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Placentation is a major determinant of the success of pregnancy. It is regulated by several factors such as cell adhesion molecules, tight junctions, and gap junctions. The cell adhesion molecules are integrins, cadherins, immunoglobulins, nectins, and selectins. The tight junctions are composed of claudins, occludin, and junction adhesion molecule proteins while the gap junctions are composed of connexins of varying molecular weights. During placentation, some of these molecules regulate trophoblast proliferation, trophoblast fusion, trophoblast migration, trophoblast invasion, trophoblast-endothelium adhesion, glandular remodeling, and spiral artery remodeling. There is a dysregulated placental expression of some of these molecules during obstetric complications. We have, hereby, indicated the expression patterns of the subunits of each of these molecules in the various trophoblast subtypes and in the decidua, and have highlighted their involvement in physiological and pathological placentation. The available evidence points to the relevance of these molecules as distinguishing markers of the various trophoblast lineages and as potential therapeutic targets in the management of malplacentation-mediated diseases.

Uterine deficiency of Dnmt3b impairs decidualization and consequent embryo implantation defects. Recent advances in molecular technologies have allowed the unprecedented mapping of epigenetic modifications during embryo implantation. DNA methyltransferase 3a (DNMT3A) and DNMT3B are responsible for establishing DNA methylation patterns produced through their de novo-type DNA methylation activity in implantation stage embryos and during germ cell differentiation. It was reported that conditional knockout of Dnmt3a in the uterus does not markedly affect endometrial function during embryo implantation, but the tissue-specific functions of Dnmt3b in the endometrium during embryo implantation remain poorly understood to investigate the role of Dnmt3b during peri-implantation period. Here, we generated Dnmt3b conditional knockout (Dnmt3bd/d) female mice using progesterone receptor-Cre mice and examined the role of Dnmt3b during embryo implantation. Dnmt3bd/d female mice exhibited compromised fertility, which was associated with defective decidualization, but not endometrial receptivity. Furthermore, results showed loss of Dnmt3b did not lead to altered genomic methylation patterns of the decidual endometrium during early pregnancy. Transcriptome sequencing analysis of uteri from day 6 pregnant mice identified phosphoglycerate kinase 1 (Pgk1) as one of the most variable genes in Dnmt3bd/d decidual endometrium. Potential roles of PGK1 in the decidualization process during early pregnancy were confirmed. Lastly, the compromised decidualization upon the downregulation of Dnmt3b could be reversed by overexpression of Pgk1. Collectively, our findings indicate that uterine deficiency of Dnmt3b impairs decidualization and consequent embryo implantation defects.

Folate deficiency is a major risk factor of birth defects. Mechanistic studies on folate deficiency resulting in birth defects have mainly focused on fetal development. There have been few studies on folate deficiency from the point of view of the mother's uterus. In our previous study, we demonstrated that folate deficiency inhibits apoptosis of decidual cells, thereby restraining decidualization of the endometrium and impairing pregnancy. In this study, we further investigated the potential mechanism by which folate deficiency decreases endometrial apoptosis during decidualization. To investigate whether endometrium autophagy was inhibited under folate deficiency during decidualization, we performed real-time PCR for endometrial LC3 and P62 on day 6 (D6) to D8 of pregnancy in mice, and both were significantly changed compared to non-folate-deficient mice. Western blots showed that LC3-II and P62 were also changed in folate-deficient mice. Compared with control mice, a few punctuate LC3-II structures were detected in the folate deficiency group by immunofluorescence. Transmission electron micrographs of decidual cells on D8 showed that there were no evident autophagosomes in the folate deficiency group. In addition, apoptosis-related protein analysis by western blotting, TUNEL staining and flow cytometry showed that decreased endometrial apoptosis on D8 of pregnancy under folate deficiency was reversed after treatment with rapamycin, an autophagy inducer. ROS measurement showed that the endometrium ROS level was reduced by folate deficiency and that rapamycin reversed this effect on day 8 of pregnancy. All the results suggest that inhibiting endometrial autophagy may be implicated in the decreased endometrial apoptosis under folate deficiency during decidualization.

In this article, two kinds of isotactic polypropylene (iPP)/high density molecular weight polyethylene (HDPE) blend samples were prepared by an accessible injection-molding method. These two samples contain iPP shish kebab matrix and HDPE dispersed phase (shish kebab and epitaxy crystal, respectively). The variation of microstructures upon annealing was characterized using scanning electron microscopy, differential scanning calorimetry and small-angle X-ray scattering. It was found that the variations of different crystalline structures were changed by varying annealing parameters. Only the rearrangement of partially melted chains into primary lamellae happened for the sample with epitaxy crystalline structure, which was distinguished from the sample with HDPE shish kebab structure. Moreover, the variation of the crystalline structure, crystallinity and melting point were discussed to account for the changes in mechanical properties. These results revealed the relationship among the morphology, annealing parameters and mechanical properties, which provide a practical method to industrial manufacture.

