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1.
Exp Clin Endocrinol Diabetes ; 123(5): 267-71, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25853704

RESUMEN

BACKGROUND: Type 2 Diabetes Mellitus is a leading cause of end stage renal disease in the worldwide. Inflammation is regarded as one of the main reasons for the progression of diabetes complications. We aimed to evaluate the association of neutrophil to lymphocyte ratio (NLR) as indicator of systemic inflammation with diabetic retinopathy and nephropathy. PATIENTS AND METHODS: This is a cross-sectional study of 114 prevalent type 2 diabetic subjects. All of the patients underwent detailed examination for the presence of diabetic retinopathy and nephropathy. Diabetic retinopathy was approved and classified according to findings based on flouresceint fundal angiography results. Estimated glomerular filtration rate (eGFR) and microalbumin to creatinine ratio were calculated to establish the diabetic nephropathy. NLR was calculated as ratio of absolute neutrophil count to absolute lymphocyte count. RESULTS: Retinopathy was present in 55 (48.2%) out of 114 patients, whereas nephropathy was present in 62 patients (54.3%). NLR was significantly higher in patients with nephropathy than in patients without nephropathy. NLR was also positively correlated with CRP (p=0.017, r=0.224) and microalbuminuria (p=0.016, r=0.257) whereas negatively correlated with eGFR (p<0.001, r=-0.337) values in the whole cohort. NLR was independent predictors for diabetic nephropathy, whereas it did not appear as an independent associate of diabetic retinopathy. CONCLUSION: NLR and diabetic nephropathy have an independent association between them whereas there was no independent association between NLR with retinopathy in type 2 diabetic patients.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Angiopatías Diabéticas/inmunología , Nefropatías Diabéticas/inmunología , Linfocitos/inmunología , Neutrófilos/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Estudios de Cohortes , Estudios Transversales , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/epidemiología , Angiopatías Diabéticas/fisiopatología , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/epidemiología , Nefropatías Diabéticas/fisiopatología , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/epidemiología , Retinopatía Diabética/inmunología , Retinopatía Diabética/fisiopatología , Femenino , Angiografía con Fluoresceína , Tasa de Filtración Glomerular , Hospitales Comunitarios , Humanos , Inflamación/sangre , Inflamación/epidemiología , Inflamación/fisiopatología , Masculino , Persona de Mediana Edad , Servicio Ambulatorio en Hospital , Índice de Severidad de la Enfermedad , Turquía/epidemiología
2.
Med Decis Making ; 35(6): 714-25, 2015 08.
Artículo en Inglés | MEDLINE | ID: mdl-24842951

RESUMEN

BACKGROUND: Multiple embryo transfers in in vitro fertilization (IVF) treatment increase the number of successful pregnancies while elevating the risk of multiple gestations. IVF-associated multiple pregnancies exhibit significant financial, social, and medical implications. Clinicians need to decide the number of embryos to be transferred considering the tradeoff between successful outcomes and multiple pregnancies. OBJECTIVE: To predict implantation outcome of individual embryos in an IVF cycle with the aim of providing decision support on the number of embryos transferred. DESIGN: Retrospective cohort study. DATA SOURCE: Electronic health records of one of the largest IVF clinics in Turkey. The study data set included 2453 embryos transferred at day 2 or day 3 after intracytoplasmic sperm injection (ICSI). Each embryo was represented with 18 clinical features and a class label, +1 or -1, indicating positive and negative implantation outcomes, respectively. METHODS: For each classifier tested, a model was developed using two-thirds of the data set, and prediction performance was evaluated on the remaining one-third of the samples using receiver operating characteristic (ROC) analysis. The training-testing procedure was repeated 10 times on randomly split (two-thirds to one-third) data. The relative predictive values of clinical input characteristics were assessed using information gain feature weighting and forward feature selection methods. RESULTS: The naïve Bayes model provided 80.4% accuracy, 63.7% sensitivity, and 17.6% false alarm rate in embryo-based implantation prediction. Multiple embryo implantations were predicted at a 63.8% sensitivity level. Predictions using the proposed model resulted in higher accuracy compared with expert judgment alone (on average, 75.7% and 60.1%, respectively). CONCLUSIONS: A machine learning-based decision support system would be useful in improving the success rates of IVF treatment.


