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1.
Phys Chem Chem Phys ; 18(44): 30740-30747, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27792236

RESUMO

The frequency of the resonance of 125Te of two organo-ditellurides, R-Te-Te-R (R = 4-CH3C6H4 and 2-(CH3)2NCH2C6H4), in solution undergoes a low-field shift as the concentration of the sample increases. In sharp contrast, the resonance of a sterically hindered ditelluride (R = (C6H5(CH3)2Si)3C) and telluric acid display the opposite effect. While the negative concentration coefficients can be explained by the change in magnetic susceptibility, the positive coefficients are consistent with autoassociation of the molecules through tellurium-centred supramolecular interactions. Although the corresponding equilibrium constants are small, the process is shown to be exothermic. However, the influence of autoassociation is much smaller than the effects of solvent polarity and the conformation of the ditelluride bond.

2.
Bone Marrow Transplant ; 35(7): 653-61, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15711571

RESUMO

SUMMARY: To reduce relapse following allogeneic transplantation for AML, intensification of high-dose busulfan/cyclophosphamide using additional agents has been investigated but with few reported comparisons. We compared an intensified regimen of etoposide (60 mg/kg), busulphan (14 mg/kg), and cyclophosphamide (120 mg/kg) (BuCyVP) with BuCy2 in 237 AML patients. No significant difference in overall outcome was observed following BuCyVP (n=127) or BuCy2 (n=110). The 5-year survival was 27.3 and 30.1% following BuCyVP and BuCy2, respectively (P=0.48). Similarly, the 5-year cumulative incidence of relapse (CIR) was 28.3 and 34.8% with BuCyVP and BuCy2 (P=0.45), respectively. On multivariable analysis, patients transplanted in CR1 (P=0.002) and from related donors (P=0.013) had longer survival, while disease status at transplant was the only factor predicting CIR (P=0.002). In a separate analysis of CR1 patients (n=56), there was no significant difference in survival (P=0.37) or CIR (P=0.87) between the two regimens. However, for more advanced disease, there was a trend towards less relapse with BuCyVP (P=0.08), which was balanced by a higher cumulative incidence of transplant-related deaths (P=0.03) compared to BuCy2, resulting in similar survival. Overall, our results do not support the use of the more intensive BuCyVP regimen over BuCy2 in either early or more advanced disease AML patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia Mieloide/terapia , Doença Aguda , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Bussulfano/administração & dosagem , Causas de Morte , Ciclofosfamida/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Doença Enxerto-Hospedeiro , Humanos , Leucemia Mieloide/complicações , Leucemia Mieloide/mortalidade , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento
3.
Bone Marrow Transplant ; 31(2): 87-93, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12621488

RESUMO

Age >or=50 years has been reported to be an adverse risk factor for allogeneic BMT, and consequently many of these patients are either not transplanted or treated on nonmyeloablative protocols. To study if older patients perform poorly relative to younger adults following myeloablative allogeneic transplants, we compared the outcomes of consecutive adults aged >or=50 years (n=51) to those <50 years (n=262) who received BU, CY+/-etoposide and allogeneic transplantation for AML, CML, MDS and NHL from 1984 to 2000. Median ages were 53 (range 50-66) and 35 (range 18-49) years for older and younger patients, respectively. Patients were low-risk if they had AML in CR1, CML in first chronic phase, refractory anemia, or NHL in remission or sensitive relapse at the time of transplantation. All others were high-risk. In patients with low-risk disease, there was no significant difference in overall survival (OS) between older and younger adults (P=0.64), while older patients tended to have a shorter OS among high-risk patients (P=0.06). The 3-year OS was 53% (95% CI, 29-77%) compared to 60% (95% CI, 50-69%) for older and younger patients with low-risk disease, respectively. The corresponding 3-year OS were 27% (95% CI, 11-43%) and 37% (95% CI, 25-45%) for high-risk patients. In low-risk patients, the incidence of acute and chronic graft-versus-host disease, and treatment-related mortality were similar in older and younger patients, while older patients experienced more treatment-related deaths by day 100. On multivariable analysis, age >or=50 years was a significant adverse factor only when high-risk patients were considered. We conclude that when radiation-free conditioning is used, age >or=50 years is not a significant adverse risk factor for allogeneic BMT in patients with low-risk disease, and that such patients should not be excluded from conventional myeloablative approaches until the efficacy of nonmyeloablative transplantation is better established.


