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1.
Proc Natl Acad Sci U S A ; 121(16): e2314885121, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38588413

RESUMEN

As a result of partial hepatectomy, the remaining liver tissue undergoes a process of renewed proliferation that leads to rapid regeneration of the liver. By following the early stages of this process, we observed dramatic programmed changes in the DNA methylation profile, characterized by both de novo and demethylation events, with a subsequent return to the original adult pattern as the liver matures. Strikingly, these transient alterations partially mimic the DNA methylation state of embryonic hepatoblasts (E16.5), indicating that hepatocytes actually undergo epigenetic dedifferentiation. Furthermore, Tet2/Tet3-deletion experiments demonstrated that these changes in methylation are necessary for carrying out basic embryonic functions, such as proliferation, a key step in liver regeneration. This implies that unlike tissue-specific regulatory regions that remain demethylated in the adult, early embryonic genes are programmed to first undergo demethylation, followed by remethylation as development proceeds. The identification of this built-in system may open targeting opportunities for regenerative medicine.


Asunto(s)
Metilación de ADN , Embrión de Mamíferos , Embrión de Mamíferos/metabolismo , Hepatocitos
2.
Proc Natl Acad Sci U S A ; 119(52): e2212306119, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36534800

RESUMEN

Injury to muscle brings about the activation of stem cells, which then generate new myocytes to replace damaged tissue. We demonstrate that this activation is accompanied by a dramatic change in the stem-cell methylation pattern that prepares them epigenetically for terminal myocyte differentiation. These de- and de novo methylation events occur at regulatory elements associated with genes involved in myogenesis and are necessary for activation and regeneration. Local injury of one muscle elicits an almost identical epigenetic change in satellite cells from other muscles in the body, in a process mediated by circulating factors. Furthermore, this same methylation state is also generated in muscle stem cells (MuSCs) of female animals following pregnancy, even in the absence of any injury. Unlike the activation-induced expression changes, which are transient, the induced methylation profile is stably maintained in resident MuSCs and thus represents a molecular memory of previous physiological events that is probably programmed to provide a mechanism for long-term adaptation.


Asunto(s)
Metilación de ADN , Músculo Esquelético , Animales , Femenino , Músculo Esquelético/metabolismo , Células Madre/metabolismo , Diferenciación Celular/genética , Epigénesis Genética , Desarrollo de Músculos/genética , Regeneración/genética
3.
Eur J Pediatr ; 183(2): 697-705, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37975943

RESUMEN

To evaluate the effectiveness of a novel protocol, adopted in our institution, as a quality improvement project for congenital diaphragmatic hernia (CDH). A maximal lung protection (MLP) protocol was implemented in 2019. This strategy included immediate use of high-frequency oscillatory ventilation (HFOV) after birth, during the stay at the Neonatal Intensive Care Unit (NICU), and during surgical repair. HFOV strategy included low distending pressures and higher frequencies (15 Hz) with subsequent lower tidal volumes. Surgical repair was performed early, within 24 h of birth, if possible. A retrospective study of all inborn neonates prenatally diagnosed with CDH and without major associated anomalies was performed at the NICU of Schneider Children's Medical Center of Israel between 2009 and 2022. Survival rates and pulmonary outcomes of neonates managed with MLP were compared to the historical standard care cohort. Thirty-three neonates were managed with the MLP protocol vs. 39 neonates that were not. Major adverse outcomes decreased including death rate from 46 to 18% (p = 0.012), extracorporeal membrane oxygenation from 39 to 0% (p < 0.001), and pneumothorax from 18 to 0% (p = 0.013). CONCLUSION:  MLP with early surgery significantly improved survival and additional adverse outcomes of neonates with CDH. Prospective randomized studies are necessary to confirm the findings of the current study. WHAT IS KNOWN: • Ventilator-induced lung injury was reported as the main cause of mortality in neonates with congenital diaphragmatic hernia (CDH). • Conventional ventilation is recommended by the European CDH consortium as the first-line ventilation modality; timing of surgery is controversial. WHAT IS NEW: • A maximal lung protection strategy based on 15-Hz high-frequency oscillatory ventilation with low distending pressures as initial modality and early surgery significantly reduced mortality and other outcomes.


