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MXene quantum dots (MQDs), an emerging zero‐dimensional nanomaterial, have garnered significant attention from researchers due to their distinctive physical and chemical properties. In this study, cysteine‐functionalized Ti3C2 MQDs were synthesized using a facile hydrothermal methods, resulting in the functionalized Ti3C2 MQDs exhibiting intense blue fluorescence attributed to size‐dependent effects and surface defects. Furthermore, the cysteine‐functionalized Ti3C2 MQDs exhibit excitation wavelength‐dependent emission behavior and serve as a highly sensitive fluorescent probe for Ag+ detection with an impressive low limit of detection (LOD) of 0.015 μM. Moreover, they demonstrate exceptional sensitivity and selectivity in determining Ag+. This study presents a novel approach for the detection of Ag+ and highlights the immense potential of cysteine‐functionalized Ti3C2 MQDs in environmental applications. [ABSTRACT FROM AUTHOR]

Controlling the nanoparticle‐cell membrane interaction to achieve easy and fast membrane anchoring and cellular internalization is of great importance in a variety of biomedical applications. Here we report a simple and versatile strategy to maneuver the nanoparticle‐cell membrane interaction by creating a tunable hydrophobic protrusion on Janus particles through swelling‐induced symmetry breaking. When the Janus particle contacts cell membrane, the protrusion will induce membrane wrapping, leading the particles to docking to the membrane, followed by drawing the whole particles into the cell. The efficiencies of both membrane anchoring and cellular internalization can be promoted by optimizing the size of the protrusion. In vitro, the Janus particles can quickly anchor to the cell membrane in 1 h and be internalized within 24 h, regardless of the types of cells involved. In vivo, the Janus particles can effectively anchor to the brain and skin tissues to provide a high retention in these tissues after intracerebroventricular, intrahippocampal, or subcutaneous injection. This strategy involving the creation of a hydrophobic protrusion on Janus particles to tune the cell‐membrane interaction holds great potential in nanoparticle‐based biomedical applications. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) features the loss of cholinergic neurons in the mesopontine area. There is no available approach to repair the damaged cholinergic neurons. Neural stem cell (NSC)‐based therapy is a promising strategy for the treatment of AD. However, it is a challenge to direct the NSCs to specifically differentiate into cholinergic neurons. Herein, calcium folate (CaFO) nanoparticles are synthesized through a facile nanoprecipitation approach for promoting the differentiation of NSCs into functional cholinergic neurons. After uptake by NSCs, the CaFO nanoparticles are distributed in the lysosomes (pH< 5.5) and can be decomposed into Ca2+ and folic acid in the acidic environment. The Ca2+ can accelerate the differentiation rate of NSCs while the folic acid can direct the NSCs to differentiate into cholinergic neurons. The in vitro experiments demonstrate that under the stimulation of CaFO nanoparticles, the NSCs differentiate into functional cholinergic neurons within 5 d. Animal experiments prove that the CaFO nanoparticles also promote the neuronal differentiation of NSCs in vivo, leading to the improvement in the cognitive memory ability of AD mice. This study provides a new strategy to induce the quick differentiation of NSCs into functional cholinergic neurons, which is promising for the treatment of AD. [ABSTRACT FROM AUTHOR]

An electrochemical sensor based on carbon quantum dots@hexagonal boron nitride nanosheets nanocomposites (CQDs@HBNNS‐NCs) and molecularly imprinted polymer (MIP) was proposed for the triclosan (TCS) analysis. The CQDs@HBNNS‐NCs were utilized as the modifier, which exhibited excellent electrochemical properties. The MIP film was prepared in situ in the presence of template (TCS) and monomer (o‐phenylenediamine) to provide the specific molecular recognition. The CQDs@HBNNS‐NCs were characterized by transmission electron microscopy (TEM), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimal conditions, the current response was linear with the logarithmic value of TCS concentration in the range of 2 nM–0.1 mM, and the limit of detection (LOD) was calculated as 0.005 μM (S/N=3). Furthermore, the proposed electrochemical sensor showed favorable selectivity, stability, and was used for the TCS analysis in tap water samples with decent accuracy. [ABSTRACT FROM AUTHOR]

