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A particle-resolved model is implemented to investigate the performance of porous catalyst during the methane bi-reforming process, where the reaction and diffusion inside the catalyst particle are considered. The difference of specific surface area between pore structures is also taken into consideration. The performance of monodisperse and bi-disperse catalysts is evaluated. The results reveal that the bi-reforming process depends on the competition and coordination between dry reforming reaction and steam reforming reaction. The pore size doses not monotonously influence the ratio of hydrogen to carbon monoxide production. For the bi-disperse pore catalyst, owing to the synergistic effect of diffusion and reaction, there exists an optimal macropore fraction of 0.5 for hydrogen generation rate. There is an optimal macro-pore size of about 10 μ m to achieve a stable hydrogen production rate. • Particle-resolved simulation is conducted for bi-reforming process of catalyst. • Dependence of catalyst behaviors on pore structure parameter is evaluated. • There exists an optimal macro-pore fraction of 0.5–0.7 for hydrogen production. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2006.04.451 Byline: Manli Chuai (a), Wei Zeng (b), Xuesong Yang (a), Veronika Boychenko (a), James A. Glazier (b), Cornelis J. Weijer (a) Keywords: Primitive streak; Cell division; Cell intercalation; FGF signalling Abstract: Gastrulation in amniotes begins with extensive re-arrangements of cells in the epiblast resulting in the formation of the primitive streak. We have developed a transfection method that enables us to transfect randomly distributed epiblast cells in the Stage XI-XIII chick blastoderms with GFP fusion proteins. This allows us to use time-lapse microscopy for detailed analysis of the movements and proliferation of epiblast cells during streak formation. Cells in the posterior two thirds of the embryo move in two striking counter-rotating flows that meet at the site of streak formation at the posterior end of the embryo. Cells divide during this rotational movement with a cell cycle time of 6-7 h. Daughter cells remain together, forming small clusters and as result of the flow patterns line up in the streak. Expression of the cyclin-dependent kinase inhibitor, P21/Waf inhibits cell division and severely limits embryo growth, but does not inhibit streak formation or associated flows. To investigate the role off cell-cell intercalation in streak formation we have inhibited the Wnt planar-polarity signalling pathway by expression of a dominant negative Wnt11 and a Dishevelled mutant Xdd1. Both treatments do not result in an inhibition of streak formation, but both severely affect extension of the embryo in later development. Likewise inhibition of myosin II which as been shown to drive cell-cell intercalation during Drosophila germ band extension, has no effect on streak formation, but also effectively blocks elongation after regression has started. These experiments make it unlikely that streak formation involves known cell-cell intercalation mechanisms. Expression of a dominant negative FGFR1c receptor construct as well as the soluble extracellular domain of the FGFR1c receptor both effectively block the cell movements associated with streak formation and mesoderm differentiation, showing the importance of FGF signalling in these processes. Author Affiliation: (a) Division of Cell and Developmental Biology, Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK (b) Biocomplexity Institute and Department of Physics, Swain Hall West 159, Indiana University, 727 East Third Street, Bloomington, IN 47405-7105, USA Article History: Received 27 December 2005; Revised 5 April 2006; Accepted 7 April 2006

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2005.04.021 Byline: Cheng Cui (a), Xuesong Yang (b), Manli Chuai (b), James A. Glazier (a), Cornelis J. Weijer (b) Keywords: Primitive streak; Cell movement; Cell proliferation; FGF signalling; Time-lapse analysis; Vector velocity field Abstract: We have investigated the patterns of tissue flow underlying the formation of the primitive streak in the chick embryo. Analysis of time-lapse sequences of brightfield images to extract the tissue velocity field and of fluorescence images of small groups of DiI-labelled cells have shown that epiblast cells move in two large-scale counter-rotating streams, which merge at the site of streak formation. Despite the large-scale tissue flows, individual cells appear to move little relative to their neighbours. As the streak forms, it elongates in both the anterior and posterior directions. Inhibition of actin polymerisation via local application of the inhibitor latrunculin A immediately terminates anterior extension of the streak tip, but does not prevent posterior elongation. Inhibition of actin polymerisation at the base of the streak completely inhibits streak formation, implying that continuous movement of cells into the base of the forming streak is crucial for extension. Analysis of cycling cells in the early embryo shows that cell-cycle progression in the epiblast is quite uniform before the primitive streak forms then decreases in the central epiblast and incipient streak and increases at the boundary between the area pellucida and area opaca during elongation. The cell-cycle inhibitor aphidicolin, at concentrations that completely block cell-cycle progression, permits initial streak formation but arrests development during extension. Our analysis suggests that cell division maintains the cell-flow pattern that supplies the streak with cells from the lateral epiblast, which is critical for epiblast expansion in peripheral areas, but that division does not drive streak formation or the observed tissue flow. Author Affiliation: (a) Department of Physics, Biocomplexity Institute, Indiana University, 727 East Third Street, Swain Hall West 159, Bloomington, IN 47405-7105, USA (b) Division of Cell and Developmental Biology, Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK Article History: Received 28 October 2004; Revised 19 February 2005; Accepted 8 April 2005