Asunto(s)
Hernias Diafragmáticas Congénitas , Humanos , Recién Nacido , Hernias Diafragmáticas Congénitas/cirugía , Pulmón , Estudios Prospectivos , Mejoramiento de la Calidad , Estudios Retrospectivos , Tasa de Supervivencia
4.
Arch Gynecol Obstet ; 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37789206

RESUMEN

PURPOSE: To provide a comprehensive report of the experience gained in the prenatal treatment of congenital diaphragmatic hernia (CDH) using fetoscopic endoluminal tracheal occlusion (FETO) following its implementation at a newly established specialized fetal medicine center. METHODS: Mothers of fetuses with severe CDH were offered prenatal treatment by FETO. RESULTS: Between 2018 and 2021, 16 cases of severe CDH underwent FETO. The median gestational age (GA) at balloon insertion was 28.4 weeks (IQR 27.8-28.6). The median GA at delivery was 37 weeks (IQR 34.4-37.8). The survival rate was 8/16 cases (50%). None of the survivors required home oxygen therapy at 6 months of age. Comparison between the survivors and deceased showed that survivors had balloon insertion 1 week earlier (27.8 vs. 28.4 weeks, p = 0.007), a higher amniotic fluid level change between pre- to post-FETO (3.4 vs 1.3, p = 0.024), a higher O/E LHR change between pre- to post-FETO (50.8 vs. 37.5, p = 0.047), and a GA at delivery that was 2 weeks later (37.6 vs. 35.4 weeks, p = 0.032). CONCLUSIONS: The survival rate at 6 months of age in cases of severe CDH treated with FETO in our center was 50%. Our new fetal medicine center matches the performance of other leading international centers.

5.
Am J Obstet Gynecol ; 225(6): 678.e1-678.e11, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34089698

RESUMEN

BACKGROUND: The multicenter randomized controlled trial Management of Myelomeningocele Study demonstrated that prenatal repair of open spina bifida by hysterotomy, compared with postnatal repair, decreases the need for ventriculoperitoneal shunting and increases the chances of independent ambulation. However, the hysterotomy approach is associated with risks that are inherent to the uterine incision. Fetal surgeons from around the world embarked on fetoscopic open spina bifida repair aiming to reduce maternal and fetal/neonatal risks while preserving the neurologic benefits of in utero surgery to the child. OBJECTIVE: This study aimed to report the main obstetrical, perinatal, and neurosurgical outcomes in the first 12 months of life of children undergoing prenatal fetoscopic repair of open spina bifida included in an international registry and to compare these with the results reported in the Management of Myelomeningocele Study and in a subsequent large cohort of patients who received an open fetal surgery repair. STUDY DESIGN: All known centers performing fetoscopic spina bifida repair were contacted and invited to participate in a Fetoscopic Myelomeningocele Repair Consortium and enroll their patients in a registry. Patient data entered into this fetoscopic registry were analyzed for this report. Fisher exact test was performed for comparison of categorical variables in the registry with both the Management of Myelomeningocele Study and a post-Management of Myelomeningocele Study cohort. Binary logistic regression analyses were used to assess the registry data for predictors of preterm birth at <30 weeks' gestation, preterm premature rupture of membranes, and need for postnatal cerebrospinal fluid diversion in the fetoscopic registry. RESULTS: There were 300 patients in the fetoscopic registry, 78 in the Management of Myelomeningocele Study, and 100 in the post-Management of Myelomeningocele Study cohort. The 3 data sets showed similar anatomic levels of the spinal lesion, mean gestational age at delivery, distribution of motor function compared with upper anatomic level of the lesion in the neonates, and perinatal death. In the Management of Myelomeningocele Study (26.16±1.6 weeks) and post-Management of Myelomeningocele Study cohort (23.3 [20.2-25.6] weeks), compared with the fetoscopic registry group (23.6±1.4 weeks), the gestational age at surgery was lower (comparing fetoscopic repair group with the Management of Myelomeningocele Study; P<.01). After open fetal surgery, all patients were delivered by cesarean delivery, whereas in the fetoscopic registry approximately one-third were delivered vaginally (P<.01). At cesarean delivery, areas of dehiscence or thinning in the scar were observed in 34% of cases in the Management of Myelomeningocele Study, in 49% in the post-Management of Myelomeningocele Study cohort, and in 0% in the fetoscopic registry (P<.01 for both comparisons). At 12 months of age, there was no significant difference in the number of patients requiring treatment for hydrocephalus between those in the fetoscopic registry and the Management of Myelomeningocele Study. CONCLUSION: Prenatal and postnatal outcomes up to 12 months of age after prenatal fetoscopic and open fetal surgery repair of open spina bifida are similar. Fetoscopic repair allows for having a vaginal delivery and eliminates the risk of uterine scar dehiscence, therefore protecting subsequent pregnancies of unnecessary maternal and fetal risks.


