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1.
Cancer Radiother ; 10(6-7): 444-50, 2006 Nov.
Artigo em Francês | MEDLINE | ID: mdl-16978899

RESUMO

We fully describe an innovative radiotherapy technique called Stereotactic Body Radiation Therapy (SBRT), and explain how this technique is commonly used for clinical purpose at the anticancer center Léon-Bérard (Lyon, France). In this technique, a non-invasive stereotactic body frame is used to locate the tumor site with a great precision. This frame is combined with a system, which enables to track the respiratory motions (Active Breathing Control (ABC) or diaphragmatic compression (DC)) in order to reduce the treatment margins for organ motion due to breathing. Thus, the volume of normal tissues that will be irradiated is considerably reduced. The dosimetry is realized with 3 CT exams performed in treatment conditions. The 3D patient "repositioning" is done with a volume CT acquisition (kV) combined with orthogonal images (kV and MV). The SBRT requires a system to limit the organ motions. Although the ABC seems to be more fastidious for patient, it would enable to use smaller margins than with DC technique. Nevertheless, the ABC is not compatible with volume CT acquisitions, which considerably improve the patient repositioning. In conclusion, the quality of repositioning and the high level of conformation enable to deliver high equivalent doses (>100 Gy) in hypofractionated mode, without increasing the treatment toxicity. The SBRT employs the last technologic innovations in radiotherapy and is therefore considered as a new efficient tool for solid tumors treatment.


Assuntos
Neoplasias/cirurgia , Radiocirurgia/métodos , Desenho de Equipamento , Humanos , Radiocirurgia/instrumentação , Dosagem Radioterapêutica
2.
Cancer Radiother ; 10(8): 559-64, 2006 Dec.
Artigo em Francês | MEDLINE | ID: mdl-16959520

RESUMO

PURPOSE: To analyse a new technique for prostate brachytherapy with permanent Iodine implants characterized by the use of a seed projector after a 3D dosimetric peroperative treatment planning (FIRST technique). PATIENTS AND METHOD: 395 patients have been treated in France with this technique in six radiotherapy centres between November 2002 and December 2005 for a localized prostate cancer. RESULTS: Thirteen patients (3.3%) developped a urinary retention, and respectively 7.8 and 26.5% an acute RTOG grade 3 and 2 toxicity. The 6-weeks IPSS score was equal or lower to 15 in 73% with a 11 median IPSS value. A failure of the loading with the seed-projector, leading to a manual loading of the seeds, occurred in 9 patients (2.3%) in two centres, directly related to the loading procedure with the seed-projector in 5 cases. The median duration of the procedure was reduced by 30 minutes for the patients treated in 2005. CONCLUSIONS: This multicenter study establishes the feasibility of the routine use of a seed projector for permanent iodine 125 prostate implants with an initial tolerance similar to the best results published for other implants techniques.


Assuntos
Braquiterapia/efeitos adversos , Braquiterapia/métodos , Radioisótopos do Iodo/administração & dosagem , Neoplasias da Próstata/radioterapia , Estudos de Viabilidade , Seguimentos , França , Humanos , Imageamento Tridimensional , Masculino , Estadiamento de Neoplasias , Próstata/patologia , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Planejamento da Radioterapia Assistida por Computador , Fatores de Tempo , Retenção Urinária/etiologia
3.
Cancer Res ; 48(24 Pt 1): 7193-9, 1988 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-3056610

