Environmental reservoirs of antibiotic resistance (AR) are a growing concern that are gathering more attention as potential sources for human infection. Carbapenem-resistant Enterobacteriaceae (CRE) ...are extremely dangerous, as carbapenems are often drugs of last resort that are used to treat multi-drug resistant infections. Among the genes capable of conferring carbapenem resistance to bacteria, the most transferrable are those that produce carbapenemase, an enzyme that hydrolyzes carbapenems and other β-lactam antibiotics. The goal of this review was to comprehensively identify global environmental reservoirs of carbapenemase-producing genes, as well as identify potential routes of transmission to humans. The genes of interest were Klebsiella pneumoniae carbapenemase (KPC), New Delhi Metallo-β-lactamase (NDM), Oxacillinase-48-type carbapenemases (OXA-48), and Verona Integron-Mediated Metallo-β-lactamase (VIM). Carbapenemase genes have been reported in the environment on almost every continent. Hospital and municipal wastewater, drinking water, natural waterways, sediments, recreational waters, companion animals, wildlife, agricultural environments, food animals, and retail food products were identified as current reservoirs of carbapenemase-producing bacteria and genes. Humans have been recorded as carrying CRE, without recent admittance to a hospital or long-term care facility in France, Egypt, and China. CRE infections from the environment have been reported in patients in Montpellier, France and Cairo, Egypt. This review demonstrates the need for 1) comprehensive monitoring of AR not only in waterways, but also other types of environmental matrices, such as aerosol, dusts, periphyton, and surfaces in indoor environments; and 2) action to reduce the prevalence and mitigate the effects of these potentially deadly resistance genes. In order to develop an accurate quantitative model for environmental dimensions of AR, longitudinal sampling and quantification of AR genes and bacteria are needed, using a One Health approach.
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•This paper identifies different global environmental reservoirs carrying CRE.•First study focusing on carbapenem-resistant genes in all environmental reservoirs.•Carbapenemase-producing genes were identified in water, animals, food, and soil.•There have been two reported human infections from environmentally sourced CRE.•Quantitative dynamics of CRE transmission and exposure is needed for management.
Concentration quenching of thermally activated delayed fluorescence is found to be dominated by electron‐exchange interactions, as described by the Dexter energy‐transfer model. Owing to the ...short‐range nature of the electron‐exchange interactions, even a small modulation in the molecular geometric structure drastically affects the concentration‐quenching, leading to enhanced solid‐state photoluminescence and electroluminescence quantum efficiencies.
Luminescent materials consisting of boron clusters, such as carboranes, have attracted immense interest in recent years. In this study, luminescent organic–inorganic conjugated systems based on ...o‐carboranes directly bonded to electron‐donating and electron‐accepting π‐conjugated units were elaborated as novel optoelectronic materials. These o‐carborane derivatives simultaneously possessed aggregation‐induced emission (AIE) and thermally activated delayed fluorescence (TADF) capabilities, and showed strong yellow‐to‐red emissions with high photoluminescence quantum efficiencies of up to 97 % in their aggregated states or in solid neat films. Organic light‐emitting diodes utilizing these o‐carborane derivatives as a nondoped emission layer exhibited maximum external electroluminescence quantum efficiencies as high as 11 %, originating from TADF.
Two sides of the same coin: Organic–inorganic hybrid molecules consisting of an o‐carborane tethered with electron donor and acceptor π‐conjugated units exhibit efficient photoluminescence and electroluminescence based on aggregation‐induced delayed fluorescence (AIDF).
Thermally activated delayed fluorescence (TADF) π‐conjugated polymers are developed for solution‐processed TADF–OLEDs. Benzophenone‐based alternating donor–acceptor structures contribute to the small ...∆EST, enabling efficient exciton‐harvesting through TADF. Solution‐processed OLEDs using the TADF polymers as emitters can achieve high maximum external electroluminescence efficiencies of up to 9.3%.
Self-assembly has proven to be a widely successful synthetic strategy for functional materials, especially for metal-organic materials (MOMs), an emerging class of porous materials consisting of ...metal-organic frameworks (MOFs) and metal-organic polyhedra (MOPs). However, there are areas in MOM synthesis in which such self-assembly has not been fully utilized, such as controlling the interior of MOM crystals. Here we demonstrate sequential self-assembly strategy for synthesizing various forms of MOM crystals, including double-shell hollow MOMs, based on single-crystal to single-crystal transformation from MOP to MOF. Moreover, this synthetic strategy also yields other forms, such as solid, core-shell, double and triple matryoshka, and single-shell hollow MOMs, thereby exhibiting form evolution in MOMs. We anticipate that this synthetic approach might open up a new direction for the development of diverse forms in MOMs, with highly advanced areas such as sequential drug delivery/release and heterogeneous cascade catalysis targeted in the foreseeable future.
Calcium ions are ubiquitous signalling molecules in all multicellular organisms, where they mediate diverse aspects of intracellular and extracellular communication over widely varying temporal and ...spatial scales
. Though techniques to map calcium-related activity at a high resolution by optical means are well established, there is currently no reliable method to measure calcium dynamics over large volumes in intact tissue
. Here, we address this need by introducing a family of magnetic calcium-responsive nanoparticles (MaCaReNas) that can be detected by magnetic resonance imaging (MRI). MaCaReNas respond within seconds to Ca
changes in the 0.1-1.0 mM range, suitable for monitoring extracellular calcium signalling processes in the brain. We show that the probes permit the repeated detection of brain activation in response to diverse stimuli in vivo. MaCaReNas thus provide a tool for calcium-activity mapping in deep tissue and offer a precedent for the development of further nanoparticle-based sensors for dynamic molecular imaging with MRI.