Asunto(s)
Atención Prenatal , Espina Bífida Quística/cirugía , Adolescente , Adulto , Femenino , Fetoscopía , Salud Global , Humanos , Histerotomía , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Guías de Práctica Clínica como Asunto , Embarazo , Sociedades Médicas , Adulto Joven
6.
Pediatr Dev Pathol ; 24(4): 383-387, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33749381

RESUMEN

Fetal urinoma is defined as an encapsulated accumulation of extravasated urine within the perirenal space or retroperitoneum. It is an uncommon finding in prenatal practice, and the vast majority of known cases are strongly associated with the existence of a urinary obstruction, such as posterior urethral valves, ureteropelvic junction obstruction, or ureterocele. We report a unique case of prenatally detected fetal bladder urinoma that occurred in the absence of an apparent obstructive uropathy, but was associated with extensive ischemic necrosis and calcifications of adjacent bladder wall, coexistent with signs of vascular supply decompensation.


Asunto(s)
Ascitis/patología , Enfermedades Fetales/patología , Arterias Umbilicales/anomalías , Vejiga Urinaria/irrigación sanguínea , Vejiga Urinaria/patología , Urinoma/patología , Aborto Eugénico , Adulto , Ascitis/diagnóstico por imagen , Femenino , Enfermedades Fetales/diagnóstico por imagen , Humanos , Isquemia , Masculino , Necrosis , Embarazo , Ultrasonografía Prenatal , Arterias Umbilicales/diagnóstico por imagen , Arterias Umbilicales/patología , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/embriología , Urinoma/diagnóstico por imagen , Urinoma/embriología
7.
Prenat Diagn ; 39(11): 1005-1010, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31330572

RESUMEN

Gestational age determination by traditional tools (last menstrual period, ultrasonography measurements and Ballard Maturational Assessment in newborns) has major limitations and therefore there is a need to find different approaches. In this study, we looked for a molecular marker that can be used to determine the accurate gestational age of the newborn. To this end, we performed reduced representation bisulfite sequencing (RRBS) on 41 cord blood and matching placenta samples from women between 25 and 40 weeks of gestation and generated an epigenetic clock based on the methylation level at different loci in the genome. We identified a set of 332 differentially methylated regions (DMRs) that undergo demethylation in late gestational age in cord blood cells and can predict the gestational age (r = -.7, P = 2E-05). Once the set of 411 DMRs that undergo de novo methylation in late gestational age was used in combination with the first set, it generated a more accurate clock (R = .77, P = 1.87E-05). We have compared gestational age determined by Ballard score assessment with our epigenetic clock and found high concordance. Taken together, this study demonstrates that DNA methylation can accurately predict gestational age and thus may serve as a good clinical predictor.


Asunto(s)
Metilación de ADN , Edad Gestacional , Biomarcadores , Femenino , Genoma Humano , Humanos , Embarazo
8.
Arch Gynecol Obstet ; 297(5): 1293-1299, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29435657

