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1.
J Chemother ; 20(3): 319-23, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18606586

RESUMO

The present study aimed to examine the peritoneal pharmacokinetics and pharmacodynamic exposure of intravenous cefotiam. One gram of cefotiam was administered to eight patients before abdominal surgery. Venous blood and peritoneal fluid (PF) samples were obtained at the end of infusion (0.5 h) and 1, 2, 3, 4, 5, and 6 h afterwards. The drug concentrations in the plasma and PF were determined, analyzed pharmacokinetically, and used for a stochastic simulation with minimum inhibitory concentration (MIC) data. Cefotiam penetrated well into the PF with the area under the drug concentration-time curve ratio of 0.88 +/- 0.18 (mean +/- SD, n = 8). Regarding the pharmacodynamic exposures against Escherichia coli and Klebsiella species, the probabilities of attaining the bacteriostatic target (40% of the time above MIC) in the PF using 0.5 g every 12 h, 1 g every 12 h, and 2 g every 12 h were 88.3-93.6%. However, 1 g every 8 h was needed for 89.7 and 91.6% probabilities of attaining the bactericidal target (70% of the time above MIC). These results should help us to understand better the peritoneal pharmacokinetics of cefotiam while also helping us to choose the appropriate dosage for intra-abdominal infections.


Assuntos
Antibacterianos/farmacocinética , Líquido Ascítico/metabolismo , Infecções Bacterianas/tratamento farmacológico , Cefotiam/farmacocinética , Infecção da Ferida Cirúrgica/tratamento farmacológico , Cavidade Abdominal/microbiologia , Cavidade Abdominal/cirurgia , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Cefotiam/administração & dosagem , Cefotiam/farmacologia , Escherichia coli/efeitos dos fármacos , Feminino , Humanos , Injeções Intravenosas , Klebsiella/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Método de Monte Carlo , Estudos Prospectivos
2.
Food Chem Toxicol ; 46(3): 1125-30, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18155340

RESUMO

Resveratrol, a polyphenolic phytoalexin, has free-radical scavenging activity and we found that it induces chromosomal aberrations, micronuclei, and sister chromatid exchanges in vitro. We synthesized its analogue 4-hydroxy-trans-stilbene (4-OH) and found that it has the same in vitro clastogenic activities as resveratrol, suggesting that the 4' hydroxy group of resveratrol is responsible for the effect. We fed resveratrol and 4-OH to young adult ICR mice at 0, 0.2, 2, or 20 ppm in their standard powder diet for 6 months and investigated the antioxidative effects. Half of each group was given 3000 ppm potassium bromate (KBrO(3)) in water for the last week to cause oxidative damage. Body weight gain tended to increase in males at 0.2 ppm resveratrol or 4-OH, and in females at 2 ppm 4-OH. Micronucleus (MN) analysis in bone marrow erythrocytes showed that the KBrO(3) tendency to induce MN was not prevented by the dietary resveratrol or 4-OH, which themselves did not induce MN under the present conditions. In this pilot study, resveratrol and 4-OH showed no obvious effect, either beneficial or adverse, at doses that are feasible in daily life for humans.


Assuntos
Antioxidantes/farmacologia , Dieta , Estilbenos/farmacologia , Animais , Antioxidantes/administração & dosagem , Peso Corporal/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Testes para Micronúcleos , Projetos Piloto , Resveratrol , Estilbenos/administração & dosagem
3.
J Clin Pharm Ther ; 33(6): 677-84, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19138246

RESUMO

OBJECTIVE: This study aimed to develop a population pharmacokinetic model for high-dose methotrexate (MTX), specifically focusing on the drug urinary excretion process. METHODS AND RESULTS: Three hundred and forty-eight serum samples and 416 urine samples from 51 Japanese adult patients with malignancies were concurrently fitted into a multi-compartment model using the nonmem program. In the final model, creatinine clearance (CCR, mL/min) and the MTX dose (DOSE10G; 0 when <10 g, 1 when >or=10 g) were the most significant factors that affected the renal clearance (CL(r)) and non-renal clearance (CL(nr)), respectively: CL(r)(L/h) = 5.57 x (CCR/80.0)(0.112), V(1)(L) = 26.9, Q(L/h) = 0.0778, V(2)(L) = 2.27, CL(nr)(L/h) = 0.567 x 3.39(DOSE10G), where V(1) and V(2) are the volumes of distribution of the central and peripheral compartments, respectively, and Q is the inter-compartmental (central-peripheral) clearance. For another nine patients, the model enabled a satisfactory Bayesian estimation using two time-point serum concentrations. CONCLUSION: The newly developed population pharmacokinetic model should improve the quality of serum concentration monitoring of high-dose MTX to predict and control toxic events.


