RESUMO
antisera against DNA modified with r-7,t-8-dihydroxy-9,10-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene (BPDE-1) was elicited in rabbits. Such sera reached with either single- or double-stranded modified DNA but not with unmodified DNA, free benzo(a)pyrene, or proteins modified by BPDE-1. Indirect immunofluorescence studies indicated that the immunoglobulin G in the sera bound specifically to the nuclei of KD cells which were treated with BPDE-1. The intensity of fluorescence was proportional to the dose of BPDE-1 used to treat the cells. About 50% of the BPDE-1-DNA adducts remained bound to DNA 24 hr after the removal of the carcinogen. The location of BPDE-1-modified bases in Col E1 DNA was visualized by immunoelectron microscopy.
Assuntos
Benzopirenos/metabolismo , DNA/metabolismo , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido , Especificidade de Anticorpos , Benzopirenos/imunologia , DNA/imunologia , Reparo do DNA , Imunofluorescência , Microscopia EletrônicaRESUMO
Micromolar concentrations of fecapentaene-12, a mutagen found in human feces, decrease survival measured as colony-forming efficiency and membrane integrity of cultured human fibroblasts. Fecapentaene-12 also decreases the content of cellular free low-molecular-weight thiols including glutathione. Fecapentaene-12 reacts directly with glutathione by causing both decreased levels of free thiol and some concomitant formation of oxidized glutathione, indicating that thiol depletion is a result of both alkylation and oxidative reactions. Exposure of cells to 2 or 5 microM fecapentaene-12 causes significant amounts of DNA-interstrand cross-links and DNA-single strand breaks, respectively, whereas exposure to a higher concentration of fecapentaene-12, i.e., 10 microM, also causes significant DNA-protein cross-links. Results from the reaction of fecapentaene-12 with isolated plasmid DNA parallel the cellular pattern of DNA damage; primarily interstrand cross-links and strand breaks occur also in plasmid DNA. Taken together, these studies show that fecapentaene-12 is a potent cytotoxic and genotoxic agent which can react with cellular thiols and cause several types of DNA damage.
Assuntos
Dano ao DNA , Glutationa/metabolismo , Mutagênicos/farmacologia , Polienos/farmacologia , Pele/efeitos dos fármacos , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , DNA Bacteriano/efeitos dos fármacos , DNA Bacteriano/ultraestrutura , Diamida/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Cinética , Microscopia Eletrônica , Plasmídeos/efeitos dos fármacos , Pele/citologia , Pele/metabolismo , Compostos de Sulfidrila/metabolismo , Trioxsaleno/farmacologiaRESUMO
A new compound with an immunosuppressive property was purified from culture filtrates of Isaria sinclairii and was chemically modified to FTY720. Rat spleen cells incubated with FTY720 demonstrated features characteristic of apoptosis--such as the absence of surface microvilli, chromatin condensation, and the formation of apoptotic bodies--by electron microscopy, and genemic DNA fragmentation by agarose gel electrophoresis. When FTY720 was administered in liver-allografted rats at a dose of 0.5 mg/kg from day 1 to day 14 after transplantation, the recipients survived significantly longer than the control group. Pretransplant treatment with 5 mg/kg of FTY720 one day before and on the day of grafting induced a remarkable prolongation of recipient survival, and three of 10 recipients survived for longer than 50 days. Furthermore, administration of FTY720 at 5 mg/kg on days 3 and day 4 after grafting also prolonged survival. In canine kidney allografting, a pretransplant 2-day course of FTY720 at 5 mg/kg prolonged graft survival. Daily administration of FTY720 in combination with CsA resulted in a significant prolongation of graft survival in a synergistic manner. In addition, FTY720 appeared to be nontoxic in canine recipients. These results demonstrated that FTY720, having a unique mechanism of action, induces long-term graft acceptance in rat and dog allotransplantation.
Assuntos
Rejeição de Enxerto/prevenção & controle , Imunossupressores/administração & dosagem , Transplante de Fígado , Propilenoglicóis/administração & dosagem , Animais , Morte Celular/efeitos dos fármacos , Células Cultivadas , Cães , Cloridrato de Fingolimode , Sobrevivência de Enxerto , Masculino , Propilenoglicóis/farmacocinética , Ratos , Esfingosina/análogos & derivados , Baço/efeitos dos fármacos , Baço/patologia , Transplante HomólogoRESUMO
Aiming the selection of possible candidates for the reactor cells in a hybrid artificial liver, we investigated the activities of 7-ethoxycoumarin deethylation and ammonia removal in 31 hepatocytes cell lines established from the human, rat, mouse, and chicken, compared with freshly isolated rat hepatocytes. Rat liver homogenate and hepatocytes showed 7-ethoxycoumarin deethylation activity of 0.925 and 1.840 nmol/mg protein/min, respectively. Two human hepatoblastoma cell lines, Hep G2 and HuH 6, showed the activity of 0.190 and 0.027 nmol/mg protein/min, respectively. While the rat hepatocytes efficiently removed added ammonia form the culture medium, no ammonia removal activity was detectable in any cell line with the assay conditions in this study. Ammonia removal activity, possibly catalyzed by the urea cycle, is likely to be harder to restore than the drug metabolizing system in the course of cell immortalization.