Assuntos
Imunossupressores/uso terapêutico , Transplante de Células-Tronco , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/fisiologia , Adolescente , Adulto , Fatores Etários , Feminino , Seguimentos , Humanos , Leucemia/terapia , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/terapia , Transplante de Células-Tronco/mortalidade , Análise de Sobrevida , Fatores de Tempo , Transplante Homólogo/mortalidade , Resultado do Tratamento , Irradiação Corporal Total
4.
Bone Marrow Transplant ; 29(9): 763-7, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12040474

RESUMO

Therapeutic options for patients with Hodgkin's disease who relapse after high-dose chemotherapy with autologous stem cell support are limited. Salvage chemotherapy is not curative, and allogeneic stem cell transplantation in this setting is associated with mortality rates of 40-65%. We report our institution's experience with second autologous transplants in this patient population. Five patients (median age 36) with relapsed Hodgkin's disease underwent a second autologous stem cell transplant at a median of 66 months after first transplant. Four patients received CBV, and one patient received BuCy as conditioning. Neutrophil and platelet engraftment occurred by days +10 and +16, respectively. All patients achieved a complete response, and no relapses have occurred after a median follow-up of 42 months. All four patients who received CBV developed interstitial pneumonitis, and two patients died of pulmonary complications 37 and 48 months following second transplant. Three patients remain alive and disease-free 41, 42 and 155 months after second transplant. These data indicate that second autologous transplantation should be considered for selected patients who relapse after a prolonged response to first autologous transplant. However, BCNU pneumonitis is the major toxicity in patients who have undergone previous mantle radiation and received busulfan with first transplant.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Doença de Hodgkin/terapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Causas de Morte , Feminino , Seguimentos , Sobrevivência de Enxerto , Transplante de Células-Tronco Hematopoéticas/mortalidade , Doença de Hodgkin/mortalidade , Humanos , Cinética , Masculino , Recidiva , Indução de Remissão , Terapia de Salvação , Transplante Autólogo/métodos
5.
Bone Marrow Transplant ; 27(11): 1121-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11551021

RESUMO

Long-term outcome was analyzed in 28 patients transplanted between 1989 and 1992 following busulfan and cyclophosphamide and who had busulfan levels studied. While there was no significant correlation of busulfan levels with diagnosis, patients who had received extensive prior chemotherapy had a significantly higher area under the curve (AUC; P = 0.02) and maximum busulfan levels (Cmax; P = 0.03). High AUC was associated with the development of hepatic veno-occlusive disease (P = 0.03) and with early transplant-related mortality (P = 0.06). No significant correlation of busulfan levels with relapse, late non-relapse death, late complications, nor event-free survival was detected.


Assuntos
Antineoplásicos Alquilantes/toxicidade , Bussulfano/toxicidade , Hepatopatia Veno-Oclusiva/induzido quimicamente , Adolescente , Adulto , Antineoplásicos Alquilantes/sangue , Antineoplásicos Alquilantes/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Área Sob a Curva , Transplante de Medula Óssea/efeitos adversos , Transplante de Medula Óssea/mortalidade , Bussulfano/sangue , Bussulfano/farmacocinética , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Humanos , Estudos Longitudinais , Condicionamento Pré-Transplante/efeitos adversos , Resultado do Tratamento
6.
Bone Marrow Transplant ; 26(10): 1037-43, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11108300