• Novel simulation method explores diffusion in bi-dispersed pores. • Study critiques Maxwell and Nield models' predictivity limits. • Modifies random pore model, boosts accuracy in low macro-porosity. The classical diffusion models fail to predict the diffusivity of bi-dispersed porous materials, particularly at low macro-porosity. In this work, a pore-scale simulation is carried out to investigate the diffusion process inside ordered and random bi-dispersed pore structures under different growth phases and shapes. The applicability of existing models is evaluated. The results reveal that Maxwell and Nield models are inadequate to predict the diffusivity of the ordered macropore structure under different growth phase types and shapes. Meanwhile, the ordered distribution of microporous spherical particles is superior to that of macropores. For random pore structure, the macropore-macropore diffusion path contributes to the error of the random pore model, which depends on the ratio of the micropore-macropore diffusivity. [ABSTRACT FROM AUTHOR]

Coal-assisted water electrolysis for hydrogen production (CAWE) is a promising method for the efficient utilization of coal resources and the sustainable generation of hydrogen. However, identifying a cost-effective and efficient carbon source remains a critical and ongoing challenge. This study proposes the use of flotation tail coal as a novel and efficient carbon source for water electrolysis. Through a combination of electrochemical experiments, thermodynamic analysis, and comprehensive material characterization techniques, this research explores the effectiveness of tail coal-assisted water electrolysis for hydrogen production (TCAWE) in enhancing hydrogen production efficiency. It is found that the catalytic effect of minerals, particularly iron and manganese ions, is instrumental in significantly reducing energy consumption and enhancing the anodic oxidation reactions in the CAWE process. Flotation tail coal, with its high content of these catalytic minerals and favorable hydrophilic surface properties, not only lowers the electrolysis voltage but also increases the hydrogen yield compared to traditional coal sources. This research innovatively demonstrates that utilizing flotation tail coal in water electrolysis offers a dual benefit: it provides a cost-effective, abundant carbon source while promoting a more efficient and sustainable hydrogen production process. Additionally, this approach is expected to facilitate the resource utilization of waste flotation tail coal. [Display omitted] • Tail coal outperforms raw and concentrate coal in electrolysis and Tafel slope. • Fe³⁺ reduces energy consumption through enhanced anodic oxidation. • Hydrophilicity and minerals improve dispersion and catalytic interaction. [ABSTRACT FROM AUTHOR]

Over years, there has been a widespread quest for effective dietary patterns and natural extracts to mitigate prostate cancer risk. However, despite numerous experimental studies conducted on various natural extracts, the evidence substantiating their efficacy remains largely insufficient. This dearth of compelling evidence presents a significant challenge in advocating for their widespread use as preventive measures against prostate cancer. Our study endeavors to undertake a network meta-analysis to evaluate the influence of natural extracts on prostate cancer. Researchers systematically searched through Embase, PubMed, Cochrane Library, and Web of Science databases until December 2023. The main focus was on assessing primary outcomes comprising prostate-specific antigen (PSA), insulin-like growth factor-binding protein-3 (IGFBP-3), insulin-like growth factor-1 (IGF-1). We conducted data analysis utilizing StataMP 15.0 software. Therapeutic effects were ranked based on the probability values derived from Surface Under the Cumulative Ranking curve (SUCRA). Additionally, cluster analysis was employed to assess the impacts of natural extracts on three distinct outcomes. Following screening procedures, the 28 eligible studies were incorporated, the selected studies encompassed 1,566 prostate cancer patients and evaluated 16 different natural extract treatments. Specifically, 24 trials included PSA indicators, 10 included IGF-1 indicators, and 8 included IGFBP-3 indicators. The findings revealed that, based on the SUCRA values, the combined therapy of silybin with selenium (74%) appears to be the most effective approach for reducing serum PSA levels. Simultaneously, silybin alone (84.6%) stands out as the most promising option for decreasing serum IGF-1 levels. Lastly, concerning IGFBP-3, silybin alone (67.7%) emerges as the optimal choice. Twelve studies provided comprehensive information on adverse drug reactions/events (ADR/ADE), whereas five articles did not report any significant ADR/ADE. The NMA suggests that, compared to placebo, utilizing silybin either alone or in combination with selenium has been shown to enhance therapeutic effects, offering potential benefits to patients with prostate cancer. This study can offer valuable insights for prostate patients considering natural extract treatments. Further evidence is required to confirm the safety profile of these treatments. [ABSTRACT FROM AUTHOR]

