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1.
Ultrasound Obstet Gynecol ; 60(3): 381-389, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35247287

RESUMEN

OBJECTIVE: To evaluate the performance of third-trimester ultrasound for the diagnosis of clinically significant placenta accreta spectrum disorder (PAS) in women with low-lying placenta or placenta previa. METHODS: This was a prospective multicenter study of pregnant women aged ≥ 18 years who were diagnosed with low-lying placenta (< 20 mm from the internal cervical os) or placenta previa (covering the internal cervical os) on ultrasound at ≥ 26 + 0 weeks' gestation, between October 2014 and January 2019. Ultrasound suspicion of PAS was raised in the presence of at least one of these signs on grayscale ultrasound: (1) obliteration of the hypoechogenic space between the uterus and the placenta; (2) interruption of the hyperechogenic interface between the uterine serosa and the bladder wall; (3) abnormal placental lacunae. Histopathological examinations were performed according to a predefined protocol, with pathologists blinded to the ultrasound findings. To assess the ability of ultrasound to detect clinically significant PAS, a composite outcome comprising the need for active management at delivery and histopathological confirmation of PAS was considered the reference standard. PAS was considered to be clinically significant if, in addition to histological confirmation, at least one of these procedures was carried out after delivery: use of hemostatic intrauterine balloon, compressive uterine suture, peripartum hysterectomy, uterine/hypogastric artery ligation or uterine artery embolization. The diagnostic performance of each ultrasound sign for clinically significant PAS was evaluated in all women and in the subgroup who had at least one previous Cesarean section and anterior placenta. Post-test probability was assessed using Fagan nomograms. RESULTS: A total of 568 women underwent transabdominal and transvaginal ultrasound examinations during the study period. Of these, 95 delivered in local hospitals, and placental pathology according to the study protocol was therefore not available. Among the 473 women for whom placental pathology was available, clinically significant PAS was diagnosed in 99 (21%), comprising 36 cases of placenta accreta, 19 of placenta increta and 44 of placenta percreta. The median gestational age at the time of ultrasound assessment was 31.4 (interquartile range, 28.6-34.4) weeks. A normal hypoechogenic space between the uterus and the placenta reduced the post-test probability of clinically significant PAS from 21% to 5% in women with low-lying placenta or placenta previa in the third trimester of pregnancy and from 62% to 9% in the subgroup with previous Cesarean section and anterior placenta. The absence of placental lacunae reduced the post-test probability of clinically significant PAS from 21% to 9% in women with low-lying placenta or placenta previa in the third trimester of pregnancy and from 62% to 36% in the subgroup with previous Cesarean section and anterior placenta. When abnormal placental lacunae were seen on ultrasound, the post-test probability of clinically significant PAS increased from 21% to 59% in the whole cohort and from 62% to 78% in the subgroup with previous Cesarean section and anterior placenta. An interrupted hyperechogenic interface between the uterine serosa and bladder wall increased the post-test probability for clinically significant PAS from 21% to 85% in women with low-lying placenta or placenta previa and from 62% to 88% in the subgroup with previous Cesarean section and anterior placenta. When all three sonographic markers were present, the post-test probability for clinically significant PAS increased from 21% to 89% in the whole cohort and from 62% to 92% in the subgroup with previous Cesarean section and anterior placenta. CONCLUSIONS: Grayscale ultrasound has good diagnostic performance to identify pregnancies at low risk of PAS in a high-risk population of women with low-lying placenta or placenta previa. Ultrasound may be safely used to guide management decisions and concentrate resources on patients with higher risk of clinically significant PAS. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Placenta Accreta , Placenta Previa , Cesárea , Femenino , Humanos , Placenta/diagnóstico por imagen , Placenta/patología , Placenta Accreta/diagnóstico por imagen , Placenta Accreta/patología , Placenta Previa/diagnóstico por imagen , Placenta Previa/patología , Embarazo , Tercer Trimestre del Embarazo , Diagnóstico Prenatal , Estudios Prospectivos , Estudios Retrospectivos , Ultrasonografía Prenatal/métodos
2.
Ultrasound Obstet Gynecol ; 57(2): 298-304, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32851714

