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Innovative fluorescence materials combining the special reagent stimuli response have considerable potential to provide a convenient and highly secure communication strategy for encoding messages. With the unique decryption method, encrypted information that is previously unidentifiable can now be accurately parsed without the risk of interception or decipherment. Herein, white‐emitting light semiconducting polymer dots for advanced secret communication are developed, along with a machine learning‐based encryption‐decryption strategy. The encrypted data are readily hidden by the fluorescent polymer‐stimulus system, which can be identified by fluorescence imaging equipment and only be decrypted via the special linear discriminant analysis route pre‐transferred to the recipient. The results presented here suggest that chemical‐stimulated fluorescence information storage and the unique decoding strategy can be developed as prospective methods for advanced data communication and security protection. [ABSTRACT FROM AUTHOR]

The fluorescence quenching spectra of neuroglobin by cesium ion, iodide and acrylamide, synchronous fluorescence spectra, and 8-anilino-1-naphthalene-sulfonic acid binding property were investigated. The intrinsic fluorescence of neuroglobin cannot be effectively quenched by cesium ion, with a Stern–Volmer constant of 0.23 ± 0.01. However, it can be significantly quenched by iodide and acrylamide with Stern–Volmer constants of 1.30 ± 0.04 and 4.56 ± 0.10, respectively. The results of synchronous fluorescence spectra indicate that tryptophan residues are distributed on both the surface and interior of neuroglobin molecule, but most of them are buried in the hydrophobic interior. The neuroglobin molecule has different conformational states in various pH solutions. [ABSTRACT FROM PUBLISHER]

Aβ oligomers have been widely accepted as significant biomarkers for Alzheimer's disease (AD) detection, monitoring, and therapy since they are highly correlated with AD development. In this work, an electrochemical array-based sensing platform was successfully built using a group of functionalized graphene with different physicochemical features. Since the electro-insulated Aβ peptide species severely interfered with the electron transport on the electrode surface, the presence of Aβ led to a significant change in the electrochemical impedance signal. The resulting variety of the impedance was then classified and processed by linear discriminant analysis. The constructed sensing platform can discriminate different Aβ forms, the mixture of various Aβ forms, and different ratios of Aβ42 to Aβ40 with 100% accuracy by only the combination of dual probes. Furthermore, it also exhibited excellent performance for screening Aβ inhibitors and metal chelators. The strategy utilizes the infinitesimal general discrepancy instead of specific biomarker recognition, exhibiting the advantage of no requirement to know the exact information about the specific ligand and receptor in advance, which is promising to be widened for the other biosensing detection fields. • A facile functionalized graphene-based electrochemical array sensor was successfully constructed. • The prepared sensing platform could discriminate different Aβ forms, the mixture of various Aβ forms, and different ratios of Aβ42 to Aβ40 in buffered solutions as well as in complex body fluid environments. • 100% identification through the combination of dual probes was achieved, indicating the super diagnostic capacity of the sensor array. • The strategy utilizes the infinitesimal general discrepancy instead of specific biomarker recognition. [ABSTRACT FROM AUTHOR]

A novel ratiometric electrochemical nanosensing platform was developed based on graphene and mesoporous hybrid nanomaterials for detection of the mutated apolipoprotein E gene associated with Alzheimer's disease. The introduction of ratiometric assay could cancel out some systematic errors and significantly improved the sensing performance, such as reproducibility, reliability and accuracy. [ABSTRACT FROM AUTHOR]

