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1.
Vox Sang ; 112(3): 229-239, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28220499

RESUMEN

BACKGROUND AND OBJECTIVES: Traditionally, Denmark has had a high rate of allogeneic red blood cell transfusion caused by a liberal transfusion practice despite the existence of restrictive guidelines. We established a Patient Blood Management programme in a tertiary hospital and report the results of the implementation of evidence-based transfusion practice. MATERIALS AND METHODS: Red blood cell transfusion quality indicators were compared with the evidence-based guideline at hospital and department level. Based on this evaluation, wards were selected for interventions targeting doctors and nurses. The implementation process was monitored by transfusion quality and utilization data over a 3-year period with totally 166 341 admissions in 98 960 mixed, adult medical and surgical patients. RESULTS: At the hospital level, transfusion above the upper guideline limit decreased from 23 to 10% (P < 0·001), and transfusion at or below the restrictive haemoglobin trigger of 7·3 g/dl increased from 7 to 19% (P < 0·001). The percentage of single-unit transfusions increased from 72 to 78% (P < 0·001), and the majority of transfusion rates and volumes decreased significantly. Red cell use decreased with 41% in surgical procedures and 28% in admissions (P < 0·001). CONCLUSION: The intervention was associated with a significant and sustained overall increase in compliance with national guidelines for red blood cell transfusion for non-bleeding patients, and led to significantly fewer patients being exposed to transfusion.


Asunto(s)
Transfusión de Eritrocitos , Adulto , Bases de Datos Factuales , Dinamarca , Práctica Clínica Basada en la Evidencia , Femenino , Estudios de Seguimiento , Hemoglobinas/análisis , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Centros de Atención Terciaria
2.
Opt Express ; 20(14): 15872-81, 2012 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-22772277

RESUMEN

The output of high power fiber amplifiers is typically limited by stimulated Brillouin scattering (SBS). An analysis of SBS with a chirped pump laser indicates that a chirp of 2.5 × 10(15) Hz/s could raise, by an order of magnitude, the SBS threshold of a 20-m fiber. A diode laser with a constant output power and a linear chirp of 5 × 10(15) Hz/s has been previously demonstrated. In a low-power proof-of-concept experiment, the threshold for SBS in a 6-km fiber is increased by a factor of 100 with a chirp of 5 × 10(14) Hz/s. A linear chirp will enable straightforward coherent combination of multiple fiber amplifiers, with electronic compensation of path length differences on the order of 0.2 m.

3.
J Clin Endocrinol Metab ; 97(3): 957-66, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22238403

RESUMEN

CONTEXT: In fertile patients the endometrial Wilms tumor suppressor gene (WT1) is expressed during the window of implantation. Polycystic ovary syndrome (PCOS) patients suffer from hyperandrogenemia and infertility and have elevated endometrial androgen receptor (AR) expression. WT1 is known to be down-regulated by AR. Therefore, the expression of WT1 and its targets may be altered in PCOS endometrium. OBJECTIVE: The objective of the study was to assess the expression and regulation of WT1 and selected downstream targets in secretory endometrium from ovulatory PCOS (ovPCOS) and fertile women. DESIGN AND PATIENTS: Endometrial samples were obtained from 25 ovPCOS and 25 fertile patients. MAIN OUTCOME MEASURE: Endometrial expression of WT1 and selected downstream targets were assessed by immunohistochemistry and RT-PCR. The androgen effect on WT1 expression was determined in vitro by immunoblots and RT-PCR. The expression of WT1 and its targets was quantified in fertile and ovPCOS stromal cells in the presence of androgens by RT-PCR. Caspase-3/7 activity was measured to evaluate sensitivity to drug-induced apoptosis. RESULTS: WT1 expression was down-regulated in secretory-phase ovPCOS endometrium. Stromal expression of Bcl-2 and p27 was higher, and epidermal growth factor receptor was lower in ovPCOS than in fertile patients. Endometrial stromal expression of WT1, Bcl-2, Bcl-2-associated X protein, and ß-catenin was regulated by androgens. Apoptosis levels were reduced in ovPCOS samples and androgen-treated fertile samples. CONCLUSION: WT1 expression is down-regulated in ovPCOS endometrium during the window of implantation. Androgens regulate the expression of WT1 and its targets during endometrial decidualization. The altered balance between WT1 and AR in the endometrium of PCOS patients may jeopardize the success of decidualization and endometrial receptivity.