RESUMO

Results in 164 patients who underwent allogeneic marrow transplantation following busulfan and cyclophosphamide over a 15 year period were analyzed. Age (median 37, range 14-66 years) did not significantly affect the incidence of graft-versus-host disease (GVHD), but patients who received methotrexate with cyclosporine had a significantly lower incidence (P = 0.002) of chronic GVHD compared to those who received methylprednisolone with cyclosporine. Hepatic veno-occlusive disease (VOD) occurred less frequently in chronic phase patients (P = 0.002) and in those transplanted shortly after diagnosis (P = 0.001). Five year leukemia-free survival (LFS) for the entire group was 49% (95% CI 41-57%). For 102 patients who underwent transplantation in chronic phase, results were significantly improved by transplantation at a short interval following diagnosis, particularly within 3 months (P = 0.01), by the use of methotrexate and not corticosteroids for GVHD prevention (P = 0.03), and by use of HLA-identical sibling donors (P = 0.01). Age was not a significant adverse prognostic factor and transplantation was successfully performed in individuals up to age 66. Allogeneic transplantation in CML, including older patients and those with unrelated donors, can be most safely and effectively performed shortly after diagnosis.


Assuntos
Transplante de Medula Óssea , Bussulfano/administração & dosagem , Ciclofosfamida/administração & dosagem , Doença Enxerto-Hospedeiro/prevenção & controle , Leucemia Mieloide Aguda/terapia , Adolescente , Adulto , Fatores Etários , Idoso , Transplante de Medula Óssea/efeitos adversos , Causas de Morte , Feminino , Proteínas de Fusão bcr-abl/análise , Hepatopatia Veno-Oclusiva/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Transplante Homólogo
7.
Bone Marrow Transplant ; 25(12): 1219-22, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10871724

RESUMO

Prognostic factors in 42 patients aged 11 to 62 (median 46) years, with myelodysplastic syndrome (MDS) or after leukemic transformation, who underwent allogeneic marrow transplantation between 1984 and 1999 were analyzed. Thirty-six had advanced disease morphology; 19 had leukemic transformation. Twenty-nine received a preparative regimen of BuCy2 and 13 busulfan 14 mg/kg, etoposide 50 mg/kg and cyclophosphamide 120 mg/kg. Severe hepatic veno-occlusive disease (VOD) occurred in three patients all of whom received anti-leukemic chemotherapy prior to transplantation. Fifteen patients (36%) died from early transplant-related complications; nine patients relapsed. The estimated 4 year disease-free survival (DFS) was 35% (95% CI 26-44%). Older age was the most significant adverse prognostic factor. Patients with leukemic transformation who underwent early transplantation had significantly better DFS than those treated first with chemotherapy (P = 0.002). Delayed toxicity was rare in these patients; no late relapses occurred. Bone Marrow Transplantation (2000) 25, 1219-1222.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Transplante de Medula Óssea , Bussulfano/administração & dosagem , Ciclofosfamida/administração & dosagem , Imunossupressores/administração & dosagem , Leucemia/terapia , Síndromes Mielodisplásicas/terapia , Adulto , Criança , Terapia Combinada , Humanos , Leucemia/fisiopatologia , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/fisiopatologia , Prognóstico , Transplante Homólogo
8.
Bone Marrow Transplant ; 25(12): 1243-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10871728

