Fetal MPA Doppler velocimetry can reliably be obtained throughout gestation. AT and AT/ET ratios of the fetal MPA Doppler waveform may help identifying fetuses at risk of developing neonatal RDS.

The mechanisms regulating the cellular distribution of STAT family transcription factors remain poorly understood. To identify regions of Stat5B required for ligand-induced nuclear accumulation, we constructed a cDNA encoding green fluorescent protein (GFP) fused to the N terminus of Stat5B and performed site-directed mutagenesis. When co-expressed with growth hormone (GH) receptor in COS-7 cells, GFP-Stat5B is tyrosylphosphorylated, forms dimers, and binds DNA in response to GH in a manner indistinguishable from untagged Stat5B. In multiple cell types, laser scanning confocal imaging of GFP-Stat5B co-expressed with GH receptor shows that GFP-Stat5B undergoes a rapid, dramatic accumulation in the nucleus upon GH stimulation. We introduced alanine substitutions in several regions of Stat5B and assayed for GH-dependent nuclear localization. Only the mutation that prevented binding to DNA ( 466 VVVI 469 ) abrogated GH-stimulated nuclear localization. This mutant fusion protein is tyrosyl-phosphorylated and dimerizes in response to GH. These results suggest that either high affinity binding to DNA contributes to nuclear accumulation of Stat5B or that this region is crucial for two functions, namely accumulation of Stat5B in the nucleus and DNA binding. Thus, we have identified a mutant Stat5 defective in nuclear localization despite its ability to be tyrosyl-phosphorylated and to dimerize.

Congenital vascular rings can be diagnosed with prenatal ultrasound using the three-vessel trachea view and subsequent fetal echocardiography with particular attention to the relationship of the aortic arches, ductal arches, and the trachea.

Signal transducers and activators of transcription (Stat) are latent transcription factors that participate in cytokine signaling by regulating the expression of early response genes. Our previous studies showed that Stat5 functions not only as a transcriptional activator but also as a transcriptional inhibitor, depending on the target promoter. This report further investigates the mechanism of Stat5b-mediated inhibition and demonstrates that PRL-inducible Stat5b inhibits nuclear factorkappaB (NFkappaB) signaling to both the interferon regulatory factor-1 promoter and to the thymidine kinase promoter containing multimerized NFkappaB elements (NFkappaB-TK). Further, PRL-inducible Stat5b inhibits tumor necrosis factor-alpha signaling presumably by inhibiting endogenous NFkappaB. This Stat5b-mediated inhibitory effect on NFkappaB signaling is independent of Stat5b-DNA interactions but requires the carboxyl terminus of Stat5b as well as Stat5b nuclear translocation and/or accumulation, suggesting that Stat5b is competing for a nuclear factor(s) necessary for NFkappaB-mediated activation of target promoters. Increasing concentrations of the coactivator p300/CBP reverses Stat5b inhibition at both the interferon-regulatory factor-1 and NFkappaB-TK promoters, suggesting that Stat5b may be squelching limiting coactivators via protein-protein interactions as one mechanism of promoter inhibition. These results further substantiate our observation that Stat factors can function as transcriptional inhibitors. Our studies reveal cross-talk between the Stat5b and NFkappaB signal transduction pathways and suggest that Stat5b-mediated inhibition of target promoters occurs at the level of protein-protein interactions and involves competition for limiting coactivators.

Human and murine receptors for tumor necrosis factor alpha (TNF-a) are present on most somatic cells and have been characterized and cloned. In contrast, very little is currently known about whether TNF-cK can bind to pathogens and whether such binding results in important biological consequences for the infected host. We now report that a number of gram-negative bacteria have receptors for TNF-a. Using '25I-labeled TNF-ax, weshow that ShigeUaflexneri has 276 receptors for TNF-ax, with a Kd of 2.5 nM. The binding of labeled TNF-ae to these bacterial receptors can be inhibited by cold TNF-a but not by cold TNF-13. Binding of 125I-TNF-a to S. flexneri was inhibited by trypsin treatment of bacterial cells or incubation at 52°C for 3 min. Monoclonal antibody to either the 55-kDa or the 75-kDa TNF-aK receptor, which are present on different eukaryotic cells, had no effect on 125I-TNF-a binding to bacteria. A number of gram-negative bacteria were capable of binding 830

