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1.
J Clin Oncol ; 21(10): 1904-11, 2003 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12743142

RESUMO

PURPOSE: This trial tested the hypothesis that combined androgen suppression (CAS) and whole-pelvic (WP) radiotherapy (RT) followed by a boost to the prostate improves progression-free survival (PFS) by 10% compared with CAS and prostate-only (PO) RT. This trial also tested the hypothesis that neoadjuvant and concurrent hormonal therapy (NCHT) improves PFS compared with adjuvant hormonal therapy (AHT) by 10%. MATERIALS AND METHODS: Eligibility included localized prostate cancer with an elevated prostate-specific antigen (PSA) < or = 100 ng/mL and an estimated risk of lymph node (LN) involvement of 15%. Between April 1, 1995, and June 1, 1999, 1,323 patients were accrued. Patients were randomly assigned to WP + NCHT, PO + NCHT, WP + AHT, or PO + AHT. Failure for PFS was defined as the first occurrence of local, regional, or distant disease; PSA failure; or death for any cause. RESULTS: With a median follow-up of 59.5 months, WP RT was associated with a 4-year PFS of 54% compared with 47% in patients treated with PO RT (P =.022). Patients treated with NCHT experienced a 4-year PFS of 52% versus 49% for AHT (P =.56). When comparing all four arms, there was a progression-free difference among WP RT + NCHT, PO RT + NCHT, WP RT + AHT, and PO RT + AHT (60% v 44% v 49% v 50%, respectively; P =.008). No survival advantage has yet been seen. CONCLUSION: WP RT + NCHT improves PFS compared with PO RT and NCHT or PO RT and AHT, and compared with WP RT + AHT in patients with a risk of LN involvement of 15%.


Assuntos
Antagonistas de Androgênios/administração & dosagem , Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , California , Quimioterapia Adjuvante , Terapia Combinada , Intervalo Livre de Doença , Esquema de Medicação , Humanos , Metástase Linfática , Masculino , Massachusetts , Michigan , Pessoa de Meia-Idade , Terapia Neoadjuvante , Cidade de Nova Iorque , Ohio , Pennsylvania , Modelos de Riscos Proporcionais , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Radioterapia Conformacional , Texas , Resultado do Tratamento , Wisconsin
2.
J Microsc ; 198(Pt 3): 182-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10849196

RESUMO

Complete manipulation by laser light allows precise and gentle treatment of plant cells, subcellular structures, and even individual DNA molecules. Recently, affordable lasers have become available for the construction of microbeams as well as for optical tweezers. This may generate new interest in these tools for plant biologists. Early experiments, reviewed in this journal, showed that laser supported microinjection of material into plant cells or tissues circumvents mechanical problems encountered in microinjection by fragile glass capillaries. Plant protoplasts could be fused with each other when under microscopical observation, and it was no major problem to generate a triple or quadruple fusion product. In the present paper we review experiments where membrane material was prepared from root hair tips and microgravity was simulated in algae. As many plant cells are transparent, it is possible to work inside living, intact cells. New experiments show that it is possible to release by optical micromanipulation, with high spatial resolutions, intracellular calcium from caged compounds and to study calcium oscillations. An example for avian cardiac tissue is given, but the technique is also suitable for plant cell research. As a more technical tool, optical tweezers can be used to spatially fix subcellular structures otherwise moving inside a cell and thus make them available for investigation with a confocal microscope even when the time for image formation is extended (for example at low fluorescence emission). A molecular biological example is the handling of chromosomes and isolated individual DNA molecules by laser microtools. For example, chromosomes can be cut along complex trajectories, not only perpendicular to their long axis. Single DNA molecules are cut by the laser microbeam and, after coupling such a molecule to a polystrene microbead, are handled in complex geometries. Here, the individual DNA molecules are made visible with a conventional fluorescence microscope by fluorescent dyes such as SYBRGreen. The cutting of a single DNA molecule by molecules of the restriction endonuclease EcoRI can be observed directly, i.e. a type of single molecule restriction analysis is possible. Finally, mechanical properties of individual DNA molecules can be observed directly.