RESUMEN

PURPOSE: The aim of this study was to evaluate the risk of preeclampsia in women of advanced age who conceived through donated oocytes as compared with natural conceptions. METHODS: A historical prospective study of singleton live births of parturients ≥ 45 years of age at four university hospitals was conducted. For the purpose of the study, the population was divided by the mode of conception into two groups: oocyte donation and natural conception. The main outcome variable in this study was preeclampsia. Secondary outcomes included pregnancy-induced hypertension and Small for Gestational Age. RESULTS: Two hundred and seventy pregnancies were achieved naturally and 135 women conceived by oocyte donation. Mean age at delivery for the natural conception and oocyte donation groups was 45.7 and 47.8, respectively. Preeclampsia complicated 3 out of 270 (1.1%) natural conception pregnancies and 17 out of 135 (12.6%) oocyte donation conceptions. After adjusting for confounders, oocyte donation pregnancies were found to be associated with a 12-fold increased risk for preeclampsia (P = 0.001). Among oocyte donation pregnancies, the risk of preeclampsia was not affected by parity or age. CONCLUSIONS: A substantially increased risk for preeclampsia was found in oocyte donation pregnancies, suggesting that the foreign oocyte may play a specific biologic role in the development of preeclampsia after the age of 45.


Asunto(s)
Fertilización In Vitro/efectos adversos , Edad Materna , Donación de Oocito/efectos adversos , Preeclampsia/epidemiología , Adulto , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Madres , Preeclampsia/etiología , Embarazo , Estudios Prospectivos , Estudios Retrospectivos
9.
Genes Dev ; 24(6): 543-8, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20231314

RESUMEN

Regenerative capacity is progressively lost with age. Here we show that pregnancy markedly improved liver regeneration in aged mice concomitantly with inducing a switch from proliferation-based liver regeneration to a regenerative process mediated by cell growth. We found that the key mediator of this switch was the Akt/mTORC1 pathway; its inhibition blocked hypertrophy, while increasing proliferation. Moreover, pharmacological activation of this pathway sufficed to induce the hypertrophy module, mimicking pregnancy. This treatment dramatically improved hepatic regenerative capacity and survival of old mice. Thus, cell growth-mediated mass reconstitution, which is relatively resistant to the detrimental effects of aging, is employed in a physiological situation and holds potential as a therapeutic strategy for ameliorating age-related functional deterioration.


Asunto(s)
Envejecimiento/fisiología , Regeneración Hepática/fisiología , Hígado/metabolismo , Factores de Transcripción/metabolismo , Animales , Antibióticos Antineoplásicos/farmacología , Proliferación Celular , Femenino , Hepatectomía , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Hiperplasia/metabolismo , Hipertrofia/metabolismo , Hígado/citología , Hígado/efectos de los fármacos , Hígado/crecimiento & desarrollo , Hígado/cirugía , Regeneración Hepática/efectos de los fármacos , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Ratones Endogámicos C57BL , Complejos Multiproteicos , Embarazo , Proteínas , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Serina-Treonina Quinasas TOR
10.
Harefuah ; 157(3): 170-174, 2018 Mar.
Artículo en Hebreo | MEDLINE | ID: mdl-29582948

RESUMEN

INTRODUCTION: : Minimally invasive fetal therapeutic procedures reduce the morbidity and mortality in monochorionic (MC) twins and in fetuses with congenital diaphragmatic hernia (CDH). MC pregnancies share their blood systems due to communicating vessels over their single placenta and may develop specific complications: Twin-to-Twin transfusion syndrome (TTTS), Selective intrauterine growth restriction (sIUGR), Twin Anemia-Polycythemia Sequence (TAPS), Twin Reverse Arterial Perfusion Syndrome (TRAP) or anomalies in one. Half of complicated MC require intrauterine interventions. Severe CDH is linked to a high rate of neonatal death due to pulmonary hypoplasia. Fetoscopic tracheal occlusion (FETO) with a balloon improves postnatal outcome. AIMS: A fetal therapy center was established in the Hadassah Medical Centers, Jerusalem in 2011 for intrauterine interventions. We report our 5 years' experience. METHODS: This prospective cohort follows the outcome of MC pregnancies and cases of severe CDH which underwent therapeutic fetal procedures in Hadassah between the years 2011-16. RESULTS: Out of 114 procedures, 95 were in MC: 84 monochorionic diamniotic twins, 7 monochorionic monoamniotic twins, 2 dichorionic triamniotic triplets and 2 monochorionic triplets. We treated 65 TTTS cases with fetoscopy and laser ablation of communicating vessels. The survival rate of both twins was 58.5% and at least one survived in 81.5% of the cases. In 2nd/3rd trimesters selective termination of 15 cases the survival rate of the remaining twin was 87%. In 11 cases of TRAP sequence treated with laser ablation of the feeding vessel the survival of the remaining twin was 91%. In 19 fetoscopies in severe CDH, 12 were for balloon insertion and 7 for removal. Endotracheal balloon was successfully placed in 11 of 12 cases (10 left-sided, 1 right-sided CDH). Balloon removal was prenatally performed by elective fetoscopy (n=7) or by intrapartum urgent puncture. There were no intrauterine fetal deaths. In isolated left-sided CDH the survival was 57%, whereas none survived in non-isolated left-sided CDH and right sided CDH. CONCLUSIONS: In-utero procedures are safe for the mother and increase newborn survival in MC pregnancies, thus specialized clinics are life-saving. FETO is a therapeutic option for severe CDH. Our results meet similar achievements reported by other leading world centers.