Graphene has emerged as a novel green broad-spectrum antibacterial material, with little bacterial resistance and tolerable cytotoxic effect on mammalian cells. It exerts its antibacterial action via physical damages such as direct contact of its sharp edges with bacterial membranes and destructive extraction of lipid molecules. These damages also include wrapping and photothermal ablation mechanisms. Alternatively, chemical damage of bacteria is caused by oxidative stress with the generation of reactive oxygen species and charge transfer. Furthermore, graphene has been used as a support to disperse and stabilize various nanomaterials, such as metals, metal oxides, and polymers, with high antibacterial efficiency due to the synergistic effect. In addition, graphene-based antibiotic drug delivery platforms have been constructed. Due to the superior antibacterial properties and good biocompatibility, graphene-based nanocomposites have a wide range of applications, such as antibacterial packaging, wound dressing, and water disinfection. In this review, we highlight the antibacterial mechanism of graphene and summarize recent advances related to the antibacterial activity of graphene-based materials. Many of the recent application examples are further discussed. We hope that this review provides valuable insight, stimulates broader concerns, and spurs further developments in this promising field. [ABSTRACT FROM AUTHOR]

Extracellular DNA (eDNA) is an essential structural component during biofilm formation, including initial bacterial adhesion, subsequent development, and final maturation. Herein, the construction of a DNase-mimetic artificial enzyme (DMAE) for anti-biofilm applications is described. By confining passivated gold nanoparticles with multiple cerium(IV) complexes on the surface of colloidal magnetic Fe3O4 /SiO2 core/shell particles, a robust and recoverable artificial enzyme with DNase-like activity was obtained, which exhibited high cleavage ability towards both model substrates and eDNA. Compared to the high environmental sensitivity of natural DNase in anti-biofilm applications, DMAE exhibited a much better operational stability and easier recoverability. When DMAE was coated on substratum surfaces, biofilm formation was inhibited for prolonged periods of time, and the DMAE excelled in the dispersion of established biofilms of various ages. Finally, the presence of DMAE remarkably potentiated the efficiency of traditional antibiotics to kill biofilm-encased bacteria and eradiate biofilms. [ABSTRACT FROM AUTHOR]

Extracellular DNA (eDNA) is an essential structural component during biofilm formation, including initial bacterial adhesion, subsequent development, and final maturation. Herein, the construction of a DNase-mimetic artificial enzyme (DMAE) for anti-biofilm applications is described. By confining passivated gold nanoparticles with multiple cerium(IV) complexes on the surface of colloidal magnetic Fe3O4 /SiO2 core/shell particles, a robust and recoverable artificial enzyme with DNase-like activity was obtained, which exhibited high cleavage ability towards both model substrates and eDNA. Compared to the high environmental sensitivity of natural DNase in anti-biofilm applications, DMAE exhibited a much better operational stability and easier recoverability. When DMAE was coated on substratum surfaces, biofilm formation was inhibited for prolonged periods of time, and the DMAE excelled in the dispersion of established biofilms of various ages. Finally, the presence of DMAE remarkably potentiated the efficiency of traditional antibiotics to kill biofilm-encased bacteria and eradiate biofilms. [ABSTRACT FROM AUTHOR]

The biofilm resistance of microorganisms has severe economic and environmental implications, especially the contamination of facilities associated with human life, including medical implants, air-conditioning systems, water supply systems, and food-processing equipment, resulting in the prevalence of infectious diseases. Once bacteria form biofilms, their antibiotic resistance can increase by 10–1,000-fold, posing a great challenge to the treatment of related diseases. In order to overcome the contamination of bacterial biofilm, destroying the biofilm's matrix so as to solve the penetration depth dilemma of antibacterial agents is the most effective way. Here, a magnetically controlled multifunctional micromotor was developed by using H 2 O 2 as the fuel and MnO 2 as the catalyst to treat bacterial biofilm infection. In the presence of H 2 O 2 , the as-prepared motors could be self-propelled by the generated oxygen microbubbles. Thereby, the remotely controlled motors could drill into the EPS of biofilm and disrupt them completely with the help of bubbles. Finally, the generated highly toxic •OH could efficiently kill the unprotected bacteria. This strategy combined the mechanical damage, highly toxic •OH, and precise magnetic guidance in one system, which could effectively eliminate biologically infectious fouling in microchannels within 10 min, possessing a wide range of practical application prospects especially in large scale and complex infection sites. [Display omitted] • Mechanical damage, highly toxic •OH, and precise magnetic guidance were integrated in one antimicrobial system. • H 2 O 2 was used as the fuel to trigger the high-speed movement of motor and serve as the source of high toxic •OH. • Enhanced antibacterial activities were obtained even for the treatment of drug-resistant bacteria MRSA. • The micro-nano hybrid multifunctional motors developed here are precisely controlled and deeply penetrated. • Motors have strong destructive ability for the treatment of large-scale biofilm EPS even at complex infection sites. [ABSTRACT FROM AUTHOR]

