The Expression and Localization of N-Myc Downstream-Regulated Gene 1 in Human Trophoblasts

The protein N-Myc downstream-regulated gene 1 (NDRG1) is implicated in the regulation of cell proliferation, differentiation, and cellular stress response. NDRG1 is expressed in primary human trophoblasts, where it promotes cell viability and resistance to hypoxic injury. The mechanism of action of NDRG1 remains unknown. To gain further insight into the intracellular action of NDRG1, we analyzed the expression pattern and cellular localization of endogenous NDRG1 and transfected Myc-tagged NDRG1 in human trophoblasts exposed to diverse injuries. In standard conditions, NDRG1 was diffusely expressed in the cytoplasm at a low level. Hypoxia or the hypoxia mimetic cobalt chloride, but not serum deprivation, ultraviolet (UV) light, or ionizing radiation, induced the expression of NDRG1 in human trophoblasts and the redistribution of NDRG1 into the nucleus and cytoplasmic membranes associated with the endoplasmic reticulum (ER) and microtubules. Mutation of the phosphopantetheine attachment site (PPAS) within NDRG1 abrogated this pattern of redistribution. Our results shed new light on the impact of cell injury on NDRG1 expression patterns, and suggest that the PPAS domain plays a key role in NDRG1's subcellular distribution. © 2013 Shi et al

Stillbirth is associated with perceived alterations in fetal activity - findings from an international case control study

Background Stillbirth after 28 weeks gestation affects between 1.3–8.8 per 1000 births in high-income countries. The majority of stillbirths in this setting occur in women without established risk factors. Identification of risk factors which could be identified and managed in pregnancy is a priority in stillbirth prevention research. This study aimed to evaluate women’s experiences of fetal movements and how these relate to stillbirth. Methods An international internet-based case–control study of women who had a stillbirth ≥28 weeks’ gestation within 30 days prior to completing the survey (n = 153) and women with an ongoing pregnancy or a live born child (n = 480). The online questionnaire was developed with parent stakeholder organizations using a mixture of categorical and open–ended responses and Likert scales. Univariate and multiple logistic regression was used to determine crude (unadjusted) and adjusted odds ratios (aOR) with 95% confidence intervals (CI). Summative content analysis was used to analyse free text responses. Results Women whose pregnancy ended in stillbirth were less likely to check fetal movements (aOR 0.54, 95% CI 0.35–0.83) and were less likely to be told to do so by a health professional (aOR 0.55, 95% CI 0.36–0.86). Pregnancies ending in stillbirth were more frequently associated with significant abnormalities in fetal movements in the preceding two weeks; this included a significant reduction in fetal activity (aOR 14.1, 95% CI 7.27–27.45) or sudden single episode of excessive fetal activity (aOR 4.30, 95% CI 2.25–8.24). Cases described their perception of changes in fetal activity differently to healthy controls e.g. vigorous activity was described as “frantic”, “wild” or “crazy” compared to “powerful” or “strong”. Conclusions Alterations in fetal activity are associated with increased risk of stillbirth. Pregnant women should be educated about awareness of fetal activity and reporting abnormal activity to health professionals

Confirmation of a pi_1^0 Exotic Meson in the \eta \pi^0 System

The exclusive reaction $\pi^- p \to \eta \pi^0 n$, $\eta \to \pi^+ \pi^- \pi^0$ at 18 GeV$/c$ has been studied with a partial wave analysis on a sample of 23~492 $\eta \pi^0 n$ events from BNL experiment E852. A mass-dependent fit is consistent with a resonant hypothesis for the $P_+$ wave, thus providing evidence for a neutral exotic meson with $J^{PC} = 1^{-+}$, a mass of $1257 \pm 20 \pm 25$ MeV$/c^2$, and a width of $354 \pm 64 \pm 60$ MeV$/c^2$. New interpretations of the meson exotics in neutral $\eta \pi^0$ system observed in E852 and Crystal Barrel experiments are discussed.Comment: p3, rewording the paragraph (at the bottom) about the phase variations. p4, rewording paragrath "The second method ..." . p4, at the bottom of paragrath "The third method ..." added consistent with the results of methods 1 and 2

