Criança/estatística & dados numéricos , Exposição Ambiental/efeitos adversos , Eliminação de Resíduos , Instituições Acadêmicas , Fatores Etários , Criança , Humanos , Incineração , Japão/epidemiologia , Medição de Risco , Fatores Socioeconômicos
2.
Protein Eng ; 14(9): 663-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11707612

RESUMO

The thermostability enhancement of Flavobacterium meningosepticum glycerol kinase (FGK) by random mutagenesis in the subunit interface region was investigated. A single Escherichia coli transformant, which produced a more thermostable glycerol kinase than the parent enzyme, was obtained. The nucleotide sequence of the gene of the mutant enzyme (FGK2615) was determined, and the four amino acid replacements were identified as Glu327 to Asp, Ser329 to Asp, Thr330 to Ala and Ser334 to Lys. Although the properties of FGK2615 were fundamentally similar to those of the parent enzyme, the thermostability and Km for ATP had changed. The thermostability of FGK2615 was apparently increased; the temperature at which the enzyme activity is inactivated by 50% for a 30-min incubation of FGK2615 was determined to be 72.1 degrees C which was 3.1 degrees C higher than that of the parent FGK. Four additional mutants each having a single amino acid replacement (Glu327 to Asp, Ser329 to Asp, Thr330 to Ala and Ser334 to Lys) were prepared and their thermostability and Km for substrates were evaluated. The effect of the substitution of Ser329 to Asp is discussed.


Assuntos
Ácido Aspártico/genética , Flavobacterium/enzimologia , Glicerol Quinase/química , Glicerol Quinase/genética , Serina/genética , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Ácido Aspártico/química , Sequência de Bases , Sítios de Ligação , Estabilidade Enzimática/genética , Flavobacterium/genética , Regulação Bacteriana da Expressão Gênica , Glicerol Quinase/isolamento & purificação , Glicerol Quinase/metabolismo , Temperatura Alta , Modelos Moleculares , Mutagênese , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Serina/química , Especificidade por Substrato , Fatores de Tempo
3.
Proc Natl Acad Sci U S A ; 97(24): 13039-44, 2000 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-11078532

RESUMO

Two arginine residues, Arg-181 and Arg-268, are conserved throughout the known family of FMN-containing enzymes that catalyze the oxidation of alpha-hydroxyacids. In the lactate oxidase from Aerococcus viridans, these residues have been changed to lysine in two single mutations and in a double mutant form. In addition, Arg-181 has been replaced by methionine to determine the effect of removing the positive charge on the residue. The effects of these replacements on the kinetic and thermodynamic properties are reported. With all mutant forms, there are only small effects on the reactivity of the reduced flavin with oxygen. On the other hand, the efficiency of reduction of the oxidized flavin by l-lactate is greatly reduced, particularly with the R268K mutant forms. The results demonstrate the importance of the two arginine residues in the binding of substrate and its interaction with the flavin, and are consistent with a previous hypothesis that they also play a role of charge neutralization in the transition state of substrate dehydrogenation. The replacement of Arg-268 by lysine also results in a slow conversion of the 8-CH(3)- substituent of FMN to yield 8-formyl-FMN, still tightly bound to the enzyme, and with significantly different physical and chemical properties from those of the FMN-enzyme.


Assuntos
Arginina , Mononucleotídeo de Flavina/metabolismo , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo , Streptococcaceae/enzimologia , Sequência de Aminoácidos , Substituição de Aminoácidos , Sítios de Ligação , Sequência Conservada , Mononucleotídeo de Flavina/análogos & derivados , Flavoproteínas/química , Flavoproteínas/metabolismo , Cinética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Termodinâmica
4.
Int J Hematol ; 71(3): 266-72, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10846834

RESUMO

The early diagnostic efficacy of serial Candida antigen detection by the assay kit CAND-TEC (a latex particle agglutination test) was evaluated in 12 episodes in 10 patients with acute leukemia after post-remission chemotherapy. To determine the timing to initiate antifungal chemotherapy, we performed the CAND-TEC assay serially in each patient. When the patients revealed febrile neutropenia after antileukemic chemotherapy and the Candida antigen titer was increased compared to that measured before the antileukemic chemotherapy (even if the increased titer was at a lower level, e.g., from negative to 1:1 positive or from 1:1 to 1:2), azole antifungal agents (fluconazole or miconazole) were administered intravenously. In 9 (81.8%) of the 11 evaluable cases, the antifungal chemotherapy was effective and the titers decreased to less than or equal to the previous titers in all cases. In 2 cases, the antifungal chemotherapy was not effective, and the titers did not decrease. These results suggest that serial Candida antigen detection provides a useful method in the early diagnosis of invasive candidiasis in febrile neutropenia and in determining the timing of the initiation of early antifungal chemotherapy. This method might also be useful in preventing the excess use of antifungal agents; thus preventing the proliferation of azole-resistant Candida infection.


