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1.
Acta Oncol ; 58(12): 1740-1744, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31526171

RESUMEN

Background: The SIOPE-Brain Tumor Group recently published a guideline on craniospinal target volume delineation for highly conformal radiotherapy. In order to spare critical structures like e.g., the lens or cochlea, highly conformal techniques can underdose the cerebrospinal fluid (CSF) in the dural reflections around cranial and sacral nerves. The purpose of this study is to generate evidence for CSF extension within the dural sheaths of the cranial and sacral nerves in order to improve accuracy in target volume delineation.Material and methods: Ten healthy volunteers, age 21 till 41 years, underwent an MRI-scan of the skull-base and sacral plexus. To evaluate CSF extension, cT2-weighted images with fat suppression, low signal to noise ratio and little to no motion-related artifacts were used. Two observers measured the extension of CSF from the inner table of the skull for the cranial nerves, and outside the spinal canal for the sacral nerves.Results: CSF extension (mean distance [95% CI]) was visible within the dural sheaths surrounding the majority of the cranial nerves: optic nerve (40 mm [38-42]), trigeminal nerve (16 mm [15-19]), facial-vestibulocochlear nerve (11 mm [11-12]), glossopharyngeal-vagus-accessory nerve (7 mm [7-9]) and hypoglossal nerve (8 mm [7-9]). No CSF was observed outside the spinal canal at sacral level. No significant difference between both observers was measured.Conclusion: This study generates evidence for significant CSF extension outside the inner table of the skull. Despite the vicinity of the lens and cochlea, we therefore recommend the inclusion of both optic nerves and internal auditory canals in the clinical target volume for craniospinal irradiation when using highly conformal delivery techniques.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Líquido Cefalorraquídeo/diagnóstico por imagen , Nervios Craneales/diagnóstico por imagen , Irradiación Craneoespinal/métodos , Plexo Lumbosacro/diagnóstico por imagen , Imagen por Resonancia Magnética Intervencional/métodos , Adulto , Neoplasias Encefálicas/radioterapia , Femenino , Voluntarios Sanos , Humanos , Masculino , Variaciones Dependientes del Observador , Canal Medular/diagnóstico por imagen , Adulto Joven
2.
Am J Perinatol ; 36(2): 111-117, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30112757

RESUMEN

OBJECTIVE: To evaluate the risk of preterm birth in low-risk women with cervical length (CL) ≤25 mm on transvaginal ultrasound (TVUS) managed with vaginal progesterone (VagP) therapy versus cerclage. STUDY DESIGN: This is a retrospective cohort of women with no prior history of preterm birth or cervical insufficiency and CL ≤ 25 mm on TVUS, managed with either VagP therapy alone or cerclage (with or without VagP). The primary outcome was rate of preterm delivery < 37 weeks gestational age (GA). Secondary outcomes included delivery at ≤ 32 or ≤ 28 weeks GA, premature preterm rupture of membranes, pregnancy latency, GA at delivery, and composite neonatal outcome. RESULTS: Women undergoing cerclage placement (n = 31) were older and had an earlier GA at the time of diagnosis of short cervix compared with women receiving VagP (n = 62). Delivery at < 37 weeks occurred in 21/62 (33.9%) in the VagP group and 14/31 (45.2%) in the cerclage group (adjusted odds ratio: 1.72, 95% confidence interval: 0.52, 5.66). There were no differences in secondary outcomes. CONCLUSION: Cerclage compared with VagP therapy did not decrease risk of preterm birth in women with CL ≤ 25 mm. Further research is needed to determine optimal management in such women given a residual 40% risk of preterm birth despite optimal therapy.


