Centennial Records of Microplastics in Lake Cores in Huguangyan Maar Lake, China.

Microplastic records from lake cores can reconstruct the plastic pollution history. However, the associations between anthropogenic activities and microplastic accumulation are not well understood. Huguangyan Maar Lake (HML) is a deep-enclosed lake without inlets and outlets, where the sedimentary environment is ideal for preserving a stable and historical microplastic record. Microplastic (size: 10-500 µm) characteristics in the HML core were identified using the Laser Direct Infrared Imaging system. The earliest detectable microplastics appeared unit in 1955 (1.1 items g-1). The microplastic abundance ranged from n.d. to 615.2 items g-1 in 1955-2019 with an average of 134.9 items g-1. The abundance declined slightly during the 1970s and then increased rapidly after China's Reform and Opening Up in 1978. Sixteen polymer types were detectable, with polyethylene and polypropylene dominating, accounting for 23.5 and 23.3% of the total abundance, and the size at 10-100 µm accounted for 80%. Socioeconomic factors dominated the microplastic accumulation based on the random forest modeling, and the contributions of GDP per capita, plastic-related industry yield, and total crop yield were, respectively, 13.9, 35.1, and 9.3% between 1955-2019. The total crop yield contribution further increased by 1.7% after 1978. Coarse sediment particles increased with soil erosion exacerbated microplastics discharging into the sediment.

Immunosensors for C-Reactive Protein Based on Ultrathin Films of Carboxylated Cellulose Nanofibrils.

C-reactive protein (CRP) is an acute phase protein that has been widely used as a predictor of cardiovascular diseases. We report herein the synthesis of immunosensors based on carboxylated cellulose nanofibrils (CNF) for CRP detection, as demonstrated by quartz crystal microgravimetry (QCM). QCM sensors carrying ultrathin films of carboxylated CNF were prepared by using two protocols: (i) spin coating of CNF on the sensors followed by carboxylation via in situ oxidation with 2,2,6,6-tetramethylpiperidine 1-oxyl and (ii) carboxymethylation of CNF in aqueous dispersion followed by spin coating deposition on the sensors. Protein A was conjugated to the carboxylated CNF via N-(3-(Dimethylamino)propyl)-N'-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide and used as a ligand for oriented immobilization of anti C-reactive protein (anti-CRP). The different carboxyl group density of the two oxidized CNF surfaces influenced Protein A binding and, subsequently, the available immobilized anti-CRP molecules. The detection efficiency for CRP, specificity, and concentration range displayed by the carboxylated CNF-based immunosensors coupled with oriented and unoriented anti-CRP were determined and compared.

In Situ Photoactivated Antibacterial and Antioxidant Composite Materials to Promote Bone Repair.

Trauma and tumor removal usually cause bone defects; in addition, the related postoperative infection also shall be carefully considered clinically. In this study, polylactic acid (PLLA) composite fibers containing Cerium oxide (CeO2) are first prepared by electrospinning technology. Then, the PLLA/CeO2@PDA/Ag composite materials are successfully prepared by reducing silver ion (Ag+) to nano-silver (AgNPs)  coating in situ and binding AgNPs to the materials surface by mussel structure liked polydopamine (PDA). In the materials, Ag+ can be slowly released in simulated body fluids. Based on the photothermal performance of AgNPs, the photothermal conversion efficiency of the materials is 21%, under NIR 808 nm illumination. The effective photothermal conversion can help materials fighting with E. coli and S. aureus in 3 h, with an antibacterial rate of 100%. Additionally, the sustained Ag+ release contributes to the antibacterial in long term. Meanwhile, the materials can mimic the bio-behavior of superoxide dismutase and catalase in decreasing the singlet oxygen level and removing the excess reactive oxygen species. Furthermore, the materials are beneficial for cell proliferation and osteogenic differentiation in vitro. In this study, a promising bone-regenerated material with high photothermal conversion efficiency and antibacterial and anti-oxidation properties, is successfully constructed.

A Photothermal Polymeric Platform for Efficient and Safe Gene Transfection: When Polyethylenimine Collaborates with Indocyanine Green.

