40 research outputs found
Multiscale multifactorial approaches for engineering tendon substitutes
The physiology of tendons and the continuous strains experienced daily make tendons very prone to injury. Excessive and prolonged loading forces and aging also contribute to the onset and progression of tendon injuries, and conventional treatments have limited efficacy in restoring tendon biomechanics. Tissue engineering and regenerative medicine (TERM) approaches hold the promise to provide therapeutic solutions for injured or damaged tendons despite the challenging cues of tendon niche and the lack of tendon-specific factors to guide cellular responses and tackle regeneration. The roots of engineering tendon substitutes lay in multifactorial approaches from adequate stem cells sources and environmental stimuli to the construction of multiscale 3D scaffolding systems.
To achieve such advanced tendon substitutes, incremental strategies have been pursued to more closely recreate the native tendon requirements providing structural as well as physical and chemical cues combined with biochemical and mechanical stimuli to instruct cell behavior in 3D architectures, pursuing mechanically competent constructs with adequate maturation before implantation.Authors acknowledge the project âAccelerating tissue engineering and personalized medicine discoveries by the integration of key enabling nanotechnologies, marinederived biomaterials and stem cells,â supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European
Regional Development Fund (ERDF).
Authors acknowledge the H2020 Achilles Twinning Project No. 810850, and also the European
Research Council CoG MagTendon No. 772817, and the FCT Project MagTT PTDC/CTM-CTM/
29930/2017 (POCI-01-0145-FEDER-29930
A proteomic analysis of chondrogenic, osteogenic and tenogenic constructs from ageing mesenchymal stem cells
Measurement of J/Ï -pair production in pp collisions at âs = 13 TeV and study of gluon transverse-momentum dependent PDFs
The production cross-section of J/Ï pairs in proton-proton collisions at a centre-of-mass energy of âs = 13 TeV is measured using a data sample corresponding to an integrated luminosity of 4.2 fbâ1 collected by the LHCb experiment. The measurement is performed with both J/Ï mesons in the transverse momentum range 0 < pT< 14 GeV/c and rapidity range 2.0 < y < 4.5. The cross-section of this process is measured to be 16.36 ± 0.28 (stat) ± 0.88 (syst) nb. The contributions from single-parton scattering and double-parton scattering are separated based on the dependence of the cross-section on the absolute rapidity difference ây between the two J/Ï mesons. The effective cross-section of double-parton scattering is measured to be Ïeff = 13.1 ± 1.8 (stat) ± 2.3 (syst) mb. The distribution of the azimuthal angle ÏCS of one of the J/Ï mesons in the Collins-Soper frame and the pT-spectrum of the J/Ï pairs are also measured for the study of the gluon transverse-momentum dependent distributions inside protons. The extracted values of âšcos 2ÏCSâ© and âšcos 4ÏCSâ© are consistent with zero, but the presence of azimuthal asymmetry at a few percent level is allowed
Improved measurement of CP violation parameters in Bs0âJ/ÏK+Kâ decays in the vicinity of the Ï(1020) resonance
The decay-time-dependent
C
P
asymmetry in
B
0
s
â
J
/
Ï
(
â
Ό
+
Ό
â
)
K
+
K
â
decays is measured using proton-proton collision data, corresponding to an integrated luminosity of
6
â
â
fb
â
1
, collected with the LHCb detector at a center-of-mass energy of 13 TeV. Using a sample of approximately 349â000
B
0
s
signal decays with an invariant
K
+
K
â
mass in the vicinity of the
Ï
(
1020
)
resonance, the
C
P
-violating phase
Ï
s
is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the
B
0
s
â
ÂŻ
B
0
s
system,
Î
Î
s
, and the difference of the average
B
0
s
and
B
0
meson decay widths,
Î
s
â
Î
d
. The values obtained are
Ï
s
=
â
0.039
±
0.022
±
0.006
â
â
rad
,
Î
Î
s
=
0.0845
±
0.0044
±
0.0024
â
â
ps
â
1
, and
Î
s
â
Î
d
=
â
0.005
6
+
0.0013
â
0.0015
±
0.0014
â
â
ps
â
1
, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements to date and are consistent with expectations based on the Standard Model and with the previous LHCb analyses of this decay. These results are combined with previous independent LHCb measurements. The phase
Ï
s
is also measured independently for each polarization state of the
K
+
K
â
system and shows no evidence for polarization dependence
Wnt/ÎČ-catenin signaling suppresses expressions of Scx, Mkx, and Tnmd in tendon-derived cells
Assessment of essential characteristics of two different scaffolds for tendon in situ regeneration
Exploring Stem Cells and Inflammation in Tendon Repair and Regeneration
Tendon injuries are frequent and are responsible for substantial morbidity both in sports and in the workplace. Despite the endogenous mechanisms of tendon repair and regeneration, tendon healing upon injury is slow and often insufficient to restore complete biomechanics functionality.
Inflammation has a pivotal role in tendon healing and failed healing responses contribute to the progression of tendinopathies. However, the molecular and cellular mechanisms involved are poorly understood requiring further insights.
During inflammation, bioactive molecules such as cytokines secreted locally at the injury site, influence resident stem cells that contribute as modulatory agents over the niche towards homeostasis, holding great promise as therapeutic agents for tendon pathological conditions associated to unresolved inflammation and failed healing.
This review overviews the role of cytokines and resident cells, focusing on the participation of tendon stem cell population in inflammation and tendon healing upon injury and their potential action in resolution of pathological conditionsFundação para a CiĂȘncia e Tecnologia (FCT) for the doctoral grant PD/BD/128089/2016, the project NORTE-01-0145-FEDER-000021 supported by Norte Portugal Regional Operational Programme (NORTE 2020) and HORIZON 2020 under the TEAMING GRANT agreement No 739572 â The Discoveries CTRinfo:eu-repo/semantics/publishedVersio