9 research outputs found
Flow-Induced Shear Stress Primes NLRP3 Inflammasome Activation in Macrophages via Piezo1
The
NLRP3 inflammasome is a crucial component of the innate immune
system, playing a pivotal role in initiating and regulating the body’s
inflammatory response to various pathogens and cellular damage. Environmental
stimuli, such as temperature, pH level, and nutrient availability,
can influence the behavior and functions of innate immune cells, including
immune cell activity, proliferation, and cytokine production. However,
there is limited understanding regarding how mechanical forces, like
shear stress, govern the intrinsic inflammatory reaction, particularly
the activation of the NLRP3 inflammasome, and how shear stress impacts
NLRP3 inflammasome activation through its capacity to induce alterations
in gene expression and cytokine secretion. Here, we investigated how
shear stress can act as a priming signal in NLRP3 inflammasome activation
by exposing immortalized bone marrow-derived macrophages (iBMDMs)
to numerous physiologically relevant magnitudes of shear stress before
chemically inducing inflammasome activation. We demonstrated that
shear stress of large magnitudes was able to prime iBMDMs more effectively
for inflammasome activation compared to lower shear stress magnitudes,
as quantified by the percentage of cells where ASC-CFP specks formed
and IL-1β secretion, the hallmarks of inflammasome activation.
Testing this in NLRP3 and caspase-1 knockout iBMDMs showed that the
NLRP3 inflammasome was primarily primed for activation due to shear
stress exposure. Quantitative polymerase chain reaction (qPCR) and
a small-molecule inhibitor study mechanistically determined that shear
stress regulates the NLRP3 inflammasome by upregulating Piezo1, IKKβ,
and NLRP3. These findings offer insights into the mechanistic relationship
among physiological shear stresses, inflammasome activation, and their
impact on the progression of inflammatory diseases and their interconnected
pathogenesis
Effect of Electron Transporting Layer on Bismuth-Based Lead-Free Perovskite (CH<sub>3</sub>NH<sub>3</sub>)<sub>3</sub> Bi<sub>2</sub>I<sub>9</sub> for Photovoltaic Applications
Methylammonium
iodo bismuthate ((CH<sub>3</sub>NH<sub>3</sub>)<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub>) (MBI) perovskite is a promising
alternative to rapidly progressing hybrid organic–inorganic
lead perovskites because of its better stability and low toxicity
compared to lead-based perovskites. Solution-processed perovskite
fabricated by single-step spin-coating and subsequent heating produced
polycrystalline films of hybrid perovskite (CH<sub>3</sub>NH<sub>3</sub>)<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub>), whose morphology was influenced
drastically by the nature of substrates. The optical measurements
showed a strong absorption band around 500 nm. The devices made on
anatase TiO<sub>2</sub> mesoporous layer showed good performance with
current density over 0.8 mA cm<sup>–2</sup> while the devices
on brookite TiO<sub>2</sub> layer and planar (free of porous layer)
was inefficient. However, all the MBI devices were stable to ambient
conditions for more than 10 weeks
Combining Immune Checkpoint Inhibitors and Kinase-Inhibiting Supramolecular Therapeutics for Enhanced Anticancer Efficacy
A major
limitation of immune checkpoint inhibitors is that only
a small subset of patients achieve durable clinical responses. This
necessitates the development of combinatorial regimens with immunotherapy.
However, some combinations, such as MEK- or PI3K-inhibitors with a
PD1-PDL1 checkpoint inhibitor, are pharmacologically challenging to
implement. We rationalized that such combinations can be enabled using
nanoscale supramolecular targeted therapeutics, which spatially home
into tumors and exert temporally sustained inhibition of the target.
Here we describe two case studies where nanoscale MEK- and PI3K-targeting
supramolecular therapeutics were engineered using a quantum mechanical
all-atomistic simulation-based approach. The combinations of nanoscale
MEK- and PI3K-targeting supramolecular therapeutics with checkpoint
PDL1 and PD1 inhibitors exert enhanced antitumor outcome in melanoma
and breast cancers <i>in vivo</i>, respectively. Additionally,
the temporal sequence of administration impacts the outcome. The combination
of supramolecular therapeutics and immunotherapy could emerge as a
paradigm shift in the treatment of cancer
Combining Immune Checkpoint Inhibitors and Kinase-Inhibiting Supramolecular Therapeutics for Enhanced Anticancer Efficacy
A major
limitation of immune checkpoint inhibitors is that only
a small subset of patients achieve durable clinical responses. This
necessitates the development of combinatorial regimens with immunotherapy.