Assuntos
Antifúngicos/uso terapêutico , Candida/imunologia , Candidíase/diagnóstico , Leucemia/tratamento farmacológico , Leucemia/microbiologia , Doença Aguda , Adulto , Idoso , Antígenos de Fungos/sangue , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Candidíase/sangue , Candidíase/imunologia , Feminino , Febre , Humanos , Leucemia/complicações , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/microbiologia , Masculino , Pessoa de Meia-Idade , Neutropenia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/microbiologia , Kit de Reagentes para Diagnóstico
5.
Proc Natl Acad Sci U S A ; 97(6): 2480-5, 2000 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-10706608

RESUMO

The native flavin, FMN, has been removed from the l-lactate oxidase of Aerococcus viridans, and the apoprotein reconstituted with 12 FMN derivatives with various substituents at the flavin 6- and 8-positions. Impressive linear relationships are exhibited between the sum of the Hammett final sigma(para) and final sigma(ortho) parameters and the redox potentials of the free flavins, and between the redox potentials of the free and enzyme-bound flavins. Rapid reaction kinetics studies of the reconstituted enzymes with the substrates l-lactate and l-mandelate show an increase in the reduction rate constant with increasing redox potential, except that, with lactate, a limiting rate constant of approximately 700 s(-1) is obtained with flavins of high potential. Similar breakpoints are found in plots of the rate constants for flavin N5-sulfite adduct formation and for the reaction of the reduced enzymes with molecular oxygen. These results are interpreted in terms of a two-step equilibrium preceding the chemical reaction step, in which the second equilibrium step provides an upper limit to the rate with which the particular substrate or ligand is positioned with the flavin in the correct fashion for the observed chemical reaction to occur. The relationship of rate constants for flavin reduction and N5-sulfite adduct formation with flavin redox potential below the observed breakpoint indicate development of significant negative charge in the transition states of the reactions. In the case of reduction by substrate, the results are consistent either with a hydride transfer mechanism or with the so called "carbanion" mechanism, in which the substrate alpha-proton is abstracted by an enzyme base protected from exchange with solvent. These conclusions are supported by substrate alpha-deuterium isotope effects and by solvent viscosity effects on sulfite binding.


Assuntos
Oxigenases de Função Mista/química , Apoenzimas , Mononucleotídeo de Flavina/análogos & derivados , Cinética , Ácido Láctico/metabolismo , Ácidos Mandélicos/metabolismo , Oxigenases de Função Mista/metabolismo , Oxirredução , Ligação Proteica , Venenos de Serpentes , Espectrofotometria , Streptococcaceae/química , Relação Estrutura-Atividade
6.
Rinsho Ketsueki ; 41(11): 1214-9, 2000 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-11193442

RESUMO

A 62-year-old man was diagnosed as being in the chronic phase of chronic myelogenous leukemia (CML) in 1990, and subsequently treated with hydroxyurea (HU). The total HU dose administered reached 2,929 g (average, 1.44 g/day). In December 1995, the patient was admitted to our hospital for control of the CML. Following HU therapy, he often experienced high fever (38-39 degrees C) due to infection or blastosis, and at that time his skin showed marked pigmentation, dryness and scaling with itching and anhidrosis. A skin biopsy sample from the left scapula showed atrophic change of the skin and epidermal tissues with fibrotic changes and damage to the subcutaneous glands. This was strongly suspected to have been caused by the continuous HU administration, and the anhidrosis and dryness was considered to have contributed to the patient's high body temperature. Frequent cooling of the patient's body was effective.