Asunto(s)
Algoritmos , Técnicas de Apoyo para la Decisión , Implantación del Embrión , Transferencia de Embrión/estadística & datos numéricos , Fertilización In Vitro/estadística & datos numéricos , Aprendizaje Automático , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Adulto , Estudios de Cohortes , Femenino , Humanos , Embarazo , Embarazo Múltiple/estadística & datos numéricos , Estudios Retrospectivos , Inyecciones de Esperma Intracitoplasmáticas , Turquía
3.
Hum Reprod ; 29(12): 2650-60, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25344070

RESUMEN

STUDY QUESTION: Can the approach to, and terminology for, time-lapse monitoring of preimplantation embryo development be uniformly defined in order to improve the utilization and impact of this novel technology? SUMMARY ANSWER: The adoption of the proposed guidelines for defining annotation practice and universal nomenclature would help unify time-lapse monitoring practice, allow validation of published embryo selection algorithms and facilitate progress in this field. WHAT IS KNOWN ALREADY: An increasing quantity of publications and communications relating to time-lapse imaging of in vitro embryo development have demonstrated the added clinical value of morphokinetic data for embryo selection. Several articles have identified similar embryo selection or de-selection variables but have termed them differently. An evidence-based consensus document exists for static embryo grading and selection but, to date, no such reference document is available for time-lapse methodology or dynamic embryo grading and selection. STUDY DESIGN, SIZE AND DURATION: A series of meetings were held between September 2011 and May 2014 involving time-lapse users from seven different European centres. The group reached consensus on commonly identified and novel time-lapse variables. PARTICIPANTS/MATERIALS, SETTING, METHODS: Definitions, calculated variables and additional annotations for the dynamic monitoring of human preimplantation development were all documented. MAIN RESULTS AND THE ROLE OF CHANCE: Guidelines are proposed for a standard methodology and terminology for the of use time-lapse monitoring of preimplantation embryo development. LIMITATIONS, REASONS FOR CAUTION: The time-lapse variables considered by this group may not be exhaustive. This is a relatively new clinical technology and it is likely that new variables will be introduced in time, requiring revised guidelines. A different group of users from those participating in this process may have yielded subtly different terms or definitions for some of the morphokinetic variables discussed. Due to the technical processes involved in time-lapse monitoring, and acquisition of images at varied intervals through limited focal planes, this technology does not currently allow continuous monitoring such that the entire process of preimplantation embryo development may be visualized. WIDER IMPLICATIONS: This is the first time that a group of experienced time-lapse users has systematically evaluated current evidence and theoretical aspects of morphokinetic monitoring to propose guidelines for a standard methodology and terminology of its use and study, and its clinical application in IVF. The adoption of a more uniform approach to the terminology and definitions of morphokinetic variables within this developing field of clinical embryology would allow practitioners to benefit from improved interpretation of data and the sharing of best practice and experience, which could impact positively and more swiftly on patient treatment outcome. STUDY FUNDING/COMPETING INTERESTS: There was no specific funding for the preparation of these proposed guidelines. Meetings were held opportunistically during scientific conferences and using online communication tools. H.N.C. is a scientific consultant for ESCO, supplier of Miri TL. I.E.A. is a minor shareholder in Unisense Fertilitech, supplier of the EmbryoScope. Full disclosures of all participants are presented herein. The remaining authors have no conflict of interest.


Asunto(s)
Blastocisto , Desarrollo Embrionario , Terminología como Asunto , Ciclo Celular , Técnicas de Cultivo de Embriones , Embrión de Mamíferos/citología , Embrión de Mamíferos/ultraestructura , Humanos , Imagen de Lapso de Tiempo
6.
Fertil Steril ; 95(5): 1860-2, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21075368

RESUMEN

The distribution of six physicians' pregnancy rates with cycle and patient demographics was investigated for 2,212 transfer cycles. The results indicate that when the patient and cycle characteristics are compromised, the level of physician experience may determine the outcome of embryo transfers.


