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1.
Oncogene ; 35(47): 6077-6086, 2016 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-27157619

RESUMO

Notch receptors have been implicated as oncogenic drivers in several cancers, the most notable example being NOTCH1 in T-cell acute lymphoblastic leukemia (T-ALL). To characterize the role of activated NOTCH3 in cancer, we generated an antibody that detects the neo-epitope created upon gamma-secretase cleavage of NOTCH3 to release its intracellular domain (ICD3), and sequenced the negative regulatory region (NRR) and PEST (proline, glutamate, serine, threonine) domain coding regions of NOTCH3 in a panel of cell lines. We also characterize NOTCH3 tumor-associated mutations that result in activation of signaling and report new inhibitory antibodies. We determined the structural basis for receptor inhibition by obtaining the first co-crystal structure of a NOTCH3 antibody with the NRR protein and defined two distinct epitopes for NRR antibodies. The antibodies exhibit potent anti-leukemic activity in cell lines and tumor xenografts harboring NOTCH3 activating mutations. Screening of primary T-ALL samples reveals that 2 of 40 tumors examined show active NOTCH3 signaling. We also identified evidence of NOTCH3 activation in 12 of 24 patient-derived orthotopic xenograft models, 2 of which exhibit activation of NOTCH3 without activation of NOTCH1. Our studies provide additional insights into NOTCH3 activation and offer a path forward for identification of cancers that are likely to respond to therapy with NOTCH3 selective inhibitory antibodies.


Assuntos
Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Mutação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Receptor Notch3/antagonistas & inibidores , Receptor Notch3/genética , Substituição de Aminoácidos , Animais , Linhagem Celular Tumoral , Códon , Modelos Animais de Doenças , Epitopos/química , Epitopos/imunologia , Feminino , Humanos , Camundongos , Modelos Moleculares , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Conformação Proteica , Receptor Notch3/química , Receptor Notch3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Clin Oncol ; 16(3): 897-906, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9508171

RESUMO

PURPOSE: A randomized trial designed to compare mechlorethamine, vincristine, procarbazine, and prednisone (MOPP)/doxorubicin, bleomycin, vinblastine, and daccarbazine (ABVD) (regimen A) with ABVD plus low-dose regional (extended-field) radiation therapy (EF RT) (regimen B) for the treatment of children and adolescents with stages III and IV Hodgkin's disease was conducted by the Children's Cancer Group (CCG-521) from 1986 until 1990. PATIENTS AND METHODS: One hundred eleven eligible patients were randomized, 57 to regimen A and 54 to regimen B. All patients had pathologically verified stage III or stage IV Hodgkin's disease. RESULTS: Overall survival (S) is 87% at 4 years and event-free survival (EFS) is 82%. Patients randomized to ABVD plus EF RT have a 4-year EFS of 87% compared with 77% for patients randomized to MOPP/ABVD (P = .09, two-sided). Patients randomized to ABVD plus EF RT have a 4-year S of 90% compared with 84% for patients randomized to MOPP/ABVD (P = .45, two-sided). Significant prognostic factors in multivariate analysis for EFS are stage of disease, erythrocyte sedimentation rate (ESR) at diagnosis, liver size at diagnosis, and, among stage III patients, the size of the mediastinal mass at diagnosis. The acute toxicities of treatment are largely hematopoietic in nature, whereas acute pulmonary and cardiac toxicities are modest and not limiting. CONCLUSION: The results of this study show that, in advanced-stage Hodgkin's disease in children, equivalent results can be obtained by the addition of either MOPP or low-dose EF RT to the ABVD regimen; whether the addition of either contributes to outcome was not addressed in this study and will require additional testing. It is clear, however, that MOPP chemotherapy can safely be eliminated from front-line combination chemotherapy regimens for advanced Hodgkin's disease in pediatric patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Adolescente , Bleomicina/administração & dosagem , Criança , Terapia Combinada , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Doença de Hodgkin/patologia , Doença de Hodgkin/radioterapia , Humanos , Masculino , Mecloretamina/administração & dosagem , Análise Multivariada , Estadiamento de Neoplasias , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Prognóstico , Modelos de Riscos Proporcionais , Análise de Sobrevida , Vimblastina/administração & dosagem , Vincristina/administração & dosagem
3.
J Clin Oncol ; 8(12): 1971-80, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1700080