A powerful strategy for long-term and diffusional-resistance-minimized whole-cell biocatalysis in biphasic systems is reported where individually encapsulated bacteria are employed as robust and recyclable Pickering interfacial biocatalysts. By individually immobilizing bacterial cells and optimizing the hydrophobic/hydrophilic balance of the encapsulating magnetic mineral shells, the encased bacteria became interfacially active and locate at the Pickering emulsion interfaces, leading to dramatically enhanced bioconversion performances by minimizing internal and external diffusional resistances. Moreover, in situ product separation and biocatalyst recovery was readily achieved using a remote magnetic field. Importantly, the mineral shell effectively protected the entire cell from long-term organic-solvent stress, as shown by the reusability of the biocatalysts for up to 30 cycles, while retaining high stereoselective catalytic activities, cell viabilities, and proliferative abilities. [ABSTRACT FROM AUTHOR]

A powerful strategy for long-term and diffusional-resistance-minimized whole-cell biocatalysis in biphasic systems is reported where individually encapsulated bacteria are employed as robust and recyclable Pickering interfacial biocatalysts. By individually immobilizing bacterial cells and optimizing the hydrophobic/hydrophilic balance of the encapsulating magnetic mineral shells, the encased bacteria became interfacially active and locate at the Pickering emulsion interfaces, leading to dramatically enhanced bioconversion performances by minimizing internal and external diffusional resistances. Moreover, in situ product separation and biocatalyst recovery was readily achieved using a remote magnetic field. Importantly, the mineral shell effectively protected the entire cell from long-term organic-solvent stress, as shown by the reusability of the biocatalysts for up to 30 cycles, while retaining high stereoselective catalytic activities, cell viabilities, and proliferative abilities. [ABSTRACT FROM AUTHOR]

Herein, a new strategy has been developed through combining a microwave-assisted technique with hydrothermal treatment to reduce graphene waste and improve production yield of graphene quantum dots (GQDs) prepared by top-down methods. By using fluorinated graphene oxide (FGO) as a raw material, fluorinated GQDs and nonfluorinated GQDs can be synthesized. Additionally, in the fluorinated GQDs, the protective shell supplied by fluorine improves the pH stability of photoluminescence and the strong electron-withdrawing group, F, reduces the π- electron density of the aromatic structure; thus inhibiting reactivity toward singlet oxygen produced during irradiation and improving the photostability. Therefore, the as-prepared fluorinated GQDs with excellent photo- and pH stability are suitable for long-term cellular imaging. [ABSTRACT FROM AUTHOR]

Cyclin A2 is a promising cancer prognostic indicator, but its intracellular in situ imaging is still a challenging task. This work designs an “off–on” fluorescent probe, which can fluorescently detect intracellular cyclin A2 and distinguish cancer cells. In addition, this work sheds light on the development of future protein biosensors. [ABSTRACT FROM AUTHOR]

The expression, purification and spectra characterization of recombinant human neuroglobin (NGB) are reported. The pET3a plasmid with the gene of NGB was transformed to E. coli BL21 (DE3) plys cells and expressed in TB culture medium. The results indicated that the expression amount of NGB is about 10 percent of the total protein in cells. The NGB protein was purified by ammonium sulfate precipitation, DEAE-Sepharose anion exchange column, Hiload 16/60 superdex 75 size exclusion chromatography and a Hip rep 16/10 Q FF anion exchange column, and a red soluble protein was obtained which showed a single band in electrophoresis. Electrospray ionization mass spectrometry (ESI-MS) showed that its molecular weight is 16930.0 Da. U V-spectra indicated that the reduced NGB has a strong absorption peak at 425 nm, and two weak peaks at 531 and 559 nm, which can be assigned to γ, β and a bands of porphyrin, respectively, and the oxidized NGB has a strong absorption peak at 413 nm which corresponds to the transition of it electrons in the porphyrin ring. The fluorescence maximal excitation wavelength is at 281 nm and its maximal emission wavelength is at 338 nm. CD spectra indicated that its secondary structure is a typical a helix, and has a positive peak at 410 nm induced by heme. The NGB protein is stable when the pH is higher than 4. [ABSTRACT FROM AUTHOR]