Assuntos
Lasers , Micromanipulação , Microscopia Confocal , Células Vegetais , Animais , Cálcio/metabolismo , DNA de Plantas/análise , Gravitropismo , Miocárdio/metabolismo , Plantas/ultraestrutura
3.
Cytometry ; 36(3): 209-16, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10404970

RESUMO

Single-molecule studies in the life sciences often deal with observation or spectroscopy. Studies of reactions are rare, and the light microscope has been used for such experiments only occasionally. In an experimental environment, for example, as is required for most nearfield scanning or electron microscopies, it is difficult to study single-molecule reactions of biological relevance. Therefore, we have developed techniques to study single-molecule reactions with classic (nonscanning) farfield light microscopy. The conversion of nicotinamide adenine dinucleotide (NAD+) and lactate to NADH (a reduced form of NAD+), pyruvate, and H+ catalyzed by a few LDH-1 enzyme molecules has been studied in substrate solutions with different viscosity using the NADH autofluorescence. It is even possible to monitor the progress of the reaction by phase-contrast microscopy via scattering or absorption by product molecules. As an example for a single-molecule reaction with a macromolecule as substrate, the handling and enzymatic cutting of fluorescently stained lambda-DNA is studied. In solutions containing 10 mM magnesium and 66 mM potassium ions at pH 7.9, an individual DNA molecule tends to collapse into a globular structure. When moved through an aqueous solution, it becomes stretched by viscosity drag. After stopping the motion, the molecule collapses and the dynamics of this process can be quantified. When a restriction enzyme is present, sequence-specific cutting can be directly observed in the light microscope. The theoretical restriction pattern, as predicted from the sequence of the molecule, can be generated directly under visual inspection.


Assuntos
DNA Viral/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , NAD/metabolismo , Bacteriófago lambda/genética , Microinjeções , Microscopia de Fluorescência/métodos , NADP/metabolismo , Ácido Pirúvico/metabolismo
4.
Biol Chem ; 379(8-9): 1175-80, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9792451

RESUMO

Lactate dehydrogenase (LDH-1) catalyzes the reaction of lactate and nonfluorescent NAD+ to pyruvate, NADH (fluorescence at lambda em = 455 nm, lambda em = 365 nm) and H+. The injection of highly diluted LDH-1 solution into a drop of substrate solution results in the formation of a bubble of enzyme inside the drop of substrate. At the contact surface between the enzyme solution and the substrate, discrete and statistically distributed zones of increasing fluorescence intensity and different size can be observed after enzyme injection. These zones can be interpreted as clouds of NADH around a single or a few enzyme molecules. The kinetics of the NADH formation in every fluorescent zone, and the size of the zone, can be described by a zero order production combined with a diffusion controlled loss of the reaction's product NADH from the reaction zone. From the dilution of the enzyme solution and from statistical analysis one can conclude that only few enzyme molecules in the center of the fluorescent reaction zones catalyze the NADH formation.


Assuntos
L-Lactato Desidrogenase/metabolismo , Catálise , Ácido Láctico/metabolismo , Microscopia de Fluorescência , NAD/metabolismo , Especificidade por Substrato
5.
Chirurgie ; 122(7): 387-92, 1997.
Artigo em Francês | MEDLINE | ID: mdl-9588056

RESUMO

The authors have reviewed 37 patients aged 64 to 91 years or their charts in the purpose to evaluate the results of surgical treatment of severe acquired contractures of arms hands and legs. They describe the deformations, surgical technique, morbidity, and the results. 4 patients deceased within the first week after surgery; morbidity was very low. The results were satisfactory: nursing was greatly facilitated and pain during nursing care and toilet disappeared, the patients could again seat in a wheel chair. They conclude that this surgery can be very helpful for these disabled patients.


Assuntos
Idoso Fragilizado , Doenças Musculares/cirurgia , Tendões/cirurgia , Idoso , Idoso de 80 Anos ou mais , Braço , Feminino , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Int J Radiat Oncol Biol Phys ; 24(4): 755-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1429101

RESUMO

Between 1979 and 1989, 17 patients with unfavorable bone sarcoma were treated wholly or in part with heavy charged particle irradiation (helium and/or neon ions) at the University of California Lawrence Berkeley Laboratory. The majority of tumors were located near critical structures such as the spinal cord or brain. Gross tumor was present in all but two patients at the time of irradiation. Six patients were treated for recurrent disease. Histologies included osteosarcoma, Ewing's sarcoma, and recurrent osteoblastoma. Four of the osteosarcomata were believed to have been induced by previous therapeutic irradiation for various tumors. Follow-up time since initiation of radiation ranged from 7 to 118 months (median 40 months). The 5-year Kaplan-Maier local control rate was 48%; the corresponding survival rate was 41%. Over half the patients succumbed to distant metastases despite the majority of patients receiving chemotherapy. In this preliminary study, we have shown that heavy charged particle irradiation can be effectively used for control of bone sarcoma. A Phase II trial is warranted to determine optimal treatment for unresectable or gross residual disease.