Asunto(s)
Endometrio/metabolismo , Hiperandrogenismo/metabolismo , Infertilidad Femenina/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Proteínas WT1/metabolismo , Adulto , Caspasa 3/genética , Caspasa 3/metabolismo , Caspasa 7/genética , Caspasa 7/metabolismo , Femenino , Humanos , Hiperandrogenismo/genética , Infertilidad Femenina/genética , Síndrome del Ovario Poliquístico/genética , Proteínas WT1/genética
4.
J Microsc ; 240(2): 111-21, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20946377

RESUMEN

Atomic force microscopy enables the simultaneous acquisition of high-resolution topographical and biophysical data allowing integrated analysis of cell surfaces during development and pathogenesis, and, critically, can link molecular and biophysical events. Here we used atomic force microscopy to analyse endometrial epithelial cells and neuronally differentiated P19 cells. Optimized reproducible sample preparation techniques enabled micro- and nanoscale multi-parameter analysis. Comparative analysis using atomic force microscopy and scanning electron microscopy demonstrated the utility of atomic force microscopy for examining tissue morphology, and its ability to generate data allowing differentiation of cells from different origins to be monitored. At low resolution atomic force microscopy produced topographic data complementary to scanning electron microscopy images, whilst at high resolution atomic force microscopy captured novel cell surface structural detail for both epithelial and neuronal cell types. Analysis of surface roughness provided biophysical data which enabled qualitative and quantitative differences between samples to be measured. This study provides an important optimization of sample preparation enabling more generalized atomic force microscopy utilization for cellular analysis required for advanced cell surface morphological studies.


Asunto(s)
Microscopía de Fuerza Atómica , Fijación del Tejido/métodos , Línea Celular Tumoral , Membrana Celular/ultraestructura , Endometrio/ultraestructura , Células Epiteliales/ultraestructura , Femenino , Humanos , Aumento de la Imagen , Microscopía Electrónica de Rastreo
5.
J Clin Endocrinol Metab ; 95(12): 5320-9, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20826587

RESUMEN

CONTEXT: Endometrium of fertile women expresses progesterone-regulated Mucin 1 (MUC1) that carries selectin ligands recognized by the human blastocyst. Altered MUC1 expression at the time of implantation may contribute to endometrial infertility. OBJECTIVE: The aim was to assess the expression of MUC1 in the endometrium from polycystic ovary syndrome (PCOS), endometriosis, and fertile women in comparison with other hormone-regulated proteins [hydroxysteroid dehydrogenase (HSD) 1, HSD2, estrogen receptor (ER) and progesterone receptor (PR)]. DESIGN AND PATIENTS: Endometrial samples were obtained from 33 fertile patients, 26 ovulatory PCOS patients, 15 anovulatory PCOS patients, and 25 endometriosis patients. MAIN OUTCOME MEASURE: Immunohistochemistry assessed the expression of MUC1 subunits ER, PR, HSD1, and HSD2 in endometrial epithelium. Endometrial MUC1 expression was quantified by immunoblots and RT-PCR. HSD1 and HSD2 expression was assayed by RT-PCR. RESULTS: MUC1ND expression was significantly higher in ovulatory PCOS than in fertile and anovulatory PCOS patients, even after progesterone stimulation. MUC1ND and -CD expression was lower in anovulatory PCOS than in fertile patients. Only MUC1CD expression was lower in endometriosis patients. Endometrial ER expression was significantly higher in PCOS and endometriosis patients, whereas PR expression was significantly higher in PCOS than in fertile patients. The expression of HSD1 was significantly higher in anovulatory PCOS than in fertile patients. Expression of HSD2 was significantly higher in PCOS patients and lower in endometriosis patients. CONCLUSION: Expression of MUC1 subunits in the infertile endometrium is significantly different from fertile and appears to be a component of altered gene expression that potentially contributes to endometrial insufficiency.


