Nanosheet-hydrogel composites: from preparation and fundamental properties to their promising applications.

Hydrogels are an important class of soft materials with elastic and intelligent properties. Nevertheless, these traditional hydrogels usually possess poor mechanical properties and limited functions, which greatly restrict their further applications. With the rapid development of nanotechnology, there have been significant advances in the design and fabrication of functional nanocomposite hydrogels with unique properties and functions. Among various materials, nanosheets with planar topography, large specific surface areas, and versatile physicochemical properties have attracted intense research interest. Herein, this review summarises the synthesis mechanisms, fundamental properties, and promising applications of nanosheet-incorporated hydrogels. In particular, how the nanosheet structure is applied to improve the overall performance of the hydrogel in each application is emphasized. Additionally, the current challenges and prospects are briefly discussed in this area. We expect that the combination of nanosheets and hydrogels can attract more researchers' interest and bring new opportunities in the future.

Recent advances in multi-mechanism design of crack-resistant hydrogels.

For conventional hydrogels, the phenomenon of crack generation and propagation caused by high-stress concentration is ubiquitous. However, this phenomenon is unfavorable in many applications, such as wearable electronics, tissue engineering, and tunable adhesion. Fortunately, many hydrogels that can suppress crack growth during deformation and maintain the original mechanical properties during deformation, called crack-resistant hydrogels, have been published. Herein, the state-of-the-art of crack-resistant hydrogels is comprehensively reviewed. Starting from the principle of designing a crack-resistant hydrogel, we first survey the relevant crack-resistant strategies. The latest crack-resistant hydrogels are then categorized according to their crack-resistant mechanisms (including energy dissipation at the molecular level, multiscale structure, crack pinning, crack deflection, and sliding of chain), and their crack-resistant processes are described in detail. Furthermore, we summarize the current challenges and make an outlook for crack-resistant hydrogels, which might lead to substantial progress in the future design and development of these high-performance materials.

Engineering the Stability of Nanozyme-Catalyzed Product for Colorimetric Logic Gate Operations.

Recently, the design and development of nanozyme-based logic gates have received much attention. In this work, by engineering the stability of the nanozyme-catalyzed product, we demonstrated that the chromogenic system of 3, 3', 5, 5'-tetramethylbenzidine (TMB) can act as a visual output signal for constructing various Boolean logic operations. Specifically, cerium oxide or ferroferric oxide-based nanozymes can catalyze the oxidation of colorless TMB to a blue color product (oxTMB). The blue-colored solution of oxTMB could become colorless by some reductants, including the reduced transition state of glucose oxidase and xanthine oxidase. As a result, by combining biocatalytic reactions, the color change of oxTMB could be controlled logically. In our logic systems, glucose oxidase, ß-galactosidase, and xanthine oxidase acted as inputs, and the state of oxTMB solution was used as an output. The logic operation produced a colored solution as the readout signal, which was easily distinguished with the naked eye. More importantly, the study of such a decolorization process allows the transformation of previously designed AND and OR logic gates into NAND and NOR gates. We propose that this work may push forward the design of novel nanozyme-based biological gates and help us further understand complex physiological pathways in living systems.

Global publication trends and research hotspots of the gut-liver axis in NAFLD: A bibliometric analysis.

Background: Nonalcoholic Fatty Liver Disease(NAFLD)refers to a spectrum of diseases ranging from simple liver steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis. Bidirectional cross-talk between the gut-liver axis plays an important role in the pathogenesis of NAFLD. To learn more about the gut-liver axis in NAFLD, this study aims to provide a comprehensive analysis from a bibliometric perspective. Method: Literature related to the gut-liver axis in NAFLD from 1989 to 2022 was extracted from the Web of Science Core Collection. Based on Microsoft Excel, CiteSpace and Vosviewer, we conducted to analyze the number of publications, countries/regions, institutions, authors, journals, references, and keywords. Results: A total of 1,891 literature since 2004 was included, with the rapid growth of the number of papers on the gut-liver axis in NAFLD annually. These publications were mainly from 66 countries and 442 institutions. Of the 638 authors analyzed, Bernd Schnabl was the one with the most publications, and Patrice D. Cani was the one with the most co-citations. International Journal of Molecular Sciences is the journal with the most articles published, and Hepatology is the journal with the most citations. The most common keywords are gut microbiota, inflammation, and insulin instance, which are current research hotspots. Short-chain fatty acid, in vitro, randomized controlled trial in clinical, and diabetes mellitus represent the research frontiers in this field and are in a stage of rapid development. Conclusion: This is the first study to conduct a comprehensive bibliometric analysis of publications related to the gut-liver axis in NAFLD. This study reveals that gut microbiota, inflammation, insulin resistance, short-chain fatty acids, and randomized controlled trial will be the hotspots and new trends in the gut-liver axis in NAFLD research, which could provide researchers with key research information in this field and is helpful for further exploration of new research directions.