Assuntos
Neoplasias Ósseas/radioterapia , Sarcoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/mortalidade , Humanos , Lesões por Radiação , Sarcoma/tratamento farmacológico , Sarcoma/mortalidade , Análise de Sobrevida , Falha de Tratamento
7.
Int J Radiat Oncol Biol Phys ; 22(3): 489-94, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1735685

RESUMO

Iododeoxyuridine is a halogenated pyrimidine and non-hypoxic cell radiosensitizer currently being used in clinical trials. The amount of radiosensitization by IdUrd is related to the amount of incorporation of the drug into a cell's DNA. These experiments were carried out in three human tumor cell lines (lung, glioma, and melanoma) in monolayer culture exposed to concentrations of IdUrd from 0.1-10 microM for one and three cell cycles before irradiation to determine incorporation and sensitization as a function of drug exposure. Except for the lung cell line, which required greater than 1 microM IdUrd, these cells demonstrate radiosensitization when exposed to 0.1 microM or greater of IdUrd. Maximum sensitization occurred at 10 microM IdUrd for all the cell lines at three cell cycles. The percent thymidine replacement by IdUrd increased with increasing concentrations, but was cell line dependent. Maximum percent replacement occurred at 10 microM at three cell cycles for all the cell lines: lung = 22.4%, glioma = 32.0%, and melanoma = 39.1%. The relationships between percent thymidine replacement and sensitization are not identical across these human tumor cell lines. If IdUrd is going to be a successful radiosensitizer in clinical trials, sustained plasma levels of 10 microM or greater for at least three cell cycles should be achieved during irradiation. This may be best accomplished with repeated short exposures to IdUrd (three cell cycles or approximately 4 days in these cell lines) every 1-2 weeks during radiation. Measurements of thymidine replacement in a tumor biopsy should be attempted prior to radiation to develop a predictive assay for radiosensitization.


Assuntos
DNA de Neoplasias/metabolismo , Idoxuridina/farmacocinética , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes/farmacocinética , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Idoxuridina/farmacologia , Radiossensibilizantes/farmacologia , Células Tumorais Cultivadas
8.
Int J Radiat Oncol Biol Phys ; 16(5): 1251-5, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2715076

RESUMO

These experiments were designed to find the minimum concentration at which incorporation of and sensitization by IdUrd (Iododeoxyuridine) would occur and the effect of concentrations from .1 to 100 microM for exposures of 8 to 96 hr in cultured V-79 cells exposed to 137Cs gamma rays at 2 Gy per minute. At 0.1 microM thymidine replacement averaged 1% and the SER ranged from 1.1 to 1.28, significant at the 95% level. The maximum thymidine replacement was 49% after 48 hr exposure to 30 microM yielding an SER of 2.7. SER generally peaked after 72 hr of exposure. This cell line has an 8 hr cycle time in our hands and thus optimal sensitization would occur after 9 cell cycles. These ranges need testing in human cells in culture and in Phase I clinical trials.


Assuntos
Idoxuridina/farmacologia , Radiossensibilizantes/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Cricetinae , Idoxuridina/administração & dosagem , Idoxuridina/metabolismo , Tolerância a Radiação , Radiossensibilizantes/administração & dosagem , Radiossensibilizantes/metabolismo , Fatores de Tempo
9.
Cancer ; 60(8): 1847-55, 1987 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-3652011

RESUMO

Thirty-eight cases of optic gliomas seen at the University of California, San Francisco, were reviewed. Two patients died in the postoperative period and were excluded from the follow-up analysis. Twenty-nine cases (76%) involved the optic chiasm, nine (24%) cases were confined to one optic nerve. Most tumors were slow growing and progressive although there were three cases of adult chiasmal gliomas which exhibited unusually aggressive behavior. The three cases are presented in detail. After a mean follow-up period of 9.4 years, the 10-year overall actuarial survival was 87%. Relapse-free survival was 55% at 10 years. Chiasmal tumors had a poorer prognosis compared to optic nerve tumors with 56% of chiasmal tumors recurring versus 22% of optic nerve tumors. Radiotherapy was beneficial in chiasmal gliomas, initially improving vision in 35% (6/17) and decreasing recurrence from 86% (6/7) without radiation therapy to 45% (9/20) with radiation therapy. Optic gliomas are not benign, self-limiting lesions, and therefore require treatment. Radiotherapy is effective in chiasmal gliomas and should be used early in the management of these tumors. No advantage to radiotherapy could be demonstrated for optic nerve gliomas, although the number of these cases analyzed was small.


Assuntos
Neoplasias dos Nervos Cranianos/epidemiologia , Glioma/epidemiologia , Quiasma Óptico , Doenças do Nervo Óptico/epidemiologia , Nervo Óptico , Adulto , Idoso , Terapia Combinada , Neoplasias dos Nervos Cranianos/radioterapia , Feminino , Seguimentos , Glioma/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , São Francisco
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