• The persistent luminescent material exhibits robust optical performance in the healthcare field. • Various testing and therapeutic techniques have been developed by integrating the unique long afterglow properties. • Increased efforts have been made to improve the brightness and durability of the new material. • PLM-based techniques are promising to solve more public health problems in various scenarios. With the advancement of human civilization and the growing diversity and multipolarity of the international community, there is a mounting emphasis on addressing public health and safety concerns. In order to respond to public safety incidents, the development of in-situ, timely, and sensitive detection methods has become the key. The pursuit of a high quality of life has revolutionized the investigation and evaluation of epidemics, tumors, and endemic diseases, necessitating tracing based on unique genetic sequences or antigenic properties of pathogenic microorganisms, tumor markers, and bioactive molecules. Additionally, the prevalence of food safety incidents has fostered societal expectations for continuous assurance through the detection of pesticide and bio-enzyme residues, environmental and industrial pollutants, as well as monitoring hazardous substances in food production. Due to its unique optical phenomenon and persistent afterglow emissions following stimulation cessation, persistent luminescent materials (PLMs) have garnered increased research attention across various sectors. The ability to quench in situ excitation and retain energy for extended durations has positioned them as an appealing system for implementation in luminescence imaging and sensing applications pertaining to public health and safety. This review aims to provide a comprehensive overview of groundbreaking work conducted over the past five years in the field of PLMs in relation to public health. We first highlight the luminescence principles of PLMs. In the following parts, we provide comprehensive coverage of the latest advancements and trends in the application of PLMs as biosensors in clinical examination and food contaminant analysis. Moreover, we emphasize their advantages in the application of antimicrobial treatment and light-guided tumor treatment. Finally, we discuss the future research directions and challenges in developing of PLMs for public health. [ABSTRACT FROM AUTHOR]

The use of Formic acid as an alternative to fossil fuels is promising, both from economical and ecological standpoints, and has received great of attention owing to its inherently superiority in recent decades. Nevertheless, efficient and low-cost solid catalyst for formic acid dehydrogenation at room temperature still constitutes a biggish challenge. Moreover, comparing to increase the catalytic performance of catalysts, very little attention payed to the kinetic mechanism of dehydrogenation reaction because of the lack of effective characterization artifice. Here, the as-prepared Ni@Pd nanoparticles by a sequential reduction process can be useful catalyst for formic acid decomposition at room temperature without a promoter. Thanks to the effective catalyst and isotope distribution technique, preliminary mechanistic results firstly reveal that hydrogen is obtained via a H-atom recombination on isolated sites after the proton exchange randomly between activated H and solvent. • The catalyst shows the enhanced formic acid dehydrogenation performance (645 h−1). • The Ni-core helps to increase the activity and CO resistance of Pd a lot. • Compare to pure Pd NCs, the cost of catalyst is greatly reduced. • Activated H exchange with water was firstly revealed by isotope substitution design. [ABSTRACT FROM AUTHOR]