Asunto(s)
Transferencia de Embrión/estadística & datos numéricos , Médicos , Resultado del Embarazo/epidemiología , Competencia Profesional , Adulto , Transferencia de Embrión/métodos , Femenino , Humanos , Infertilidad/terapia , Rol del Médico , Embarazo , Índice de Embarazo , Competencia Profesional/estadística & datos numéricos , Estudios Retrospectivos , Resultado del Tratamiento
7.
Fertil Steril ; 94(7): 2769.e5-7, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20542502

RESUMEN

OBJECTIVE: To assess cycle outcome after oocyte refrigeration. DESIGN: Case report. SETTING: Private IVF center. PATIENT(S): One couple in a donor oocyte program. INTERVENTION(S): Intracytoplasmic sperm injection and blastocyst culture after refrigeration of oocytes for 12 hours. MAIN OUTCOME MEASURE(S): Birth. RESULT(S): Fourteen two-pronuclei zygotes from 17 metaphase II refrigerated oocytes resulted in transfer of two blastocysts at day 5 and cryopreservation of six excess embryos at day 6. The patient delivered one healthy male baby after 38 weeks' gestation. CONCLUSION(S): The successful outcome of oocyte refrigeration indicates that this protocol could be useful in circumstances in which a delay in obtaining spermatozoa arises.


Asunto(s)
Oocitos , Parto , Refrigeración , Conservación de Tejido/métodos , Femenino , Fertilización In Vitro/métodos , Humanos , Recién Nacido , Infertilidad/terapia , Masculino , Persona de Mediana Edad , Parto/fisiología , Embarazo , Refrigeración/métodos , Factores de Tiempo
8.
Artículo en Inglés | MEDLINE | ID: mdl-19964898

RESUMEN

Implantation prediction of in-vitro fertilization (IVF) embryos is critical for the success of the treatment. In this study, Support Vector Machine (SVM) method has been used on an original IVF dataset for classification of embryos according to implantation potentials. The dataset we analyzed includes both categorical and continuous feature values. Transformation of categorical variables into numeric attributes is an important pre-processing stage for SVM affecting the performance of the classification. We have proposed a frequency based encoding technique for transformation of categorical variables. Experimental results revealed that, the proposed technique significantly improved the performance of IVF implantation prediction in terms of Area Under ROC curve (0.712+/-0.032) compared to common binary encoding and expert judgement based transformation methods (0.676+/-0.033 and 0.696 +/- 0.024, respectively).


Asunto(s)
Algoritmos , Inteligencia Artificial , Sistemas de Apoyo a Decisiones Clínicas , Técnicas de Apoyo para la Decisión , Fertilización In Vitro , Evaluación de Resultado en la Atención de Salud/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Humanos , Pronóstico
9.
Fertil Steril ; 91(4 Suppl): 1459-61, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18722608

RESUMEN

A prospective randomized study was carried on sibling oocytes in which human gametes and embryos were cultured at physiologic (6% CO(2) + 5% O(2) + 89% N(2)) condition from insemination to day 6 or at atmospheric (6% CO(2) in air) condition until day 3 and at physiologic environment afterward. The results showed that physiologic oxygen concentration throughout culture period improved total blastocyst yield and day 5 embryo quality.


Asunto(s)
Blastocisto/efectos de los fármacos , Técnicas de Cultivo de Embriones/métodos , Transferencia de Embrión/métodos , Oocitos/efectos de los fármacos , Oxígeno/farmacología , Hermanos , Blastocisto/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Fertilización In Vitro/métodos , Humanos , Masculino , Recuperación del Oocito , Oocitos/fisiología , Estudios Prospectivos , Inyecciones de Esperma Intracitoplasmáticas
10.
Reprod Biomed Online ; 16(6): 875-80, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18549699

RESUMEN

Gamete characteristics are likely to contribute to embryo development. In this preliminary study, early parameters were assessed in embryos generated following microinjection of hyaluronan-bound and unbound spermatozoa into 176 sibling oocytes, which had themselves been assessed using a polarizing light microscope imaging system. The fertilization and early cleavage rates, and day 3 embryo quality did not differ when oocytes displaying similar characteristics were inseminated with either bound or unbound sperm. Regardless of the binding characteristics of the sperm, early embryos displaying good and poor quality derived from oocytes displaying visible spindles and similar characteristics. These results indicate that early embryo developmental characteristics were independent from the hyaluronic acid binding capacity of the sperm when oocytes displayed a visible spindle.


