Comparative analysis between endometrial proteomes of pregnant and non-pregnant ewes during the peri-implantation period

Background： Early pregnancy failure has a profound impact on both human reproductive health and animal production. 2/3 pregnancy failures occur during the peri-implantation period; however, the underlying mechanism（s） remains unclear. Well-organized modification of the endometrium to a receptive state is critical to establish pregnancy Aberrant endometrial modification during implantation is thought to be largely responsible for early pregnancy loss. Result： In this study, using well-managed recipient ewes that received embryo transfer as model, we compared the endometrial proteome between pregnant and non-pregnant ewes during implantation period. After embryo transfer, recipients were assigned as pregnant or non-pregnant ewes according to the presence or absence of an elongated conceptus at Day 17 of pregnancy. By comparing the endometrial proteomic profiles between pregnant and non-pregnant ewes, we identified 94 and 257 differentially expressed proteins （DEPs） in the endometrial caruncular and intercaruncular areas, respectively. Functional analysis showed that the DEPs were mainly associated with immune response, nutrient transport and utilization, as well as proteasome-mediated proteolysis. Conclusion： These analysis imply that dysfunction of these biological processes or pathways of DEP in the endometrium is highly associated with early pregnancy loss. In addition, many proteins that are essential for the establishment of pregnancy showed dysregulation in the endometrium of non-pregnant ewes. These proteins, as potential candidates, may contribute to early pregnancy loss.

Association of a missense mutation in the luteinizing hormone/choriogonadotropin receptor gene (LHCGR) with superovulation traits in Chinese Holstein heifers

Background： Upon binding luteinizing hormone in the ovary, the luteinizing hormone/choriogonadotropin receptor （LHCGR） is necessary for follicular maturation and ovulation, as well as luteal function. We detected mutations in the LHCGR gene and evaluated their association with superovulation. Methods： Using polymerase chain reaction-single strand sequencing, we examined polymorphisms in LHCGR and Chinese Holstein heifers. conformation polymorphism （PCR-SSCP） and DNA the genotypes associated with superovulation traits in 127 Results： A G/T polymorphism （ss52050737） in exon 11 was significantly associated with the total number of ova and the number of transferable embryos. Conclusions： LHCGR may be a new predictor for superovulation in Chinese Holstein heifers.

The proteome of IVF-induced aberrant embryo-maternal crosstalk by implantation stage in ewes

Background:Implantation failure limits the success of in vitro fertilization and embryo transfer(IVF-ET).Wellorganized embryo-maternal crosstalk is essential for successful implantation.Previous studies mainly focused on the aberrant development of in vitro fertilized(IVF)embryos.In contrast,the mechanism of IVF-induced aberrant embryo-maternal crosstalk is not well defined.Results:In the present study,using ewes as the model,we profiled the proteome that features aberrant IVF embryo-maternal crosstalk following IVF-ET.By comparing in vivo(IVO)and IVF conceptuses,as well as matched endometrial caruncular(C)and intercaruncular(IC)areas,we filtered out 207,295,and 403 differentially expressed proteins(DEPs)in each comparison.Proteome functional analysis showed that the IVF conceptuses were characterized by the increased abundance of energy metabolism and proliferation-related proteins,and the decreased abundance of methyl metabolism-related proteins.In addition,IVF endometrial C areas showed the decreased abundance of endometrial remodeling and redox homeostasis-related proteins;while IC areas displayed the aberrant abundance of protein homeostasis and extracellular matrix(ECM)interaction-related proteins.Based on these observations,we propose a model depicting the disrupted embryo-maternal crosstalk following IVF-ET:Aberrant energy metabolism and redox homeostasis of IVF embryos,might lead to an aberrant endometrial response to conceptus-derived pregnancy signals,thus impairing maternal receptivity.In turn,the suboptimal uterine environment might stimulate a compensation effect of the IVF conceptuses,which was revealed as enhanced energy metabolism and over-proliferation.Conclusion:Systematic proteomic profiling provides insights to understand the mechanisms that underlie the aberrant IVF embryo-maternal crosstalk.This might be helpful to develop practical strategies to prevent implantation failure following IVF-ET.

Comparative analysis of proteomic profiles between endometrial caruncular and intercaruncular areas in ewes during the peri-implantation period

The endometrium of sheep consists of plenty of raised intercaruncular areas （IC）. In order to better understand aglandular areas called caruncular （C）, and intensely glandular the endometrium involved mechanisms of implantation, we used LC-MS/MS technique to profile the proteome of ovine endometrial C areas and IC areas separately during the peri-implantation period, and then compared the proteomic profiles between these two areas. We successfully detected 1740 and 1813 proteins in C areas and IC areas respectively. By comparing the proteome of these two areas, we found 170 differentially expressed proteins （DEPs） （P 〈 0.05）, functional bioinformatics analysis showed these DEPs were mainly involved in growth and remodeling of endometrial tissue, cell adhesion and protein transport, and so on Our study, for the first time, provided a proteomic reference for elucidating the differences between C and IC areas, as an integrated function unit respectively, during the peri-implantation period. The results could help us to better understand the implantation in the ewes. In addition, we established a relatively detailed protein database of ovine endometrium, which provide a unique reference for further studies.

