7 research outputs found
Power asymmetry in CMB polarization maps from PLANCK : a local variance analysis
A persistent signal of power asymmetry on opposite hemispheres of CMB sky was
seen in full-sky temperature measurements made so far. This asymmetry was seen
in microwave sky from WMAP as well as PLANCK satellites, and calls for
attention the larger question of \emph{statistical isotropy}, one of the
foundational principles of modern cosmology. In this work we present an
analysis of polarized CMB maps from PLANCK 2015 full mission data. We apply the
local variance estimator on low resolution mode maps from PLANCK 2015
polarization \texttt{Commander} solution. We find a significant hemispherical
power asymmetry in polarization data on large angular scales, at the level of
depending on the galactic mask, and the circular disc radius
used for computing local variance maps. However the direction is found to be
pointing broadly towards CMB kinetic dipole direction. Precise measurements of
CMB polarization in future will shed light on this apparent discrepancy in the
anisotropy axis seen in temperature and polarized CMB sky, and likely influence
of systematics on our findings.Comment: 21 pages, 10 figures, 3 table
Heart Repair Using Nanogel-Encapsulated Human Cardiac Stem Cells in Mice and Pigs with Myocardial Infarction
Stem
cell transplantation is currently implemented clinically but
is limited by low retention and engraftment of transplanted cells
and the adverse effects of inflammation and immunoreaction when allogeneic
or xenogeneic cells are used. Here, we demonstrate the safety and
efficacy of encapsulating human cardiac stem cells (hCSCs) in thermosensitive
poly(<i>N</i>-isopropylacrylamine-<i>co</i>-acrylic
acid) or P(NIPAM-AA) nanogel in mouse and pig models of myocardial
infarction (MI). Unlike xenogeneic hCSCs injected in saline, injection
of nanogel-encapsulated hCSCs does not elicit systemic inflammation
or local T cell infiltrations in immunocompetent mice. In mice and
pigs with acute MI, injection of encapsulated hCSCs preserves cardiac
function and reduces scar sizes, whereas injection of hCSCs in saline
has an adverse effect on heart healing. In conclusion, thermosensitive
nanogels can be used as a stem cell carrier: the porous and convoluted
inner structure allows nutrient, oxygen, and secretion diffusion but
can prevent the stem cells from being attacked by immune cells
Inflammatory response in the two MI models.
<p>(A-C): Representative fluorescent micrographs showing the presence of CD68<sup>+</sup> macrophages (green) in the hearts of SHAM (A), SMI (B), and CMI (C) groups. (D): Quantitation of CD68<sup>+</sup> macrophages in each group at Day 21 (n = 3). <b>Cell apoptosis in the two MI models.</b> (E-G): Representative fluorescent micrographs showing the presence of TUNEL<sup>+</sup> apoptotic cells (red) in the hearts of SHAM (E), SMI (F), and CMI (G) groups. (H): Quantitation of TUNEL<sup>+</sup> cells (red) in each group at Day 21 (n = 3). Scale bars = 100 um. * indicates <i>P</i><0.05 when compared to SHAM group; NS indicates <i>P</i>>0.05 when compared to each other.</p
Surgical clip for LAD ligation.
<p>(A) & (B): Pictures showing the surgical clip dispenser and its tip containing the metal clip; (C) & (D): Schematic and gross heart picture showing left anterior descending artery (LAD) ligation by a surgical clip.</p
Short-term and long-term infarct sizes in the two MI models.
<p>(A): Representative photographs of TTC-stained heart sections obtained from SHAM, SMI and CMI groups at 24 hours after surgery, yellow arrow indicated infarcted area. (B) Representative micrographs of H & E stained heart sections obtained from SHAM, SMI and CMI groups at 21 day after surgery. (C) Representative micrographs of Masson’s trichrome stained heart sections obtained from SHAM, SMI and CMI groups at 21 day after surgery. (D) Quantitative analysis of infarct sizes from the Masson’s trichrome images (n = 6 animals per group). * indicates <i>P</i> < 0.05 when compared to SHAM; NS indicates <i>P</i>>0.05 when compared to each other.</p
Total surgical time and LAD ligation time.
<p>(A): Total surgical time for the AMI model in SHAM (black bar), SMI (blue bar) and CMI (red bar) groups (n = 6); (B): Time required for left anterior descending artery (LAD) ligation in SMI (blue bar) and CMI (red bar) groups (n = 6). <b>Survival rates in the two MI models.</b> (C): Mice were subjected to SHAM or myocardial infarction (MI) surgery with either suture method or clip method and 4 hour perisurgery survival rate was recorded. (D): Long-term (21 day) survival rate. <b>Cardiac functions in the two MI models measured by echocardiography.</b> (E): Representative echocardiograph showing wall motion in SHAM, SMI and CMI groups at 21 day. (F & G): Left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) were measured by echocardiography at baseline (4 h post-MI) and 21 days afterward in SHAM, SMI and CMI groups (n = 6 animals per group). * indicates <i>P</i><0.05 when compared to SHAM group; <sup>#</sup> indicates <i>P</i><0.05 when compared to SMI group; NS indicates <i>P</i>>0.05 when compared to each other.</p
Various stages of clip method.
<p>(A): Placing the unconscious mouse on a warm pad and shaving in the area of the precordial chest; (B): A small skin cut was made in the middle position of precordial chest; (C): a purse suture was made; (D) Dissecting and retracting the pectoral major and minor muscle to expose the 4th intercostal space; (E): Placing the mosquito clamp at the 4th intercostal space with the help of forceps; (F): Forcing the mosquito to open the pleural membrane and pericardium at the 4th intercostal space; (G) & (H): With the clamp slightly open and finger strength, the heart was smoothly and gently “popped out” through the window; (I)–(K): Once the LAD was located, an automatic clip applier was used to dispense a clip to ligate the LAD with a ~60–90 degree angle along the heart long axis; (L): Placing the heart back in to the intra-thoracic space promptly after ligation, therewith manual evacuation of air and closure of muscle and the skin by the pre-placed purse-string suture.</p