Advanced organic bioelectronics enable smooth fusion between modern electronics and biological systems for better physiological monitoring and pathological examinations. Photon‐regulated ...bioelectronics are especially desirable due to the non‐contact impact, remote‐control, and even self‐powered operation. However, few studies have addressed the advanced photon‐enabled organic photoelectrochemical transistor (OPECT) biosensors capable of operation at zero gate bias. Here, on the basis of a hydrogel/graphene oxide hybrid (denoted as HGH), a multifunctional HGH‐gated OPECT biosensor is presented, which is exemplified by Ca2+‐triggered gelation on the CdS quantum dot (QD) photoelectrode linking with a sandwich immunoassay toward human IgG as the model target. Gelation of HGH on the CdS QD gate electrode can not only inhibit the interfacial mass transfer on the gate/electrolyte interface, but also significantly block the light absorption of CdS QDs, leading to the corresponding change of the channel currents of OPECT device. At zero gate bias, this OPECT biosensor exhibits high gain in response to light and good analytical performance for human IgG with a detection limit of 50 fg mL–1. Given the numerous intelligent hydrogel materials and their potential interactions with light, this work unveils a general platform for developing a new class of hydrogel‐gated OPECT bioelectronics and beyond.
A multifunctional hydrogel‐gated organic photoelectrochemical transistor biosensor is constructed using a Ca2+‐triggered hydrogel/graphene oxide hybrid on the CdS quantum dot photosensitive gate electrode linking with a sandwich immunoassay toward human IgG as the model target. The proposed biosensor exhibits high gain in response to light and good analytical performance at zero gate bias.
Noble metal nanoparticles are promising catalysts in electrochemical reactions, while understanding the relationship between the structure and reactivity of the particles is important to achieve ...higher efficiency of electrocatalysis, and promote the development of single‐molecule electrochemistry. Electrogenerated chemiluminescence (ECL) was employed to image the catalytic oxidation of luminophore at single Au, Pt, and Au‐Pt Janus nanoparticles. Compared to the monometal nanoparticles, the Janus particle structure exhibited enhanced ECL intensity and stability, indicating better catalytic efficiency. On the basis of the experimental results and digital simulation, it was concluded that a concentration difference arose at the asymmetric bimetallic interface according to different heterogeneous electron‐transfer rate constants at Au and Pt. The fluid slip around the Janus particle enhanced local redox reactions and protected the particle surface from passivation.
Electrocatalytic oxidation of a luminophore at single Au, Pt, and Au‐Pt Janus nanoparticles was studied using electrogenerated chemiluminescence (ECL) microscopy. Compared to the monometal nanoparticles, the Janus particle structure exhibited enhanced ECL intensity and stability, indicating better catalytic efficiency.
Uncovering the relationship between the structure, surface properties and electrochemical activity of nanoparticles is of great importance for constructing novel nanocatalysts and highly efficient ...electrocatalytic devices. Here we report a study of the heterogeneously distributed electrocatalytic activity on individual 2D gold nanoplates. On the basis of electrogenerated chemiluminescence (ECL) microscopy, the size, shape, and site-specific catalytic activity of 2D nanocrystals could be directly imaged at the single particle level with submicron resolution. Since the microelectrode effect with higher fluxes at the perimeter was offset by diffusion of excited species of Ru(bpy)
, calculated by finite element simulation, the ECL distribution was supposed to be uniform on the micro-sized plates. Therefore, it is highly possible that the observed nonuniform ECL distribution at single nanoplates reflected distinct surface electrocatalytic activities at different sites. Furthermore, ECL microscopy allows continuous
imaging, which elucidates the time-varying changes in the spatial distribution of electrocatalytic activity on individual nanoplates, indicating that the corners and edges with more defect sites exhibit higher reactivity, but lower stability than the flat facet. We believe that real-time and high-throughput ECL microscopy may lead to more comprehensive understanding of reactivity patterns of single nanocatalysts.
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•Ecological security pattern of Pearl River Delta urban agglomeration was evaluated.•Various evaluation methods and index system were analyzed by Robustness analysis.•BP-DEMATEL model ...was applied to examine the relationship among the indicators.•A creative method was developed to evaluate regional ecological security pattern.