Asunto(s)
Cerclaje Cervical , Resultado del Embarazo , Nacimiento Prematuro/prevención & control , Progesterona/administración & dosificación , Incompetencia del Cuello del Útero/terapia , Administración Intravaginal , Adulto , Cerclaje Cervical/efectos adversos , Cuello del Útero/anomalías , Terapia Combinada , Femenino , Rotura Prematura de Membranas Fetales , Edad Gestacional , Humanos , Recién Nacido , Embarazo , Nacimiento Prematuro/epidemiología , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Riesgo , Incompetencia del Cuello del Útero/tratamiento farmacológico , Adulto Joven
3.
Am J Perinatol ; 35(12): 1131-1137, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29310142

RESUMEN

OBJECTIVE: The objective of this study is to evaluate the effect of noncephalic presentation on neonatal outcomes in preterm delivery. STUDY DESIGN: In this study a secondary analysis of the BEAM trial was performed. It included women with singleton, liveborn, and nonanomalous fetuses. Neonatal outcomes were compared in noncephalic versus cephalic presentation. Adjusted odds ratios and 95% confidence intervals were calculated for each outcome with logistic regression while controlling for possible confounders. A stratified analysis by mode of delivery was also performed in this study. RESULTS: A total of 458 noncephalic deliveries were compared with 1,485 cephalic deliveries. In multivariate analysis, noncephalic presentation was associated with increased risk of death in the neonatal intensive care unit (NICU) or death at <15 months corrected gestational age (cGA), and a decreased risk of IVH. The risk of death persisted in stratified analysis, with increased risk of death at <15 months cGA in noncephalic neonates born via cesarean delivery. In the vaginal delivery group, there was an increased risk of death at <15 months cGA and NICU death. CONCLUSION: After controlling for possible confounders, neonates who are noncephalic at delivery have higher risk for death <15 months cGA and death in the NICU while their risk of IVH is reduced. The risk of death persisted in stratified analyses by mode of delivery.


Asunto(s)
Parto Obstétrico , Mortalidad Infantil , Presentación en Trabajo de Parto , Adulto , Cesárea/estadística & datos numéricos , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Masculino , Análisis Multivariante , Embarazo , Resultado del Embarazo , Nacimiento Prematuro , Estudios Retrospectivos , Estados Unidos , Adulto Joven
4.
Am J Perinatol ; 33(2): 188-94, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26344012

RESUMEN

OBJECTIVE: To estimate the impact of admission cervical dilation on the risk of cesarean in spontaneously laboring women at term. STUDY DESIGN: Secondary analysis of a prospective cohort study of women admitted in term labor with a singleton gestation. Women with rupture of membranes before admission, induction of labor, or prelabor cesarean were excluded. The association between cesarean and cervical dilation at admission was estimated, and results were stratified by parity. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated, using cervical dilation ≥ 6 cm as the reference group. Cesarean for arrest was secondarily explored. RESULTS: A total of 2,033 spontaneously laboring women met inclusion criteria. Women admitted at <6 cm dilation had an increased risk of cesarean compared with those admitted at ≥6 cm (13.2 vs. 3.5%; RR 3.73; 95% CI 1.94-7.17). The increased risk was noted in nulliparous (16.8 vs. 7.1%; RR 2.35; 95% CI 0.90-6.13) and multiparous (11.0 vs. 2.5%; RR 4.36; 95% CI 1.80-10.52) women, but was statistically significant only in multiparous women. CONCLUSIONS: Decreasing cervical dilation at admission, particularly <6 cm, is a modifiable risk factor for cesarean, especially in multiparous women. This should be considered in the decision-making process about timing of admission in term labor.