However, some combinations, such as MEK- or PI3K-inhibitors with a
PD1-PDL1 checkpoint inhibitor, are pharmacologically challenging to
implement. We rationalized that such combinations can be enabled using
nanoscale supramolecular targeted therapeutics, which spatially home
into tumors and exert temporally sustained inhibition of the target.
Here we describe two case studies where nanoscale MEK- and PI3K-targeting
supramolecular therapeutics were engineered using a quantum mechanical
all-atomistic simulation-based approach. The combinations of nanoscale
MEK- and PI3K-targeting supramolecular therapeutics with checkpoint
PDL1 and PD1 inhibitors exert enhanced antitumor outcome in melanoma
and breast cancers <i>in vivo</i>, respectively. Additionally,
the temporal sequence of administration impacts the outcome. The combination
of supramolecular therapeutics and immunotherapy could emerge as a
paradigm shift in the treatment of cancer
Vapor Annealing Controlled Crystal Growth and Photovoltaic Performance of Bismuth Triiodide Embedded in Mesostructured Configurations
Low
stability of organic–inorganic lead halide perovskite and toxicity
of lead (Pb) still remain a concern. Therefore, there is a constant
quest for alternative nontoxic and stable light-absorbing materials
with promising optoelectronic properties. Herein, we report about
nontoxic bismuth triiodide (BiI<sub>3</sub>) photovoltaic device prepared
using TiO<sub>2</sub> mesoporous film and spiro-OMeTAD as electron-
and hole-transporting materials, respectively. Effect of annealing
methods (e.g., thermal annealing (TA), solvent vapor annealing (SVA),
and Petri dish covered recycled vapor annealing (PR-VA)) and different
annealing temperatures (90, 120, 150, and 180 °C for PR-VA) on
BiI<sub>3</sub> film morphology have been investigated. As found in
the study, grain size increased and film uniformity improved as temperature
was raised from 90 to 150 °C. The photovoltaic devices based
on BiI<sub>3</sub> films processed at 150 °C with PR-VA treatment
showed power conversion efficiency (PCE) of 0.5% with high reproducibility,
which is, so far, the best PCE reported for BiI<sub>3</sub> photovoltaic
device employing organic hole-transporting material (HTM), owing to
the increase in grain size and uniform morphology of BiI<sub>3</sub> film. These devices showed stable performance even after 30 days
of exposure to 50% relative humidity, and after 100 °C heat stress
and 20 min light soaking test. More importantly, the study reveals
many challenges and room (discussed in the details) for further development
of the BiI<sub>3</sub> photovoltaic devices
Carbohydrate-Based Label-Free Detection of <i>Escherichia coli</i> ORN 178 Using Electrochemical Impedance Spectroscopy
A label-free biosensor for <i>Escherichia coli</i> (<i>E. coli</i>) ORN 178 based on faradaic electrochemical impedance spectroscopy (EIS) was developed. α-Mannoside or β-galactoside was immobilized on a gold disk electrode using a self-assembled monolayer (SAM) via a spacer terminated in a thiol functionality. Impedance measurements (Nyquist plot) showed shifts due to the binding of <i>E. coli</i> ORN 178, which is specific for α-mannoside. No significant change in impedance was observed for <i>E. coli</i> ORN 208, which does not bind to α-mannoside. With increasing concentrations of <i>E. coli</i> ORN 178, electron-transfer resistance (<i>R</i><sub>et</sub>) increases before the sensor is saturated. After the Nyquist plot of <i>E. coli</i>/mixed SAM/gold electrode was modeled, a linear relationship between normalized <i>R</i><sub>et</sub> and the logarithmic value of <i>E. coli</i> concentrations was found in a range of bacterial concentration from 10<sup>2</sup> to 10<sup>3</sup> CFU/mL. The combination of robust carbohydrate ligands with EIS provides a label-free, sensitive, specific, user-friendly, robust, and portable biosensing system that could potentially be used in a point-of-care or continuous environmental monitoring setting
Rationally Designed 2‑in‑1 Nanoparticles Can Overcome Adaptive Resistance in Cancer
The
development of resistance is the major cause of mortality in
cancer. Combination chemotherapy is used clinically to reduce the