Gene transfection, defined by the delivery of nucleic acids into cellular compartments, stands as a crucial procedure in gene therapy. While branched polyethylenimine (PEI) is widely regarded as the "gold standard" for nonviral vectors, its cationic nature presents several issues, including nonspecific protein adsorption and notable cytotoxicity. Additionally, it often fails to achieve high transfection efficiency, particularly with hard-to-transfect cell types. To overcome these challenges associated with PEI as a vector for plasmid DNA (pDNA), the photothermal agent indocyanine green (ICG) is integrated with PEI and pDNA to form the PEI/ICG/pDNA (PI/pDNA) complex for more efficient and safer gene transfection. The negatively charged ICG serves a dual purpose: neutralizing PEI's excessive positive charges to reduce cytotoxicity and, under near-infrared irradiation, inducing local heating that enhances cell membrane permeability, thus facilitating the uptake of PI/pDNA complexes to boost transfection efficiency. Using pDNA encoding vascular endothelial growth factor as a model, our system shows enhanced transfection efficiency in vitro for hard-to-transfect endothelial cells, leading to improved cell proliferation and migration. Furthermore, in vivo studies reveal the therapeutic potential of this system in accelerating the healing of infected wounds by promoting angiogenesis and reducing inflammation. This approach offers a straightforward and effective method for gene transfection, showing potentials for tissue engineering and cell-based therapies.

Specific binding of immunoglobulin G with bioactive short peptides supported on antifouling copolymer layers for detection in quartz crystal microgravimetry and surface plasmon resonance.

A new peptide-based system supported on copolymer brushes grafted from gold sensors and with resistance to nonspecific adsorption is reported for selective binding of human immunoglobulin G (IgG). A random copolymer rich in primary amines, poly(2-aminoethyl methacrylate hydrochloride-co-2-hydroxyethyl methacrylate) (poly(AMA-co-HEMA)) was first grafted from initiator-coated gold substrates via activators regenerated by electron transfer-atom transfer radical polymerization (ARGET-ATRP), followed by immobilization of acetylated-HWRGWVA peptide, which has specific binding affinity with IgG. The peptide ligands covalently linked to the soft copolymer layer were characterized by X-ray photoelectron spectroscopy (XPS), water contact angle, ellipsometry, and atomic force microscopy (AFM). The extent of binding, binding affinity, and selectivity for target IgG molecules as well as the capability to minimize nonspecific interactions with other proteins were examined by fluorescence imaging, surface plasmon resonance (SPR), and quartz crystal microgravimetry (QCM). The effect of copolymer molecular composition and analyte concentration was elucidated in order to design systems based on immobilized peptides for high signal-to-noise response and detection limits that meet the requirements for IgG biosensing in fluid matrixes.

Bioactive cellulose nanofibrils for specific human IgG binding.

Bioactive films were produced by conjugation of a short peptide onto modified cellulose nanofibrils (CNF). Specifically, a hydrophilic copolymer, poly(2-aminoethyl methacrylate hydrochloride-co-2-hydroxyethylmethacrylate) (poly(AMA-co-HEMA)), was grafted via surface initiated polymerization from an initiator coupled to CNF. The poly(AMA-co-HEMA) was used as a spacer and support layer for immobilization of the peptide, acetylated-HWRGWVA, which has specific affinity with human immunoglobulin G (hIgG). Two methods for peptide grafting were compared: modification of CNF in aqueous suspension followed by assembly into a bioactive film and peptide grafting on a preformed CNF film. The CNF-based networks were examined on solid supports via atomic force microscopy (AFM) and extreme resolution imaging with ultralow electron landing energies (scanning low energy electron microscopy). The specific binding capability of hIgG and nonspecific protein resistance of the resultant peptide-modified CNF were evaluated by using quartz crystal microgravimetry (QCM). The effects of initiator concentration and thickness of poly(AMA-co-HEMA) layer on hIgG adsorption were investigated in the developed systems, which exhibited high signal-to-noise response.

Abundances of agricultural microplastics and their contribution to the soil organic carbon pool in plastic film mulching fields of Xinjiang, China.