The experimental study on heat transfer and pressure drop for R417A flow boiling in horizontal smooth and internally grooved tubes was conducted. Based on the experimental results, heat transfer and pressure drop performance for R417A in different tubes were compared, and the influences of vapor quality and mass flux on heat transfer enhancement and pressure drop performance were analyzed and discussed. The result indicates: enhancement factors of R417A in Tube II and Tube III focus on a range of 1.26–2.0 and 1.5–2.8 respectively, and enhancement factors vary with vapor qualities and mass fluxes. The total pressure drops for R417A in Tube II and Tube III are 1.8–2.6 times and 1.67–2.3 times of R417A in smooth tube respectively. Both enhancement factor and penalty factor increase with increasing mass flux, while enhancement parameters show different situations in different internally grooved tubes. Compared with Tube II, Tube III possesses a better heat transfer enhancement efficiency. [ABSTRACT FROM AUTHOR]

Pathogens and contaminants in food and the environment present significant challenges to human health, necessitating highly sensitive and specific diagnostic methods. Traditional approaches often struggle to meet these requirements. However, the emergence of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) system has revolutionized nucleic acid diagnostics. The present review provides a comprehensive overview of the biological sensing technology based on the CRISPR/Cas system and its potential applications in public health-related analysis. Additionally, it explores the enzymatic cleavage capabilities mediated by Cas proteins, highlighting the promising prospects of CRISPR technology in addressing bioanalysis challenges. We discuss commonly used CRISPR-Cas proteins and elaborate on their application in detecting foodborne bacteria, viruses, toxins, other chemical pollution, and drug-resistant bacteria. Furthermore, we highlight the advantages of CRISPR-based sensors in the field of public health-related analysis and propose that integrating CRISPR-Cas biosensing technology with other technologies could facilitate the development of more diverse detection platforms, thereby indicating promising prospects in this field. The present study provides an overview of the potential applications of CRISPR technology in the field of public health, encompassing foodborne bacteria, viruses, toxins, other chemical pollutants, and drug-resistant bacteria. [Display omitted] • The present study provides a comprehensive review on the utilization of the CRISPR system in public health surveillance. • Applications of CRISPR technology in the detection of foodborne bacteria, viruses, environmental toxins, pollutants, and drug-resistant bacteria were employed. • The benefits, drawbacks and improvement ideas of these sensors were elaborated. [ABSTRACT FROM AUTHOR]

Sensitive and accurate detection of DNA methyltransferase (MTase) is conducive to the understanding of the fundamental biological processes related to DNA methylation, clinical disease diagnosis, and drug discovery. Herein, a new fluorescence transducer based on Förster resonance energy transfer (FRET) between the donor upconversion nanoparticles (UCNPs) and the efficient acceptor gold nanorods (AuNRs) for MTase activity analysis and its inhibitor screening is presented. A double-strand DNA linker between UCNPs and AuNRs could be digested by restriction endonuclease HhaI, preventing the FRET process and recovering the upconversion luminescence (UCL) intensity. With the treatment of MTase, the cutting site was disturbed by the methylation of cytosine, blocking the enzyme digestion. The transducer presented here showed an excellent analytical performance toward MTase M.HhaI in the concentration range 0.08~24 U mL−1 with a detection limit of 0.057 U mL−1 calculated according to the UCL intensity changes at 656 nm excited by 980 nm CW laser, which is superior to most of the reported methods. Furthermore, the as-fabricated transducer also demonstrated high testing and screening capability toward enzyme inhibitors' evaluation. The method takes the advantage of low background fluorescence of UCNPs to improve the accuracy of the measurement, which can be developed as a general strategy for the analysis of various disease-related methyltransferase activity and their corresponding inhibitors, offering a promising strategy for high-performance diagnosis, high-efficient drug exploitation, and treatment effectiveness evaluation. [ABSTRACT FROM AUTHOR]

