Impact of Surface Chemistry on Emulsion-Electrode Interactions and Electron-Transfer Kinetics in the Single-Entity Electrochemistry.

Single-entity electrochemistry (SEE) provides powerful means to track a single particle, single cell, and even single molecule from the nano to microscale. The electrode serves as not only the detector of collision but also the surface supplier in SEE, and the fundamental understanding of the electrode surface chemistry on the dynamic particle-electrode interactions and electrochemical responses of a single particle still remains unexplored, particularly for soft particles. Herein, dynamic interactions of microemulsions and the interaction-controlled electron-transfer (ET) kinetics are studied employing SEE and fluorescence spectroscopy. The o/w-type nitrobenzene emulsions were prepared with the surfactant-type room temperature ionic liquids (RTILs). Biased the electrode potential for the reduction of 7,7,8,8-tetracyanoquinodimethane within emulsions, it is surprising to see the distinct collision current signals on the carbon fiber ultramicroelectrode (C UME) and Au ultramicroelectrode (Au UME) in the late stage of chronoamperometric measurements. Theoretical understanding was made to determine the ET kinetics behind the disparate current signals. It is believed that the electrode surface chemistry, i.e., the surface energy, has a great influence on the dynamic emulsion-electrode interactions and ET kinetics. On the hydrophilic surface of Au UME, emulsions tend to decompose/detach from the electrode surface immediately after colliding. In contrast, on the lipophilic surface of C UME with lower surface energy, a layer of oil phase accumulated by the coalescence of emulsions and the migration of the precedent colliding emulsions, which would serve as a barrier to block ET via tunneling as manifested by the gradual slowdown of ET rate and the reduced collision frequency in the late stage of measurement. The impacts of the emulsion size and amphiphilicity of RTILs on the C UME-emulsion interactions and ET kinetics were also investigated.

Recent progress in promoting the bioavailability of polyphenols in plant-based foods.

Polyphenols are important constituents of plant-based foods, exhibiting a range of beneficial effects. However, many phenolic compounds have low bioavailability because of their low water solubility, chemical instability, food matrix effects, and interactions with other nutrients. This article reviews various methods of improving the bioavailability of polyphenols in plant-based foods, including fermentation, natural deep eutectic solvents, encapsulation technologies, co-crystallization and amorphous solid dispersion systems, and exosome complexes. Several innovative technologies have recently been deployed to improve the bioavailability of phenolic compounds. These technologies may be utilized to increase the healthiness of plant-based foods. Further research is required to better understand the mechanisms of action of these novel approaches and their potential to be used in food production.

Neutrophil membrane-coated nanoparticles exhibit increased antimicrobial activities in an anti-microbial resistant K. pneumonia infection model.

OBJECTIVE: To investigate the efficacy and safety of neutrophil membrane-coated nanoparticles mediated KLA peptides (KLAKLAKKLAKLAK) and gentamicin in the targeted therapy of anti-microbial resistant Klebsiella pneumoniae (K. pneumonia) lung infection. METHODS: The characteristics of KLA-neutrophils nanoparticles (NNPs) are identified via dynamic light scattering (DLS), transmission electron microscope (TEM), SDS-PAGE, Western blot, quantitative flow cytometry (QFCM) and confocal microscopy. The safety of KLA-NNPs both in vitro and in vivo is evaluated by hemolysis test, platelet α granule membrane protein concentration, protein adsorption capacity, in vitro macrophage phagocytosis, weight change, liver function indicators, blood biochemical indicators, and pathological changes of vital organs in mice. The efficacy of KLA-NNPs is determined by time-kill assay, fluorescent label test, intracellular bacterial content, caspase-1 activity, survival rate, and HE staining both in vitro and in vivo. RESULTS: The prepared KLA-NNPs have a typical "core-shell" structure, uniform nanometer size, and retain the membrane proteins on the neutrophil membrane that achieve functional effects. In vitro safety analysis showed that KLA-NNPs have good blood compatibility and can inhibit macrophage phagocytosis in vitro. KLA-NNPs can effectively release KLA and significantly reduce intracellular bacteria and caspase-1 activity. In vivo safety analysis and efficacy analysis revealed that KLA-NNPs have good biocompatibility and could effectively improve the survival rate of mice. CONCLUSION: The prepared KLA-NNPs have good nano-medicine chemical and physical properties and safety. It can evade immune system clearance, achieve high-efficiency targeted aggregation and drug delivery to bacterial infection sites, and effectively inhibit the development of pneumonia induced by drug-resistant K. pneumonia.

