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1.
Arch Gynecol Obstet ; 305(4): 1105-1113, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35113234

RESUMEN

OBJECTIVE: This study aimed at assessing perioperative results of robot-assisted laparoscopy (RAL) in the context of deep infiltrating endometriosis (DIE). METHODS: This retrospective French multicentric study included all patients with DIE who underwent surgical treatment managed by RAL (Da Vinci® System). From November 2008 to June 2019, patients were included in a single European database, in Robotic Assisted Laparoscopic Gynecologic Surgery, with Society of European Robotic Gynecological Surgery collaboration. Patients had different DIE sites as follows: gynecological, urological, or digestive, or combinations of these. Surgical procedures and perioperative complications were evaluated. To assess complications, patients were divided into the following four groups according to surgical procedure and DIE site: gynecological only; gynecological and urological; gynecological and digestive; and gynecological, urological, and digestive. RESULTS: A total of 460 patients treated at one of eight health-care facilities from November 2008 to June 2019 were included. Median operative time was 245 min (IQR 186-320), surgeon console time was 138 ± 75 min and estimated blood loss was 70.0 mL ± 107 mL. Among this patient sample, 42.1% had a multidisciplinary surgical approach with a digestive or urology surgeon in addition to gynecology surgeon (25.5% and 16.6% of cases, respectively). Among those with intraoperative complications (n = 25, 5.4%) were primarily conversion to laparotomy (n = 6, 2.0%), transfusion (n = 2, 0.6%), and organ wounds (n = 8, 1.7%). Overall, 5.6% had severe postoperative complications (Clavien-Dindo classification ≥ Grade 3). CONCLUSION: This is among the largest published series addressing RAL for DIE. Interest in this procedure appears promising, with no observed increases in blood loss or in peri- or post-operative complications. DIE laparoscopic surgery can require complex surgical procedures performed by multidisciplinary surgical teams. Thus, it may be one of the best candidates for RAL within gynecology surgery.


Asunto(s)
Endometriosis , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Endometriosis/complicaciones , Endometriosis/cirugía , Femenino , Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Procedimientos Quirúrgicos Ginecológicos/métodos , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos , Resultado del Tratamiento
2.
Ann Surg Oncol ; 27(10): 3891-3897, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32472415

RESUMEN

BACKGROUND: The outcomes of paraaortic lymphadenectomy were compared for the treatment of gynecological malignancies to identify the most appropriate surgical approach. METHODS: Our retrospective, multicentric study included 1304 patients who underwent paraaortic lymphadenectomy for gynecological malignancies. The patients were categorized into the following five groups based on treatment type: transperitoneal laparoscopy (group A, n = 198), extraperitoneal laparoscopy (group B, n = 681), robot-assisted transperitoneal laparoscopy (group C, n = 135), robot-assisted extraperitoneal laparoscopy (group D, n = 44), and laparotomy (group E, n = 246). RESULTS: The prevalence of cancer types differed according to the surgical approach: there were more ovarian cancers in group E and more cervical cancers in groups B and D (p < 0.001). Estimated blood loss was higher in group E (844.2 mL) than in groups treated with minimally invasive interventions (115.8-141.5 mL, p < 0.005). For infrarenal dissection, fewer nodes were removed in group C compared with the other approaches (16 vs. 21 nodes, respectively, p < 0.05). The average operative time ranged from 169 min for group A to 247 min for group E (p < 0.001). Length of hospital stay was 14 days for group E versus 3.5 days for minimally invasive procedures (p < 0.05). The early postoperative grade 3 and superior Dindo-Clavien complications occurred in 9-10% of the patients in groups B-D, 15% of the patients in group E, and only 3% and 4% for groups A and C, respectively. The most common complication was lymphocele. CONCLUSIONS: Laparotomy increases preoperative and postoperative morbidity. The robot-assisted transperitoneal approach demonstrated a poorer lymph node yield than laparotomy and extraperitoneal approaches.


Asunto(s)
Neoplasias de los Genitales Femeninos , Laparoscopía , Robótica , Femenino , Neoplasias de los Genitales Femeninos/cirugía , Humanos , Laparotomía , Escisión del Ganglio Linfático , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados
3.
Artículo en Inglés | MEDLINE | ID: mdl-38007964

RESUMEN

Deep infiltrative endometriosis is a condition affecting up to 15 % of women of childbearing age, defined by extra uterine location of endometrial like tissues. The symptoms of endometriosis range from severe dysmenorrhea to infertility, chronic pelvic pain, bowel dysfunction and urinary tract involvement to name the most common. Endometriosis has an impact on the quality of life of patients, with personal and social consequences. Although medical treatment is indicated in the first instance, surgery may be necessary. Standard laparoscopy has become the gold standard for this surgery. However, surgery for deep infiltrative endometriosis is known to be highly complex, and the significant development of robotic assistance in recent years has had an impact on the evolution of surgical practice. This comprehensive review of the literature provides an overview of the contributions of robotic surgery in the field of endometriosis and gives an insight into the next steps in its development.


