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1.
Cancer Radiother ; 23(5): 401-407, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31351809

RESUMEN

PURPOSE: The purpose of this study was to describe the adjuvant management of high grade uterine sarcoma and highlight prognostic factors for overall survival and progression-free survival. MATERIAL AND METHODS: Between 01/2000 and 01/2015, 91 patients undergoing surgery were presented at the multidisciplinary team meeting of our institution. The type of surgery, the anatomopathological features, adjuvant treatments, dates and sites of recurrence were collected. The prognostic value of the various factors was evaluated with the multivariate Cox model. RESULTS: A total of 50 women with uterine sarcoma were identified and lesions included 43 leiomyosarcomas (86%) and seven high grade sarcomas (14%). Eighteen patients received adjuvant pelvic radiotherapy (36%) and six adjuvant systemic therapy (12%). The median follow-up time was 63 months. Thirty-nine patients (78%) had a recurrence: 22 had only metastatic recurrence (58%), two had isolated pelvic recurrence (5%) and 15 had pelvic and metastatic recurrence (38%). Adjuvant radiotherapy was associated with survival without pelvic recurrence in univariate analysis (P=0.005, hazard ratio [HR]=0.15); age greater than 55 years and adjuvant radiotherapy were associated with metastatic free survival in multivariate analysis (P=0.015, HR=2.37, and P=0.013, HR=0.41 respectively) CONCLUSION: According to the results of our series, there is a benefit of radiotherapy after surgery in terms of local control of uterine sarcoma. It is necessary to identify the subgroup of patients who will benefit from an adjuvant radiotherapy in order to provide them with more optimal care.


Asunto(s)
Radioterapia Adyuvante , Neoplasias Uterinas/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Braquiterapia , Quimioterapia Adyuvante/estadística & datos numéricos , Terapia Combinada , Femenino , Humanos , Histerectomía , Estimación de Kaplan-Meier , Leiomiosarcoma/tratamiento farmacológico , Leiomiosarcoma/radioterapia , Leiomiosarcoma/cirugía , Escisión del Ganglio Linfático , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/prevención & control , Pronóstico , Supervivencia sin Progresión , Modelos de Riesgos Proporcionales , Radioterapia Adyuvante/estadística & datos numéricos , Sarcoma , Neoplasias Uterinas/tratamiento farmacológico , Neoplasias Uterinas/cirugía
2.
Eur J Surg Oncol ; 43(4): 689-695, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27889197

RESUMEN

BACKGROUND: Totally implantable venous access port systems are widely used in oncology, with frequent complications that sometimes necessitate device removal. The aim of this study is to investigate the impact of the time interval between port placement and initiation of chemotherapy and the neutropenia-inducing potential of the chemotherapy administered upon complication-related port removal. PATIENTS AND METHODS: Between January 2010 and December 2013, 4045 consecutive patients were included in this observational, single-center prospective study. The chemotherapy regimens were classified as having a low (<10%), intermediate (10-20%), or high (>20%) risk for inducing neutropenia. RESULTS: The overall removal rate due to complications was 7.2%. Among them, port-related infection (2.5%) and port expulsion (1%) were the most frequent. The interval between port insertion and its first use was shown to be a predictive factor for complication-related removal rates. A cut-off of 6 days was statistically significant (p = 0.008), as the removal rate for complications was 9.4% when this interval was 0-5 days and 5.7% when it was ≥6 days. Another factor associated with port complication rate was the neutropenia-inducing potential of the chemotherapy regimens used, with removal for complications involved in 5.5% of low-risk regimens versus 9.4% for the intermediate- and high-risk regimens (p = 0.003). CONCLUSION: An interval of 6 days between placement and first use of the port reduces the removal rate from complications. The intermediate- and high-risk for neutropenia chemotherapy regimens are related to higher port removal rates from complications than low-risk regimens.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Infecciones Relacionadas con Catéteres/epidemiología , Remoción de Dispositivos/estadística & datos numéricos , Falla de Equipo/estadística & datos numéricos , Migración de Cuerpo Extraño/epidemiología , Neoplasias/tratamiento farmacológico , Complicaciones Posoperatorias/epidemiología , Dispositivos de Acceso Vascular , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Obstrucción del Catéter/estadística & datos numéricos , Niño , Preescolar , Femenino , Hematoma/epidemiología , Humanos , Incidencia , Lactante , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neutropenia/inducido químicamente , Estudios Prospectivos , Implantación de Prótesis , Trombosis/epidemiología , Adulto Joven
3.
Surg Endosc ; 28(9): 2713-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24789127