Asunto(s)
Anovulación/metabolismo , Endometriosis/metabolismo , Mucina-1/genética , Síndrome del Ovario Poliquístico/metabolismo , Anovulación/genética , Antígenos de Superficie/genética , Diagnóstico Diferencial , Endometriosis/diagnóstico , Endometriosis/genética , Endometrio/metabolismo , Femenino , Humanos , Proteínas de la Membrana/genética , Mucina-1/metabolismo , Ovulación/fisiología , Síndrome del Ovario Poliquístico/diagnóstico , Síndrome del Ovario Poliquístico/genética , Subunidades de Proteína/genética , Receptores de Estrógenos/genética , Receptores de Progesterona/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
6.
Acta Anaesthesiol Scand ; 54(1): 98-102, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19735495

RESUMEN

BACKGROUND: Simple diagnostic tests are needed to screen septic patients for low cardiac output because intervention is recommended in these patients. We assessed the diagnostic value of central venous oxygen saturation in the superior vena cava (ScvO(2)) for detecting low cardiac output in patients with septic shock. METHODS: We conducted a prospective observational study in three general intensive care units (ICUs) of adult patients with septic shock, who were to have a catheter inserted for thermodilution measurement of cardiac index (CI(TD)). Paired measurements of CI(TD) and central venous oximetry values were obtained when the clinician first measured CI(TD). RESULTS: We included 56 patients with septic shock and a mean sequential organ failure assessment score of 12 (range 3-20). Baseline CI(TD) was 3.5 l/min/m(2) (1.0-6.2) and ScvO(2) of 70% (33-87). The best cut-off of ScvO(2) for CI(TD)>2.5 l/min/m(2) (n=42) was a value >or=64% with positive and negative predictive values of 91% (95% confidence interval 79-98) and 91% (59-100), respectively. The diagnostic values were not improved by using instead central venous O(2) tension or the difference between arterial and central venous O(2) saturation. CONCLUSIONS: This prospective, observational study found that a ScvO(2) measurement of >or=64% indicated CI(TD)>2.5 l/min/m(2) in ICU patients with septic shock.


Asunto(s)
Gasto Cardíaco Bajo/diagnóstico , Oximetría/métodos , Oxígeno/sangre , Choque Séptico/fisiopatología , Adulto , Cateterismo Venoso Central , Humanos , Valor Predictivo de las Pruebas , Estudios Prospectivos , Vena Cava Superior , Adulto Joven
7.
Hum Reprod ; 24(11): 2767-77, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19625313

RESUMEN

BACKGROUND: L-selectin ligands, localized to the luminal epithelium at the time of implantation, may support the early stages of blastocyst attachment. We have assessed the expression of two L-selectin ligands, defined by MECA-79 and HECA-452 monoclonal antibodies, and the sulfotransferase GlcNAc6ST-2, involved in generation of L-selectin ligand epitopes, in the secretory phase of the endometrium from fertile and infertile patients. METHODS: Endometrial samples were obtained from 33 fertile, 26 PCOS, 25 endometriosis and 33 patients diagnosed with unexplained infertility. L-selectin ligands and GlcNAc6ST-2 expression was assessed by immunohistochemistry and immunoblotting. RESULTS: Immunohistochemical staining of uterine epithelium, from fertile and infertile women, demonstrated differential expression of MECA-79 and HECA-452 epitopes. In fertile women in the secretory phase MECA-79 was more strongly expressed, particularly on the lumen, than in infertile women. HECA-452 staining was significantly stronger in the glands in PCOS and endometriosis patients than in fertile women. GlcNAc6ST-2 expression was reduced in infertile patients, correlating with MECA-79 expression. CONCLUSIONS: This study demonstrated significant differences in expression of L-selectin ligands between fertile and infertile women in natural cycles, and could contribute to patient assessment prior to initiating fertility treatment.