Plastic mulched agricultural fields in Xinjiang are regarded as potential "hotspots" of microplastic (MP) contamination in China, whereas the abundance of MPs in this region is still unclear. As a carbonaceous material, current conventional methods for measuring soil organic carbon (SOC) generally do not separate the MPs from soils, which probably overestimated the soil carbon (C) sequestration. In this study, 77 agricultural soil samples under plastic film mulching were collected in Xinjiang. Afterward, the average abundance of agricultural MPs and the contribution of microplastic-carbon (MP-C) to the SOC pool were evaluated. The abundance of MPs was 12,589 pieces kg-1 soil (ranging from 4198 to 47,420 pieces kg-1 soil), and small-sized (<0.5 mm) plastic particles accounted for 93.3% of the total MPs. Interestingly, the soil salt content was positively related to the proportion of 0.1-0.5 mm MP but negatively correlated with the proportion of 0.02-0.1 mm MP, indicating that soil salinization probably controlled the degradation process of plastic residues. The average content of MP-C in the 0-20 cm layer was 25.33 kg ha-1 (ranging from 1.60 to 192.57 kg ha-1), which had a contribution of 1.59‰ (ranging from 0.05 to 14.24‰) to the SOC pool. Accordingly, we roughly estimated that the MP-C storage (0-20 cm layer) was approximately 88.66 Gg in the plastic film mulching fields of Xinjiang. Although MP is undeniably organic C, this environmental pollution cannot be regarded as "true" soil C storage, which induces the overestimation of soil C sequestration in agricultural fields. Therefore, our results highlighted that MP-C should be subtracted when estimating SOC sequestration in plastic film mulching fields of Xinjiang.

Multifunctional coatings based on candle soot with photothermal bactericidal property and desired biofunctionality.

Functional coatings with desired bioactivities are required for various biomedical applications. Candle soot (CS) composed of carbon nanoparticles has attracted significant attention as a versatile component of functional coatings because of its unique physical and structural characteristics. However, the application of CS-based coatings in the biomedical field is still limited due to the lack of modification methods that can endow them with specific biofunctionality. Herein, a facile and widely applicable approach to fabricate multifunctional CS-based coatings is developed by grafting functional polymer brushes on the silica-stabilized CS. The resulting coatings not only exhibited excellent near-infrared-activated biocidal ability (the killing efficiency was over 99.99 %) due to the inherent photothermal property of CS but also showed desired biofunctions (such as antifouling property or controllable bioadhesion; the repelling efficiency and bacterial release ratio were nearly 90 %) originated from the grafted polymers. Moreover, these biofunctions were enhanced by the nanoscale structure of CS. Because the deposition of CS is a simple substrate-independent process while the grafting of polymer brushes via surface-initiated polymerization is applicable to a wide range of vinyl monomers, the proposed approach can be potentially used for the fabrication of multifunctional coatings and would extend the applications of CS in the biomedical field.

Injectable Decellularized Extracellular Matrix Hydrogel Containing Stromal Cell-Derived Factor 1 Promotes Transplanted Cardiomyocyte Engraftment and Functional Regeneration after Myocardial Infarction.

Transplantation of exogenous cardiomyocytes (CMs) is a hopeful method to treat myocardial infarction (MI). However, its clinical application still remains challenging due to low retention and survival rates of the transplanted cells. Herein, a stromal cell-derived factor 1 (SDF-1)-loaded injectable hydrogel based on a decellularized porcine extracellular matrix (dECM) is developed to encapsulate and deliver CMs locally to the infarct area of the heart. The soluble porcine cardiac dECM is composed of similar components such as the human cardiac ECM, which could be self-assembled into a nanofibrous hydrogel at physiological temperature to improve the retention of transplanted CMs. Furthermore, the chemokine SDF-1 could recruit endogenous cells to promote angiogenesis, mitigating the ischemic microenvironment and improving the survival of CMs. The results in vitro show that this composite hydrogel exhibits good biocompatibility, anti-apoptosis property, and chemotactic effects for mesenchymal stromal cells and endothelial cells through SDF-1-CXCR4 axis. Moreover, intramyocardial injection of this composite hydrogel to the infarcted area leads to the promotion of angiogenesis and inhibition of fibrosis, reducing the infarction size and improving the cardiac function. The combination of natural biomaterials, exogenous cells, and bioactive factors shows potential for MI treatment in the clinical application.

Surveillance, epidemiology, and impact of the coronavirus disease 2019 interventions on the incidence of enterovirus infections in Nanchang, China, 2010-2022.

