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1.
Chem Commun (Camb) ; 53(1): 259-262, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27928568

RESUMO

A novel method combining elemental sulfur and selenium was developed, yielding crystalline sulfur-selenium compounds. The compounds were melted, and an organic comonomer added. Once the organic comonomer was consumed, the viscous compound was vitrified and allowed to cool yielding organic-inorganic hybrid polymers that are termed Organically Modified Chalcogenide (ORMOCHALC) polymers.

2.
Cancer Res ; 60(23): 6573-6, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11118035

RESUMO

p16 regulates the cell cycle pathway by inhibiting the cyclin Ds-cyclin-dependent kinase (CDK) 4/6-mediated phosphorylation of retinoblastoma protein (pRb). Previously, we reported that most primary T-cell acute lymphoblastic leukemia (T-ALL) harbored p16 inactivation and hyperphosphorylated pRb without cyclin Ds or CDK4/6 alterations. Therefore, inhibiting CDK4/6 may be an ideal therapeutic approach for p16 (-) T-ALL. UCN-01 (7-hydroxystaurosporine) is a potent antitumor agent that exerts its effects through the inhibition of CDKs. We now report that p16 protein expression status of T-ALL cells influences their sensitivity to UCN-01. In 36 primary T-ALL cells, the IC50s of UCN-01 in the 27 p16 (-) cells (43+/-52 nM) was significantly lower than that in the 9 p16 (+) cells (258+/-260 nM). Our results suggest that agents like UCN-01 may be useful as a p16-selective therapy for T-ALL.


Assuntos
Alcaloides/toxicidade , Antineoplásicos/toxicidade , Proteínas de Ciclo Celular , Inibidor p16 de Quinase Dependente de Ciclina/fisiologia , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Proteínas Supressoras de Tumor , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Inibidor de Quinase Dependente de Ciclina p15 , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , Inibidor p16 de Quinase Dependente de Ciclina/genética , Deleção de Genes , Regulação Leucêmica da Expressão Gênica , Inativação Gênica , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/metabolismo , Fosforilação , Proteína do Retinoblastoma/biossíntese , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estaurosporina/análogos & derivados , Células Tumorais Cultivadas
3.
Cancer Res ; 59(7): 1492-7, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10197619

RESUMO

Methylthioadenosine phosphorylase (MTAP) is an important enzyme for the salvage of adenine and methionine and is deficient in a variety of cancers including T-cell acute lymphocytic leukemia (T-ALL). Previously, we reported that the MTAP gene was deleted in over 30% of T-ALL patients at both diagnosis and relapse. We now report that MTAP-primary T-ALL cells are more sensitive to the toxicity of L-alanosine, an inhibitor of de novo AMP synthesis, than are MTAP+ primary T-ALL cells. As measured by [3H]thymidine incorporation, DNA synthesis in all seven MTAP-primary T-ALL cells was inhibited by L-alanosine with a mean IC50 of 4.8+/-5.3 ILM (range, 0.3-11.3 microM). On the other hand, the IC50 for 60% (12 of 20) of MTAP+ primary T-ALL was 19+/-18 microM (range, 1.7-67 microM; P = 0.02), whereas the remaining 40% (8 of 20) had an IC50 of >80 microM4. Furthermore, normal lymphocytes and MTAP+ primary T-ALL cells were rescued from L-alanosine toxicity by the MTAP substrate 5'-deoxyadenosine, but MTAP-T-ALL cells were not. These results indicate that normal cells, which are intrinsically MTAP+, would be protected from L.-alanosine toxicity, whereas MTAP-tumor cells would be killed. Thus, our results support the use of L-alanosine alone or in combination with a salvage agent as a MTAP-selective therapy and therefore lay the foundation for the initiation of clinical trials for the treatment of T-ALL and other MTAP-deficient malignancies with L-alanosine.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Purina-Núcleosídeo Fosforilase/metabolismo , Monofosfato de Adenosina/biossíntese , Alanina/análogos & derivados , Alanina/uso terapêutico , Humanos , Leucemia-Linfoma de Células T do Adulto/metabolismo , Reação em Cadeia da Polimerase , Purina-Núcleosídeo Fosforilase/deficiência , Purina-Núcleosídeo Fosforilase/genética , Timidina/metabolismo
5.
Appl Opt ; 38(15): 3206-13, 1999 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18319910

RESUMO

The change in the absorption loss of IR-transmitting chalcogenide glass fibers in the temperature range of -90 degrees C or= 6 microm the change in loss was mainly due to multiphonon absorption. The change in loss for tellurium-based glass fibers increased significantly at T = 60 degrees C. The increase in the loss at short wavelengths (lambda or= 9 microm, multiphonon absorption dominated the loss spectrum.