We summarized the recent advances of functional MOFs- and COFs-based efficient sensing platforms developed for the measurement of foodborne contaminants. [Display omitted] • The harms of food-borne contaminants to human society are reviewed. • Brief introduction of metal–organic frameworks (MOFs) and covalent organic frameworks was concluded. • Recent advances for the detection foodborne organic contaminants based on MOFs and COFs were summarized. • Future challenges in the actual application and insights into the future directions in this promising field was discussed. Foodborne organic contaminants against health, mainly including antibiotics, pesticides, mycotoxins, foodborne bacteria, etc., have been considered one of the global public health problems. The early detection of these organic contaminants before consumption can significantly reduce the risk of acute or chronic food poisoning. Therefore, it's of great significance to develop effective sensing strategies for convenient, rapid, sensitive, and selective food quality monitoring. Metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), as highly promising porous materials with multifunctionality, exhibit broad prospects in the field of chemical or biological sensing. They possess great potential to meet the requirements for detecting numerous analytes. Here, we summarized the recent advances of functional MOFs- and COFs-based efficient sensing platforms developed for the measurement of foodborne contaminants. In addition, a brief discussion of the future challenges in the practical application of these platforms and insights into the future directions in this promising field was also included. [ABSTRACT FROM AUTHOR]

Considering the intrinsic complexity of cancer, the emergence of multifunctional nanocarriers provides more possibilities for cancer therapy. Herein, a novel multifunctional nanocarrier (g-CNQDs–PEG–RGD) is successfully developed by covalently grafting graphitic-C3N4 quantum dots (g-CNQDs) with arginine–glycine–aspartic acid (RGD) via diamine-terminated oligomeric polyethylene glycol (PEG). The functionalization of g-CNQDs with PEG and RGD imparts the nanocomposite with low cytotoxicity, excellent physiological stability and specific targeting ability toward cancer cells with the αvβ3 receptor. The widely used fluorescent antineoplastic anthracycline drug doxorubicin (DOX) is non-covalently loaded onto g-CNQDs–PEG–RGD. It is advantageous that the g-CNQDs–PEG–RGD–DOX nano-assembly exhibits enhanced cellular uptake by HepG2 cells, which overexpress integrin αvβ3 receptors. Thus, the enhanced targeting specificity and intracellular acid condition-triggered drug release promise excellent therapeutic effects. Meanwhile, the inherent stable fluorescence of g-CNQDs–PEG–RGD and DOX enables real-time monitoring of cellular uptake of the g-CNQDs–PEG–RGD–DOX nano-assembly, consequent release of DOX and the fate of the carrier. These findings demonstrate that g-CNQDs–PEG–RGD–DOX will be promising for high treatment efficacy with minimal side effects in future therapy. [ABSTRACT FROM AUTHOR]

Water pollution caused by harmful heavy metal ions (HMIs) can significantly impact aquatic ecosystems and pose a high risk to human health. In this work, equipped with ultra-high fluorescence brightness, efficient energy transfer, and environmentally friendly performance, polymer dots (Pdots) were employed to construct a pattern recognition fluorescent HMIs detection platform. A single-channel unary Pdots differential sensing array was first developed to identify multiple HMIs with 100% classification accuracy. Then an "all-in-one" multiple Förster resonance energy transfer (FRET) Pdots differential sensing platform was constructed to discriminate HMIs in the artificial polluted water samples and actual water samples, exhibiting high classification accuracy in distinguishing HMIs. The proposed strategy leverages the compounded cumulative differential variation of diverse sensing channels for analytes, which is anticipated to find extensive applications in other fields for detection purposes. • The ultra-brightness and high stability of Pdots sensors render them highly promising for efficiently detecting heavy metal ions. • The preparation and detection process of Pdots-based sensors were facile and user-friendly. • The implementation of an "all-in-one" strategy simplified the process by consolidating multiple assays into a single one. • The streamlined detection process can effectively mitigate analytical errors arising from multiple experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • A comprehensive overview of smart singlet oxygen carriers for enhanced cancer photodynamic therapy is presented. • A summary of the traditional preparative strategies for the design and fabrication of singlet oxygen carriers is discussed. • A demonstration of the photodynamic therapy performance improved by naphthalenes, anthracenes, and pyridines-derived small molecules or polymers is systematically discussed in detail. • A brief outlook on the future research and development of singlet oxygen carriers is also articulated. Hypoxia is a significant feature of the tumor, which has been proved to be the major challenge in translating photodynamic therapy (PDT) into clinical applications. To solve this issue, singlet oxygen carriers have been used to relieve tumor hypoxia and accordingly improve the therapeutic effect of PDT. Herein, a systematic summary of recent progress in the design and preparation of singlet oxygen carriers to overcome the hypoxia issue and realize the enhanced PDT is presented. For discussing purpose, the typical molecular backbone applied for the design and fabrication of an intelligent singlet oxygen carrier is firstly discussed, with an emphasis on the mechanism interpretation of the reversible trap and release of singlet oxygen. Furthermore, the enhanced PDT realized by innovative singlet oxygen carriers is systematically discussed in detail, including therapeutic platforms based on naphthalenes, anthracenes, and pyridines-derived small molecules or polymers. Finally, some critical points for singlet oxygen carrier design and an outlook for the future research and development of this promising field are provided. We sincerely anticipate the information presented in this review to provide insightful design guidelines for the further development of precise and efficient antitumor application systems based on the singlet oxygen carrier. [ABSTRACT FROM AUTHOR]