Introduction: Pathogen spectrum of Hand, foot and mouth disease (HFMD) has substantially changed in the past decade in China. Growing evidence has indicated that anti-COVID-19 nonpharmaceutical interventions (NPIs) can support control of various infectious diseases, including intestinal diseases. Methods: In this study, HFMD cases were enrolled from sentinel hospitals of Nanchang, Jiangxi province, and enteroviruses were genotyped using specific real time RT-PCR. We systematically characterized the epidemiology of HFMD based on the continuous molecular surveillance and estimated the impact of COVID-19 intervention on HFMD incidence using seasonal autoregressive integrated moving average (ARIMA) models. Results: A total of 10247 HFMD cases were included during 2010-2022, of which 6121 enterovirus (EV)-positive cases (59.7%) were identified by real-time RT-PCR. Over 80% cases were associated with EV-A71 and coxsackievirus A16 (CVA16) during 2010-2012, while the type distribution significantly changed as CVA6 emerged to be dominant, accounting for 22.6%-59.6% during 2013-2022. It was observed that the prevalence patterns of EV-A71 and CVA16 were similar and both of them peaked in the second quarter and then leveled off. However, CVA6 was generally prevalent around the fourth quarter, demonstrating a staggered prevalence during 2010-2019. During the COVID-19 epidemic, the seasonal HFMD epidemic peak was restrained, and the ARIMA analysis indicated that the COVID-19 intervention had mitigated EV transmission during the first COVID-19 outbreak in early 2020. In addition, bivariate Spearman's cross-correlation coefficients were estimated for the major types CVA6, CVA16 and EV-A71. Our analyses indicated the possible existence of correlations among CVA6, CVA16 and EV-A71 prevalence in the epidemiological level. Discussion: Taken together, the type distribution of HFMD has substantially changed over the last decade and CVA6 and CVA16 are currently the most predominant types co-circulating in Nanchang. The anti-COVID-19 NPIs significantly reduced the incidence of EV infections.

Effects of microplastics on soil carbon dioxide emissions and the microbial functional genes involved in organic carbon decomposition in agricultural soil.

The accumulation of microplastics (MPs) in agricultural fields can not only disguise soil organic carbon (SOC) storage but also affect the production of carbon dioxide (CO2) by microbial decomposition. However, little is known about the impact of this emerging pollutant on soil CO2 emissions and the functional genes related to SOC degradation. In the present study, a short-term (30-day) microcosm experiment was performed to investigate the effects of virgin and aged low-density polyethylene (LDPE) MPs on soil CO2 emissions. We also measured functional gene abundances related to starch (sga), hemicellulose (abfA, manB and xylA), cellulose (cex) and lignin (lig and mnp) degradation through a high-throughput quantitative-PCR-based chip. Compared with the soils without MPs, low doses (0.01% and 0.1%) of both virgin and aged MPs had negligible effects on SOC decomposition, whereas a high dose (1.0%) of these two MPs significantly (p < 0.05) accelerated the production of CO2 in soils by 15-17%, showing a dose-dependent effect. The presence of MPs did not significantly affect soil dissolved organic carbon or microbial biomass carbon. A higher metabolic quotient at 1.0% MP concentration indicated that the microbes were stressed and needed more substrates and energy during their metabolic process, which could likely explain the increase in CO2 emission induced by this dose of MPs. Exposure to virgin MPs significantly reduced the functional genes related to hemicellulose (abfA and manB) degradation, whereas increasing the aged MPs concentrations significantly decreased the abundances of functional genes encoding starch (sga), hemicellulose (abfA, manB and xylA), and cellulose (cex) hydrolysis. Overall, we conclude that the low dose (<0.1%) of MPs in the soils has a negligible effect on the production of CO2, but this factor should be considered in evaluating the global C budget in future research as this contaminant reaches a certain threshold (1.0%).

A Photothermal Nanoplatform with Sugar-Triggered Cleaning Ability for High-Efficiency Intracellular Delivery.