The flavors of edible mushrooms: A comprehensive review of volatile organic compounds and their analytical methods.

Due to their distinctive flavors, edible mushrooms have gained attention in flavor-related research, and the quality of their flavors determines their consumption. The odor is a vital element of food flavor that significantly impacts consumers' perceptions and purchase decisions. The volatile organic compounds (VOCs) of the odorant ingredient is the primary factors affecting scent characteristics. VOCs analysis and identification require technical assistance. The production and use of edible mushrooms can be aided by a broader examination of their volatile constituents. This review discusses the composition of VOCs in edible mushrooms and how they affect flavors. The principles, advantages, and disadvantages of various methods for extraction, isolation, and characterization of the VOCs of edible mushrooms are also highlighted. The numerous VOCs found in edible mushrooms such as primarily C-8 compounds, organic sulfur compounds, aldehydes, ketones, alcohols, and esters are summarized along with their effects on the various characteristics of scent. Combining multiple extraction, isolation, identification, and quantification technologies will facilitate rapid and accurate analysis of VOCs in edible mushrooms as proof of sensory attributes and quality.

Polypyrrole/Schiff Base Composite as Electromagnetic Absorbing Material with High and Tunable Absorption Performance.

In recent years, Schiff base-related conjugated systems have received extensive attention, but little research has been done in the field of electromagnetic materials. In this work, an organic conjugated system based on polypyrrole/hydrazone Schiff base (PPy/HSB) composites was constructed via a Schiff base synthetic route and their electromagnetic behavior was investigated. The electromagnetic response of PPy/HSB complexes demonstrates fine electromagnetic absorption performance. When the filler loading is 30 wt% in a paraffin matrix, an absorption peak of -43.1 dB was achieved and its effective absorption bandwidth (EAB) was located in the range of 10.88-18.0 GHz. The electromagnetic response behavior of PPy/HSB complexes is explained by models involving electronic structure, multi-polarization and conductive network. The mechanisms of PPy/HSB complexes formation and HSB crystallization are also discussed through the compatibility of PPy/HSB and the structure of HSB. Moreover, the morphology transformation of HSB in the PPy/HSB systems has been studied. This study opens the exploration of organic-dielectric conjugated systems in the field of electromagnetic materials, and significantly broadens the application range of organic-dielectric-dielectric composites.

Baicalin protects against renal interstitial fibrosis in mice by inhibiting the TGF-ß/Smad signalling pathway.

CONTEXT: Baicalin, a flavonoid extracted from radix scutellariae, possesses various pharmacological effects, including protective effects on renal interstitial fibrosis (RIF), but its possible role and mechanisms have not been fully elucidated. OBJECTIVE: This study explores the protective effects and mechanisms of baicalin on RIF. MATERIALS AND METHODS: C57BL/6 male mice were divided into six groups: sham, model, low baicalin, middle baicalin, high baicalin and positive drug groups. The unilateral ureteral obstruction (UUO) model of RIF was constructed and treated with baicalin doses (10, 20 and 40 mg/kg) and a positive control drug (valsartan, 8 mg/kg). H&E staining was used to observe the pathological changes in renal tissues, Masson staining was performed to evaluate collagen deposition in renal tissues, and immunohistochemical examination was adopted to determine α-SMA and extracellular matrix (ECM) expression. Primary mouse fibroblasts were isolated, extracted and treated with baicalin and/or TGF-ß. qRT-PCR and enzyme-linked immunosorbent assay (ELISA) were applied to detect the inflammatory responses. Moreover, ECM and TGF-ß/Smad expression levels were evaluated by western blot assay. RESULTS: Baicalin ameliorated RIF in UUO mice by inhibiting fibrosis and inflammatory responses. The TGF-ß/Smad pathway was significantly suppressed in the UUO mouse model. Additionally, baicalin significantly inhibited ECM expression and inflammatory factors in fibroblasts treated with TGF-ß. TGF-ß/Smad pathway activation was significantly decreased in fibroblasts. DISCUSSION AND CONCLUSIONS: These findings support the use of baicalin as a potential therapeutic option for the treatment of RIF by possibly inhibiting the TGF-ß/Smad signalling pathway.