RESUMO

Estradiol and triphenylethylene antiestrogen actions have been studied extensively in breast cancer cell lines. However, their effects are still poorly understood on normal human breast cells. We have developed a culture system of normal human breast epithelial (HBE) cells. It has been shown previously that cultured HBE cells were hormone dependent and well adapted for the study of hormone/antihormone actions. However, until now, no data were available on estradiol receptor (ER) in HBE cells. In this study, the presence of ER was demonstrated by (a) whole-cell biochemical assay on breast cells after enzymatic tissue dissociation and (b) an immunocytochemical method using an anti-ER monoclonal antibody both on enzymatically dissociated cells and on 8-day cultured cells. Immunostaining was nuclear and cell positivity was heterogeneous. However, the percentage of positive cells and staining intensity were far greater in the presence of estradiol in the culture, indicating estradiol stimulation of ER. Moreover, HBE cells were used to study the action on cell growth of estradiol versus trans-tamoxifen (TAM), trans-4-hydroxytamoxifen (trans-4OHTAM), and cis-4-hydroxytamoxifen (cis-4OHTAM) alone or added to estradiol. Cell growth was estimated daily by a histometric method and by DNA assay at the end of the 7-day study. When the medium was minimally supplemented with human serum (1%), estradiol stimulated cell growth in a dose-dependent manner at concentrations varying from 10(-9) to 10(-7) M. TAM and trans-4OHTAM clearly inhibited mammary cell division when estradiol was added to the medium and, to a lesser extent, in the absence of estradiol. This inhibitory effect was dose dependent. trans-4OHTAM was 100 times more active than trans-TAM. cis-4OHTAM also clearly inhibited breast cell division at 10(-7) and 10(-6) M concentrations but was 3-fold less efficient than trans-4OHTAM. In conclusion, (a) the presence and estradiol dependence of ER have been demonstrated in HBE cells, which constitute a fruitful model for the study of hormone/antihormone actions, and (b) in these normal cells, estradiol stimulates growth, whereas TAM and the 4OHTAM isomers are potent inhibitors of cell multiplication, as they are in breast cancer cell lines in culture.


Assuntos
Mama/efeitos dos fármacos , Estradiol/farmacologia , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Mama/citologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , DNA/análise , Epitélio/efeitos dos fármacos , Feminino , Humanos , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Isomerismo
4.
Endocrinology ; 114(5): 1483-9, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6232126

RESUMO

Primary cultures of human breast cells prepared from surgical specimens of reduction mammoplasty were used to study the activity of the enzyme 17 beta-hydroxysteroid dehydrogenase (E2DH) which converts estradiol (E2) into its less active metabolite estrone. This study was performed in both epithelial and stromal cells separated, after collagenase digestion of the tissue, on a Percoll gradient, and then cultured as monolayers in Ham's F 10 medium supplemented differently for epithelial cells and fibroblasts. E2DH activity was strikingly higher in epithelial cells than in fibroblasts, since after [3H]E2 incubation (2 nM), 600 fmol/micrograms DNA were metabolized to estrone in epithelial cells after 1 h, whereas an equivalent amount was hardly obtained in fibroblast cultures after 24 h. The affinity and capacity of E2DH were greater in epithelial cells with apparent Michaelis-Menten constant (Km) = 0.6 +/- 0.1 microM and maximum velocity (Vmax) = 250 to 360 pmol/micrograms DNA/h, whereas they were 10 +/- 1 microM and 50 to 70 pmol/micrograms DNA/h, respectively, in fibroblast cultures. Moreover, the E2DH activity was 2 to 5 times higher in epithelial cells cultured in the presence of the progestin medroxyprogesterone acetate, whereas it remained unchanged in fibroblasts cultured under the same conditions. This increase in E2DH activity was dose dependent from 10(-10) to 10(-7) M medroxyprogesterone acetate and inhibited by both actinomycin D and cycloheximide. This system of differential breast cell culture appears to be a fruitful tool for the study of the hormone dependence of normal breast growth and differentiation. Due to the presence of E2DH, epithelial cells are more apt to undergo and to moderate E2 action. Moreover, epithelial cells are a possible site of progesterone modulation of E2DH activity. Therefore, E2DH could be a good marker both for epithelial cells and their hormone dependence.