RESUMEN

BACKGROUND: Chemoradiation therapy (CRT) has become the mainstay of locally advanced cervical carcinomas (LACC). However, the price to pay is a significant rate of both early and late colo-rectal toxicities, which may impact on survivors' quality of life. To reduce the incidence of such complications, we suggest a simple technique of pelvic radioprotection. MATERIALS AND METHODS: An omental flap is created which is placed to fill the Douglas pouch to both increase the space between rectum and uterine cervix and prevent small bowel to fall in and to be exposed to radiation. In addition, a long sigmoid loop is retracted and fixed in the left paracolic gutter to prevent its irradiation as well. RESULTS: From May 2011 to May 2012, 51 successive LACC patients were offered this procedure in addition of a laparoscopic staging. All but 2 with too small an omentum benefitted from omentoplasty, while sigmoidopexy was performed in all but one patient with a long and free sigmoid loop. No immediate adverse effect was observed. The volume of retro-uterine omental flap averaged 7.17 ± 3.79 cm(3). Sequential measurements of the utero-rectal space throughout CRT duration showed a real and durable increase in the distance between these organs, resulting in a drop in the dose of irradiation to recto-sigmoid. With 10 ± 4.5-month median follow-up, we did not observe any rectal or small bowel early or late adverse effects of CRT. CONCLUSIONS: Although this series is preliminary, this simple procedure, feasible by laparoscopy (or laparotomy), seems effective to prevent recto-sigmoid as well as small bowel from radio-induced complications due to pelvic CRT.


Asunto(s)
Quimioradioterapia/métodos , Laparoscopía/métodos , Neoplasias del Cuello Uterino/terapia , Adulto , Anciano , Colon Sigmoide/patología , Femenino , Humanos , Intestino Delgado/patología , Persona de Mediana Edad , Epiplón , Pelvis , Estudios Prospectivos , Recto/patología , Neoplasias del Cuello Uterino/patología
5.
J Gynecol Obstet Biol Reprod (Paris) ; 39(7): 588-91, 2010 Nov.
Artículo en Francés | MEDLINE | ID: mdl-20627614

RESUMEN

We describe an acute onset of diabetes mellitus during third trimester of pregnancy revealed by ketoacidosis, complicated by fetal death, which could evoke fulminant type 1 diabetes, a novel subtype of type 1 diabetes first described in Japan and rarely described in Caucasian people. Diagnosis of diabetic ketoacidosis could be made on simple signs as abdominal pain, vomiting or ketone bodies on urinary multistix. Capillary glycaemic control is necessary to distinguish fast from ketoacidosis. The treatment of this severe imbalance must be initiated in emergency.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Cetoacidosis Diabética/complicaciones , Muerte Fetal , Embarazo en Diabéticas , Dolor Abdominal , Enfermedad Aguda , Adulto , Glucemia/análisis , Deshidratación/complicaciones , Deshidratación/terapia , Diabetes Mellitus Tipo 1/terapia , Cetoacidosis Diabética/diagnóstico , Cetoacidosis Diabética/terapia , Femenino , Humanos , Insulina/administración & dosificación , Insulina Regular Porcina , Cuerpos Cetónicos , Embarazo , Tercer Trimestre del Embarazo , Embarazo en Diabéticas/terapia , Pielonefritis/complicaciones , Pielonefritis/tratamiento farmacológico , Vómitos
6.
J Gynecol Obstet Biol Reprod (Paris) ; 39(5): 379-86, 2010 Sep.
Artículo en Francés | MEDLINE | ID: mdl-20576363

RESUMEN

OBJECTIVE: Improvement in prenatal diagnosis of Down syndrome imposes to sonographers to realize good quality nuchal translucency measurements, which can be used for assessment of combined risk. The aim of our study was to evaluate a training program of 109 sonographers for measuring nuchal translucency and scoring their own image. STUDY DESIGN: After a proximity training program, trainees submitted 20 images scored by themselves with Herman image-scoring method. All images were reviewed by two experts. RESULTS: One hundred and nine sonographers have accomplished the training program (87.3%), collecting 2162 images. After reviewing, the mean score was 6.8+/-1.8. The rate of inacceptable scan (score< or =3) was in 6.0%. On the other hand, 48.1% of scans were excellent (score> or =8). Only 6.5% of scores were discordant for at least three points between self-scoring and reviewing. After the fourth scan, there was no significant scoring difference between self-scoring and reviewing. Finally, 84% of trainees were very satisfied of this program. CONCLUSION: As part of HAS evaluation of practitioners practices, it is possible to realize proximity training program for measuring nuchal translucency. Learning curve seems to be fast. Good handling of Herman scoring method by sonographers allows their accreditation after this kind of training program.