Abstract: The enzyme 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase (HDR) is a terminal-acting enzyme in the plastid MEP pathway, which produce isoprenoid precursors. The full-length cDNA of HDR, designated SmHDR1 (Genbank Accession No. JX516088), was isolated for the first time from Salvia miltiorrhiza Bge. f. alba. SmHDR1 contains a 1389-bp open reading frame encoding 463 amino acids. The deduced SmHDR1 protein, which shows high identity to HDRs of other plant species, is predicted to possess a chloroplast transit peptide at the N-terminus and four conserved cysteine residues. Transcription pattern analysis revealed that SmHDR1 has high levels of transcription in leaves and low levels of transcription in roots and stems. The expression of SmHDR1 was induced by 0.1 mM methyl-jasmonate (MeJA) and salicylic acid (SA), but not by 0.1 mM abscisic acid (ABA), in the hairy roots of S. miltiorrhiza Bge. f. alba. Complementation of SmHDR1 in the Escherichia coli HDR mutant MG1655 ara < > ispH demonstrated the function of this enzyme. A functional color assay in E. coli showed that SmHDR1 accelerates the biosynthesis of β-carotene, indicating that SmHDR1 encodes a functional protein. Overexpression of SmHDR1 enhanced the production of tanshinones in cultured hairy roots of S. miltiorrhiza Bge. f. alba. These results indicate that SmHDR1 is a novel and important enzyme involved in the biosynthesis of diterpenoid tanshinones in S. miltiorrhiza Bge. f. alba. [Copyright &y& Elsevier]

Neuroglobin (NGB) is a newly discovered member of the hemoglobin superfamily that is primarily expressed in the brain of humans and other vertebrates. The effects of protein concentration, solvent, pH and temperature on the secondary structure of NGB were investigated by employing far UV circular dichroism (CD) spectroscopy. The results show that NGB exists mainly in α-helix form when its concentration is less than 10 μmol/L. However, its α-helix content decreases with the increase of concentration in the range of 10–40 μmol/L and remains unchanged when the concentration is higher than 40 μmol/L, which suggest that NGBs form intermolecular disulfide bond and aggregate in higher concentration. The α-helix content of NGB in methanol and ethanol is a little higher than that in water, indicating a higher stability of NGB in these solvents. NGB loses its α-helical secondary structure in either acidic or alkaline solution to some extent. Although increased temperature destabilizes the α-helices of NGB, over 16% of α-helices can be kept at 110°C. Therefore, NGB is a protein with hyperthermal stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional nanoplatform (g-CPFD) based on g-C 3 N 4 quantum dots is synthesized. • The g-CPFD achieves chemo-photodynamic combination therapy in one system. • The g-CPFD exhibits folate receptor-mediated targeting ability. • The g-CPFD is traceable and exhibits pH-responsive release property. Graphitic carbon nitride quantum dots (g-CNQDs) have shown great potential in imaging, drug delivery and photodynamic therapy (PDT). However, relevant research on g-CNQDs for PDT or drug delivery has been conducted separately. Herein, we develop a g-CNQDs-based nanoplatform (g-CPFD) to achieve simultaneously imaging and chemo-photodynamic combination therapy in one system. A g-CNQDs-based nanocarrier (g-CPF) is first prepared by successively introducing carboxyamino-terminated oligomeric polyethylene glycol and folic acid onto the surface of g-CNQDs via two-step amidation. The resultant g-CPF possesses good physiological stability, strong blue fluorescence, desirable biocompatibility, and visible light-stimulated reactive oxygen species generating ability. Further non-covalently loaded doxorubicin enables the system with chemotherapy function. Compared with free doxorubicin, g-CPFD expresses more efficient chemotherapy to HeLa cells due to improved folate receptor-mediated cellular uptake and intracellular pH-triggered drug release. Furthermore, g-CPFD under visible light irradiation shows enhanced inhibition on the growth of cancer cells compared to sole chemotherapy or PDT. Thus, g-CPFD exhibits exceptional anti-tumor efficiency due to folate receptor-mediated targeting ability, intracellular pH-triggered drug release and a combined treatment effect arising from PDT and chemotherapy. Moreover, this nanoplatform benefits imaging-guided drug delivery because of inherent fluorescent properties of doxorubicin and g-CPF, hence achieving the goal of imaging-guided chemo-photodynamic combination treatments. [ABSTRACT FROM AUTHOR]