RESUMO

The purpose of the study was to determine the toxicities and effectiveness of a novel preparative regimen of busulfan (Bu) 14 mg/kg, etoposide 50 or 60 mg/kg, and cyclophosphamide (Cy) 120 mg/kg in non-Hodgkin's lymphoma (NHL) and to analyze results using doses based on different body weight parameters and the two different etoposide doses. Three hundred and eighty-two patients aged 16 to 72 underwent first autologous transplantation with mobilized peripheral blood progenitor cells between August 1992 and December 1998 at either of two transplant centers. Mucositis was the most common toxicity. Hepatic toxicity was the most common life-threatening toxicity; severe hepatic VOD occurred in 11 patients (2.9%). Ten patients (2.6%) died from treatment-related toxicity. The 3-year progression-free survival (PFS) for the entire group was 46.9% (95% CI, 40.5-53.3%). Elevated LDH, resistance to chemotherapy, and intermediate/aggressive histology were significant adverse prognostic factors. For patients in sensitive first relapse PFS was 47.0% (95% CI, 37-57%). Neither etoposide dose nor body weight parameter utilized significantly affected outcome. In conclusion, the novel preparative regimen of Bu, etoposide and Cy results in a low incidence of treatment-related mortality and is effective in the treatment of patients with NHL. Bone Marrow Transplantation (2000) 25, 1243-1248.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Linfoma não Hodgkin/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bussulfano/administração & dosagem , Bussulfano/efeitos adversos , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Humanos , Linfoma não Hodgkin/patologia , Análise de Sobrevida , Transplante Autólogo
9.
Mol Cell Biochem ; 195(1-2): 245-56, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10395089

RESUMO

Human macrophage inflammatory protein-1alpha (hMIP-1alpha) and human macrophage inflammatory protein-1beta (hMIP-1beta) are chemokines involved in a diverse range of immunological effects. Both hMIP-1alpha and hMIP-1beta are involved in the activation of monocytes and THP-1 cells probably through a common receptor(s). However, only hMIP-1alpha can bind to neutrophils with high affinity, presumably through CC-CKR1 (CKR1). Since the structure of these two proteins is highly conserved, non-conserved amino acids must define the disparate binding patterns that these two proteins exhibit. Measurements of binding, chemotaxis and calcium influx conducted with hMIP-1alpha and hMIP-1beta chimeric proteins and mutants show that two amino acids (37K and 43L) are important in the binding and signaling of hMIP-1alpha through CKR1. Furthermore, we also show that mutations of the three charged amino acids at the C-terminus of hMIP-1alpha and hMIP-1beta (amino acids 61, 65 and 67), do not adversely affect the binding to THP-1 cells.


Assuntos
Aminoácidos/metabolismo , Proteínas Inflamatórias de Macrófagos/metabolismo , Neutrófilos/metabolismo , Receptores de Quimiocinas/metabolismo , Sequência de Aminoácidos , Cálcio/metabolismo , Células Cultivadas , Quimiocina CCL4 , Humanos , Células K562 , Leucina/metabolismo , Lisina/metabolismo , Proteínas Inflamatórias de Macrófagos/isolamento & purificação , Proteínas Inflamatórias de Macrófagos/farmacologia , Dados de Sequência Molecular , Ligação Proteica , Receptores de Quimiocinas/isolamento & purificação , Proteínas Recombinantes de Fusão/síntese química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Células U937
10.
J Clin Oncol ; 15(2): 759-65, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9053502

RESUMO

PURPOSE: We analyzed the safety and effectiveness of high-dose etoposide (2 g/m2) followed by granulocyte colony-stimulating factor (G-CSF) as a peripheral-blood progenitor cell (PBPC) mobilization regimen and assessed extent of tumor reduction in patients with breast cancer, non-Hodgkin's lymphoma (NHL), and Hodgkin's disease (HD). PATIENTS AND METHODS: One hundred sixty-nine consecutive patients who eventually underwent PBPC transplantation received treatment with high-dose etoposide (2 g/m2) followed by daily G-CSF (5 microg/kg). RESULTS: This mobilization method was effective in nearly all patients. No patients died of mobilization-related complications. A 50% reduction in tumor size was seen in 19% of assessable patients with breast cancer, 44% of those with NHL, and 38% of those with HD. Hematopoietic recovery (HR) following transplantation occurred in all patients. Patients with > or = 4 x 10(6) CD34+ cells/kg engrafted with neutrophils at a median of 9 days after transplant and patients with at least 1.2 x 10(6) CD34+/CD33- cells/kg achieved platelet recovery at a median of 15 days. CONCLUSION: Etoposide plus G-CSF is an effective and safe method for mobilization of PBPCs. Etoposide is an effective agent in tumor reduction in NHL and HD and is less effective in breast cancer. The substantially lower incidence of prior exposure to this agent compared with cyclophosphamide favors its use.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Etoposídeo/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Células-Tronco Hematopoéticas/efeitos dos fármacos , Doença de Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Adolescente , Adulto , Idoso , Antineoplásicos Fitogênicos/administração & dosagem , Coleta de Amostras Sanguíneas , Neoplasias da Mama/terapia , Criopreservação , Etoposídeo/administração & dosagem , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin/terapia , Humanos , Imunofenotipagem , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade
11.
Bone Marrow Transplant ; 18(5): 907-11, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8932844