Asunto(s)
Técnicos Medios en Salud/educación , Síndrome de Down/diagnóstico , Medida de Translucencia Nucal , Femenino , Humanos , Curva de Aprendizaje , Medida de Translucencia Nucal/métodos , Embarazo , Programas de Autoevaluación
9.
J Nanosci Nanotechnol ; 8(11): 6129-40, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19198355

RESUMEN

The boron nitride nanotubes (BNNTs) synthesis, using CO2-laser vaporization of a BN target under nitrogen gas, is investigated by UV-laser induced fluorescence (LIF) of the vapor phase and UV-Rayleigh scattering (RS) of the gas-suspended nanoparticles. The LIF signal from B atoms is mainly detected in the 1.5 mm-thick region above the BN target. It originates from a boron-rich vapor region confined near the hot boron droplet formed at the target surface. Then, recombination between hot boron and N2 gas occurs through a fast condensation process as revealed by both the depletion of B atoms from the vapor phase and the RS signal arising from the grown BN nanoparticles. Fluorescence spectra exhibit a strong peak at 250 nm due to boron fluorescence and mainly to nanoparticles Rayleigh scattering. A narrow peak is observed at 210 nm and a broader peak at 189 nm. These bands are tentatively assigned to fluorescence or photoluminescence (PL) from gaseous or solid BN species respectively since both gas and solid phases coexist in the plume due to the rapid cooling process. Two very weak bands occur at 308 nm and 350 nm. They are related to PL of defects bands from BN nanostructures on the basis of ex situ PL spectra of h-BN crystallites and multi-wall BNNTs. Detection of oxygen impurities is shown feasible through LIF from BO radical which is detected just above the BN target evaporated under vacuum pressure (approximately 1 mbar). An optical diagnostic strategy is demonstrated from these first in situ observations during BNNTs synthesis.


Asunto(s)
Compuestos de Boro/química , Cristalización/métodos , Rayos Láser , Mediciones Luminiscentes/métodos , Ensayo de Materiales/métodos , Nanotecnología/métodos , Nanotubos/química , Nanotubos/ultraestructura , Sustancias Macromoleculares/química , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
10.
J Nanosci Nanotechnol ; 7(10): 3528-32, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18330169

RESUMEN

Continuous laser vaporization of a BN target under N2 atmosphere is up to now the unique route to single-walled boron nitride nanotubes (BN-SWNTs). Although grams of product can be obtained by this technique, the raw material contains in addition to the BN-SWNTs, different by-products made of boron and nitrogen. Since these materials are undesirable for the studying of the intrinsic properties of the nanotubes, we have undertaken a purification process using chemical and physical methods to separate the different components. We show here that most impurities can be removed by successive cycles of washing, sonication, and centrifugation. Furthermore, the two different types of boron nitride nanostructures i.e., BN-SWNTs and BN-cages can be isolated. Efficiency of the separation was monitored by transmission electron microscopy (TEM) at the different steps of the process. Finally, we envisage the further purification of the nanotubes-enriched fraction by functionalizing the nanotubes in a non covalent manner by specific polymers as for carbon nanotubes and BN multi-walled nanotubes.


Asunto(s)
Compuestos de Boro/química , Compuestos de Boro/aislamiento & purificación , Cristalización/métodos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/métodos , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
11.
Gynecol Obstet Fertil ; 34(9): 701-5, 2006 Sep.
Artículo en Francés | MEDLINE | ID: mdl-16919493

