74 research outputs found
Recommended from our members
Surface Immobilization of Redox-Labile Fluorescent Probes: Enabling Single-Cell Co-Profiling of Aerobic Glycolysis and Oncogenic Protein Signaling Activities.
An analytical method is described for profiling lactate production in single cells via the use of coupled enzyme reactions on surface-grafted resazurin molecules. The immobilization of the redox-labile probes was achieved through chemical modifications on resazurin, followed by bio-orthogonal click reactions. The lactate detection was demonstrated to be sensitive and specific. The method was incorporated into a single-cell barcode chip for simultaneous quantification of aerobic glycolysis activities and oncogenic signaling phosphoproteins in cancer. The interplay between glycolysis and oncogenic signaling activities was interrogated on a glioblastoma cell line. Results revealed a drug-induced oncogenic signaling reliance accompanying shifted metabolic paradigms. A drug combination that exploits this induced reliance exhibited synergistic effects in growth inhibition
Recommended from our members
Multi-omic single-cell snapshots reveal multiple independent trajectories to drug tolerance in a melanoma cell line
The determination of individual cell trajectories through a high-dimensional cell-state space is an outstanding challenge for understanding biological changes ranging from cellular differentiation to epigenetic responses of diseased cells upon drugging. We integrate experiments and theory to determine the trajectories that single BRAF^(V600E) mutant melanoma cancer cells take between drug-naive and drug-tolerant states. Although single-cell omics tools can yield snapshots of the cell-state landscape, the determination of individual cell trajectories through that space can be confounded by stochastic cell-state switching. We assayed for a panel of signaling, phenotypic, and metabolic regulators at points across 5 days of drug treatment to uncover a cell-state landscape with two paths connecting drug-naive and drug-tolerant states. The trajectory a given cell takes depends upon the drug-naive level of a lineage-restricted transcription factor. Each trajectory exhibits unique druggable susceptibilities, thus updating the paradigm of adaptive resistance development in an isogenic cell population
A promising Na3V2(PO4)(3) cathode for use in the construction of high energy batteries
High-energy batteries need significant cathodes which can simultaneously provide large specific
capacities and high discharge plateaus. NASICON-structured Na3V2(PO4)3 (NVP) has been utilised as a
promising cathode to meet this requirement and be used in the construction of high energy batteries. For
a hybrid-ion battery by employing metallic lithium as an anode, NVP exhibits an initial specific capacity of
170 mA h g 1 in the voltage range of 1.6–4.8 V with a long discharge plateau around 3.7 V. Three Na(2)
sites for NVP are found capable to be utilised through the application of a wide voltage window but only
two of them are able to undergo ions exchange to produce a NaLi2V2(PO4)3 phase. However, a hybrid-ion
migration mechanism is suggested to exist to describe the whole ion transport in which the effects of a
Na-ion ‘‘barrier’’ results in a lowered ion diffusion rate and observed specific capacity.
1. Introduction
Lithium-ion battery (LIB) technology is critically needed for many
applications in a plethora of industries and is an important energystorage
solution which can be potentially applied, for instance
into electric vehicles (EVs).1,2 However, LIB has continued to be
primarily relegated by the electronics market mainly due to its
cost and material issues3 and the lack of high-performance
cathode materials have become a technological bottleneck for
the commercial development of advanced LIB.4 Particularly for
the entrance of LIB into high energy fields, such as EVs and
renewable energy storage in smart grids, the demand for highcapacity
and voltage cathodes is starting to become a key focus
of research.
In the search for new positive-electrode materials for LIB,
recent research has focused upon nano-structured lithium
transitional-metal phosphates that exhibit desirable properties
such as high energy storage capacities combined with electrochemical
stability.5,6 Olivine LiFePO4,7 as one member of this
class, has risen to prominence so far due to other characteristics
involving low cost, low environmental impact and safety,
which ar
Trajectories from Snapshots: Integrated proteomic and metabolic single-cell assays reveal multiple independent adaptive responses to drug tolerance in a BRAF-mutant melanoma cell line
The determination of individual cell trajectories through a high-dimensional cell-state space is an outstanding challenge, with relevance towards understanding biological changes ranging from cellular differentiation to epigenetic (adaptive) responses of diseased cells to drugging. We report on a combined experimental and theoretic method for determining the trajectories that specific highly plastic BRAFV600E mutant patient-derived melanoma cancer cells take between drug-naive and drug-tolerant states. Recent studies have implicated non-genetic, fast-acting resistance mechanisms are activated in these cells following BRAF inhibition. While single-cell highly multiplex omics tools can yield snapshots of the cell state space landscape sampled at any given time point, individual cell trajectories must be inferred from a kinetic series of snapshots, and that inference can be confounded by stochastic cell state switching. Using a microfludic-based single-cell integrated proteomic and metabolic assay, we assayed for a panel of signaling, phenotypic, and metabolic regulators at four time points during the first five days of drug treatment. Dimensional reduction of the resultant data set, coupled with information theoretic analysis, uncovered a complex cell state landscape and identified two distinct paths connecting drug-naive and drug-tolerant states. Cells are shown to exclusively traverse one of the two pathways depending on the level of the lineage restricted transcription factor MITF in the drug-naive cells. The two trajectories are associated with distinct signaling and metabolic susceptibilities, and are independently druggable. Our results update the paradigm of adaptive resistance development in an isogenic cell population and offer insight into the design of more effective combination therapies
Single-cell profiling of D-2-hydroxyglutarate using surface-immobilized resazurin analogs.
Ratiometric Electrochemical Sensor for Effective and Reliable Detection of Ascorbic Acid in Living Brains
The <i>in vivo</i> detection of ascorbic acid (AA), one
of the physiologically important cerebral neurochemicals, is critical
to probe and understand brain functions. Electrochemical sensors are
convenient for AA detection. However, conventional electrochemical
sensors usually suffer from several challenges, such as sluggish electron
transfer kinetics for AA oxidation and poor reproducibility. To address
these challenges, here we report ratiometric electrochemical sensors
for effective and reliable detection of AA in living brains. The sensors
were constructed by immobilizing preassembled thionine/Ketjen black
(KB) nanocomposites onto glassy carbon (GC) electrodes or carbon fiber
microelectrodes (CFMEs). The KB in the rationally functionalized nanocomposites
efficiently facilitated AA oxidation at a relatively negative potential
(∼−0.14 V) without particular physical or chemical pretreatment,
forming the basis of selective measurement of AA. With a well-defined
and reversible pair of redox wave at −0.22 V, the assembled
thionine acted as an internal reference to substantially alleviate
the lab-to-lab, person-to-person, and electrode-to-electrode variations.
The <i>in vitro</i> experiments demonstrated that the sensors
exhibited extremely high reproducibility and stability toward selective
measurement of AA. More, with operational simplicity and robustness
in analytical performance, the designed sensors were successfully
applied to <i>in vivo</i> effectively, selectively, and
reliably monitor the dynamic change of cerebral AA associated with
pathological processes (i.e., salicylate-induced tinnitus as the model)
in living rats’ brains. This study not only offers a new strategy
for construction of ratiometric electrochemical sensors but also opens
a new way for selective and reliable detection of neurochemicals for
probing brain functions
- …