RESUMEN

OBJECTIVE: To assess whether repeat cervical-length (CL) measurement in women discharged from hospital after their first episode of threatened preterm labor can predict their risk of spontaneous preterm birth. METHODS: This was a secondary analysis of a randomized controlled trial of maintenance tocolysis, in which CL was measured on transvaginal ultrasound at the time of hospital discharge and after 2, 4, 8 and 12 weeks, in women who remained undelivered after their first episode of threatened preterm labor. After univariate analysis, multivariate logistic regression analysis was used to assess whether CL < 10 mm at the time of hospital discharge or at any follow-up evaluation could predict spontaneous delivery prior to 37 weeks of gestation. RESULTS: Of 226 women discharged after a diagnosis of threatened preterm labor, 57 (25.2%) delivered spontaneously prior to 37 weeks' gestation. The risk of spontaneous preterm birth was higher among women with CL < 10 mm at hospital discharge compared to those with CL ≥ 10 mm (adjusted odds ratio (aOR), 3.3; 95% CI, 1.2-9.2). Moreover, spontaneous preterm delivery was more common when CL < 10 mm was detected up to 2 weeks (aOR, 2.9; 95% CI, 1.1-7.3) or up to 4 weeks (aOR, 7.3; 95% CI, 2.3-22.8) post discharge, as compared with when CL was persistently ≥ 10 mm. The association was not significant when considering CL measurements at 8 weeks, and there was insufficient information to assess the effect of measurements obtained at 12 weeks. CONCLUSIONS: Women who remain undelivered after their first episode of threatened preterm labor continue to be at high risk of spontaneous preterm birth if their CL is below 10 mm at the time of hospital discharge or at any follow-up visit up to 4 weeks later. CL measurement could be included in the antenatal care of these women in order to stratify their risk of preterm birth, rationalize resource utilization and help clinicians improve pregnancy outcome. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Medición de Longitud Cervical , Trabajo de Parto Prematuro , Nacimiento Prematuro , Diagnóstico Prenatal , Adulto , Femenino , Edad Gestacional , Humanos , Alta del Paciente , Valor Predictivo de las Pruebas , Embarazo , Tercer Trimestre del Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Regresión
3.
Ig Sanita Pubbl ; 76(4): 241-255, 2020.
Artículo en Italiano | MEDLINE | ID: mdl-33161421

RESUMEN

The last few weeks of pregnancy are critical to a baby's health because important organs, including the brain and lungs, are not completely developed until the end of pregnancy. The adverse events during labor and childbirth can have very serious physical, psychological and financial consequences for the child, the family, health professionals and the whole community. These events can be reduced through interventions aimed at improving the safety and quality of care, based on evidence-based knowledge, guidelines and practices that must be widely and effectively applied. This work reports the experience of the Lombardy Region on improvement actions in the obstetric and gynecological procedures for the reduction of adverse events and sentinel events through the monitoring and management of the RCGS trigger tool.


Asunto(s)
Procedimientos Quirúrgicos Ginecológicos/normas , Seguridad del Paciente , Garantía de la Calidad de Atención de Salud/normas , Mejoramiento de la Calidad , Calidad de la Atención de Salud , Niño , Parto Obstétrico , Femenino , Humanos , Ciencia de la Implementación , Lactante , Guías de Práctica Clínica como Asunto , Embarazo
4.
BJOG ; 127(9): 1116-1121, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32339382

