Molecules,
Journal Year:
2023,
Volume and Issue:
28(24), P. 8006 - 8006
Published: Dec. 8, 2023
Experimental
studies
of
the
degradation
two
ribonucleosides
(guanosine
and
uridine)
were
carried
out
by
making
use
mechanochemistry.
Mechanochemical
experiments
reveal
decomposition
guanosine
uridine,
promoted
nickel(II)
carbonate
ions,
into
guanine
uracil,
respectively.
These
nucleobases
identified
HPLC
1H
NMR
spectroscopy
(this
applied
only
to
uracil).
Additionally,
density-functional
theory
(DFT)
methodologies
used
probe
energetic
viability
several
pathways,
including
in
presence
abovementioned
ions.
Three
mechanisms
analysed
via
ribose
ring-opening:
dry,
single-molecule
water-assisted,
metal-assisted,
wherein
last
confirmed
mechanochemical
both
respective
nucleobase
moieties.
results
can
contribute
an
astrobiological
interpretation
extraterrestrial
sample's
contents.
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: June 19, 2024
Synthetic
extracellular
matrix
(ECM)
mimics
that
can
recapitulate
the
complex
biochemical
and
mechanical
nature
of
native
tissues
are
needed
for
advanced
models
development
disease.
Biomedical
research
has
heavily
relied
on
use
animal-derived
biomaterials,
which
is
now
impeding
their
translational
potential
convoluting
biological
insights
gleaned
from
in
vitro
tissue
models.
Natural
hydrogels
have
long
served
as
a
convenient
effective
cell
culture
tool,
but
advances
materials
chemistry
fabrication
techniques
present
promising
new
avenues
creating
xenogenic-free
ECM
substitutes
appropriate
organotypic
microphysiological
systems.
However,
significant
challenges
remain
synthetic
matrices
approximate
structural
sophistication,
complexity,
dynamic
functionality
tissues.
This
review
summarizes
key
properties
ECM,
discusses
recent
approaches
used
to
systematically
decouple
tune
these
matrices.
The
importance
mechanics,
such
viscoelasticity
plasticity,
also
discussed,
particularly
within
context
organoid
engineered
Emerging
design
strategies
mimic
reviewed,
multi-network
hydrogels,
supramolecular
chemistry,
assembled
monomers.
npj Aging,
Journal Year:
2024,
Volume and Issue:
10(1)
Published: June 15, 2024
Abstract
The
world
population
is
increasingly
aging,
deeply
affecting
our
society
by
challenging
healthcare
systems
and
presenting
an
economic
burden,
thus
turning
the
spotlight
on
aging-related
diseases:
exempli
gratia,
osteoporosis,
a
silent
disease
until
you
suddenly
break
bone.
increase
in
bone
fracture
risk
with
age
generally
associated
loss
of
mass
alteration
skeletal
architecture.
However,
such
changes
cannot
fully
explain
increased
fragility
age.
To
successfully
tackle
age-related
diseases,
it
paramount
to
comprehensively
understand
fundamental
mechanisms
responsible
for
tissue
degeneration.
Aging
persist
at
multiple
length
scales
within
complex
hierarchical
structure,
raising
need
multiscale
multidisciplinary
approach
resolve
them.
This
paper
aims
provide
overarching
analysis
aging
processes
review
most
prominent
outcomes
aging.
A
systematic
description
different
scales,
highlighting
corresponding
techniques
adopted
each
scale
motivating
combining
diverse
techniques,
provided
get
comprehensive
multi-physics
phenomena
involved.
Nature Communications,
Journal Year:
2023,
Volume and Issue:
14(1)
Published: April 12, 2023
Collagen
is
a
force-bearing,
hierarchical
structural
protein
important
to
all
connective
tissue.
In
tendon
collagen,
high
load
even
below
macroscopic
failure
level
creates
mechanoradicals
by
homolytic
bond
scission,
similar
polymers.
The
location
and
type
of
initial
rupture
sites
critically
decide
on
both
the
mechanical
chemical
impact
these
micro-ruptures
tissue,
but
are
yet
be
explored.