Gestational diabetes could elevate the risk of congenital heart defects (CHD) in infants, and effective preventive and therapeutic medications are currently lacking. Atractylenolide-I (AT-I) is the active ingredient of Atractylodes Macrocephala Koidz (known as Baizhu in China), which is a traditional pregnancy-supporting Chinese herb. In this study, we investigated the protective effect of AT-I on the development of CHD in embryos exposed to high glucose (HG). First, systematic review search results revealed associations between gestational diabetes mellitus (GDM) and cardiovascular malformations. Subsequently, a second systematic review indicated that heart malformations were consistently associated with oxidative stress and cell apoptosis. We assessed the cytotoxic impacts of Atractylenolide compounds (AT-I, AT-II, and AT-III) on H9c2 cells and chick embryos, determining an optimal concentration of AT-I for further investigation. Second, immunofluorescence, western blot, Polymerase Chain Reaction (PCR), and flow cytometry were utilized to delve into the mechanisms through which AT-I mitigates oxidative stress and apoptosis in cardiac cells. Molecular docking was employed to investigate whether AT-I exerts cardioprotective effects via the STAT3 pathway. Then, we developed a streptozotocin-induced diabetes mellitus (PGDM) mouse model to evaluate AT-I's protective efficacy in mammals. Finally, we explored how AT-I protects hyperglycemia-induced abnormal fetal heart development through microbiota analysis and untargeted metabolomics analysis. The study showed the protective effect of AT-I on embryonic development using a chick embryo model which rescued the increase in the reactive oxygen species (ROS) and decrease in cell survival induced by HG. We also provided evidence suggesting that AT-I might directly interact with STAT3, inhibiting its phosphorylation. Further, in the PGDM mouse model, we observed that AT-I not only partially alleviated PGDM-related blood glucose issues and complications but also mitigated hyperglycemia-induced abnormal fetal heart development in pregnant mice. This effect is hypothesized to be mediated through alterations in gut microbiota composition. We proposed that dysregulation in microbiota metabolism could influence the downstream STAT3 signaling pathway via EGFR, consequently impacting cardiac development and formation. This study marks the first documented instance of AT-I's effectiveness in reducing the risk of early cardiac developmental anomalies in fetuses affected by gestational diabetes. AT-I achieves this by inhibiting the STAT3 pathway activated by ROS during gestational diabetes, significantly reducing the risk of fetal cardiac abnormalities. Notably, AT-I also indirectly safeguards normal fetal cardiac development by influencing the maternal gut microbiota and suppressing the EGFR/STAT3 pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

• Systematic literature reviews suggested the anti-tumor potentials of reversine. • Reversine inhibited the growth of osteosarcoma cell xenograft in vivo. • Reversine inhibited osteosarcoma cells proliferation. • Reversine induced osteosarcoma cell apoptosis. • Reversine inhibited osteosarcoma cell migration. • MEK1 is an effective target for reversine to inhibit the growth of osteosarcoma. Reversine, or 2-(4-morpholinoanilino)-6-cyclohexylaminopurine, is a 2,6-disubstituted purine derivative. This small molecule shows anti-tumor potential by playing a central role in the inhibition of several kinases related to cell cycle regulation and cytokinesis. In this study, systematic review demonstrated the feasibility and pharmacological mechanism of anti-tumor effect of reversine. Firstly, we grafted MNNG/HOS, U-2 OS, MG-63 osteosarcoma cell aggregates onto chicken embryonic chorioallantoic membrane (CAM) to examine the tumor volume of these grafts after reversine treatment. Following culture, reversine inhibited the growth of osteosarcoma cell aggregates on CAM significantly. In vitro experiment, reversine suppressed osteosarcoma cell viability, colony formation, proliferation, and induced apoptosis and cell cycle arrest at G 0 -G 1 phase. Scratch wound assay demonstrated that reversine restrained cell migration. Reversine increased the protein expression of E-cadherin. The mRNA expression of Rac1, RhoA, CDC42, PTK2, PXN, N-cadherin, Vimentin in MNNG/HOS, U-2 OS and MG-63 cells were suppressed and PTEN increased after reversine treatment. Network pharmacology prediction, molecular docking and systematic review revealed MEK1 can be used as an effective target for reversine to inhibit osteosarcoma. Western blot results show the regulation of MEK1 and ERK1/2 by reversine was not consistent in different osteosarcoma cell lines, but we found that reversine significantly inhibited the protein expression of MEK1 in MNNG/HOS, U-2 OS and MG-63. All these suggested that reversine can exert its anti-tumor effect by targeting the expression of MEK1. [ABSTRACT FROM AUTHOR]