Assuntos
Antineoplásicos/efeitos adversos , Hidroxiureia/efeitos adversos , Hipo-Hidrose/etiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Pele/patologia , Humanos , Hipo-Hidrose/patologia , Masculino , Pessoa de Meia-Idade , Pele/efeitos dos fármacos , Tempo
7.
Rinsho Byori ; Suppl 109: 179-89, 1999 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-10198593
8.
Leuk Res ; 23(1): 37-42, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9933133

RESUMO

We examined the effect of PSC 833, a non-immunosuppressive cyclosporin analogue, on the cytotoxicity, accumulation and retention of idarubicin (IDA) and its 13-dihydro metabolite, idarubicinol (IDAol). P-glycoprotein (PGP)-overexpressing multidrug-resistant K562/D1-9 cells were used for these studies. PSC 833 had no effect on the cytotoxicity, intracellular accumulation, or retention of IDA and IDAol in the parent K562 cells. However, intracellular accumulation of IDA and IDAol in K562/D1-9 cells after a 60-min incubation was restored by 0.4 microM PSC 833 to 104% and 116%, respectively, of the level in parent K562 cells. The retention of IDA and IDAol in K562/D1-9 cells was also restored by 0.4 microM PSC 833. Consequently, 0.4 microM PSC 833 increased the sensitivity of K562/D1-9 cells to IDA and IDAol. The resistance index (RI) of IDA decreased from 20-fold to 4.0-fold, and the RI of IDAol decreased from 104-fold to 1.5-fold. These results suggest that the combination of IDA and PSC 833 may be effective in reversing PGP-mediated multidrug resistance in leukemia cells.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ciclosporinas/farmacologia , Daunorrubicina/análogos & derivados , Idarubicina/farmacologia , Células K562/efeitos dos fármacos , Daunorrubicina/farmacologia , Resistência a Múltiplos Medicamentos , Humanos
9.
Transfus Sci ; 20(1): 21-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10621555

RESUMO

AIM: To assess clinical usefulness of an intermittent-flow blood cell separator in peripheral blood stem cell (PBSC) collection and transplantation. RESULTS: The Haemonetics Multi Component System (Multi) was used to collect PBSC (52 aphereses in 17 patients). The mean processing blood volume and the mean PBSC yield were 7407 ml and 2.16 x 10(6) CD34+ cells/kg, respectively. When CD34+ cells exceeded 0.3% of the peripheral WBC, more than 2.0 x 10(6) CD34+ cells/kg could be collected by a single apheresis. Eight patients underwent PBSC transplantation after high-dose chemotherapy. Hematopoietic recovery was achieved in a median period of 10 days. CONCLUSIONS: (1) A single-arm, light-weight machine has sufficient capability to collect PBSC. (2) The percentage of CD34+ cells in the peripheral WBC is a good predictor of the CD34+ cell yield of the collection.


Assuntos
Coleta de Amostras Sanguíneas , Separação Celular/instrumentação , Transplante de Células-Tronco Hematopoéticas , Neoplasias/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Cytotechnology ; 31(3): 255-63, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19003149

RESUMO

The expression of glycosylphosphatidylinositol (GPI-anchored) carcinoembryonic antigen (CEA) and alkaline phosphatase (ALP) on the cell surface of various cancer cell lines and a lung diploid cell line (WI38) was investigated, with exposure of the cell lines to a cell differentiation agent (sodium butyrate) to induce cell differentiation and expression of the two tumor-associated antigens. In three colon (SW1222, SW1116, and HT-29) and stomach (MKN-45) cancer cell lines, all of which are double producers of CEA and ALP, the maximum expression of GPI-anchored CEA occurred with butyrate at a lower concentration than did that of GPI-anchored ALP. GPI-anchored ALP derived from colon (SW1222 and SW1116) and stomach (MKN-45 and MKN-1) cancer cell lines was heat-stable with and without exposure to butyrate, but GPI-anchored ALP derived from lung cancer cell lines (PC-6, PC13, PC-14, WI26VA4, and WI38VA13) showed a variety of heat stabilities, depending on cell line, butyrate exposure, and SV40 transformation.