Asunto(s)
Endometrio/metabolismo , Infertilidad Femenina/metabolismo , Selectina L/metabolismo , Adulto , Antígenos de Superficie/metabolismo , Implantación del Embrión , Femenino , Humanos , Inmunohistoquímica , Ligandos , Proteínas de la Membrana/metabolismo , Factores de Tiempo
8.
BJOG ; 114(11): 1326-34, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17903232

RESUMEN

Toll-like receptors (TLR) have emerged as key upstream mediators of inflammation at many tissue sites in humans. Inflammatory processes are involved in the process of parturition suggesting that TLR activity within gestation-associated tissues might have an important role in the initiation and/or maintenance of normal term labour and in various pathological states of pregnancy such as infection-associated preterm labour. Either TLRs or their signalling molecules might be excellent therapeutic targets for prevention of preterm labour.


Asunto(s)
Citocinas/fisiología , Trabajo de Parto/fisiología , Trabajo de Parto Prematuro/etiología , Receptores Toll-Like/fisiología , Amnios/fisiología , Comunicación Celular/fisiología , Cuello del Útero/fisiología , Decidua/fisiología , Membranas Extraembrionarias/fisiología , Femenino , Humanos , Trabajo de Parto Prematuro/metabolismo , Placenta/fisiología , Embarazo , Contracción Uterina/fisiología
9.
Gynecol Obstet Invest ; 62(4): 206-16, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16785734

RESUMEN

Infertility is an increasing problem all over the world, and it has been estimated that 10-15% of couples in fertile age have fertility problems. Likewise induced unsafe abortion is a serious threat to women's health. Despite advances made in assisted reproduction techniques, little progress has been made in increasing the success rate during fertility treatment. This document describes a wide range of projects carried out to increase the understanding in the field of embryo implantation research. The 'Fruitful' research network was created to encourage collaborations within the consortium and to describe our different research potentials to granting agencies or private sponsors.


Asunto(s)
Implantación del Embrión/fisiología , Infertilidad Femenina/fisiopatología , Animales , Investigación Biomédica , Modelos Animales de Enfermedad , Implantación del Embrión/efectos de los fármacos , Endometrio/fisiología , Femenino , Humanos , Embarazo , Técnicas Reproductivas Asistidas , Trofoblastos/fisiología
10.
Reproduction ; 131(4): 733-42, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16595724

RESUMEN

Oestrogen, progesterone and paracrine signals from the embryo have been associated with the overall control of implantation. Changes in the expression of the heavily glycosylated transmembrane glycoprotein MUC1 mucin on the endometrial epithelium are also thought to be important for embryo attachment. Increased MUC1 expression has been correlated with elevated progesterone levels in the secretory phase of the menstrual cycle. Embryonic control of endometrial receptivity through changes in MUC1 expression could be achieved through the interleukin-1 system. Four endometrial epithelial cell lines (HEC1A, HEC1B, Ishikawa and RL592) were treated with oestrogen and progesterone (with or without interleukin-1-beta) and were subjected to immunocytochemistry and flow cytometric analysis to determine MUC1 production using MUC1 antibodies. HEC1A (oestrogen receptor (ER) and progesterone receptor (PR) positive) and HEC1B (ER positive and PR negative) were transfected with the MUC1 promoter, underwent similar treatment regimes and the activity of the MUC1 promoter relative to their untreated controls was determined using a chloramphenicol acetyltransferase (CAT) enzyme-linked immunoassay. Using the cell lines, we determined that endometrial MUC1 expression is up-regulated by progesterone, consistent with the in vivo increases in MUC1 related to high progesterone levels. We also revealed that neither oestrogen, nor interleukin-1-beta, appear to modulate MUC1. Progesterone-dependent regulation of MUC1 is likely to be an important factor in determining endometrial receptivity.