RESUMEN

OBJECTIVE: To report mode of delivery and immediate neonatal outcome in women infected with COVID-19. DESIGN: Retrospective study. SETTING: Twelve hospitals in northern Italy. PARTICIPANTS: Pregnant women with COVID-19-confirmed infection who delivered. EXPOSURE: COVID 19 infection in pregnancy. METHODS: SARS-CoV-2-infected women who were admitted and delivered from 1 to 20 March 2020 were eligible. Data were collected from the clinical records using a standardised questionnaire on maternal general characteristics, any medical or obstetric co-morbidity, course of pregnancy, clinical signs and symptoms, treatment of COVID 19 infection, mode of delivery, neonatal data and breastfeeding. MAIN OUTCOME AND MEASURES: Data on mode of delivery and neonatal outcome. RESULTS: In all, 42 women with COVID-19 delivered at the participating centres; 24 (57.1%, 95% CI 41.0-72.3) delivered vaginally. An elective caesarean section was performed in 18/42 (42.9%, 95% CI 27.7-59.0) cases: in eight cases the indication was unrelated to COVID-19 infection. Pneumonia was diagnosed in 19/42 (45.2%, 95% CI 29.8-61.3) cases: of these, 7/19 (36.8%, 95% CI 16.3-61.6) required oxygen support and 4/19 (21.1%, 95% CI 6.1-45.6) were admitted to a critical care unit. Two women with COVID-19 breastfed without a mask because infection was diagnosed in the postpartum period: their newborns tested positive for SARS-Cov-2 infection. In one case, a newborn had a positive test after a vaginal operative delivery. CONCLUSIONS: Although postpartum infection cannot be excluded with 100% certainty, these findings suggest that vaginal delivery is associated with a low risk of intrapartum SARS-Cov-2 transmission to the newborn. TWEETABLE ABSTRACT: This study suggests that vaginal delivery may be associated with a low risk of intrapartum SARS-Cov-2 transmission to the newborn.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/transmisión , Parto Obstétrico/efectos adversos , Transmisión Vertical de Enfermedad Infecciosa , Neumonía Viral/diagnóstico , Neumonía Viral/transmisión , Complicaciones Infecciosas del Embarazo/diagnóstico , Adulto , COVID-19 , Femenino , Humanos , Recién Nacido , Italia , Masculino , Pandemias , Embarazo , Complicaciones Infecciosas del Embarazo/virología , Estudios Retrospectivos , SARS-CoV-2 , Vagina/virología
7.
Ultrasound Obstet Gynecol ; 48(2): 224-31, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26350023

RESUMEN

OBJECTIVE: To investigate the hypothesis that fetal abdominal circumference (AC) and uterine artery (UtA) Doppler pulsatility index (PI) could be used to select two homogeneous subgroups of women affected by hypertensive disorders of pregnancy (HDP), characterized by the coexistence of maternal hypertension with and without intrauterine growth restriction (IUGR). METHODS: This was a multicenter retrospective study of cases affected by HDP in whom fetal AC and UtA-PI had been measured at admission to fetomaternal medicine units. Maternal characteristics, pregnancy complications and outcome were recorded. These data allowed us to model the characteristics of fetal growth in cases affected by HDP, and to design composite indicators of risk factors for maternal metabolic syndrome and of severity for maternal functional organ damage. RESULTS: Measurements of fetal AC and UtA-PI allowed us to define a group of HDP cases with appropriate-for-gestational-age (AGA) fetuses (HDP-AGA), diagnosed by normal fetal AC and UtA-PI (n = 205), and a group of HDP cases with IUGR fetuses (HDP-IUGR), diagnosed by fetal AC < 5(th) centile and UtA-PI > 95(th) centile (n = 124). Curves fitted to the birth weights of these two groups were significantly different, but gestational age at admission for HDP (< 34 or ≥ 34 weeks) did not show an independent association with birth weight. When birth weight was expressed as a Z-score with respect to local reference charts, the average corresponded to the 6(th) and 48(th) centiles, respectively. The occurrence of HDP-AGA (as compared with HDP-IUGR) was significantly associated with risk factors for maternal metabolic syndrome (odds ratio, 2.79 (95% CI, 1.57-4.97)), independent of gestational age. The same risk factors yielded non-significant odds ratios for the development of late-onset (vs early-onset) HDP. Women with HDP-IUGR had worse clinical outcomes. CONCLUSIONS: This study provides new information based on simple prenatal bedside examinations that might help to differentiate HDP-IUGR from HDP-AGA fetuses. These groups are associated with different fetal growth patterns and risk factors, independent of gestational age at onset of the disease. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Abdomen/diagnóstico por imagen , Peso al Nacer , Retardo del Crecimiento Fetal/diagnóstico por imagen , Hipertensión Inducida en el Embarazo/diagnóstico por imagen , Arteria Uterina/diagnóstico por imagen , Abdomen/embriología , Adulto , Femenino , Edad Gestacional , Humanos , Recién Nacido , Pruebas en el Punto de Atención , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Centros de Atención Terciaria , Ultrasonografía Doppler/métodos , Ultrasonografía Prenatal/métodos , Arteria Uterina/embriología
8.
Minerva Ginecol ; 65(6): 669-78, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24346253

