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1.
Hum Reprod ; 22(2): 434-9, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16980507

RESUMEN

BACKGROUND: Levonorgestrel (LNG) consistently prevents follicular rupture only when it is given before the onset of the ovulatory stimulus. As locally synthesized prostaglandin (PG) plays a crucial role in follicular rupture and cyclooxygenase-2 (cox-2) catalyses the final step of PG synthesis, we reasoned that adding a cox-2 inhibitor to LNG would prevent follicular rupture even after the ovulatory process had been triggered by the gonadotrophin surge. METHODS: Forty-one women were divided into two groups. One was treated when the size of the leading follicle was 15-17 mm (n=10) and the other when it was >or=18 mm (n=31). Each woman contributed with one cycle treated with LNG 1.5 mg single dose plus placebo and another treated with LNG + meloxicam (Melox) 15 mg, in a randomized order. Serial blood sampling for the assay of LH and follicular monitoring by transvaginal ultrasound were performed before and after treatment. RESULTS: Follicular rupture failed to occur within the 5-day period that followed treatment in 50 and 70% of cycles treated with LNG + Placebo and LNG + Melox, respectively, in the 15-17 mm group (P=0.15) and in 16 and 39% of cycles treated with LNG + Placebo and LNG + Melox, respectively, in the >or=18 mm group (P < 0.052). The overall proportion of cycles with no follicular rupture or ovulatory dysfunction increased significantly by the addition of Melox to LNG (66 versus 88%, P < 0.012; n=41-matched pairs). CONCLUSIONS: The trend towards increased incidence of no follicular rupture when Melox was combined with LNG suggests that the addition of a cox-2 inhibitor has the potential to improve the contraceptive efficacy of LNG by a pre-fertilization effect.


Asunto(s)
Anovulación/inducido químicamente , Anticonceptivos Sintéticos Poscoito/farmacología , Inhibidores de la Ciclooxigenasa 2/farmacología , Levonorgestrel/farmacología , Tiazinas/farmacología , Tiazoles/farmacología , Adolescente , Adulto , Chile , Anticonceptivos Sintéticos Poscoito/administración & dosificación , República Dominicana , Femenino , Humanos , Meloxicam , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología
3.
Med Eng Phys ; 23(3): 185-94, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11410383

RESUMEN

Total respiratory resistance and elastance were estimated off-line in a sample of 60 patients undergoing mechanical ventilation by means of two regression models in order to analyse and understand a possible physiological mechanism determining differences in inspiration and expiration. The first model considered a single value for resistance and elastance over a whole breathing cycle, whereas the second model considered separate values for inspiratory and expiratory resistance and a single value for elastance. Inspiratory resistance was found to be lower than expiratory resistance, and intermediate values were obtained for resistance estimated over the whole breathing cycle. Student's t-test showed a highly significant difference between these resistance estimates, and principal components analysis demonstrated a significant increase in information when both inspiratory and expiratory resistances were used. Minor differences were found between values of elastance calculated with the two approaches. In an attempt to interpret these experimental results, a lung model incorporating the non-linear viscoelastic properties of the intermediate airways was considered. This model suggested that changes in intermediate airway volume play a significant role in breathing mechanics during artificial ventilation and indicated that inspiratory and expiratory resistance could be useful parameters for locating airway obstruction.


Asunto(s)
Resistencia de las Vías Respiratorias/fisiología , Modelos Biológicos , Respiración Artificial , Adaptabilidad , Cuidados Críticos , Elasticidad , Estudios de Evaluación como Asunto , Humanos , Ventilación Pulmonar/fisiología , Análisis de Regresión
4.
Contraception ; 64(6): 369-76, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11834236