RESUMEN

OBJECTIVE: To study the feasibility of a screening for bacterial vaginosis by a self-collected vaginal swab during pregnancy. To measure bacterial vaginosis prevalence in a non-representative sample of women. PATIENTS AND METHODS: A self-collected swab was suggested to 398 women who consulted between 15 and 33 weeks of gestation in three different centres. Gram stain evaluation using Nugent criteria was used for the diagnosis of bacterial vaginosis. RESULTS: Three hundred and forty-one women agreed to take part in the study (86%). The quality of the swabs was satisfactory in 93% of the cases. Concerning the 15 non-interpretable slides, the cellular and bacterial density was too poor, owing to a poor quality or a low vaginal flora. Thirty-one women (9%) had a bacterial vaginosis--Nugent score included between 7 and 10--and this frequency did not vary according to the centre. Thirty-five women (10%) had an intermediate flora--score between 4 and 6--and this result varied from 2 to 12% depending on the centre, but the difference was not significant. DISCUSSION AND CONCLUSION: Self-collected swabs to detect bacterial vaginosis are well accepted by most of pregnant women, and the quality of the swabs seems to be satisfactory. In case vaginal flora is intermediate--between 4 and 6--the interpretation of the slides could be difficult.


Asunto(s)
Complicaciones Infecciosas del Embarazo/microbiología , Manejo de Especímenes/métodos , Vagina/microbiología , Vaginosis Bacteriana/diagnóstico , Femenino , Edad Gestacional , Humanos , Proyectos Piloto , Embarazo , Autocuidado , Vaginosis Bacteriana/epidemiología
12.
J Environ Qual ; 30(6): 2113-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11790021

RESUMEN

Because soil surface structure has a considerable influence on infiltration rate, the sealing process is postulated to have a significant effect on herbicide loss through runoff. We evaluated the effect of degraded soil surface structures on herbicide loss in runoff, and used the experimental data to test the uniform mixing zone concept and two-site sorption kinetics for modeling herbicide transfer to runoff. The experiments were done with simulated rainfall on 10-m2 plots in the field and 0.25-m2 plots in the laboratory after a surface application of 1.5 kg ha(-1) of isoproturon [3-(4-isopropylphenyl)-1,1-dimethylurea] and 0.187 kg ha(-1) of diflufenican [2',4'-difluoro-2-(alpha,alpha,alpha-trifluoro-m-tolyloxy) nicotinanilide]. Isoproturon (IPU) and diflufenican (DFF) concentrations were very high in the first runoff (up to 60 mg L(-1) for IPU and 2 mg L(-1) for DFF) when simulated rainfall was applied 24 h after the treatment. The concentrations decreased very rapidly with total rainfall depth. Degradation of the structural state of the soil surface increased the ratio of pesticide loss to application rate from 0.3 to 10% for IPU and from 0.7 to 7.8% for DFF for a runoff depth of less than 1 mm. The structural state of the soil surface influences the rapidity at which runoff begins after the onset of rain, and the runoff coefficient at steady state. Furthermore, the development of a surface seal seems to limit the depth of soil-runoff interaction and thus influences the dynamics of herbicide mobilization. Concentrations of IPU in the runoff were satisfactorily described with a model incorporating a uniform mixing zone and two-site sorption-desorption.


Asunto(s)
Herbicidas/análisis , Compuestos de Metilurea/análisis , Modelos Teóricos , Niacinamida/análogos & derivados , Niacinamida/análisis , Compuestos de Fenilurea , Lluvia , Contaminantes del Suelo/análisis , Suelo , Predicción , Sedimentos Geológicos/química , Movimientos del Agua
13.
Chemosphere ; 41(5): 645-51, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10834363

RESUMEN

The biodegradability of polymer materials as evaluated by the modified Sturm test is labor-intensive, cumbersome and costly and also tends to cumulate errors. An automated system for the measurement of carbon dioxide would overcome many of these disadvantages. We describe here a method in which CO2 was determined by IR spectroscopy. We compared the results with those from trapping CO2 in a solution of barium hydroxide (Ba(OH)2) followed by manual titration. The automated system was more reproducible, less costly and more compact. The automated system could also be employed to measure the biodegradability of other substances such as oils and detergents.