No abstract

Objective-To test the hypothesis that inflammation modulates fetal erythroblastosis and/or the release of NRBCs independent of hypoxia or fetal stress. We sought to determine if fetal inflammation is associated with an elevation in neonatal NRBC count in the setting of inflammation-associated preterm birth.Study Design-The relationships between peripheral NRBC count, histological chorioamnionitis, umbilical cord interleukin-6 (IL-6), erythropoietin (EPO), cortisol and acid-base status were analyzed in 68 preterm singletons, born to mothers who had an amniocentesis to rule out infection. Proteomic profiling of amniotic fluid identified presence of intra-amniotic inflammation according to established parameters. NRBC counts were assessed within 1-hour of birth. Early-onset neonatal sepsis (EONS) was established based on hematological and microbiological indices. IL-6, EPO and cortisol levels were measured by immunoassays. Fetal acid-base status was determined within 10 minutes of delivery. Parametric or nonparametric statistics was employed.Results-Fetuses with EONS (n=19) were delivered at earlier gestational ages (mean±SD: 27.1±2.8 weeks, P=0.001) and more often by mothers with intra-amniotic inflammation (P=0.022) and histological chorioamnionitis (P<0.001). Neonates with EONS had higher absolute NRBCs Condensation:In inflammation-associated preterm birth and in the absence of hypoxia, elevated neonatal nucleated red blood cell counts may be a direct response to inflammatory mediators. Authors' Contributions:Antonette Dulay is the principal investigator and responsible author. Antonette Dulay, Irina Buhimschi and Catalin Buhimschi designed the study, generated, interpreted the data and wrote the initial draft of the manuscript. Guomao Zhao participated with processing of biological samples, performed immunoassays, revised critically the manuscript and approved the final version. Vineet Bhandari participated with aspects of data analysis and interpretation, revised critically the manuscript and approved the final version. Guoyang Luo; Sonya Abdel-Razeq; Michael Cackovic, Victor Rosenberg, Christian Pettker Stephen Thung and Mert Ozan Bahtiyar participated with patient enrollment, acquisition of demographic and clinical data, critical revision of the manuscript and approved the final version. NIH Public AccessAuthor Manuscript Am J Obstet Gynecol. Author manuscript; available in PMC 2014 May 16. Published in final edited form as: Am J Obstet Gynecol. 2008 April ; 198(4): 426.e1-426.e9. doi:10.1016/j.ajog.2008 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript counts (P=0.011). NRBC counts were directly correlated with cord blood IL-6 levels (P<0.001) but not with EPO, cortisol or parameters of acid-base status levels regardless of EONS status. These relationships remained following correction for gestational age, diabetes, intrauterine growth restriction (IUGR) and steroid exposure.Conclusion-In the setting of inflammation-associated preterm birth and in the absence of hypoxia,...

Intra-amniotic infection/inflammation (IAI) is a major cause of preterm birth, but the mechanisms responsible are not well understood. This study investigates the effects of IAI on vascular endothelial growth factor (VEGF) as well as VEGF receptor (Flt1, KDR2) and coreceptor (neuropilin-1 and -2) messenger RNA (mRNA) and protein expression at the maternal-fetal interface, both in vitro and in vivo. Decidual stromal cells (DSCs) were isolated from term placentae, purified, and treated with 10(-8) mol/L estradiol (E(2)), 10( -7) mol/L medroxyprogesterone acetate (MPA), both, or vehicle for 7 days. Vascular endothelial growth factor expression in cultured DSCs increased in response to stimulation with interleukin 1 beta (IL-1 beta; 0.01-10 ng/mL)--but not tumor necrosis factor alpha (TNF-alpha; 1 ng/mL)--in a concentration-dependent fashion irrespective of the hormonal milieu. This effect appears to be mediated at the level of gene transcription because stimulation with IL-1 beta (but not TNF-alpha) increased expression of VEGF mRNA as measured by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR); a similar increase was seen in neuropilin-1/-2 (but not Flt1 and KDR2) mRNA. Immunohistochemical studies confirmed these observations in vivo. Immunostaining for VEGF and neuropilin-1/-2 (but not Flt1 or KDR2) was increased in serial tissue sections of decidua from women with clinical and histological evidence of IAI versus noninfected controls, and in cultured term DSCs exposed to IL-1 beta. The novel observations that IL-1 beta stimulates VEGF and neuropilin-1/-2 mRNA and protein expression in term DSCs in vitro along with confirmatory in vivo data using immunohistochemistry provide a mechanism by which IAI can alter vascular permeability, thereby facilitating leukocyte trafficking and increasing the risk of abruption, both of which are associated with preterm birth.