RESUMEN

The objective of this study was to evaluate the contraceptive efficacy and clinical performance of a Nestorone subdermal implant (NES) in the postpartum period. NES (n = 100) and Copper T intrauterine device (T-Cu; n = 100) acceptors initiated contraception at 8 weeks postpartum and were followed at monthly intervals during the first year and at 3-month intervals thereafter. Pregnancy rates, breastfeeding performance, infant growth, bleeding pattern, and side effects were assessed. Blood and milk NES concentration were measured. No pregnancy occurred in 2195 and 2145 woman-months of NES implant and T-Cu use, respectively. No effect of NES on lactation and infant growth and no serious adverse events were observed. Lactational amenorrhea was significantly longer in NES users (353 +/- 20 days) than in T-Cu users (201 +/- 11 days). More NES users (55.8%) experienced prolonged bleedings than did T-Cu users (36.2%). Concentrations of NES in breast milk ranged between 54-135 pmol/liter. The Nestorone implant is a highly effective contraceptive, safe for breastfed infants because the steroid is inactive by the oral route.


Asunto(s)
Anticoncepción , Anticonceptivos Femeninos/administración & dosificación , Lactancia/efectos de los fármacos , Norprogesteronas/administración & dosificación , Adolescente , Adulto , Amenorrea/fisiopatología , Lactancia Materna , Chile , Anticonceptivos Femeninos/metabolismo , Implantes de Medicamentos , Femenino , Estudios de Seguimiento , Humanos , Dispositivos Intrauterinos de Cobre/efectos adversos , Leche Humana/efectos de los fármacos , Leche Humana/metabolismo , Norprogesteronas/efectos adversos , Norprogesteronas/metabolismo , Pacientes Desistentes del Tratamiento , Periodo Posparto/efectos de los fármacos , Factores de Tiempo , Hemorragia Uterina/inducido químicamente , Destete
5.
Int J Cancer ; 86(6): 777-81, 2000 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-10842190

RESUMEN

A variable fraction of anaplastic large-cell lymphomas (ALCLs) exhibits a t(2;5)(p23;q35) translocation that results in expression of the chimeric hyperphosphorylated protein NPM-ALK (p80). Tumor cells expressing NPM-ALK exhibit markedly enhanced proliferative activity, but comparative cellular kinetic studies on ALK(+) (ALK lymphomas) and ALK(-) lymphomas are lacking. The present study showed that ALK(+) lymphomas, detected with the monoclonal antibody ALKc (n = 17), had significantly higher average values for the proliferation-associated parameters mitotic index, ana/telophase index, growth index (x x mitotic index - apoptotic index, assuming x = 3), percentages of Ki-67(+) cells and fraction of cells expressing cyclin A or B or the cell cycle-regulatory protein p34(cdc2) than did ALK(-) ALCLs (n = 15). Whether this intense proliferative activity contributes to the good response to chemotherapy and favorable outcome of ALK(+) ALCLs remains to be assessed in a larger series of patients. Our findings support the notion that ALK(+) and ALK(-) ALCLs are 2 distinct disease entities.


Asunto(s)
Linfoma de Células B Grandes Difuso/patología , Proteínas Tirosina Quinasas/análisis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Quinasa de Linfoma Anaplásico , División Celular , Niño , Ciclina A/análisis , Ciclina B/análisis , Femenino , Humanos , Linfoma de Células B Grandes Difuso/metabolismo , Masculino , Persona de Mediana Edad , Índice Mitótico , Proteínas Tirosina Quinasas Receptoras
6.
Comput Biol Med ; 30(4): 171-89, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10821937

RESUMEN

An approach based on the modified Karhunen-Loéve expansion (MKLE) of constitutive and facultative skin colour data acquired by colorimeters in melanoma patients and healthy control subjects, was used to identify two colour features defining skin-colour-associated risk of melanoma. None of four common statistical classifiers trained on colour features were sufficiently accurate for allowing skin colour alone to be used for classification purposes, though a Bayesian quadratic classifier matched the transformed data well. This study supersedes the indeterminate character of most common clinical criteria based on qualitative factors and, irrespective of the results of classification, provides objective skin colour information for the prevention of melanoma.