RESUMO

Sixty-four patients aged 2 to 18 years with advanced-stage Hodgkin's disease (HD) were treated on a Children's Cancer Study Group (CCSG) pilot toxicity study (521-P). Therapy consisted of 12 courses of Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), bleomycin, vinblastine, and dacarbazine (ABVD), followed by low-dose (2,100 cGy in 12 fractions) regional irradiation (RT). All patients were monitored for toxicity with particular attention to the pulmonary system. Six patients (9%) developed grade 3 or 4 pulmonary toxicity. Three had grade 3 toxicity based solely on changes in carbon monoxide diffusing capacity (DLCO) and remained well for more than 3 years after diagnosis. There was one fatality among the three symptomatic cases. In five cases, toxicity occurred prior to RT. One occurred after seven courses of ABVD, one after nine courses, and three after 10 courses. In one of these five cases, ABVD was stopped. The patient was given nitrogen mustard (mechlorethamine), vincristine, prednisone, and procarbazine (MOPP). This patient subsequently developed recurrence of HD and died of overwhelming sepsis. The other four continued on study and completed their chemotherapy. Three patients had no further bleomycin, and one continued bleomycin at 50% of the assigned dose. They all received mantle RT following chemotherapy, one with a boost dose to the mediastinum to 3,800 cGy and one with added RT to both lungs (1,050 cGy). In the sixth case of pulmonary toxicity, symptoms were first noticed 2 weeks after mantle RT to 3,500 cGy. This patient died of progressive respiratory failure. The event-free survival (EFS) and overall survival is 87% at 3 years. These early results indicate that this therapy is effective in advanced HD in children but has a 9% incidence of acute pulmonary toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bleomicina/administração & dosagem , Bleomicina/efeitos adversos , Causas de Morte , Criança , Pré-Escolar , Terapia Combinada , Dacarbazina/administração & dosagem , Dacarbazina/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Esquema de Medicação , Feminino , Doença de Hodgkin/mortalidade , Doença de Hodgkin/patologia , Doença de Hodgkin/radioterapia , Humanos , Pulmão/efeitos dos fármacos , Masculino , Projetos Piloto , Dosagem Radioterapêutica , Taxa de Sobrevida , Vimblastina , Vincristina/administração & dosagem , Vincristina/efeitos adversos
4.
Trends Endocrinol Metab ; 8(10): 384-90, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18406827

RESUMO

Steroid hormone receptors are ligand-activated transcription factors that enhance or repress gene expression. They act by binding to target sites within the promoters of genes assembled as chromatin. Chromatin structure is modified in response to steroid hormones and represents a critical step in steroid receptor signaling. Recent experiments demonstrate that the progesterone and glucocorticoid receptors are differentially influenced by this arrangement of DNA and histones. One of the most important developments in the steroid hormone receptor field has been the identification of coactivators and cointegrators, some of which are histone acetyltransferases. These proteins appear to play an important role in mediating ligand activation of transcription, although their exact role on chromatin templates is undefined.