Asunto(s)
Desarrollo Embrionario , Fertilización In Vitro , Oocitos/citología , Espermatozoides/citología , Adulto , Femenino , Humanos , Ácido Hialurónico/metabolismo , Masculino , Microscopía de Polarización , Proyectos Piloto , Embarazo , Espermatozoides/metabolismo
11.
Reprod Biomed Online ; 15(2): 156-60, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17697490

RESUMEN

The aim of this study was to evaluate the impact of gonadotrophin therapy in combination with intracytoplasmic sperm injection (ICSI) in men with hypogonadotrophic hypogonadism (HH). Twenty-five azoospermic men were diagnosed with HH due to low FSH, LH and total testosterone concentrations. These patients were treated with human chorionic gonadotrophin for 1 month plus recombinant FSH the following month. Total testosterone concentrations were measured in the first and third months. Semen analyses were performed monthly after the third month of treatment. ICSI was performed when sperm production commenced. Total testosterone concentration and testicular volume were significantly increased after gonadotrophin therapy (P < 0.001). On average, spermatozoa were detected in the ejaculate after 10 months. Spontaneous pregnancies were achieved in four couples. Twenty-two ICSI cycles were performed in 18 couples using ejaculated or testicular spermatozoa, and 12 pregnancies (54.5% per cycle) were achieved. These results showed that HH could be treated successfully with hormonal therapy combined with ICSI using ejaculated spermatozoa. The use of ICSI made it possible to achieve pregnancy when spermatozoa appeared in the ejaculate, and shortened the duration of gonadotrophin therapy.


Asunto(s)
Azoospermia/tratamiento farmacológico , Gonadotropina Coriónica/uso terapéutico , Hormona Folículo Estimulante Humana/uso terapéutico , Hipogonadismo/tratamiento farmacológico , Inyecciones de Esperma Intracitoplasmáticas , Adulto , Azoospermia/etiología , Femenino , Humanos , Hipogonadismo/complicaciones , Masculino , Embarazo , Índice de Embarazo
12.
Fertil Steril ; 87(5): 1218-21, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17241626

RESUMEN

The objective of investigating the impact of the time that embryos remain in the catheter on the outcome of cycles was assessed by measuring the period between loading the catheter and discharging the embryos in 300 transfer cycles. The pregnancy and implantation rates were similar in cycles with good embryo quality regardless of transfer duration.


Asunto(s)
Transferencia de Embrión/normas , Resultado del Embarazo/epidemiología , Adolescente , Adulto , Femenino , Humanos , Embarazo , Control de Calidad , Factores de Tiempo
13.
Reprod Biomed Online ; 13(4): 516-22, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17007672

RESUMEN

The purpose of this study was to contribute to the development of strategies to obtain acceptable outcomes in assisted reproduction treatments in women over 40 years of age. A retrospective study was carried out on the database of the German Hospital in Istanbul using data from the years 1997 to 2004. A total of 1114 embryo transfer cycles were assessed. The pregnancy, implantation and delivery rates of the assessed population were 18.2, 8.3 and 10.9% respectively. The results showed that the demographics and outcome of cycles of women at 40 years differed significantly from those over 40. Cycles in which six or more oocytes were retrieved displayed better characteristics and outcome than those with five or fewer. The clinical pregnancy and delivery rates after transfer of three embryos were similar to four or more. Therefore, women over 40 years with a good ovarian response and at least three embryos available for transfer have an acceptable pregnancy and delivery rate with a low multiple pregnancy risk.


Asunto(s)
Edad Materna , Resultado del Embarazo , Inyecciones de Esperma Intracitoplasmáticas , Adulto , Recuento de Células , Implantación del Embrión , Transferencia de Embrión , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Persona de Mediana Edad , Oocitos/fisiología , Embarazo , Índice de Embarazo , Estudios Retrospectivos
14.
Fertil Steril ; 86(1): 81-5, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16716322

RESUMEN

OBJECTIVE: To compare the outcome of day 2 and day 3 embryo transfers in women demonstrating poor ovarian response. DESIGN: Prospective randomized clinical trial. SETTING: Private assisted reproductive technology center. PATIENT(S): Two hundred eighty-one women demonstrating poor ovarian response to controlled ovarian hyperstimulation. INTERVENTION(S): Women who were poor responders were randomly allocated to day 2 or day 3 embryo transfer following oocyte retrieval. MAIN OUTCOME MEASURE(S): Implantation rates and pregnancy rates per oocyte retrieval and embryo transfer. RESULT(S): The clinical pregnancy rates per oocyte retrieval (37.2% vs. 21.4%, respectively; P<.05) and per embryo transfer (38.9% vs. 24.1%, respectively; P<.05) were significantly higher in the day 2 embryo transfer group compared with day 3. On the other hand, implantation rates were not different between groups (23.9% vs. 17.2%, respectively; P=.08). CONCLUSION(S): Our results demonstrated that transfering embryos on day 2 could provide an alternative to the management of poor responder patients.