Asunto(s)
Melanoma/etiología , Reconocimiento de Normas Patrones Automatizadas , Neoplasias Cutáneas/etiología , Pigmentación de la Piel , Algoritmos , Teorema de Bayes , Estudios de Casos y Controles , Colorimetría , Diagnóstico por Computador , Análisis Discriminante , Humanos , Procesamiento de Imagen Asistido por Computador , Análisis Multivariante , Factores de Riesgo
7.
Melanoma Res ; 8(5): 439-47, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9835458

RESUMEN

A statistical procedure to evaluate melanoma risk in Caucasian subjects on the basis of colorimetric measurement of skin colour and Fitzpatrick phototype is described. One hundred and sixty melanoma patients and 546 randomized healthy subjects of similar age, sex and place of origin were examined in the same period for skin colour using a tristimulus colorimeter and for Fitzpatrick phototype. A clinical score for classification purposes was obtained by statistical discriminant analysis with multivariate data transformation and dimension reduction techniques. A Fisher linear classifier was chosen for its simplicity and robustness in correctly predicting melanoma risk in new subjects. The classification rule was designed to avoid classifying subjects at high risk for melanoma as low risk, i.e. to give a negligible number of false negatives at the expense of more false positives. The procedure is objective and readily adapted to different clinical requirements. This is only a preliminary study but it is hoped that by performing more complex statistical analyses, e.g. neural networks, and adding other parameters (proven risk factors such as number of naevi) the performance will be further improved.


Asunto(s)
Melanoma/etiología , Fenómenos Fisiológicos de la Piel , Pigmentación de la Piel , Estadística como Asunto/métodos , Colorimetría , Femenino , Humanos , Masculino , Análisis Multivariante , Valor Predictivo de las Pruebas , Curva ROC , Factores de Riesgo , Sensibilidad y Especificidad
8.
Comput Biomed Res ; 29(6): 482-93, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9012570

RESUMEN

Analysis of the spatial distributions of objects is fundamental to biomedical image interpretation. Nearest-neighbor (NN) methods are generally used to assess whether objects are arranged at random or in a deterministic manner. Simple standard NN techniques, however, may fail to identify complex spatial organizations. To overcome this problem the present study proposes a NN iterative algorithm that enables deterministic spatial patterns to be detected by identifying the distances between objects for which there is the greatest deviation from randomness and hence the amplitude of the areas of maximum reciprocal influence between objects. The performance of the algorithm is evaluated by applying it to both manufactured and experimental data. The manufactured date example showed that the proposed procedure produced neither false positives or negatives. The method proved to be extremely sensitive, detecting even small deviations from randomness. The experimental analysis was applied to the study of the spatial distribution of apopototic structures in malignant neoplastic tissue. It showed that the apopototic cells and bodies are characterized by a complex spatial pattern, and aggregate closely.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Algoritmos , Interpretación Estadística de Datos , Humanos , Linfoma no Hodgkin/patología , Modelos Estadísticos , Distribución Aleatoria
9.
Contraception ; 54(2): 79-86, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8842583

RESUMEN

The efficacy of a low dose of mifepristone, 5 mg/day for the first 15 days of the menstrual cycle, followed by medroxy-progesterone acetate (MPA), 10 mg/day for the next 13 days, for inhibiting ovulation was assessed in ten volunteers who were treated for three successive cycles. Hormonal determinations in blood and urine samples, ovarian ultrasonography and an endometrial biopsy taken on day 21-24 of the third treatment cycle were used to monitor the cycles. Ovulation was confirmed in 11 of the 30 treated cycles and, in these 11, the LH peak and follicular rupture occurred during MPA treatment periods. Out of 19 anovulatory cycles, 16 had no increase in progesterone levels and another 3 developed a luteinized unruptured follicle. Progestin administration induced secretory changes in the endometrium, but irregular or delayed development was found. Regular withdrawal bleeding occurred in all subjects. These data indicate that the sequential regimen can suppress ovulation while maintaining regular bleeding but increased efficacy is needed for phase II clinical trials.