RESUMO

Between March 1984 and March 1995, 76 patients with advanced acute myelogenous, acute lymphoblastic, or chronic myelogenous leukemia underwent allogeneic marrow transplantation from HLA-identical or one-antigen mismatched sibling or unrelated donors. Patients received a preparative regimen consisting of busulfan 16 mg/kg and cyclophosphamide 120 mg/kg or busulfan 14 mg/kg, cyclophosphamide 120 mg/kg and etoposide (VP-16) 50 mg/kg. For GVHD prevention, patients received cyclosporine with either methotrexate or steroids or FK506 with methotrexate. Fourteen patients were leukemia-free survivors at a median of 6.5 years (range 1-11 years) following transplantation. For the group as a whole, the estimated leukemia-free survival (LFS) at 5 years is 20% (95% confidence interval 10-30%). Ten of the 14 leukemia-free survivors developed acute GVHD greater than grade II and chronic GVHD and two developed only chronic GVHD. Significantly better relapse rates and disease-free survival were associated with the development of acute and/or chronic GVHD. In the absence of acute GVHD and/or chronic GVHD, patients who underwent transplantation for advanced leukemia, after preparation with Bu/CY or Bu/CY/VP-16, were very likely to experience disease recurrence. Novel strategies designed to promote development of GVHD present a promising area for investigation to improve outcome in patients with leukemia at high risk for relapse.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Transplante de Medula Óssea , Doença Enxerto-Hospedeiro , Leucemia/terapia , Transplante de Medula Óssea/efeitos adversos , Bussulfano/administração & dosagem , Terapia Combinada , Ciclofosfamida/administração & dosagem , Etoposídeo/administração & dosagem , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/fisiopatologia , Humanos , Leucemia/mortalidade , Leucemia/fisiopatologia , Resultado do Tratamento
12.
Phys Med Biol ; 40(4): 683-9, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7610122

RESUMO

Three dosimetric methods for commissioning the dynamic wedges on a Varian 600C linear accelerator operating at 4.7 MV were compared. The techniques involved the use of ionization chambers, x-ray verification film and solid state detectors. Ionization chambers gave the most accurate results, as expected, but data acquisition was very time consuming. Film dosimetry was found to have good spatial resolution for beam profiles, but problems were encountered with the acquisition of depth doses. Solid state detectors generally showed reasonable agreement with the ionization chambers.


Assuntos
Modelos Estruturais , Aceleradores de Partículas , Dosagem Radioterapêutica , Radioterapia/métodos , Dosimetria Fotográfica , Humanos
13.
Blood ; 84(6): 1790-801, 1994 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-7521690

RESUMO

Macrophage inflammatory protein-1 alpha (MIP-1 alpha) and its human homologue GOS19.1/LD78 are members of the C-C chemokine/intercrine family of secreted proteins. They have proinflammatory properties and also inhibit cell cycle progression of hematopoietic stem cells. Characterization of MIP-1 alpha receptor(s) has been confused because of its reported aggregation to inactive forms. Using a defined monomeric form of MIP-1 alpha that is biologically active for stem cell inhibition and induction of oxidative metabolism in polymorphonuclear cells, we report the detection of high- and low-affinity receptor classes on human leukemic CD34+ blast cells, promyelocytic cells, monocytes, peripheral blood neutrophils, and T cells. Both high- and low-affinity classes are expressed simultaneously in promyelocytes and neutrophils. The calculated kd for high-affinity receptors correlates with the concentrations of MIP-1 alpha required to induce a biologic effect on stem cells and neutrophils. Cross-linking studies show that MIP-1 alpha associates with two cell surface proteins with apparent molecular masses of 92 kD and 52 kD. Direct competition binding studies combined with studies on the inhibition of stem cells show that human and murine MIP-1 alpha have different receptor-binding and biologic properties.