11.
Biochim Biophys Acta ; 1388(2): 444-56, 1998 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-9858779

RESUMO

A gene encoding a thermostable ascorbate oxidase (ASOM) was cloned from Acremonium sp. HI-25 and sequenced. The gene comprised 1709 bp and was interrupted by a single intron of 57 bp. ASOM consisted of 551 amino acids including a signal peptide with a molecular mass of 61200, and contained four histidine-rich regions with high sequence homology to the corresponding regions of other multicopper oxidases. The ASOM gene was expressed in Aspergillus nidulans under the Aspergillus oryzae Taka-amylase A gene promoter. The recombinant enzyme (An-ASOM) exhibited almost the same enzymatic properties as ASOM. The ASOM gene was mutated by site-directed mutagenesis with reference to the amino acid sequences of plant enzymes to generate enzymes with altered azide sensitivity. Site-directed mutagenesis at the trinuclear active copper site resulted in an increase in azide resistance; the Ala465Leu and Phe463Trp/Ala465Leu mutants exhibited approximately 10 and 20% increases in azide resistance, respectively.


Assuntos
Acremonium/enzimologia , Ascorbato Oxidase/genética , Azidas/farmacologia , Estabilidade Enzimática/genética , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação/genética , Clonagem Molecular , Sequência Conservada/genética , Cobre/metabolismo , Proteínas Fúngicas/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida/genética , Proteínas Recombinantes/genética , Mapeamento por Restrição , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Temperatura
12.
J Immunol Methods ; 217(1-2): 79-85, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9776577

RESUMO

An ELISA technique was developed to assay the distribution of native human monoclonal antibodies (mAbs) in tumor-xenografted SCID mice. This was used in an investigation of its potential as an alternative to the conventional radioisotopic technique for mAb biodistribution assays which would be simpler to implement and might yield results in closer accord with actual mAb activity because it is based on the use and detection of the native mAbs rather than their radioisotope-coupled immunoconjugates. SCID mice bearing xenografted tumors of the human lung adenocarcinoma cell line A549 received injections via the tail vein of four human mAbs that had been obtained from human-mouse heterohybridomas and were known to be reactive with A549. The biodistribution of the mAbs was assayed by the ELISA technique seven days after the mAb injection. The assay yielded tumor/serum ratios for the four reactive mAbs which were in the range of three to six and tumor mAb levels which were in the range of 0.28 to 0.92 %ID/g (percent of injected mAb dose per gram of tumor). The tumor mAb levels were thus lower than the levels commonly found by radioisotopic assay, and further investigation is desirable to determine the cause of the difference. The results indicate that ELISA can provide a simple, practical means of investigating the biodistribution of human mAbs in mice bearing xenografted carcinomas. The application of this procedure would obviate the need for the complex facilities and procedures associated with radioisotopic labelling and assay.


Assuntos
Anticorpos Monoclonais/farmacocinética , Anticorpos Antineoplásicos/análise , Ensaio de Imunoadsorção Enzimática , Imunoglobulina M/análise , Adenocarcinoma/imunologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Antineoplásicos/administração & dosagem , Feminino , Humanos , Imunoglobulina M/administração & dosagem , Injeções Intravenosas , Injeções Subcutâneas , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , Transplante de Neoplasias , Distribuição Tecidual , Transplante Heterólogo
13.
Kansenshogaku Zasshi ; 72(7): 694-700, 1998 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-9745218

RESUMO

Antibodies inhibiting human immunodeficiency virus type 1 (HIV-1) reverse transcriptase activity (RTI-antibody), Binding inhibition antibody (BI-antibody) and polymerization inhibition antibody (PI-antibody) were investigated for their ability to inhibiting RT activity in 248 HIV-1 infected individuals and 99 healthy individuals. In BI-antibody, high titer samples were determined more in than in RTI- and PI-antibodies. No significance was indicated between AC, ARC and AIDS is any antibody, however, progression from AC to AIDS was poled to high titer and low titer in RTI- and BI-antibodies. Moreover, time course of each antibody levels in the same infected individuals were resulted in no change, going up or down through all the experimental term, though all samples were collected in AC. These results were suggested that the determination factor of each stage in HIV progression would be multiple, and that the various dynamics of RTI-, BI- and PI-antibodies in the same infected individuals might be caused in the term from HIV infection to AIDS progression, prognosis or appearing of the drug resistant strain but stages of the disease.