PIP: The efficacy of a low dose of mifepristone, 5 mg/day for the first 15 days of the menstrual cycle, followed by medroxyprogesterone acetate (MPA), 10 mg/day for the next 13 days, for inhibiting ovulation was assessed in 10 Chilean volunteers who were treated for 3 successive cycles. They were healthy, surgically sterilized women with a mean age of 36.6 years and mean weight of 58.6 kg. Hormonal determinations in blood and urine samples, ovarian ultrasonography and an endometrial biopsy taken on days 21-24 of the third treatment cycle were used to monitor the cycles. Treatment inhibited ovulation during the 3 treatment cycles in 5 women. The regimen was partially effective in 3 women and totally ineffective in another 2 women. Ovulation was confirmed in 11 of the 30 treated cycles, and, in these 11, the luteinizing (LH) peak and follicular rupture occurred during MPA treatment periods. Out of 19 anovulatory cycles, 16 had no increase in progesterone levels and another 3 developed a luteinized unruptured follicle. Among the anovulatory cycles, 3 cycles presented a biphasic hormonal profile. In these 3 cycles the luteal phase progesterone level were much lower than in baseline cycles and they were associated with unruptured follicles. The other 16 cycles had a monophasic hormonal profile with no increase in progesterone levels in spite of a delayed rise in LH level. Progestin administration induced secretory changes in the endometrium, but irregular or delayed development was found. Only 9 post-treatment cycles were followed and 5 of these were ovulatory, 1 of them without a detectable LH midcycle peak. Regular withdrawal bleeding occurred in all subjects. These data indicate that the sequential regimen can suppress ovulation while maintaining regular bleeding, but increased efficacy is needed for phase II clinical trials.


Asunto(s)
Endometrio/efectos de los fármacos , Hormonas/metabolismo , Acetato de Medroxiprogesterona/administración & dosificación , Mifepristona/administración & dosificación , Ovario/efectos de los fármacos , Adulto , Biopsia , Endometrio/fisiología , Estradiol/sangre , Femenino , Humanos , Hormona Luteinizante/sangre , Ciclo Menstrual/efectos de los fármacos , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Ovario/diagnóstico por imagen , Ovario/fisiología , Ovulación/efectos de los fármacos , Progesterona/sangre , Factores de Tiempo , Ultrasonografía
10.
Int J Cancer ; 59(3): 313-8, 1994 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-7927934

RESUMEN

To better comprehend the relationships between cell birth and cell death in neoplastic disorders, the topography of these events needs to be considered. We applied a computerized nearest-neighbor analysis to malignant, diffuse follicular-center-cell lymphomas in order to examine the spatial distribution of pyknotic (apoptotic) cells/bodies (A) and mitotic figures (M) in relation to capillaries (C) and venules (V). The results revealed a complex dispersion pattern, with significant aggregations of A and M, in addition to an even greater random distribution component. The greatest clustering displayed by A was around capillaries (A-C, 42% reduction of object frequency between the first and second distance class), followed by A-A (33%), A-V (24%) and A-M (12%). Additional values for mitotic figures were: M-M (45%), M-V (33%) and M-C (22%). These findings may reflect the relative importance of inherent properties of the neoplastic and host factors, respectively, in the regulation of cell birth and cell death rates.


Asunto(s)
Linfoma de Células B Grandes Difuso/patología , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Capilares/patología , Femenino , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , Mitosis , Análisis de Regresión
11.
Hum Reprod ; 8(11): 1828-34, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8288745

RESUMEN

High endometrial receptivity has been achieved with physiological oestradiol and progesterone replacement cycles in women with ovarian failure. To understand whether different protocols using the oral route or the transdermal route can influence the endometrial maturation and the regulation of sex steroid receptors, we studied 33 women with ovarian failure treated by two commonly used protocols and assessed endometrial receptivity using light microscopy, scanning electron microscopy and immunohistochemistry for oestrogen and progesterone receptors on biopsies taken to include different periods of the luteal phase. The morphology in these patients was similar to that observed in women with normal ovulatory cycles, indicating that the morphological response is not dependent on the type of oestradiol, oral or transdermal, in the replacement cycles as compared to the endogenous oestradiol in the menstrual cycle. The relative distribution of steroid receptors between the epithelium and stroma varies similarly to that observed during the luteal phase of the menstrual cycle. These results confirm the role of progesterone, especially the importance of the number of days of exposure to it, in the disappearance of steroid receptors from endometrial glands. These observations give a better understanding of endometrial receptivity around the time of presumed implantation and confirm clinical results concerning the best timing of oocyte transfer.


