Search results for "Phase separation"

PLLA Scaffold via TIPS for Bone Tissue Engineering

2016

Tissue engineering offers a promising new approach to repair bone fractures, fractures that do not heal, and fractures due to bone tumors. In this work, two different approaches were tested in order to obtain Poly-L- Lactic Acid (PLLA) porous scaffolds via Thermally Induced Phase Separation (TIPS) for bone tissue engineering application. First, the possibility to produce a composite material, by incorporating Hydroxyapatite (HA) particles in a Poly-L-lactic acid (PLLA) matrix was investigated. Two PLLA/HA weight ratios (70/30 and 50/50) were tested. The results showed that the presence of HA does not influence the phase separation process, i.e. the composite scaffolds microstructure is simi…

3 ′-5 ′ crosstalk contributes to transcriptional bursting

2019

Abstract Background Transcription in mammalian cells is a complex stochastic process involving shuttling of polymerase between genes and phase-separated liquid condensates. It occurs in bursts, which results in vastly different numbers of an mRNA species in isogenic cell populations. Several factors contributing to transcriptional bursting have been identified, usually classified as intrinsic, in other words local to single genes, or extrinsic, relating to the macroscopic state of the cell. However, some possible contributors have not been explored yet. Here, we focus on processes at the 3 ′ and 5 ′ ends of a gene that enable reinitiation of transcription upon termination. Results Using Bay…

The cell nucleus. A study in Burgundy

2019

ABSTRACT Wilhelm Bernhard’s revolutionary microscopy techniques helped him put forward the hypothesis of specialized compartmentalization of the nucleus. He also described for the first time the nuclear bodies and peri-chromatin fibrils, and demonstrated that these granules contain an RNA component. The tradition of biennial workshops, named after this great scientist, continues, and this year it took place in the heart of Burgundy, in Dijon, France (May 20–24, 2019, organized by INSERM UMR1231, UBFC), where well-fed participants emphasized the importance of viewing the cell nucleus as a hub of specialized colloidal compartments that orchestrate replication, transcription and nuclear transp…

Exploring Bioequivalence of Dexketoprofen Trometamol Drug Products with the Gastrointestinal Simulator (GIS) and Precipitation Pathways Analyses

2019

The present work aimed to explain the differences in oral performance in fasted humans who were categorized into groups based on the three different drug product formulations of dexketoprofen trometamol (DKT) salt&mdash

Micelles in Mixtures of Sodium Dodecyl Sulfate and a Bolaform Surfactant

2006

Mixtures composed of water, sodium dodecyl sulfate (SDS), and a bolaform surfactant with two aza-crown ethers as polar headgroups (termed Bola C-16) were investigated by modulating the mole ratios between the components. The two surfactants have ionic and nonionic, but ionizable, headgroups, respectively. The ionization is due to the complexation of alkali ions by the aza-crown ether unit(s). Structural, thermodynamic, and transport properties of the above mixtures were investigated. Results from surface tension, translational self-diffusion, and small angle neutron scattering ( SANS) are reported and discussed. Interactions between the two surfactants to form mixed micelles result in a com…

CLOUD POINT MEASUREMENTS IN MEMBRANE FORMING SYSTEMS

2012

Temperature influence on the morphology of porous structures prepared via Thermally Induced Phase Separation (TIPS)

2013

A survey on models for the prediction of phase equilibria in polymer solutions

2011

Modeling and experimental approaches for the characterization of phase equilibria in polymer solutions

2012

Calculation of ternary polymer solution phase diagram via compressible lattice fluid model extended to specific interactions

2012

Ternary polymer solutions are currently employed for the production of porous structures (e.g. membranes and scaffolds for tissue engineering) via liquid-liquid phase separation techniques. The relation between processing conditions and thermodynamic features of the considered polymeric system determines the morphology of the as-prepared membrane. Therefore, in order to achieve a better control on a porous structure, a deep characterization of the phase behavior of a polymer solution is needed. The experimental derivation of phase diagrams is highly cost and time consuming, thus usually the cloud point curves of the system are directly measured. In this work, the compressible lattice fluid …