Assuntos
Anticorpos/sangue , Infecções por HIV/imunologia , Transcriptase Reversa do HIV/imunologia , HIV-1 , Inibidores da Transcriptase Reversa/sangue , Síndrome da Imunodeficiência Adquirida/imunologia , Humanos
14.
Biochimie ; 80(4): 309-12, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9672750

RESUMO

Crystals of flavoenzyme L-lactate oxidase from Aerococcus viridans (LOX) have been obtained that diffract to 3.0 A resolution (P2(1)2(1)2(1), a = 118.4 A, b = 138.4 A, c = 194.6 A). Crystallographic studies suggest that the enzyme may exist as an octameric form with non-crystallographic two- and four-fold axes in the center of the octamer. The four-fold axis makes the tetramer tight, and the tetramers lie upon one another by the two-fold axis.


Assuntos
Oxigenases de Função Mista/química , Streptococcaceae/enzimologia , Cromatografia em Gel , Cristalização , Cristalografia por Raios X , Substâncias Macromoleculares , Oxigenases de Função Mista/isolamento & purificação , Ultrafiltração
15.
Biosci Biotechnol Biochem ; 62(12): 2388-95, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9972265

RESUMO

A thermostable glycerol kinase (FGK) was purified 34-fold to homogeneity from Flavobacterium meningosepticum. The molecular masses of the enzyme were 200 kDa by gel filtration and 50 kDa by SDS-PAGE. The Km for glycerol and ATP were 0.088 and 0.030 mM, respectively. The enzyme was stable at 65 degrees C for 10 min and at 37 degrees C for two weeks. The enzyme gene was cloned into Escherichia coli and its complete DNA was sequenced. The FGK gene consists of an open reading frame of 1494-bp encoding a protein of 498 amino acids. The deduced amino acid sequence of the gene had 40-60% similarity to those of glycerol kinases from other origins and the amino acid sequence of the putative active site residue reported for E. coli GK is identical to the corresponding sequence of FGK except for one amino acid residue.


Assuntos
Flavobacterium/enzimologia , Glicerol Quinase/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Cromatografia em Agarose , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Escherichia coli/enzimologia , Escherichia coli/genética , Flavobacterium/genética , Regulação Bacteriana da Expressão Gênica , Glicerol Quinase/química , Glicerol Quinase/genética , Glicerofosfatos/análise , Temperatura Alta , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Cinética , Dados de Sequência Molecular , Peso Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Espectrofotometria , Especificidade por Substrato
16.
Hinyokika Kiyo ; 43(4): 291-4, 1997 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-9161859

RESUMO

We report a case of Bellini duct carcinoma of the left kidney with invasive growth pattern. A 39-year-old man was admitted to our hospital with the chief complaint of gross hematuria. Ultrasonography showed left renal swelling but normal reniform configuration of the kidney was maintained. Computed tomography demonstrated a low density tumor infiltrating into the renal cortex and with tumor extension into the renal vein. Renal angiography revealed a hypovascular tumor. We suspected a left renal cell carcinoma with tumor extension into the left renal vein, and performed radical nephrectomy. Macroscopically, the resected kidney had a normal outer contour. The tumor with infiltrative growth pattern existed in renal medulla. Histopathologic examination revealed a papillary adenocarcinoma originated in Bellini duct (pT3bN2M0). The patient underwent systemic chemotherapy (M-VAC). This case showed invasive growth pattern, which were different from the usual renal cell carcinoma and Bellini duct carcinoma.


Assuntos
Adenocarcinoma Papilar/patologia , Neoplasias Renais/patologia , Túbulos Renais Coletores/patologia , Adenocarcinoma Papilar/irrigação sanguínea , Adenocarcinoma Papilar/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Doxorrubicina/administração & dosagem , Humanos , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/tratamento farmacológico , Masculino , Metotrexato/administração & dosagem , Invasividade Neoplásica , Vimblastina/administração & dosagem
17.
J Immunol Methods ; 199(2): 175-84, 1996 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8982360

RESUMO

Using a solid-phase non-radioisotopic (non-RI) reverse transcriptase (RT) assay, antibodies inhibiting human immunodeficiency virus type 1 (HIV-1) RT activity (RTI antibody) were investigated for their ability to inhibit binding of RT to a template-primer and DNA polymerization. The RTI antibody inhibited the binding of RT to the template-primer (BI antibody), and directly reacted with the RT-template-primer complex and inhibited enzymatic activity (PI antibody). The RTI antibody interfered with formation of the RT-template-primer complex suggesting that it recognized the antigenic site involved in template-primer binding of RT molecules. Since deoxynucleotide triphosphates (dNTPs) blocked inhibition of the RT activity by the PI antibody, the antigenic site recognized by the PI antibody may be closely related to the dNTP binding site. The seropositivities of the BI and PI antibodies were 84.6% and 91.2%, respectively, in HIV-1-infected individuals; healthy individuals, HTLV-I-positive individuals, autoimmune disease patients and leukemia patients were all seronegative. No significant correlation of residual RT activities was observed when BI and PI antibodies were compared (r = 0.688). It is possible that the epitopes recognized by the BI antibody differs from those recognized by the PI antibody. The assays described are able to detect BI and PI antibodies in the sera of HIV-1-infected individuals.