Asunto(s)
Endometrio/fisiopatología , Estradiol/uso terapéutico , Enfermedades del Ovario/tratamiento farmacológico , Progesterona/uso terapéutico , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Endometrio/patología , Estradiol/administración & dosificación , Estradiol/sangre , Terapia de Reemplazo de Estrógeno , Femenino , Humanos , Inmunohistoquímica , Microscopía Electrónica de Rastreo , Enfermedades del Ovario/patología , Enfermedades del Ovario/fisiopatología , Progesterona/administración & dosificación , Progesterona/sangre
12.
Fertil Steril ; 59(6): 1179-86, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8495762

RESUMEN

OBJECTIVE: To analyze the effects of clomiphene citrate (CC) on cervical mucus (CM) and endometrial morphology independently of hormonal changes encountered when CC is administered for ovulation induction. DESIGN: Volunteers whose ovarian functions were temporarily suppressed (n = 18) by a long-acting GnRH agonist and 6 women of similar age suffering from premature ovarian failure (POF) received E2 and P. Half of the women also received CC (50 mg/d, days 2 to 6). SETTING: Tertiary University Institution, Hôpital A. Béclère. PATIENTS, PARTICIPANTS: Eighteen volunteers suffering from infertility not related to a uterine cause and 6 women of similar age suffering from POF. MAIN OUTCOME MEASURE: Plasma gonadotropins, E2, and P were measured at baseline to confirm that the ovaries were inactive and twice weekly during physiological E2 and P replacement. Cervical mucus was analyzed on day 14 and scored from 0 to 15. Endometrial biopsies were obtained on replacement days 20 and 24 for conventional histology and immunocytochemistry analysis of estrogen receptors and progesterone receptors (PR). Premature ovarian failure women whose results have been previously published served as controls for day 20 biopsies. RESULTS: Cervical mucus scored lower in women who received CC (5.5 +/- 3.2) than in controls (13.6 +/- 4.7, mean +/- SEM). On day 20, endometrial findings were similar in women treated with CC and in controls. On day 24, specimens showed a significant delay in endometrial maturation in women treated with CC. On day 24, only staining for PR selectively persisted in endometrial stroma, and no difference was observed between women who received CC and controls. CONCLUSION: Our results indicate that CC significantly alters CM quality and late luteal phase endometrial morphology despite physiological levels of plasma E2 and P. Hence, clinicians should monitor E2 levels when using CC, and caution should be exerted when supraphysiological levels of E2 are not present to counterbalance the effects of CC on the CM and the endometrium.


Asunto(s)
Moco del Cuello Uterino/efectos de los fármacos , Clomifeno/farmacología , Endometrio/efectos de los fármacos , Estradiol/sangre , Inducción de la Ovulación , Progesterona/sangre , Pamoato de Triptorelina/análogos & derivados , Adulto , Biopsia , Endometrio/patología , Estradiol/farmacología , Femenino , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/farmacología , Humanos , Progesterona/farmacología
14.
Int J Cancer ; 52(2): 202-7, 1992 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-1521909