Intracellular delivery of functional molecules is of great importance in various biomedical and biotechnology applications. Recently, nanoparticle-based photothermal poration has attracted increasing attention because it provided a facile and efficient method to permeabilize cells transiently, facilitating the entry of exogenous molecules into cells. However, this method still has some safety concerns associated with the nanoparticles that bind to the cell membranes or enter the cells. Herein, a nanoplatform with both photothermal property and sugar-triggered cleaning ability for intracellular delivery is developed based on phenylboronic acid (PBA) functionalized porous magnetic nanoparticles (named as M-PBA). The M-PBA particles could bind to the target cells effectively through the specific interactions between PBA groups and the cis-diol containing components on the cell membrane. During a short-term near-infrared irradiation, the bound particles convert absorbed light energy to heat, enabling high-efficiency delivery of various exogenous molecules into the target cells via a photothermal poration mechanism. After delivery, the bound particles could be easily "cleaned" from the cell surface via mild sugar-treatment and collected by a magnet, avoiding the possible side effects caused by the entrance of particles or their fragments. The delivery and cleaning process is short and effective without compromising the viability and proliferation ability of the cells with delivered molecules, suggesting that the M-PBA particles could be used as promising intracellular delivery agents with a unique combination of efficiency, safety, and flexibility.

Phthalate pollution and migration in soil-air-vegetable systems in typical plastic agricultural greenhouses in northwestern China.

Phthalate pollution in plastic greenhouses (PGs) has aroused concerns. However, mechanisms and factors of vegetables planted in PGs (VPGs) accumulating phthalates from soil and air are unclear. To fill the gap, 19 PGs in Shaanxi, the largest vegetable production province in northwestern China, were selected to probe this issue. 35 soil samples, 48 air samples, and 26 VPG samples were collected in winter and summer. Medians of sum of 7 phthalate concentrations (∑7 PAEs) in PG soil, air, and VPGs were 73.9 µg kg-1, 5300 ng m-3, and 1053 µg kg-1 dry weight, respectively. ∑7 PAE concentrations in PG environmental media in winter were higher than summer, with the significant difference in VPGs. Sum concentrations of bis (2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DnBP) accounted for 76.8% and 82.3% of the ∑7 PAEs in soil and VPGs. DnBP and DEHP concentrations in VPGs were significantly correlated to those in air and soil, with correlation coefficients (R) of 0.89 and 0.96 to air and 0.68 and 0.59 to soil. Log-transformed soil-air partition coefficient (log KSA) and fugacity fraction (log ff) of DnBP decreased while log KSA and log ff of DEHP increased from winter to summer, though DnBP in soil volatilized to air while DEHP in air sank to soil within the year. These issues were caused by air temperature changes and the application of plastic films. Furthermore, DnBP concentrations in VPGs were positively correlated to KSA values of DnBP (R = 0.87) while those of DEHP were negative (R = -0.82). Therefore, VPGs could uptake more phthalates from air than from soil, especially for edible parts of leafy and solanaceous VPGs. Applying phthalates free agricultural films and precision management such as adjusting air temperature in PGs could be considered to ensure VPG safeties.

Charcot-Marie-Tooth Disease With Episodic Rhabdomyolysis Due to Two Novel Mutations in the ß Subunit of Mitochondrial Trifunctional Protein and Effective Response to Modified Diet Therapy.

A 29-year-old female experienced chronic progressive peripheral neuropathy since childhood and was diagnosed with Charcot-Marie-Tooth disease (CMT) at age 15. She developed recurrent, fever-induced rhabdomyolysis (RM) at age 24. EMG studies showed decreased amplitude of compound muscle action potential, declined motor conductive velocity, and absence of sensor nerve action potential. Acylcarnitine analysis revealed elevated C16-OH, C18-OH, and C18:1-OH. Muscle biopsy showed scattered foci of necrotic myofibers invaded by macrophages, occasional regenerating fibers, and remarkable muscle fiber type grouping. Whole-exome sequencing identified two novel heterozygous mutations: c.490G>A (p.G164S) and c.686G>A (p.R229Q) in HADHB gene encoding the ß-subunit of mitochondrial trifunctional protein (MTP). Reduction of long-chain fatty acid via dietary restrictions alleviated symptoms effectively. Our study indicates that the defect of the MTP ß-subunit accounts for both CMT and RM in the same patient and expands the clinical spectrum of disorders caused by the HADHB mutations. Our systematic review of all MTPD patients with dietary treatment indicates that the effect of dietary treatment is related to the age of onset and the severity of symptoms.

Urinary phthalate metabolites among workers in plastic greenhouses in western China.