Assuntos
17-Hidroxiesteroide Desidrogenases/metabolismo , Mama/enzimologia , Mama/citologia , Células Cultivadas , Anticoncepcionais Femininos/farmacologia , Dactinomicina/farmacologia , Relação Dose-Resposta a Droga , Epitélio/enzimologia , Estradiol/farmacologia , Feminino , Fibroblastos/enzimologia , Humanos , Cinética , Medroxiprogesterona/análogos & derivados , Medroxiprogesterona/farmacologia , Acetato de Medroxiprogesterona
5.
J Clin Endocrinol Metab ; 55(3): 428-33, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6954155

RESUMO

In the human endometrium, the presence of the progesterone-dependent enzyme 17 beta-hydroxysteroid dehydrogenase (E2DH) permits the conversion of an active estrogen, estradiol, into a less active one, estrone. This E2DH activity contributes to the antiestrogenic properties of progesterone. In the present study, E2DH activity was assayed in 54 surgically removed fibroadenomas. This benign breast disease was chosen since it offers rather homogeneous epithelial concentrations and still remains close to normal breast tissue from a pathological and hormonal point of view. E2DH activity was highest in fibroadenomas with high epithelial cell density. In addition, in these high epithelial cell density fibroadenomas (n = 18), E2DH activity increased markedly throughout the luteal phase of the menstrual cycle. Thus, it was 3- to 4-fold higher in fibroadenomas removed at the end of the luteal phase (1520 +/- 166 fmol/mg protein.h) than in those obtained during the follicular phase (375 +/- 95 fmol/mg protein.h). In addition, a striking increase in E2DH activity was observed in fibroadenomas from 5 patients treated with oral progestins (4080 +/- 650 fmol/mg protein.h) and 3 patients receiving progesterone topically applied upon the breast (3830 +/- 475 fmol/mg protein.h). E2DH activity, therefore, appears to be an important mechanism involved in the control by progesterone of estradiol action in breast tissue, as it is in the endometrium. It is also a good index of cellular differentiation and progesterone action at the molecular level. It is hypothesized that E2DH activity might be a specific marker of progesterone receptor itself and could be proposed in the evaluation of the hormone dependence of human breast tissue.


Assuntos
17-Hidroxiesteroide Desidrogenases/metabolismo , Adenofibroma/enzimologia , Neoplasias da Mama/enzimologia , Estradiol Desidrogenases/metabolismo , Adolescente , Adulto , Estrona/metabolismo , Feminino , Fase Folicular , Humanos , Cinética , Fase Luteal , NAD/farmacologia , Progestinas/uso terapêutico
6.
J Clin Endocrinol Metab ; 63(5): 1174-80, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2428825

RESUMO

In contrast to cancer cell lines, normal human breast epithelial cells are infrequently studied. Such cells, now routinely cultured in our laboratory from tissue obtained at the time of reduction mammoplasty, were used to study the actions of estradiol (E2), the progestin promegestone (R5020), and the antiprogesterone RU486 on cell growth and progesterone-dependent 17 beta-hydroxysteroid dehydrogenase (E2DH) activity, which is considered good marker of epithelial differentiation as well as progesterone dependency. The studies were carried out using secondary cultures to assure equal initial cell distribution. Cell growth was estimated daily by a histometric method providing a growth index and DNA assay. E2 stimulation of cell growth was not found when the cells were grown in our usual culture medium, but E2 dose-dependent growth stimulation occurred in medium minimally supplemented with serum (1%), insulin; and epidermal growth factor. R5020 inhibited cell growth and stimulated E2DH activity in a dose-dependent manner. RU486 behaved as a pure but low potent progestin agonist concerning E2DH stimulation, but as an agonist with partial antagonist properties concerning cell growth inhibition. In conclusion, E2 stimulated proliferation of human breast epithelial cells in culture, whereas the progestin R5020 inhibited cell multiplication and favored differentiation. The antiprogesterone RU486 had a biphasic effect acting both as progestin agonist and partial antagonist.