RESUMEN

Histologically diagnosed, or in part questionable, malignant pleomorphic peripheral T-cell lymphomas (pPTCLs, n = 16) and mixed-cellularity Hodgkin's disease (MCHD, n = 12) were objectively compared by the use of combined immunohistochemistry on paraffin sections, test-point analysis of tissue components, and semi-automated nuclear morphometry on semi-thin resin sections. Classical, qualitative histomorphological distinction of these sub-types of lymphomas proved to be valid and is probably still the best method. Quantitative discriminant features, in order of decreasing significance, were: (i) expression by large atypical cells (LACs) of CD45R0, CD43 and CD45 in pPTCLs, and of CD30 and CD15 in MCHD; (ii) means and standard deviations (SDs) of LAC nuclear-profile areas (greater in MCHD than in pPTCLs); (iii) expression of CD3 by LACs in pPTCLs; (iv) prominence of small lymphoid cells in MCHD; (v) higher percentage of medium-sized lymphoid cells in pPTCLs; and (vi) higher SDs of nuclear-profile circularity factor of small lymphoid cells in MCHD. The medians of the largest nucleolar profile areas in LACs per field did not differ in pPTCLs and MCHD, but dispersion of individual values towards higher levels was significantly greater in the latter. Stepwise discriminant analysis of test point and nucleometric variables that best distinguished pPTCLs from MCHD revealed considerable overlaps, and questionable cases tended to be intermediate between the two. In conclusion, our results confirm and expand the notion of intra-group heterogeneity, with indistinct borders and the existence of intermediate phenotypes between these two taxonomic categories of malignant lymphomas.


Asunto(s)
Núcleo Celular/patología , Enfermedad de Hodgkin/patología , Linfoma no Hodgkin/patología , Linfoma de Células T Periférico/patología , Adolescente , Adulto , Anciano , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , Fenotipo
15.
J Clin Endocrinol Metab ; 74(2): 322-31, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1730810

RESUMEN

To study the role of luteal estradiol (E2), we interrupted the supply of E2 during the luteal phase of E2 and progesterone (P) replacement cycles. Thirty-one women, aged 26-37 yr, with absent or inactive ovaries received three different treatment regimens: group I (n = 11) received transdermal E2 and vaginal P according to a protocol designed to approximate levels of estrone (E1), E2, and P seen during the menstrual cycle. Groups II (n = 11) and III (n = 9) received identical treatments, except that in group II no E2, and in group III no E2 or P, was administered after day 15. Endometrial biopsies were obtained on days 20 and 24 in groups I and II, and on days 14 and 20 in group III. In group I, plasma E1 and E2 reached menstrual cycle levels, whereas in groups II and III, discontinuation of the E2 supply on day 15 resulted in a prompt decrease to castrate levels of plasma E1 and E2. In groups I and II, menopausal FSH and LH levels decreased to 26 +/- 6 and 30 +/- 7 IU/L, respectively, on day 13 (mean +/- SEM). In group I, administration of E2 and P starting on day 15 further lowered plasma gonadotropin levels. In group II, administration of P only failed to induce a similar decrease in plasma FSH and LH. No uterine bleeding occurred before day 25 in women of groups I or II, while women of group III bled within 2 days of E2 withdrawal. Endometrial biopsies were similar in groups I and II. Histological features were characteristic of early and late luteal phases on days 20 and 24, respectively. Endometrial maturation assessed by estrogen and progesterone receptors identified by immunocytochemistry showed the typical distribution seen on day 24 of the menstrual cycle with no difference between groups I and II. We conclude that in women deprived of ovarian function, administration of P only after 14 days of E2 priming prevented uterine bleeding and induced normal secretory transformations of the endometrium, but failed to suppress plasma gonadotropins.


Asunto(s)
Cuerpo Lúteo/fisiología , Endometrio/patología , Estradiol/uso terapéutico , Hormona Folículo Estimulante/sangre , Hormona Luteinizante/sangre , Insuficiencia Ovárica Primaria/tratamiento farmacológico , Progesterona/uso terapéutico , Administración Cutánea , Administración Intravaginal , Adulto , Biopsia , Estradiol/administración & dosificación , Estradiol/sangre , Estrona/sangre , Femenino , Humanos , Insuficiencia Ovárica Primaria/patología , Insuficiencia Ovárica Primaria/fisiopatología , Progesterona/administración & dosificación , Progesterona/sangre , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis
16.
Fertil Steril ; 56(3): 440-5, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1894021