Asunto(s)
Endometriosis , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Humanos , Femenino , Endometriosis/complicaciones , Endometriosis/cirugía , Calidad de Vida , Útero
4.
J Hum Nutr Diet ; 26(2): 169-74, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23190418

RESUMEN

BACKGROUND: Inuvialuit of Arctic Canada are at high risk for inadequate vitamin D status as a result of rapid dietary transitions and a lack of solar ultraviolet B exposure. This may have implications for the development of adverse skeletal diseases, cardiovascular diseases and cancers. Data are limited regarding supplement use in Arctic Aboriginal populations. The present study aimed to describe the type and extent of supplement use, emphasising vitamin D, and to identify differences between supplement users and non-users. METHODS: Supplement information was collected from a population-specific quantitative food frequency questionnaire in three communities in the Northwest Territories, Canada, as part of a cross-sectional study. Data were analysed for frequency of supplementation and types of supplements. Users and non-users were compared in terms of age, sex, body mass index, education, marital status, income support, employment and chronic disease diagnosis using nonparametric tests and the chi-squared test. RESULTS: Response rates ranged from 65% to 85%. Included in the analysis were 192 Inuvialuit (45 males, 147 females) with a mean (SD) age of 43.6 (13.9) years. Twenty-three percent reported using a supplement, with multivitamins being the most common. Three percent indicated taking a vitamin D-containing supplement. No significant differences between supplement users and non-users were found. CONCLUSIONS: Despite limited sun exposure for many months of the year, a small proportion of Inuvialuit adults were using supplements, and specifically vitamin D-containing supplements. Future population-based intervention strategies should promote consumption of vitamin D rich foods and encourage the use of vitamin D supplements if diet alone is unable to meet recommendations.


Asunto(s)
Suplementos Dietéticos , Conductas Relacionadas con la Salud , Inuk , Vitamina D/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Regiones Árticas/epidemiología , Índice de Masa Corporal , Estudios Transversales , Conductas Relacionadas con la Salud/etnología , Humanos , Micronutrientes/administración & dosificación , Persona de Mediana Edad , Territorios del Noroeste/epidemiología , Obesidad/epidemiología , Sobrepeso/epidemiología , Riesgo , Encuestas y Cuestionarios , Vitamina D/uso terapéutico , Deficiencia de Vitamina D/epidemiología , Deficiencia de Vitamina D/etnología , Deficiencia de Vitamina D/prevención & control , Adulto Joven
5.
Osteoporos Int ; 22(5): 1633-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20593165

RESUMEN

SUMMARY: This study investigated the influence of ovarian hormone deficiency on core circadian regulatory protein (CCRP) in the context of bone loss. Our data suggest that ovarian hormone deficiency disrupts diurnal rhythmicity and CCRP expression in bone. Further studies should determine if chronobiology provides a novel therapeutic target for osteoporosis intervention. INTRODUCTION: CCRP synchronize metabolic activities and display an oscillatory expression profile in murine bone. In vitro studies using bone marrow mesenchymal stromal/stem cells have demonstrated that the CCRP is present and can be regulated within osteoblast progenitors. In vivo studies have shown that the CCRP regulates bone mass via leptin/neuroendocrine pathways. The current study used an ovariectomized murine model to test the hypothesis that ovarian hormone deficiency is associated with either an attenuation and/or temporal phase shift of the CCRP oscillatory expression in bone and that these changes are correlated with the onset of osteoporosis. METHODS: Sham-operated controls and ovariectomized female C57BL/6 mice were euthanized at 4-h intervals 2 weeks post-operatively. RESULTS: Ovariectomy attenuated the oscillatory expression of CCRP mRNAs in the femur and vertebra relative to the controls and reduced the wheel-running activity profile. CONCLUSION: Ovarian hormone deficiency modulates the expression profile of the CCRP with potential impact on bone marrow mesenchymal stem cell lineage commitment.