Asunto(s)
Transferencia de Embrión/estadística & datos numéricos , Infertilidad Femenina/epidemiología , Infertilidad Femenina/terapia , Inducción de la Ovulación/estadística & datos numéricos , Índice de Embarazo , Adulto , Femenino , Humanos , Embarazo , Estudios Prospectivos , Insuficiencia del Tratamiento , Resultado del Tratamiento , Turquía/epidemiología
15.
Reprod Biomed Online ; 11(4): 438-43, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16274603

RESUMEN

The hypothesis that ICSI outcome can be improved by culturing human embryos in an atmosphere of controlled O(2) concentration (5%) compared with 20% was tested in a prospective randomized study of 712 transfer cycles. The cycle characteristics and the embryology parameters were similar between groups. The embryo qualities were similar with day 2 transfers; however, they were better with day 3 transfers incubated in 5% O(2) than in 20% O(2). The clinical outcome parameters did not differ between groups according to the O(2) concentration. The results indicated that culture of embryos under atmospheric conditions of O(2) for the first 2 or 3 days did not alter the clinical outcome in ICSI cycles.


Asunto(s)
Transferencia de Embrión , Embrión de Mamíferos/metabolismo , Oxígeno/metabolismo , Inyecciones de Esperma Intracitoplasmáticas/métodos , Blastocisto , Células Cultivadas , Implantación del Embrión , Embrión de Mamíferos/citología , Femenino , Fertilización In Vitro/métodos , Humanos , Masculino , Oocitos/citología , Oocitos/metabolismo , Embarazo , Índice de Embarazo , Estudios Prospectivos , Factores de Tiempo
16.
Hum Reprod ; 20(9): 2546-9, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15905297

RESUMEN

BACKGROUND: Assisted hatching can improve the implantation rate in cycles with poor outcome. The impact of assisted hatching in embryos from women with endometriosis is not known. Therefore, the hypothesis that the implantation potential of embryos obtained from women with endometriosis can be improved with assisted hatching was tested. METHODS: In a prospective randomized study, transfer embryos obtained from 60 women with endometriosis were hatched using a laser system and compared to embryos obtained from patients with the same diagnosis which were left intact (n = 30). RESULTS: The characteristics of cycles were similar between groups. The pregnancy (40% zona intact, 28.3% assisted hatching), and implantation rates (19.4% zona intact, 17.8% assisted hatching) did not differ in endometriosis cycles regardless of assisted hatching. CONCLUSION: Assisted hatching does not improve outcome in women with endometriosis undergoing assisted reproduction.


Asunto(s)
Implantación del Embrión , Endometriosis/complicaciones , Infertilidad Femenina/terapia , Resultado del Embarazo , Técnicas Reproductivas Asistidas , Adulto , Femenino , Humanos , Infertilidad Femenina/etiología , Embarazo , Estudios Prospectivos , Zona Pelúcida
17.
Reprod Biomed Online ; 8(2): 219-23, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14989803

RESUMEN

The hypothesis that inspection for early cleavage improves pregnancy rate by aiding selection of the best embryos for transfer was tested in this study. Inspection for early cleavage was performed randomly in women undergoing intracytoplasmic sperm injection (ICSI) cycles. No differences were observed between early cleavage-inspected and uninspected embryos. When the hypothesis that transfer of early-cleaved (EC) embryos yields a higher pregnancy rate than transfer of late-cleaved (LC) embryos was tested using early cleavage-inspected cycles, it was found that transfer of EC embryos resulted in a higher implantation rate than transfer of LC embryos. In transfers for which all embryos were EC (100% EC), transfer of fewer embryos yielded a higher implantation rate compared with LC and uninspected cycles. These results indicate that, when inspected, early cleavage increases the implantation rate in ICSI patients.


