To assess changes in passive mechanical properties, associated protein structure, and histology of multifidus in response to disc degeneration produced by experimental needle puncture.
Summary of Background Data. Relationships have been reported between muscle dysfunction and low back injury; however, little is known about the cause and effect of such relationships.
Methods. Twelve rabbits were studied; 4 in each
of 3 groups: control, 4-weeks postintervertebral disc injury (4-week disc degeneration), and 12-weeks KPT-8602 in vivo postintervertebral disc injury (12-week disc degeneration). Single multifidus fibers and bundles of fibers were isolated and tested for slack sarcomere length and elastic modulus. Titin isoform 3-deazaneplanocin A cost mass, myosin heavy chain distribution, and muscle histology were also examined.
Results. Compared to control, individual muscle fibers were 34% stiffer and fiber bundles 107% stiffer in the 12-week disc degeneration group. No changes were detected at 4-week disc degeneration. No statistically significant change was found for MHC distribution in the 12-week disc degeneration group when compared to control, whereas titin isoforms were larger (P < 0.05) in the 12-week disc degeneration group. Histology revealed select regions of multifidus, at 12-week disc degeneration, with increased
space between bundles of fibers, which in some instances was partly occupied by adipose tissue.
Conclusion. Multifidus becomes stiffer, both in individual fibers and fiber bundles, in response to experimentally induced intervertebral disc degeneration. This cannot be explained
by change in fiber-type due to reduced muscle use, nor by the increased size of the protein titin (which would reduce stiffness). We hypothesize that fiber bundles become stiffer by proliferation and/or reorganization of collagen content within the muscle but the basis for fiber stiffening GSK1838705A is not known.”
“Crosslinked polyacrylonitrile (PAN) was synthesized with divinylbenzene as the crosslinker with an iron(III)-mediated atom transfer radical polymerization method with activators regenerated by electron transfer. The polymerization exhibited first-order kinetics with respect to the polymerization time. Hydroxylamine hydrochloride (NH2OH.HCl) was used to modify the cyano groups of the crosslinked PAN to obtain amidoxime (AO) groups. The AO-crosslinked PAN was used to remove Hg(II). The optimum pH, adsorption kinetics, and adsorption isotherms were investigated. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012″
“A previous meta-analysis determined that the effects of steroids during sepsis were dose-dependent; since then, additional trials have been published. The current analysis updates our previous analysis examining the effects of steroids during sepsis. A literature search from 2004 to 2008 identified seven randomized controlled trials in adult patients; these were added to 14 previously identified trials.