Asunto(s)
Antígenos de Neoplasias/genética , Endometrio/metabolismo , Células Epiteliales/metabolismo , Interleucina-1/farmacología , Mucinas/genética , Progesterona/farmacología , Antígenos de Neoplasias/análisis , Línea Celular Tumoral , Endometrio/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Estrógenos/farmacología , Femenino , Citometría de Flujo/métodos , Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica/métodos , Mucina-1 , Mucinas/análisis , Regiones Promotoras Genéticas , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Regulación hacia Arriba
11.
Mol Reprod Dev ; 72(2): 216-29, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15971251

RESUMEN

Changes in the surface epithelium of the endometrium, characterized in part by alterations in cell-surface molecules, sex steroid receptors and the appearance of pinopodes, coincide with the window of endometrial receptivity in the menstrual cycle. This study was performed to evaluate the usefulness of hematoxylin and eosin staining, scanning and transmission microscopy, and MUC1 glycoform, sex steroid receptor, and interleukin receptor (type 1) expression as biomarkers of endometrial receptivity using carefully characterized clinical fertile and infertile groups of women. Using a combination of immunohistochemistry and scanning electron microscopy (SEM) called scanning immunoelectron microscopy (SIM), we confirmed that MUC1 mucin was not associated with the endometrial pinopodes, which have been linked with embryo adhesion. We also showed that failure of embryo implantation was associated with an abnormal endometrial expression of MUC1 mucin, and retention of nuclear progesterone receptor (PR) particularly in epithelial cells. Hematoxylin and eosin staining, transmission electron microscopy (TEM), SEM in isolation and immunohistochemistry for interleukin receptor were not shown to be useful markers. Progesterone-dependent regulation of MUC1 appears to be an important factor in determining endometrial receptivity.


Asunto(s)
Endometrio/metabolismo , Fertilidad/genética , Regulación de la Expresión Génica , Infertilidad Femenina/enzimología , Infertilidad Femenina/genética , Mucina-1/metabolismo , Biomarcadores/metabolismo , Endometrio/ultraestructura , Femenino , Glicosilación , Humanos , Inmunohistoquímica , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Microscopía Inmunoelectrónica , Isoformas de Proteínas/metabolismo , Receptores de Interleucina-1/metabolismo
12.
J Clin Endocrinol Metab ; 87(6): 2581-8, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12050218

RESUMEN

Differentiation of human endometrium during the secretory phase of the menstrual cycle is characterized by expression of a variety of genes implicated in the establishment and maintenance of pregnancy. An increased abundance of signal transducers and activators of transcription (Stats) in the secretory phase suggests Stat5 as a component of the differentiation of endometrium in response to ovarian hormone stimulation in vivo. Decidualization is initiated in a subset of endometrial stromal cells (ESC) in vivo during the secretory phase, but it is unclear whether regulated expression of Stat5 is a feature of these cells. Here, therefore, the abundance and subcellular distribution of Stat5 in ESC after a decidualization stimulus of cAMP plus medroxyprogesterone acetate (MPA) has been investigated in vitro. Western blotting revealed an increase in the apparent abundance of Stat5a and Stat5b, in the cytosolic and nuclear fractions, at 2, 3, and 4 d after stimulation. The potential functional relevance of this increase in Stat5 is suggested by the ability of transiently transfected Stat5a or Stat5b to significantly enhance the response of the decidual PRL promoter to cAMP/MPA and attenuation of the response to cAMP/MPA by dominant negative Stat5. Recent evidence suggests endometrial differentiation, including PRL production, as a possible target of antiphospholipid antibodies (aPL) prevalent in recurrent miscarriage. Monoclonal antibody, ID2, which has similar reactivity as human aPL, significantly decreased the apparent abundance of nuclear Stat5b in response to cAMP/MPA and was associated with decreased decidual PRL promoter activation and PRL secretion. Regulated expression of Stat5 is therefore a component of decidual differentiation of human ESC and contributes significantly to activation of the decidual PRL promoter. Alteration of this process by an aPL component suggests decidual differentiation as a potential clinical target in recurrent early miscarriages.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Endometrio/metabolismo , Proteínas de la Leche , Prolactina/metabolismo , Células del Estroma/metabolismo , Transactivadores/fisiología , Anticuerpos Antifosfolípidos/farmacología , Diferenciación Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Proteínas de Unión al ADN/genética , Decidua/fisiología , Endometrio/citología , Femenino , Humanos , Factor de Transcripción STAT5 , Transactivadores/genética , Transcripción Genética , Proteínas Supresoras de Tumor
13.
Mol Hum Reprod ; 7(6): 581-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11385114