Asunto(s)
Péptidos y Proteínas de Señalización del Ritmo Circadiano/biosíntesis , Ritmo Circadiano/fisiología , Estrógenos/fisiología , Osteoporosis/fisiopatología , Animales , Ritmo Circadiano/genética , Péptidos y Proteínas de Señalización del Ritmo Circadiano/genética , Modelos Animales de Enfermedad , Estrógenos/deficiencia , Femenino , Fémur/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica/fisiología , Vértebras Lumbares/metabolismo , Ratones , Ratones Endogámicos C57BL , Actividad Motora/fisiología , Osteoporosis/genética , Osteoporosis/metabolismo , Ovariectomía , ARN Mensajero/genética , Estrés Mecánico , Microtomografía por Rayos X/métodos
6.
Int J Obes (Lond) ; 33(9): 971-7, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19597517

RESUMEN

OBJECTIVE: Circadian mechanisms underlie the physiology of mammals as an adaptation to the earth's rotation on its axis. Highly conserved core circadian regulatory proteins (CCRPs) maintain an oscillatory expression profile in the central and peripheral tissues. The CCRP include both a positive and negative arm, as well as downstream transcriptional regulators. Recent studies in murine models have determined that the mRNAs encoding the CCRP are present in multiple adipose tissue depots and exhibit a robust oscillatory expression profile. This study set out to examine the expression of CCRP mRNAs in human subcutaneous adipose tissues. DESIGN: Retrospective analysis of total RNA isolated from subcutaneous adipose tissue. SUBJECTS: A total of 150 healthy female and male lean (body mass index (BMI) <25), overweight (BMI between 25 and 29.99) or obese (BMI >30) subjects of varied ethnic backgrounds undergoing elective liposuction or surgical procedures. RESULTS: The expression of the CCRP mRNAs displayed a significant correlation between each other and mRNAs representative of adipogenic biomarkers. Hierarchical cluster analyses of mRNAs isolated from the cohort of female Caucasian subjects (n=116) identified three major clusters based on expression of downstream CCRP mRNAs. The mRNAs encoding D site of albumin promoter-binding protein (DBP), E4 promoter-binding protein 4 (E4BP4), PPARgamma coactivator-1beta (PGC-1beta) and Rev-erbalpha were negatively correlated with BMI in a lean cluster (n=66), positively correlated with BMI in a younger overweight/obese cluster (n=19), and not significantly correlated with BMI in an older, overweight/obese cluster (n=31). CONCLUSIONS: These data confirm and extend findings that link the CCRP and circadian mechanisms to the risk of obesity.


Asunto(s)
Índice de Masa Corporal , Péptidos y Proteínas de Señalización del Ritmo Circadiano/metabolismo , Expresión Génica/genética , ARN Mensajero/metabolismo , Grasa Subcutánea/metabolismo , Adulto , Factores de Edad , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Péptidos y Proteínas de Señalización del Ritmo Circadiano/genética , Análisis por Conglomerados , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Exodesoxirribonucleasas , Femenino , Humanos , Masculino , Ratones , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/metabolismo , Estudios Retrospectivos , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
7.
Gynecol Obstet Fertil ; 37(3): 246-51, 2009 Mar.
Artículo en Francés | MEDLINE | ID: mdl-19246234

RESUMEN

Acute fatty liver of pregnancy (AFLP) is a rare disease of which prognosis could be adverse if diagnosis is delayed. Certain diagnosis is sometimes made complex because of undercurrent symptoms with pre-eclampsia or hemolysis, elevated liver enzyme, low platelet (HELLP) syndrome. Several reports announce an increase of incidence and illustrate cases confirmed by non-invasive methods. They permit early diagnosis and improve morbidity and mortality. Reviewing seven of the most important series of AFLP, we demonstrate how to use ultrasonography or computed tomography scan to confirm AFLP. However, liver biopsy should be realised after delivery in case of uncertain diagnosis.


Asunto(s)
Hígado Graso/diagnóstico , Complicaciones del Embarazo/diagnóstico , Biopsia con Aguja , Diagnóstico Diferencial , Hígado Graso/diagnóstico por imagen , Femenino , Síndrome HELLP , Humanos , Hígado/patología , Imagen por Resonancia Magnética , Embarazo , Complicaciones del Embarazo/diagnóstico por imagen , Factores de Tiempo , Tomografía Computarizada por Rayos X , Ultrasonografía
8.
Biochim Biophys Acta Gen Subj ; 1863(11): 129410, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31401178