In order to improve the hydrogen production efficiency by glycerol steam reforming, a membrane-assisted fluidized bed reactor with carbon dioxide sorption is developed to enhance the reforming process. Low-temperature operation in a membrane reactor is necessary considering the thermal stability of membrane. In this work, the sorption-enhanced glycerol steam reforming process in a fluidized bed membrane reactor under the condition of low temperature is numerically investigated, where the hydrotalcite is employed as CO 2 sorbents. The impact of operating pressure on the reforming performance is further evaluated. The results demonstrate that the integration of membrane hydrogen separation and CO 2 sorption can effectively enhance the low-temperature glycerol reforming performance. The fuel conversion above 95% can be achieved under an elevated pressure. • Low-temperature glycerol reforming is investigated considering membrane stability. • Fuel conversion above 95% is achieved under high pressure condition. • Capacity of hydrotalcite as low-temperature sorbents is examined. • Concentration polarization by membrane separation in a fluidized bed is analyzed. [ABSTRACT FROM AUTHOR]

In this work, a three-dimensional simulation of the sorption-enhanced glycerol reforming (SEGR) process for hydrogen production in a membrane-assisted fluidized bed reactor is carried out by means of the multi-fluid model coupling with chemical kinetics model and membrane separation model. The mutual interaction mechanism of the two enhancing methods including membrane hydrogen separation and carbon dioxide sorption is revealed. The results indicate that the carbon dioxide sorption can hinder the concentration polarization resistance and improve the hydrogen permeation rate while the scope of densified zones is enlarged. Meanwhile, the increase of hydrogen separation degree is also beneficial to the carbon dioxide sorption performance. In addition, the utilization of bi-functional sorbent-catalyst particles can further promote the sorption-enhanced reforming process compared to the conventional two-pellet design. • SEGR process in a membrane-assisted fluidized bed reactor is simulated. • Impact of carbon dioxide sorption on concentration polarization is examined. • Capability of bi-functional catalyst-sorbent particles is evaluated. • Effect of membrane parameters on SEGR process is analyzed. [ABSTRACT FROM AUTHOR]

A fluidized bed membrane reactor has its great advantage in the industrial application of hydrogen production owing to good mass and heat transfer characteristics compared to a fixed bed membrane reactor. However, the concentration polarization and the densification zone formation caused by membrane permeation will restrict mass and heat transfer as well as hydrogen membrane flux. In this work, a three-dimensional simulation is carried out to investigate the hydrogen separation process in a fluidized bed membrane reactor under the Euler-Euler framework. The effects of membrane arrangements with different eccentric distances and membrane sites including internal and external membranes on concentration polarization and densification zones are discussed. The results reveal that the enhancement of eccentric distances can weaken the concentration polarization, whereas the densification zone scope is enhanced. The arrangement of internal membranes can hinder the concentration polarization and promote the hydrogen separation, while external membranes significantly influence the hydrogen removal at the bottom of the reactor. • Hydrogen separation in a fluidized bed membrane reactor is numerically studied. • Effect of membrane arrangement with different eccentric distance is evaluated. • Concentration polarization with internal and external membrane is compared. [ABSTRACT FROM AUTHOR]