Assuntos
Antimetabólitos Antineoplásicos/farmacocinética , Metotrexato/farmacocinética , Modelos Biológicos , Neoplasias/tratamento farmacológico , Adolescente , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Teorema de Bayes , Creatinina/sangue , Creatinina/urina , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos/métodos , Feminino , Previsões , Humanos , Japão , Masculino , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Dinâmica não Linear , Estudos Retrospectivos , Software , Distribuição Tecidual , Adulto Jovem
4.
Int J Gynecol Cancer ; 16(2): 772-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16681759

RESUMO

Cyclooxygenase-2 (COX-2) inhibition suppressed the growth of various tumors. The augmentation of antitumor immunity by increasing cytotoxic lymphocytes may be an important mechanism for COX-2 inhibition. Among cervical cancers, adenocarcinomas present more aggressive behavior and overexpressed COX-2. The expression of COX-2 and the CD8+ lymphocyte infiltrations were evaluated in this study by immunohistochemistry. We studied COX-2 expression and CD8+ lymphocyte infiltration in 55 women with cervical adenocarcinomas. COX-2 expression and tumor stromal CD8+ lymphocytes were evaluated by semiquantified methods. Tumor intraepithelial lymphocytes were counted under microscopic field of x200. Correlations between these data and other clinicopathologic features were investigated. Thirty-seven out of 55 (67.3%) cervical adenocarcinomas significantly expressed COX-2. Patients who died within 5 years showed higher percentage of COX-2 expression than survivors (100% vs 58.1%, P < 0.05). Victims also showed lesser intraepithelial CD8+ lymphocyte counts than survived patients (3.4 vs 26.4, P < 0.05). COX-2 expression and tumor intraepithelial lymphocyte count were reversely correlated with each other (correlation index: -0.38, P < 0.01). Up-regulated COX-2 expression and lesser tumor intraepithelial CD8+ lymphocyte count are poor prognostic indicators for cervical adenocarcinoma patients. COX-2 may play an important role in the suppression of host antitumor immunity in cervical adenocarcinomas.


Assuntos
Adenocarcinoma/enzimologia , Adenocarcinoma/imunologia , Linfócitos T CD8-Positivos/imunologia , Ciclo-Oxigenase 2/metabolismo , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/imunologia , Adenocarcinoma/patologia , Feminino , Humanos , Metástase Linfática/imunologia , Metástase Linfática/patologia , Linfócitos do Interstício Tumoral , Pessoa de Meia-Idade , Invasividade Neoplásica/imunologia , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Prognóstico , Regulação para Cima , Neoplasias do Colo do Útero/patologia
5.
Abdom Imaging ; 30(5): 637-40, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16132436

RESUMO

We report a case of mixed gonadal dysgenesis in which diffusion-weighted magnetic resonance imaging played a major role in the detection of ectopically located gonads. Magnetic resonance imaging may have a potential in detecting ectopically located gonads and may provide important information for the management of patients with mixed gonadal dysgenesis.


Assuntos
Imagem de Difusão por Ressonância Magnética , Disgenesia Gonadal Mista/diagnóstico , Adulto , Feminino , Humanos
6.
Kyobu Geka ; 57(11): 1011-5, 2004 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-15510813

RESUMO

We analyzed 7 patients with malignant pleural mesothelioma who underwent extrapleural pneumonectomy. Six men and a woman had a mean age of 65 years old. The postoperative mortality rate was 14% (1 death) and morbidity, 43% (3 cases). According to staging of International Mesothelioma Interest Group, 2 patients had stage I disease, 1 did stage II, 3 did stage III and 1 did stage IV. Local recurrences were found in 3 patients and metastasis in 2. In patients with local recurrences, 2 had irradiation with chemotherapy and 1, irradiation. In patients with recurrences of metastasis, 1 had chemotherapy and 1, supportive care. Seven patients with extrapleural pneumonectomy and 10 without surgery had median survivals of 16 months and 10 months, 1-year survival rates of 71% and 40% and 2-year survival rates of 57% and 0% respectively (p=0.071). Extrapleural pneumonectomy with adjuvant therapy could be effective treatment for malignant pleural mesothelioma.