Hydrogen Bonding Promoted Tautomerism between Azo and Hydrazone Forms in Calcon with Multistimuli Responsiveness and Biocompatibility.

Realization of multistimuli responsiveness in one molecule remains a challenge due to the difficulty in understanding and control of comprehensive interplay between the external stimuli and the subtle conformation changes. The coexistence of dynamic bonding interactions, hydroxyl group, and the azo chromophore in calcon causes the multistimuli responsiveness to external stimuli including temperature, pH variation, and light irradiation. Density functional theory (DFT), time-dependent DFT (TDDFT), and various molecular dynamics (MD) simulations are employed to systematically investigate the azo-hydrazone tautomerism and E-to- Z isomerization. The inter/intramolecular hydrogen bonding interactions promote the azo-hydrazone tautomerism at different pH conditions. The strong n → π* absorption in the visible light region gives an advantage of calcon without the harm to living cells from UV light. The facial tautomerism renders the calcon temperature sensitivity, which could be triggered at body temperature (311 K) with distinct color change from red to blue. It is also found that in pH = 6.8 both azo and hydrazone isomers have no cytotoxicity on the human lung cells (A549 and H1299) and hepatic epithelial cell of rat (FL83B). The visible-light absorption, pH, and temperature sensitiveness and biocompatibility render calcon potential candidates for biomedical applications.

[A new guaiane-type sesquiterpenoid from Croton yunnanensis].

Five sesquiterpenoids were isolated from 90% ethanol extract of Croton yunnanensis by silica gel,Sephadex LH-20 column chromatography,as well as prep-HPLC methods. Based on MS,1 D and 2 D NMR spectral analyses,the structures of the five compounds were identified as 11-methoxyl alismol(1),6ß,7ß-epoxy-4α-hydroxyguaian-10-ene(orientalol C,2),multisalactone D(3),arvestonol(4),and 4,5-dihydroblumenol A(5). Compound 1 was a new guaiane-type sesquiterpenoid. Compounds 2-4 were isolated from the Croton genus for the first time,and compound 5 was obtained from this plant for the first time.

CBN: Constructing a clinical Bayesian network based on data from the electronic medical record.

The process of learning candidate causal relationships involving diseases and symptoms from electronic medical records (EMRs) is the first step towards learning models that perform diagnostic inference directly from real healthcare data. However, the existing diagnostic inference systems rely on knowledge bases such as ontology that are manually compiled through a labour-intensive process or automatically derived using simple pairwise statistics. We explore CBN, a Clinical Bayesian Network construction for medical ontology probabilistic inference, to learn high-quality Bayesian topology and complete ontology directly from EMRs. Specifically, we first extract medical entity relationships from over 10,000 deidentified patient records and adopt the odds ratio (OR value) calculation and the K2 greedy algorithm to automatically construct a Bayesian topology. Then, Bayesian estimation is used for the probability distribution. Finally, we employ a Bayesian network to complete the causal relationship and probability distribution of ontology to enhance the ontology inference capability. By evaluating the learned topology versus the expert opinions of physicians and entropy calculations and by calculating the ontology-based diagnosis classification, our study demonstrates that the direct and automated construction of a high-quality health topology and ontology from medical records is feasible. Our results are reproducible, and we will release the source code and CN-Stroke knowledge graph of this work after publication.1.

Circulating miR-208b: A Potentially Sensitive and Reliable Biomarker for the Diagnosis and Prognosis of Acute Myocardial Infarction.