RESUMEN

AIM: Perineal pain is present, after birth, in almost all (95-100%) women who have experienced perineal trauma. It has been shown that women with spontaneous vaginal delivery and minimal or absent perineal trauma will have better recoveries: less pain, more tonic perineal muscles, improved sexual function and lower rates of depression. The purpose of the present study was to prospectively assess the prevalence of perineal pain in a population of women with vaginal birth at term and physiological single newborn. METHODS: Pain assessment was performed using two subjective scales: the Verbal Numeric Scale (VNS) of 11 points and the Verbal Rating Score (VRS) of 4 points. Data collection period ran from the first postnatal day until 6 months after delivery, with two intermediate measurements at 1 and 7 weeks after birth. RESULTS: The study enrolled 451 women: 239 primiparous and 212 multiparous, with a response rate of 92% at 6 months. The prevalence of pain was found 88.2% in the first day postpartum, 62.3% one week after birth, 8.0% at seven weeks and 0.7% at six months. With regard to the resumption of sexual activity at 6 months postpartum, a dyspareunia rate of 27% was observed in the Episiotomy group (OR 5.72, P<0.001). CONCLUSION: The study found that an increase in the extent of trauma is associated with the highest scores in the self-assessment of perceived pain, with long term persistent symptoms. Furthermore, the presence of an episiotomy is a conditioning factor for the sexual function after childbirth (OR 0.43, P<0.001).


Asunto(s)
Episiotomía , Perineo , Femenino , Humanos , Periodo Posparto , Prevalencia , Estudios Prospectivos
9.
Placenta ; 32(3): 264-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21216005

RESUMEN

OBJECTIVE: To study the expression of Annexin A5 (A5) in relation to preeclampsia using immunohistochemical Tissue Microarray (TMA) technique. STUDY DESIGN: Case-control study of 66 singleton preeclamptic (PE) patients matched for gestational age (GA) at delivery with 63 normotensive controls with normally grown fetuses. Immunohistochemical expression of A5 and other population characteristics were compared between the two groups using Chi-square, One-way ANOVA, Spearman's Correlation, and Linear Regression. RESULTS: The two groups were similar for maternal age and rate of corticosteroid administration, but differed for nulliparity, Body Mass Index (BMI), blood pressure, presence of placental histological lesions, and placental weight. Expression of A5 was similar in PE and controls (p = 0.10); however it was found to be lower in PE cases complicated by fetal growth restriction (FGR, n = 34) compared with matched controls (n = 55) (p = 0.04). An inverse correlation was found between A5 and GA in cases but not in controls (p = 0.04 vs p = 0.71). The association was even more significant in the subgroup of PE complicated by FGR (p = 0.02). A5 expression was not influenced by blood pressure, proteinuria, or placental weight. CONCLUSIONS: Annexin A5 expression seems to be related only to FGR and not to PE or its clinical severity.


Asunto(s)
Anexina A5/biosíntesis , Placenta/metabolismo , Preeclampsia/metabolismo , Estudios de Casos y Controles , Femenino , Retardo del Crecimiento Fetal/metabolismo , Edad Gestacional , Humanos , Inmunohistoquímica , Embarazo , Estudios Prospectivos , Análisis de Matrices Tisulares
11.
Ultrasound Obstet Gynecol ; 36(2): 166-70, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20131337

