A novel filtration system for point of care washing of cellular therapy products

The cell therapy industry would greatly benefit from a simple point of care solution to remove Dimethyl Sulfoxide (DMSO) from small volume thawed cell suspensions prior to injection. We have designed and validated a novel dead-end filtration device, which takes advantage of the higher density of thawed cell suspensions to remove the DMSO and protein impurities from the cell suspension without fouling the filter membrane. The filter was designed to avoid fluid circuits and minimize the surface area that is contacted by the cell suspension, thus reducing cell losses by design. The filtration process was established through optimization of the fluid flow configuration, backflush cycles and filter geometry. Overall, this novel filtration device allows for a 1 mL of thawed cryopreserved cell suspensions, containing 107 cells of a foetal lung fibroblast cell line (MRC-5), to be washed in less than 30 minutes. More than 95% of the DMSO and up to 94% of the Albumin- Fluorescein-Isothiocyanate content can be removed while the viable cell recovery is higher than 80%. We have also demonstrated that this system can be used for bone marrow-derived human mesenchymal stem cells with more than 73% cell recovery and 85% DMSO reduction. This is the first time that a dead end (normal) filtration process has been used to successfully wash high density human cell suspensions. In practice, this novel solid-liquid separation technology fills the need for small volume washing in closed processing systems for cellular therapies

A Unified Scaling Law in Spiral Galaxies

We investigate the origin of a unified scaling relation in spiral galaxies. Observed spiral galaxies are spread on a plane in the three-dimensionallogarithmic space of luminosity L, radius R and rotation velocity V. The plane is expressed as $L \propto (V R)^{\alpha}$ in I-passband, where $\alpha$ is a constant. On the plane, observed galaxies are distributed in an elongated region which looks like the shape of a surfboard. The well-known scaling relations, L-V (Tully-Fisher relation), V-R (also the Tully-Fisher relation) and R-L (Freeman's law), can be understood as oblique projections of the surfboard-like plane into 2-D spaces. This unified interpretation of the known scaling relations should be a clue to understand the physical origin of all the relations consistently. Furthermore, this interpretation can also explain why previous studies could not find any correlation between TF residuals and radius. In order to clarify the origin of this plane, we simulate formation and evolution of spiral galaxies with the N-body/SPH method, including cooling, star formation and stellar feedback. Initial conditions are set to isolated 14 spheres with two free parameters, such as mass and angular momentum. The CDM (h=0.5, $\Omega_0=1$) cosmology is considered as a test case. The simulations provide the following two conclusions: (a) The slope of the plane is well reproduced but the zero-point is not. This zero-point discrepancy could be solved in a low density ($\Omega_00.5) cosmology. (b) The surfboard-shaped plane can be explained by the control of galactic mass and angular momentum.Comment: Accepted for publication in ApJ Letters. 6 pages including 2 figure

Urine plasmin-like substances as an index of kidney allograft rejections.

Using solid state radioimmunoassays developed by the first author, changes in the urine level of plasmin-like substances (PLS) and fibrin degradation products (FDP) before and after human kidney transplantation were determined in 49 transplant patients. Averages of urine PLS and FDP in a normal population of 51 persons were 0.13+/-0.10 (SD) and 0.14+/-0.07 microng/ml, respectively. In all transplant patients there was an initial rise of both PLS and FDP in urine immediately after transplantation. This elevation peaked on days 4 and 5 and the PLS and FDP levels returned to normal range within 2 weeks in patients without evidence of rejeciton. A secondary rise of urine PLS was detected before or with a rise in serum creatinine in all of the patients experiencing rejections. Of 11 patients who showed a rejection episode within 2 weeks of transplantation, the secondary rise of urine PLS was detectable in 55% of the patients slightly before the serum creatinine level changes; of 6 patients with a rejection episode more than 2 weeks after transplantation, 100% showed a secondary PLS rise 6.7+/-2.3 (SE) days before the serum creatinine increased. The appearance of the secondary rise of urine FDP in the rejecting recipients was slightly later than the rise of PLS. Serial determination of urine PLS levels following human kidney transplantation appears to be an early index of rejections which occurs more than 2 weeks after transplantation, although the clinical usefulness of this measurement is probably limited

The Detailed Star Formation History in the Spheroid, Outer Disk, and Tidal Stream of the Andromeda Galaxy

Using the Advanced Camera for Surveys on the Hubble Space Telescope, we have obtained deep optical images reaching stars well below the oldest main sequence turnoff in the spheroid, tidal stream, and outer disk of the Andromeda Galaxy. We have reconstructed the star formation history in these fields by comparing their color-magnitude diagrams to a grid of isochrones calibrated to Galactic globular clusters observed in the same bands. Each field exhibits an extended star formation history, with many stars younger than 10 Gyr but few younger than 4 Gyr. Considered together, the star counts, kinematics, and population characteristics of the spheroid argue against some explanations for its intermediate-age, metal-rich population, such as a significant contribution from stars residing in the disk or a chance intersection with the stream's orbit. Instead, it is likely that this population is intrinsic to the inner spheroid, whose highly-disturbed structure is clearly distinct from the pressure-supported metal-poor halo that dominates farther from the galaxy's center. The stream and spheroid populations are similar, but not identical, with the stream's mean age being ~1 Gyr younger; this similarity suggests that the inner spheroid is largely polluted by material stripped from either the stream's progenitor or similar objects. The disk population is considerably younger and more metal-rich than the stream and spheroid populations, but not as young as the thin disk population of the solar neighborhood; instead, the outer disk of Andromeda is dominated by stars of age 4 - 8 Gyr, resembling the Milky Way's thick disk. The disk data are inconsistent with a population dominated by ages older than 10 Gyr, and in fact do not require any stars older than 10 Gyr.Comment: Accepted for publication in The Astrophysical Journal. 29 pages, 23 figures (including 9 in color), latex. Updated for minor edits and additional references. Images and CMDs are significantly smoothed and degraded in this version; a version with high-quality figures is available at http://www.stsci.edu/~tbrown/m31sfh/preprint.pd