Agricultural plastic greenhouse (PG) production can extend the growing season of crops to satisfy domestic consumption in countries such as China. Workers in PGs have potential higher phthalate exposure risks than the general population as phthalate accumulation has been observed in greenhouse soil, air, and crops. To date, biomonitoring tests of phthalates for the working population have not been carried out. To address this shortage, we conducted a pilot study in Shaanxi Province, China, among 35 healthy PG workers by follow-up recording their seasonal dietary habits and work activities and urine sample collection and measurement between 2018 and 2019. The objectives were to uncover the association between phthalate metabolites and the population characteristics, seasonal and diurnal variations and causes, and to estimate exposure risks and contributions of exposure pathways from PG production systems. A total of 13 phthalate metabolite concentrations (Σ13 phthalate metabolites) ranged from 102 to 781 (5th-95th) ng/mL (median: 300 ng/mL). Mono-n-butyl phthalate (MNBP) made up 51.3% of Σ13 phthalate metabolites, followed by the sum of four di-2-ethylhexyl phthalate (DEHP) metabolites (24.2%), mono-2-isobutyl phthalate (MIBP) (13.4%), and mono-ethyl phthalate (MEP) (9.8%). The concentrations of MNBP and MIBP in summer were significantly higher than the levels in winter (p < 0.0001). A total of 62.3% of the PG worker population was shown to have exposure risks, and the proportion was as high as 79.4% in summer. Phthalate exposure of the workers from PG production systems constituted over 20% of the total creatinine-based daily intake, and consuming vegetables and fruit planted in PGs and inhalation in PGs were the two largest exposure pathways. Our findings demonstrate that it is important to protect workers in PGs from phthalate exposure risks, and phasing out the use of plastic materials containing phthalates in PGs is imperative, to guarantee food safety in PGs.

Atmospheric phthalate pollution in plastic agricultural greenhouses in Shaanxi Province, China.

Phthalate pollution in soil and vegetables in plastic agricultural greenhouses has attracted wide concern. Investigating airborne phthalates in this environment can improve understanding of air-soil or air-vegetable phthalate migration. However, studies of phthalates in plastic agricultural greenhouse air are rare. To fill this gap, 25 gas-phase and 23 particle-phase samples were collected from 12 typical plastic greenhouses in Shaanxi. 16 types of phthalates were measured by a gas chromatography-mass spectrometry system (GC-MS) to analyse their pollution features and variations. Results showed that in the air of the plastic greenhouses, the median concentration of the sum of sixteen type phthalates (∑16 phthalates) was 5305 ng m-3, with 5th-95th value of 1214-9616 ng m-3. Phthalates in gas-phase samples were over 100 times higher than the levels in particle-phase samples. Air phthalate concentrations in the plastic greenhouses were higher than those in the control groups (P < 0.05). Air bis (2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DnBP) accounted for 66.9% and 29.3% of total ∑16 phthalate concentrations, respectively. Air phthalate concentrations in the plastic greenhouses in winter were 1.1-5.3 times higher than the levels in summer respectively (P < 0.05). Gas-particle partition coefficients (KP) values of DEHP in summer (median of 1.52 × 10-4 m3 µg-1) were higher than KP values of DnBP in summer (0.60 × 10-4 m3 µg-1). Log-transformed KP values of DnBP and DEHP were linear correlated to the reciprocal of air temperatures, respectively (P < 0.05).

Surveillance, Epidemiology and Impact of EV-A71 Vaccination on Hand, Foot, and Mouth Disease in Nanchang, China, 2010-2019.

After the first national-scale outbreak of Hand, foot, and mouth disease (HFMD) in China, a national surveillance network was established. Here we described the epidemiology and pathogenic profile of HFMD and the impact of EV-A71 vaccination on pathogen spectrum of enteroviruses in the southeastern Chinese city of Nanchang during 2010-2019. A total of 7,951 HFMD cases from sentinel hospitals were included, of which 4,800 EV-positive cases (60.4%) were identified by real-time RT-PCR. During 2010-2012, enterovirus 71 (EV-A71) was the main causative agent of HFMD, causing 63.1% of cases, followed by 19.3% cases associated with coxsackievirus A16 (CV-A16). Since 2013, the proportion of other enteroviruses has increased dramatically, with the sub genotype D3 strain of Coxsackievirus A6 (CV-A6) replacing the dominance of EV-A71. These genetically diverse native strains of CV-A6 have co-transmitted and co-evolved in Nanchang. Unlike EV-A71 and CV-A16, most CV-A6 infections were concentrated in autumn and winter. The incidence of EV-A71 infection negatively correlated with EV-A71 vaccination (r = -0.990, p = 0.01). And severe cases sharply declined as the promotion of EV-A71 vaccines. After 2-year implementation of EV-A71 vaccination, EV-A71 is no longer detected from the reported HFMD cases in Nanchang. In conclusion, EV-A71 vaccination changed the pattern of HFMD epidemic, and CV-A6 replaced the dominance of EV-A71 over time.

