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The slow kinetic process of the oxygen evolution reaction (OER) and poor electrochemical stability in acidic environments of electrocatalysts seriously restrict the efficiency of hydrogen production from proton exchange membrane water electrolyzers (PEMWEs). In recent years, developing corrosion-resistant and redox-active doped TiO2 with heterogeneous atoms has become an effective strategy to address this challenge. However, most of the reported studies only explore single-element doped TiO2-supported catalysts, and there are few reports comparing the doping effects of various elements at the experimental level, which is crucial for screening high-performance OER electrocatalysts. In this work, seven different metal elements M (M = V, Mn, Fe, Ni, Cu, Nb, W) are selected for doping anatase TiO2 with the same molar ratio (M/Ti) and combined with IrO2 nanoparticles to form M-doped TiO2-supported IrO2 (M–TiO2@IrO2) electrocatalysts. Electrochemical OER activity and stability results indicate that W–TiO2@IrO2 exhibits the best performance among all these catalysts in terms of comprehensively regulating the conductivity of TiO2 and the activity and stability of IrOx within the range of experimental design in this work, which originates from the appropriate energy band structure obtained through W doping, optimizing the intrinsic conductivity of the support and interfacial electronic structure between the metal oxide and support. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is a clinical syndrome characterized by a rapid decline in renal function, and is associated with a high risk of death. Many pathological changes happen in the process of AKI, including crucial alterations to oxidative stress levels. Numerous efforts have thus been made to develop effective medicines to scavenge excess reactive oxygen species (ROS). However, researchers have encountered several significant challenges, including unspecific biodistribution, high biotoxicity, and in vivo instability. To address these problems, engineered nanoparticles have been developed to target oxidative stress and treat AKI. This review thoroughly discusses the methods that empower nanodrugs to specifically target the glomerular filtration barrier and presents the latest achievements in engineering novel ROS‐scavenging nanodrugs in clustered sections. The analysis of each study's breakthroughs and imperfections visualizes the progress made in developing effective nanodrugs with specific biodistribution and oxidative stress‐targeting capabilities. This review fills the blank of a comprehensive outline over current progress in applying nanotechnology to treat AKI, providing potential insights for further research. [ABSTRACT FROM AUTHOR]

Current-sensing topology with multi resistors in series has limitations in improving the dynamic range of current acquisition, so a sensing topology with multi resistors in parallel is proposed. The overcurrent state of a parallel shunt circuit cannot be latched, resulting in protection hiccups. A dual threshold-detection circuit is designed to achieve protection state latching and self-recovery. The rectified mean circuit is applied for overcurrent magnitude detection and its validity is proved. But the delay and ripple of the output waveform of the rectified mean circuit may also cause protection hiccups. Combining Fourier series representation, Fourier transform and inverse transform, the time domain expressions of the output of the rectified mean circuit for three common waveforms are obtained. Furthermore, the estimation formulas for the residual ripple amplitude of the three waveforms are derived. In an experiment, the protection hiccup issue in parallel sensing topology was eliminated, while the time constants and hysteresis ratios of the protection circuits were properly set according to theoretical calculation results. With five parallel sensing resistors, the ratio of the maximum to minimum range of the single current channel reaches 1.28 × 10 4 , which is higher than counterparts with multiple series sensing resistors. The advantages of parallel sensing topology in improving dynamic range are confirmed. [ABSTRACT FROM AUTHOR]

PROteolysis TArgeting Chimeras (PROTACs) are an emerging class of promising therapeutic modalities that selectively degrade intracellular proteins of interest by hijacking the ubiquitin‐proteasome system. However, the lack of techniques to efficiently transport these degraders to targeted cells and consequently the potential toxicity of PROTACs limit their clinical applications. Here, a strategy of nanoengineered PROTACs, that is, Nano‐PROTACs, is reported, which improves the bioavailability of PROTACs and maximizes their capacity to therapeutically degrade intracellular oncogenic proteins for tumor therapy. The Nano‐PROTACs are developed by encapsulating PROTACs in glutathione (GSH)‐responsive poly(disulfide amide) polymeric (PDSA) nanoparticles and show that ARV@PDSA Nano‐PROTAC, nanoengineered BRD4 degrader ARV‐771, improves BRD4 protein degradation and decreases the downstream oncogene c‐Myc expression. Benefiting from the GSH‐scavenging ability to amply the c‐Myc‐related ferroptosis and cell cycle arrest, this ARV@PDSA Nano‐PROTACs strategy shows superior anti‐tumor efficacy with a low dose administration and good biocompatibility in vivo. The findings reveal the potential of the Nano‐PROTACs strategy to treat a broad range of diseases by dismantling associated pathogenic proteins. [ABSTRACT FROM AUTHOR]