6.
J Clin Oncol ; 16(6): 2169-80, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9626218

RESUMO

PURPOSE: To evaluate the toxicity, immunogenicity, and pharmacokinetics of a human-mouse chimeric monoclonal antibody (mAb) ch 14.18 directed against disialoganglioside (GD2) and to obtain preliminary information on its clinical efficacy, we conducted a phase I trial in 10 patients with refractory neuroblastoma and one patient with osteosarcoma. PATIENTS AND METHODS: Eleven patients were entered onto this phase I trial. They received 20 courses of mAb ch 14.18 at dose levels of 10, 20, 50, 100, and 200 mg/m2. Dose escalation was performed in cohorts of three patients; intrapatient dose escalation was also permitted. RESULTS: The most prevalent toxicities were pain, tachycardia, hypertension, fever, and urticaria. Most of these toxicities were dose-dependent and rarely noted at dosages of 20 mg/m2 and less. Although the maximum-tolerated dose was not reached in this study, clinical responses were observed. These included one partial (PR) and four mixed responses (MRs) and one stable disease (SD) among 10 assessable patients. Biologic activity of ch 14.18 in vivo was shown by binding of ch 14.18 to tumor cells and complement-dependent cytotoxicity of posttreatment sera against tumor target cells. An anti-ch 14.18 immune response was detectable in seven of 10 patients studied. CONCLUSION: In summary, with the dose schedule used, ch 14.18 appears to be clinically safe and effective, and repeated mAb administration was not associated with increased toxicities. Further clinical trials of mAb ch 14.18 in patients with neuroblastoma are warranted.


Assuntos
Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/uso terapêutico , Gangliosídeos/imunologia , Neuroblastoma/terapia , Osteossarcoma/terapia , Adulto , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Criança , Pré-Escolar , Complemento C3/análise , Complemento C4/análise , Ensaio de Atividade Hemolítica de Complemento , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Infusões Intravenosas , Masculino , Camundongos , Neuroblastoma/metabolismo , Dor/induzido quimicamente , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/efeitos adversos , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/uso terapêutico , Resultado do Tratamento
7.
J Pediatr Hematol Oncol ; 17(3): 265-9, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7620926

RESUMO

PURPOSE: The combination of ifosfamide (I) and etoposide (E) was useful in salvaging patients with recurrent/resistant malignant solid tumors of childhood. Carboplatin (C), active against a number of pediatric cancers, was added to I and E to form a three-drug combination called ICE to improve the response rate. PATIENTS AND METHODS: ICE, consisting of I 1.5 g/m2 plus E 100 mg/m2 i.v.q.d. x 3 plus C i.v. on day 3 only, was given in 21-28-day intervals. C was started at 300 mg/m2, and the dose was escalated in 25% increments, with three evaluable patients treated at each level. RESULTS: Ninety-two patients were enrolled in this phase I/II study between July 1990 and April 1993. A total of 331 courses of ICE was administered. Median courses of ICE received were three (range, 1-16). The maximum tolerated dose (MTD) for C when used in combination was found to be 635 mg/m2. The response rate for ICE at the MTD for C was complete response (CR) 26% and CR + partial response (PR) 53%. The response was even better in those who received C at the MTD: 32% achieving a CR and 63% a CR + PR. Pancytopenia was the dose-limiting toxicity. Thirteen episodes of bacterial infection were reported, none fatal. Only one patient developed a Fanconi-like syndrome. CONCLUSION: The MTD of C when used with I and E was found to be 635 mg/m2. The overall CR + PR rate for all patients treated at all C dose levels was 53%. Best responses were seen in non-Hodgkin's lymphoma, neuroblastoma, soft tissue sarcomas, and Wilms' tumor.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Adolescente , Adulto , Carboplatina/administração & dosagem , Criança , Pré-Escolar , Etoposídeo/administração & dosagem , Feminino , Humanos , Ifosfamida/administração & dosagem , Lactente , Masculino , Recidiva
9.
Appl Opt ; 33(27): 6315-22, 1994 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-20941163

RESUMO

We have used telluride glass fibers fabricated in house to measure the evanescent-absorption spectra of water, methanol, ethanol, isopropanol, acetone, ethanoic acid, hexane, and chloroform. Furthermore, detection limits of less than 2 vol. % solute were obtained for mixtures of water and methanol, ethanol, isopropanol, acetone, and ethanoic acid. Techniques to reduce the detection limits are discussed.

