Chromosome 19 microRNA cluster enhances cell reprogramming by inhibiting epithelial-to-mesenchymal transition.

During implantation, cytotrophoblasts undergo epithelial-to-mesenchymal transition (EMT) as they differentiate into invasive extravillous trophoblasts (EVTs). The primate-specific microRNA cluster on chromosome 19 (C19MC) is exclusively expressed in the placenta, embryonic stem cells and certain cancers however, its role in EMT gene regulation is unknown. In situ hybridization for miR-517a/c, a C19MC cistron microRNA, in first trimester human placentas displayed strong expression in villous trophoblasts and a gradual decrease from proximal to distal cell columns as cytotrophoblasts differentiate into invasive EVTs.

Decreased LIN28B in preeclampsia impairs human trophoblast differentiation and migration.

Preeclampsia (PE) is a common cause of maternal morbidity, characterized by impaired trophoblast invasion and spiral artery transformation resulting in progressive uteroplacental hypoxia. Given the primary role of LIN28A and LIN28B in modulating cell metabolism, differentiation, and invasion, we hypothesized that LIN28A and/or LIN28B regulates trophoblast differentiation and invasion, and that its dysregulation may contribute to PE. Here we show that LIN28B is expressed ∼1300-fold higher than LIN28A in human term placenta and is the predominant paralog expressed in primary human trophoblast cultures.

Modulation of LIN28B/Let-7 Signaling by Propranolol Contributes to Infantile Hemangioma Involution.

Objective: Infantile hemangiomas (IHs) are the most common benign vascular neoplasms of infancy, characterized by a rapid growth phase followed by a spontaneous involution, or triggered by propranolol treatment by poorly understood mechanisms. LIN28/let-7 axis plays a central role in the regulation of stem cell self-renewal and tumorigenesis. However, the role of LIN28B/let-7 signaling in IH pathogenesis has not yet been elucidated.

Telomere shortening and DNA damage of embryonic stem cells induced by cigarette smoke.

Embryonic stem cells (ESCs) provide a valuable in vitro model for testing toxicity of chemicals and environmental contaminants including cigarette smoke. Mouse ESCs were acutely or chronically exposed to smoke components, cigarette smoke condensate (CSC), or cadmium, an abundant component of CSC, and then evaluated for their self-renewal, apoptosis, DNA damage and telomere function. Acute exposure of ESCs to high dose of CSC or cadmium increased DNA damage and apoptosis.

Fetal umbilical cord blood erythropoietin, interleukin-6, pH, pO(2), pCO(2), and base excess levels in histologic and/or clinical chorioamnionitis: is the response only inflammatory?

Objective: To determine the correlation of histological chorioamnionitis (CA) with and without clinical CA with umbilical cord blood gases, erythropoietin (EPO), and interleukin-6 (IL-6) levels.

Methods: Umbilical artery blood gas analysis (pH, pO(2), pCO(2), BE) and umbilical vein EPO and IL-6 levels were measured in 202 infants from normal, histological, and no clinical CA and histological plus clinical CA pregnancies.

Results: Umbilical artery blood gas analyses were not different between normal controls and histological and clinical CA groups.

Are placental chorionic capillary nucleated red blood cell counts useful compared to umbilical cord blood tests?

Objective: To compare measurement of fetal nucleated red blood cell (NRBC) counts in paired histologic samples of the placenta and umbilical cord bloods.

Method: Forty-five randomly selected pregnancies had two determinations of the NRBC count. A sample of umbilical venous blood had a NRBC count measured and sections of the placenta were examined for their villous capillary NRBC counts.

Prediction of ABOG written examination performance from the third-year CREOG in-training examination results.

Objective: To study the ability of the Council on Resident Education in Obstetrics and Gynecology (CREOG) in-training examination score to predict American Board of Obstetrics and Gynecology (ABOG) written examination performance.

Study Design: Twenty-six physicians took the CREOG examination during the third year of their residency and the ABOG written examination during their fourth year. These 2 test scores were compared.

New potential regulators of uterine leiomyomata from DNA arrays: the ionotropic glutamate receptor GluR2.

In the post-Genome era, new concepts emerge about the growth regulation of uterine leiomyomata. Screening of leiomyoma and myometrial tissues with DNA arrays revealed numerous genes up-regulated in leiomyomata that were not known to be expressed in the human uterus. GluR2, a subunit of a ligand-gated cation channel, is up-regulated in leiomyomata relative to myometrium by 15- to 30-fold at the protein and mRNA level and is localized in endothelial cells.

Strategy for elucidating differentially expressed genes in leiomyomata identified by microarray technology.

Objective: cDNA microarray technology identifies genes that are differentially expressed between tissues. Our previous study identified several genes that might contribute to the fibroid phenotype. We therefore sought to confirm genes involved in three distinct signal transduction pathways.

Dose variation that is associated with approximated one-quarter tablet doses of misoprostol.

Objective: The purpose of this study was to evaluate dose variation in approximated one-quarter tablet misoprostol fragments.

Study Design: Misoprostol 100 microg tablets were weighed, separated into two lots, and quartered with a razor blade or a pill cutter. Fragments were reweighed, and the misoprostol content was determined by high-performance liquid chromatography mass spectroscopy.

Insights from gene arrays on the development and growth regulation of uterine leiomyomata.

Objective: To use microarray analysis as an unbiased approach to identify genes involved in the induction and growth of uterine leiomyomata.

Design: Screen by arrays for up to 12,000 genes in leiomyoma (L) and control myometrium (M) from nine patients.

Setting: University research laboratories.