Assuntos
Mesotelioma/cirurgia , Neoplasias Pleurais/cirurgia , Pneumonectomia/métodos , Idoso , Feminino , Humanos , Masculino , Mesotelioma/terapia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Pleurais/terapia
7.
Hepatogastroenterology ; 51(58): 1215-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15239282

RESUMO

BACKGROUND/AIMS: Gastroduodenostomy (Billroth I) or gastrojejunostomy (Billroth II) after distal gastrectomy is associated with duodenogastric reflux and remnant gastritis. This study sought to determine which reconstructive procedure is least likely to cause remnant gastritis and to determine the correlation between duodenogastric reflux and remnant gastritis. METHODOLOGY: Sixty patients who underwent curative distal gastrectomy for gastric cancer were classified into three groups by reconstructive procedure: group A, Roux-Y (n=18); group B, Billroth I (n=25); group C, Billroth II (n=17). Intragastric bile reflux was monitored using the Bilitec 2000 14 days after surgery, and endoscopy was performed and a patient questionnaire was completed 12 weeks after surgery. RESULTS: Bile reflux occurred in 23.9%, 40.4%, and 73.4% of the time (p<0.001), and remnant gastritis developed in 33%, 76%, and 100% of patients (p<0.001), in groups A, B, and C, respectively. Helicobacter pylori infection did not correlate with remnant gastritis (p=0.57). Symptoms following Roux-Y reconstruction were comparable to those following Billroth I and II reconstructions. CONCLUSIONS: Roux-Y reconstruction following distal gastrectomy is superior to Billroth I and II reconstruction in preventing remnant gastritis because it reduces duodenogastric reflux.


Assuntos
Anastomose em-Y de Roux , Gastrectomia , Coto Gástrico , Gastrite/prevenção & controle , Gastroenterostomia , Neoplasias Gástricas/cirurgia , Idoso , Refluxo Duodenogástrico/epidemiologia , Refluxo Duodenogástrico/prevenção & controle , Feminino , Gastrite/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reoperação , Neoplasias Gástricas/patologia , Inquéritos e Questionários
8.
Kyobu Geka ; 56(13): 1144-6, 2003 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-14672028

RESUMO

A 66-year-old man was admitted to our hospital for detailed investigation of an abnormal shadow on his chest X-ray. Chest radiography and computed tomography(CT) of the chest showed mediastinal lymphadenopathy and a tumor shadow in the left upper lobe. Biopsy of the mediastinal lymph nodes by mediastinoscopy showed that sarcoid nodules existed in all the biopsies nodes. Therefore, the lymphadenopathy was thought to be sarcoidosis or sarcoid reaction accompanied with lung cancer. Left upper lobectomy and dissection of hilar and mediastinal lymph nodes were performed. Although sarcoid nodules were seen in all the dissected lymph nodes, the cancer involved #5 and #14 lymph nodes. He died of brain metastasis 10 months after surgery.


Assuntos
Adenocarcinoma/secundário , Granuloma/patologia , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Idoso , Humanos , Metástase Linfática , Masculino , Mediastino , Sarcoidose/patologia
9.
Br J Cancer ; 89(12): 2293-8, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14676809

RESUMO

Ovarian cancer is believed to develop from the ovarian surface epithelium through the accumulation of aberrations of oncogenes and/or tumor suppressor genes. However, it is unclear how the gene abnormalities are involved in ovarian carcinogenesis. To elucidate the process, we transfected genes reported to show their abnormalities in human ovarian cancers into human ovarian surface epithelial cells. Immortalization of the cells was achieved by the transfection of SV40 large T antigen (LT) and human telomerase reverse transcriptase (hTERT); however, the resultant cells showed no tumorigenesis. Additional transfection of either c-erbB-2 or mutant Ha-ras into the immortalized cells showed the anchorage-independent growth and tumorigenesis in mice with the incidence of 50% and 40%, respectively. Histologically, all the tumours were undifferentiated. In association with the tumorigenesis, the cells expressing c-erbB-2 or mutant Ha-ras demonstrated increased vascular endothelial growth factor secretion under hypoxia and enhanced resistance to apoptosis compared with the immortalized cells. Collectively, the introduction of either c-erbB-2 or mutant Ha-ras in the cells, which were efficiently immortalized by the transfection of LT and hTERT, showed tumorigenicity, suggesting that c-erbB-2 or mutant Ha-ras genes might be involved in ovarian carcinogenesis.


