24 research outputs found
Multimodal imaging of hair follicle bulge-derived stem cells in a mouse model of traumatic brain injury
Traumatic brain injury (TBI) is a devastating event for which current therapies are limited. Stem cell transplantation may lead to recovery of function via different mechanisms, such as cell replacement through differentiation, stimulation of angiogenesis and support to the microenvironment. Adult hair follicle bulge-derived stem cells (HFBSCs) possess neuronal differentiation capacity, are easy to harvest and are relatively immune-privileged, which makes them potential candidates for autologous stem cell-based therapy. In this study, we apply in vivo multimodal, optical and magnetic resonance imaging techniques to investigate the behavior of mouse HFBSCs in a mouse model of TBI. HFBSCs expressed Luc2 and copGFP and were examined for their differentiation capacity in vitro. Subsequently, transduced HFBSCs, preloaded with ferumoxytol, were transplanted next to the TBI lesion (cortical region) in nude mice, 2Â days after injury. Brains were fixed for immunohistochemistry 58Â days after transplantation. Luc2- and copGFP-expressing, ferumoxytol-loaded HFBSCs showed adequate neuronal differentiation potential in vitro. Bioluminescence of the lesioned brain revealed survival of HFBSCs and magnetic resonance imaging identified their localization in the area of transplantation. Immunohistochemistry showed that transplanted cells stained for nestin and neurofilament protein (NF-Pan). Cells also expressed laminin and fibronectin but extracellular matrix masses were not detected. After 58Â days, ferumoxytol could be detected in HFBSCs in brain tissue sections. These results show that HFBSCs are able to survive after brain transplantation and suggest that ce
Comparison of some Reduced Representation Approximations
In the field of numerical approximation, specialists considering highly
complex problems have recently proposed various ways to simplify their
underlying problems. In this field, depending on the problem they were tackling
and the community that are at work, different approaches have been developed
with some success and have even gained some maturity, the applications can now
be applied to information analysis or for numerical simulation of PDE's. At
this point, a crossed analysis and effort for understanding the similarities
and the differences between these approaches that found their starting points
in different backgrounds is of interest. It is the purpose of this paper to
contribute to this effort by comparing some constructive reduced
representations of complex functions. We present here in full details the
Adaptive Cross Approximation (ACA) and the Empirical Interpolation Method (EIM)
together with other approaches that enter in the same category
The Sudbury Neutrino Observatory
The Sudbury Neutrino Observatory is a second generation water Cherenkov
detector designed to determine whether the currently observed solar neutrino
deficit is a result of neutrino oscillations. The detector is unique in its use
of D2O as a detection medium, permitting it to make a solar model-independent
test of the neutrino oscillation hypothesis by comparison of the charged- and
neutral-current interaction rates. In this paper the physical properties,
construction, and preliminary operation of the Sudbury Neutrino Observatory are
described. Data and predicted operating parameters are provided whenever
possible.Comment: 58 pages, 12 figures, submitted to Nucl. Inst. Meth. Uses elsart and
epsf style files. For additional information about SNO see
http://www.sno.phy.queensu.ca . This version has some new reference
Supplementary Material for: Adaptation of the Score for Allergic Rhinitis in the Chinese Population: Psychometric Properties and Diagnostic Accuracy
<i>Background:</i> Allergic rhinitis (AR) is a worldwide health problem with rising prevalence. To enhance the estimation of AR prevalence in epidemiological studies, the Score for AR (SFAR), a screening tool, has been developed and widely used. An 8-item SFAR is a handy, self-administered instrument assessing the information on nasal and eye symptoms, seasonal increase in symptoms, skin test results, and previous AR diagnoses. This study aimed to adapt the SFAR to the Chinese population (CSFAR) and validate it by testing its psychometric properties and diagnostic accuracy. <i>Methods:</i>This methodological study involved translation and validation phases. Different batches of participants were recruited for the above purposes. <i>Results:</i> In phase 1, the CSFAR obtained satisfactory item (80-100%) and scale level (97.8%) semantic equivalence, content validity index (96.7%), comprehensibility (100%), cross-language testing (κ = 0.44-0.83 for item-to-item agreement; intraclass correlation coefficient [ICC] = 0.95, <i>p</i> < 0.05-0.001). In phase 2, CSFAR showed satisfactory internal consistency (α = 0.83), 1-month (ICC = 0.88) and 1-year stability (ICC = 0.85), and construct validity (significant correlation between CSFAR and impairments induced by AR: <i>r</i> = 0.47, <i>p</i> < 0.001). Based on the receiver-operating characteristic curve, comparing the CSFAR with diagnosis made by specialists, an optimal cutoff value was 6 (sensitivity 81.8% and specificity 80.3%). <i>Conclusion:</i> SFAR was translated into a Chinese version, the CSFAR. Satisfactory results were obtained for its equivalence, appropriateness, comprehensibility, and relevance, as well as its reliability and validity. A cutoff value of 6 was recommended to increase the diagnostic accuracy in environments with less pollen. This study provides evidence that the SFAR we adapted for the Chinese population is a valuable tool in AR screening