RESUMEN

Human labour is associated with the up-regulation of prostaglandins within the uterus, synthesized via the type-2 cyclo-oxygenase enzyme (COX-2). These lead to remodelling of the fetal membranes and cervix and to stimulation of myometrial contractions. In the human, the principal source of prostaglandins is the amnion. Progesterone acts to promote myometrial quiescence, and in many species the onset of labour is preceded by withdrawal of progesterone. Humans show no systemic progesterone withdrawal, although biochemical changes within the uterus are similar to those in other species. A mutual negative interaction between the transcription factor nuclear factor (NF)-kappaB and the progesterone receptor (PR) has been reported. Using transient transfections and assays for transcriptional activation and promoter binding, we have shown that there is constitutive activity of NF-kappaB in amnion cells at the time of labour, and that COX-2 expression depends upon NF-kappaB. In cells obtained before labour, in which NF-kappaB activity is low, increasing the concentration of PR represses NF-kappaB dependent transcription, while stimulation with IL-1beta both increases NF-kappaB activity and represses PR activity. Our data suggest that human labour is associated with constitutive NF-kappaB activity within the amnion, which functions to increase the expression of COX-2 and appears to contribute to the 'functional progesterone withdrawal'.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Isoenzimas/genética , Trabajo de Parto/metabolismo , FN-kappa B/metabolismo , Progesterona/fisiología , Prostaglandina-Endoperóxido Sintasas/genética , Células Cultivadas , Ciclooxigenasa 2 , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Proteínas de la Membrana , FN-kappa B/genética , Embarazo , Progesterona/metabolismo , Progesterona/farmacología , Regiones Promotoras Genéticas , Pirazoles
14.
Lancet ; 357(9265): 1336-7, 2001 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-11343742

RESUMEN

In man and some animals regulation of embryo implantation by endometrial expression of the highly polymorphic MUC 1 mucin has been suggested. We assessed the polymorphism of MUC 1 in women known to be fertile and those with infertility due to suspected failure of embryo implantation. The median of the lower allele size in the infertile group was only 2.5 kb compared with 3.4 kb in the fertile group (p=0.0029, difference 0.9, [95% CI 0.1-1.3]). Women with unexplained infertility might have a genetic susceptibility to failure of embryo implantation due to small MUC 1 allele size.


Asunto(s)
Infertilidad Femenina/genética , Mucina-1/genética , Polimorfismo Genético , Adulto , Alelos , Southern Blotting , Transferencia de Embrión , Femenino , Predisposición Genética a la Enfermedad , Humanos , Proyectos Piloto , Estadísticas no Paramétricas
16.
Ultramicroscopy ; 84(3-4): 149-57, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10945326

RESUMEN

Using a near-field scanning optical microscope (NSOM), crystals of zinc-porphyrin network materials are characterized with respect to morphology and fluorescence. Needle-shaped crystals are observed. While the topography is flat, the fluorescence intensity profile in the width direction is approximately triangular. A numerical calculation shows that differences between the topographic and optical images cannot be due to an artifact. In some needle-shaped crystals, the fluorescence emission is strongly peaked at one or both ends, possibly indicating a polar crystal structure.