Over the past four decades, many Chinese cities have faced serious ecological security pressures with rapid urbanization, especially, in the economically developed areas such as the Pearl River Delta urban agglomeration (PRD). The question of how to accurately evaluate the ecological security status and determine the influencing factors has become a realistic problem for the sustainable development of these cities. However, this analysis is hard to do because of the variable results derived from different evaluation methods and index systems. Robustness analysis is a broad method that is used for stable screening of different results. In this study, robustness analysis was conducted for 20 evaluation methods and 20 index systems. The most stable method was screened, which was the complex correlation coefficient method for indicator weight calculation, associated with the grey clustering method for ecological security evaluation. Moreover, the robustness analysis suggested that the stability of various index systems was better than that of various evaluation methods. According to the final urban ecological security pattern, the BP-DEMATEL model analyzed the influencing factors. The effect and intensity of each indicator were analyzed, which suggested that the total value of ecosystem service was the fundamental influencing indicator on the urban ecological security of the PRD. Six other driving influencing indicators including GDP per capita, normalize difference vegetation index, gross product of primary industry per unit area and anthropogenic disturbance index, as well as five characteristic influencing indicators were determined. Therefore, ecological elements were the most important guarantee of urban security in the PRD urban agglomeration. However, socio-economic elements played a key role in promoting urban ecological recovery. A creative approach was developed in this study to evaluate the ecological security of a region by integrating numerous methods and index systems. The comprehensive results provide constructive suggestions for the sustainable development of cities in the PRD urban agglomeration.
Long non-coding RNAs (lncRNAs) are important regulators of diverse biological processes. Here we report on functional identification and characterization of a novel long intergenic non-coding RNA ...with MyoD-regulated and skeletal muscle-restricted expression that promotes the activation of the myogenic program, and is therefore termed Linc-RAM (Linc-RNA Activator of Myogenesis). Linc-RAM is transcribed from an intergenic region of myogenic cells and its expression is upregulated during myogenesis. Notably, in vivo functional studies show that Linc-RAM knockout mice display impaired muscle regeneration due to the differentiation defect of satellite cells. Mechanistically, Linc-RAM regulates expression of myogenic genes by directly binding MyoD, which in turn promotes the assembly of the MyoD-Baf60c-Brg1 complex on the regulatory elements of target genes. Collectively, our findings reveal the functional role and molecular mechanism of a lineage-specific Linc-RAM as a regulatory lncRNA required for tissues-specific chromatin remodelling and gene expression.
Ganoderma lucidum is a mushroom with traditional medicinal properties that has been widely used in China and other countries in Eastern Asia. Ganoderic acids (GA) produced by G. lucidum exhibit ...important pharmacological activities. Previous studies have demonstrated that methyl jasmonate (MeJA) is a potent inducer of GA biosynthesis and the expression of genes involved in the GA biosynthesis pathway in G. lucidum. To further explore the mechanism of GA biosynthesis, cDNA-Amplified Fragment Length Polymorphism (cDNA-AFLP) was used to identify genes that are differentially expressed in response to MeJA. Using 64 primer combinations, over 3910 transcriptionally derived fragments (TDFs) were obtained. Reliable sequence data were obtained for 390 of 458 selected TDFs. Ninety of these TDFs were annotated with known functions through BLASTX searching the GenBank database, and 12 annotated TDFs were assigned into secondary metabolic pathways by searching the KEGGPATHWAY database. Twenty-five TDFs were selected for qRT-PCR analysis to confirm the expression patterns observed with cDNA-AFLP. The qRT-PCR results were consistent with the altered patterns of gene expression revealed by the cDNA-AFLP technique. Additionally, the transcript levels of 10 genes were measured at the mycelium, primordia, and fruiting body developmental stages of G. lucidum. The greatest expression levels were reached during primordia for all of the genes except cytochrome b2 reached its highest expression level in the mycelium stage. This study not only identifies new candidate genes involved in the regulation of GA biosynthesis but also provides further insight into MeJA-induced gene expression and secondary metabolic response in G. lucidum.
3′,5′-Cyclic adenosine monophosphate (cAMP) is an important metabolite that is specifically enriched in jujube. However, the effect of cAMP on jujube cellular responses has not been comprehensively ...studied. Here, we established jujube cell suspension cultures and investigated the calcium influx in response to cAMP treatment through protoplast isolation and fluorescence intensity. Firstly, cAMP treatment could promote jujube growth and increase the content of endogenous cAMP. Using transcriptome analysis with transgenic Arabidopsis plants overexpressing adenylate cyclase (ZjAC) as a positive control, we identified 60 calcium-related differential expressed genes (DEGs) that contributed to the calcium signaling and inter- or intra-cellular responses. Pharmacological treatments such as cAMP and the calcium ionophore A23187 could induce ZjAC expression, the accumulation of cAMP and calcium influx in jujube cells, while ethylene glycol tetraacetic acid (EGTA) or bithionol treatment inhibited these changes. Moreover, the calcium channels and transporters in calcium influx, such as the ZjCNGC2 channel and the mitogen activated protein (MAP) kinase pathway, could be activated by cAMP treatment. In summary, our findings demonstrated that cAMP biosynthesis is dependent on calcium influx and the amplifying effect between calcium and cAMP may be involved in intracellular signal induction, which might contribute to the growth and development of jujube.