RESUMEN

BACKGROUND: Neurodegenerative disorders, such as Parkinson's disease (PD), are characterized by neuronal death involving, among other events, mitochondrial dysfunction and excitotoxicity. Along these lines, several attempts have been made to slow this pathology but none have been yet discovered. Based on its capacity to cross the blood-brain barrier and provide neuronal protection in vitro and in vivo, the pituitary adenylate cyclase-activating polypeptide (PACAP) represents a promising lead molecule. Pharmacological studies showed that PACAP interacts with three different G protein-coupled receptors, i.e. PAC1, VPAC1 and VPAC2. However, only PAC1 is associated with neuronal anti-apoptotic actions, whilst VPAC activation might cause adverse effects. In the context of the development of PAC1-selective agonists, PACAP(1-23) (PACAP23) appears as the shortest known PACAP bioactive fragment. METHODS: Hence, the capacity of this peptide to bind PACAP receptors and protect neuroblastoma cells was evaluated under conditions of mitochondrial dysfunction and glutamate excitotoxicity. In addition, its ability to activate downstream signaling events involving G proteins (Gαs and Gαq), EPAC, and calcium was also assessed. RESULTS: Compared to the endogenous peptide, PACAP23 showed a reduced affinity towards PAC1, although this fragment exerted potent neuroprotection. However, surprisingly, some disparities were observed for PACAP23 signaling compared to full length PACAP, suggesting that downstream signaling related to neuroprotection is distinctly regulated following subtle differences in their PAC1 interactions. CONCLUSIONS: Altogether, this study demonstrates the potent neuroprotective action of amidated PACAP23. GENERAL SIGNIFICANCE: PACAP23 represents an attractive template for development of shorter PACAP-derived neuroprotective molecules.


Asunto(s)
Señalización del Calcio/efectos de los fármacos , Fármacos Neuroprotectores , Péptidos , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Animales , Células CHO , Cricetulus , Humanos , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Péptidos/química , Péptidos/farmacología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/química , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/farmacología , Receptores de Tipo II del Péptido Intestinal Vasoactivo/metabolismo , Receptores de Tipo I del Polipéptido Intestinal Vasoactivo/metabolismo
9.
J Radiol ; 89(7-8 Pt 1): 863-71, 2008.
Artículo en Francés | MEDLINE | ID: mdl-18772748

RESUMEN

PURPOSE: To demonstrate the added diagnostic value of time-resolved imaging of contrast kinetics (TRICKS) in the evaluation of lower limb arteries compared to standard 3 level MRA with stepping table method. PATIENTS AND METHODS: Forty patients (30% diabetics) with lower extremity peripheral arterial disease (87.5% with chronic ischemia) underwent standard contrast MRA including TRICKS of the distal arteries. Five arterial segments were defined per leg, and 395 arterial segments were compared (one patient with amputation). Two reviewers evaluated the quality of arterial imaging, presence of venous return and degree of stenosis per segment. The degree of interobserver agreement for arterial stenosis measurement was calculated. RESULTS: More arterial segments could be analyzed on the TRICKS sequence (good or excellent analysis in 63.03%-66.32% of arterial segments compared to 41.51%-47.08% on routine MRA). There was less venous contamination on TRICKS images (25.57% to 27.60% gain). The degree of interobserver agreement was superior with TRICKS compared to standard MRA (kappa 0.85 vs 0.69). CONCLUSION: The TRICKS sequence can be added to standard MRA for pre-therapeutic evaluation of distal arteries in patients with peripheral arterial disease, especially with chronic ischemic with rest pain and/or trophic changes.


Asunto(s)
Pierna/irrigación sanguínea , Angiografía por Resonancia Magnética , Enfermedades Vasculares Periféricas/diagnóstico , Anciano , Femenino , Humanos , Angiografía por Resonancia Magnética/métodos , Masculino
10.
J Gynecol Obstet Hum Reprod ; 47(5): 179-181, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29510272

RESUMEN

Endometriosis is a common condition that causes pain and infertility. It can lead to absenteeism and also to multiple surgeries with a consequent risk of impaired fertility, and constitutes a major public health cost. Despite the existence of numerous national and international guidelines, the management of endometriosis remains suboptimal. To address this issue, the French College of Gynaecologists and Obstetricians (CNGOF) and the Society of Gynaecological and Pelvic Surgery (SCGP) convened a committee of experts tasked with defining the criteria for establishing a system of care networks, headed by Expert Centres, covering all of mainland France and its overseas territories. This document sets out the criteria for the designation of Expert Centres. It will serve as a guide for the authorities concerned, to ensure that the means are provided to adequately manage patients with endometriosis.