RESUMEN

OBJECTIVE: To identify independent predictors of adverse neonatal outcome in cases of fetal growth restriction (FGR) at > or = 34 weeks. METHODS: From a cohort of 481 FGR cases delivered at > or = 34 weeks, demographic and obstetric variables, fetal biometry and Doppler indices of the uterine, umbilical and fetal middle cerebral arteries available within 2 weeks of delivery, were related to adverse neonatal outcome, defined as admission to the neonatal intensive care unit for indications other than low birth weight alone. RESULTS: Logistic regression analysis showed that gestational age (GA) at delivery (odds ratio (OR) = 0.59; 95% CI, 0.50-0.70), abdominal circumference (AC) centile (OR = 0.69; 95% CI, 0.59-0.81) and umbilical artery (UA) pulsatility index (PI) centile (OR = 1.02; 95% CI, 1.01-1.04) significantly correlated with adverse neonatal outcome. From this model we calculated a score of adverse neonatal outcome expressed by the formula: (UA-PI centile/3) - (10 x AC centile) + (10 x (40 - GA at delivery in weeks)). Receiver-operating characteristics curve analysis demonstrated that a score of > or = 25 optimally predicted adverse neonatal outcome (sensitivity of 75%, false-positive rate of 18%). Beyond 37.5 weeks, gestational age no longer had an independent impact on outcome. CONCLUSIONS: In late preterm or term FGR, GA at delivery is the most important predictor of adverse neonatal outcome. At > 37.5 weeks, delivery may be the best option to minimize adverse outcome in all FGR cases. At 34-37 weeks, a score based on GA at delivery, UA-PI centile and AC centile optimally predicts adverse neonatal outcome.


Asunto(s)
Retardo del Crecimiento Fetal/fisiopatología , Resultado del Embarazo , Arterias Umbilicales/fisiopatología , Arteria Uterina/fisiopatología , Adulto , Biometría , Velocidad del Flujo Sanguíneo/fisiología , Parto Obstétrico , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Edad Gestacional , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Cuidado Intensivo Neonatal , Flujometría por Láser-Doppler , Embarazo , Pronóstico , Ultrasonografía Prenatal , Arterias Umbilicales/diagnóstico por imagen , Arteria Uterina/diagnóstico por imagen
12.
Ultrasound Obstet Gynecol ; 34(3): 322-5, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19670350

RESUMEN

OBJECTIVES: The presence of myomas in pregnancy is associated with greater blood loss at delivery. The aim of this study was to evaluate whether the sonographic characteristics of myomas can predict blood loss at delivery in women with large myomas. METHODS: Among women who underwent second-trimester ultrasound screening at our department between January 1996 and December 2004, 251 had at least one myoma with a mean diameter > or = 5 cm. Number of myomas (single vs. multiple), maximum diameter of the largest myoma, sum of the maximum diameter of each myoma, change in size of myomas between first and last scan, and location in relation to the placenta and to the presenting part of the fetus (above or below) were analyzed in relation to blood loss at delivery and severe postpartum hemorrhage (> or = 1000 mL). RESULTS: Multivariate analysis showed that the presence of multiple myomas was the only parameter independently associated with amount of blood loss at delivery (P = 0.003). The association between the presence of multiple myomas and severe postpartum hemorrhage was of borderline significance for the statistical power of this study (P = 0.08). CONCLUSIONS: In women with large myomas, the presence of multiple tumors is independently associated with heavier blood loss at delivery but not with postpartum hemorrhage of > or = 1000 mL.


Asunto(s)
Leiomioma/diagnóstico por imagen , Hemorragia Posparto/etiología , Complicaciones Neoplásicas del Embarazo/diagnóstico por imagen , Neoplasias Uterinas/diagnóstico por imagen , Adulto , Cesárea , Femenino , Humanos , Leiomioma/complicaciones , Análisis Multivariante , Valor Predictivo de las Pruebas , Embarazo , Segundo Trimestre del Embarazo , Estudios Retrospectivos , Factores de Riesgo , Ultrasonografía , Neoplasias Uterinas/complicaciones
13.
Dig Liver Dis ; 41(9): 671-5, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19261551