Assuntos
17-Hidroxiesteroide Desidrogenases/metabolismo , Mama/efeitos dos fármacos , Progestinas/farmacologia , Adolescente , Adulto , Mama/citologia , Mama/enzimologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , DNA/metabolismo , Estradiol/farmacologia , Estrenos/farmacologia , Feminino , Humanos , Mifepristona , Promegestona/farmacologia , Biossíntese de Proteínas , RNA/biossíntese
7.
J Clin Endocrinol Metab ; 73(1): 8-17, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2045475

RESUMO

The estradiol (E2) and progesterone (P) receptors (ER and PR) were studied in normal human breast epithelial (HBE) cells and fibroblasts cultured separately in our laboratory from surgical reductive mammoplasty samples. Immunocytochemical studies were performed on cytospun cells using the anti-ER antibody H222 Sp gamma and the anti-PR antibodies JZB39 and KD68. A specific immunostaining was observed for ER and PR in HBE cells. This immunostaining was nuclear, varying from cell to cell in positivity and intensity of staining. Moreover, ER and PR immunostaining was hormone-modulated: it increased in E2-treated cells and decreased after addition of the progestin R5020. In fibroblasts, a weak ER immunostaining and a stronger PR immunostaining could be observed; however it was not modified by either E2 or progestogen treatment. Thus, in normal breast epithelial cells, E2 stimulates both its own receptor and PR, whereas the progestin R5020 lowers ER and PR content. In contrast, ER and PR content in normal breast fibroblasts seem to be independent of E2 or P action.


Assuntos
Mama/química , Fibroblastos/química , Receptores de Estradiol/análise , Receptores de Progesterona/análise , Adolescente , Adulto , Células Cultivadas , Epitélio/química , Estradiol/farmacologia , Feminino , Humanos , Imuno-Histoquímica , Promegestona/farmacologia , Receptores de Progesterona/efeitos dos fármacos
8.
J Clin Endocrinol Metab ; 83(2): 667-74, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9467590

RESUMO

The role of PRL in human breast tumorigenesis is not well understood. One of the limitations is the difficulty of accurately measuring PRL receptors (PRLR) in human tissues. We established a quantitative PCR method (Q-PCR) in T-47D human breast cancer cells and applied it to 29 patients, 25 of whom presented with either cancer or fibroadenoma. Four patients underwent a mammoplasty, and normal epithelial cells were cultured before Q-PCR. In T-47D cells, 31 x 10(6) messenger RNA molecules were detected per microgram of total RNA. In all patients, expression of the PRLR gene was detected, varying from 1500 to 1 x 10(6) molecules/microgram of RNA in normal tissues and from 4500 to 34.7 x 10(6) molecules/microgram of RNA in tumors. PRLR expression was always greater in tumor than in normal contiguous tissue and similar in cultured mammary epithelial cells and normal breast tissues. Estradiol and progesterone receptor-negative tumors expressed low levels of PRLR transcripts, similar to normal breast tissue from menopausal women. Immunocytochemical analysis of PRLR confirmed stronger staining in almost all tumor samples compared with normal tissues. A messenger RNA encoding locally produced human PRL was also identified by RT-PCR in every sample tested. Our results confirm PRLR gene expression in all tissues studied, and moreover, indicate that this expression is increased in human breast tumors vs. normal contiguous tissues.


Assuntos
Neoplasias da Mama/química , Mama/química , Expressão Gênica , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Receptores da Prolactina/genética , Adulto , Idoso , Células Cultivadas , Feminino , Humanos , Imuno-Histoquímica , Menopausa , Pessoa de Meia-Idade , Receptores de Estradiol/análise , Receptores de Progesterona/análise , Receptores da Prolactina/análise
9.
FEBS Lett ; 440(1-2): 208-12, 1998 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-9862456

RESUMO

Removal of the catalytic nucleophile Glu134 of the retaining 1,3-1,4-beta-glucanase from Bacillus licheniformis by mutation to alanine yields an enzyme with no glycosidase activity. The mutant is able to catalyze the regio- and stereospecific glycosylation of alpha-laminaribiosyl fluoride with different glucoside acceptors through a single-step inverting mechanism. The main advantage of the mutant as glycosylation catalyst with respect to the kinetically controlled transglycosylation using the wild-type enzyme is that the reaction products cannot be hydrolyzed by the mutant enzyme, and glycosylation yields rise to 90%.