The cosmological origin of the Tully-Fisher relation

We use high-resolution cosmological simulations that include the effects of gasdynamics and star formation to investigate the origin of the Tully-Fisher relation in the standard Cold Dark Matter cosmogony. Luminosities are computed for each model galaxy using their full star formation histories and the latest spectrophotometric models. We find that at z=0 the stellar mass of model galaxies is proportional to the total baryonic mass within the virial radius of their surrounding halos. Circular velocity then correlates tightly with the total luminosity of the galaxy, reflecting the equivalence between mass and circular velocity of systems identified in a cosmological context. The slope of the relation steepens slightly from the red to the blue bandpasses, and is in fairly good agreement with observations. Its scatter is small, decreasing from \~0.45 mag in the U-band to ~0.34 mag in the K-band. The particular cosmological model we explore here seems unable to account for the zero-point of the correlation. Model galaxies are too faint at z=0 (by about two magnitudes) if the circular velocity at the edge of the luminous galaxy is used as an estimator of the rotation speed. The Tully-Fisher relation is brighter in the past, by about ~0.7 magnitudes in the B-band at z=1, at odds with recent observations of z~1 galaxies. We conclude that the slope and tightness of the Tully-Fisher relation can be naturally explained in hierarchical models but that its normalization and evolution depend strongly on the star formation algorithm chosen and on the cosmological parameters that determine the universal baryon fraction and the time of assembly of galaxies of different mass.Comment: 5 pages, 4 figures included, submitted to ApJ (Letters

A multi-discpilnary training programme for end-of-life care: a sequential simulation

Sequential Simulation,1 a longitudinal form of simulation, was identified as an effective training approach for multi-disciplinary teams in identifying and caring for patients in their last year of life in a hospital setting. Sequential Simulation is a physical simulation of a pathway of care rather than isolated components of the trajectory. End-of-life care for patients in hospital has been reported as inadequate in the UK.2 The need for this training was identified through the literature and an in-house training needs analysis in conjunction with patients and their families

Conseil-santé dans la médecine de premier recours, partie 2

Les maladies non transmissibles (MNT, en anglais «non-communicable diseases») ont gagné du terrain dans le monde entier. Les approches de conseil fourni au cabinet médical ont déjà été présentées dans un premier article. Le présent article se consacre aux conditions permettant à ces approches de déployer leur efficacité au niveau de la population. Ceci est illustré sur la base des programmes suisses actuels «Vivre sans tabac», PAPRICA et «Coaching Santé» ainsi que de l’exemple historique «Ça débouche sur quoi?»

The Real Symplectic Groups in Quantum Mechanics and Optics

text of abstract (We present a utilitarian review of the family of matrix groups $Sp(2n,\Re)$, in a form suited to various applications both in optics and quantum mechanics. We contrast these groups and their geometry with the much more familiar Euclidean and unitary geometries. Both the properties of finite group elements and of the Lie algebra are studied, and special attention is paid to the so-called unitary metaplectic representation of $Sp(2n,\Re)$. Global decomposition theorems, interesting subgroups and their generators are described. Turning to $n$-mode quantum systems, we define and study their variance matrices in general states, the implications of the Heisenberg uncertainty principles, and develop a U(n)-invariant squeezing criterion. The particular properties of Wigner distributions and Gaussian pure state wavefunctions under $Sp(2n,\Re)$ action are delineated.)Comment: Review article 43 pages, revtex, no figures, replaced because somefonts were giving problem in autometic ps generatio

Magnetic properties of the low-dimensional spin-1/2 magnet \alpha-Cu_2As_2O_7

In this work we study the interplay between the crystal structure and magnetism of the pyroarsenate \alpha-Cu_2As_2O_7 by means of magnetization, heat capacity, electron spin resonance and nuclear magnetic resonance measurements as well as density functional theory (DFT) calculations and quantum Monte Carlo (QMC) simulations. The data reveal that the magnetic Cu-O chains in the crystal structure represent a realization of a quasi-one dimensional (1D) coupled alternating spin-1/2 Heisenberg chain model with relevant pathways through non-magnetic AsO_4 tetrahedra. Owing to residual 3D interactions antiferromagnetic long range ordering at T_N\simeq10K takes place. Application of external magnetic field B along the magnetically easy axis induces the transition to a spin-flop phase at B_{SF}~1.7T (2K). The experimental data suggest that substantial quantum spin fluctuations take place at low magnetic fields in the ordered state. DFT calculations confirm the quasi-one-dimensional nature of the spin lattice, with the leading coupling J_1 within the structural dimers. QMC fits to the magnetic susceptibility evaluate J_1=164K, the weaker intrachain coupling J'_1/J_1 = 0.55, and the effective interchain coupling J_{ic1}/J_1 = 0.20.Comment: Accepted for publication in Physical Review