RESUMEN

OBJECTIVE: To assess the effect of gonadotropin-releasing hormone antagonist Nal-Glu administration in the luteal phase and the potential rescue by exogenous human chorionic gonadotropin (hCG) of corpus luteum (CL) after antagonist treatment. DESIGN: We studied the dose of Nal-Glu required for luteolysis and subsequently we coadministered low doses of hCG for 3 consecutive days either simultaneously to Nal-Glu administration (n = 5), or 48 (n = 5), or 72 hours (n = 5) later. Six additional participants received pharmacological doses of hCG 48 hours after the luteolytic dose of Nal-Glu. SETTING: Participants were studied in Clinique Endocrinologique, Nantes, and in Service d'Endocrinologie, Hôpital Bicêtre, Le Kremlin Bicetre, France. PARTICIPANTS: Twenty-nine normal young women (ages 20 to 35) were studied. INTERVENTIONS: None. MAIN OUTCOME MEASURE: Measurements of follicle-stimulating hormone, luteinizing hormone (LH), estradiol, Progesterone (P) levels were performed by radioimmunoassay before, during, and after the various treatment regimens. RESULTS: Complete luteolysis occurred in women who received 10 mg of Nal-Glu daily on days 4 and 5 after the LH surge. The coadministration of Nal-Glu and hCG overrode the effect of the antagonist (P = 48.8 +/- 22.5 versus 60.8 +/- 3.1 nmol/L in controls treated with hCG alone [NS]). When hCG treatment was started 48 hours after Nal-Glu, a partial luteolysis occurred (P = 33.8 +/- 10.9 versus 117 +/- 12.9 nmol/L, P less than 0.01). When hCG was started 72 hours after Nal-Glu, a complete luteolysis occurred (P = 5.8 +/- 2.05 versus 36.2 +/- 0.6 nmol/L, P less than 0.01). Higher doses of hCG (1,500 or 5,000 IU) administered 72 hours after Nal-Glu resulted in a significant rescue of CL function (P = 37.7 +/- 4.8 and P = 43.8 +/- 22.2 versus 74.5 +/- 19.8 and 130.2 +/- 14.3 nmol/L, P less than 0.05), respectively. CONCLUSIONS: These results confirm the LH dependence of CL function. The suppression of CL LH support for 72 hours induced a compromise of the CL nonreversible by low doses of hCG mimicking early pregnancy but reversible with pharmacological doses.


PIP: Researchers studied 29 women 20-35 years old at endocrinology clinics in Nantes and Kremlin Bicetre, France to determine if administering human chorionic gonadotropin (hCG) in addition to the pulsatile gonadotropin releasing hormone antagonist called Nal-Glu would rescue corpus luteum (CL) function. The study consisted of 3 parts: single and repeated administration of Nal-Glu; administration of Nal-Glu and low doses of hCG; and administration of Nal-Glu and pharmacological doses and hCG. The results showed that suppressing the release of luteinizing hormone (LH) for at least 3 days caused luteolysis, but small doses of exogenous hCG did not rescue CL function. On the other hand, if suppression lasted only 2 days, small doses of hCG partially rescued CL function. Nevertheless most participants who experienced suppression for at least 3 days had a spontaneous recovery of CL function, perhaps because suppression did not persist long enough to cause complete luteolysis. 2 injections of Nal-Glu on days 4-5 of the luteal phase did, however, suppress LH support for 72 hours thereby inducing complete luteolysis. 1 woman did not experience complete luteolysis though. Higher doses of hCG did rescue CL function, albeit incompletely. In conclusion, Nal-Glu administration progressively damages CL dose of hcg which maintains CL function may be reached if implantation occurs within 3 days after administration of the antagonist. Therefore it is questionable if hCG can be used as a postcoital contraception.