Assuntos
Transformação Celular Neoplásica/genética , Células Epiteliais/fisiologia , Genes erbB-2/genética , Genes ras/genética , Neoplasias Ovarianas/genética , Feminino , Expressão Gênica/genética , Humanos , Ovário/citologia , Ovário/fisiopatologia , Transfecção/métodos , Células Tumorais Cultivadas
10.
Surg Endosc ; 17(3): 515-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12399847

RESUMO

BACKGROUND: The efficacy of thoracoscopic radical esophagectomy for cancer of the thoracic esophagus and the learning curve required have yet to be clearly established. METHODS: Eighty treatment-naive patients with esophageal cancer without contiguous spread underwent esophageal mobilization and extensive mediastinal lymphadenectomy through a 5-cm minithoracotomy and four trocar ports. The outcomes in the first 34 patients (group 1) and the last 46 patients (group 2) were compared. RESULTS: There were no differences in background or clinicopathologic factors between the two groups. The duration of the thoracoscopic procedure and blood loss were less (p <0.0001), the incidence of postoperative pulmonary infection was less (p = 0.0127), and the number of mediastinal nodes retrieved was greater (p = 0.0076) in group 2. Multivariate analysis demonstrated that surgical experience (number of cases performed) predicted the risk of pulmonary infection (p = 0.0331). CONCLUSION: Video-assisted thoracoscopic radical esophagectomy can be performed with safety and efficacy comparable to those of open esophagectomy. Morbidity decreases with the surgeon's experience.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia/normas , Aprendizagem , Excisão de Linfonodo/métodos , Cirurgia Torácica Vídeoassistida/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Perda Sanguínea Cirúrgica , Esofagectomia/efeitos adversos , Esofagectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cirurgia Torácica Vídeoassistida/efeitos adversos
11.
Kyobu Geka ; 55(13): 1115-9, 2002 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-12476560

RESUMO

Fourteen of 15 patients (93%) with retained pleural collections underwent successful enzymatic debridement and tube drainage with streptokinase-streptodornase (SK-SD) injections. No significant adverse reactions occurred. One patient required decortication when SK-SD therapy failed. Intrapleural SK-SD is a safe, effective means of removing retained proteinaceous collections in the pleural space. It may obviate the need for more invasive procedures.


Assuntos
Desbridamento , Desoxirribonuclease I/uso terapêutico , Drenagem/métodos , Empiema Pleural/cirurgia , Hemotórax/cirurgia , Estreptoquinase/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cavidade Pleural
12.
Surg Endosc ; 16(11): 1588-93, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12085146

RESUMO

BACKGROUND: The efficacy of thoracoscopic radical esophagectomy for cancer has yet to be established, mainly because previous reports have not included a sufficient number of cases. METHODS: Seventy-five treatment-naive patients with esophageal cancer without contiguous spread underwent esophageal mobilization and extensive mediastinal lymphadenectomy through a 5-cm mini-thoracotomy and four trocar ports. RESULTS: Video-assisted thoracoscopic surgery was performed without major intraoperative complications or emergency conversion to open surgery. We retrieved 34.1+/-13.0 mediastinal nodes, including 11.5+/-3.8 tracheobronchial nodes and 6.2+/-3.0 recurrent laryngeal nodes. Mean time of operation and blood loss were less in the last 39 patients than the first 36 (186.7+/-25.3 min and 165.4+/-101.8 g vs 270. 2+/-96.0 min and 421.5+/-31.2 g, respectively: p <0.0001 and p <0.001). Pulmonary morbidity was 5% in the later 39 patients. Survival was 90%, 80%, and 57% at 1, 2, and 5 years after surgery. CONCLUSION: Thoracoscopic radical esophagectomy has less morbidity and comparable survival to conventional surgery, after a moderate amount of experience. Mini-thoracotomy is essential to perform the procedure safely and effectively.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Excisão de Linfonodo/métodos , Cirurgia Torácica Vídeoassistida/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica , Feminino , Humanos , Complicações Intraoperatórias , Laringe/cirurgia , Pneumopatias/epidemiologia , Masculino , Mediastino/cirurgia , Pessoa de Meia-Idade , Morbidade , Complicações Pós-Operatórias/epidemiologia , Fatores de Tempo
13.
J Surg Res ; 101(2): 130-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11735267