Plateau pikas (Ochotona curzoniae) are often regarded as pests when their population densities exceed a certain threshold. Vegetation restoration measures are commonly used for the ecological control of pikas. Nevertheless, it is not known how effective these measures are, and if effective, which factors are responsible for the decline in pika densities. Four commonly used grassland restoration measures: exclosure [E], exclosure/fertilized [EF], exclosure/overseeding [EO], exclosure/fertilization/over‐seeding [EOF], were implemented in grasslands degraded by high densities of pikas, and the pika density (PD) and vegetation traits in each treatment plot were monitored for 4 consecutive years. Neither the PD nor the vegetation composition was affected by any of the vegetation restoration measures within the first year. From the second year onwards, all the vegetation restoration measures had a significant effect on the vegetation composition and structure, such as an increase in the height, cover, and biomass. All the vegetation restoration measures, except E, had a significant suppressive effect on pika densities as time progressed, with the combination EOF measure having the largest effect. The stepwise regression analysis indicated that the vegetation height is the main factor that determines the PD. Similarly, structural equation modelling showed that vegetation restoration measures reduce PD primarily by increasing vegetation height. This may be because the height of the vegetation is closely correlated to the predation risk of pikas. Our results highlight the importance of vegetation height in pika management, suggesting that the key to successful pika management is to find a sustainable grazing system, which is beneficial to the growth of the dominant graminoids and maintains a high plant diversity for the sustainability of grassland ecosystems. [ABSTRACT FROM AUTHOR]

Bacillus subtilis, as a biocontrol bacterium, possess a variety of biological functions and the capacity to control plant pathogens. Iturin A is a biosurfactant with broad‐spectrum antifungal activity produced by fermentation of B. subtilis. In this study, the dynamic parameters of solid‐state fermentation (SSF) and submerged fermentation (SMF) of Bacillus velezensis ND were compared, and a method for producing iturin A with a yield of 12.46 g/kg utilizing SSF was proposed. It has significant advantages over SMF and has the highest yield of all previously reported studies. B. velezensis ND also contains protease activity, cellulase activity, iron‐carrying activity, the ability to synthesis 3‐indoleacetic acid (IAA), fixation nitrogen, and degrade phosphorus. In cotton pot experiments, it can effectively increase cotton growth and minimize Verticillium wilt. This strain's superior fermentation efficiency, biological function, and biocontrol ability are sufficient to demonstrate its promise for the development and use of biocontrol agents. [ABSTRACT FROM AUTHOR]

In recent years, there have been significant innovations in the development of nanoparticle‐based vaccines and vaccine delivery systems. For the purposes of both design and evaluation, these nanovaccines are imaged using the wealth of understanding established around medical imaging of nanomaterials. An important insight to the advancement of the field of nanovaccines can be given by an analysis of the design rationale of an imaging platform, as well as the significance of the information provided by imaging. Nanovaccine imaging strategies can be categorized by the imaging modality leveraged, but it is also worth understanding the superiority or convenience of a given modality over others in a given context of a particular nanovaccine. The most important imaging modalities in this endeavor are optical imaging including near‐infrared fluorescence imaging (NIRF), emission tomography methods such as positron emission tomography (PET) and single photon emission computed tomography (SPECT) with or without computed tomography (CT) or magnetic resonance (MR), the emerging magnetic particle imaging (MPI), and finally, multimodal applications of imaging which include molecular imaging with magnetic resonance imaging (MRI) and photoacoustic (PA) imaging. One finds that each of these modalities has strengths and weaknesses, but optical and PET imaging tend, in this context, to be currently the most accessible, convenient, and informative modalities. Nevertheless, an important principle is that there is not a one‐size‐fits‐all solution, and that the specific nanovaccine in question must be compatible with a particular imaging modality. This article is categorized under:Nanotechnology Approaches to Biology > Nanoscale Systems in BiologyTherapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic DiseaseTherapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease [ABSTRACT FROM AUTHOR]