Polyion complex (PIC) vesicles have attracted considerable attention as soft yet functional delivery vehicles. However, most of the PIC vesicles suffer from insufficient stability and functionality which hinder their applications. Herein, a new type of PIC vesicles obtained by co‐assembly of neutral‐cationic diblock copolymers with a supramolecular coordination polyelectrolyte is reported. The latter exhibits tunable structures and properties that endows regulated stability and functionalities of the vesicles. With lanthanide‐based coordination polymers, PIC vesicles are constructed with not only enhanced stability against salt, but also tunable fluorescent or magnetic properties associated with particular Ln3+ ions. Moreover, the vesicle lumen is applied to load PEGlated indocyanine green as a model photothermal transduction agent. The designed vesicles finally display high stability, good biocompatibility, and efficient photothermal conversion, and therefore behave well for thermal ablation of both tumor cells and tumor in mice. The well‐regulated stability and functions of the PIC vesicles are assigned the adaptive structure and properties of the supramolecular coordination polyelectrolytes, which hardly be achieved with conventional covalent polyelectrolytes. This study therefore demonstrates a facile strategy to regulate the stability and function of PIC vesicles, and shall be inspirational for developing novel vesicular materials for potential biomedical applications. [ABSTRACT FROM AUTHOR]

Aim: To explore the experiences of patients with cancers in hospitals during the COVID‐19 pandemic. Design: A qualitative research study. Methods: Using a phenomenological approach, we enrolled 22 patients with cancers in the Hunan Cancer Hospital from 20 February 2020 to 10 April 2020. The interviews were conducted face‐to‐face and were analysed by Colaizzi's 7‐step method. This study aligns with the COREQ checklist. Results: The experiences of patients with cancers in hospitals during the COVID‐19 pandemic can be categorized into four major themes: (1) emotional changes; (2) delays in visiting hospital; (3) barriers to accessing medical care services, and (4) inconvenience related to logistics services. [ABSTRACT FROM AUTHOR]

Cysteine‐functionalized Fe3O4 magnetic nanoparticles were synthesized by thiol‐ene click reaction and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier‐transform infrared spectroscopy (FT‐IR), X‐ray diffraction spectrometry (XRD), thermal gravimetric analysis (TGA), vibrating sample magnetometer (VSM), X‐ray photoelectron spectroscopy (XPS), specific surface area (BET) analysis and pore size distribution analysis. The obtained magnetic materials were employed as a magnetic solid phase extraction adsorbent combined with inductively coupled plasma‐atomic emission spectrometry (ICP‐AES) for determination of Cu2+. Several parameters affecting extraction efficiency, including eluent concentration, adsorption time, adsorbent amounts, and sample pH were investigated. Under the optimized conditions, the method was validated. Within the concentration range of 0.01–20 μg mL−1, The limit of detection (LOD) and the limit of quantification (LOQ) were determined to be 0.002 μg mL−1 and 0.007 μg mL−1, respectively. The adsorption percentage of Cu2+ ions remained above 87.0 % when the adsorption‐desorption data of Cu2+ ions through three cycles of the successive adsorption and desorption process. The results show that a reliable and rapid method was established for determination of Cu2+ ions. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a debilitating neurodegenerative disorder characterized by dopaminergic neuron degeneration. Neural stem cell (NSC) therapy offers promise for replacing these neurons and restoring neural function. However, directing NSCs to become dopaminergic neurons is challenging. Retinoic acid (RA) is a potential regulator, but its insolubility in water limits its use in PD therapy. Herein, nanonizing RA with calcium acetate to create calcium‐retinoic acid nanoparticles (Ca‐RA NPs) is proposed. These nanoparticles can be internalized by NSCs and then dissociated in the acidic environment of lysosomes to lead to a burst of Ca2+ and RA. In vitro results showed that the intracellular bursting of Ca2+ and RA accelerated neuronal differentiation and maturation by 5–10 days compared to spontaneous NSC differentiation. Importantly, Ca‐RA NPs uniquely directed NSCs to dopaminergic neurons, involving the interaction between the calcium ion‐mediated MAPK signaling pathway and the RA‐mediated RA signaling pathway. Animal experiments further validated the efficacy of Ca‐RA‐coated NSCs in restoring motor and cognitive functions in PD mice by rapidly forming dopaminergic neural circuits. Given that both RA and calcium acetate are approved by the FDA, this strategy has the potential for translation into a clinical treatment approach for stem cell therapy of PD. [ABSTRACT FROM AUTHOR]