Asunto(s)
Polímeros/metabolismo , Espectrofotometría Infrarroja/métodos , Automatización , Biodegradación Ambiental , Dióxido de Carbono/análisis , Polímeros/química , Sensibilidad y Especificidad
14.
Mol Cell Endocrinol ; 95(1-2): 67-74, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8243809

RESUMEN

The effect of thyrotropin-releasing hormone (TRH) and gonadotropin-releasing hormone-associated peptide (GAP) was studied on both secretion and intracellular free Ca2+ concentrations ([Ca2+]i) in human pituitary cells cultured from prolactin (PRL)-secreting tumors. Secretion was measured during a 30-min incubation period and we used a microspectrofluorimetric method in individual cells and indo-1 as the fluorescent probe. TRH (10(-8) M) significantly increased PRL release in five out of the six cell populations. In these five cases, more than 68% of individual cells responded to TRH by an increase in [Ca2+]i. No significant increase in PRL secretion was found in another culture in which TRH increased [Ca2+]i in only 37% of the cells. The effect of GAP (10(-7) M) was studied in five cell populations. In three of them, a decrease of 20% to 51% of the PRL basal secretory rate was observed under GAP. GAP inhibited [Ca2+]i in respectively 59%, 46% and 94% of the cells from these cultures. The inhibitory effect of GAP was blocked by a pertussis toxin (PT) pretreatment which demonstrates the involvement of a PT-sensitive G-protein in GAP action. In two other cultures, GAP did not significantly alter PRL secretion or individual cell [Ca2+]i. These observations suggest that GAP might play a role in the control of PRL secretion in the human.


Asunto(s)
Calcio/metabolismo , Hormona Liberadora de Gonadotropina/farmacología , Adenohipófisis/efectos de los fármacos , Neoplasias Hipofisarias/metabolismo , Prolactina/metabolismo , Prolactinoma/metabolismo , Precursores de Proteínas/farmacología , Hormona Liberadora de Tirotropina/farmacología , Adenoma/metabolismo , Adenoma/patología , Adolescente , Adulto , Transporte Biológico/efectos de los fármacos , Femenino , Proteínas de Unión al GTP/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/metabolismo , Toxina del Pertussis , Adenohipófisis/metabolismo , Neoplasias Hipofisarias/patología , Prolactinoma/patología , Sistemas de Mensajero Secundario , Tasa de Secreción/efectos de los fármacos , Células Tumorales Cultivadas/efectos de los fármacos , Factores de Virulencia de Bordetella/farmacología
15.
Endocrinology ; 131(3): 1436-44, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1505473

RESUMEN

Human GH-secreting tumors are heterogenous regarding their basal secretory activity and response to GH-releasing factor (GRF). We have investigated whether such different secretory properties could be accounted for by alterations of intracellular mechanisms occurring at the calcium level. Basal free intracellular calcium concentrations ([Ca2+]i) and Ca2+ responses to GRF were studied in single cells cultured from fragments of five GH-secreting pituitary adenomas. We used the microspectrofluorimetric method and indo-1 as the fluorescent probe. The cell populations cultured from the tumors of patients A and C showed increased hormone secretion in response to GRF in vitro, whereas cultures from patients B, D, and E were unresponsive to the peptide. Basal [Ca2+]i measured in the five cell populations ranged from 82 +/- 18 to 118 +/- 27 nM. A 10-sec application of 10 nM GRF induced an increase in [Ca2+]i in 60% and 54% of A and C cells, respectively. In the nonresponsive cell populations, the number of calcium responses to GRF was lower, 26% (B cells), 5% (D cells), and 10% (E cells). Two principal responses types were observed: 1) an initial increase in [Ca2+]i, followed by a sustained plateau phase lasting for more than 200 sec; and 2) a monophasic peak of increased [Ca2+]i lasting approximately 1 min before returning to baseline levels. GRF responses were totally suppressed in the absence of Ca2+ ions in the external medium. Sixteen to 30% of the cells cultured from four of the five tumors showed spontaneous fluctuations of [Ca2+]i. These spontaneous Ca2+ transients were suppressed in Ca(2+)-free medium. The number of cells exhibiting such Ca2+ transients decreased with time in culture. Basal hormone secretion was higher in cultures from patient D, in which no spontaneous Ca2+ transients were observed in any of the 72 studied cells, and in cultures from patients E, in which only 16% of cells were spontaneously active. We conclude that 1) in human responsive somatotrophs, the involvement of Ca2+ in GRF stimulus-secretion coupling mechanisms is apparently similar to that described in somatotrophs of other species; 2) the lack of a secretory response to GRF observed in some tumors may result from impairment of Ca2+ responsiveness in either cell recruitment or response amplitude and/or duration; and 3) spontaneous rhythmic Ca2+ activity is apparently dissociated from basal hormone secretion in some of these tumor cells.