5.
Int J Radiat Oncol Biol Phys ; 43(1): 47-55, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9989513

RESUMO

PURPOSE: To compare the efficacy of pion radiation therapy with conventional external beam photon therapy, for the treatment of locally advanced stage T3/4, N0, M0 adenocarcinoma of the prostate. METHODS AND MATERIALS: Two hundred seventeen eligible patients were randomly allocated to either photon or pion therapy. No adjuvant hormone therapy was used. RESULTS: Median follow-up was 42 months (range 2-90). Acute bladder toxicity was worse in the pion arm, p = 0.2, but other acute toxicity did not differ. Late grade 2 toxicity was significantly less in the pion arm (29% at 5 years versus 48%, p = 0.002), but late grade 3 or 4 toxicity did not differ. Clinical local control was not significantly different between treatment arms (64% after 5 years with photons, 56% with pions, p = 0.6). Cause-specific and overall survival also did not differ (p = 0.7). There was a significant delay in time to first failure in the photon arm, largely as a result of decreased biochemical relapse, p = 0.01. A multivariate analysis is presented. CONCLUSION: Pion therapy was well tolerated, with increased acute toxicity and significantly decreased late tissue injury. This contrasts with the late toxicity observed with higher LET particle therapy such as neutron therapy. No improvement in local control with pion therapy was observed.


Assuntos
Adenocarcinoma/radioterapia , Mésons/uso terapêutico , Fótons/uso terapêutico , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional/métodos , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Qualidade de Vida , Dosagem Radioterapêutica
6.
Int J Radiat Oncol Biol Phys ; 37(3): 491-7, 1997 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9112443

RESUMO

PURPOSE: This study attempted to compare within a randomized study the outcome of pion radiation therapy vs. conventional photon irradiation for the treatment of high-grade astrocytomas. METHODS AND MATERIALS: Eighty-four patients were randomized to pion therapy (33-34.5 Gy pi), or conventional photon irradiation (60 Gy). Entry criteria included astrocytoma (modified Kernohan high Grade 3 or Grade 4), age 18-70, Karnofsky performance status (KPS) > or = 50, ability to start irradiation within 30 days of surgery, unifocal tumor, and treatment volume < 850 cc. The high-dose volume in both arms was computed tomography enhancement plus a 2-cm margin. The study was designed with the power to detect a twofold difference between arms. RESULTS: Eighty-one eligible patients were equally balanced for all known prognostic variables. Pion patients started radiation 7 days earlier on average than photon patients, but other treatment-related variables did not differ. There were no significant differences for either early or late radiation toxicity between treatment arms. Actuarial survival analysis shows no differences in terms of time to local recurrence or overall survival where median survival was 10 months in both arms (p = 0.22). The physician-assessed KPS and patient-assessed quality of life (QOL) measurements were generally maintained within 10 percentage points until shortly before tumor recurrence. There was no apparent difference in the serial KPS or QOL scores between treatment arms. CONCLUSION: In contrast to high linear energy transfer (LET) therapy for central nervous system tumors, such as neutron or neon therapy, the safety of pion therapy, which is of intermediate LET, has been reaffirmed. However, this study has demonstrated no therapeutic gain for pion therapy of glioblastoma.


Assuntos
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Mésons/uso terapêutico , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Causas de Morte , Glioblastoma/mortalidade , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Fótons/uso terapêutico , Qualidade de Vida , Planejamento da Radioterapia Assistida por Computador
7.
Pediatrics ; 78(5): 861-5, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3763300

RESUMO

Twenty-three episodes of acute elevation of BP related to renal disease in 13 chronically hypertensive children 2 to 18 years of age were treated with a single oral dose of minoxidil. All except one patient were receiving a diuretic and all but one a beta-blocking agent at the time of minoxidil treatment. The goal of lowering BP to or below the 95th percentile for age within four hours of minoxidil administration was achieved in 14 of 23 treatment episodes. The goal was achieved in nine of 11 (82%) when the dose of minoxidil was greater than or equal to 0.2 mg/kg and in five of 12 (42%) when the dose was less than 0.2 mg/kg (P less than .05). In patients treated with greater than or equal to 0.2 mg/kg of minoxidil, mean systolic and diastolic BP decreased significantly from pretreatment values within one hour. In patients receiving less than 0.2 mg/kg, mean systolic BP was never significantly reduced and mean diastolic BP did not change significantly for two hours. Adverse effects were minimal. The results indicate that minoxidil in a dose of 0.2 mg/kg in combination with a diuretic and beta-blocking agent will lower BP to safe levels in most patients with severe hypertension related to renal disease within four hours with minimal side effects.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Minoxidil/uso terapêutico , Adolescente , Criança , Pré-Escolar , Doença Crônica , Humanos , Hipertensão/fisiopatologia , Falência Renal Crônica/complicações , Minoxidil/administração & dosagem
8.
Leuk Res ; 10(4): 457-9, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3515055