Assuntos
Bacillus/enzimologia , Glucose/análogos & derivados , Glicosídeo Hidrolases/metabolismo , Substituição de Aminoácidos , Domínio Catalítico , Cromatografia Líquida de Alta Pressão , Glucose/metabolismo , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Glicosilação , Concentração de Íons de Hidrogênio , Cinética , Peso Molecular , Solventes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Temperatura
10.
Int J Radiat Oncol Biol Phys ; 48(2): 529-34, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10974472

RESUMO

PURPOSE: Analysis of dose specification of tissue heterogeneities. METHODS AND MATERIALS: Three-dimensional dose distribution analyses of 30 patients with localized prostate cancer were reviewed with and without tissue heterogeneity correction. The number of monitor units for each portal entrance (more than 300 different fields) was calculated and the impact of targeting and number of portal entrances was also integrated. RESULTS: The presence of gas in the rectum induces an overdosage of 0.6%, pubic bone induces an underdosage of -1.5%, and femoral heads are responsible for 6% underdosage. For the treatment as a whole, the underdosage is correlated with targeting techniques and weighting of each portal entrance (range, -0.5% to -3.2%). CONCLUSION: Dose calculation must take into account tissue heterogeneities and more precise guidelines for dose prescription are mandatory for further intercomparison.


Assuntos
Fótons/uso terapêutico , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Algoritmos , Cabeça do Fêmur , Gases , Humanos , Masculino , Guias de Prática Clínica como Assunto , Neoplasias da Próstata/diagnóstico por imagem , Osso Púbico , Dosagem Radioterapêutica , Reto , Tomografia Computadorizada por Raios X
11.
Int J Radiat Oncol Biol Phys ; 48(2): 535-9, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10974473

RESUMO

PURPOSE: Use of conformal therapy techniques increases the number of beams used in order to obtain better conformation of the treated volume to the planning target volume. As the number of beams increases, the number of monitor units (MU) for each beam decreases. In this work we have studied, the influence of low MU on dose and homogeneity. METHODS AND MATERIALS: To study the field symmetry and flatness, films were irradiated. The "dose" for each field was always 60 MU; but it was divided into different segment sizes: 2 segments of 30 MU, 3 segments of 20 MU, and so on up to 12 segments of 5 MU. After being developed, films were scanned and analyzed using a densitometer. The measurements were carried out for three X-ray energies: 6 MV, 10 MV, and 18 MV. RESULTS: Each measurement was repeated twice for each energy, and the results were equal. The means of the symmetry and flatness values obtained for each energy are lower than the commonly accepted limits. CONCLUSION: The dose delivered by adding small segments is equivalent to the dose delivered by a conventional segment with our Philips Linacs SL15 and SL20.


Assuntos
Imagens de Fantasmas , Radioterapia Conformacional/métodos , Dosagem Radioterapêutica , Radioterapia Conformacional/instrumentação
12.
J Endocrinol ; 84(2): 273-80, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7365370

RESUMO

The present paper describes studies conducted to detect and characterize the nuclear receptor for oestrogen in the baboon endometrium. Only 10% of the [3H]oestradiol nuclear receptor complexes were extracted with a 0.5 M-KCl solution. This solubilized receptor migrated as a 4.4S peak during 5-20% sucrose gradient centrifugation. The oestrogen receptor was not bound to oestrogen in the nuclei under normal physiological conditions. Using an unlabelled competitor addition technique with intact nuclei the variation in oestrogen-receptor concentration of baboon endometrium during the menstrual cycle was measured. This concentration increased slightly during the first week of the cycle, being maximal on day 7 before ovulation (2500 molecules/cell), then decreasing gradually, reaching the lowest level (300 molecules/cell) on day 5 after ovulation, where it remained until the end of the cycle.