Asunto(s)
Gonadotropina Coriónica/administración & dosificación , Cuerpo Lúteo/efectos de los fármacos , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Adulto , Gonadotropina Coriónica/farmacología , Cuerpo Lúteo/fisiología , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/farmacología , Humanos
17.
Baillieres Clin Obstet Gynaecol ; 5(1): 107-15, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1855335

RESUMEN

Uterine oestrogen (ER) and progesterone (PR) receptors are subject to fine hormonal control by oestradiol and progesterone. In order to assess the role of ER and PR measurement in the evaluation of endometrial maturation, both receptors were studied by immunocytochemical techniques using monoclonal antibodies during the menstrual cycle, and in women with inactive ovaries treated by different regimens of hormonal substitution with oestradiol and progesterone. During the normal menstrual cycle, the concentrations and distribution of ER and PR changed markedly. During the mid follicular period (days 7-8), a small proportion of stromal and glandular cells stained positively for PR while staining for ER was more intense and more frequent. During the late follicular phase and early luteal period (days 9-19), the staining for PR increased markedly in glandular cells. During the mid and late luteal phase (days 21-27), ER and PR staining disappeared in glandular cells. Thus, while oestradiol increases the staining for ER and PR in both glands and stroma, progesterone decreases ER and PR staining in the glands in a dramatic fashion. These variations, especially the disappearance of PR under the effect of progesterone, are potentially useful for studying the cumulative effect of progesterone on endometrial maturation. This was confirmed in anovulatory women, where a late luteal phase aspect was observed, i.e. the absence of a reduction in ER and PR in glandular cells. In women with ovarian failure, the disappearance of ER and PR in glandular cells is correlated with the duration of progesterone therapy.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Endometrio/química , Receptores de Estradiol/análisis , Receptores de Progesterona/análisis , Adolescente , Adulto , Anticuerpos Monoclonales , Arterias/química , Endometrio/fisiología , Femenino , Humanos , Técnicas para Inmunoenzimas , Fase Luteínica/fisiología , Ciclo Menstrual/metabolismo , Enfermedades del Ovario/tratamiento farmacológico , Enfermedades del Ovario/metabolismo , Útero/irrigación sanguínea
18.
J Biomed Eng ; 11(1): 43-7, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2927099

RESUMEN

A sensitivity analysis study has been performed on a seven-parameter model of the systemic vascular bed in order to obtain structure reductions appropriate for simulation and estimation. This analysis considers separately the systolic and diastolic transfer functions between arterial and venous pressures in order to divide a non-linear problem in two distinct linear problems. The results obtained refer to nominal parameter values corresponding to normal circulatory conditions in man and supply guide-lines for an application-oriented selection of reduced models. Simple resistance-compliance models are preferred because the inertial effects appear to have only slight influence. In particular, the choice of a five-parameter model seems to be convenient for simulation purposes. An additional structure reduction is suggested to reach reliable results in parameter estimation problems. The resulting model is characterized by three elements: peripheral resistance, arterial compliance and venous compliance.


Asunto(s)
Circulación Sanguínea , Simulación por Computador , Modelos Cardiovasculares , Presión Sanguínea , Adaptabilidad , Resistencia Vascular
19.
Cancer ; 58(11): 2512-8, 1986 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-3768843

RESUMEN

Although 60% of Stage I renal carcinoma patients die from tumor within 5 years postoperatively, a considerable percentage survive that period. Nuclear grading can help to predict the outcome, but many of the patients are Grade 2, and the prognosis of this subclass is uncertain. Therefore, nuclear morphometry was carried out in 41 patients with Stage I renal cell carcinoma. Of these, 24 died within 5 years and 17 have survived that period. Using a mean nuclear area of 32 micron 2 as the decision threshold, none of the 24 short-term survivors are below that threshold and three of the long-term survivors exceed that value (18% false-positives) (99% confidence limit). Separate analysis with sets for learning and testing and Grade 2 patients gave similar results. The results show the essential prognostic value of morphometry in this set of patients with Stage I renal cell carcinoma.


Asunto(s)
Carcinoma de Células Renales/ultraestructura , Núcleo Celular/ultraestructura , Neoplasias Renales/ultraestructura , Adulto , Anciano , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/cirugía , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Nefrectomía , Pronóstico , Estadística como Asunto
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