In view of high ground stress, high geothermal temperature, and thermal hazard during deep mineral resource exploitation, the concept of phase-change heat storage backfill was put forward in this study. Further, the corresponding technical system was constructed and the main content involved in technical system, which is the optimized proportion of the backfill slurry added with phase-change materials (PCMs), was examined. Moreover, we elaborated upon the collaborative optimization of a backfill body's mechanical and thermal properties and the mutual cooperation on backfill mining, geothermal energy exploitation, and simultaneous stope cooling. The heat transfer behavior of a backfill body plays a key role in technology system. We numerically simulated the heat transfer among a backfill body, surrounding rock, and airflow in the heat storage process, as well as the heat transfer between backfill body and cold fluid during the heat release process. The temperature distribution of a backfill body at different heat storage/heat release times—i.e., the temperature distribution and its evolution—with heat transfer were revealed and analyzed. This study can provide theoretical guidance for a phase-change heat storage backfill, as it has an important significance for the collaborative exploitation of mineral resources and geothermal energy. [ABSTRACT FROM AUTHOR]

• A drug delivery system based on fluorescent MoS 2 QDs is synthesized. • PEGylated MoS 2 QDs has good physiological stability and is suitable for carrier. • The drug delivery system is traceable and exhibits pH-responsive release property. Since low pH value is widely observed in most of solid tumors, pH-responsive drug delivery system (DDS) can provide a general strategy for tumor-targeting therapy. In this work, a traceable and pH-responsive DDS (MoS 2 -PEG-DOX) based on MoS 2 quantum dots (MoS 2 QDs) is successfully developed by covalently grafting MoS 2 QDs with diamine-terminated oligomeric polyethylene glycol (PEG) and then loading with a fluorescent antineoplastic anthracycline drug, doxorubicin (DOX). The functionalization of MoS 2 QDs with PEG imparts the nanocomposite with strong blue photoluminescence, low cytotoxicity, and excellent physiological stability. The MoS 2 -PEG-DOX nano-assembly can be effectively taken up by U251 cells, and an accelerated DOX release is then triggered by intracellular acid condition, which in turn diminishing unwanted side effects derived by the incorporation of DOX into healthy cells. Meanwhile, the cellular uptake of the MoS 2 -PEG-DOX nano-assembly, consequent DOX release and the localization of nanocarrier can be real-time monitored due to the inherent stable fluorescence of MoS 2 -PEG and DOX. These findings demonstrate that MoS 2 -PEG-DOX will be promising for high treatment efficacy with minimal side effects in future therapy. [ABSTRACT FROM AUTHOR]