10.
J Clin Oncol ; 11(11): 2218-25, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8229137

RESUMO

PURPOSE: To determine whether the information gained from staging laparotomy can be predicted by imaging and/or clinical factors in children with Hodgkin's disease. PATIENTS AND METHODS: Between 1986 and 1991, 216 consecutive pediatric patients with Hodgkin's disease underwent laparotomy and were treated on two concurrent protocols in a multiinstitutional cooperative group. All patients had computed tomography (CT) of the chest, abdomen, and pelvis. Clinical factors studied included sedimentation rate, B symptoms, histology, number and location of involved sites, sex, mediastinal involvement, and age. Pretreatment CTs were centrally reviewed in 88 cases for the presence and size of both supradiaphragmatic and infradiaphragmatic lymph nodes, intrinsic spleen lesions, and splenic size. Models were generated that were predictive of any abdominal disease, splenic involvement, extensive splenic involvement, and upstaging at the laparotomy. False-positive and false-negative rates were calculated. RESULTS: For the end point of any abdominal disease, a model based on B symptoms, histology, sedimentation rate, and number and location of involved sites was highly significant (P < .0001). However, the success in predicting abdominal disease in an individual patient was limited: false-negative rate, 26%; false-positive rate, 32%. Highly significant models based on clinical factors and/or radiographic findings were also generated to predict splenic involvement, extensive splenic involvement, and upstaging with laparotomy, but they also had high false-positive and false-negative rates. CONCLUSION: Laparotomy findings cannot be predicted accurately in the majority of patients based on knowledge of CT findings and clinical factors.


Assuntos
Doença de Hodgkin/patologia , Laparotomia , Estadiamento de Neoplasias/métodos , Adolescente , Criança , Pré-Escolar , Árvores de Decisões , Doença de Hodgkin/diagnóstico por imagem , Humanos , Modelos Logísticos , Valor Preditivo dos Testes , Fatores de Risco , Baço/patologia , Tomografia Computadorizada por Raios X
12.
Cancer ; 71(5): 1898-903, 1993 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8448755

RESUMO

BACKGROUND: The prognosis for children with recurrent or resistant malignant solid tumors remains dismal. More effective rescue therapy is needed for these children. METHODS: Between August 1987 and November 1990, 311 children with recurrent or resistant malignant solid tumors were treated by investigators in the Pediatric Oncology Group with intravenous infusions of 2.0 g/m2 of ifosfamide and 100 mg/m2 of etoposide (VP-16) plus mesna as uroprotection three times daily, with courses being repeated every 14-21 days for as long as the patients responded to therapy. RESULTS: Seventy-four percent of the 294 assessable patients entered in the study had metastatic disease and previously had been treated heavily. The complete response/partial response rate was 30%, and the overall response rate was 39.5%. Toxic effects included nephrotoxicity, mild liver dysfunction, neurotoxicity, and myelosuppression. Sixty-eight percent had an absolute neutrophil count (ANC) of less than 500/microliters. In 1606 courses of therapy administered, only 3.6% of patients developed a bacterial infection. Only two patients died of gram-negative sepsis. Four percent of the patients had gross hematuria (> 50 erythrocytes/high-power field), and 18.5% had microscopic hematuria (< 20 erythrocytes/high-power field). Fanconi syndrome developed in eight children. CONCLUSIONS: Ifosfamide/VP-16 is an active combination in children with recurrent malignant solid tumors. Although it was myelosuppressive, the incidence of infection was quite low (3.6%). Mesna was very effective in preventing the development of hematuria.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Etoposídeo/administração & dosagem , Ifosfamida/administração & dosagem , Recidiva Local de Neoplasia/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Criança , Pré-Escolar , Humanos , Lactente
13.
Cancer ; 67(5): 1428-30, 1991 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-1991308

RESUMO

The natural history of Hodgkin's disease in children younger than 4 years of age is unknown. Thirty-eight patients younger than 4 years of age at the time of diagnosis of Hodgkin's disease were treated at the member institutions of the Pediatric Oncology Group. They were found to be predominantly white and male with early-stage disease. Mixed cellularity and nodular sclerosing histologies were most commonly seen and occurred in equal frequency. They responded to therapy extremely well attaining a complete remission rate of 92% to 94%. Even after relapse, they can be successfully retrieved with salvaging therapy.