BACKGROUND: MicroRNAs are present in human plasma and have been reported to be biomarkers for cardiovascular diseases. The aim of this study was to investigate the value of circulating microRNA-208b (miR-208b) for the diagnosis and prognosis of acute myocardial infarction (AMI). METHODS: A total of 100 AMI patients, 80 unstable angina (UA) patients, and 80 healthy controls (HCs) were consecutively included in this study. Plasma was collected from each participant on admission, and the levels of circulating miR-208b were measured using reverse transcription-polymerase chain reaction (RT-PCR). The AMI patients who underwent percutaneous coronary intervention (PCI) were followed up at 6 months post-AMI. RESULTS: The concentration of miR-208b was higher in the AMI patients than in the other two groups (p < 0.05), and it was positively correlated with the levels of creatine kinase (CK)-MB and cardiac troponin I (cTnI) (p < 0.01). Moreover, the receiver operating characteristic (ROC) curves showed that miR-208b was sensitive like CK-MB and cTnI for the diagnosis of AMI. In addition, the miR-208b concentration in AMI patients with threevessel coronary artery disease (CAD) was higher than that of single- or two-vessel CAD AMI patients (p < 0.05). Also, the miR-208b expression after PCI was significantly lower than on admission (p < 0.01). Furthermore, miR208b expression in AMI patients with left ventricular remodeling/MACEs was higher than in those without after PCI (p < 0.05). CONCLUSIONS: Circulating miR-208b may serve as a sensitive biomarker for the diagnosis and prognosis of AMI patients.

Increased Mean Platelet Volume is Associated with Higher In-Hospital Mortality Rate in Patients with Acute Myocardial Infarction.

BACKGROUND: To evaluate the prognostic value of mean platelet volume (MPV) on admission for the in-hospital mortality in patients with acute myocardial infarction (AMI). METHODS: Medical records of 567 AMI patients were retrospectively reviewed, and their baseline clinical and laboratory characteristics were extracted. The relationships between the MPV and both clinical and laboratory characteristics were analyzed. The predictive value of the MPV for in-hospital death was estimated using receiver operating characteristic (ROC) curve analysis and a multivariate logistic regression model. RESULTS: The area under the curve (AUC) of MPV for in-hospital death was 0.77 (95% CI: 0.72 - 0.82). At a threshold of 12.5 fL, the sensitivity and specificity of MPV for in-hospital death were 0.58 (95% confidence interval (CI): 0.48 - 0.67) and 0.88 (95% CI: 0.84 - 0.91), respectively. In a multivariable logistic regression model, MPV > 12.5 fL was an independent risk factor for in-hospital mortality, with an odds ratio (OR) of 5.35 (95% CI, 3.03 - 9.45). CONCLUSIONS: Increased MPV is associated with higher in-hospital mortality rate in patients with AMI.

Diagnostic and Prognostic Value of Circulating MicroRNA-133a in Patients with Acute Myocardial Infarction.

BACKGROUND: The aim of this study was to examine the expression of circulating microRNA (miR)-133a in acute myocardial infarction (AMI) patients and assess its potential as a diagnostic and prognostic marker. METHODS: This study enrolled 222 consecutive patients who presented with chest pain symptoms suggestive of AMI in either the Department of Emergency or Department of Cardiology at Wuxi Second People's Hospital from October 2012 through December 2014. Of these, 102 were diagnosed with AMI and 120 with non-AMI chest pain. An additional 110 healthy individuals who received physical examinations in the same hospital during the same period were used as controls. RESULTS: MiR-133a expression was significantly elevated in the AMI patients compared to both non-AMI patients and healthy controls (p < 0.01 for both). MiR-133a levels were markedly increased in AMI patients within 2 hours after the onset of chest pain and remained elevated over the next 9 hours. MiR-133a concentration at 24 hours after percutaneous coronary intervention (PCI) was significantly lower compared to time of admission in the emergency PCI group (p < 0.01). The elevation in miR-133a was specific and sensitive for the diagnosis of AMI, with an optimal cutoff value of 0.87 (95% confidence interval (CI), 0.812 - 0.928). Kaplan-Meier analysis demonstrated that major adverse cardiovascular events occurred significantly more often in AMI patients who had miR-133a levels above the median (p < 0.01). CONCLUSIONS: Elevated levels of circulating miR-133a were strongly associated with AMI diagnosis. The concentration of miR-133a may provide prognostic information additive to traditional markers for clinical prognosis in AMI patients.