An upper limit on hypertriton production in collisions of Ar(1.76 AGeV)+KCl

A high-statistic data sample of Ar(1.76 AGeV)+KCl events recorded with HADES is used to search for a hypertriton signal. An upper production limit per centrality-triggered event of $1.04$ x $10^{-3}$ on the $3\sigma$ level is derived. Comparing this value with the number of successfully reconstructed $\Lambda$ hyperons allows to determine an upper limit on the ratio $N_{_{\Lambda}^3H}/N_{\Lambda}$, which is confronted with statistical and coalescence-type model calculations

Production of Sigma{\pm}pi?pK+ in p+p reactions at 3.5 GeV beam energy

We study the production of Sigma^+-pi^+-pK^+ particle quartets in p+p reactions at 3.5 GeV kinetic beam energy. The data were taken with the HADES experiment at GSI. This report evaluates the contribution of resonances like Lambda(1405$, Sigma(1385)^0, Lambda(1520), Delta(1232), N^* and K^*0 to the Sigma^+- pi^-+ p K+ final state. The resulting simulation model is compared to the experimental data in several angular distributions and it shows itself as suitable to evaluate the acceptance corrections properly.Comment: 15 pages, 5 figure

Baryonic resonances close to the Kbar-N threshold: the case of Sigma(1385)^+ in pp collisions

We present results of an exclusive measurement of the first excited state of the Sigma hyperon, Sigma(1385)^+, produced in p+p -> Sigma^+ + K^+ + n at 3.5 GeV beam energy. The extracted data allow to study in detail the invariant mass distribution of the Sigma(1385)^+. The mass distribution is well described by a relativistic Breit-Wigner function with a maximum at m_0 = 1383.2 +- 0.9 MeV/c^2 and a width of 40.2 +- 2.1 MeV/c^2. The exclusive production cross-section comes out to be 22.27 +- 0.89 +- 1.56 +3.07 -2.10 mu b. Angular distributions of the Sigma(1385)^+ in different reference frames are found to be compatible with the hypothesis that 33 % of Sigma(1385)^+ result from the decay of an intermediate Delta^{++} resonance.Comment: 12 pages; 12 figures; submitted to PR

Inclusive pion and eta production in p+Nb collisions at 3.5 GeV beam energy

Data on inclusive pion and eta production measured with the dielectron spectrometer HADES in the reaction p+93Nb at a kinetic beam energy of 3.5 GeV are presented. Our results, obtained with the photon conversion method, supplement the rather sparse information on neutral meson production in proton-nucleus reactions existing for this bombarding energy regime. The reconstructed e+e-e+e- transverse-momentum and rapidity distributions are confronted with transport model calculations, which account fairly well for both pi0 and eta production.Comment: 12 pages, 9 figures, submitted to Physical Review

Study of the quasi-free np→npπ+π−np \to np \pi^+\pi^- reaction with a deuterium beam at 1.25 GeV/nucleon

The tagged quasi-free $np \to np\pi^+\pi^-$ reaction has been studied experimentally with the High Acceptance Di-Electron Spectrometer (HADES) at GSI at a deuteron incident beam energy of 1.25 GeV/nucleon ($\sqrt s \sim$ 2.42 GeV/c for the quasi-free collision). For the first time, differential distributions for $\pi^{+}\pi^{-}$ production in $np$ collisions have been collected in the region corresponding to the large transverse momenta of the secondary particles. The invariant mass and angular distributions for the $np\rightarrow np\pi^{+}\pi^{-}$ reaction are compared with different models. This comparison confirms the dominance of the $t$-channel with $\Delta\Delta$ contribution. It also validates the changes previously introduced in the Valencia model to describe two-pion production data in other isospin channels, although some deviations are observed, especially for the $\pi^{+}\pi^{-}$ invariant mass spectrum. The extracted total cross section is also in much better agreement with this model. Our new measurement puts useful constraints for the existence of the conjectured dibaryon resonance at mass M$\sim$ 2.38 GeV and with width $\Gamma\sim$ 70 MeV