Assuntos
Endométrio/análise , Menstruação , Papio/metabolismo , Receptores de Estrogênio/análise , Animais , Núcleo Celular/análise , Centrifugação com Gradiente de Concentração , Feminino
13.
J Endocrinol ; 84(2): 261-72, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7365369

RESUMO

A cytosolic oestrogen receptor from baboon endometria was detected and partially characterized. The apparent dissociation constant for oestradiol was 1.5 x 10(-10)--4 x 10(-10) mol/l. Steroids that competed with the [3H]oestradiol binding to the receptor were oestradiol and ethynyloestradiol greater than oestriol greater than oestrone; progesterone, testosterone and corticosterone were not competitors. The [3H]oestradiol-receptor complexes migrated as a 3-3.5S peak during sucrose density-gradient centrifugation when endometrial samples were taken during either the proliferative or the secretory phase. A 7S peak was observed for samples taken at the period of ovulation. A [3H]oestradiol exchange technique was used to detect changes in the receptor concentration during the menstrual cycle. This concentration which was high during the early follicular phase fell sharply before the ovulatory peak of ovarian oestrogens. It remained at a base level during the early secretory phase and then rose during the last days of the cycle to the same concentration as that measured at the beginning of the cycle.


Assuntos
Endométrio/análise , Menstruação , Papio/metabolismo , Receptores de Estrogênio/análise , Animais , Centrifugação com Gradiente de Concentração , Citosol/análise , Estradiol/sangue , Feminino , Progesterona/sangue
14.
Mol Cell Endocrinol ; 174(1-2): 21-30, 2001 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-11306168

RESUMO

We have previously shown that estradiol (E2) increases the growth of normal human breast epithelial (HBE) cells and the antiestrogen 4-hydroxytamoxifen (4-OHT) inhibits estrogen-induced proliferation. These effects of estrogens and antiestrogens on proliferation have also been well documented in breast cancer cells. One mechanism for the antiproliferative effects of antiestrogens is the stimulation of TGFbeta in hormone-dependent MCF-7 and T47D cells. The role of this inhibitory growth factor in normal human breast cells has not been well studied. Accordingly, we measured the amounts of total and active TGFbeta1 and TGFbeta2 by specific E(max) immunoassay (EIA) in culture medium from normal breast cells (epithelial and fibroblasts) and from various ER- and ER+ breast cancer cell lines. We established that HBE cells are sensitive to the antiproliferative effect of TGFbetas, and studied the effect of E2 and 4-OHT, alone or in combination, on the secretion and activation of TGFbetas by HBE cells. HBE cells secrete TGFbeta1 and even more TGFbeta2, and are sensitive to these factors. However, in contrast to MCF-7 cells, TGFbeta secretion in normal breast cells is not regulated by E2 and 4-OHT.


Assuntos
Mama/citologia , Células Epiteliais/metabolismo , Antagonistas de Estrogênios/farmacologia , Estrogênios/farmacologia , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Fator de Crescimento Transformador beta/efeitos dos fármacos , Adolescente , Adulto , Divisão Celular/efeitos dos fármacos , Feminino , Humanos , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/farmacologia , Receptores de Estrogênio/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/patologia
15.
Chest ; 111(5): 1417-23, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9149603

RESUMO

OBJECTIVES OF THE STUDY: Pilot study to assess high-dose rate (HDR) brachytherapy as sole treatment for limited endobronchial non-small cell lung carcinomas. INCLUSION CRITERIA: Proximal non-small cell lung cancer in a not previously irradiated area, with a maximal diameter of 1 cm, no visible tumor on CT scan, lack of other treatment options in patients with severe, chronic respiratory failure, surgery, or external radiotherapy for a previous lung cancer. TREATMENT PROTOCOL: Treatment was based on an escalating dose protocol. Patients received three to five fractions of 7 Gy prescribed at 10 mm from the center of the applicator, once a week. RESULTS: Nineteen patients were included in this trial. The first two patients received three fractions of 7 Gy, the four next patients received four fractions, and the 13 remaining patients were treated with five fractions of 7 Gy. Two months after the end of the procedure, tumors in 15 of 18 evaluable patients (83%) were locally controlled with negative results of biopsies. At 1 year, local control was still obtained in 12 of 16 evaluable patients (75%). With a mean follow-up of 28-months, 1-year and 2-year actuarial survival rates were 78% and 58%, respectively, with a 28-month median survival. One patient with local control died from hemoptysis 12 months after treatment. Two patients suffered from severe necrosis of the bronchial wall; one of them died from hemoptysis. CONCLUSIONS: HDR brachytherapy is an effective treatment for small endobronchial tumors. Late toxicity on the bronchial wall is still too high and was attributed mainly to contact between the catheter and the bronchial mucosa. Exclusive HDR brachytherapy should be restricted to carefully selected patients for whom there is no alternative curative treatment. New bronchial applicators and a lower dose per fraction may reduce the incidence and attenuate the severity of late complications.