Rapid and personalized single-cell drug screening testing plays an essential role in acute myeloid leukemia drug combination chemotherapy. Conventional chemotherapeutic drug screening is a ...time-consuming process because of the natural resistance of cell membranes to drugs, and there are still great challenges related to using technologies that change membrane permeability such as sonoporation in high-throughput and precise single-cell drug screening with minimal damage. In this study, we proposed an acoustic streaming-based non-invasive single-cell drug screening acceleration method, using high-frequency acoustic waves (>10 MHz) in a concentration gradient microfluidic device. High-frequency acoustics leads to increased difficulties in inducing cavitation and generates acoustic streaming around each single cell. Therefore, single-cell membrane permeability is non-invasively increased by the acoustic pressure and acoustic streaming-induced shear force, which significantly improves the drug uptake process. In the experiment, single human myeloid leukemia mononuclear (THP-1) cells were trapped by triangle cell traps in concentration gradient chips with different cytarabine (Ara-C) drug concentrations. Due to this dual acoustic effect, the drugs affect cell viability in less than 30 min, which is faster than traditional methods (usually more than 24 h). This dual acoustic effect-based drug delivery strategy has the potential to save time and reduce the cost of drug screening, when combined with microfluidic technology for multi-concentration drug screening. This strategy offers enormous potential for use in multiple drug screening or efficient drug combination screening in individualized/personalized treatments, which can greatly improve efficiency and reduce costs.
An acoustic streaming based rapid single-cell drug screening microfluidic device is developed. It is achieved by acoustic streaming non-invasively changing cell membrane permeability to accelerate drug absorption in drug concentration gradient field.
Background and aims:
The application of prone positioning with acute hypoxemic respiratory failure (AHRF) or acute respiratory distress syndrome (ARDS) in non-intubation patients is increasing ...gradually, applying prone positioning for more high-flow nasal oxygen therapy (HFNC) and non-invasive ventilation (NIV) patients. This meta-analysis evaluates the efficacy and tolerance of prone positioning combined with non-invasive respiratory support in patients with AHRF or ARDS.
Methods:
We searched randomized controlled trials (RCTs) (prospective or retrospective cohort studies, RCTs and case series) published in PubMed, EMBASE and the Cochrane Central Register of Controlled Trials from 1 January 2000 to 1 July 2020. We included studies that compared prone and supine positioning with non-invasive respiratory support in awake patients with AHRF or ARDS. The meta-analyses used random effects models. The methodological quality of the RCTs was evaluated using the Newcastle–Ottawa quality assessment scale.
Results:
A total of 16 studies fulfilled selection criteria and included 243 patients. The aggregated intubation rate and mortality rate were 33% 95% confidence interval (CI): 0.26–0.42, I2 = 25%, 4% (95% CI: 0.01–0.07, I2 = 0%), respectively, and the intolerance rate was 7% (95% CI: 0.01–0.12, I2 = 5%). Prone positioning increased PaO2/FiO2 mean difference (MD) = 47.89, 95% CI: 28.12–67.66; p < 0.00001, I2 = 67% and SpO2 (MD = 4.58, 95% CI: 1.35–7.80, p = 0.005, I2 = 97%), whereas it reduced respiratory rate (MD = −5.01, 95% CI: −8.49 to −1.52, p = 0.005, I2 = 85%). Subgroup analyses demonstrated that the intubation rate of shorter duration prone (⩽5 h/day) and longer duration prone (>5 h/day) were 34% and 21%, respectively; and the mortality rate of shorter duration prone (⩽5 h/day) and longer duration prone (>5 h/day) were 6% and 0%, respectively. PaO2/FiO2 and SpO2 were significantly improved in COVID-19 patients and non-COVID-19 patients.
Conclusion:
Prone positioning could improve the oxygenation and reduce respiratory rate in both COVID-19 patients and non-COVID-19 patients with non-intubated AHRF or ARDS.
The reviews of this paper are available via the supplemental material section.
In a search for novel nonsugar α-glucosidase inhibitors for diabetes treatment, a series of N-(phenylsulfonyl)thiazole-2-carboxamide derivatives were designed and synthesized, the α-glucosidase ...inhibitory activities were then evaluated. Several compounds with promising α-glucosidase inhibitory effects were identified. Among these, compound W24 which shows low cytotoxicity and good α-glucosidase inhibitory activity with an IC
value of 53.0 ± 7.7 μM, is more competitive compared with the commercially available drug acarbose (IC
= 228.3 ± 9.2 μM). W24 was identified as a promising candidate in the development of α-glucosidase inhibitors. Molecular docking studies and molecular dynamics simulation were also performed to reveal the binding pattern of the active compound to α-glucosidase, and the binding free energy of the best compound W24 was 36.3403 ± 3.91 kcal/mol.
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