RESUMO

BACKGROUND: Anterior mediastinal masses derive from a variety of diseases. Thymomas have been shown to commonly hold CD4(+)CD8(+) double-positive (DP) lymphocytes, and identification of this subset by two-color flow cytometric study was suggested to help diagnosis of thymoma. Several other thymic diseases, however, possibly hold CD4(+)CD8(+) DP lymphocytes. In this study, we utilized the three-color flow cytometric method for further examination of the phenotypes of lymphocytes in the thymic diseases. MATERIALS AND METHODS: One hundred eight specimens (77 primary and 10 metastatic thymomas, 10 thymic carcinomas, 2 thymic carcinoids, 4 malignant lymphomas, 2 seminomas, an inflammatory pseudotumor, and 2 nonneoplastic thymic hyperplasias) were subjected to the study. The expressions of CD3, CD4, and CD8 on tumor-associated lymphocytes were evaluated by three-color flow cytometric study. RESULTS: The proportion of the CD4(+)CD8(+) DP subset was more than 30% in all 78 lymphocyte-rich thymomas, in 2 malignant lymphomas, and in both thymic hyperplasias. CD3 expression of the CD4(+)CD8(+) DP subset ranged from a negative to a high level in thymomas and thymic hyperplasias, while it was restricted to a particular level in CD4(+)CD8(+) DP-type malignant lymphomas. The proportion of CD3(+) cells in the CD4(+)CD8(-) single-positive subset was consistently less than 90% in the lymphocyte-rich thymomas, while it was more than 90% in the thymic hyperplasias. CONCLUSION: Although identification of the CD4(+)CD8(+) DP subset in the tumor-associated lymphocytes does not necessarily indicate thymoma, a further characterization of thymic neoplasms possessing the CD4(+)CD8(+) DP subset was enabled by three-color flow cytometric study, suggesting the utility of this method as an ancillary tool for differential diagnosis of these diseases.


Assuntos
Citometria de Fluxo , Linfócitos T/imunologia , Timoma/imunologia , Neoplasias do Timo/imunologia , Complexo CD3/análise , Antígenos CD4/análise , Antígenos CD8/análise , Humanos , Hiperplasia , Timo/patologia
14.
J Am Chem Soc ; 123(36): 8662-6, 2001 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-11535070

RESUMO

Photolabile 6-nitrobenzo[a]pyrene (6-nitroBaP) released nitric oxide (NO) under visible-light irradiation. The generation of NO and the concomitant formation of the 6-oxyBaP radical were confirmed by ESR. BaP quinones were also detected as further oxidized products of the 6-oxyBaP radical. No such photodegradation was observed with other nitrated BaPs, such as 1-nitroBaP and 3-nitroBaP. DNA-strand breakage, caused by photoexcited 6-nitroBaP, was closely related to its NO-releasing activity. MO calculations of nitrated BaP suggest that the perpendicular conformation of the nitro substituent to the aromatic ring is important for the release of NO with light. These findings may be useful for the development of a new type of NO donor.


Assuntos
Benzopirenos/química , Benzopirenos/efeitos da radiação , DNA/química , DNA/efeitos da radiação , Luz , Óxido Nítrico/química , Fotoquímica
16.
Mutat Res ; 494(1-2): 107-13, 2001 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-11423350

RESUMO

We tested the genotoxicity of 3,5,4'-trihydroxystilbene (resveratrol), a polyphenolic phytoalexin found in grapes, in a bacterial reverse mutation assay, in vitro chromosome aberration (CA) test, in vitro micronucleus (MN) test, and sister chromatid exchange (SCE) test. Resveratrol was negative in the strains we used in the bacterial reverse mutation assay (S. typhimurium TA98 and TA100 and E. coli WP2uvrA) in the absence and presence of a microsomal metabolizing system. It induced structural CAs at 2.5-20 microg/ml and showed weak aneuploidy induction in a Chinese hamster lung (CHL) cell line. It induced MN cells and polynuclear and karyorrhectic cells after 48h treatments in the in vitro MN test. In the SCE test, resveratrol caused a clear cell-cycle delay; at 10 microg/ml, the cell cycle took twice as long as it did in the control. Resveratrol induced SCEs dose-dependently at up to 10 microg/ml, at which it increased SCE six-fold, and the number was almost as large as mitomycin C, a strong SCE inducer. No second mitoses were observed at 20 microg/ml even after 54h. Cell cycle analysis by FACScan indicated that resveratrol caused S phase arrest, and 48h treatment induced apoptosis. Our results suggest that resveratrol may preferentially induce SCE but not CA, that is, it may cause S phase arrest only when SCEs are induced.