RESUMO

Allogeneic bone marrow transplantation (BMT) produced remission in three patients with Philadelphia-chromosome (Ph1)-positive acute lymphoblastic leukemia (ALL) in relapse. Two patients had remissions which lasted longer than two years. Since the prognosis of Ph1-positive ALL treated with conventional therapy is poor, BMT is indicated in first remission in this disease.


Assuntos
Transplante de Medula Óssea , Leucemia Linfoide/terapia , Cromossomo Filadélfia , Adulto , Doença Enxerto-Hospedeiro/etiologia , Humanos , Leucemia Linfoide/genética , Masculino , Transplante Homólogo
9.
J Thorac Cardiovasc Surg ; 119(6): 1154-61, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10838532

RESUMO

OBJECTIVE: We sought to establish the outcome and optimal therapeutic sequence for patients with nonmetastatic Ewing sarcoma/primitive neuroectodermal tumor of the chest wall. METHODS: Patients 30 years of age or younger with nonmetastatic Ewing sarcoma/primitive neuroectodermal tumor of the bone were randomly assigned to receive vincristine, doxorubicin, cyclophosphamide, and dactinomycin or those drugs alternating with ifosfamide and etoposide. Local control was obtained with an operation, radiotherapy, or both. RESULTS: Fifty-three (13.4%) of 393 patients had primary tumors of the chest wall (all rib). Event-free survival at 5 years was 57% for the chest wall compared with 61% for other sites (P >.2). Ifosfamide and etoposide improved outcome in the overall group (5-year event-free survival, 68% vs 54%; P =.002), and a similar trend occurred in chest wall lesions (5-year event-free survival, 64% vs 51%). Patients with chest wall lesions had more attempts at initial surgical resection (30%) than those with other primary tumor sites (8%, P <.01). The attempt at initial resection for chest wall lesions did not correlate with size. Initial resections at other sites were restricted to smaller tumors. Initial resection resulted in negative pathologic margins in 6 of 16 patients, whereas the delayed resection resulted in negative margins in 17 of 24 patients (P =.05). Although there was no difference in survival by timing of the operation in rib lesions, a higher percentage of patients with initial surgical resection received radiation than those with resection after initial chemotherapy (P =. 13). CONCLUSIONS: Although rib primary tumors are significantly larger than tumors found in other sites, their outcome is similar. We favor delayed resection whenever possible to minimize the number of patients requiring radiation therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/cirurgia , Costelas , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/cirurgia , Adolescente , Adulto , Neoplasias Ósseas/mortalidade , Criança , Terapia Combinada , Intervalo Livre de Doença , Humanos , Sarcoma de Ewing/mortalidade , Resultado do Tratamento
10.
Bone Marrow Transplant ; 7(2): 171-2, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2049562

RESUMO

Two adolescent females with metastatic alveolar rhabdomyosarcoma underwent intensive chemoradiotherapy and bone marrow transplantation, one autologous and one allogeneic. Recurrence was detected in the breasts of both patients, the first at autopsy and the other as the only site of treatment failure. Breast masses after bone marrow transplantation should be thoroughly investigated for metastatic disease in patients with rhabdomyosarcoma.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Neoplasias da Mama/secundário , Neoplasias Pulmonares/patologia , Rabdomiossarcoma/secundário , Adolescente , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Rabdomiossarcoma/cirurgia , Transplante Autólogo , Transplante Homólogo
11.
Bone Marrow Transplant ; 2(1): 27-32, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3332154

RESUMO

Six patients with advanced leukemia and one with severe combined immunodeficiency syndrome received allogeneic bone marrow transplantation (BMT) from HLA haploidentical donors who were compatible for one or two loci on the non-shared chromosome. Methotrexate was used for prophylaxis against acute graft-versus-host disease (GVHD). All patients engrafted but developed moderate to severe acute GVHD, and three patients died. Two leukemic patients relapsed but two others survived and were free of disease 403 and 936 days post-transplant. BMT using related partially matched donors may result in durable engraftment and long-term survivors. The implications of using such donors in expanding the application of BMT are discussed.