The cleavage of C−O linkages in aryl ethers in biomass‐derived lignin compounds without hydrogenation of the aromatic rings is a major challenge for the production of sustainable mono‐aromatics. Conventional strategies over the heterogeneous metal catalysts require the addition of homogeneous base additives causing environmental problems. Herein, we propose a heterogeneous Ru/C catalyst modified by Br atoms for the selective direct cleavage of C−O bonds in diphenyl ether without hydrogenation of aromatic rings reaching the yield of benzene and phenol as high as 90.3 % and increased selectivity to mono‐aromatics (97.3 vs. 46.2 % for initial Ru) during depolymerization of lignin. Characterization of the catalyst indicates selective poisoning by Br of terrace sites over Ru nanoparticles, which are active in the hydrogenation of aromatic rings, while the defect sites on the edges and corners remain available and provide higher intrinsic activity in the C−O bond cleavage. [ABSTRACT FROM AUTHOR]

Polyelectrolyte complex nanoparticles with integrated advances of coacervate complexes and nanomaterials have attracted considerable attention as soft templates and functional nano‐carriers. Herein, a facile and robust strategy, namely electrostatic assembly directed polymerization (EADP), for efficient and scalable preparation of stable coacervate nanoparticles is presented. With homo‐polyelectrolyte PAA (polyacrylic acid) as template and out of charge stoichiometry, the cationic monomers are polymerized together with cross‐linkers, which creates coacervate nanoparticles featuring high stability against salt through one‐pot synthesis. The particle size can be tuned by varying the cross‐linker amount and salt concentrations during the polymerization and the composition of nanoparticles, as well as the corresponding properties can be regulated by combining different charged blocks from both strong and weak ionic monomers. The strategy can tolerate both high monomer concentrations and increased volume of up to l L, which is favorable for scaled‐up preparations. Moreover, the coacervate nanoparticles can be freeze‐dried to produce a product in powder form, which can be redispersed without any effect on the particle size and size distribution. Finally, the obtained nanoparticles loaded with enzyme and Au nanoparticles exhibit enhanced catalytic performance, demonstrating a great potential for exploring various applications of coacervate particles as soft and functional nano‐carriers. [ABSTRACT FROM AUTHOR]

The selective oxidation of alcohols to corresponding aldehydes is one of the most challenging problems in modern chemistry due to over‐oxidation of these products further into corresponding acids and esters. Herein, we report an efficient and eco‐friendly method for selective oxidation of aliphatic, unsaturated and aromatic alcohols to aldehydes (>90 %) using small size (2 nm) non‐supported colloidal Ru nanoparticles. The selectivity rapidly decreases with increase of the size of nanoparticles (from 2 to 10 nm) or after their deposition over support. X‐ray photoelectron spectroscopy suggests that this catalytic performance can be attributed to high content Ru−O species on the surface of small size Ru nanoparticles, which undergo reduction with formation of water and aldehyde and easy oxidation cycles during the reaction according to the Mars‐van Krevelen mechanism. The presence of surface oxide layer over small size Ru nanoparticles suppresses over‐oxidation of aldehydes to acids. [ABSTRACT FROM AUTHOR]