Assuntos
Braquiterapia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Análise Atuarial , Biópsia , Braquiterapia/efeitos adversos , Braquiterapia/instrumentação , Braquiterapia/métodos , Brônquios/patologia , Brônquios/efeitos da radiação , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Cateterismo/efeitos adversos , Cateterismo/instrumentação , Causas de Morte , Doença Crônica , Protocolos Clínicos , Desenho de Equipamento , Seguimentos , Hemoptise/etiologia , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Necrose , Seleção de Pacientes , Projetos Piloto , Dosagem Radioterapêutica , Indução de Remissão , Insuficiência Respiratória/radioterapia , Retratamento , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
16.
J Steroid Biochem Mol Biol ; 73(3-4): 171-81, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10925217

RESUMO

The stimulating effect of estradiol (E2) on breast cell growth is well documented. However, the actions of progesterone (P) and its derivatives remain controversial. Additional information is therefore necessary. On a culture system of normal human breast epithelial (HBE) cells, we observed an inhibitory effect on cell growth of a long-term P treatment (7 days) in the presence or absence of E2, using two methods: a daily cell count providing a histometric growth index, and [3H]-thymidine incorporation during the exponential phase of cell growth. A scanning electron microscopy study confirmed these results. Cells exhibited a proliferative appearance after E2 treatment, and returned to a quiescent appearance when P was added to E2. In both studies, P proved to be as efficient as the synthetic progestin R5020. Moreover, the immunocytochemical study of E2 receptors indicated that E2 increases its own receptor level whereas P and R5020 have the opposite effect, thus limiting the stimulatory effect of E2 on cell growth. In the HBE cell culture system and in long-term treatment, P and R5020 appear predominantly to inhibit cell growth, both in the presence and absence of E2.


Assuntos
Mama/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Progesterona/farmacologia , Receptores de Estradiol/metabolismo , Adolescente , Adulto , Mama/metabolismo , Mama/ultraestrutura , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Imuno-Histoquímica , Microscopia Eletrônica de Varredura , Congêneres da Progesterona/farmacologia , Promegestona/farmacologia
17.
J Steroid Biochem Mol Biol ; 39(5A): 769-75, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1958511

RESUMO

Activity of NAD-dependent 17 beta-hydroxysteroid dehydrogenase (E2DH), the enzyme which converts estradiol (E2) into its less active metabolite estrone (E1), has been previously characterized in normal human breast cells in culture and in benign and malignant breast tumors. E2DH activity is far greater in epithelial cells than in fibroblasts. Moreover, it is progesterone dependent in epithelial cells. It was therefore interesting to explore E2DH in the progesterone receptor (PR)-rich T47D cell line as a possible marker of hormone dependence in breast cancer cells. In T47D cells, transformation of [3H]E2 to E1 is limited. The metabolism seems to be preferentially oriented in the way E1----E2 in these cells. However, in the presence of the cofactor NAD the conversion of E2 into E1 increases. Moreover, treatment of T47D cells in culture by the progestin R5020 stimulates E2 to E1 conversion 2- to 3-fold. Stimulation of E2DH (E2----E1) activity reflects both the presence and the operability of PR. This observation underlines the possible interest of E2DH assay in parallel to estradiol receptor and PR to evaluate hormone-dependence of breast cancer.