Asunto(s)
Adenoma/metabolismo , Calcio/metabolismo , Hormona del Crecimiento/metabolismo , Neoplasias Hipofisarias/metabolismo , Adenoma/cirugía , Adulto , Supervivencia Celular , Citosol/efectos de los fármacos , Citosol/metabolismo , Femenino , Hormona Liberadora de Hormona del Crecimiento/farmacología , Homeostasis , Humanos , Cinética , Masculino , Persona de Mediana Edad , Neoplasias Hipofisarias/cirugía , Células Tumorales Cultivadas
16.
Endocrinology ; 129(4): 2126-30, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1915092

RESUMEN

The GH3 pituitary cell line has been extensively used to study various aspects of the stimulus secretion coupling process. It is known that GH3 cells release PRL and GH in the basal state and in response to various secretagogues. However, this cell line was considered unsuitable as a model for studying the effects of GHRF since the neuropeptide did not affect GH secretion or gene expression. This suggested that the GH3 cells may lack GHRF receptors. The present study investigates the effect of GHRF on free intracellular Ca2+ concentrations in GH3 cells. Cytosolic free calcium concentrations ([Ca2+]i) were monitored in individual cells by microspectrofluorimetry using the fluorescent dye indo 1. When the cells were challenged with a brief application of GHRF (100 nM; 15 sec), 36 out of 59 of these cells responded within a few seconds by a marked increase in [Ca2+]i. GHRF enhanced the frequency of [Ca2+]i oscillations in spontaneously active cells or triggered [Ca2+]i oscillations in inactive cells. The response to GHRF was totally blocked by external Ca2+ free solutions and Ca2+ channel blockers. Combined electrophysiological and fluorescent experiments were carried out in 16 cells. Eleven responded to GHRF. In all cases, the Ca2+ transients triggered by GHRF were associated with action potentials. The Ca2+ responses observed in our experiments clearly show that GH3 cells possess membrane receptors to GHRF. Thus, it is likely that the lack of secretory response observed in GH3 cells does not result from the absence of binding sites to the peptide. It is more likely to be related to alterations of transduction mechanisms resulting in uncoupling between stimulation and secretion.


Asunto(s)
Calcio/metabolismo , Hormona Liberadora de Hormona del Crecimiento/farmacología , Hipófisis/metabolismo , Línea Celular , Electrofisiología , Concentración Osmolar , Hipófisis/citología , Hipófisis/fisiología , Espectrometría de Fluorescencia
17.
C R Seances Soc Biol Fil ; 185(4): 218-23, 1991.
Artículo en Francés | MEDLINE | ID: mdl-1836417

RESUMEN

The effect of GH-RH in the intra-cytosolic free Ca2+ concentration was studied in GH3 cells. To this end, we have used microspectrofluorimetry performed on single cells. We show that 60% of cells respond to a brief application of 100 nM GH-RH by an increase of their [Ca2+]i (mean increase 100% over basal values). This response which is blocked by calcium channel inhibitors results from an increased influx of Ca2+ ions from the external medium.


Asunto(s)
Calcio/metabolismo , Hormona Liberadora de Hormona del Crecimiento/farmacología , Neoplasias Hipofisarias/patología , Animales , Línea Celular Transformada/efectos de los fármacos , Línea Celular Transformada/metabolismo , Citosol/metabolismo , Ratas
18.
C R Seances Soc Biol Fil ; 185(4): 224-30, 1991.
Artículo en Francés | MEDLINE | ID: mdl-1836418

RESUMEN

We have investigated the electrical response of patched GH3 cells to Growth-Hormone Releasing-Hormone (GH-RH). GH-RH (100 nM) enhanced firing frequency of action potentials. This is accompanied by membrane depolarization (5-10 mV) and conductance increase. Voltage clamp studies reveal that GH-RH potentiates calcium inward currents and a calcium-dependent chloride current; transient outward current is diminished. These changes in membrane conductance account for the cytosolic free calcium rise shown by Indo-1 fluorescence measurements.


Asunto(s)
Hormona Liberadora de Hormona del Crecimiento/fisiología , Neoplasias Hipofisarias/patología , Potenciales de Acción/efectos de los fármacos , Animales , Calcio/fisiología , Línea Celular Transformada/fisiología , Electrofisiología , Potenciales de la Membrana/fisiología , Ratas , Células Tumorales Cultivadas
19.
Paris; C. Reinwald; 1888. 472 p.
Monografía en Francés | Coleciona SUS, IMNS | ID: biblio-929539
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