Asunto(s)
Cesárea/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Primer Periodo del Trabajo de Parto , Paridad , Adulto , Factores de Edad , Estudios de Cohortes , Femenino , Humanos , Trabajo de Parto , Embarazo , Estudios Prospectivos , Factores de Riesgo , Nacimiento a Término , Factores de Tiempo , Adulto Joven
6.
J Matern Fetal Neonatal Med ; 34(14): 2295-2302, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31514559

RESUMEN

OBJECTIVE: To determine the prevalence of Mycoplasmataceae species in pregnant women and evaluate their association with immune system mediators. METHODS: Women were prospectively enrolled between 16-22 weeks' gestation. Vaginal swabs were self-collected and analyzed with PCR for Mycoplasma hominis (MH) and Mycoplasma genitalium (MG) as well as Ureaplasma urealyticum (UU) and Ureaplasma parvum (UP) (collectively, Myc). Immune mediators were measured via Luminex multiplex assay. Women with vaginal Mycoplasmataceae were compared to women without Myc, and women with Mycoplasma species (MH or MG) were compared to women without MH or MG. Linear regression models were used to investigate the relationship of the presence of Mycoplasmataceae on log-transformed immune mediators while controlling for confounders using propensity scores. RESULTS: One-hundred-twenty women were enrolled and had complete lab data available. Colonization was 20.8, 2.5, 10.0, and 48.3% for MH, MG, UU, and UP, respectively. Women with any Mycoplasmataceae were more likely to be younger, of the Black race, and have public insurance. There were no significant differences in immune mediators between women with vaginal Mycoplasmataceae versus those without. After controlling for confounders, women with MH and/or MG had significantly elevated levels of IL-1ß compared to women without MH or MG (estimate = 1.12; 95% CI = 0.33, 1.93). There were no other significant differences in immune mediators in women with MH and/or MG compared to those without. CONCLUSIONS: Colonization rates were highest for UP and lowest for MG. Higher IL-1ß levels were seen in the presence of MH and/or MG, indicating that these less frequently encountered organisms may incite a stronger host response. There were no other significant differences in immune mediator levels.


Asunto(s)
Infecciones por Mycoplasma , Mycoplasma genitalium , Mycoplasmataceae , Infecciones por Ureaplasma , Femenino , Humanos , Infecciones por Mycoplasma/epidemiología , Mycoplasma hominis , Embarazo , Ureaplasma , Infecciones por Ureaplasma/epidemiología , Ureaplasma urealyticum
7.
Clin Transl Radiat Oncol ; 31: 28-33, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34522796

RESUMEN

PURPOSE: Optic nerves are part of the craniospinal irradiation (CSI) target volume. Modern radiotherapy techniques achieve highly conformal target doses while avoiding organs-at-risk such as the lens. The magnitude of eye movement and its influence on CSI target- and avoidance volumes are unclear. We aimed to evaluate the movement-range of lenses and optic nerves and its influence on dose distribution of several planning techniques. METHODS: Ten volunteers underwent MRI scans in various gaze directions (neutral, left, right, cranial, caudal). Lenses, orbital optic nerves, optic discs and CSI target volumes were delineated. 36-Gy cranial irradiation plans were constructed on synthetic CT images in neutral gaze, with Volumetric Modulated Arc Therapy, pencil-beam scanning proton therapy, and 3D-conventional photons. Movement-amplitudes of lenses and optic discs were analyzed, and influence of gaze direction on lens and orbital optic nerve dose distribution. RESULTS: Mean eye structures' shift from neutral position was greatest in caudal gaze; -5.8±1.2 mm (±SD) for lenses and 7.0±2.0 mm for optic discs. In 3D-conventional plans, caudal gaze decreased Mean Lens Dose (MLD). In VMAT and proton plans, eye movements mainly increased MLD and diminished D98 orbital optic nerve (D98OON) coverage; mean MLD increased up to 5.5 Gy [total ΔMLD range -8.1 to 10.0 Gy], and mean D98OON decreased up to 3.3 Gy [total ΔD98OON range -13.6 to 1.2 Gy]. VMAT plans optimized for optic disc Internal Target Volume and lens Planning organ-at-Risk Volume resulted in higher MLD over gaze directions. D98OON became ≥95% of prescribed dose over 95/100 evaluated gaze directions, while all-gaze bilateral D98OON significantly changed in 1 of 10 volunteers. CONCLUSION: With modern CSI techniques, eye movements result in higher lens doses and a mean detriment for orbital optic nerve dose coverage of <10% of prescribed dose.