2-Amino-1-methyl-6-phenylimidazo [4,5-b] pyrimidine (PhIP) is a known carcinogen generated mainly from cooking meat and environmental pollutants. It is worth exploring the potential of natural small-molecule drugs to protect against adverse effects on embryonic development. In this study, we investigated the potential toxicological effects of PhIP on embryonic heart tube formation and the effect of Sulforaphane (SFN) administration on the anti-toxicological effects of PhIP on embryonic cardiogenesis. First, the chicken embryo model was used to investigate the different phenotypes of embryonic heart tubes induced by various concentrations of PhIP exposure. We also proved that SFN rescues PhIP-induced embryonic heart tube malformation. Second, immunofluorescence, western blot, Polymerase Chain Reaction (PCR) and flow cytometry experiments were employed to explore the mechanisms by which SFN protects cardiac cells from oxidative damage in the presence of PhIP. We used RNA-seq analysis, molecular docking, in situ hybridization, cellular thermal shift assay and solution nuclear magnetic resonance spectroscopy to explore whether SFN protects cardiogenesis through the EGFR/MAPK signaling pathway. The study showed that PhIP might dose-dependently interfere with the C-looping heart tube (mild) or the fusion of a pair of bilateral endocardial tubes (severe) in chick embryos, while SFN administration prevented cardiac cells from oxidative damage in the presence of high-level PhIP. Furthermore, we found that excessive reactive oxygen species (ROS) production and subsequent apoptosis were not the principal mechanisms by which low-level PhIP induced malformation of heart tubes. This is due to PhIP-disturbed Mitogen-activated protein kinase (MAPK) signaling pathway could be corrected by SFN administration. This study provided novel insight that PhIP exposure could increase the risk of abnormalities in early cardiogenesis and that SFN could partially rescue various concentrations of PhIP-induced abnormal heart tube formation by targeting EGFR and mediating EGFR/MAPK signaling pathways. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Membrane hydrogen separation can effectively promote fuel conversion and hydrogen yield by means of altering chemical equilibrium of reforming reactions. In this work, the enhancing process of glycerol steam reforming via a fluidized bed membrane reactor is numerically investigated. Under the framework of the Euler-Euler method, chemical kinetic model is implemented and the reforming performance with and without membrane separation is compared. The effect of densified zones caused by membrane separation is examined. Meanwhile, the impacts of operating parameters including hydrogen partial pressure on the permeate side and fuel gas velocity on densified zones and hydrogen yield are evaluated. The results demonstrate that the excessive reduction of hydrogen partial pressure on the permeate side and the increase of feed gas velocity are detrimental to fuel conversion and hydrogen yield. Highlights • Enhancement of glycerol reforming via a fluidized bed membrane reactor is studied. • Effect of densified zones formation on reforming performance is evaluated. • Influence of operating parameters on membrane enhancing effects is investigated. [ABSTRACT FROM AUTHOR]

In order to investigate the hydrogen separation enhancing effect on glycerol steam reforming performance, the simulation is carried out via a packed bed membrane reactor, where the porous media model is employed to model the distribution of catalyst and the non-isothermal environment in the reactor is considered. The reforming performances with and without membranes are compared. The results indicate that the membrane separation can promote the hydrogen production at a low temperature. The impacts of operating parameters including catalyst load, fuel gas temperature, sweep gas velocity and sweep gas temperature on the enhancement of the reforming performance are analyzed. The results reveal that the membrane separation is very sensitive to the temperature variation under different operating conditions. It is essential to properly control the operating parameter so as to achieve the promotion of hydrogen yield with low cost of energy. [ABSTRACT FROM AUTHOR]

The sorption-enhanced glycerol reforming performance in a fluidized bed reactor is numerically studied with CaO and Li 4 SiO 4 as CO 2 sorbents, where the multi-fluid model with the kinetic theory of granular flow is employed to carry out three-dimensional simulations. The ethanol is treated as the impurity in the crude glycerol and its effect on the reforming performance is evaluated. It is found that the hydrogen yield is higher using the crude glycerol with the ethanol owing to a greater reaction rate of the ethanol. An increase of the temperature is beneficial to the glycerol conversion and hydrogen production. Meanwhile, the enhancing effect on the reforming performance of CaO and Li 4 SiO 4 is compared. The result demonstrates that the enhancing reforming effect of the Li 4 SiO 4 -based sorbent is similar to that of the CaO-based sorbent. At a high temperature, the CaO-based sorbent has a better performance. [ABSTRACT FROM AUTHOR]

The sorption-enhanced glycerol steam reforming (SE-GSR) provides a promising high-efficient means for hydrogen production. Fluidized bed reactors have their own potential on the heat transfer and sorbent regeneration. To gain a deep insight into the SE-GSR process in fluidized bed reactors, a computational fluid dynamics (CFD) approach is employed in this study. The multi-fluid model is implemented with chemical kinetics of glycerol steam reforming and CO 2 absorption. The bubble effect on gas-solid drag force is considered via a bubble-based EMMS drag model. A three-dimensional simulation is carried out to investigate the flow characteristics and interaction mechanic of binary mixture with catalyst and sorbent particles. The predictions with and without sorption reactions are compared. The effects of operating velocity and sorbent size on the performance are also discussed. The results reveal that reducing operating velocity and sorbent diameter can improve the hydrogen yield and fuel conversion. [ABSTRACT FROM AUTHOR]