Numerical analysis on the transport properties and residence time distribution of ribbon biomass particles in a riser reactor based on CFD-DEM approach

A bended ribbon biomass particle model was developed to explore the dynamic transport properties inside a riser reactor.Residence time distribution(RTD)of the particles was analyzed by using the Eulerian-Lagrange method.The effects of sampling height,particle density,particle size and gas-to-solid mass ratio on RTD were investigated.The coupled Computational Fluid Dynamics and Discrete Element Method(CFD-DEM)model was verified firstly by experimental data on pressure drop and residence time distribution density function.The simulation results demonstrated that the ribbon biomass particles display a typical annular-core spatial distribution during transportation.The RTD of particles exhibit an approximate single-peaked normal distribution.The mean residence time(MRT)can reach up to 0.7 s when the particle density is 1200 kg/m^(3).Particle with higher density has longer mean residence time.The flow patterns are closer to plug flow if particle length over 12 mm.The particle flow pattern is not sensitive to changes in particle density and size,while the gas-to-material mass ratio has a significant impact on it.

Study on self-healing and corrosion resistance behaviors of functionalized carbon dot-intercalated graphene-based waterborne epoxy coating

Functionalized carbon dots(CDs)obtained from citric acid derivative were selected as intercalatorto modify graphene and then dispersed into epoxy matrix to prepare CDs modified graphene/epoxy(CDs-G/EP)coatings.Meanwhile,their microstructure,self-healing and corro sion resistance behaviors were analyzed deeply.Structural characterizations indicated the formation of"π-π"interaction between functionalized carbon dots and graphene.By observation,the dispersion and interface compatibility of graphene were greatly enhanced by CDs.The change rules of electrochemistry results implied that the addition of 0.5 wt.%CDs-G in EP coating(CDs-G0.5%/EP)demonstrated a superior protective property on steel,which was attributed to the physical barrier of highly dispersed graphene and the self-healing ability of CDs.After 50 days immersion,the oxygen permeability coefficient and water absorption of CDs-G0.5%/EP coating were only 4.27×10^(-13)cm^(3)cm cm^(-2)s^(-1)Pa^(-1) and 4.4%,respectively.

Corrosion Resistance of Graphene-Reinforced Waterborne Epoxy Coatings

Graphene （G） was dispersed uniformly in water and used as an inhibitor in waterborne epoxy coatings. The effect of dispersed G on anticorrosion performance of epoxy coatings was evaluated. The composite coatings displayed outstanding barrier properties against H20 molecule compared to the neat epoxy coating. Open circuit potential （OCP）, Tafel and electrochemical impedance spectroscopy （EIS） analysis confirmed that the corrosion rate exhibited by composite coatings with 0.5 wt% G was an order of magnitude lower than that of neat epoxy coating. Salt spray test results revealed superior corrosion resistance offered by the composite coating.

A mussel-inspired delivery system for enhancing self-healing property of epoxy coatings

Dopamine(DA), one type of mussel-inspired biological molecules with adhesive nature and corrosion inhibitor property, are often used to functionalize the surfaces of various materials. Herein, we report the application of polydopamine(PDA) microcapsules as novel nanocontainers for the purpose, loading corrosion inhibitor(benzotriazole) in its shell structure, and then were embedded into epoxy coatings to provide self-healing and anti-corrosion protection for carbon steel. Fast release of benzotriazole in acidic environment caused by local corrosion and the chelating effect of PDA-Fe^(3+)can synergistically promote the formation of protective film on bare steel surface, which endows coatings with self-healing functionality. Electrochemical impedance spectroscopy(EIS), local electrochemical impedance spectroscopy(LEIS), and spray tests were conducted to evaluate the active inhibition and corrosion resistance of the loaded coatings. The scratched coating with incorporation of nanocontainers presented better protection performance, exhibiting increased Ro(oxide layer resistance) and R ct(charge transfer resistance) during initial immersion periods. The EIS tests in long-term immersion were also performed to confirm the anti-corrosion effect of composited coatings. These results demonstrated that benzotriazole-decorated PDA capsules dramatically enhanced the self-healing properties and anti-corrosion performance of epoxy coatings with the synergistic help of PDA and benzotriazole.