8.
Clin Perinatol ; 45(2): 307-323, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29747890

RESUMEN

Congenital cytomegalovirus is the most common viral congenital infection, and affects up to 2% of neonates. Significant sequelae may develop after congenital cytomegalovirus, including hearing loss, cognitive defects, seizures, and death. Zika virus is an emerging virus with perinatal implications; a congenital Zika virus syndrome has been identified, and includes findings such as microcephaly, fetal nervous system abnormalities, and neurologic sequelae after birth. Screening, diagnosis, prevention, and treatment of these perinatal infections are reviewed in this article.


Asunto(s)
Infecciones por Citomegalovirus/prevención & control , Tamizaje Neonatal/métodos , Complicaciones Infecciosas del Embarazo/prevención & control , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/prevención & control , Adulto , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/congénito , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/epidemiología , Femenino , Humanos , Incidencia , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Masculino , Microcefalia/diagnóstico , Microcefalia/epidemiología , Microcefalia/virología , Atención Perinatal/métodos , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/virología , Diagnóstico Prenatal/métodos , Pronóstico , Medición de Riesgo , Virus Zika/patogenicidad
9.
Obstet Gynecol Surv ; 73(2): 103-109, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29480924

RESUMEN

IMPORTANCE: Intrahepatic cholestasis of pregnancy (ICP) complicates approximately 0.2% to 2% of pregnancies and can lead to increased fetal risks in pregnancy. OBJECTIVE: This review aims to increase the knowledge of women's health care providers regarding the diagnosis, management, and fetal risks associated with ICP. RESULTS: The diagnosis of ICP is based on symptoms of pruritus that typically include the palms and soles, as well as elevated bile acid levels. Other liver function tests such as alanine aminotransferase and aspartate aminotransferase are also frequently elevated, and other causes of liver dysfunction should be ruled out. Fetal risks of ICP include increased risk of preterm birth, meconium-stained amniotic fluid, respiratory distress syndrome, or stillbirth. There is evidence that as bile acid levels increase, so does the risk of adverse neonatal outcomes. Ursodeoxycholic acid treatment has been shown to improve maternal pruritus symptoms, as well as biochemical tests, but no treatment has been shown to definitively improve fetal outcomes. CONCLUSIONS AND RELEVANCE: Providers should be aware of the signs and symptoms of ICP and provide accurate diagnosis and management of affected women. Women with a diagnosis of ICP should be treated with ursodeoxycholic acid to improve maternal symptoms. Given the increased risk of stillbirth in the setting of ICP, delivery may be considered at 37 weeks' gestation.


Asunto(s)
Colagogos y Coleréticos/uso terapéutico , Colestasis Intrahepática/diagnóstico , Colestasis Intrahepática/tratamiento farmacológico , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/tratamiento farmacológico , Diagnóstico Prenatal/métodos , Ácido Ursodesoxicólico/uso terapéutico , Adulto , Colestasis Intrahepática/complicaciones , Manejo de la Enfermedad , Femenino , Humanos , Pruebas de Función Hepática , Embarazo , Resultado del Embarazo , Nacimiento Prematuro/etiología , Prurito/diagnóstico , Prurito/etiología , Factores de Riesgo , Mortinato
10.
Obstet Gynecol ; 132(4): 882-887, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30130349

RESUMEN

BACKGROUND: Portal hypertension in pregnancy is associated with elevated risk of variceal hemorrhage. Ectopic varices, those located outside the esophagus or stomach, are rare but have a high risk of associated maternal morbidity or mortality. CASE: A 31-year-old woman, gravida 2 para 0010, with cirrhosis and portal hypertension was found to have abdominal wall ectopic varices on third-trimester obstetric ultrasonography. Computed tomography angiography confirmed these findings. Given concern for catastrophic hemorrhage during delivery, she underwent transjugular intrahepatic portosystemic shunt placement at 35 weeks of gestation, with reduction in the pressure gradient within the portosystemic circulation. She subsequently underwent an uncomplicated cesarean delivery. CONCLUSION: Identification of ectopic varices on obstetric ultrasonography may allow for treatment before delivery, decreasing the risk of serious maternal morbidity or mortality.


