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OBJECTIVE: Cold exposure (CE) before birth is one of the initial stressors that may impact mammalian pregnancy, changing placental and fetal development and affecting the health of the offspring. While glucocorticoids (GCs) participate in the body’s response to the stress of CE, the specific mechanisms of their action are unclear. This study aims to determine the effect of CE stress on the placenta and to test whether stress, caused by cold exposure in pregnancy impairs fetal development by changing placental angiogenesis via excessive GC expression. MATERIALS AND METHODS: CE rat model was created by exposing 30 SD rats to cold preconception, or during the first, second, and third weeks of pregnancy. Serum cortisol and soluble fms-like tyrosine kinase-1 (sFlt-1) expression levels, physiological index changes (food intake, body weight change and blood pressure), and pregnancy outcomes (fetal rat weight, number of live fetal rats, and placental weight) were collected at baseline and at different time points after the conception. Protein expression levels of 11 β-hydroxysteroid dehydrogenase 2 (11β-HSD2), glucocorticoid receptor, vascular endothelial growth factor A (VEGF-A), placental growth factor (PIGF), and sFlt-1 in placental tissues were measured by western blotting. Cytokeratin (CK) and laminin (LN) in trophoblasts, and α-actin in vascular smooth muscle of the spiral arteries of pregnant rats after the systemic cold treatment were assessed by immunofluorescence and visualized by fluorescent microscopy. To test the effect of 11β-HSD2 levels on the placental recasting, human first-trimester extravillous trophoblast cells (HTR8/SVneo) underwent knockdown using specific 11β-HSD2 siRNA constructs. Expression levels of 11β-HSD2 were analyzed by quantitative real-time PCR (qPCR) and into HTR8 cells, and the expression levels of the 11β-HSD2 gene in each group were measured using qPCR. Cell migration and invasion was assessed by Transwell migration assay, and sFlt-1 levels in HTR8 cells were measured by ELISA.RESULTS: CE pre-conception led to consistently increasing serum corticosterone and sFlt-1 levels throughout pregnancy, and persistently increased diastolic blood pressure (DBP) in rat CE model compared to control animals. CE during the second week of gestation (Gp.3) was associated with significantly lower placental weight (p=0.0003). Cold exposure in the third week (Gp.4) was associated with significantly (p=0.001) lower fetal weight. CE pre-conception was associated with significantly decreased placental levels of 11β-HSD2, glucocorticoid receptor, VEGF-A, PIGF, and sFlt-1 proteins and α-actin compared to the control group. Silencing 11β-HSD2 by siRNA led to reduced cell migrations and invasion, and markedly increased expression levels of sFlt-1 in HTR8/SVneo cells (p<0.05). CONCLUSIONS: Pre-conception cold exposure and during early pregnancy leads to increased GCs levels and impaired placental 11β-HSD2 activity. We suggest that the subsequent 11β-HSD2-induced increase in the sFlt-1expression during early pregnancy may affect placental vascular remodeling and change placental morphological structure and function. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of the study was to investigate the effect of induction of labor on maternal and fetal outcomes. PATIENTS AND METHODS: This retrospective case-control study included 4386 pregnant women with low-risk singleton pregnancies who underwent regular prenatal examination and successful vaginal delivery at =41 weeks and 0 days of gestation in Fujian Maternal and Child Health Hospital between January 2014 and December 2018. Clinical data of women were retrospectively divided into the induction of labor group (2007 cases) and spontaneous onset of labor group (2361 cases) based on the mode of labor initiation. Two-sample independent t-test and X2 tests were used to analyze the differences in clinical characteristics, such as maternal age and parity between the two groups. RESULTS: The induction of the labor group had a significantly longer total duration of labor (9.37±5.37 vs. 8.82±5.13 h; p<0.001), more postpartum blood loss (219.18±188.32 vs. 199.95±124.69 mL; p=0.01) and a significantly higher incidence of severe postpartum hemorrhage (PPH) comparing to the spontaneous onset of labor group [0.8% (16/2007) vs. 0.33% (8/2361); p=0.041]. However, no significant difference was found in the neonatal outcomes. After adjusting for age, induction of labor in nulliparous women was more likely to lead to PPH than the spontaneous onset of labor [2.74% (55/2007) vs. 1.65% (39/2361); odds ratio=1.557; 95% confidence interval: 1.039-2.332; p<0.05]. CONCLUSIONS: Induction of labor increases the duration of labor and postpartum blood loss, especially in primary parturient, leading to an increased risk of PPH. This increase may be related to the overall higher duration of labor, associated with IOL. Therefore, low-risk nulliparous women should try to avoid induction of labor without medical indications. [ABSTRACT FROM AUTHOR]