Assuntos
Flavonoides , Mutagênicos/toxicidade , Fenóis/toxicidade , Polímeros/toxicidade , Troca de Cromátide Irmã , Estilbenos/toxicidade , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Aberrações Cromossômicas , Cricetinae , Relação Dose-Resposta a Droga , Pulmão/citologia , Testes de Mutagenicidade , Polifenóis , Resveratrol
17.
Mutagenesis ; 16(3): 183-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11320141

RESUMO

Nitro-azabenzo[a]pyrenes, 1- or 3-nitro-azabenzo[a]pyrene and their N-oxides are nitrated derivatives of azabenzo[a] pyrene (ABP) containing nitrogen in the 6-position of benzo[a]pyrene (B[a]P). The nitro-ABP-N-oxides (ABPOs) were formed by reaction of ABP with excess HNO(3). These derivatives were noteworthy as potent mutagens for Salmonella strains, and were present in fine particles of diesel particulates. In this study, micronucleus induction in mice and chromosomal aberrations due to means of Chinese hamster lung fibroblast (CHL) cells were investigated to determine genotoxicity in order to define the relationship with the mutagenic potency of these derivatives. The induction of micronucleus polychromatic erythrocytes (MNPCEs) was dependent on the dose response of 10-40 mg for 3-N-6-ABP, and of 10-40 mg for 1-N-6-ABP, and in addition, 1- and 3-N-6-ABPOs markedly induced MNPCEs in a dose range of 10-400 mg and from 1 to 80 mg, respectively, when the compound was intraperitoneally administrated in two mice at each dose. The results show that of the four compounds, 3-N-6-ABPO demonstrated a marked increase in MNPCES: On the other hand, chromosomal aberrations of the four compounds were investigated by the duplicate tests using CHLS: The results after a 48 h treatment induced aberrations of the chromatid type, chromatid breaks and exchanges for 1- and 3-N-6-ABP, and mainly chromatid exchanges for 1- and 3-N-6-ABPO. The frequency of chromosomal aberrations associated with nitro substitution on the ABPO structure. Chromosomal aberrations of nitro derivatives of ABPO substituted at the 3-position on the structure were more potent than those at the 1-postion. N-oxide derivatives have been found to be reduced to anion radicals much more easily than azaB[a]P and its nitro derivatives. This suggests that the electrochemical reduction of the chemicals plays an important role in the metabolic activation of nitrated B[a]P derivatives.


Assuntos
Benzo(a)pireno/toxicidade , Benzopirenos/toxicidade , Aberrações Cromossômicas , Animais , Benzo(a)pireno/análogos & derivados , Benzo(a)pireno/química , Benzopirenos/química , Cromátides/efeitos dos fármacos , Cumarínicos/toxicidade , Cricetinae , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Camundongos , Testes para Micronúcleos , Modelos Químicos , Mutagênese , Oxigênio/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Fatores de Tempo
18.
Biochem Biophys Res Commun ; 280(1): 48-52, 2001 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-11162476

RESUMO

Nitropyrenes are carcinogenic pollutants. Adduct formation following nitro-reduction is considered to be a major cause of nitropyrene-mediated DNA damage. We investigated the role of 1-nitrosopyrene, a metabolite of 1-nitropyrene, in causing oxidative DNA damage, using 32P-5'-end-labeled DNA. 1-Nitrosopyrene was found to facilitate Cu(II)-mediated DNA damage in the presence of NADH. Catalase and a Cu(I)-specific chelator attenuated DNA damage, indicating the involvement of H2O2 and Cu(I). Typical *OH scavenger did not have a significant effect. These results suggest that the main reactive species is probably a DNA-copper-hydroperoxo complex. We also measured 8-oxo-7,8-dihydro-2'-deoxyguanosine formation by 1-nitrosopyrene in the presence of Cu(II) and NADH, using an electrochemical detector coupled to a high-pressure liquid chromatograph. We conclude that oxidative DNA damage, in addition to DNA adduct formation, may play an important role in the carcinogenesis of nitropyrenes.