• Macroscopic continuous-microscopic discrete model is applied to porous particles. • Flow and mass transfer characteristics of porous particles are investigated. • Effect of gas permeation and circumfluence of porous particles is analyzed. The gas permeation effect leads to a significant change of flow and mass transfer characteristics inside a porous particle, which is difficult to be explained by the conventional theory of nonporous particles. In this paper, a combined macroscopic continuous-microscopic discrete model is established for a porous particle. Flow and mass transfer characteristics of a porous particle under steady and transient flow conditions are evaluated. The microscopic pore structure, permeability and transport characteristics of a porous particle are analyzed. The results show that the critical macro-porosity exists between 0.6 and 0.7 under the competition of gas permeation and circumfluence, which influences the dominant mechanism of microscopic and macroscopic forces. Under the transient flow condition, the gas permeation and circumfluence results in the occurrence of double frequency of surface friction drag coefficient and body pressure drag coefficient as well as mass transfer coefficient. [ABSTRACT FROM AUTHOR]

• Pore-scale model is implemented for double slip effect at permeable interface. • Gas rarefaction effect on velocity slip and thermal slip is evaluated. • Influence of pore size and porosity on mass/heat transfer is revealed. The double slip effect plays an important role in transport characteristics at the permeable porous interface between porous catalytic particle and free fluid, especially for coke deposition process. In this work, a direct pore-scale simulation is carried out via lattice Boltzmann method to investigate the mass, momentum and heat transfer process inside a porous composite system. The spatial distribution of velocity and temperature under the gas rarefaction effect is analyzed. Meanwhile, the impact of coke deposition on the double slip effect is also revealed. The results reveal that a high gas rarefaction effect can weaken the velocity double slip, which are greatly influenced by pore structural parameters. The dynamic evolution of pore structure, flow and heat transfer characteristics of the porous interface during the coke deposition process is investigated. It is found that the heat flow bifurcation phenomenon is enhanced under a high gas rarefaction effect. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) are widely present in the interstitial tissue of embryos. Although the existence of the metanephros stromal stem cell population has been demonstrated, the focus has been on understanding the process of nephrogenesis, but the biological characterization of stromal stem cell population is less precise. Metanephric mesenchymal stem cells (MMSCs) have a vast potential in kidney tissue engineering and represent excellent candidates in cellular replacement therapy for human disease and veterinary research. Here, we aimed to isolate, culture, and characterize bovine MMSCs. We have successfully obtained a new population of stem cells using renal tissue isolated from three-month-old bovine embryo. MMSCs were isolated by collagenase digestion. The spindle-shaped cells adhered to plastic and exhibited extensive proliferation for more than 26 passages and good clonogenic ability in vitro. Moreover, the metanephric mesenchymal stem cells could be induced to differentiate into mesoderm-derived cells (such as osteoblasts, chondrocytes, and adipocytes) and endoderm-derived hepatocyte-like cells in vitro. These results indicated the multiple differentiations potential of MMSCs. Aside from colony-forming, self-renewal, and multilineage differentiation capabilities, the experiments of immunofluorescence and RT-PCR showed that spindle-shaped cells were positive for MSCs-related markers (CD29, CD44, CD73, CD90, CD106), nestin and vimentin, while the hematopoietic cell surface markers CD34 and pan-leukocyte marker CD45 were undetectable. This study provides a technical platform for the preservation of valuable bovine genetic resources and offers a new source for tissue engineering and cell transplantation therapy. • Isolating and charactering metanephric mesenchymal stem cells for the first time from fetal bovine kidney. • Verifying that bovine metanephric mesenchymal stem cells have stable proliferation ability in vitro. • Confirming that bovine metanephric mesenchymal stem cells have multi-directional differentiation potential. [ABSTRACT FROM AUTHOR]