Assuntos
Transplante de Medula Óssea , Síndromes de Imunodeficiência/terapia , Leucemia/terapia , Doença Enxerto-Hospedeiro/complicações , Doença Enxerto-Hospedeiro/terapia , Antígenos HLA/imunologia , Histocompatibilidade , Humanos , Doadores de Tecidos , Viroses/complicações
12.
J Steroid Biochem Mol Biol ; 53(1-6): 421-9, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7626491

RESUMO

The ability to respond to small signalling molecules such as steroid hormones is important for many physiological processes. Steroid hormones act through a group of high affinity receptors that regulate transcription by binding to hormone response elements (HREs) located within the promoters of target genes, which themselves are organized with nuclear proteins to form chromatin. To dissect the mechanisms(s) of steroid hormone action we have used the steroid inducible mouse mammary tumor virus (MMTV) promoter as a model system. The MMTV promoter is assembled into a phased array of nucleosomes that are specifically positioned in rodent cells. Induction of transcription by glucocorticoids is accompanied by the appearance of a hypersensitive region in the proximal promoter which allows the hormone dependent assembly of a preinitiation complex including transcription factors such as nuclear factor 1 (NF1) and the octamer transcription factor (OTF). Surprisingly, when introduced by transient transfection, the progesterone receptor (PR) is unable to activate this promoter in vivo, a finding that may result from its inability to alter MMTV promoter chromatin. In an attempt to investigate the failure of the PR to activate the promoter, we have stably introduced the MMTV promoter into human T47D breast cancer cells that express high levels of the PR. In contrast to what has been observed previously in rodent cells, the MMTV templates resident in human breast cancer cells adopt a novel and constitutively open chromatin structure. The constitutively open chromatin structure is accompanied by the hormone independent loading of transcription factors including the PR and NF1. In T47D cells that stably express the glucocorticoid receptor, the MMTV promoter responds to glucocorticoids, but not progestins, and displays glucocorticoid induced restriction enzyme hypersensitivity and transcription factor loading. These findings suggest that the organization of the MMTV chromatin structure is dependent upon the cell type and receptor status of the recipient cell into which the MMTV promoter is stably introduced.


Assuntos
Cromatina/ultraestrutura , Vírus do Tumor Mamário do Camundongo/genética , Regiões Promotoras Genéticas , Transcrição Gênica , Animais , Regulação Viral da Expressão Gênica , Humanos , Camundongos , Nucleossomos/ultraestrutura , RNA Mensageiro/genética , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/metabolismo , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas
13.
Neurosurgery ; 19(1): 104-7, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3748329

RESUMO

The authors report a case of primary Ewing's sarcoma of the petrous bone. The radiological features, including the computed tomographic scan and angiographic findings, are described in detail.


Assuntos
Sarcoma de Ewing/patologia , Neoplasias Cranianas/patologia , Angiografia Cerebral , Pré-Escolar , Feminino , Humanos , Sarcoma de Ewing/diagnóstico por imagem , Sarcoma de Ewing/ultraestrutura , Neoplasias Cranianas/diagnóstico por imagem , Neoplasias Cranianas/ultraestrutura , Tomografia Computadorizada por Raios X
14.
Methods Mol Biol ; 176: 283-96, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11554329