Brown coal-based materials are excellent adsorbents for reducing chromium(VI) to chromium(III) and afterward immobilizing these chromium(III) by the binding of oxygenic functional groups in adsorbents. In the study, the approach of pyrolysis is employed for the treatment of Cr-loaded solid waste. The effects of adsorbed chromium on the pyrolysis of Xilingol brown coal were studied, and the solid char residues were collected to characterize with XPS, XRD and SEM/EDX. For the pyrolysis in Ar, the mass loss rates of Cr-loaded samples were much higher than that of unloaded samples above 750 °C, together with the increase in CO and H2 emission. XPS spectra revealed that the increase in CO could be related to formation of [Cr–O–C]. For the pyrolysis in CO2, the presence of chromium was more favorable for the conversion of char, especially demineralized brown coal and kerogen. The maximum decomposition temperatures for the Cr-loaded samples were about 200 °C lower than that of unloaded samples. The char residue yields of Cr-loaded samples were obviously higher than that of corresponding unloaded samples (at 1200 °C). Finally, the chromium in the solid residue was recovered in the form of Cr2O3. The present study exploits an approach method for both brown coal waste treatment and chromium recovery.

This research focuses on high-value utilization of the lignin-derived phenol monomer and bioethanol from biorefining process. Supported-heteropolyacid is easily used as an efficient catalyst for the ethylation of phenol with bioethanol to obtain value-added products. Through adjusting the loading amount, different acidity amount and strength can be obtained, leading to the tunable selectivity to the phenol ethylation route and regioselectivity.

Scientific Reports 7: Article number: 42628; published online: 16 February 2017; updated: 03 May 2017 The Acknowledgements section in this Article is incomplete. “This work was supported by National Natural Science Foundation Project (81522013), Chongqing Outstanding Youth Grant (cstc2014jcyjjq10005), Chongqing Key Laboratory of Ophthalmology (CSTC, 2008CA5003), Chongqing Science & Technology Platform and Base Construction Program (cstc2014pt-sy10002), National Key Clinical Specialties Construction Program of China and Research and Cultivation Foundation Project of Chongqing Medical University (201407)”.

Embryo implantation is a complex process that involves synchronized crosstalk between a receptive endometrium and a functional blastocyst. It can take place only during the window of implantation, a period when a series of changes in gene expression occur in the endometrium to accept the embryo. As modulators of gene expression, microRNAs (miRNAs) have been identified as regulators of embryo implantation. To better understand how miRNAs regulate implantation and the related molecular mechanisms, we compared the expression profiles of miRNAs and messenger RNAs between implantation sites (IMs) and inter-IMs in the endometrium of pregnant mice on day 5 by microarrays. The results showed that compared with inter-IMs, 30 miRNAs were upregulated and 42 miRNAs (>2-fold) were downregulated at the IMs. By combining the results of the microarray experiments, we found that 20 upregulated pathways and 14 downregulated pathways might be subject to miRNA regulation at IMs. We also found that some miRNAs and their targets may play a key role in implantation.

A new electrochemical sensor based on a novel organic-inorganic material (PNFCTs) was proposed for detection of paracetamol in this paper. First, PNFCTs were prepared with multi-walled carbon nanotubes (MWNTs) and a derivative of 3,4,9,10-perylenetetracarboxylic dianhydride (PTC-NH2) via cross-linking method. Then, PNFCTs were coated onto the surface of the glassy carbon electrode (GCE) to form porous organic conducting polymer films (PNFCTs/GCE), which could not only increase the loading of paracetamol efficiently but also provide an interface with exceptional electrical conductivity for paracetamol. Finally, gold nanoparticles (GNPs) were attached to the electrode surface through electrodepositing method, which obtained GNPs/PNFCTs/GCE electrode. The electrochemical behavior of paracetamol on GNPs/PNFCTs/GCE was explored by cyclic voltammetrys (CVs) and differential pulse voltammograms (DPVs). The results showed that the GNPs/PNFCTs/GCE exhibited excellent electrocatalytic activity to paracetamol, which should be attributed to remarkable properties of the new composite nanomaterials with porous nanostructure and exceptional electrical conductivity. The wide liner range and detection limit were 0.3-575 and 0.1 μM, respectively. Finally, it was successfully used to detect paracetamol in dilution human serum and commercial tablets. The sensor shows great promise for simple, sensitive, and selective detection paracetamol and provides a promising approach in paracetamol clinical research and overdose diagnostic applications.