Asunto(s)
Transfusión Feto-Fetal/cirugía , Hernias Diafragmáticas Congénitas/terapia , Placenta/irrigación sanguínea , Oclusión con Balón/métodos , Femenino , Enfermedades Fetales/cirugía , Enfermedades Fetales/terapia , Fetoscopía/métodos , Hernias Diafragmáticas Congénitas/cirugía , Humanos , Recién Nacido , Terapia por Láser , Enfermedades Placentarias/cirugía , Embarazo , Estudios Prospectivos
11.
Prenat Diagn ; 31(1): 28-32, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21190270

RESUMEN

OBJECTIVES: To compare liver volume between trisomy 21 and euploid fetuses at 11 to 13 weeks' gestation. METHODS: Fetal liver volume was measured by 3D ultrasound in fetuses at low risk of aneuploidies (n = 200) and another group at high risk, including 148 euploid and 37 with trisomy 21. The association of liver volume with fetal nuchal translucency (NT) thickness, tricuspid regurgitation and reversed a-wave in the ductus venosus was investigated. RESULTS: In the low-risk group, fetal liver volume increased exponentially with fetal crown-rump length (CRL) from a median of 0.5 cm(3) at CRL of 45 mm to about 2.5 cm(3) at CRL of 84 mm. In 27 (73.0%) of the trisomy 21 fetuses liver volume was above the 95th percentile of the low-risk group, whereas in the euploid fetuses liver volume was not significantly altered (P = 0.521). There were no significant contributions to liver volume from fetal NT (P = 0.508), tricuspid regurgitation (P = 0.958) or reversed a-wave in the ductus venosus (P = 0.872). CONCLUSION: In trisomy 21 fetuses at 11 to 13 weeks liver volume is increased.


Asunto(s)
Síndrome de Down/diagnóstico por imagen , Edad Gestacional , Hígado/diagnóstico por imagen , Hígado/embriología , Adulto , Largo Cráneo-Cadera , Femenino , Corazón Fetal/diagnóstico por imagen , Humanos , Medida de Translucencia Nucal , Embarazo , Estudios Retrospectivos , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen , Insuficiencia de la Válvula Tricúspide/embriología , Ultrasonografía Prenatal
12.
Prenat Diagn ; 31(1): 22-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21210477

RESUMEN

OBJECTIVE: To determine possible differences in hepatic artery flow between trisomy 21 and euploid fetuses at 11-13 weeks' gestation. METHODS: Hepatic artery pulsatility index (PI) and peak systolic velocity (PSV) were measured in fetuses at low risk of aneuploidies (n = 350) and another group at high risk, including 283 euploid and 47 with trisomy 21. The association of hepatic artery PI and PSV with trisomy 21, fetal nuchal translucency (NT) thickness, tricuspid regurgitation, and reversed a-wave in the ductus venosus was investigated. RESULTS: In the low-risk group, the median hepatic artery PSV was 10.0 cm/s and the 95th centile was 14.3 cm/s. The distribution of hepatic artery PI was skewed, but for PI of 2 or more the distribution was Gaussian. In 325 (92.9%) cases, the PI was 2 or more (high PI) and in 25 (7.1%) it was below 2 (low PI). In 33 (70.2%) of the trisomy 21 pregnancies, the PSV was above the 95th centile and the PI was below 2. Multiple regression analysis showed that in the prediction of hepatic artery PSV there were significant contributions from fetal karyotype, tricuspid regurgitation, and reversed a-wave in the ductus venosus, but not delta NT, pregnancy-associated plasma protein-A, or free ß-human chorionic gonadotrophin. CONCLUSION: Trisomy 21 at 11-13 weeks is associated with increased flow in the hepatic artery.