Reported here is a new class of PICsomes (vesicles formed by polyelectrolyte complexation) in which the anionic/neutral diblock copolymer is replaced by an anionic, reversible, supramolecular polyelectrolyte based on metal–ligand coordination. This supramolecular polyelectrolyte forms exclusively inside the wall of the assembly, and therefore self‐adjusts its length to that of the cationic block provided. Moreover, the supramolecular coordination polyelectrolytes introduce new and tunable properties and functions associated with the specific metal. As a proof‐of‐concept Mn‐based PICsomes were prepared and display high magnetic relaxivity, as well as enhanced contrast in in vitro magnetic resonance imaging tests. The simplicity of our approach, together with the new functions derived from the metal ions, demonstrates a robust strategy for the preparation of a variety of PICsomes with well‐defined and tunable structures and properties. [ABSTRACT FROM AUTHOR]

Background and objective: Periodontitis is a chronic inflammatory disease characterized by the destruction of the periodontium. The strontium ion (Sr2+) can prevent the bone loss associated with periodontitis and promote the regeneration of the bone. The mechanisms by which the Sr2+ works remain poorly understood. We aim to investigate the effects of the Sr2+ ion on cell proliferation, inflammatory regulation and osteogenic differentiation of human periodontal ligament cells (hPDLCs) in pathological conditions. Material and methods: hPDLCs were obtained from premolars that came from the orthodontic extraction. The hPDLCs were treated with Sr2+ and/or lipopolysaccharide (LPS), which was applied as the pathological condition of periodontitis. The effect of the dose of Sr2+ on cell proliferation was analyzed using a Cell Counting Kit‐8 assay. The gene and protein expression of proinflammatory cytokines were detected by the real‐time polymerase chain reaction and enzyme‐linked immunosorbent assay. The osteogenic differentiation and mineralization were assessed by the real‐time polymerase chain reaction, alkaline phosphatase activity assay and alizarin red staining. Results: Results demonstrated that Sr2+ in a range of concentrations from 0.02 to 2.5 mmol/L significantly improved the proliferation of hPDLCs. Sr2+ reversed LPS‐stimulated proinflammatory cytokine expressions such as tumor necrosis factor alpha, interleukin (IL)‐1β, IL‐6 and IL‐8. Moreover, Sr2+ rescued the LPS‐inhibited gene expression of osteogenic differentiation. Although it appeared to suppress the late mineralization, Sr2+ can reverse the LPS‐inhibited early osteogenic differentiation of hPDLCs. Conclusion: These results indicated that Sr2+ could attenuate the LPS‐stimulated proinflammatory molecule expression and inhibit early osteogenic differentiation of hPDLCs. [ABSTRACT FROM AUTHOR]

Abstract: Three‐component mixtures (diblock copolymer/metal ion/oligoligand) can assemble into micellar particles owing to a combination of supramolecular polymerization and electrostatic complex formation. Such particles cover a large range of compositions, but the electrostatic forces keeping them together make them rather susceptible to disintegration by added salt. Now it is shown how the salt stability can be tuned continuously by employing both a bis‐ligand and a tris‐ligand, and varying the ratio of these in the mixture. For magnetic ions such as MnII and FeIII, the choice of the multiligand also affects the ion/water interaction and, hence, the magnetic relaxivity. As an example, MnII‐based nanoparticles with a very high longitudinal relaxivity (10.8 m m−1 s−1) were investigated that are not only biocompatible but also feature strong contrast enhancement in target organs (liver, kidney), as shown by T1‐weighted in vivo magnetic resonance imaging (MRI). [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was to perform a histomorphometric evaluation of the healing characteristics and jawbone remodeling processes in the peri-implant bone tissue of three commonly used implant surfaces, during the early weeks of osseointegration. Material and methods Dental implants with three different surfaces (anodically modified, hydroxyapatite ( HA)-coated and machined) were inserted into the mandibular side-tooth region of twelve adult mini-pigs. Histomorphometric analyses were performed to evaluate remodeling processes 3, 6 and 12 weeks post-implantation. Results Only a few very early bone remodeling-resorption sites were found at 3 weeks. After 6 weeks, additional signs of remodeling-related reversal and bone formation were detectable in all three groups, which steadily increased until 12 weeks. At the latter time point, the amount of remodeled bone was significantly higher for the anodized and HA-coated surfaces than for the machined implants. Conclusion The results of this study demonstrate that peri-implant bone remodeling can start as early as 3 weeks after implantation and continues at a substantial level up to 12 weeks. The anodic modification or HA coating of implant surfaces appears to accelerate the conversion of primary regenerated bone into more mature secondary lamellar bone. If this observation is of clinical relevance, it has to be clarified in studies that include longer observational time periods. [ABSTRACT FROM AUTHOR]