RESUMO

The authors have described three approaches for analyzing the chromatin architecture of a steroid-responsive promoter. Mnase allows one to map the positions of nucleosomes on the target gene. The more sensitive restriction enzyme hypersensitivity procedure permits detection of changes in chromatin architecture upon hormonal stimulation. Additional insight into transcriptional regulation of a gene can be obtained by using the related ExoIII footprinting protocol, which provides complementary data on transcription factor binding to chromatin templates. The use of these in vivo chromatin analysis techniques have provided evidence for a role of chromatin structure in regulation of transcription of steroid-responsive promoters including MMTV (2,7,10,14), tyrosine aminotransferase (15), TR beta A (16-19), and retinoic acid receptor beta (RAR beta) (20).


Assuntos
Cromatina/fisiologia , Vírus do Tumor Mamário do Camundongo/genética , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas , Receptores de Esteroides/metabolismo , Ativação Transcricional , Animais , Humanos
15.
Environ Pollut ; 131(1): 81-91, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15210278

RESUMO

Leaching of three pesticides (isoproturon, chlorotoluron and triasulfuron) and a tracer (bromide) were determined in four contrasting soils ranging in texture from sandy loam to clay. The compounds were applied to undisturbed columns of soil and four columns for each soil were randomly selected and leached with 24-mm equivalent of water at prescribed time intervals (3, 9, 24, 37 and 57 d after application). A rapid decline in leached loads of isoproturon and chlorotoluron as time from application to irrigation increased was observed in all soils. In contrast, triasulfuron and bromide loads only decreased rapidly in the clay soil. Bromide losses decreased with decreasing clay contents of the soil and therefore with a decrease in structural development. Magnitudes of pesticide losses varied from soil to soil, depending on structural development and the organic carbon content. Pesticide degradation experiments on disturbed and undisturbed soil samples showed that the rapid decline of leached loads with time was faster than could be explained by degradation alone. Five physico-chemical processes are put forward to explain the different patterns of pesticide leached loads observed in the soils: (1) relative extent of preferential flow, (2) sorption capacity of the compounds to the different soils, (3) extent of degradation of the compounds in the soil, (4) variation in sorption kinetics between compounds associated with pesticide diffusion into soil aggregates, and (5) protection of the compounds by a combination of intra-aggregate diffusion and the presence of preferential flow pathways.


Assuntos
Monitoramento Ambiental/métodos , Herbicidas/análise , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Solo/análise , Difusão , Modelos Teóricos
16.
J Pediatr Surg ; 23(2): 146-51, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3422682

RESUMO

Recently, much attention has been focused on the role of adjuvant chemotherapy in the treatment of osteosarcoma. Surgery, however, remains the primary modality for the ablation of this disease. In this report, we examine the relationship of various aspects of surgical management of osteosarcoma to prognosis for disease-free survival (DFS) in a randomized study of 234 pediatric patients. Attention is restricted to 166 patients with nonmetastatic disease confined to an extremity and who were randomized to receive one of two chemotherapeutic regimens. No advantage with respect to DFS was attributable to the various aspects of surgical management considered: interval from first symptoms to definitive surgery, surgical sequence, and type of surgery. Only two local recurrences were seen. One occurred in an above knee amputation stump and the other occurred in a patient receiving a tibial allograft. One of these patients died of pulmonary metastases within 6 months of recurrence; the other patient is alive without evidence of disease at last contact after resection of the recurrence followed by chemotherapy.


Assuntos
Neoplasias Ósseas/cirurgia , Osteossarcoma/cirurgia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Terapia Combinada , Doxorrubicina/administração & dosagem , Feminino , Neoplasias Femorais/cirurgia , Humanos , Úmero/cirurgia , Neoplasias Pulmonares/secundário , Masculino , Metotrexato/administração & dosagem , Recidiva Local de Neoplasia/terapia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/secundário , Neoplasias Pélvicas/secundário , Prognóstico , Rádio (Anatomia)/cirurgia , Distribuição Aleatória , Tíbia/cirurgia , Vincristina/administração & dosagem
17.
J Pediatr Surg ; 27(9): 1175-80, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1432524