probability of evolution of resistance. A similar trend toward the
use of combinations of drugs is also emerging in the application of
cancer nanomedicine. However, should a combination of two drugs be
delivered from a single nanoparticle or should they be delivered in
two different nanoparticles for maximal efficacy? We explored these
questions in the context of adaptive resistance, which emerges as
a phenotypic response of cancer cells to chemotherapy. We studied
the phenotypic dynamics of breast cancer cells under cytotoxic chemotherapeutic
stress and analyzed the data using a phenomenological mathematical
model. We demonstrate that cancer cells can develop adaptive resistance
by entering into a predetermined transitional trajectory that leads
to phenocopies of inherently chemoresistant cancer cells. Disrupting
this deterministic program requires a unique combination of inhibitors
and cytotoxic agents. Using two such combinations, we demonstrate
that a 2-in-1 nanomedicine can induce greater antitumor efficacy by
ensuring that the origins of adaptive resistance are terminated by
deterministic spatially constrained delivery of both drugs to the
target cells. In contrast, a combination of free-form drugs or two
nanoparticles, each carrying a single payload, is less effective,
arising from a stochastic distribution to cells. These findings suggest
that 2-in-1 nanomedicines could emerge as an important strategy for
targeting adaptive resistance, resulting in increased antitumor efficacy
Algorithm for Designing Nanoscale Supramolecular Therapeutics with Increased Anticancer Efficacy
In
the chemical world, evolution is mirrored in the origin of nanoscale
supramolecular structures from molecular subunits. The complexity
of function acquired in a supramolecular system over a molecular subunit
can be harnessed in the treatment of cancer. However, the design of
supramolecular nanostructures is hindered by a limited atomistic level
understanding of interactions between building blocks. Here, we report
the development of a computational algorithm, which we term Volvox
after the first multicellular organism, that sequentially integrates
quantum mechanical energy-state- and force-field-based models with
large-scale all-atomistic explicit water molecular dynamics simulations
to design stable nanoscale lipidic supramolecular structures. In one
example, we demonstrate that Volvox enables the design of a nanoscale
taxane supramolecular therapeutic. In another example, we demonstrate
that Volvox can be extended to optimizing the ratio of excipients
to form a stable nanoscale supramolecular therapeutic. The nanoscale
taxane supramolecular therapeutic exerts greater antitumor efficacy
than a clinically used taxane <i>in vivo</i>. Volvox can
emerge as a powerful tool in the design of nanoscale supramolecular
therapeutics for effective treatment of cancer
Algorithm for Designing Nanoscale Supramolecular Therapeutics with Increased Anticancer Efficacy
In
the chemical world, evolution is mirrored in the origin of nanoscale
supramolecular structures from molecular subunits. The complexity
of function acquired in a supramolecular system over a molecular subunit
can be harnessed in the treatment of cancer. However, the design of
supramolecular nanostructures is hindered by a limited atomistic level
understanding of interactions between building blocks. Here, we report
the development of a computational algorithm, which we term Volvox
after the first multicellular organism, that sequentially integrates
quantum mechanical energy-state- and force-field-based models with
large-scale all-atomistic explicit water molecular dynamics simulations
to design stable nanoscale lipidic supramolecular structures. In one
example, we demonstrate that Volvox enables the design of a nanoscale
taxane supramolecular therapeutic. In another example, we demonstrate
that Volvox can be extended to optimizing the ratio of excipients
to form a stable nanoscale supramolecular therapeutic. The nanoscale
taxane supramolecular therapeutic exerts greater antitumor efficacy
than a clinically used taxane <i>in vivo</i>. Volvox can
emerge as a powerful tool in the design of nanoscale supramolecular
therapeutics for effective treatment of cancer