Asunto(s)
Endometriosis/diagnóstico , Endometriosis/terapia , Guías como Asunto/normas , Instituciones de Salud/normas , Sociedades Médicas/normas , Femenino , Francia , Humanos
11.
Gynecol Obstet Fertil Senol ; 46(3): 376-382, 2018 Mar.
Artículo en Francés | MEDLINE | ID: mdl-29490889

RESUMEN

OBJECTIVES: The Collège national des gynécologues obstétriciens français (CNGOF), in agreement with the Société de chirurgie gynécologique et pelvienne (SCGP), has set up a commission in 2017 to define endometriosis expert centres, with the aim of optimizing endometriosis care in France. METHODS: The committee included members from university and general hospitals as well as private facilities, representing medical, surgical and radiological aspects of endometriosis care. Opinion of endometriosis patients' associations was obtained prior to writing this work. The final text was presented and unanimously validated by the members of the CNGOF Board of Directors at its meeting of October 13, 2017. RESULTS: Based on analysis of current management of endometriosis and the last ten years opportunities in France, the committee has been able to define the contours of endometriosis expert centres. The objectives, production specifications, mode of operation, missions and funding for these centres were described. The following missions have been specifically defined: territorial organization, global and referral care, communication and teaching as well as research and evaluation. CONCLUSION: Because of its daily impact for women and its economic burden in France, endometriosis justifies launching of expert centres throughout the country with formal accreditation by health authorities, ideally as part of the National Health Plan.


Asunto(s)
Endometriosis , Centros de Atención Terciaria/organización & administración , Comités Consultivos , Endometriosis/diagnóstico , Endometriosis/terapia , Femenino , Francia , Humanos , Sociedades Médicas
12.
Br J Pharmacol ; 152(7): 1021-32, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17618308

RESUMEN

BACKGROUND AND PURPOSE: Both parasympathetic tone and atrial tachycardia (AT) remodelling of ion channels play important roles in atrial fibrillation (AF) pathophysiology. Different muscarinic cholinergic receptor (mAChR) subtypes (M2, M3, M4) in atrial cardiomyocytes are coupled to distinct K+-currents (called IKM2, IKM3, IKM4, respectively). Pulmonary veins (PVs) are important in AF and differential cholinergic current responses are a potential underlying mechanism. This study investigated AT-induced remodelling of mAChR subtypes and K+-currents in left-atrial (LA) and PV cardiomyocytes. EXPERIMENTAL APPROACH: Receptor expression was assayed by western blot. IKM2, IKM3 and IKM4 were recorded with whole-cell patch-clamp in LA and PV cardiomyocytes of nonpaced control dogs and dogs after 7 days of AT-pacing (400 bpm). KEY RESULTS: Current densities of IKM2, IKM3 and IKM4 were significantly reduced by AT-pacing in LA and PV cardiomyocytes. PV cardiomyocyte current-voltage relations were similar to LA for all three cholinergic currents, both in control and AT remodelling. Membrane-protein expression levels corresponding to M2, M3 and M4 subtypes were decreased significantly (by about 50%) after AT pacing. Agonist concentration-response relations for all three currents were unaffected by AT pacing. CONCLUSIONS AND IMPLICATIONS: AT downregulated all three mAChR-coupled K+-current subtypes, along with corresponding mAChR protein expression. These changes in cholinergic receptor-coupled function may play a role in AF pathophysiology. Cholinergic receptor-coupled K+-currents in PV cardiomyocytes were similar to those in LA under control and AT-pacing conditions, suggesting that differential cholinergic current properties do not explain the role of PVs in AF.


Asunto(s)
Atrios Cardíacos/metabolismo , Miocitos Cardíacos/metabolismo , Canales de Potasio de Rectificación Interna/metabolismo , Venas Pulmonares/metabolismo , Receptores Muscarínicos/metabolismo , Taquicardia Atrial Ectópica/metabolismo , Animales , Fibrilación Atrial/metabolismo , Fibrilación Atrial/fisiopatología , Western Blotting , Estimulación Cardíaca Artificial , Células Cultivadas , Modelos Animales de Enfermedad , Perros , Regulación hacia Abajo , Técnicas Electrofisiológicas Cardíacas , Potenciales Evocados , Atrios Cardíacos/patología , Miocitos Cardíacos/patología , Técnicas de Placa-Clamp , Venas Pulmonares/patología , Receptores Muscarínicos/biosíntesis , Taquicardia Atrial Ectópica/fisiopatología , Factores de Tiempo
13.
Biochim Biophys Acta ; 916(3): 419-27, 1987 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-3689801