In the field of nanomedicine, there is a tendency of matching designed nanomaterials with a suitable type of orthotopic cancer model, not just a casual subcutaneous one. Under this condition, knowing the specific features of the chosen cancer model is the priority, then introducing a proper therapy strategy using designed nanomaterials. Here, the Fenton chemistry is combined with zinc peroxide nanoparticles in the treatment of orthotopic liver cancer which has a "chemical factory" including that liver is the main place for iron storage, metabolism, and also the main metabolic sites for the majority of ingested substances, guaranteeing customized and enhanced chemodynamic therapy and normal liver cells protection as well. The good results in vitro and in vivo can set an inspiring example for exploring and utilizing suitable nanomaterials in corresponding cancer models, ensuring well‐fitness of nanomaterials for disease and satisfactory therapeutic effect. [ABSTRACT FROM AUTHOR]

The great success achieved by the two highly-effective messenger RNA (mRNA) vaccines during the COVID-19 pandemic highlights the great potential of mRNA technology. Through the evolution of mRNA technology, chemistry has played an important role from mRNA modification to the synthesis of mRNA delivery platforms, which allows various applications of mRNA to be achieved both in vitro and in vivo. In this tutorial review, we provide a summary and discussion on the significant progress of emerging mRNA technologies, as well as the underlying chemical designs and principles. Various nanoparticle (NP)-based delivery strategies including protein-mRNA complex, lipid-based carriers, polymer-based carriers, and hybrid carriers for the efficient delivery of mRNA molecules are presented. Furthermore, typical mRNA delivery platforms for various biomedical applications (e.g., functional protein expression, vaccines, cancer immunotherapy, and genome editing) are highlighted. Finally, our insights into the challenges and future development towards clinical translation of these mRNA technologies are provided. [ABSTRACT FROM AUTHOR]

The local electron density of an atom is one key factor that determines its chemical properties. Regulating electron density can promote the atom's reactivity and so reduce the reaction activation energy, which is highly desired in many chemical applications. Herein, we report an intra‐crystalline electron lever strategy, which can regulate the electron density of reaction centre atoms via manipulating ambient lattice states, for Fenton activity improvement. Typically, with the assistance of ultrasound, the Mn4+−O−Fe3+ bond in BiFe0.97Mn0.03O3 perovskite nanocrystals can drive valence electrons and free electrons to accumulate on Fe atoms by a polarization electric field originated from the designed lattice strain. The increase of electron density significantly improves the catalytic activity of Fe, decreasing the activation energy of BiFe0.97Mn0.03O3‐mediated Fenton reaction by 52.55 %, and increasing the.OH yield by 9.21‐fold. This study provides a new way to understand the sono‐Fenton chemistry, and the increased.OH production enables a highly effective chemodynamic therapy. [ABSTRACT FROM AUTHOR]

Ultrasound (US)‐mediated sonodynamic therapy (SDT) has emerged as a superior modality for cancer treatment owing to the non‐invasiveness and high tissue‐penetrating depth. However, developing biocompatible nanomaterial‐based sonosensitizers with efficient SDT capability remains challenging. Here, we employed a liquid‐phase exfoliation strategy to obtain a new type of two‐dimensional (2D) stanene‐based nanosheets (SnNSs) with a band gap of 2.3 eV, which is narrower than those of the most extensively studied nano‐sonosensitizers, allowing a more efficient US‐triggered separation of electron (e−)‐hole (h+) pairs for reactive oxygen species (ROS) generation. In addition, we discovered that such SnNSs could also serve as robust near‐infrared (NIR)‐mediated photothermal therapy (PTT) agents owing to their efficient photothermal conversion, and serve as nanocarriers for anticancer drug delivery owing to the inherent 2D layered structure. This study not only presents general nanoplatforms for SDT‐enhanced combination cancer therapy, but also highlights the utility of 2D SnNSs to the field of nanomedicine. [ABSTRACT FROM AUTHOR]