Asunto(s)
Metaloporfirinas/química , Microscopía de Fuerza Atómica/métodos , Microscopía Fluorescente/métodos , Zinc/química , Cristalización
17.
Endocrinology ; 140(10): 4809-20, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10499541

RESUMEN

Human endometrial stromal (ES) cells in culture express PRL, a marker of decidualization, in response to sustained activation of protein kinase A (PKA). Cotreatment with the progestin medroxyprogesterone acetate (MPA) enhanced decidual PRL gene activation in the presence of elevated intracellular cAMP levels. This synergy became apparent, at protein and promoter level, after a lag period of 2 days and increased in a time-dependent manner thereafter. Pretreatment with cAMP advanced the time at which synergy between cAMP and MPA was apparent, suggesting that PKA activation sensitized ES cells to the effects of progestins. Analysis of the progesterone receptor (PR) indicated that PR-A was the predominant form in differentiating ES cells, but its abundance decreased markedly during the course of the decidualization response. The decline in PR levels was of functional relevance, as expression of PR-B or PR-A, by transient transfection, dramatically inhibited the activity of a decidual PRL promoter-reporter construct in response to cAMP. Furthermore, the expression of endogenous PRL protein in response to cAMP or cAMP plus MPA was substantially decreased by constitutive expression of green fluorescence protein-tagged PR, which was localized in the nucleus even in the absence of added ligand. Ligand-independent PR inhibition of the decidual PRL promoter was receptor specific, independent of known PR phosphorylation sites, and required minimally a functional DNA-binding domain. Transient expression of steroid receptor coactivator-1e (SRC-1e), but not SRC-1a, allowed synergy between cAMP and MPA without the requirement of sensitization by pretreatment with cAMP. This raised the possibility that SRC-1e was a component of cAMP-dependent sensitization of ES cells, but there was no evidence of altered messenger RNA expression of either SRC-1 isoform during decidualization. In conclusion, cellular PR levels determine the onset of the decidualization response. Initiation of this process requires elevated intracellular cAMP levels that sensitize ES cells to the actions of progestins through down-regulation of cellular PR levels and possibly via modulation of function of an intermediate factor(s) such as SRC-1e.


Asunto(s)
Decidua/metabolismo , Endometrio/citología , Prolactina/metabolismo , Receptores de Progesterona/fisiología , Células del Estroma/citología , Diferenciación Celular/fisiología , AMP Cíclico/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/fisiología , Femenino , Histona Acetiltransferasas , Antagonistas de Hormonas/farmacología , Humanos , Acetato de Medroxiprogesterona/farmacología , Coactivador 1 de Receptor Nuclear , Progestinas/antagonistas & inhibidores , Progestinas/fisiología , Prolactina/genética , Regiones Promotoras Genéticas/efectos de los fármacos , Regiones Promotoras Genéticas/fisiología , Factores de Transcripción/metabolismo
18.
FEBS Lett ; 452(3): 223-7, 1999 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-10386595

RESUMEN

Lipid-impregnated collodion (nitrocellulose) films have been frequently used as a fusion substrate in the measurement and analysis of electrogenic activity in biological membranes and proteoliposomes. While the method of fusion of biological membranes or proteoliposomes with such films has found a wide application, little is known about the structures formed after the fusion. Yet, knowledge of this structure is important for the interpretation of the measured electric potential. To characterize structures formed after fusion of membrane vesicles (chromatophores) from the purple bacterium Rhodobacter sphaeroides with lipid-impregnated collodion films, we used near-field scanning optical microscopy. It is shown here that structures formed from chromatophores on the collodion film can be distinguished from the lipid-impregnated background by measuring the fluorescence originating either from endogenous fluorophores of the chromatophores or from fluorescent dyes trapped inside the chromatophores. The structures formed after fusion of chromatophores to the collodion film look like isolated (or sometimes aggregated, depending on the conditions) blisters, with diameters ranging from 0.3 to 10 microm (average approximately 1 microm) and heights from 0.01 to 1 microm (average approximately 0.03 microm). These large sizes indicate that the blisters are formed by the fusion of many chromatophores. Results with dyes trapped inside chromatophores reveal that chromatophores fused with lipid-impregnated films retain a distinct internal water phase.