Assuntos
Doença de Hodgkin , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Pré-Escolar , Terapia Combinada , Feminino , Doença de Hodgkin/patologia , Doença de Hodgkin/terapia , Humanos , Masculino , Estadiamento de Neoplasias , Indução de Remissão
14.
Pediatrics ; 74(1): 86-9, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6588361

RESUMO

Twenty-seven children with various childhood malignancies who were in clinical remission and receiving maintenance chemotherapy were given diphtheria-pertussis-tetanus (DPT) immunizations. Antidiphtheria and antitetanus titers were drawn before and 1 month after immunization. Only one child had no antibody response to either antigen. Two other children failed to develop any detectable antitetanus antibody titer but did mount a normal antibody response to inactivated diphtheria antigen. In fact, most children made good antibody responses to both immunizing antigens, irrespective of the nature of their disease or of the treatment given. These results show that children receiving long-term chemotherapy should not be denied the protection afforded by immunization with nonliving vaccines.


Assuntos
Antineoplásicos/uso terapêutico , Toxoide Diftérico/imunologia , Imunização , Leucemia Linfoide/tratamento farmacológico , Toxoide Tetânico/imunologia , Adolescente , Formação de Anticorpos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Vacina contra Coqueluche/imunologia
15.
Blood ; 60(5): 1096-102, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6289941

RESUMO

Leukemic cells incubated in vitro with 2'-deoxyadenosine (dAdo) plus an inhibitor of adenosine deaminase, 2'-deoxy-coformycin (DCF), show different metabolic responses depending on the histologic and immunologic type of the leukemia. Leukemic cells were obtained from 54 patients with acute lymphoblastic leukemia (ALL), 9 with myeloid or nonlymphoblastic leukemia, 3 with chronic lymphocytic leukemia (CLL), and 3 with lymphoma. There was a wide variation in the LD50, the concentration of dAdo that caused 50% inhibition of the incorporation of 3H-thymidine into cells in the presence of 20 microM DCF. T-cell leukemia specimens were much more sensitive to dAdo than were specimens of pre-B-ALL and null-ALL. In leukemic cells that had been incubated with 14C-dAdo plus DCF, a good correlation was observed between the LD50 and the ratio of 14C-deoxyATP to ATP (correlation coefficient for the fit to a hyperbola = 0.853). The accumulation of deoxyATP by the leukemic cell specimens was correlated best with the activity of ecto-ATPase, less well with cytoplasmic 5'-nucleotidase and deoxyadenosine kinase, and poorly with adenosine deaminase and ecto-5'-nucleotidase. The clinical response to DCF therapy of a patient with T-ALL and another with pre-B-ALL was consistent with the in vitro metabolic response of their cells to DCF and dAdo.


Assuntos
Desoxiadenosinas/farmacologia , Leucemia/metabolismo , Vidarabina/análogos & derivados , Adenosina Desaminase/metabolismo , Adolescente , Nucleotídeos de Desoxiadenina/biossíntese , Humanos , Leucemia Linfoide/metabolismo , Leucemia Mieloide/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucócitos/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Linfoma/metabolismo , Masculino , Nucleotidases/metabolismo , Pentostatina , Timidina/metabolismo , Vidarabina/farmacologia
16.
Hybridoma ; 1(2): 91-8, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6985381