Introduction: For ectopic tubal pregnancy to be viable, it requires a supporting vascular network and functioning trophoblast. Slit2/Robo1 signaling plays an important role in placental angiogenesis during normal pregnancy. Hence, we here investigated whether or not Slit2/Robo1 signaling also had an impact in ectopic tubal pregnancy.Methods: The Slit2 and Robo1 expression pattern relevant to trophoblast invasive behavior and vascular remodeling was studied in human tubal placenta obtained from patients with ectopic pregnancy (5-8weeks gestation), The trophoblast development, vascular architecture and Robo1 expression pattern were observed in Slit2 overexpression (Slit2-Tg) and C57BL mice placenta (E13.5 and E15.5).Results: Marked with CK-7 and Vimentin, the vessel profiles of fallopian tube were classified into four stages. In the presence of extravillous trophoblast (EVT), stellate-shaped and polygonal-shaped EVTs were observed, and the stellate-shaped EVT showed the higher Slit2 expression (P < 0.01) but lower Robo1 expression (P < 0.05) than polygonal-shaped cells. By contrast, a temporary Slit2 up-regulation in remodeling vessel and Slit2 down-regulation in remodeled vessel of polygonal-shape extravillous trophoblast cells occurred in tubal pregnancies. In Slit2-Tg mice E13.5 and E15.5 placenta, Slit2 overexpression promoted vascular remodeling by increasing in the diameter of the maternal blood sinusoids and fetal capillaries, but enhanced the thickness of trophoblast and vasculature at E15.5 Slit2-Tg mice.Conclusions: The varying Slit2 and Robo1 expression in EVTs was associated with trophoblast invasion and probably plays an important role in the events of blood vessel remodeling of the fallopian tube tissues. [ABSTRACT FROM AUTHOR]

Many human disorders induce high salinity in tissues and organs, interfering with their normal physiological functions. Using a mouse model, we demonstrated that high salt intake caused infertility. Specifically, we established that high salinity dramatically affects ovarian follicle development and the extent of follicular atresia. However, it did not significantly influence the primordial follicles. TUNEL assays revealed that high salt intake inhibited follicle development by inducing the granulosa and theca cells that surround the oocytes to undergo apoptosis. Furthermore, immunohistological staining for the proliferation markers Ki67 and PH3 showed that high salt intake also repressed granulosa cell proliferation. In vitro testing of granulosa cells also confirmed that high salt significantly repressed cell proliferation and promoted cell apoptosis. In summary, high salt consumption negatively impacts reproductive functions in female mice by interfering with ovarian folliculogenesis. [ABSTRACT FROM AUTHOR]

Catalytic reforming technology is regarded as one of the most popular hydrogen production methods. The introduction of a fluidized bed reactor provides a promising opportunity for the enhancement of catalytic reforming technology owing to its good gas-solid contact as well as heat and mass transfer characteristics. In order to improve the hydrogen production, the strengthening method of reforming technology via hydrogen membrane separation has been developed in the last years. In this paper, the development and challenge of catalytic reforming technology using a membrane-assisted fluidized bed for hydrogen production are reviewed. Some influencing factors of membrane separation such as membrane material, membrane sealing, carbon monoxide poisoning, membrane pollution and membrane arrangement are summarized. Meanwhile, some features of a fluidized bed membrane reactor such as sweep gas effect, bubble-to-emulsion mass transfer, densified zone formation and concentration polarization are reviewed. Some coupling technologies including the integration of hydrogen permeation and carbon dioxide sorption technology as well as the combination of hydrogen separation and oxygen introduction are also introduced. • Catalytic reforming using a membrane-assisted fluidized bed is reviewed. • Influencing factors of membrane separation are summarized. • Coupling of membrane separation and other technologies is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Fucosyltransferase IV is an essential enzyme that catalyzes the synthesis of fucosylated oligosaccharides by transferring GDP-fucose to the terminal N-acetylglucosamine with the α1,3-linkage. Lewis Y oligosaccharide has a terminal α1,3-linked fucose residue and elevation of Lewis Y level is seen in many epithelial cancers. The mechanism of Lewis Y elevation in neoplastic cells is still largely unknown. To study the impact of fucosyltransferase IV on Lewis Y expression and its role on neoplastic cell proliferation, a pEGFP-N1-FUT4 recombinant plasmid was developed and stably transfected into A431 cells. We found that fucosyltransferase IV overexpression promoted cell proliferation and increased the expression of proliferating cell nuclear antigen that correlated with Lewis Y augmentation. Cell cycle analysis demonstrated that fucosyltransferase IV overexpression facilitated cell cycle progression. In conclusion, fucosyltransferase IV overexpression augments Lewis Y expression to trigger neoplastic cell proliferation. These studies suggest that fucosyltransferase IV may serve as a potential therapeutic target for the treatment of Lewis Y-positive epithelial cancers. [Copyright &y& Elsevier]