We
here
use
scale-bridging
simulations
supported
gel
electrophoresis
mass
spectrometry
determine
breakage
points
in
collagen.
find
collagen
crosslinks,
as
opposed
backbone,
harbor
weakest
bonds,
with
one
particular
trivalent
crosslinks
most
dominant
site.
identify
this
sacrificial,
rupturing
prior
other
bonds
while
maintaining
material's
integrity.
Also,
collagen's
weak
funnel
ruptures
such
that
potentially
harmful
readily
stabilized.
Our
results
suggest
unique
mode
tailored
towards
combatting
an
early
onset
material
ageing.
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 8, 2025
Structural
tissues
like
tendon
are
subjected
to
repeated
tensile
strains
in
vivo
and
excessive
cause
irreversible
changes
the
tissue.
Large
affect
molecular
structure
organization
of
extracellular
matrix,
these
parameters
that
drive
cell
behavior,
including
tissue
repair.
Here
we
describe
a
method
perform
solid-state
NMR
spectroscopy
on
situ
strained
samples
under
magic-angle
spinning
achieve
high-resolution
spectra
while
maintaining
tissue's
native
hydration
state.
The
observed
interpreted
using
quantum
mechanics
(QM/MM)
chemical
shift
calculations
collagen
triple-helix
structures
consideration
distribution
orientations
between
relaxed
mechanical
states.
We
demonstrate
our
strain
combination
with
spectral
simulations
can
detect
tendons
loaded
plastic
deformation
subsequent
structural
relaxation
unloaded
Clinical Orthopaedics and Related Research,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 18, 2025
Background
Peripheral
nerve
injury
commonly
results
in
long-term
disability
and
pain
for
patients.
Recovery
after
traction
or
crush
is
unpredictable
depends
on
the
degree
of
injury.
Our
inability
to
accurately
assess
severity
hampers
our
ability
predict
chances
recovery
need
surgical
intervention
form
neurolysis,
repair,
graft.
An
investigation
into
histologic
sequence
mechanics
failure
under
tension
may
help
process
assessing
injury,
prognosis
recovery,
treatment.
Questions/purposes
Using
an
vivo
rat
model,
we
asked:
(1)
What
pattern
mechanical
during
stretch?
(2)
Is
there
staggered
disintegration
specific
anatomic
substructures
when
occurs?
Methods
To
answer
first
research
question
about
stretch,
four
12-month-old
male
Sprague-Dawley
rats
were
enrolled
a
load-to-failure
experiment
generating
load-deformation
curves
median
nerve.
Under
anesthesia,
nerves
both
forelimbs
surgically
exposed
secured
two
blunt
metal
pins
1
cm
apart.
A
hook
was
attached
load-cell
raised
from
beneath
at
speed
0.2
mm/second
until
complete
rupture
occurred.
Applied
forces
monitored
real
time
via
force-time
curve.
All
experiments
filmed,
euthanized
afterward.
Based
experiments,
identified
distinct
events
sudden
force
reduction
stretching
curve
We
labeled
these
as
epineuroclasis
second
endoneuroclasis.
Neuroclasis
derives
Greek
term
“neuron”
nerve,
suffix
“-clasis”
means
breaking
fracture.
additional
eight
used
investigate
whether
this
caused
by
anatomical
substructures.
left
stretched
point
right
endoneuroclasis
point.
Induction
confirmed
load-time
curves,
held
place
5
minutes
before
released.
Nerve
function
assessed
using
handheld
electrical
stimulator.
The
harvested
histology
(to
integrity
epineurium,
axons
intraneural
vasculature,
endoneurial
collagen
[dis-]organization,
well
molecular
damage),
immediately
after.
uninjured
control
tissue.
Mechanical,
functional,
findings
compared
between
levels
with
nerves.
Results
Load-to-failure
revealed
characteristic
that
occurred
mean
±
SD
resistance
2.3
0.5
N
1.4
(mean
difference
0.9
0.6
[95%
confidence
interval
0.4
1.4];
p
=
0.003),
respectively.
Additional
investigating
points
(epineuroclasis)
associated
epineurium
plastic
deformation
fibers,
whereas
(endoneuroclasis)
tubes,
axons,
vasculature.
Epineuroclasis
severely
impaired
conductivity
(median
stimulation
25
nC
[range
50
nC]
preinjury
170
300
epineuroclasis,
medians
145
nC;
<
0.001).