RESUMEN

The effects of 1,2-cyclohexanedione and phenylglyoxal on staphylococcal alpha-toxin were studied. Modification of one arginine residue in alpha-toxin was sufficient to render the toxin nonhemolytic with no conformational change. Modified alpha-toxin did not protect cells from hemolysis by native alpha-toxin. An arginine residue is therefore at or near the binding site of alpha-toxin. Trypsin digestion of modified alpha-toxin generated a 20 kDa fragment which was isolated using a boric acid gel column. Upon regeneration, this 20 kDa fragment was not recognized by a population of antibodies which prevented alpha-toxin binding. The fragment was recognized by antibodies directed against post-binding events. However, the antibinding antibodies recognized the intact modified toxin. This leads us to conclude that antibinding determinants are not found directly in the binding site or are conformationally masked.


Asunto(s)
Arginina , Toxinas Bacterianas/antagonistas & inhibidores , Proteínas Hemolisinas , Animales , Ciclohexanonas/farmacología , Ensayo de Inmunoadsorción Enzimática , Hemólisis , Peso Molecular , Fenilglioxal/farmacología , Conejos , Relación Estructura-Actividad , Tripsina/metabolismo
14.
Cell Signal ; 12(9-10): 673-82, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11080620

RESUMEN

In vitro, little specificity is seen for modulation of effectors by different combinations of Gbetagamma subunits from heterotrimeric G proteins. Here, we demonstrate that the coupling of specific combinations of Gbetagamma subunits to different receptors leads to a differential ability to modulate effectors in vivo. We have shown that the beta(1)AR and beta(2)AR can activate homomultimers of the human inwardly rectifying potassium channel Kir 3.2 when coexpressed in Xenopus oocytes, and that this requires a functional mammalian Gs heterotrimer. Modulation was independent of cAMP production, suggesting a membrane-delimited mechanism. To analyze further the importance of different Gbetagamma combinations, we have tested the facilitation of Kir 3.2 activation by betaAR mediated by different Gbetagamma subunits. The subunits tested were Gbeta(1,5) and Ggamma(1,2,7,11). These experiments demonstrated significant variation between the ability of the Gbetagamma combinations to activate the channels after receptor stimulation. This was in marked contrast to the situation in vitro where little specificity for binding of a Kir 3.1 C-terminal GST fusion protein by different Gbetagamma combinations was detected. More importantly, neither receptor, although homologous both structurally and functionally, shared the same preference for Gbetagamma subunits. In the presence of beta(1)AR, Gbeta(5)gamma(1) and Gbeta(5)gamma(11) activated Kir 3.2 to the greatest extent, while for the beta(2)AR, Gbeta(1)gamma(7), Gbeta(1)gamma(11,) and Gbeta(5)gamma(2) produced the greatest responses. Interestingly, no preference was seen in the ability of different Gbetagamma subunits to facilitate receptor-stimulated GTPase activity of the Gsalpha. These results suggest that it is not the receptor/G protein alpha subunit interaction or the Gbetagamma/effector interaction that is altered by Gbetagamma, but rather that the ability of the receptor to interact productively with the Gbetagamma subunit directly and/or the G protein/effector complex is dependent on the specific G protein heterotrimer associated with the receptor.


Asunto(s)
Proteínas de Unión al GTP Heterotriméricas/metabolismo , Canales de Potasio de Rectificación Interna , Canales de Potasio/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Animales , Línea Celular , Canales de Potasio Rectificados Internamente Asociados a la Proteína G , Proteínas de Unión al GTP Heterotriméricas/genética , Humanos , Ratones , Canales de Potasio/genética , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 2/genética , Xenopus
15.
Cell Signal ; 11(7): 523-33, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10405763