Assuntos
Estradiol Desidrogenases/metabolismo , Neoplasias da Mama , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Estradiol/metabolismo , Estradiol/farmacologia , Feminino , Humanos , Cinética , Promegestona/farmacologia , Receptores de Estrogênio/análise , Receptores de Esteroides/análise
18.
Brain Res ; 236(1): 227-33, 1982 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-6279237

RESUMO

There is saturable, reversible and specific binding for [3H]prostaglandin E2 (PGE2) to rat brain membranes. This binding is of high affinity, selectively distributed with a maximum in the hypothalamus, the amygdala and the posterior pituitary, and is associated subcellularly with the synaptosomal fraction. This specific PGE2 binding has the characteristics expected for receptors, so opening new perspectives which might clarify the role of PGs in the brain.


Assuntos
Encéfalo/metabolismo , Prostaglandinas E/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Prostaglandina/metabolismo , Sinaptossomos/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Cerebelo/metabolismo , Dinoprostona , Hipotálamo/metabolismo , Masculino , Hipófise/metabolismo , Ratos , Ratos Endogâmicos
19.
J Biotechnol ; 48(3): 209-19, 1996 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-8862000

RESUMO

The synthesis of 4-methylumbelliferyl 3-beta-O-cellobiosyl-beta-D-glucopyranoside (3a) and its use as specific substrate to monitor enzyme activity of 1,3-1,4-beta-D-glucan 4-glucanohydrolases are described. The chromophoric substrate 3a is prepared by a chemoenzymatic approach starting from barley grain, whose beta-D-glucan polysaccharide is degraded down to a tri- and tetrasaccharide by an extracellular extract of recombinant E. coli expressing and secreting Bacillus licheniformis 1,3-1,4-beta-glucanase. The trisaccharide 1 is further chemically transformed into the title compound. Its use as substrate for an enzyme activity assay, the specificity of cleavage, and kinetic parameters are reported. As it undergoes a single glycosidic bond hydrolysis with release of 4-methylumbelliferone, direct UV monitoring of the reaction provides a sensitive kinetic assay of the enzyme action.


Assuntos
Compostos Cromogênicos , Glicosídeo Hidrolases/metabolismo , Biotecnologia , Sequência de Carboidratos , Compostos Cromogênicos/síntese química , Compostos Cromogênicos/química , Glucosídeos/síntese química , Glucosídeos/química , Glicosídeo Hidrolases/análise , Himecromona/análogos & derivados , Himecromona/síntese química , Himecromona/química , Cinética , Dados de Sequência Molecular , Estrutura Molecular , Oligossacarídeos/síntese química , Oligossacarídeos/química , Espectrofotometria Ultravioleta , Especificidade por Substrato
20.
Pathol Res Pract ; 181(3): 273-9, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3748873

RESUMO

Effects of estradiol (E2) and promegestone (R 5020) were tested on primary cultures of epithelial human breast cells prepared from surgical specimens of reduction mammoplasty. Comparative morphological studies were performed by means of transmission and scanning electron microscopy in cells without any hormonal adjunction and in those previously treated with E2 or E2 + R 5020. The results were as follows: In basal medium used as control the majority of epithelial cells, although well-differentiated, remained flat with few microvilli, well-developed Golgi apparatus and rough endoplasmic reticulum, was obvious. R 5020 added with E2 increased differentiation of epithelial cells covered with scarce long and branched microvilli, but reduced the turn-over of young cells. E2 seemed to generate more active proliferation of cells. R 5020 inhibited this effect and induced a higher differentiation of mammary epithelial cells.


Assuntos
Mama/citologia , Estradiol/farmacologia , Norpregnadienos/farmacologia , Promegestona/farmacologia , Mama/efeitos dos fármacos , Células Cultivadas , Células Epiteliais , Epitélio/efeitos dos fármacos , Humanos , Microscopia Eletrônica
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