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991.
Michelle Holthaus Nivethiha Santhakumar Thorsten Wahlers Adnana Paunel-Grgülü 《International journal of molecular sciences》2022,23(8)
The preconditioning of mesenchymal stem cells (MSCs) has been recognized as an attractive tool to improve their regenerative and immunomodulatory capacities based on their paracrine effects. In this study, we examined the potential of an MSC-conditioned medium (MSC-CM) to alter the phenotype of murine macrophages and to drive reprogramming toward an anti-inflammatory, M2-like state in vitro. We further explored the impact of MSC cytokine preconditioning on the immunosuppressive properties of the MSC secretome. The MSC-CM suppressed the expression of proinflammatory genes in murine M1 macrophages, but only the CM from preconditioned MSCs (preMSC-CM) downregulated their expression during M1 polarization. Remarkably, only the preMSC-CM significantly increased the expression of M2a-, M2b- and M2c-specific genes and proteins during M2a polarization. Further, macrophages were found to secrete high levels of anti-inflammatory IL-10. Similarly, M2a macrophages cultured in the presence of the preMSC-CM displayed an enhanced expression of M2b/M2c-specific markers, suggesting that the secretome of preMSC promotes the repolarization of M2a-like macrophages to M2b/M2c subtypes. The preMSC-CM was found to be enriched in molecules involved in M2 polarization. Additionally, a unique downregulation of extracellular matrix components was observed. Altogether, the preMSC-CM may provide an attractive strategy to dampen inflammation by suppressing the expression of proinflammatory mediators and promoting the polarization and phenotype switch of M2a cells to IL-10-secreting M2b/M2c-like macrophages. 相似文献
992.
Effects of chondrogenic and osteogenic regulatory factors on composite constructs grown using human mesenchymal stem cells, silk scaffolds and bioreactors. 下载免费PDF全文
Alexander Augst Darja Marolt Lisa E Freed Charu Vepari Lorenz Meinel Michelle Farley Robert Fajardo Nipun Patel Martha Gray David L Kaplan Gordana Vunjak-Novakovic 《Journal of the Royal Society Interface》2008,5(25):929-939
Human mesenchymal stem cells (hMSCs) isolated from bone marrow aspirates were cultured on silk scaffolds in rotating bioreactors for three weeks with either chondrogenic or osteogenic medium supplements to engineer cartilage- or bone-like tissue constructs. Osteochondral composites formed from these cartilage and bone constructs were cultured for an additional three weeks in culture medium that was supplemented with chondrogenic factors, supplemented with osteogenic factors or unsupplemented. Progression of cartilage and bone formation and the integration between the two regions were assessed by medical imaging (magnetic resonance imaging and micro-computerized tomography imaging), and by biochemical, histological and mechanical assays. During composite culture (three to six weeks), bone-like tissue formation progressed in all three media to a markedly larger extent than cartilage-like tissue formation. The integration of the constructs was most enhanced in composites cultured in chondrogenic medium. The results suggest that tissue composites with well-mineralized regions and substantially less developed cartilage regions can be generated in vitro by culturing hMSCs on silk scaffolds in bioreactors, that hMSCs have markedly higher capacity for producing engineered bone than engineered cartilage, and that chondrogenic factors play major roles at early stages of bone formation by hMSCs and in the integration of the two tissue constructs into a tissue composite. 相似文献
993.
Shawn C. Marshall Malcolm Man-Son-Hing Michel Bédard Judith Charlton Sylvain Gagnon Isabelle Gélinas Sjaan Koppel Nicol Korner-Bitensky Jim Langford Barbara Mazer Anita Myers Gary Naglie Jan Polgar Michelle M. Porter Mark Rapoport Holly Tuokko Brenda Vrkljan Andrew Woolnough 《Accident; analysis and prevention》2013
The Candrive II/Ozcandrive study, a multicentre prospective cohort study examining the predictive validity of tools for assessing fitness to drive, aims to develop an in-office screening tool that will help clinicians identify older drivers who may be unsafe to drive. This paper describes the study protocol. We are following a cohort of drivers aged ≥70 years for up to 4 years. Starting in 2009, 928 participants have been recruited in seven cities in four Canadian provinces, as well as 302 participants in two sites in Melbourne, Australia and Wellington, New Zealand. Participants underwent a comprehensive assessment at baseline and repeat the assessment yearly thereafter, as well as a brief follow-up assessment at 4 and 8 months each year. A recording device is installed in participants’ vehicles to assess driving patterns, and driving records are obtained from licensing authorities to determine the outcomes: at-fault crashes per kilometre driven and violations. To date, the protocol has been generally well adhered to, with 1230 participants, and barriers and challenges are being addressed, as necessary. The Candrive II/Ozcandrive study is unique owing to its size, duration, partnerships with Canadian, Australian and New Zealand stakeholders, and international research collaboration. 相似文献
994.