Universal Antifouling and Photothermal Antibacterial Surfaces Based on Multifunctional Metal-Phenolic Networks for Prevention of Biofilm Formation.

Biofilms formed from the pathogenic bacteria that attach to the surfaces of biomedical devices and implantable materials result in various persistent and chronic bacterial infections, posing serious threats to human health. Compared to the elimination of matured biofilms, prevention of the formation of biofilms is expected to be a more effective way for the treatment of biofilm-associated infections. Herein, we develop a facile method for endowing diverse substrates with long-term antibiofilm property by deposition of a hybrid film composed of tannic acid/Cu ion (TA/Cu) complex and poly(ethylene glycol) (PEG). In this system, the TA/Cu complex acts as a multifunctional building block with three different roles: (i) as a versatile "glue" with universal adherent property for substrate modification, (ii) as a photothermal biocidal agent for bacterial elimination under irradiation of near-infrared (NIR) laser, and (iii) as a potent linker for immobilization of PEG with inherent antifouling property to inhibit adhesion and accumulation of bacteria. The resulted hybrid film shows negligible cytotoxicity and good histocompatibility and could prevent biofilm formation for at least 15 days in vitro and suppress bacterial infection in vivo, showing great potential for practical applications to solve the biofilm-associated problems of biomedical materials and devices.

Dual-Functional Surfaces Based on an Antifouling Polymer and a Natural Antibiofilm Molecule: Prevention of Biofilm Formation without Using Biocides.

Pathogenic biofilms formed on the surfaces of implantable medical devices and materials pose an urgent global healthcare problem. Although conventional antibacterial surfaces based on bacteria-repelling or bacteria-killing strategies can delay biofilm formation to some extent, they usually fail in long-term applications, and it remains challenging to eradicate recalcitrant biofilms once they are established and mature. From the viewpoint of microbiology, a promising strategy may be to target the middle stage of biofilm formation including the main biological processes involved in biofilm development. In this work, a dual-functional antibiofilm surface is developed based on copolymer brushes of 2-hydroxyethyl methacrylate (HEMA) and 3-(acrylamido)phenylboronic acid (APBA), with quercetin (Qe, a natural antibiofilm molecule) incorporated via acid-responsive boronate ester bonds. Due to the antifouling properties of the hydrophilic poly(HEMA) component, the resulting surface is able to suppress bacterial adhesion and aggregation in the early stages of contact. A few bacteria are eventually able to break through the protection of the anti-adhesion layer leading to bacterial colonization. In response to the resulting decrease in the pH of the microenvironment, the surface could then release Qe to interfere with the microbiological processes related to biofilm formation. Compared to bactericidal and anti-adhesive surfaces, this dual-functional surface showed significantly improved antibiofilm performance to prevent biofilm formation involving both Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus for up to 3 days. In addition, both the copolymer and Qe are negligibly cytotoxic, thereby avoiding possible harmful effects on adjacent normal cells and the risk of bacterial resistance. This dual-functional design approach addresses the different stages of biofilm formation, and (in accordance with the growth process of the biofilm) allows sequential activation of the functions without compromising the viability of adjacent normal cells. A simple and reliable solution may thus be provided to the problems associated with biofilms on surfaces in various biomedical applications.

pH-reversible, high-capacity binding of proteins on a substrate with nanostructure.

In this letter, a pH-switchable system for protein adsorption and release is introduced. By combining the pH sensitivity of poly(methacrylic acid) (poly(MAA) chains and the nanoeffects of 3D nanostructured silicon nanowire arrays (SiNWAs), a poly(MAA)-modified SiNWAs material showed an extremely high capacity for binding lysozyme at pH 4 (an ∼80-fold increase compared with that of smooth Si-poly(MAA)). Moreover, ∼90% of the adsorbed lysozyme was released from SiNWAs-poly(MAA) by increasing the pH from 4 to 9, without a loss of enzyme activity.