Frontiers and hotspots of adipose tissue and NAFLD: a bibliometric analysis from 2002 to 2022.

Background: The annual incidence of non-alcoholic fatty liver disease (NAFLD) continues to rise steadily. In recent years, adipose tissue (AT) has gained recognition as a pivotal contributor to the pathogenesis of NAFLD. Employing bibliometric analysis, we examined literature concerning AT and NAFLD. Methods: Relevant literature on AT in NAFLD from 1980 to 2022 was extracted from the Web of Science Core Collection. These records were visualized using CiteSpace and VOSviewer regarding publications, countries/regions, institutions, authors, journals, references, and keywords. Results: Since 2002, a total of 3,330 papers have been included, exhibiting an annual surge in publications. Notably, the quality of publications is superior in the USA and Europe. Kenneth Cusi stands out as the author with the highest number of publications and H-index. Hepatology is the journal boasting the highest citation and H-index. The University of California System holds the highest centrality among institutions. References specifically delve into physiological processes associated with AT in NAFLD. Currently, lipid metabolism and inflammation constitute the principal research mechanisms in the AT-based regulation of NAFLD, with pertinent keywords including microRNA, T cell, hypoxia, sarcopenia, hepatokine, gut microbiota, and autophagy. The Mediterranean diet is among the most widely recommended dietary approaches for potential NAFLD treatment. Conclusion: This paper represents the inaugural bibliometric study on the effects of AT on NAFLD, offering valuable insights and directions for future research.

Recent advances in flexible and wearable chemo- and bio-sensors based on two-dimensional transition metal carbides and nitrides (MXenes).

Flexible and wearable devices have drawn great attention due to their promising applications from physiological signal detection to disease diagnosis. As a critical element of flexible and wearable devices, chemo- and bio-sensors have been widely merged with advanced nanomaterials. MXenes, a type of nanomaterial from the family of two-dimensional transition metal carbides, carbonitrides and nitrides, have been intensively explored in sensors, energy storage, electromagnetic interference shielding, biomedical engineering, and catalysis, owing to their fascinating structures and outstanding properties. In this review, we focus on recent advances in various flexible and wearable chemo- and bio-sensors derived from pristine MXenes or their nanocomposites. We first present the preparation strategies, surface modification, and performances of MXenes. Then, diverse chemo- and bio-sensors developed based on the MXenes are elaborated, including their unique properties, high sensitivity, and selectivity. Furthermore, we illustrate the related applications in the biomedical field and integrated biosensing platforms. In the end, the current challenges and future perspectives for MXene-based chemo- and bio-sensors are discussed.

Carbonized zein nanosheets with intrinsic enzyme-mimicking activities and high photothermal conversion efficiency for synergistic cancer therapy.

With the rapid development of biology and nanotechnology, designing nanomaterials with intrinsic enzyme-like activities has attracted huge attention in recent years. Herein, for the first time, we use zein as a new protein precursor to prepare N-rich carbonized zein nanosheets (C-Zein) via facile pyrolysis. Zein is an inert, biodegradable and sustainable natural biopolymer. After high-temperature carbonization, zein can be converted into highly catalytically active C-Zein, which can possess excellent peroxidase- and oxidase-like catalytic activities. Such intrinsic enzyme-like activities of C-Zein are closely related to its graphitization degree, the ratio of graphitic nitrogen and the formation of disordered graphene. Intriguingly, C-Zein also exhibits high photothermal conversion efficiency in the near-infrared (NIR) region. Coupling their unique photothermal and catalytic properties, the as-prepared C-Zein can act as a robust agent for synergistic photothermal-catalytic cancer treatment under the irradiation of NIR light. We expect that this work paves the way to use zein for designing efficient artificial enzymes and accelerate further growth in exploring its new biomedical and pharmaceutical applications.