Asunto(s)
Blastocisto/fisiología , Fase de Segmentación del Huevo/fisiología , Implantación del Embrión/fisiología , Transferencia de Embrión , Adulto , Femenino , Humanos , Inducción de la Ovulación , Embarazo , Técnicas Reproductivas Asistidas , Inyecciones de Esperma Intracitoplasmáticas
18.
Am J Obstet Gynecol ; 182(4): 926-30, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10764475

RESUMEN

OBJECTIVE: Our objective was to study the appearance and distribution of connexins 43 and 26 in various human myometrial cell cultures. STUDY DESIGN: Scrape loading, Western blotting, and immunohistochemical techniques were applied to cultured cells derived from myometrial tissues obtained from nonpregnant and pregnant women (upper and lower uterine segments) and from leiomyomas (tumor and analogous myometrial tissues). RESULTS: Scrape loading revealed the presence of metabolic coupling in all tissues. Indirect immunohistochemical studies showed membrane localization of connexin 43 in all myometrial cultures. Western blots and indirect immunohistochemical studies showed the presence and localization of the connexin 26 protein and associated gap junctions in tissues from myomas and from nonpregnant and pregnant women except for those derived from the upper segment of the pregnant uterus. CONCLUSION: These results show that human myometrial cultures express various gap junction proteins and that there are regional differences in expression of connexins in tissues from pregnant women.


Asunto(s)
Conexina 43/metabolismo , Conexinas/metabolismo , Leiomioma/metabolismo , Miometrio/metabolismo , Embarazo/metabolismo , Neoplasias Uterinas/metabolismo , Western Blotting , Células Cultivadas , Conexina 26 , Electroforesis en Gel Bidimensional , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Uniones Comunicantes/ultraestructura , Humanos , Inmunohistoquímica , Miometrio/citología , Valores de Referencia , Distribución Tisular
19.
Am J Obstet Gynecol ; 178(4): 855-61, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9579456

RESUMEN

OBJECTIVE: The effects of the uterotonic agent oxytocin on intercellular communication between term pregnant human myometrial cells before labor were studied to investigate its contribution to the synchronicity of uterine contractions. STUDY DESIGN: The membrane potential and the input resistance of myometrial cells were measured with intracellular micropipettes, and dye-coupling assays were concomitantly performed while the tissues were perfused with three concentrations of oxytocin (10(-8) mol/L, 10(-7) mol/L, and 10(-6) mol/L). The results were compared with those obtained from tissues perfused with gap junctional uncoupling agent octanol and those with Tyrode's solution (control). RESULTS: Octanol increased input resistance and inhibited dye coupling but did not affect membrane potential compared with controls. Oxytocin depolarized membrane potential at all studied concentrations. The mean input resistance values and detectable dye propagation with oxytocin were similar to controls. CONCLUSION: Oxytocin does not contribute to gap junctional intercellular communication in term pregnant human myometrium before labor but may affect contractions by depolarizing membrane potential.


Asunto(s)
Comunicación Celular/efectos de los fármacos , Trabajo de Parto , Miometrio/citología , Oxitocina/farmacología , Impedancia Eléctrica , Femenino , Fluoresceínas , Colorantes Fluorescentes , Humanos , Potenciales de la Membrana/efectos de los fármacos , Microscopía Fluorescente , Octanoles/farmacología , Embarazo
20.
Biol Reprod ; 55(2): 379-85, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8828843

RESUMEN

The appearance of gap junctions (GJs) between myometrial smooth muscle cells is one of the major events associated with the onset of labor. We have employed dye-coupling and electrical-current injection techniques to study the mechanisms by which steroid hormones regulate GJs in term pregnant myometrium of women before labor. Progesterone (P4) did not alter the input resistance (Ro) of the tissues when added to Tyrode's solution, which was used as control treatment. Octanol, the putative gap junctional uncoupling agent, increased the Ro of the cells compared to the control and P4-treated groups. The membrane potential (Em) did not differ between these groups. However, when P4 was applied after the tissue was perfused with estradiol (E2), the results changed dramatically: the Em hyperpolarized, and the Ro increased. Octanol increased the Ro in E2-treated tissues, but did not affect the Em. Consecutive application of E2, octanol, E2, and P4 resulted in rapid changes in the Ro of the cells. Dye-coupling was mostly detected between cells from controls and E2-treated tissues. These results indicate that P4 exerts its effects in the presence of E2 and that P4 has rapid effects on the intercellular communication between human myometrial cells.


Asunto(s)
Comunicación Celular/efectos de los fármacos , Comunicación Celular/fisiología , Estradiol/farmacología , Trabajo de Parto/fisiología , Miometrio/citología , Progesterona/farmacología , Colorantes , Conductividad Eléctrica , Impedancia Eléctrica , Femenino , Humanos , Potenciales de la Membrana , Miometrio/efectos de los fármacos , Octanoles/farmacología , Embarazo
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