Assuntos
Transcriptase Reversa do HIV/imunologia , Animais , Especificidade de Anticorpos , Ligação Competitiva , DNA Viral/biossíntese , Transcriptase Reversa do HIV/antagonistas & inibidores , Humanos , Imunoglobulina G , Ligação Proteica , DNA Polimerase Dirigida por RNA/imunologia , Coelhos , Proteínas Recombinantes , Moldes Genéticos
18.
J Biol Chem ; 271(45): 28300-5, 1996 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-8910450

RESUMO

A mutant form of L-lactate oxidase (LOX) from Aerococcus viridans in which alanine 95 was replaced by glycine was constructed as a mimic of L-lactate monooxygenase but proved instead to be a mimic of the long chain alpha-hydroxyacid oxidase from rat kidney. A95G-LOX keeps oxidase activity with L-lactate at the same level as wild type LOX but has much enhanced oxidase activity with longer chain L-alpha-hydroxyacids, alpha-hydroxy-n-butyric acid, alpha-hydroxy-n-valeric acid, etc., and also the aromatic alpha-hydroxyacid, L-mandelic acid. Kinetic analysis of the activity with these substrates indicates that the reduction of the enzyme bound flavin by substrates is the rate-limiting step in A95G-LOX. The affinity of pyruvate for the reduced enzyme is increased, and sulfite binding to the oxidized enzyme is weaker in A95G-LOX than in native enzyme. Wild type LOX stabilizes both the neutral and anionic flavin semiquinones with a pKa of 6.1, but A95G LOX stabilizes only the anionic semiquinone form. These results strongly suggest that the environment around the N5-C4a region of the flavin isoalloxazine ring is changed by this mutation.


Assuntos
Oxirredutases do Álcool/metabolismo , Oxigenases de Função Mista/metabolismo , Alanina , Oxirredutases do Álcool/genética , Animais , Estabilidade Enzimática , Glicina , Cinética , Oxigenases de Função Mista/genética , Mutagênese Sítio-Dirigida , Ácido Pirúvico/metabolismo , Ratos , Especificidade por Substrato
19.
Br J Cancer ; 74(3): 359-67, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8695349

RESUMO

Four monoclonal antibodies (MAbs) from hybridoma obtained by in vitro stimulation of regional lymph node lymphocytes from lung cancer patients and electrofusion of the stimulated cells with murine or human-mouse myeloma cells were reactive to lung cancer cells in enzyme-linked immunoabsorbent assay, and to lung cancer tissue in immunohistochemical analysis using acetone-methyl benzoate-xylene (AMeX) fixed tissue and in immunofluorescence analysis. Three of the MAbs (designated ZLG40, 27D57 and 28K29) recognised cell-surface antigens of the lung adenocarcinoma cell line A549 and the remaining one (designated 29D38) recognised nuclear membrane antigens of the same cell line. The three surface-binding MAbs showed a significant complement-dependent cytotoxicity (CDC) to the A549 cells, but the membrane-binding 29D38 showed no CDC to the A549 cells. Western blotting of the extracts of the A549 or PC6 (small-cell lung cancer) cell lines by the four MAbs showed a 28K29 antigen band at M(r) of approximately 600,000 (+/- 2-ME), a ZLG40 antigen band at M(r) 50,000 (+/- 2-ME), and one 29D38 antigen band at M(r) of more than 1,000,000 (-2-ME) and M(r) between 20,000 and 80,000 (+2-ME), but no detectable band for 27D57 antigen.


Assuntos
Adenocarcinoma/imunologia , Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/análise , Neoplasias Pulmonares/imunologia , Animais , Antígenos de Superfície/análise , Citotoxicidade Imunológica , Humanos , Immunoblotting , Imuno-Histoquímica , Camundongos , Peso Molecular , Células Tumorais Cultivadas
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