This meta-analysis was intended to evaluate the effects of intrauterine perfusion of peripheral blood mononuclear cells (PBMC) on the pregnancy outcomes including clinical pregnancy rates, embryo implantation rates, live birth rates and miscarriage rates of infertile women who were undergoing in vitro fertilisation (IVF) treatment. By searching Pubmed, Embase database, five articles meeting the inclusion criteria were included, and 1173 women were enrolled (intrauterine PBMC group: n = 514; NO-PBMC group: n = 659). For the entire IVF/ICSI population and one or two embryo transfer failure patients, there was no significant difference in endometrial thickness, embryo implantation rates, live birth rates, and miscarriage rates between the PBMC group and NO-PBMC group. Although the clinical pregnancy rates of the PBMC group were higher than that of the NO-PBMC group, the confidence interval was close to the line of unity. As for the patients with three or more implantation failures, the clinical pregnancy rates, embryo implantation rates and live birth rates were much higher in the PBMC group than that of the NO-PBMC group. In summary, current evidence suggests that intrauterine perfusion of PBMC can significantly improve pregnancy outcomes in patients who have three or more implantation failures.Impact statementWhat is already known on this subject? An increasing number of studies have shown that immune cells play an important role in embryo transfer. There is no reliable evidence to confirm the clinical efficacy of intrauterine perfusion of PBMC.What do the results of this study add? The current evidence suggests that intrauterine perfusion of PBMC can significantly improve pregnancy outcomes in patients who have three or more implantation failures.What are the implications of these findings for clinical practice and/or further research? To the best of our knowledge, this meta-analysis is the first to evaluate the effect of intrauterine perfusion of PBMC on pregnancy outcomes before embryo transfer. Our study indicated that intrauterine perfusion of PBMC significantly increased clinical pregnancy rates, embryo implantation rates, and live birth rates in patients who failed more than three implants. [ABSTRACT FROM AUTHOR]

Nonstoichiometric M-type barium hexaferrite compounds, with nominal compositions BaFe12+xO19+1.5x (0≤x≤0.4), have been synthesized by spark plasma sintering technique. The electron probe microanalysis shows that the excessive trivalent iron (Fe3+) ions are in the lattices of BaFe12+xO19+1.5x compounds. Both Raman and FTIR spectra reveal that the excessive Fe3+ ions spin upward. They occupy the octahedron interstices similar to the FeO6 octahedron at the 12k site and the bipyramid interstices similar to the FeO5 bipyramid at the 2b site, in the x range of 0–0.3 and x=0.4, respectively. This explains well significant enhancement in the specific saturation magnetizations for BaFe12+xO19+1.5x with increasing the x in the range of 0–0.4. The gradual increase in the coercivities has been interpreted with the augment of Fe3+ concentration in unit cell. [ABSTRACT FROM AUTHOR]

Barium and indium double-filled skutterudites BaxInyCo4Sb12-z have been synthesized by a melting method using a series of starting materials with nominal compositions Ba0.3-mInmCo4Sb12 (0≤m≤0.3). Rietveld structure refinement shows that both barium and indium occupied the Sb-icosahedron voids in skutterudite structure. The thermal vibration parameter Uiso of indium is an order of magnitude bigger than that of barium. The electron probe microanalysis data prove that the filling fraction limit of indium is about 0.22. Hall effect was measured by the Van de Pauw method at room temperature. All BaxInyCo4Sb12-z compounds exhibit n-type conduction. The temperature dependences of electrical conductivity, Seebeck coefficient, and thermal conductivity have been measured on these compounds in the range of 300–850 K. Ba0.13In0.14Co4Sb11.75 with close filling fractions for barium and indium exhibits anomalously excellent thermoelectric properties, which may be due to the presence of the localized state in the gap occupied by one electron from indium impurity. The lattice thermal conductivity of BaxInyCo4Sb12-z is significantly low compared to single barium-filled skutterudite Ba0.27Co4Sb11.85 and reached a minimum for Ba0.13In0.14Co4Sb11.75. The dimensionless thermoelectric figure of merit ZT increased with increasing temperature in the range of 300–675 K and reached a maximum value of 1.19 for Ba0.13In0.14Co4Sb11.75 at 850 K. [ABSTRACT FROM AUTHOR]

Surface modified carbonyl iron particles (SMCIPs) were synthesized by coating carbonyl iron particles with an organic reagent (N-polyether, N, N, N,-acetyloxy) 2, 6-aminion-1, 3, 4-thiadiazole dimer. The properties of these SMCIPs, including morphology, structure, and magnetic behavior, were characterized using scanning electron microscopy and a vibrating sample magnetometer. Aqueous magnetorheological (MR) fluids were prepared using SMCIPs. MR properties were measured via a strain-controlled parallel disk rheometer equipped with a magnetic field source. Addition of the organic surface coating layer was found to greatly improve sedimentation stability of the aqueous MR fluids at a small cost of a reduction in field dependent yield stress. [ABSTRACT FROM AUTHOR]