Asunto(s)
Síndrome de Down/diagnóstico por imagen , Edad Gestacional , Arteria Hepática/diagnóstico por imagen , Arteria Hepática/embriología , Ultrasonografía Prenatal , Adulto , Velocidad del Flujo Sanguíneo , Femenino , Humanos , Medida de Translucencia Nucal , Embarazo , Estudios Prospectivos , Flujo Pulsátil
13.
Prenat Diagn ; 31(8): 773-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21692085

RESUMEN

OBJECTIVES: To establish a normal range for fetal adrenal gland length at 11-13 weeks' gestation and to investigate whether the length is altered in fetal trisomy 18. METHODS: Fetal adrenal gland length was measured by three-dimensional ultrasound in fetuses at low risk of aneuploidies (n = 400) and another group at high risk, including 380 euploid fetuses and 41 with trisomy 18. The data of the low-risk group were used to establish a reference range of adrenal gland length with crown-rump length (CRL). In the high-risk group, adrenal gland length in the euploid and trisomy 18 groups was compared. RESULTS: In the low-risk group, fetal adrenal gland size increased exponentially with fetal CRL from a median of 2.3 mm at CRL of 45 mm to about 4.4 cm at CRL of 84 mm. In trisomy 18, the median adrenal gland length for CRL was significantly lower than the median in the low-risk group (-1.37 mm; interquartile range: - 1.67 to - 0.99 mm, p < 0.0001). In euploid fetuses, the adrenal gland size was not significantly from the low-risk group (p = 0.100). CONCLUSION: Trisomy 18 is associated with adrenal gland hypoplasia which is apparent at 11-13 weeks' gestation.


Asunto(s)
Glándulas Suprarrenales/patología , Cromosomas Humanos Par 18 , Trisomía/patología , Glándulas Suprarrenales/diagnóstico por imagen , Adulto , Femenino , Feto/patología , Humanos , Imagenología Tridimensional , Embarazo , Primer Trimestre del Embarazo , Valores de Referencia , Ultrasonografía Prenatal
14.
Placenta ; 90: 52-57, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-32056552

RESUMEN

INTRODUCTION: We previously reported blood oxygen level dependent MRI (BOLD-MRI) for monitoring placental and fetal hemodynamic changes in mice following maternal hypercapnia. Here we use BOLD-MRI to compare the placental and fetal hemodynamic effects of different maternal vasopressors in mice. METHODS: Pregnant ICR mice (n = 16; E17.5) anesthetized with pentobarbital (80 mg/kg i.p.) were placed supine in a 4.7-T Bruker Biospec MRI. Following baseline images, equipotential doses of ephedrine (10 mg/kg) or phenylephrine (10mcg/kg) were administered intravenously. Changes in placental and fetal signal were analyzed from T2*-weighted gradient echo MR images (TR/TE = 147/10 ms). Different regions of interest (placenta, fetal heart, fetal liver and fetal brain) were identified. Percentage change of BOLD-MRI signal intensity (SI) were presented as time curves. RESULTS: Ephedrine and phenylephrine elicited markedly different effects. Phenylephrine caused an approximate 50% reduction in placental, fetal heart and fetal liver BOLD-MRI-SI, but fetal brain BOLD-MRI-SI was unchanged (statistically different from placenta and other fetal organs; p < 0.001), and the fetal brain/liver BOLD-MRI-SI ratio was markedly increased versus baseline (p < 0.001). Following ephedrine, placental BOLD-MRI-SI increased 30% and fetal heart BOLD-MRI-SI was reduced 26%; other fetal organs were unchanged. Blood gases were unchanged. DISCUSSION: Phenylephrine induced BOLD-MRI-SI changes suggestive of placental and fetal hypoperfusion with brain sparing. Ephedrine induced BOLD-MRI-SI changes suggestive of increased cardiac output; we speculate that reduced fetal heart BOLD-MRI-SI may be due to increased fetal myocardial oxygen extraction or metabolic acidosis. The result demonstrates the potential of BOLD-MRI as a non-invasive hemodynamic tool for assessing pharmacodynamics effects in the placental and fetus.