The utilization of semiconductor quantum dots (QDs) as optical labels for biosensing and biorecognition has made substantial progress. However, the development of a suitable QD-based luminescent probe that is capable of detecting individual reactive oxygen species (ROS) represents a great challenge, mainly because the fluorescence of QDs is quenched by a wide variety of ROS. To overcome this limitation, a novel QD-based turn-on luminescent probe for the specific detection of .OH has been designed, and its application in monitoring the endogenous release of .OH species in living cells is demonstrated. Metal citrate complexes on the surfaces of the QDs can act as electron donors, injecting electrons into the LUMO of the QDs, while .OH can inject holes into the HOMO of the QDs. Accordingly, electron-hole pairs are produced, which could emit strong luminescence by electron-hole recombination. Importantly, this luminescent probe does not respond to other ROS. [ABSTRACT FROM AUTHOR]

In this study, we focused on measuring levels of nurse burnout and job dissatisfaction in the daily practice of nurses in Hunan province, China, analyzed factors related to nurse burnout and job dissatisfaction, and explored the relationship between them. Previous studies have shown a high level of burnout and job dissatisfaction among nurses worldwide. A cross-sectional survey of 1100 nurses was conducted. The nurses worked at 20 hospitals in 11 cities and counties throughout China's Hunan province. Nurse burnout was measured by the Maslach Burnout Inventory. Nurse-rated job dissatisfaction was described using a four point scale, and work environment was measured using the Nursing Work Index - Practice Environment Scale. The results showed that nurses had high burnout scores and were dissatisfied with their jobs. Staffing, work environment, and work hours were all significantly associated with nurse burnout and job dissatisfaction. Adequate staffing, improved work environment, and reasonable work hours are related to decreasing nurse burnout and job dissatisfaction. [ABSTRACT FROM AUTHOR]

Histone lysine-specific demethylase 1 (LSD1) is the first discovered and reported histone demethylase by Dr. Shi Yang's group in 2004. It is classified as a member of amine oxidase superfamily, the common feature of which is using the flavin adenine dinucleotide (FAD) as its cofactor. Since it is located in cell nucleus and acts as a histone methylation eraser, LSD1 specifically removes mono- or dimethylated histone H3 lysine 4 (H3K4) and H3 lysine 9 (H3K9) through formaldehyde-generating oxidation. It has been indicated that LSD1 and its downstream targets are involved in a wide range of biological courses, including embryonic development and tumor-cell growth and metastasis. LSD1 has been reported to be overexpressed in variety of tumors. Inactivating LSD1 or downregulating its expression inhibits cancer-cell development. LSD1 targeting inhibitors may represent a new insight in anticancer drug discovery. This review summarizes recent studies about LSD1 and mainly focuses on the basic physiological function of LSD1 and its involved mechanisms in pathophysiologic conditions, as well as the development of LSD1 inhibitors as potential anticancer therapeutic agents. [ABSTRACT FROM AUTHOR]