Assuntos
Carcinógenos/toxicidade , Dano ao DNA , Desoxiguanosina/análogos & derivados , Genes p53 , Genes ras , Pirenos/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Cromatografia Líquida de Alta Pressão , Cobre/farmacologia , DNA/química , DNA/efeitos dos fármacos , Desoxiguanosina/análise , Eletroquímica/métodos , Sequestradores de Radicais Livres/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Cinética , NAD/química , Fenantrolinas/química , Fenantrolinas/farmacologia , Pirenos/química
19.
Biochem Biophys Res Commun ; 280(4): 1183-8, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11162652

RESUMO

Galectin-3, a member of beta-galactoside-binding lectin family, is suggested to be an AGE-receptor. To examine this possibility, we prepared CHO cells overexpressing human galectin-3 (galectin-3-CHO cells). Galectin-3-CHO cells showed a specific and saturable binding to (125)I-AGE-BSA with Kd of 3.1 microg/ml. (125)I-AGE-BSA was endocytosed by galectin-3-CHO cells and underwent lysosomal degradation. The endocytosis of (125)I-AGE-BSA was inhibited not only by unlabeled AGE-BSA but also by acetylated LDL and oxidized LDL, ligands for the scavenger receptor family. Furthermore, (125)I-oxidized LDL and (125)I-acetylated LDL were actively endocytosed by galectin-3-CHO cells and the incubation with acetyl-LDL led to intracellular accumulation of cholesteryl esters, indicating the role of galectin-3 in endocytosis of AGE-proteins and modified LDLs. Since galectin-3 was localized and up-regulated in foam cells at human atherosclerotic lesions, the present results suggest that galectin-3 plays an important role in formation of atherosclerotic lesions in vivo, by modulating endocytic uptake of AGE-proteins and modified LDLs.


Assuntos
Antígenos de Diferenciação/fisiologia , Endocitose , Produtos Finais de Glicação Avançada/metabolismo , Lipoproteínas LDL/metabolismo , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/imunologia , Células CHO , Bovinos , Cricetinae , Relação Dose-Resposta a Droga , Galectina 3 , Humanos , Cinética , Ligantes , Oxigênio/metabolismo , Albumina Sérica/metabolismo , Transfecção
20.
Am J Surg Pathol ; 25(1): 103-10, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11145244

RESUMO

We examined the clinical and functional significance of histologic classification of thymic epithelial neoplasms proposed by the World Health Organization (WHO), based on an analysis of 146 consecutive tumors derived from 141 patients and 47 normal thymuses derived from children ranging in age from 1 to 9 years. Invasive tumors were seen in 12.5%, 38.6%, 40.0%, 69.4%, 80.0%, and 100% of type A, AB, B1, B2, B3, and C primary tumors, respectively. All of six recurrent or metastatic lesions were type B2 tumors. Myasthenia gravis was associated in 0%, 6.8%, 40.0%, 55.6%, 10.0%, and 0% in patients with type A, AB, B1, B2, B3, and C tumors, respectively. The average number (x10(6)) of tumor-associated CD4+CD8+ cells present in 1 g of tumor tissue was 1.5, 391.1, 1041.7, 333.9, 24.5, and 0.2 in type A, AB, B1, B2, B3, and C, respectively, and it was 1168.2 in the normal thymuses. Thus, type B1 tumor retained the function to induce CD4+CD8+ double-positive cells at a level comparable to that of the normal thymic cortical epithelial cells, followed by type AB and type B2 tumors. Type A and B3 tumors had this function at a barely detectable level, and type C tumor was nonfunctional. WHO histologic classification was shown to reflect the clinical features and the T-cell-inducing function of thymic epithelial tumors.


Assuntos
Relação CD4-CD8 , Timoma/classificação , Neoplasias do Timo/classificação , Organização Mundial da Saúde , Diferenciação Celular , Criança , Pré-Escolar , Humanos , Lactente , Miastenia Gravis/complicações , Estadiamento de Neoplasias , Linfócitos T/fisiologia , Timoma/imunologia , Timoma/patologia , Timo/patologia , Neoplasias do Timo/imunologia , Neoplasias do Timo/patologia
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