Salt effects on the aggregation behavior of tripolar zwitterionic surfactants in aqueous solutions have been investigated using surface tension, dynamic light scattering (DLS), freeze-fracture transmission electron microscopy (FF-TEM), and 1H NMR. The tripolar zwitterionic surfactants with different inter-charge spacers are [C14H29(CH3)2N+CsN+(CH3)2CH2CH2CH2SO3 −]Br− (C14CsTri, Cs = –(CH2)2–, –(CH2)6–, –(CH2)10–, and p-xylyl). It is found that the critical micelle concentration (CMC) values of the corresponding traditional zwitterionic surfactant C14H29(CH3)2N+CH2CH2CH2SO3 − (TPS) are almost constant with the increase of the NaBr concentration. However, the CMC values of C14CsTri decrease sharply at a lower NaBr concentration and then level off at a higher NaBr concentration. Moreover, the decreasing extents of the CMC values for C14C2Tri, C14C6Tri, and C14CpxTri are very close, but more significant than that for C14C10Tri, suggesting that the self-assembly ability of the tripolar zwitterionic surfactants with a longer inter-charge spacer is less sensitive to NaBr. The DLS and FF-TEM results reveal that C14C2Tri, C14C6Tri, and C14CpxTri form micelles without NaBr and that the size slightly increases with the increase of NaBr concentration, whereas micelles and vesicles coexist for C14C10Tri and TPS without NaBr and then transfer to micelles upon the addition of NaBr. The salt-induced morphological transition for C14C10Tri is further studied using 1H NMR. The addition of NaBr reduces both the electrostatic repulsion between the same charged ammoniums and the electrostatic attraction between the oppositely charged ammonium and sulfonate. Thus, the longer inter-charge spacer of C14C10Tri tends to be more bended and the sulfonate group becomes available to contact the ammonium, which promotes micellization.

Full development of a receptive uterus is necessary for embryo implantation; however, many genes that are required for the endometrial modifications that occur during this process remain unidentified. To identify novel genes that control endometrial modifications during this period, we investigated the differential gene expression profile in the endometrium of mice on days 2 (D2) (pre-implantation) and 4 (D4) of pregnancy (i.e., the implantation window) using 17-bp long serial analysis of gene expression (LongSAGE). One hundred fifty-six tags were annotated as unique transcripts. Of these, 101 tags were significantly upregulated, and 55 tags were downregulated in the D4 library relative to the D2 library. These differentially expressed genes should therefore be of increased importance in the establishment of uterine receptivity. The differential expressions of certain of the identified genes, namely, Hspa8, Tctp, Sparc, Ifitm1, Ik, serbp1 and Dnmt1, were validated by semi-quantitative RT-PCR and/or immunohistochemistry. Functional grouping analysis classified 86 of the mapped tags into 17 categories, which are closely associated with morphological modifications of the endometrium during pregnancy. Ingenuity pathways analysis revealed that the identified differentially expressed genes fell into six primary networks, which themselves contain numerous factors that are related to key modulators of signaling pathways that are vital for endometrial modifications. These findings will aid in the further understanding of the molecular events that underlie the implantation physiology in mice.

With the increase of environment temperature, more and more attentions are payed to the effects of heat stress. Cells under heat shock either are adapted to the condition or are damaged and dead. In this paper, we found that heat shock induced endoplasmic reticulum (ER) stress. ATF4, PERK, and IRE1α were induced by heat shock of 45 °C in the transcriptional level. Under the stress of 45 °C, PERK was phosphorylated and XBP1s was detected. The result indicated that heat shock could induce the ER stress. We found that heat shock of 45 °C induced the dysregulation of HSP70 and DNA-PKcs, and downregulated the expression of PARP1 and XRCC1. Further results showed that after the knockdown of ATF4 or IRE1α, the expression of DNA-PKcs and XRCC1 were increased. It was indicated that ATF4 and IRE1α could inhibit the expression of DNA-PKcs and XRCC1 under the heat stress. Our results suggested that heat shock could activate ER stress. IRE1α and ATF4, as the important ER stress molecules, could inhibit the expression of DNA repair proteins DNA-PKcs, XRCC1, and HSP70 under heat shock. Downregulation of DNA repair proteins could aggravate the cell damage that may cause cell apoptosis. This may explain that heat shock could increase the lethality of chemotherapeutic drugs on tumor cells.