Assuntos
Amônia/metabolismo , Cumarínicos/metabolismo , Fígado Artificial , Fígado/citologia , Animais , Transplante de Células/métodos , Galinhas , Hepatoblastoma , Humanos , Camundongos , Ratos , Ratos Wistar , Espectrometria de Fluorescência , Células Tumorais Cultivadas/metabolismoRESUMO
Plasmid-mediated transformation and mutagenesis induced by (+/-)-trans-benzo[alpha]pyrene-7,8-dihydrodiol-9,10-oxide (BP-DEI) in recipient Escherichia coli (E. coli) have been studied. Because plasmid DNA is used, the system is entirely free from direct toxic effects of BP-DEI on the recipient cells. Plasmid pK0482 DNA, which has two dominant genes, beta-lactamase (amp-r) and galactokinase (galK) was modified with BP-DEI prior to its transformation of E. coli N99, AB1157, AB2463(recA-) and AB1886(uvrA-). Transformants were selected by ampicillin resistance and mutations were analyzed simultaneously by the altered expression of the galK gene. (1) Approx. 3 molecules of BP-DEI per molecule of pK0482 DNA decreased the transformation efficiency to 37% in AB1157 and the mutation frequency in this strain was proportional to the amount of BP-DEI covalently bound to pK0482 DNA. (2) In Ab1886(uvrA-) a 37% transformation efficiency was produced by only 1 molecule of BP-DEI per molecule of pK0482 DNA, and the mutation frequency in this strain was higher than in AB1157. (3) In AB2463(recA-), the transformation efficiency was similar to that obtained with AB1157, but mutagenesis was clearly suppressed. (4) Polyacrylamide gel patterns of restriction digests of the pK0482 mutated at the galK gene were indistinguishable from those of the unmutated plasmid DNA.
Assuntos
Benzopirenos , Mutação , Fatores R , Transformação Genética , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido , Fenômenos Químicos , Química , Reparo do DNA , Enzimas de Restrição do DNA/metabolismo , DNA Bacteriano/genética , DNA Circular , Escherichia coli/genética , Galactoquinase/genética , Conformação de Ácido NucleicoRESUMO
A 55-year-old male consulted a local doctor with the complaint of epigastralgia. Examination of the upper gastrointestinal tract revealed gastric cancer (Borrmann Type II) and he was referred to our hospital for operation. A few lymph nodes were palpable in the left supraclavicular fossa, and the biopsy of those lymph nodes revealed metastatic adenocarcinoma. The CT scan of the abdomen showed enlargement of paraaortic lymph nodes. Then, the patient was determined inoperable (T3, N4, H02 P01, M1 stage IVb). He was treated as an outpatient with UFT-E (300 mg/day, orally), Krestin (PSK 3.0 g/day, orally) and Mitomycin C (MMC 6 or 8 mg once a week, intravenously repeated interval of 4 weeks). The total dose of UFT-E, PSK and MMC was 219 g, 1,095 g and 136 mg, respectively. One month later, lymph nodes in the supraclavicular fossa disappeared, and the lesion in the stomach completely responded. We have followed the patient for more than one year. He visits our the outpatient department and has kept working until now.
Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/secundário , Esquema de Medicação , Combinação de Medicamentos , Humanos , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Proteoglicanas/administração & dosagem , Neoplasias Gástricas/patologia , Tegafur/administração & dosagem , Uracila/administração & dosagemRESUMO
Hemodynamics studies were carried out from days 1-5 following the onset of illness in 7 patients with severe pancreatitis (group A) and in 7 patients with moderate pancreatitis (group B). Patients in both groups had a higher cardiac index (CI) and a lower systemic vascular resistance (SVR) than normal patients during 5 days of illness, and patients in group A had a higher CI of 5.38 +/- 0.841 x min/m2 and lower SVR of 889 +/- 234dyn.sec/cm5 than those in group B on day 4. Patients in group A had a lower pulmonary vascular resistance than normal patients on days 1, 3, and 4, but those in group B did not show this hemodynamic change. Group A patients had a higher pulmonary wedge pressure of 11.9 +/- 8.4mmHg and depressed left ventricular stroke work index of 59.8 +/- 17.8g.m/m2 as compared with group B (5.6 +/- 3.4mmHg, 77.7 +/- 23.6g./m2, respectively). These findings indicate that a hyperdynamic hemodynamic state may exist in the early stages of moderate and severe pancreatitis and myocardial depression may be evident in severe pancreatitis.
Assuntos
Hemodinâmica , Pancreatite/fisiopatologia , Doença Aguda , Adulto , Idoso , Feminino , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/complicações , Circulação Pulmonar , Insuficiência Respiratória/etiologia , Resistência VascularRESUMO
Recent progress of molecular biology has elicited the pathogenesis of arterial and venous thrombosis at the cellular level. The pathogenesis, as well as the etiology of the sequelae, has become clear to be closely relevant to inflammatory cytokines and growth factors such as tumor recrosis factor (TNF) alpha, interleukin-1 beta, or vascular endothelial growth factor (VEGF). From this point of view, the anti-cytokine or the anti-growth factor therapy including the use of some proteins, antibodies, drugs, and gene delivery systems has every possibility of improving the therapeutic outcome for the thrombosis.