Assuntos
Citocinas/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Monocinas/metabolismo , Receptores de Quimiocinas , Receptores Imunológicos/metabolismo , Antígenos CD/análise , Antígenos CD34 , Ligação Competitiva , Quimiocina CCL4 , Reagentes de Ligações Cruzadas , Granulócitos/metabolismo , Humanos , Cinética , Leucemia , Proteínas Inflamatórias de Macrófagos , Peso Molecular , Monócitos/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/metabolismo , Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Células Tumorais Cultivadas
14.
J Nat Prod ; 57(1): 32-41, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7512623

RESUMO

Bioassay-directed fractionation of an EtOH extract of the moss Polytrichum pallidisetum (Polytrichaceae) led to the isolation of three novel benzonaphthoxanthenones, 1-O-methylohioensin B [6], 1-O-methyldihydroohioensin B [7] and 1,14-di-O-methyldihydroohioensin B [8], and two novel cinnamoyl bibenzyls, pallidisetin A [9] and pallidisetin B [10]. Their structures and relative stereochemistry were established by spectral analyses and chemical correlation. Compounds 6-10 exhibited cytotoxic activity against the human tumor cell lines RPMI-7951 melanoma and U-251 glioblastoma multiforme. These two types of compounds could hypothetically be derived from cinnamic acid and bibenzyls through different biogenetic pathways.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Benzofuranos/isolamento & purificação , Cinamatos/isolamento & purificação , Plantas Medicinais/química , Compostos Policíclicos/isolamento & purificação , Xantenos/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/farmacologia , Benzofuranos/farmacologia , Cinamatos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Leucemia P388/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Camundongos , Conformação Molecular , Peso Molecular , Compostos Policíclicos/farmacologia , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Células Tumorais Cultivadas , Xantenos/farmacologia
15.
J Neurooncol ; 6(2): 179-84, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2852219

RESUMO

Sialyltransferase-1 activity was studied in cultured 12-18 human glioma cells. The apparent Km and Vmax with variable LacCer concentrations were 32 microM and 197 pmoles/mg protein/hr and with variable CMP-NeuAc concentrations were 172 microM and 877 pmoles/mg protein/hr., respectively. The pH optimum towards exogenous LacCer was 6.0 and towards endogenous acceptors was 6.2. The optimum protein:detergent ratio was 1:1. Human beta interferon (1000 units/ml medium) increased sialyltransferase-1 activity only slightly on a protein basis but increased it 47% on a per cell basis. These results demonstrate that one of the biochemical effects of beta-interferon on 12-18 human glioma cells is to stimulate ganglioside synthesis.


Assuntos
Glioblastoma/enzimologia , Interferon Tipo I/farmacologia , Proteínas Recombinantes/farmacologia , Sialiltransferases/metabolismo , Linhagem Celular , Humanos , Cinética
16.
J Neuropathol Exp Neurol ; 44(4): 371-83, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2409238