RESUMO

Peripheral blood and/or bone marrow lymphoblasts from 34 children and 11 adults with acute lymphoblastic leukemia (ALL) were evaluated with a monoclonal anti-Ia antibody and a monoclonal anti-pan T-cell antibody (T101) specific for a 65,000-dalton T-cell antigen (T65). Seventy-six per cent of cases were Ia+T65-, 20% were Ia-T65+ and the remaining 4% were Ia-T65-. Anti-Ia and T101 reactivity were mutually exclusive and no Ia+T65+ cases were identified. In childhood ALL, the Ia+T65- phenotype was associated with good prognostic factors and longer median disease-free survival than Ia-T65+ patients whose clinical parameters resembled those characteristic of high-risk T-cell ALL. Included in the Ia-T65+ group were three E-rosette negative cases with clinical features of T-cell disease. Our findings compare favorably with the results of other investigators utilizing polyclonal antisera and suggest that these monoclonal antibodies, which offer the advantages of monospecific standardized reagents, will prove useful in the immunologic characterization of ALL.


Assuntos
Anticorpos Monoclonais , Antígenos de Superfície/análise , Antígenos de Histocompatibilidade Classe II/análise , Leucemia Linfoide/imunologia , Linfócitos/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Antígenos de Superfície/imunologia , Criança , Pré-Escolar , Feminino , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Leucemia Linfoide/sangue , Leucemia Linfoide/diagnóstico , Contagem de Leucócitos , Masculino , Fenótipo , Formação de Roseta
17.
Cancer Res ; 41(7): 2677-82, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6972800

RESUMO

The in vitro effects of deoxyadenosine and an adenosine deaminase inhibitor, deoxycoformycin, on the synthesis of DNA and the metabolism of purines were investigated in human leukemic T-cells. In the presence of 10 microM deoxycoformycin, the synthesis of DNA was completely inhibited by concentrations of deoxyadenosine of 10 microM or greater. In contrast, the synthesis of DNA in normal bone marrow cells was not inhibited in the presence of up to 20 microM deoxycoformycin and up to 10 microM deoxyadenosine. Following incubation of leukemia T-cells with deoxycoformycin and deoxyadenosine, there was a significant rise in the concentration of deoxyadenosine 5'-triphosphate which was accompanied by reductions in the concentrations of adenosine 5'-triphosphate and guanosine 5'-triphosphate, as revealed by high-pressure liquid chromatographic analysis. The effects of deoxycoformycin on T-cell leukemia were examined in vivo. A patient with acute T-cell leukemia in the terminal stage received five daily injections of 250 micrograms of deoxycoformycin per kg. Among the noted changes, most prominent was the drop in the leukocyte count. Initially, the cell count rose from 7,200 cells/microliters on Day 1 to 120,000 cells/microliters on Day 3. On Day 5, the cell count began to decline and reached a nadir of 600 cells/microliter on Day 10. The leukocyte count remained below 1,000 cells/microliter through Day 12. The reduction in cell count was preceded by a decline in the incorporation of [3H]thymidine in the cells, which dropped to negligible amount by Day 7. The other prominent change was a decrease in adenosine deaminase activity in both red cells and leukemic cells. Adenosine deaminase activity of red cells dropped to 5% on Day 4, and that of leukemic cells dropped to 59% on Day 5. In addition, there were considerable alterations in the concentrations of purine metabolites which were characterized by a progressive reduction in the concentrations of total purine metabolites, especially adenosine 5'-triphosphate, and a transient rise in the concentrations of deoxyadenosine 5'-triphosphate, adenosine 5'-monophosphate, and adenosine 5-diphosphate. These findings suggest that treatment with deoxycoformycin may be of therapeutic value for T-cell leukemia. It may provide opportunities for studying the purine metabolism in T-leukemic cells which could lead to better approaches to treatment.


Assuntos
Coformicina/farmacologia , Leucemia Linfoide/tratamento farmacológico , Purinas/metabolismo , Ribonucleosídeos/farmacologia , Linfócitos T/efeitos dos fármacos , Inibidores de Adenosina Desaminase , Células Cultivadas , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Coformicina/análogos & derivados , DNA/biossíntese , Desoxiadenosinas/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Eritrócitos/metabolismo , Humanos , Contagem de Leucócitos/efeitos dos fármacos , Masculino , Pentostatina , Linfócitos T/enzimologia , Linfócitos T/metabolismo
18.
Int J Pediatr Nephrol ; 2(2): 99-101, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7341539

RESUMO

A 15 year old girl presented with weight loss, lymphadenopathy and severe renal failure. A diagnosis of Hodgkin's disease were made by biopsy of a lymph node. Renal biopsy findings included diffuse infiltration of the interstitium by lymphocytes and plasma cells. There was a mild increase in mesangial matrix in the glomeruli. Renal function returned to normal after she received chemotherapy for the Hodgkin's disease. This improvement was associated with a significant decrease in the renal interstitial infiltrate and by a significant decrease in the renal size on intravenous pyelography. It is unusual for patients with Hodgkin's disease to present in renal failure. We are unaware of any previous patient who presented in this manner and who survived with normal renal function. The patient is now apparently free of disease six years after her original illness.