Endoneuroclasis
induced
even
greater
functional
impairment
than
400
2000
endoneuroclasis,
230
0.005).
Both
could
be
through
live
analysis
stretch.
Conclusion
injuries
follow
structural
failure,
preceding
transection.
Clinical
Relevance
order
seems
predictable
“outside-in”
pattern.
This
inform
classification
system
stretch
more
reflect
pathoanatomy
prognosis.
offer
new
based
rats.
However,
future
studies
are
needed
validate
applicability
neuroclasis
human
peripheral
clinical
implementation
use
can
proposed.
characterization
animal
model
provides
framework
facilitate
development
novel
diagnostic
tools,
potentially
identifying
changes
found
study
acute
setting.
Journal of the mechanical behavior of biomedical materials/Journal of mechanical behavior of biomedical materials,
Journal Year:
2024,
Volume and Issue:
159, P. 106697 - 106697
Published: Aug. 23, 2024
The
mineralized
collagen
fibril
is
the
main
building
block
of
hard
tissues
and
it
directly
affects
macroscopic
mechanics
biological
such
as
bone.
mechanical
behavior
itself
determined
by
its
structure:
content
molecules,
minerals,
cross-links,
interactions
properties
these
components.
Advanced
glycation
end
products
(AGEs)
form
cross-links
between
tropocollagen
molecules
within
are
one
important
factor
that
believed
to
have
a
major
influence
on
tissue.
For
instance,
has
been
shown
brittleness
in
bone
correlates
with
increased
AGEs
densities.
However,
underlying
nano-scale
mechanisms
remain
unknown.
Here,
we
study
effect
mineral
cross-linking
deformation
fracture
performing
destructive
tensile
tests
using
coarse-grained
molecular
dynamics
simulations.
Our
results
demonstrate
after
exceeding
critical
mineral,
induces
stiffening
at
high
strain
levels.
We
show
morphology
location
affect
mechanics:
which
this
occurs
depends
mineral's
morphology.
Further,
both,
increasing
density
lead
peak
stresses.
At
low
contents,
response
dominated
AGEs,
while
determines
mechanics.
Chemical Communications,
Journal Year:
2024,
Volume and Issue:
60(77), P. 10629 - 10641
Published: Jan. 1, 2024
Large
or
repeated
mechanical
loads
degrade
polymeric
materials
by
accelerating
chain
fragmentation.
This
mechanochemical
backbone
fracture
usually
occurs
homolysis
of
otherwise
inert
C-C,
C-O
and
C-S
bonds,
generating
highly
reactive
macroradicals.
Because
is
detrimental
on
its
own
the
resulting
macroradicals
can
initiate
damaging
reaction
cascades,
a
major
thrust
in
contemporary
polymer
mechanochemistry
to
suppress
it,
release
"hidden
length"
that
dissipates
local
molecular
strain.
Here
we
summarize
an
emerging
complementary
strategy
channelling
mechanochemically
generated
cascades
form
new
load-bearing
chemical
which
enables
self-healing
self-strengthening,
and/or
generate
mechanofluorescence,
could
yield
detailed
quantitative
understanding
how
material-failure-inducing
macroscopic
distribute
across
network.
We
aim
identify
generalizable
lessons
derivable
from
reported
implementations
this
outline
key
challenges
adapting
it
diverse
loading
scenarios.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(24)
Published: April 3, 2023
Abstract
Here
we
uncover
collagen,
the
main
structural
protein
of
all
connective
tissues,
as
a
redox‐active
material.
We
identify
dihydroxyphenylalanine
(DOPA)
residues,
post‐translational
oxidation
products
tyrosine
to
be
common
in
collagen
derived
from
different
tissues.
observe
that
these
DOPA
residues
endow
with
substantial
radical
scavenging
capacity.
When
reducing
radicals,
work
redox
relay:
they
convert
quinone
and
generate
hydrogen
peroxide.
In
this
dual
function,
outcompetes
its
amino
acid
precursors
ascorbic
acid.
Our
results
establish
side
chains
collagens,
probably
protecting
tissues
against
radicals
formed
under
mechanical
stress
and/or
inflammation.