RESUMO

Forty-nine children and adolescents underwent staging laparotomy in the course of a cooperative group (CCG) study of advanced Hodgkin's disease (HD). The purpose of the study was to evaluate the toxicity of a regimen of 12 cycles of doxorubicin, bleomycin, vinblastine, and imidazole carboxamide (ABVD) plus 2,100 cGy regional irradiation in patients with stage III-IV disease. Review of the biopsies and specimens from these 49 laparotomies identified distinct patterns of abdominal involvement and permitted an evaluation of the importance of different aspects of the staging procedure and an assessment of the value of non-invasive techniques in determining the extent of abdominal disease. The major observations from these studies were: (1) computed tomography (CT) and gallium 67 scans (GA) were specific (few false positives), but not sensitive, indicators of abdominal disease; (2) negative findings at laparotomy in 29 patients permitted a contraction of the abdominal radiation fields with no subsequent abdominal recurrence in these patients; (3) in five patients, stage IV status was established only by laparotomy and open hepatic biopsy; (4) all patients with lower abdominal or pelvic involvement also had upper abdominal node or splenic involvement; (5) involvement of splenic hilar nodes was a sensitive predictor of splenic involvement; (6) disease in the inferior paraaortic nodes accurately predicted the presence of more distal disease, ie, in the iliac or pelvic node groups; and (7) in a limited experience, transposition of the ovaries protected ovarian function from the effects of pelvic irradiation.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doença de Hodgkin/patologia , Laparotomia , Linfonodos/patologia , Estadiamento de Neoplasias/métodos , Adolescente , Biópsia , Criança , Pré-Escolar , Estudos de Avaliação como Assunto , Feminino , Radioisótopos de Gálio , Doença de Hodgkin/diagnóstico por imagem , Humanos , Fígado/patologia , Masculino , Invasividade Neoplásica , Complicações Pós-Operatórias , Cintilografia , Sensibilidade e Especificidade , Baço/patologia , Tomografia Computadorizada por Raios X
18.
Pest Manag Sci ; 57(12): 1127-34, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11802600

RESUMO

Twelve lysimeters with a surface area of 0.5 m2 and a length of 60 cm were taken over mole drains from a Denchworth heavy clay soil and divided into two groups with either a standard agricultural tilth or a finer topsoil tilth. The influence of topsoil tilth on leaching of the herbicide isoproturon and a bromide tracer was evaluated over a winter season. The effect of variations in soil moisture status in the immediate topsoil on leaching of isoproturon, chlorotoluron and linuron was investigated in the following winter season. Here, water inputs were controlled such that lysimeters received 50 mm at a maximum intensity of 2 mm h-1 over a 4-week period with herbicides applied on day 15. Three treatments received the water either all prior to application, all after application, or evenly spread over the 4-week period. Leaching losses of the three herbicides were monitored for a subsequently drainage event. Analysis of covariance showed a significant effect of topsoil tilth and total flow on both the maximum concentrations (P = 0.034) and total losses (P = 0.012) of isoproturon in drainflow. Both concentrations and losses were c 35% smaller from lysimeters with the finer tilth. However, generation of the fine tilth in the field was restricted by a wet autumn and this is not considered a reliable management option for reducing pesticide losses from heavy clay soils. In the second experiment, variation in soil moisture content prior to and after application did not have any significant effect (P < 0.05) upon subsequent losses of the three herbicides to drains.


Assuntos
Brometos/metabolismo , Herbicidas/metabolismo , Resíduos de Praguicidas/metabolismo , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/metabolismo , Água/metabolismo , Silicatos de Alumínio/análise , Argila , Concentração de Íons de Hidrogênio , Linurona/metabolismo , Compostos de Metilureia/metabolismo , Tamanho da Partícula , Compostos de Fenilureia/metabolismo , Estações do Ano , Solo/análise , Fatores de Tempo , Água/administração & dosagem
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