RESUMEN

BACKGROUND: Intrahepatic cholestasis of pregnancy is a liver disorder with a multifactorial etiology characterized by maternal pruritus, abnormal liver function tests and increased fetal risk. The main biochemical finding is the increase in total serum bile acid concentrations. In a subgroup of women, the serum gamma-glutamyl transpeptidase level is also increased. There is evidence that dysfunction of the ABCB4 gene might play a role in intrahepatic cholestasis of pregnancy development. AIM: To investigate the role of the ABCB4 gene in Italian women with intrahepatic cholestasis of pregnancy and raised gamma-glutamyl transpeptidase by, analyzing the complete coding sequence and mRNA splicing products. METHODS: Among 299 women with intrahepatic cholestasis of pregnancy, 10 showing raised gamma-glutamyl transpeptidase were enrolled in this study. DNA and RNA were extracted from peripheral blood mononuclear cells using standard procedures. The 27 coding exons and the promoter region were amplified by polymerase chain reaction and analyzed by sequencing. Reverse transcript-polymerase chain reaction analysis of ABCB4 mRNA and cDNA analysis were also performed. RESULTS: A novel splicing mutation that causes a truncated protein of 249 amino acid was identified in a woman who had the highest serum levels of gamma-glutamyl transpeptidase, alkaline phosphatase, bile acids, and the highest pruritus score. We identified also one already described p.R590Q mutation in a woman who had significantly higher serum levels of alkaline phosphatase, aspartate, and alanine aminotransferase. CONCLUSIONS: Our study demonstrates that splicing mutations in the ABCB4 gene can cause ICP in women with high gamma-glutamyl transpeptidase and thus a complete analysis of coding sequence and cDNA products is required.


Asunto(s)
Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Colestasis Intrahepática/genética , Complicaciones del Embarazo/genética , Empalme de Proteína/genética , gamma-Glutamiltransferasa/sangre , Adulto , Ácidos y Sales Biliares/sangre , Colestasis Intrahepática/sangre , Análisis Mutacional de ADN , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/sangre , Regiones Promotoras Genéticas/genética , Prurito/etiología
14.
Opt Lett ; 34(3): 325-7, 2009 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19183646

RESUMEN

Transparent electrodes made of single-component ultrathin (<10 nm) metal films (UTMFs) are obtained by sputtering deposition. We show that the optical transparency of the deposited films (chromium and nickel) is comparable to that of indium tin oxide (ITO) in the visible and near-infrared range (0.4-2.5 microm), while it can be significantly higher in the ultraviolet (175-400 nm) and mid-infrared (2.5-25 microm) regions. Despite their very small thickness, the deposited UTMFs are also uniform and continuous over the 10 cm substrate, as it is confirmed by the measured low electrical resistivity. The excellent optical and electrical properties, stability, compatibility with active materials, process simplicity, and potential low cost make UTMFs high-quality transparent electrodes for the optoelectronics industry, seriously competing with widely used transparent conductive oxides, such as ITO.

15.
J Perinatol ; 28(2): 97-101, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18046340

RESUMEN

OBJECTIVE: To investigate the effects of transabdominal amnioinfusion (TA) on the histology of amnion (A) and umbilical cord (UC). STUDY DESIGN: From a cohort of 56 singleton pregnancies with premature rupture of membranes (PROM) at

Asunto(s)
Amnios/patología , Cloruro de Sodio/administración & dosificación , Cordón Umbilical/patología , Adulto , Líquido Amniótico , Corion/patología , Células Epiteliales , Femenino , Rotura Prematura de Membranas Fetales , Humanos , Oligohidramnios/patología , Oligohidramnios/terapia , Circulación Placentaria/fisiología , Embarazo , Resultado del Embarazo , Segundo Trimestre del Embarazo
16.
Opt Express ; 15(17): 10739-43, 2007 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-19547429

RESUMEN

Domain inversion is used in a simple fashion to improve significantly the performance of a waveguide electro-optic modulator in z-cut LiNbO(3). The waveguide arms of the Mach-Zehnder interferometer are placed in opposite domain-oriented regions under the same, narrower and more efficient electrode, so that opposite phase shifts (push-pull effect) can still be achieved despite the arms being subjected to the same electric field. Switching voltages close to 2 V are obtained, which allow 10Gb/s modulation with inexpensive drivers, such as those used for electro-absorption modulators, which deliver driving voltages well below 3V.