RESUMEN

beta 2-Adrenergic receptors expressed in Sf9 cells activate endogenous Gs and adenylyl cyclase [Mouillac B., Caron M., Bonin H., Dennis M. and Bouvier M. (1992) J. Biol. Chem. 267, 21733-21737]. However, high affinity agonist binding is not detectable under these conditions suggesting an improper stoichiometry between the receptor and the G protein and possibly the effector molecule as well. In this study we demonstrate that when beta 2-adrenergic receptors were co-expressed with various mammalian G protein subunits in Sf9 cells using recombinant baculoviruses signalling properties found in native receptor systems were reconstituted. For example, when beta 2AR was co-expressed with the Gs alpha subunit, maximal receptor-mediated adenylyl cyclase stimulation was greatly enhanced (60 +/- 9.0 versus 150 +/- 52 pmol cAMP/min/mg protein) and high affinity, GppNHp-sensitive, agonist binding was detected. When G beta gamma subunits were co-expressed with Gs alpha and the beta 2AR, receptor-stimulated GTPase activity was also demonstrated, in contrast to when the receptor was expressed alone, and this activity was higher than when beta 2AR was co-expressed with Gs alpha alone. Other properties of the receptor, including receptor desensitization and response to inverse agonists were unaltered. Using antisera against an epitope-tagged beta 2AR, both Gs alpha and beta gamma subunits could be co-immunoprecipitated with the beta 2AR under conditions where subunit dissociation would be expected given current models of G protein function. A desensitization-defective beta 2AR (S261, 262, 345, 346A) and a mutant which is constitutively desensitized (C341G) could also co-immunoprecipitate G protein subunits. These results will be discussed in terms of a revised view of G protein-mediated signalling which may help address issues of specificity in receptor/G protein coupling.


Asunto(s)
Subunidades beta de la Proteína de Unión al GTP , Subunidades gamma de la Proteína de Unión al GTP , Proteínas de Unión al GTP/metabolismo , Proteínas de Unión al GTP Heterotriméricas , Receptores Adrenérgicos beta 2/metabolismo , Adenilil Ciclasas/metabolismo , Agonistas Adrenérgicos beta/metabolismo , Animales , Línea Celular , GTP Fosfohidrolasas/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/genética , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Proteínas de Unión al GTP/genética , Humanos , Isoproterenol/metabolismo , Receptores Adrenérgicos beta 2/genética , Transducción de Señal , Spodoptera/citología
16.
Cell Signal ; 11(12): 871-83, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10659995

RESUMEN

To date, no comprehensive study has been done on all combinations of the human homologues of the Kir3.0 channel family, and the human homologue of Kir3.3 has not yet been identified. To obtain support for the contention that most of the functional data on non-human Kir3.0 channels can be extrapolated to human channels, we have cloned the human homologues of the Kir3.0 family, including the yet unidentified human Kir3.3, and the human Kir4.1. The expression pattern of these channels in various human brain areas and peripheral tissues, analysed by Northern blot analysis, allows for the existence of various homomeric and heteromeric forms of human Kir3.0 channels. Expression studies of all possible combinations in Xenopus oocytes indicated that in homomeric Kir3.2c and heteromeric Kir3.1/3.2c channels mediate, in our studies, inward currents with largest amplitude of any other Kir3.0 channel combinations, followed by heteromeric Kir3.1/3.4 and homomeric Kir4.1 channels. Channel combinations which include Kir3.3 are detrimental to the formation of functional channels. The co-expression experiments with different Kir channel subunits indicate the selective formation of certain channel combinations, suggesting that channel specificity is not solely dependent on spatial and temporal regulation of Kir subunit expression.


Asunto(s)
Canales de Potasio de Rectificación Interna , Canales de Potasio/metabolismo , Potasio/metabolismo , Secuencia de Aminoácidos , Animales , Encéfalo/metabolismo , Cerebelo/metabolismo , ADN Complementario/genética , Femenino , Canales de Potasio Rectificados Internamente Asociados a la Proteína G , Proteínas de Unión al GTP/fisiología , Humanos , Activación del Canal Iónico , Transporte Iónico , Ratones , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Oocitos , Especificidad de Órganos , Canales de Potasio/química , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Xenopus laevis
17.
Clin Nephrol ; 63(5): 375-80, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15909597

RESUMEN

The prognosis for adults with acute post-streptococcal glomerulonephritis (PSGN) who present with crescentic glomerulonephritis and nephrotic proteinuria is not known. We report a patient with rapidly progressive glomerulonephritis and nephrotic-range proteinuria following acute pharyngitis, in whom serologic and kidney biopsy findings led to a diagnosis of PSGN. The patient was treated with corticosteroids and anti-hypertensive medications resulting in improvement in renal function and decrease in proteinuria. These results suggest that aggressive treatment of crescentic PSGN with nephrotic syndrome can result in a favorable outcome.