Asunto(s)
Encéfalo/efectos de los fármacos , Efedrina/farmacología , Feto/efectos de los fármacos , Fenilefrina/farmacología , Placenta/efectos de los fármacos , Vasoconstrictores/farmacología , Animales , Encéfalo/diagnóstico por imagen , Femenino , Feto/diagnóstico por imagen , Hemodinámica/efectos de los fármacos , Imagen por Resonancia Magnética , Ratones , Placenta/diagnóstico por imagen , Embarazo
15.
Reprod Biomed Online ; 19(6): 888-98, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20031033

RESUMEN

The objective of the current report was to provide a summary of knowledge concerning the treatment of women with poor ovarian response with androgens and androgen modulating agents. This involved a review of the literature. The literature search was performed using PubMed. Information concerning the role of androgens and androgen modulating agents in treating women with poor ovarian response is limited. The search of the literature yielded five studies and one case report concerning the treatment of poor responders with androgens. The variations in patient selection, type of androgens employed and the different duration of exposure preclude drawing any definite conclusions. Aromatase inhibitors block the conversion of androgens to oestrogens, thereby promoting an androgen-rich intrafollicular environment. The evidence presented in this review suggests a potential beneficial role for the use of aromatase inhibitors in treating women who have previously experienced failure of standard IVF protocols. The optimal dose and duration of this treatment is yet to be determined. Although the results of studies concerning LH supplementation in poor responders are conflicting, the latest Cochrane review on the use of recombinant LH for ovarian stimulation supports its use in poor responders, based on pooled pregnancy estimates.


Asunto(s)
Andrógenos/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Inducción de la Ovulación/métodos , Andrógenos/biosíntesis , Animales , Ensayos Clínicos como Asunto , Femenino , Fármacos para la Fertilidad Femenina/uso terapéutico , Fertilización In Vitro/métodos , Humanos , Hormona Luteinizante/fisiología , Embarazo
16.
Placenta ; 63: 53-60, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29061514

RESUMEN

INTRODUCTION: We evaluated changes in placental and fetal hemodynamics in rodents during acute hypercapnia using BOLD-MRI and Doppler ultrasound. METHODS: Animals were anesthetized with pentobarbital and, in consecutive 4-min periods, breathed: air, 21%O2:5%CO2, and 95%O2:5%CO2. BOLD-MRI: Pregnant ICR mice (n = 6; E17.5) were scanned in a 4.7-T Bruker Biospec spectrometer. Placenta and fetal liver, heart and brain were identified on True-FISP images. Percent change in signal intensity (SI) were analyzed every 30 s from T2*-weighted GE images (TR/TE = 147/10 ms). Doppler: Pregnant Wistar rats (n = 6; E18-20) were anesthetized with pentobarbital and received abdominal Doppler ultrasound. Umbilical artery pulsatility index (PI) and fetal heart rate were assessed at baseline and after two minutes of both hypercapnic challenges. RESULTS: BOLD-MRI: Normoxic-hypercapnia caused immediate marked reduction in SI in placenta (-44% ± 5.5; p < 0.001), fetal liver (-32% ± 6.4; p < 0.001) and fetal heart (-53% ± 9.9; p < 0.001) but only minor changes in fetal brain (-13% ± 3.4; p < 0.01), suggesting fetal brain sparing. Doppler: Normoxic-hypercapnia caused a marked increase in umbilical artery PI (+27.4% ± 7.2; p < 0.001) and a reduction in fetal heart rate (-48 bpm; 95%CI -9.3 to -87.0; p = 0.02), suggesting acute fetal asphyxia. CONCLUSIONS: Brief maternal hypercapnic challenge caused BOLD-MRI changes consistent with acute placental and fetal hypoperfusion with fetal brain sparing. The same challenge caused increased umbilical artery PI and fetal bradycardia on Doppler ultrasound, suggestive for acute fetal asphyxia. BOLD-MRI may be a suitable noninvasive imaging strategy to assess placental and fetal organ hemodynamics.