17.
Br J Clin Pharmacol ; 61(3): 336-40, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16487228

RESUMEN

AIMS: Toxoplasma infection in pregnancy is usually treated with long-term administration of the macrolide spiramycin to prevent fetal malformations. We had empirically observed that treated patients seldom developed pregnancy-induced hypertension (PIH), a common and severe disorder of pregnancy whose aetiology and pathogenesis are still debated. Some clinical and experimental data suggest that infection could play a role in its development. METHODS: To test this hypothesis, we studied a cohort of 417 pregnant women treated with spiramycin because of seroconversion for Toxoplasma gondii and 353 low-risk women who did not take any antibiotic during pregnancy. PIH was defined as blood pressure>140/90 mmHg on two or more occasions, occurring after 20 weeks of gestational age. RESULTS: Seventeen (5.2%) women in the control group developed PIH compared with two (0.5%) in the case group. The odds of developing the disease were significantly lower in the treated subjects (odds ratio=0.092, 95% confidence interval 0.021, 0.399; P<0.001). CONCLUSIONS: Our results suggest that antibiotic treatment during pregnancy can reduce the incidence of PIH, thus opening new perspectives in its prevention and therapy.


Asunto(s)
Antibacterianos/uso terapéutico , Hipertensión Inducida en el Embarazo/prevención & control , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Espiramicina/uso terapéutico , Toxoplasmosis/tratamiento farmacológico , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Preeclampsia/prevención & control , Embarazo
18.
Biochem Soc Trans ; 33(Pt 5): 1003-7, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16246032

RESUMEN

Unique among ABC (ATP-binding cassette) protein family members, CFTR (cystic fibrosis transmembrane conductance regulator), also termed ABCC7, encoded by the gene mutated in cystic fibrosis patients, functions as an ion channel. Opening and closing of its anion-selective pore are linked to ATP binding and hydrolysis at CFTR's two NBDs (nucleotide-binding domains), NBD1 and NBD2. Isolated NBDs of prokaryotic ABC proteins form homodimers upon binding ATP, but separate after hydrolysis of the ATP. By combining mutagenesis with single-channel recording and nucleotide photolabelling on intact CFTR molecules, we relate opening and closing of the channel gates to ATP-mediated events in the NBDs. In particular, we demonstrate that two CFTR residues, predicted to lie on opposite sides of its anticipated NBD1-NBD2 heterodimer interface, are energetically coupled when the channels open but are independent of each other in closed channels. This directly links ATP-driven tight dimerization of CFTR's cytoplasmic NBDs to opening of the ion channel in the transmembrane domains. Evolutionary conservation of the energetically coupled residues in a manner that preserves their ability to form a hydrogen bond argues that this molecular mechanism, involving dynamic restructuring of the NBD dimer interface, is shared by all members of the ABC protein superfamily.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/fisiología , Activación del Canal Iónico/fisiología , Transportadoras de Casetes de Unión a ATP/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Regulador de Conductancia de Transmembrana de Fibrosis Quística/química , Humanos , Mutagénesis , Nucleótidos/metabolismo
20.
BJOG ; 108(3): 325-6, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11281476

RESUMEN

We evaluated the efficacy and safety of nimesulide (100 mg orally twice daily for > 48 hours) in a pilot series of five women (two with twin pregnancies) at 24(+6) weeks (range 21(+3) - 27(+2)) in preterm labour which was unresponsive to intravenous ritodrine. Nimesulide therapy was continued for eight days (5-16) and was associated with a prolongation of pregnancy of 27 days (6-69). Oligohydramnios occurred in all seven fetuses after three to nine days of therapy, and in the five pregnancies that continued after discontinuation of nimesulide, it resolved within four days (2-7). None of the babies manifested permanent renal damage.


Asunto(s)
Inhibidores de la Ciclooxigenasa/efectos adversos , Trabajo de Parto Prematuro/prevención & control , Oligohidramnios/inducido químicamente , Sulfonamidas/efectos adversos , Tocolíticos/efectos adversos , Administración Oral , Adulto , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Femenino , Humanos , Indometacina/efectos adversos , Isoenzimas/antagonistas & inhibidores , Proteínas de la Membrana , Proyectos Piloto , Embarazo , Prostaglandina-Endoperóxido Sintasas , Sulfonamidas/administración & dosificación , Tocolíticos/administración & dosificación , Resultado del Tratamiento
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