Asunto(s)
Glomerulonefritis/tratamiento farmacológico , Glomerulonefritis/etiología , Metilprednisolona/administración & dosificación , Síndrome Nefrótico/tratamiento farmacológico , Síndrome Nefrótico/etiología , Infecciones Estreptocócicas/complicaciones , Administración Oral , Biopsia con Aguja , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Glomerulonefritis/patología , Humanos , Inmunohistoquímica , Infusiones Intravenosas , Pruebas de Función Renal , Persona de Mediana Edad , Síndrome Nefrótico/patología , Prednisona/administración & dosificación , Quimioterapia por Pulso , Medición de Riesgo , Índice de Severidad de la Enfermedad , Infecciones Estreptocócicas/diagnóstico , Resultado del Tratamiento
18.
J Clin Neurosci ; 12(7): 810-2, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16198921

RESUMEN

The MRI characteristics of an isolated subacute aneurysmal corpus callosum hematoma, without evidence of blood in cerebrospinal fluid (CSF) spaces or ventricles, have not been previously reported. This report highlights the difficulty of accurate diagnosis and treatment in a patient with an unusual ruptured pericallosal aneurysm simulating a corpus callosum tumour. Additionally we analyse the particular radiological configuration and appearance of blood products in this region.


Asunto(s)
Aneurisma Roto/diagnóstico , Neoplasias Encefálicas/diagnóstico , Cuerpo Calloso/patología , Neoplasias/diagnóstico , Adulto , Angiografía Cerebral/métodos , Arterias Cerebrales/patología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos
19.
Cardiovasc Res ; 42(2): 434-42, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10533579

RESUMEN

BACKGROUND: We have shown that rapid atrial activation, as occurs during atrial fibrillation (AF), reduces L-type Ca2+ current (ICa) and that this is the principal mechanism of the action potential duration and refractoriness changes that characterize tachycardia-induced atrial remodeling. The present study was designed to determine whether atrial tachycardia alters biochemical indices of the number of L-type Ca2+ channels and/or of the number and binding affinity of beta-adrenergic receptors. METHODS: In canine atrial sarcolemmal preparations, the number and binding affinity of dihydropyridine receptors were determined with the use of 3H-nitrendipine and that of beta-adrenergic receptors with 125I-iodocyanopindolol. Results were obtained with preparations from dogs paced at 400/min for 1 (P1, n = 20), 7 (P7, n = 9), and 42 (P42, n = 9) days, and compared with observations in sham-operated controls (P0, n = 14). RESULTS: Pacing reduced the Bmax of dihydropyridine receptors, from 157 +/- 18 fmol/mg (P0) to 116 +/- 9 fmol/mg (P1, P < 0.05), 100 +/- 14 fmol/mg (P7, P < 0.05) and 94 +/- 9 fmol/mg (P42, P < 0.01). The affinity of dihydropyridine receptors was unchanged, with the Kd averaging 711 +/- 102 pM. 656 +/- 74 pM, 633 +/- 155 pM and 585 +/- 92 pM in P0, P1, P7 and P42 dogs. Neither Bmax nor Kd of beta-adrenergic receptors was altered by rapid pacing. Values of Bmax of dihydropyridine receptors correlated with atrial ICa current density (r2 = 0.95) and ERP (r2 = 0.99). CONCLUSIONS: Rapid atrial activation results in downregulation in the number of dihydropyridine receptors without altering the number or affinity of beta-adrenergic receptors. The reductions in ICa that play an important role in the atrial electrical remodeling by which 'AF begets AF' appear to be due at least in part to a decrease in the number of L-type Ca2+ channels in cardiac cell membranes.


Asunto(s)
Fibrilación Atrial/metabolismo , Canales de Calcio/metabolismo , Dihidropiridinas/metabolismo , Miocardio/metabolismo , Receptores Adrenérgicos beta/metabolismo , Antagonistas Adrenérgicos beta/farmacología , Análisis de Varianza , Animales , Sitios de Unión , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Estimulación Cardíaca Artificial , Perros , Femenino , Yodocianopindolol/farmacología , Modelos Lineales , Masculino , Nitrendipino/farmacología , Sarcolema/metabolismo , Estadísticas no Paramétricas
20.
Gynecol Obstet Fertil ; 43(7-8): 528-32, 2015.
Artículo en Francés | MEDLINE | ID: mdl-26047969

RESUMEN

The incidence of vulvar intra-epithelial neoplasia (VIN) is increasing in the developed countries especially in young women. There is little consensus regarding the optimal management. Surgery used to be the gold standard. Alternatives to surgery are now needed for the treatment of VIN. Many studies investigated the effectiveness of Imiquimod 5% cream in this pathology. We present a literature review of the results published on the subject.


Asunto(s)
Aminoquinolinas/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma in Situ/tratamiento farmacológico , Neoplasias de la Vulva/tratamiento farmacológico , Carcinoma in Situ/terapia , Femenino , Humanos , Imiquimod , Resultado del Tratamiento , Neoplasias de la Vulva/terapia
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