Mesenchymal stem cell secretes microparticles enriched in pre-microRNAs

10.1093/nar/gkp857Nucleic Acids Research381215-22

Long-term microcarrier suspension cultures of human embryonic stem cells

AbstractThe conventional method of culturing human embryonic stem cells (hESC) is on two-dimensional (2D) surfaces, which is not amenable for scale up to therapeutic quantities in bioreactors. We have developed a facile and robust method for maintaining undifferentiated hESC in three-dimensional (3D) suspension cultures on matrigel-coated microcarriers achieving 2- to 4-fold higher cell densities than those in 2D colony cultures. Stable, continuous propagation of two hESC lines on microcarriers has been demonstrated in conditioned media for 6 months. Microcarrier cultures (MC) were also demonstrated in two serum-free defined media (StemPro and mTeSR1). MC achieved even higher cell concentrations in suspension spinner flasks, thus opening the prospect of propagation in controlled bioreactors

The quantitative proteomes of human-induced pluripotent stem cells and embryonic stem cells

An in-depth proteomic comparison of human-induced pluripotent stem cells, and their parent fibroblast cells, with embryonic stem cells shows that the reprogramming process comprehensively remodels protein expression levels, creating cells that closely resemble natural stem cells

Fast and Facile Synthesis Route to Epitaxial Oxide Membrane Using a Sacrificial Layer

The advancement in thin-film exfoliation for synthesizing oxide membranes has opened up new possibilities for creating artificially-assembled heterostructures with structurally and chemically incompatible materials. The sacrificial layer method is a promising approach to exfoliate as-grown films from a compatible material system, allowing their integration with dissimilar materials. Nonetheless, the conventional sacrificial layers often possess intricate stoichiometry, thereby constraining their practicality and adaptability, particularly when considering techniques like Molecular Beam Epitaxy (MBE). This is where easy-to-grow binary alkaline earth metal oxides with a rock salt crystal structure are useful. These oxides, which include (Mg, Ca, Sr, Ba)O, can be used as a sacrificial layer covering a much broader range of lattice parameters compared to conventional sacrificial layers and are easily dissolvable in deionized water. In this study, we show the epitaxial growth of single-crystalline perovskite SrTiO3 (STO) on sacrificial layers consisting of crystalline SrO, BaO, and Ba1-xCaxO films, employing a hybrid MBE method. Our results highlight the rapid (< 5 minutes) dissolution of the sacrificial layer when immersed in deionized water, facilitating the fabrication of millimeter-sized STO membranes. Using high-resolution x-ray diffraction, atomic-force microscopy, scanning transmission electron microscopy, impedance spectroscopy, and scattering-type near-field optical microscopy (SNOM), we demonstrate epitaxial STO membranes with bulk-like intrinsic dielectric properties. The employment of alkaline earth metal oxides as sacrificial layers is likely to simplify membrane synthesis, particularly with MBE, thus expanding research possibilities.Comment: 36 pages, 4 figure

Tyrosine phosphorylation profiling in FGF-2 stimulated human embryonic stem cells

10.1371/journal.pone.0017538PLoS ONE63

Enabling a robust scalable manufacturing process for therapeutic exosomes through oncogenic immortalization of human ESC-derived MSCs

10.1186/1479-5876-9-47Journal of Translational Medicine9

Development of Bead Modelling for Distortion Analysis Induced by Wire Arc Additive Manufacturing using FEM and Experiment

In this research, Wire Arc Additive Manufacturing is modelled and simulated to determine the most suitable bead modelling strategy. This analysis is aimed to predict distortion by means of thermomechanical Finite Element Method (FEM). The product model with wire as feedstock on plate as substrate and process simulation are designed in form of multi-layered beads and single string using MSC Marc/Mentat. This research begins with finding suitable WAAM parameters which takes into account the bead quality. This is done by using robotic welding system with 01.2mm filler wire (AWS A5.28 : ER80SNi1), shielding gas (80% Ar/ 20% CO2) and 6mm-thick low carbon steel as base plate. Further, modelling as well as simulation are to be conducted with regards to bead spreading of each layers. Two different geometrical modelling regarding the weld bead are modelled which are arc and rectangular shape. Equivalent material properties from database and previous researches are implemented into simulation to ensure a realistic resemblance. It is shown that bead modelling with rectangular shape exhibits faster computational time with less error percentage on distortion result compared to arc shape. Moreover, by using the rectangular shape, the element and meshing are much easier to be designed rather than arc shape bead

A flow-based multi-agent data exfiltration detection architecture for ultra-low latency networks

This is an accepted manuscript of an article published by ACM in ACM Transactions on Internet Technology on 16/07/2021, available online: https://dl.acm.org/doi/10.1145/3419103 The accepted version of the publication may differ from the final published version.Modern network infrastructures host converged applications that demand rapid elasticity of services, increased security and ultra-fast reaction times. The Tactile Internet promises to facilitate the delivery of these services while enabling new economies of scale for high-fdelity of machine-to-machine and human-to-machine interactions. Unavoidably, critical mission systems served by the Tactile Internet manifest high-demands not only for high speed and reliable communications but equally, the ability to rapidly identify and mitigate threats and vulnerabilities. This paper proposes a novel Multi-Agent Data Exfltration Detector Architecture (MADEX) inspired by the mechanisms and features present in the human immune system. MADEX seeks to identify data exfltration activities performed by evasive and stealthy malware that hides malicious trafc from an infected host in low-latency networks. Our approach uses cross-network trafc information collected by agents to efectively identify unknown illicit connections by an operating system subverted. MADEX does not require prior knowledge of the characteristics or behaviour of the malicious code or a dedicated access to a knowledge repository. We tested the performance of MADEX in terms of its capacity to handle real-time data and the sensitivity of our algorithm’s classifcation when exposed to malicious trafc. Experimental evaluation results show that MADEX achieved 99.97% sensitivity, 98.78% accuracy and an error rate of 1.21% when compared to its best rivals. We created a second version of MADEX, called MADEX level 2 that further improves its overall performance with a slight increase in computational complexity. We argue for the suitability of MADEX level 1 in non-critical environments, while MADEX level 2 can be used to avoid data exfltration in critical mission systems. To the best of our knowledge, this is the frst article in the literature that addresses the detection of rootkits real-time in an agnostic way using an artifcial immune system approach while it satisfes strict latency requirements

Human Embryonic Stem Cell Technology: Large Scale Cell Amplification and Differentiation

Embryonic stem cells (ESC) hold the promise of overcoming many diseases as potential sources of, for example, dopaminergic neural cells for Parkinson’s Disease to pancreatic islets to relieve diabetic patients of their daily insulin injections. While an embryo has the innate capacity to develop fully functional differentiated tissues; biologists are finding that it is much more complex to derive singular, pure populations of primary cells from the highly versatile ESC from this embryonic parent. Thus, a substantial investment in developing the technologies to expand and differentiate these cells is required in the next decade to move this promise into reality. In this review we document the current standard assays for characterising human ESC (hESC), the status of ‘defined’ feeder-free culture conditions for undifferentiated hESC growth, examine the quality controls that will be required to be established for monitoring their growth, review current methods for expansion and differentiation, and speculate on the possible routes of scaling up the differentiation of hESC to therapeutic quantities