Even though VR(Virtual Reality) shopping provides new opportunities for today’s marketers, it is not readily embraced by consumers. In this research, we aim to understand the underlying factors that ...facilitate the adoption of VR technology, by incorporating the consumer flow theory and the Technology Acceptance Model (TAM). Specifically, we find that factors that enhance consumer flow (i.e., telepresence, challenge, body ownership, and control) are positively associated with antecedent factors of technology acceptance (i.e. playfulness and usefulness), which are, in turn, associated with greater intentions to adopt and utilize VR technology in a consumer setting. We also investigate the moderating role of technology readiness and time distortion on the relationship between telepresence and playfulness. Data was collected by having participants use VR glasses in an actual VR supermarket that was created for this study. By elucidating factors that help consumer adoption of VR technology and emphasizing unique factors inherent to VR (i.e. telepresence and time distortion), this paper provides important contributions to the literature and implications for marketing managers.
BTB domain and CNC homology 1 (BACH1) is a transcription factor that is highly expressed in tumors including breast and lung, relative to their non-tumor tissues. BACH1 is known to regulate multiple ...physiological processes including heme homeostasis, oxidative stress response, senescence, cell cycle, and mitosis. In a tumor, BACH1 promotes invasion and metastasis of cancer cells, and the expression of BACH1 presents a poor outcome for cancer patients including breast and lung cancer patients. Recent studies identified novel functional roles of BACH1 in the regulation of metabolic pathways in cancer cells. BACH1 inhibits mitochondrial metabolism through transcriptional suppression of mitochondrial membrane genes. In addition, BACH1 suppresses activity of pyruvate dehydrogenase (PDH), a key enzyme that converts pyruvate to acetyl-CoA for the citric acid (TCA) cycle through transcriptional activation of pyruvate dehydrogenase kinase (PDK). Moreover, BACH1 increases glucose uptake and lactate secretion through the expression of metabolic enzymes involved such as hexokinase 2 (HK2) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) for aerobic glycolysis. Pharmacological or genetic inhibition of BACH1 could reprogram by increasing mitochondrial metabolism, subsequently rendering metabolic vulnerability of cancer cells against mitochondrial respiratory inhibition. Furthermore, inhibition of BACH1 decreased antioxidant-induced glycolysis rates as well as reduced migration and invasion of cancer cells, suggesting BACH1 as a potentially useful cancer therapeutic target.
Acute kidney injury (AKI) is a prevalent and lethal adverse event that severely affects cancer patients receiving chemotherapy. It is correlated with the collateral damage to renal cells caused by ...reactive oxygen species (ROS). Currently, ROS management is a practical strategy that can reduce the risk of chemotherapy-related AKI, but at the cost of chemotherapeutic efficacy. Herein, we report catalytic activity tunable ceria nanoparticles (CNPs) that can prevent chemotherapy-induced AKI without interference with chemotherapeutic agents. Specifically, in the renal cortex, CNPs exhibit catalytic activity that decomposes hydrogen peroxide, and subsequently regulate the ROS-involved genes by activating the Nrf2/Keap1 signaling pathway. These restore the redox homeostasis for the protection of kidney tubules. Under an acidic tumor microenvironment, CNPs become inert due to the excessive H
that disrupts the re-exposure of active catalytic sites, allowing a buildup of chemotherapy-mediated ROS generation to kill cancer cells. As ROS-modulating agents, CNPs incorporated with context-dependent catalytic activity, hold a great potential for clinical prevention and treatment of AKI in cancer patients.
•We report a novel SERS-based lateral flow (LF) assay for the sensitive detection of bacterial pathogens.•Quantitative analysis of low-abundance target bacteria is possible using this SERS assay ...platform.•This approach provides new insights into early detection of specific bacterial pathogens in the field.
Bacterial pathogens such as Yersinia pestis, Francisella tularensis, and Bacillus anthracis are classified into the highest rank of potential bioterrorism agents. Colorimetric lateral flow assay (LFA) strips are commercially available but these conventional strips have drawbacks in terms of low sensitivity and limit of quantitative analysis. Therefore, there is an urgent need for a new sensing platform to detect these pathogens in the early contamination stage. In this study, a novel surface-enhanced Raman scattering (SERS)-based LFA strip was developed for sensitive detection of bacterial pathogens. Target-specific SERS nanotags (Raman reporter-labeled gold nanoparticles) were used as an alternative to the gold nanoparticles in conventional LFA strips. Using these SERS nanotags the presence of bacteria could be identified through a simple color change in the test line. Additionally, highly sensitive and accurate quantitative analysis could be performed by monitoring the characteristic Raman peak intensity of SERS nanotags that were captured in the test line. This highly sensitive method required a short assay time (15 min) and a tiny volume of pathogen sample (40 μL). We believe that the proposed SERS-based LFA technique has great potential as a valuable tool in the early detection of specific bacterial pathogens in the field due to its excellent analytical sensitivity.
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