Roth David L.; Ackerman Michelle L.; Okonkwo Ozioma C.; Burgio Louis D. 《Canadian Metallurgical Quarterly》2008,23(3):567
Previous studies have suggested that 4 latent constructs (depressed affect, well-being, interpersonal problems, somatic symptoms) underlie the item responses on the Center for Epidemiological Studies Depression (CES-D) Scale. This instrument has been widely used in dementia caregiving research, but the fit of this multifactor model and the explanatory contributions of multifactor models have not been sufficiently examined for caregiving samples. The authors subjected CES-D data (N = 1,183) from the initial Resources for Enhancing Alzheimer's Caregiver Health Study to confirmatory factor analysis methods and found that the 4-factor model provided excellent fit to the observed data. Invariance analyses suggested only minimal item-loading differences across race subgroups and supported the validity of race comparisons on the latent factors. Significant race differences were found on 3 of the 4 latent factors both before and after controlling for demographic covariates. African Americans reported less depressed affect and better well-being than White caregivers, who reported better well-being and fewer interpersonal problems than Hispanic caregivers. These findings clarify and extend previous studies of race differences in depression among diverse samples of dementia caregivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Dupré Kathryne E.; Inness Michelle; Connelly Catherine E.; Barling Julian; Hoption Colette 《Canadian Metallurgical Quarterly》2006,91(5):987
Among adult employees, interpersonal injustice and abusive supervision predict aggression toward supervisors at work. The aim of this study was to assess whether similar relationships exist among teenage employees and, further, whether teenagers' reasons for working moderate these relationships. Multiple regression analyses on data from 119 teenage employees showed that financial and personal fulfillment reasons for working moderate the impact of interpersonal injustice and abusive supervision on aggression directed at workplace supervisors. These findings contribute to the understanding of workplace aggression by demonstrating that (a) teenagers engage in this workplace behavior, (b) the predictors are similar to those of adult aggression, and (c) reasons for working play a moderating role among this particular cohort. The possible long-term consequences of teenagers' use of aggression at work are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Marks Michelle A.; DeChurch Leslie A.; Mathieu John E.; Panzer Frederick J.; Alonso Alexander 《Canadian Metallurgical Quarterly》2005,90(5):964
The authors examined how networks of teams integrate their efforts to succeed collectively. They proposed that integration processes used to align efforts among multiple teams are important predictors of multiteam performance. The authors used a multiteam system (MTS) simulation to assess how both cross-team and within-team processes relate to MTS performance over multiple performance episodes that differed in terms of required interdependence levels. They found that cross-team processes predicted MTS performance beyond that accounted for by within-team processes. Further, cross-team processes were more important for MTS effectiveness when there were high cross-team interdependence demands as compared with situations in which teams could work more independently. Results are discussed in terms of extending theory and applications from teams to multiteam systems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Shaw Jason D.; Zhu Jing; Duffy Michelle K.; Scott Kristin L.; Shih Hsi-An; Susanto Ely 《Canadian Metallurgical Quarterly》2011,96(2):391
The authors develop and test theoretical extensions of the relationships of task conflict, relationship conflict, and 2 dimensions of team effectiveness (performance and team-member satisfaction) among 2 samples of work teams in Taiwan and Indonesia. Findings show that relationship conflict moderates the task conflict–team performance relationship. Specifically, the relationship is curvilinear in the shape of an inverted U when relationship conflict is low, but the relationship is linear and negative when relationship conflict is high. The results for team-member satisfaction are more equivocal, but the findings provide some evidence that relationship conflict exacerbates the negative relationship between task conflict and team-member satisfaction. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
998.
999.
Chelsea N. Fries Yaoying Wu Sean H. Kelly Michelle Wolf Nicole L. Votaw Stefan Zauscher Joel H. Collier 《Advanced materials (Deerfield Beach, Fla.)》2020,32(39):2003310
Peptide nanofibers are useful for many biological applications, including immunotherapy, tissue engineering, and drug delivery. The robust lengthwise assembly of these peptides into nanofibers is typically difficult to control, resulting in polydisperse fiber lengths and an incomplete understanding of how nanofiber length affects biological responses. Here, rationally designed capping peptides control the length of helical peptide nanofibers with unique precision. These designed peptides bind the tips of elongated nanofibers to shorten and narrow their length distributions. Demonstrating their use as immunotherapies, capped nanofibers are preferentially cross-presented by dendritic cells compared to uncapped nanofibers. Due to increased cross-presentation, these capped nanofibers trigger stronger CD8+ T-cell responses in mice than uncapped nanofibers. This strategy illustrates a means for controlling the length of supramolecular peptide nanofibers to modulate their immunogenicity in the context of immunotherapies. 相似文献
1000.
Izhar Singh Batth Shih-Bo Huang Michelle Villarreal Jingjing Gong Divya Chakravarthy Brian Keppler Sridharan Jayamohan Pawel Osmulski Jianping Xie Paul Rivas Roble Bedolla Michael A. Liss I-Tien Yeh Robert Reddick Hiroshi Miyamoto Rita Ghosh Addanki P. Kumar 《International journal of molecular sciences》2021,22(4)