Effect of AlCl3 concentration on nanoparticle removal by coagulation.

In recent years, engineered nanoparticles, as a new group of contaminants emerging in natural water, have been given more attention. In order to understand the behavior of nanoparticles in the conventional water treatment process, three kinds of nanoparticle suspensions, namely multi-walled carbon nanotube-humic acid (MWCNT-HA), multi-walled carbon nanotube-N,N-dimethylformamide (MWCNT-DMF) and nanoTiO2-humic acid (TiO2-HA) were employed to investigate their coagulation removal efficiencies with varying aluminum chloride (AlCl3) concentrations. Results showed that nanoparticle removal rate curves had a reverse "U" shape with increasing concentration of aluminum ion (Al(3+)). More than 90% of nanoparticles could be effectively removed by an appropriate Al(3+) concentration. At higher Al(3+) concentration, nanoparticles would be restabilized. The hydrodynamic particle size of nanoparticles was found to be the crucial factor influencing the effective concentration range (ECR) of Al(3+) for nanoparticle removal. The ECR of Al(3+) followed the order MWCNT-DMF>MWCNT-HA>TiO2-HA, which is the reverse of the nanoparticle size trend. At a given concentration, smaller nanoparticles carry more surface charges, and thus consume more coagulants for neutralization. Therefore, over-saturation occurred at relatively higher Al(3+) concentration and a wider ECR was obtained. The ECR became broader with increasing pH because of the smaller hydrodynamic particle size of nanoparticles at higher pH values. A high ionic strength of NaCl can also widen the ECR due to its strong potential to compress the electric double layer. It was concluded that it is important to adjust the dose of Al(3+) in the ECR for nanoparticle removal in water treatment.

Copper-catalyzed aerobic oxidative cleavage of C-C bonds in epoxides leading to aryl ketones.

A novel copper-catalyzed aerobic synthesis of ketones from epoxides via cleavage of C-C single bonds has been discovered. This reaction constitutes a new transformation from epoxides into ketones.

Detrimental effects of metronidazole on selected innate immunological indicators in common carp (Cyprinus carpio L.).

The widely used antibiotic metronidazole (MTZ) was investigated for its toxic effects on the innate immunity in common carp (Cyprinus carpio L.). The fish were exposed to MTZ at nominal concentrations of 0.1, 0.5, and 2.5 mg L(-1) in water for 30 days, followed by a 5-days of cleanout period, after which certain innate immunity parameters were measured. The results showed that under the tested concentrations, MTZ-exposed fish exhibited decline in several humoral and cellular parameters, including complement activity, lysozyme activity, bactericidal activity, total serum protein levels, total WBC count, and the respiratory burst activity of kidney leukocytes. Except for total serum proteins, all of these parameters showed a significant difference in the 2.5 mg L(-1) MTZ group compared to control group (p < 0.05). The results clearly support the contention that MTZ suppresses the innate immunity of common carp.

Base-assisted transmetalation enables gold-catalyzed oxidative Sonogashira coupling reaction.

The traditional transition metal catalyzed neutral C(sp)-C(sp2) cross-coupling reaction between a nucleophile and an electrophile is a key technique for the formation of carbon-carbon bonds. Herein, we present a general gold-catalyzed oxidative Sonogashira cross-coupling of arylboronic acids and terminal arylalkynes at room temperature with excellent functional-group tolerance and good chemoselectivity. Moreover, our mechanistic studies suggested a third pathway involving a base-assisted transmetalation between the gold(I) catalyst and aryl boronic acid might predominate in our reaction conditions, rather than the previously assumed oxidation of the gold(I) complex or deprotonation of alkynes.