Asunto(s)
Pared Abdominal/irrigación sanguínea , Cirrosis Hepática/complicaciones , Derivación Portosistémica Intrahepática Transyugular , Complicaciones Cardiovasculares del Embarazo/etiología , Várices/etiología , Adulto , Femenino , Humanos , Embarazo , Complicaciones Cardiovasculares del Embarazo/diagnóstico por imagen , Complicaciones Cardiovasculares del Embarazo/cirugía , Várices/diagnóstico por imagen , Várices/cirugía
11.
PLoS One ; 9(3): e90961, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24595308

RESUMEN

Regulation of human placental syncytiotrophoblast renewal by cytotrophoblast migration, aggregation/fusion and differentiation is essential for successful pregnancy. In several tissues, these events are regulated by intermediate conductance Ca2+-activated K+ channels (IKCa), in part through their ability to regulate cell volume. We used cytotrophoblasts in primary culture to test the hypotheses that IKCa participate in the formation of multinucleated syncytiotrophoblast and in syncytiotrophoblast volume homeostasis. Cytotrophoblasts were isolated from normal term placentas and cultured for 66 h. This preparation recreates syncytiotrophoblast formation in vivo, as mononucleate cells (15 h) fuse into multinucleate syncytia (66 h) concomitant with elevated secretion of human chorionic gonadotropin (hCG). Cells were treated with the IKCa inhibitor TRAM-34 (10 µM) or activator DCEBIO (100 µM). Culture medium was collected to measure hCG secretion and cells fixed for immunofluorescence with anti-IKCa and anti-desmoplakin antibodies to assess IKCa expression and multinucleation respectively. K+ channel activity was assessed by measuring 86Rb efflux at 66 h. IKCa immunostaining was evident in nucleus, cytoplasm and surface of mono- and multinucleate cells. DCEBIO increased 86Rb efflux 8.3-fold above control and this was inhibited by TRAM-34 (85%; p<0.0001). Cytotrophoblast multinucleation increased 12-fold (p<0.05) and hCG secretion 20-fold (p<0.05), between 15 and 66 h. Compared to controls, DCEBIO reduced multinucleation by 42% (p<0.05) and hCG secretion by 80% (p<0.05). TRAM-34 alone did not affect cytotrophoblast multinucleation or hCG secretion. Hyposmotic solution increased 86Rb efflux 3.8-fold (p<0.0001). This effect was dependent on extracellular Ca2+, inhibited by TRAM-34 and 100 nM charybdotoxin (85% (p<0.0001) and 43% respectively) but unaffected by 100 nM apamin. In conclusion, IKCa are expressed in cytotrophoblasts and their activation inhibits the formation of multinucleated cells in vitro. IKCa are stimulated by syncytiotrophoblast swelling implicating a role in syncytiotrophoblast volume homeostasis. Inappropriate activation of IKCa in pathophysiological conditions could compromise syncytiotrophoblast turnover and volume homeostasis in pregnancy disease.


Asunto(s)
Fusión Celular , Placenta/citología , Canales de Potasio Calcio-Activados/metabolismo , Trofoblastos/citología , Análisis de Varianza , Bencimidazoles/farmacología , Transporte Biológico/efectos de los fármacos , Técnicas de Cultivo de Célula , Gonadotropina Coriónica/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Modelos Lineales , Canales de Potasio Calcio-Activados/efectos de los fármacos , Embarazo , Pirazoles/farmacología , Radioisótopos de Rubidio/metabolismo
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