Abstract: To evaluate the association between the expression of human macrophage metalloelastase (matrix metalloproteinase-12, MMP-12) with cancer invasion and differentiation of endometrial adenocarcinoma, specimens from endometrial adenocarcinoma (n=61) of diverse stages and histologic types were collected from patients having undergone hysterectomy, and specimens from normal endometrium (n=38) were obtained from patients with benign diseases. The expression of MMP-12 was analyzed immunohistochemically, by Western blot, and RT-PCR. The positive rate of MMP-12 was significantly increased in endometrial adenocarcinoma (81.97%) as compared with that in normal endometrium (13.16%). The results showed that expression of MMP-12 correlated with stage (p=0.022) and grade (p=0.018) of endometrial cancer. MMP-12 immunoreactive proteins were found mainly on the glandular epithelial cells of endometrial adenocarcinoma. The macrophage infiltration detected by CD68 immunohistochemical staining in endometrial adenocarcinoma was also higher than that in normal endometrium. In this study, we show that in addition to macrophages, endometrial adenocarcinoma cells are able to express MMP-12. Increased MMP-12 expression tended to be associated with the extent of adenocarcinoma invasion accompanied by marked macrophage infiltration. Our results suggest that MMP-12 is an important oncogene in high-stage and high-grade endometrial adenocarcinoma. [Copyright &y& Elsevier]

During gastrulation in amniotes, epiblast cells ingress through the primitive streak and migrate away to form endodermal, mesodermal, and extraembryonic structures. Here we analyze the detailed movement trajectories of cells emerging at different anterior-posterior positions from the primitive streak, using in vivo imaging of the movement of GFP-tagged streak cells. Cells emerging at different anterior-posterior positions from the streak show characteristic cell migration patterns, in response to guidance signals from neighboring tissues. Streak cells are attracted by sources of FGF4 and repelled by sources of FGF8. The observed movement patterns of anterior streak cells can be explained by an FGF8-mediated chemorepulsion of cells away from the streak followed by chemoattraction toward an FGF4 signal produced by the forming notochord. [Copyright &y& Elsevier]

• LF-NMR and ERM was used to evaluated the pore connectivity of cement slurry; • First quantitative analysis of the pore connectivity in early hydration of cement slurry; • Pore connectivity of oil-well cement slurry in the first 20 h was studied; • Formation of chain C-S-H rapidly decreased the pore connectivity of cement slurry. The pore connectivity of cement slurry is an important parameter to be considered when investigating short-term gas migration in the cementing engineering of natural gas wells. This study combined electrical resistivity measurements (ERM), low-field nuclear magnetic resonance, and multi-phase phenomenological models to create an in situ evaluation method for the pore connectivity of cement slurry. This method was effective for investigating the porosity, pore size, and pore connectivity of the cement slurry in the early hydration stage. The results showed that the initial formation factor of the cement slurry was determined by the water-to-cement ratio (w/c). In the initial hydration stage, the porosity of the cement slurry (w/c = 0.44) was approximately 58%. Additionally, the pore size ranged from 11 to 75 nm, and the pore connectivity was 0.65–0.70. The small amount of Q1 calcium silicate hydrate (C-S-H) generated during the hydration induction period did not affect the dispersed-particle microstructure of the cement slurry and had little effect on its pore structure. During the hydration acceleration period, numerous Q1 and Q2 SiO 4 species were detected, which converted the microstructure of the cement slurry to a cross-linked structure, thereby reducing the pore size and pore connectivity of the cement slurry. The porosity of the cement slurry reduced to 52% after hydration for 12 h at 30 °C. However, the pore size distribution decreased to 4.5–35 nm, and the pore connectivity varied from 0.5 to 0.58. [ABSTRACT FROM AUTHOR]

• Coke deposition in a single particle and a packed reactor is simulated. • Catalyst deactivation mechanism of heterogeneous type particles is revealed. • Mass and heat transfer of egg-shell and egg-yolk type catalyst is compared. Coke deposition over catalytic particles is not only associated with pore structure and pore distribution, but also depends on the active component distribution. A particle-resolved model is employed to explore the coke deposition process inside catalyst particles with heterogeneous active component distribution. The spatial and instantaneous distribution of coke deposition and its influence on catalytic performance in a single particle and a packed bed are evaluated. The results show that there is a weaker internal resistance of mass and heat transfer inside the egg-shell type catalyst so as to lead to a faster coke accumulation and catalyst deactivation, compared to the egg-yolk type catalyst. Meanwhile, the wall effect on coke accumulation is more significant for egg-yolk type catalysts. [ABSTRACT FROM AUTHOR]