Purpose The aim of this project is to investigate the impact of diabetes mellitus and different glycemic control times on early osseointegration of dental implants by expression and significance of serum bone Gla protein ( BGP) and alkaline phosphatase ( ALP) levels in Zucker diabetic fatty ( ZDF) rats after implantation. Materials and Methods The animals were divided into three groups, each group with 11 rats and each rat with two dental implants (33 rats and 66 implants in total): group A, diabetic rats with dental implants (controls); group B, diabetic rats treated with insulin and implants placed simultaneously; and group C, diabetic rats treated with insulin until serum glucose at a constant level and then implants be placed. Levels of BGP and ALP in the serum were measured by enzyme-linked immunosorbent assay in each group. The software program SPSS (version 17.0 for Windows) was used to analyze all data; p < .05 was set as the level of statistical significance. Results At the 7th day, serum levels of BGP in group B and C were lower than that in group A ( p > 0.05). At the 14th day, serum levels of BGP in group C were significantly higher ( p < 0.05). After 30 days, compared with group A, the serum levels of BGP in group B and C seems to be lower. Compared with group A, the serum levels of ALP in group B and C were significantly higher, whereas the serum levels of ALP in group C seems to be higher than B ( p < 0.05). Conclusions The present results suggest that injection of delayed release microsphere of exenatide on ZDF rats can release exenatide at a steady rate and the blood glucose can be controlled at a constant level. Implant survival rates could be enhanced in DM subjects when blood plasma glucose level is under control; the serum levels of BGP in this study seems to have no relationship with local osseointegration, whereas the serum levels of ALP might offer insights into the activity of osseointegration around the implant surface. [ABSTRACT FROM AUTHOR]

MXene quantum dots (MQDs), an emerging zero‐dimensional nanomaterial, have garnered significant attention from researchers due to their distinctive physical and chemical properties. In this study, cysteine‐functionalized Ti3C2 MQDs were synthesized using a facile hydrothermal methods, resulting in the functionalized Ti3C2 MQDs exhibiting intense blue fluorescence attributed to size‐dependent effects and surface defects. Furthermore, the cysteine‐functionalized Ti3C2 MQDs exhibit excitation wavelength‐dependent emission behavior and serve as a highly sensitive fluorescent probe for Ag+ detection with an impressive low limit of detection (LOD) of 0.015 μM. Moreover, they demonstrate exceptional sensitivity and selectivity in determining Ag+. This study presents a novel approach for the detection of Ag+ and highlights the immense potential of cysteine‐functionalized Ti3C2 MQDs in environmental applications. [ABSTRACT FROM AUTHOR]

Presents a study which employed biochemical, molecular and cytogenetic methods to examined the characterization of a non-Robertsonian wheat-rye chromosome translocation in line WER-1-1. Information on the plant material examined in this study; Production of WER-1-1; Results of this study.

Review: 274 refs. [ABSTRACT FROM AUTHOR]

Cysteine‐functionalized Fe3O4 magnetic nanoparticles were synthesized by thiol‐ene click reaction and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier‐transform infrared spectroscopy (FT‐IR), X‐ray diffraction spectrometry (XRD), thermal gravimetric analysis (TGA), vibrating sample magnetometer (VSM), X‐ray photoelectron spectroscopy (XPS), specific surface area (BET) analysis and pore size distribution analysis. The obtained magnetic materials were employed as a magnetic solid phase extraction adsorbent combined with inductively coupled plasma‐atomic emission spectrometry (ICP‐AES) for determination of Cu2+. Several parameters affecting extraction efficiency, including eluent concentration, adsorption time, adsorbent amounts, and sample pH were investigated. Under the optimized conditions, the method was validated. Within the concentration range of 0.01–20 μg mL−1, The limit of detection (LOD) and the limit of quantification (LOQ) were determined to be 0.002 μg mL−1 and 0.007 μg mL−1, respectively. The adsorption percentage of Cu2+ ions remained above 87.0 % when the adsorption‐desorption data of Cu2+ ions through three cycles of the successive adsorption and desorption process. The results show that a reliable and rapid method was established for determination of Cu2+ ions. [ABSTRACT FROM AUTHOR]