Asunto(s)
Cromatóforos Bacterianos/ultraestructura , Colodión , Proteínas del Complejo del Centro de Reacción Fotosintética/ultraestructura , Cromatóforos Bacterianos/metabolismo , Calcio/farmacología , Vidrio , Lípidos , Fusión de Membrana/efectos de los fármacos , Microscopía de Fuerza Atómica/métodos , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Rhodobacter sphaeroides/metabolismo , Rhodobacter sphaeroides/ultraestructura
19.
Cytokine ; 10(6): 432-40, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9632529

RESUMEN

The cytokine tumour necrosis factor alpha (TNF-alpha) is implicated in the regulation of diverse gynaecological cell types, its biological activity being potentially mediated by two distinct cell surface receptors (TNFR) of molecular weight 55 and 75 kDa, respectively. In this study the sensitivity to the growth regulatory properties of TNF-alpha of a panel of human cervical, endometrial and ovarian cancer cell lines was investigated in relation to the expression and biological activity of the 55- and 75-kDa receptor. There was no evidence of expression or function of the 75-kDa receptor in any of the cell lines tested. The expression and biological activity of the 55-kDa receptor was demonstrated in each TNF sensitive cell line, with one exception, the HOG-1 cervical cancer cell line. The data suggest that the 55-kDa receptor mediates the cellular response to TNF-alpha in sensitive gynaecological cancer cell lines but raises the possibility of the presence of a distinct receptor in HOG-1 cells.


Asunto(s)
Neoplasias de los Genitales Femeninos/metabolismo , Receptores del Factor de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Anticuerpos/farmacología , División Celular/efectos de los fármacos , Neoplasias Endometriales/metabolismo , Neoplasias Endometriales/patología , Femenino , Citometría de Flujo , Neoplasias de los Genitales Femeninos/patología , Humanos , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Reacción en Cadena de la Polimerasa , Receptores del Factor de Necrosis Tumoral/inmunología , Células Tumorales Cultivadas , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología
20.
Biochim Biophys Acta ; 1349(3): 275-84, 1997 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-9434142

RESUMEN

In pre-labelled A549 cells the tumour promoter thapsigargin (50 nM) stimulates the release of [5,6,8,9,11,12,14,15-3H(N)]-arachidonic acid (3H-AA) by ca. 300% above basal levels. A549 cells are estrogen receptor negative (ER-), yet this stimulation by thapsigargin is inhibited in a dose-dependent manner by a 3 h pre-treatment with the anti-estrogen tamoxifen (1-20 microM). Moreover, the presence of excess (100 microM) estradiol does not reverse this effect of tamoxifen. Thapsigargin stimulated 3H-AA release is not inhibited over the same concentration range by 4 hydroxy-tamoxifen nor by the steroidal anti-estrogen ICI 164384. However, the steroidal anti-estrogen ICI 182780 inhibits thapsigargin stimulated 3H-AA release in a similar manner to tamoxifen and this effect is also not reversed by the presence of excess estradiol. Stimulation of 3H-AA release by EGF (10 nM), IL-1beta (1 ng ml-1) and bradykinin (100 nM) was unaffected by these concentrations of tamoxifen. Ionomycin (10 microM) stimulates 3H-AA release by ca. 700% and A23187 (10 microM) by ca. 300% above basal levels. Pre-treatment with tamoxifen (1-20 microM) inhibits 3H-AA release stimulated by both these agents and again the presence of excess estradiol does not reverse this effect. Unlike the effects of glucocorticoids on 3H-AA release in A549 cells the effects of tamoxifen are not reversed by neutralizing anti-bodies to lipocortin 1. Arachidonic acid release is central to cell proliferation in A549 cells and we propose that this action of tamoxifen could explain the anti-proliferative effect seen in these cells and could have important implications for control of cell proliferation of ER- cells in general.


Asunto(s)
Ácido Araquidónico/metabolismo , Receptores de Estrógenos/metabolismo , Tamoxifeno/farmacología , Tapsigargina/farmacología , Anexina A1/fisiología , Bradiquinina/farmacología , Calcimicina/farmacología , División Celular/efectos de los fármacos , Membrana Celular/enzimología , Activación Enzimática , Factor de Crecimiento Epidérmico/farmacología , Antagonistas de Estrógenos/farmacología , Humanos , Interleucina-1/farmacología , Ionomicina/farmacología , Fosfolipasas A/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Células Tumorales Cultivadas
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