The Role of Nanomaterials in Modulating the Structure and Function of Biomimetic Catalysts.

Nanomaterial-incorporated enzyme mimics have so far been examined in various cases, and their properties are governed by the properties of both catalysts and materials. This review summarizes recent efforts in understanding the role of inorganic nanomaterials for modulating biomimetic catalytic performance. Firstly, the importance of enzyme mimics, and the necessity for tuning their catalysis will be outlined. Based on structural characteristics, these catalysts are divided into two types: traditional artificial enzymes, and novel nanomaterial-based enzyme mimics. Secondly, the mechanisms on how nano-sized materials interact with these catalysts will be examined. Intriguingly, incorporating various nanomaterials into biomimetic catalysts may provide a convenient and highly efficient method for the modulation of activities as well as stabilities or introduce new and attractive features. Finally, the perspectives of the main challenges and future opportunities in the areas of nanomaterial-incorporated biomimetic catalysis will be discussed. In this regard, nanomaterials as a kind of promising scaffold for tuning catalysis will attract more and more attention and be practically applied in numerous fields.

Comparing efficacy of drug-coated balloon-only approach and stent approach in treating de novo coronary artery lesions: A meta-analysis of randomized controlled trials. A protocol for systematic review and meta-analysis.

BACKGROUND: Drug-coated balloons (DCB) have been a novel alternative therapeutic strategy in de novo coronary artery diseases. However, the clinical feasibility of the DCB-only approach in treating small vessel disease remains controversial, while study aimed to assess the efficacy and safety of the DCB-only approach versus stent approaches in treating large vessel disease is limited. METHODS: From February 2020 to May 2020, we will search Cochrane Library, PubMed, EMBASE, ScienceDirect, Scopus, Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure (CNKI), Wanfang Database, and Chongqing VIP Database for eligible trials comparing DCB with drug-eluting stents for treatment of de novo lesions in both small vessel disease and large vessel disease. The primary endpoint is major adverse cardiac events (MACE); the secondary endpoints include in-lesion late lumen loss, binary restenosis, myocardial infarction, target lesion revascularization (TLR), mortality and target vessel thrombosis. Meta-analysis will be conducted using Review Manager software (V.5.3). RESULTS: The results will be presented as risk ratios for dichotomous data, and weighted mean differences for continuous data. CONCLUSION: We will assess outcomes of the DCB-only approach in the treatment of de novo lesions compared with the stent approach. PROSPERO REGISTRATION NUMBER: CRD42020164484.

Wool Keratin Photolithography as an Eco-Friendly Route to Fabricate Protein Microarchitectures.

Herein, we present an eco-friendly route to construct protein microarchitectures by using wool keratin (WK) as a green biophotoresist. The photoactive WK was extracted from wool with a method of alkaline hydrolysis and reacted with 2-isocyanatoethyl methacrylate (IEM). The whole process can avoid the use of surfactant and does not cause apparent changes in the structure and function of WK. With the aid of direct-write photolithography, "photoresist-like" WK can be further used for fabricating well-defined and high-performance patterns at a low micron-scale (µm) without high temperature, complicated process, long time, and high production cost.

Hot-Electron-Activated Peroxidase-Mimicking Activity of Ultrathin Pd Nanozymes.

Light-activated nanozymes can provide a wealth of new opportunities for the chemical industry and biotechnology. However, present remote-controlled catalytic systems are still far from satisfactory. Herein, we present an interesting example of applying ultrathin Pd nanosheets (Pd NSs) as a light-controllable peroxidase mimic. Since most of Pd atoms are exposed on their surface, Pd NSs with a thickness of 1.1 nm possess high peroxidase-like activity. More importantly, under light excitation, such intrinsic activity can be further activated by a nearly 2.4- to 3.2-fold. Such a phenomenon can be ascribed to the unique optical property of ultrathin Pd NSs, which can efficiently capture photons to generate hot electrons via surface plasmon resonance effect and thus promote the in situ decomposition of H2O2 into reactive oxygen species radicals (O*). This enhanced catalysis can also be used for real-time and highly sensitive colorimetric detection of H2O2. We expect our work can provide valuable insights into the rational design of artificial nanozymes with controllable and efficient activity in biomedical diagnostics, drug delivery, and environmental chemistry.