Pnictogens (the non-metal phosphorus, metalloids arsenic and antimony, and metal bismuth) possess diverse chemical characteristics that support the formation of extended molecular structures. As witnessed by the centuries-old (and ongoing) clinical utilities, pnictogen-based compounds have secured their places in history as "magic bullet" therapeutic drugs in medicinal contexts. Moreover, with the development of recent metalloproteomics and bio-coordination chemistry, the pnictogen-based drugs functionally binding to proteins/enzymes in biological systems have been underlaid for "drug repurposing" with promising opportunities. Furthermore, advances in the modern materials science and nonotechnology have stimulated a revolution in other newly discovered forms of pnictogens—phosphorene, arsenene, antimonene, and bismuthine (layered pnictogens). Based on their favorable optoelectronic properties, layered pnictogens have shown dramatic superiority as emerging photonic nanomedicines for the treatment of various diseases. This tutorial review outlines the history and mechanism of action of ancient pnictogen-based drugs (e.g., arsenical compounds in traditional Chinese medicine) and their repurposing into modern therapeutics. Then, the revolutionary use of emerging layered pnictogens as photonic nanomedicines, alongside assessments of their in vivo biosafety, is discussed. Finally, the challenges to further development of pnictogens are set forth and insights for further exploration of their appealing properties are offered. This tutorial review may also provide some deep insights into the fields of integrated traditional Chinese and Western medicines from the perspective of materials science and nanotechnology. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDCs) are increasingly being used for chemical sensing, biosensing, and tumor therapy on account of their diversity, biocompatibility, multifunctionality, adjustable bandgap, and excellent photoelectric characteristics. This review mainly discusses the effect of the elemental composition and structure of TMDCs on the performance of electrochemical, biofluorescence, and colorimetric biosensors. The applications of TMDCs in tumor therapies are reviewed here. Furthermore, the current challenges and future directions for developing TMDC‐based theranostics are summarized. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is a lifelong metabolic disease that requires frequent subcutaneous injections of insulin. However, this method of administration can be associated with patient discomfort and local tissue infection. Oral delivery of insulin has been pursued as a more convenient method for diabetes treatment, given its likely superior patient compliance and convenience as well as cost‐effectiveness. However, various biological barriers hinder the clinical translation of oral insulin. The rapid development of nanotechnology over the last decade offers great promise in improving the bioavailability of oral insulin. This Minireview provides an overview of biological barriers to oral insulin delivery, summarizes significant technological advances, and outlines future perspectives in oral insulin formulations as well as their hypoglycaemic effects. [ABSTRACT FROM AUTHOR]

Diabetes mellitus ist eine lebenslange Stoffwechselerkrankung, die häufige subkutane Insulininjektionen erfordert. Diese Verabreichungsmethode kann jedoch mit Beschwerden des Patienten und einer lokalen Gewebeinfektion verbunden sein. Die orale Verabreichung von Insulin wird aufgrund der wahrscheinlich überlegenen Patientencompliance und ‐bequemlichkeit sowie der Kosteneffizienz als bequemere Methode zur Behandlung von Diabetes verfolgt. Verschiedene biologische Barrieren behindern jedoch die klinische Translation von oralem Insulin. Die rasante Entwicklung der Nanotechnologie im letzten Jahrzehnt bietet vielversprechende Möglichkeiten zur Verbesserung der Bioverfügbarkeit von oralem Insulin. Dieser Kurzaufsatz gibt einen Überblick über biologische Barrieren für die orale Insulinabgabe, fasst wichtige technische Fortschritte zusammen und skizziert zukünftige Perspektiven in oralen Insulinformulierungen sowie deren hypoglykämische Wirkungen. [ABSTRACT FROM AUTHOR]

Excess electrons play important roles for the construction of superficial active sites on nanocatalysts. However, providing excess electrons to nanocatalysts in vivo is still a challenge, which limits the applications of nanocatalysts in biomedicine. Herein, auger electrons (AEs) emitted from radionuclide 125 (125I) are used in situ to construct active sites in a nanocatalyst (TiO2) and the application of this method is further extended to cancer catalytic internal radiotherapy (CIRT). The obtained 125I‐TiO2 nanoparticles first construct superficial Ti3+ active sites via the reaction between Ti4+ and AEs. Then Ti3+ stretches and weakens the OH bond of the absorbed H2O, thus enhancing the radiolysis of H2O molecules and generating hydroxyl radicals (•OH). All in vitro and in vivo results demonstrate a good CIRT performance. These findings will broaden the application of radionuclides and introduce new perspectives to nanomedicine. [ABSTRACT FROM AUTHOR]