arXiv (Cornell University),
Год журнала:
2023,
Номер
unknown
Опубликована: Янв. 1, 2023
Rapid
mapping
of
the
mechanical
properties
soft
biological
tissues
from
light
microscopy
to
macroscopic
imaging
could
transform
fundamental
biophysical
research
by
providing
clinical
biomarkers
complement
in
vivo
elastography.
We
here
introduce
superfast
optical
time-harmonic
elastography
(OTHE)
remotely
encode
surface
and
subsurface
shear
wave
fields
for
generating
maps
tissue
stiffness
with
unprecedented
detail
resolution.
OTHE
rigorously
exploits
space-time
propagation
characteristics
waves
address
current
limitations
biomechanical
Key
solutions
are
presented
stimulation,
encoding,
reconstruction
time-harmonic,
multifrequency
waves,
all
tuned
provide
consistent
values
across
resolutions
microns
millimeters.
OTHE's
versatility
is
demonstrated
Bacillus
subtilis
biofilms,
zebrafish
embryos,
adult
zebrafish,
human
skeletal
muscle,
reflecting
diversity
phylogenetic
tree
a
mechanics
perspective.
By
zooming
on
details
coarse
finer
scales,
advances
developmental
biology
offers
way
perform
biomechanics-based
histology
that
consistently
matches
patients.
Environmental Microbiology,
Год журнала:
2024,
Номер
26(7)
Опубликована: Июль 1, 2024
Abstract
Bacteria
are
often
found
in
environments
where
space
is
limited,
and
they
attach
themselves
to
surfaces.
One
common
form
of
movement
on
these
surfaces
bacterial
twitching
motility,
which
powered
by
the
extension
retraction
type
IV
pili.
Although
motility
unrestricted
conditions
has
been
extensively
studied,
effects
spatial
confinement
this
behaviour
not
well
understood.
In
study,
we
explored
diffusive
properties
individual
Pseudomonas
aeruginosa
cells
spatially
confined
conditions.
We
achieved
placing
bacteria
between
layers
agarose
glass,
then
tracking
long‐term
cells.
Interestingly,
that
while
reduced
immediate
speed
twitching,
it
paradoxically
increased
diffusion.
Through
a
combination
mechanical
geometrical
analysis,
as
numerical
simulations,
showed
increase
diffusion
could
be
attributed
factors.
The
constraint
imposed
altered
pattern
from
normal
superdiffusion.
These
findings
provide
valuable
insights
into
motile
environments.
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Авг. 4, 2023
Type
IV
pili
are
ancient
and
widespread
filamentous
organelles
found
in
most
bacterial
archaeal
phyla
where
they
support
a
wide
range
of
functions,
including
substrate
adhesion,
DNA
uptake,
self
aggregation,
cell
motility.
In
bacteria,
PilT-family
ATPases
disassemble
adhesion
pili,
causing
them
to
rapidly
retract
produce
twitching
motility,
important
for
surface
colonization.
As
archaea
do
not
possess
homologs
PilT,
it
was
thought
that
cannot
retract.
Here,
we
employ
live-cell
imaging
under
native
conditions
(75°C
pH
2),
together
with
automated
single-cell
tracking,
high-temperature
fluorescence
imaging,
genetic
manipulation
demonstrate
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Май 9, 2023
Bacterial
pathogenicity
relies
on
both
firm
surface
adhesion
and
cell
dissemination.
How
twitching
bacteria
resolve
the
fundamental
contradiction
between
migration
is
unknown.
To
address
this
question,
we
employ
live-cell
imaging
of
type-IV
pili
(T4P)
therewith
construct
a
comprehensive
mathematical
model
arXiv (Cornell University),
Год журнала:
2023,
Номер
unknown
Опубликована: Янв. 1, 2023
Rapid
mapping
of
the
mechanical
properties
soft
biological
tissues
from
light
microscopy
to
macroscopic
imaging
could
transform
fundamental
biophysical
research
by
providing
clinical
biomarkers
complement
in
vivo
elastography.
We
here
introduce
superfast
optical
time-harmonic
elastography
(OTHE)
remotely
encode
surface
and
subsurface
shear
wave
fields
for
generating
maps
tissue
stiffness
with
unprecedented
detail
resolution.
OTHE
rigorously
exploits
space-time
propagation
characteristics
waves
address
current
limitations
biomechanical
Key
solutions
are
presented
stimulation,
encoding,
reconstruction
time-harmonic,
multifrequency
waves,
all
tuned
provide
consistent
values
across
resolutions
microns
millimeters.
OTHE's
versatility
is
demonstrated
Bacillus
subtilis
biofilms,
zebrafish
embryos,
adult
zebrafish,
human
skeletal
muscle,
reflecting
diversity
phylogenetic
tree
a
mechanics
perspective.
By
zooming
on
details
coarse
finer
scales,
advances
developmental
biology
offers
way
perform
biomechanics-based
histology
that
consistently
matches
patients.