Electrochemical-Induced C-N Bond Formation: A New Method to Synthesis (Z)-Quinazolinone Oximes Using Primary Amines and Quinazolin-4(3H)-one.

A novel and highly selective electrochemical method for the synthesis of diverse quinazolinone oximes via direct electrooxidation of primary amines/C(sp2)-H functionalization of oximes has been developed. The reaction is conducted in an undivided cell under constant current conditions and is oxidant-free, open-air, and eco-friendly. Notably, the protocol shows good functional group tolerance, providing versatile quinazolinone oximes in good yields. Moreover, the mechanism is investigated through control experiments and cyclic voltammogram (CV) experiments.

Exploration of Antimicrobial Peptides in the Treatment of Gentamicin-Resistant Klebsiella pneumoniae Infection.

Introduction: The emergence of multidrug-resistant Klebsiella pneumoniae (K. pneumoniae) and the decline of effective antibiotics lead to the urgent need for new antibacterial agents. The aim of this study is to investigate the therapeutic effect of antimicrobial peptides against gentamicin-resistant (RT) K. pneumoniae and to screen effective antimicrobial peptides. Methods: In this study, the RT strains were induced by gradient gentamicin, and the RT strains were selected by detecting the expression levels of efflux pump genes, porin genes, and biofilm formation genes of the strains combined with their effects on the cells. Then the effects of four antimicrobial peptides on the efflux pump activity, biofilm formation level and cell condition after infection were detected to explore the effects of antimicrobial peptides on RT strains. Finally, the RT strain was used to induce a mouse model of pneumonia, and the four antimicrobial peptides were used to treat pneumonia mice for in vivo experiments. The pathological changes in lung tissues in each group were detected to explore the antimicrobial peptide with the most significant effect on the RT strain in vivo. Results: The results showed that the minimal inhibitory concentrations of the RT strains (strain C and strain I) were significantly higher than those of the wild-type strain, and the expression of efflux pump, porin and biofilm formation genes was significantly increased. The antimicrobial peptides could effectively inhibit the biofilm formation and efflux pump protein function of the RT strains. In addition, the antimicrobial peptides showed promising antibacterial effects both in vitro and in vivo. Discussion: Our study provided a theoretical basis for the treatment of gentamicin resistant K. pneumoniae infection with antimicrobial peptides, and found that KLA was significantly superior to LL37, Magainin I, KLA and Dermaseptin (10 µg/mL in cells, 50 µg in mice).

Hemilabile P,N-Ligand-Assisted Gold-Catalyzed Heck Reaction of Aryl and Styryl Iodides with Styrenes.

A gold-catalyzed Heck reaction of aryl and styryl iodides with styrenes was developed. The hemilabile P,N-ligand-assisted gold-catalyzed C(sp2)-C(sp2) cross-coupling can synthesize stilbenes and bistyryl complexes, with good functional-group tolerance and mild conditions. The elementary organometallic steps of migratory insertion and ß-hydride elimination might be involved in this ligand-enabled Au(I)/Au(III)-catalyzed Heck reaction with styrenes.

A borate-based peroxynitrite fluorescent probe and its application in fluorescence imaging of living cells.

As a bioactive species with high oxidation capacity, peroxynitrite (ONOO-) plays a crucial role in the regulation of diverse pathophysiological processes, and the overproduction of ONOO- is closely associated with various physiological diseases such as liver injury, pulmonary fibrosis and so on. Herein, two borate-based fluorescent probes 3a and 3b were synthesized for monitoring ONOO- by a simple substitution reaction. The experimental results showed that 3a and 3b had high selectivity and sensitivity for ONOO-. The detection limits of 3a and 3b were 79.46 nM and 32.12 nM, respectively. Moreover, the recognition was not disturbed by other active oxygen groups and common ions. More importantly, the probes 3a and 3b had low cytotoxicity and were successfully used to detect endogenous and exogenous ONOO-. They would provide an efficient detection method for further exploring the physiological and pathological role of ONOO- in complex biological systems and related diseases.