RESUMO

Natural killer cells (NK) demonstrate cytotoxicity against a wide range of cultured cells without prior sensitization, and the sensitivity of many target cells to NK attack is altered by exposure to interferon. The structures on the target cells conferring sensitivity or resistance to NK are not known, but glycolipids are suggested to be related to NK susceptibility. To determine possible relationships between target cell glycolipids and NK cytolysis, the effects of human beta-interferon (IFN) on the neutral glycolipid composition and sensitivity to NK cytolysis of cultured cells from four human gliomas and two fetal brains were analyzed. Compared to MOLT-4 and Raji cells all six neural cell lines were quite resistant to NK, and IFN slightly increased this resistance. IFN also caused increases in the amounts of non-hydroxy fatty acid cerebroside, ceramide trihexoside, asialo-GM1, asialo-GM2 and globoside. Increased molar proportions of ceramide tri- and tetra-saccharides occurred in the two glioma lines which had the greatest increases in NK resistance following IFN exposure. It is concluded that neutral glycolipids may play a role in the mechanisms responsible for resistance of some glioma cells to NK cytolysis.


Assuntos
Astrocitoma/imunologia , Encéfalo/imunologia , Citotoxicidade Imunológica , Feto/fisiologia , Glioblastoma/imunologia , Glicolipídeos/metabolismo , Células Matadoras Naturais/imunologia , Astrocitoma/metabolismo , Astrocitoma/patologia , Encéfalo/citologia , Encéfalo/embriologia , Encéfalo/metabolismo , Células Cultivadas , Feto/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Interferons/farmacologia , Neurônios/imunologia , Proteínas/metabolismo
17.
Cancer Res ; 45(3): 1033-9, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2578869

RESUMO

Human beta-interferon (IFN) induced an antiviral state in two fetal brain and six glioma cell lines. The growth-inhibitory effect of IFN was most pronounced on three glioblastoma lines and least on fetal brain and oligodendroglioma cells; IFN growth inhibition of one schwannoma and one anaplastic cell line was intermediate between the two other groups. Thus, the growth-inhibitory effect of IFN generally correlated with the degree of anaplasia of the tissue from which the cells were derived. IFN (1000 units/ml) had to be present for 24 to 48 hr to have a significant inhibitory effect on growth of glioblastoma (12-18) cells. However, growth inhibition of 12-18 cells exposed to IFN for 3 days persisted for 3 weeks. Both sialic acid-N-acetylgalactosamine ganglioside and a mixture of normal human brain gangliosides (50 microM) inhibited growth of fetal brain (CHII) but not glioblastoma 12-18 cells. However, preincubation of cells with either sialic acid-N-acetylgalactosamine or a mixture of gangliosides did not augment the growth-inhibitory effects of IFN on either CHII or 12-18. These results indicate that gangliosides and IFN may be operating through different mechanisms to cause growth inhibition.


Assuntos
Encéfalo/citologia , Gangliosídeos/farmacologia , Glioma/patologia , Interferons/farmacologia , Encéfalo/efeitos dos fármacos , Contagem de Células , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Feto , Glioma/tratamento farmacológico , Humanos , Gravidez
18.
Cell Immunol ; 90(2): 485-92, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2981642

RESUMO

Ten human neural tumor lines and three established from normal human brain were analyzed for sensitivities to natural killer (NK) cytolysis. Compared to MOLT-4, fetal brain cells were sensitive, but those from adult brain and eight of ten neural tumor cell lines demonstrated marked NK resistance. The frequencies of target-binding cells (TBC) and single-cell lysis of glioma cells bound within tumor cell conjugates demonstrated that the resistance of two lines was explained either by a decrease in the frequencies of TBC or reduced ability of bound NK cells to lyse the tumor cell conjugates. A third resistant line demonstrated decreases in both TBC and tumor cell conjugate lysis. Two glioma lines with less NK resistance had greater frequencies of TBC or conjugate lysis than the resistant lines. Thus, NK resistance can result from decreased recognition of targets, diminished NK lysis of bound targets, or a combination of both.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Encéfalo/fisiologia , Células Matadoras Naturais/imunologia , Astrocitoma/fisiopatologia , Células Cultivadas , Testes Imunológicos de Citotoxicidade , Feto , Glioblastoma/fisiopatologia , Glioma/fisiopatologia , Humanos , Neurilemoma/fisiopatologia , Oligodendroglioma/fisiopatologia , Ácidos Siálicos/fisiologia
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