Asunto(s)
Encéfalo/diagnóstico por imagen , Hipercapnia/diagnóstico por imagen , Placenta/irrigación sanguínea , Animales , Velocidad del Flujo Sanguíneo/fisiología , Femenino , Imagen por Resonancia Magnética/métodos , Placenta/diagnóstico por imagen , Embarazo , Ratas , Ratas Wistar , Ultrasonografía Doppler , Arterias Umbilicales/diagnóstico por imagen
17.
Harefuah ; 144(12): 859-64, 910, 2005 Dec.
Artículo en Hebreo | MEDLINE | ID: mdl-16400787

RESUMEN

BACKGROUND: Thromboembolic events are quite common in obstetrics and gynecology and constitute a significant cause for morbidity and mortality. Recently, a decline in complication rates has been observed following the implementation of effective preventive measures. OBJECTIVE: This article aims to review the different prevention and treatment methods and to evaluate their efficiency. Furthermore, the article strives to forge a structured approach and form appropriate protocols for our population. RESULTS: Many studies have shown that the extensive use of preventive treatment is safe, clinically effective and valuable from the cost-benefit perspective. Nevertheless, most surveys performed around the world showed that the number of surgeons that use prophylactic treatment is lower than expected. In our department, we have engaged in a discussion with our hematologist and created protocols with simple and clear flow-charts for DVT and PE prevention, both in gynecological operations and in obstetrics. CONCLUSION: The implementation of a clear departmental policy will increase the awareness and the use of preventive treatment and will potentially decrease morbidity and mortality from thromboembolic events.


Asunto(s)
Complicaciones Cardiovasculares del Embarazo/prevención & control , Tromboembolia/prevención & control , Femenino , Humanos , Embarazo , Complicaciones Cardiovasculares del Embarazo/epidemiología , Tromboembolia/epidemiología , Venas
18.
Fertil Steril ; 103(5): 1125-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25813291

RESUMEN

Aging is associated with reduced tissue regenerative capacity. In recent years, studies in mice have shown that transfusion of blood from young animals to old ones can reverse some aging effects and increase regenerative potential similar to that seen in young animals. Because pregnancy is a unique biological model of a partially shared blood system, we have speculated that pregnancy would have a rejuvenating effect on the mother. Recent studies support this idea. In this review, we will summarize the current knowledge of the rejuvenating effect of pregnancy on the mother.


Asunto(s)
Envejecimiento/fisiología , Regeneración , Adulto , Animales , Proliferación Celular , Sistema Nervioso Central/fisiología , Quimerismo , Femenino , Estado de Salud , Corazón/fisiología , Humanos , Regeneración Hepática , Longevidad , Edad Materna , Bienestar Materno , Regeneración Nerviosa , Embarazo
19.
Ann Epidemiol ; 25(6): 387-91, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25976022

RESUMEN

PURPOSE: To examine the association between the mother's age at last birth and maternal long-term survival. METHODS: Data from three national censuses (1972, 1983, and 1995) and national birth and death records (1972-2009) were used to examine the association between age at last birth and mortality while accounting for potential confounders, such as parity. Age-adjusted mortality rates and Cox proportional hazard models were used in the analysis. RESULTS: A total of 887 women who delivered their last child after 45 years of age were identified from among 178,507 women (1,592,379 person-years). Age-adjusted mortality rates from 55 years of age were highest for childless women (9.2 per 1000) and decreased linearly (P < .001) for parous women with increased age at last birth (5.2 per 1000 for women aged ≥45 years at last birth). In models adjusted for age at first birth and parity, mortality risks were lowest among parous women with late-age births (≥45 years) compared with parous women with their last births before 35 years of age (hazard ratio, 0.58; 95% confidence interval, 0.40-0.86). CONCLUSIONS: This study provides new empirical evidence that late-age births are associated with maternal longevity, although a direct causal relation cannot be established with the information available.


Asunto(s)
Longevidad , Edad Materna , Adulto , Censos , Femenino , Humanos , Israel , Persona de Mediana Edad , Mortalidad , Paridad , Embarazo , Modelos de Riesgos Proporcionales
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