Assuntos
Doença de Hodgkin/diagnóstico , Nefropatias/etiologia , Adolescente , Feminino , Doença de Hodgkin/complicações , Doença de Hodgkin/tratamento farmacológico , Humanos , Rim/patologia , Rim/fisiopatologia
19.
J Natl Cancer Inst ; 65(2): 277-84, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6967527

RESUMO

Biochemical studies suggested that leukemia T-cells have low levels of TTP-catabolizing enzyme activity and are uniquely sensitive to thymidine (dThd). A child with T-cell acute lymphocytic leukemia (ALL), whose peripheral blood lymphoblasts manifested very low TTP catabolic capacity, was treated with 75 g dThd/m2/day by constant iv infusion for two courses of 5 and 8 days. The dThd caused an initial accumulation of peripheral blood blasts in S-phase at the expense of cells in G1, followed by a rapid reversal of this pattern consistent with a block in late G1 and/or early S. Concurrently, a prompt reduction of blasts was found in the peripheral blood. However, dThd treatment neither decreased the number of lymphoblasts in the cerebrospinal fluid (CSF) nor cleared the marrow. No major toxicity was observed, but the effect of dThd on normal marrow elements could not be evaluated in this patient. Blood concentrations of dThd were 1.4-3.0 mM, and concentrations of thymine were in the same range; beta half-life for dThd was 48 minutes. Steady-state CSF dThd was 9% of the simultaneous serum level. Clearance measurements demonstrated that catabolism of dThd was saturated and that renal clearance was a major determinant of total body clearance during high-dose dThd infusion. A good correlation was found between biochemical and cytokinetic parameters and response to dThd for the peripheral blood lymphoblasts. However, dThd did not produce a useful remission in this case of T-cell ALL.


Assuntos
Antineoplásicos , Leucemia Linfoide/tratamento farmacológico , Linfócitos T , Timidina/uso terapêutico , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Ciclo Celular , Pré-Escolar , Avaliação de Medicamentos , Humanos , Infusões Parenterais , Leucemia Linfoide/metabolismo , Masculino , Timidina/farmacologia
20.
Med Pediatr Oncol ; 6(3): 261-77, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-381887

RESUMO

In this study 523 previously untreated patients with acute myelocytic leukemia were randomly allocated to induction therapy with daunorubicin 60 mg/M2 daily X 3, cytosine arabinoside and thioguanine 100 mg/M2 each every 12 hours until marrow hypoplasia was achieved, or a 5-day course of the three drugs with daunorubicin 100 mg/M2 given on dav 1 and cytosine arabinoside plus thioguanine each given at a dose of 100 mg/M2 every 12 hours for five days. All patients received cyclophosphamide 600 mg/M2 followed in 24 hours by hydroxyurea 500 mg/M2 every six hours for four doses monthly for maintenance therapy. Patients were randomized to receive one of three antimetabolite treatments beginning 24 hours after the last dose of hydroxyurea each month for seven days. One such treatment consisted of 6-mercaptopurine 100 mg/M2 daily, another group received 6-thioguanine at the same dose daily, and the third group received 50 mg/M2 of both antimetabolites daily. There were no significant differences in complete response rate, remission duration, or survival among the various treatment groups.


Assuntos
Antineoplásicos/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Adulto , Fatores Etários , Idoso , Antineoplásicos/efeitos adversos , Medula Óssea/efeitos dos fármacos , Ensaios Clínicos como Assunto , Ciclofosfamida/administração & dosagem , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Esquema de Medicação , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Hidroxiureia/administração & dosagem , Leucemia Mieloide Aguda/mortalidade , Masculino , Mercaptopurina/administração & dosagem , Pessoa de Meia-Idade , Remissão Espontânea , Tioguanina/administração & dosagem
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