A novel ultra-low-volume regimen combining 1 L polyethylene glycol and linaclotide versus 2 L polyethylene glycol for colonoscopy cleansing in low-risk individuals: a randomized controlled trial.

BACKGROUND AND AIMS: The single dose of 2 L polyethylene glycol (PEG) has shown high cleaning efficacy and tolerability in low-risk patients. However, the dosage of this regimen is still challenging for many patients. We investigated the efficacy and tolerability of a novel ultra-low-volume regimen using 1 L PEG and linaclotide (1 L PEG+L) versus a single dose of 2 L PEG in low-risk patients. METHODS: In this prospective, randomized, observer-blinded, multicenter study, low-risk adult patients scheduled for colonoscopy were enrolled and randomized (1:1) to receive the 1 L PEG+L regimen or the 2 L PEG regimen. The primary outcome was the effectiveness of bowel cleansing according to the Boston Bowel Preparation Scale. Secondary outcomes included cecal intubation rate, cecal insertion time, withdrawal time, polyp detection rate and adenoma detection rate, tolerability, adverse events, and willingness to repeat bowel preparation. The full analysis set (FAS) and per-protocol set (PPS) were used for statistical analyses. RESULTS: A total of 548 patients comprised the FAS, and 522 patients comprised the PPS. Noninferiority on adequate bowel cleansing of 1 L PEG+L vs 2 L PEG was established both in FAS (90.5% vs 91.6%, P = .644) and PPS (90.3% vs 92.4%, P = .390). There were no significant differences regarding the total score and each segment scores of the Boston Bowel Preparation Scale, cecal intubation rate, cecal insertion time, withdrawal time, polyp detection rate, and adenoma detection rate (all, P > .05). However, patients in the 1 L PEG+L group reported less nausea (7.7% vs 17.1%, P < .01) and vomiting (4.0% vs 10.9%, P < .01) and had a higher willingness to repeat bowel preparation (95.2% vs 82.2%, P < .01). CONCLUSIONS: The regimen of 1 L PEG+L was not inferior to 2 L PEG on colon cleansing, with better tolerability and higher willingness to repeat the bowel preparation in a low-risk population. (Clinical trial registration number: ChiCTR2100053273.).

Design and Synthesis of Novel Bio-Based Polyester Elastomer with Tunable Oil Resistance.

Polarity determines the oil resistance property of elastomers. In this work, three bio-based polyester elastomers (BPEs) with different mass fraction of ester groups (E) are designed and synthesized aiming to study the relationship of E and oil resistance performance, and to obtain bio-based elastomer materials with tunable oil resistance. Through adjusting the chain length of monomers, E of poly(ethylene glycol/1,3-propanediol/succinate/adipate/itaconate)(PEPSAI), poly(1,3-propanediol/1,4-butanediol/succinate/adipate/itaconate)(PPBSAI), and poly(1,3-propanediol/1,4-butanediol/sebacate/adipate/itaconate)(PPBSeAI) are ≈50.39%, 48.55%, and 39.68%, respectively. Results show that E has great influence on the oil resistance of BPEs. After being immersed in IRM-903# oil for 72 h at room temperature, the changes in mass and volume of BPEs decrease along with the increasing mass fraction of ester groups, indicating improved oil resistance performance. PEPSAI with the highest mass fraction of ester groups presents better oil resistance and lower Tg (better low-temperature resistance) than one of the most used commercial oil-resistant rubber nitrile rubber (N230S). Thus, this work provides a promising strategy to obtain bio-based oil resistant elastomers with practical value.

Effects of the Preferential Oxidation of Phenolic Lignin Using Chlorine Dioxide on Pulp Bleaching Efficiency.

Chlorine dioxide is widely used for pulp bleaching because of its high delignification selectivity. However, efficient and clean chlorine dioxide bleaching is limited by the complexity of the lignin structure. Herein, the oxidation reactions of phenolic (vanillyl alcohol) and non-phenolic (veratryl alcohol) lignin model species were modulated using chlorine dioxide. The effects of chlorine dioxide concentration, reaction temperature, and reaction time on the consumption rate of the model species were also investigated. The optimal consumption rate for the phenolic species was obtained at a chlorine dioxide concentration of 30 mmol·L-1, a reaction temperature of 40 °C, and a reaction time of 10 min, resulting in the consumption of 96.3% of vanillyl alcohol. Its consumption remained essentially unchanged compared with that of traditional chlorine dioxide oxidation. However, the consumption rate of veratryl alcohol was significantly reduced from 78.0% to 17.3%. Additionally, the production of chlorobenzene via the chlorine dioxide oxidation of veratryl alcohol was inhibited. The structural changes in lignin before and after different treatments were analyzed. The overall structure of lignin remained stable during the optimization of the chlorine dioxide oxidation treatment. The signal intensities of several phenolic units were reduced. The effects of the selective oxidation of lignin by chlorine dioxide on the pulp properties were analyzed. Pulp viscosity significantly increased owing to the preferential oxidation of phenolic lignin by chlorine dioxide. The pollution load of bleached effluent was considerably reduced at similar pulp brightness levels. This study provides a new approach to chlorine dioxide bleaching. An efficient and clean bleaching process of the pulp was developed.

Super Stretchable and Compressible Hydrogels Inspired by Hook-and-Loop Fasteners.

Inspired by hook-and-loop fasteners, we designed a hydrogel network containing α-zirconium phosphate (ZrP) two-dimensional nanosheets with a high density of surface hydroxyl groups serving as nanopatches with numerous "hooks," while polymer chains with plentiful amine functional groups serve as "loops." Our multiscale molecular simulations confirm that both the high density of hydroxyl groups on nanosheets and the large number of amine functional groups on polymer chains are essential to achieve reversible interactions at the molecular scale, functioning as nano hook-and-loop fasteners to dissipate energy. As a result, the synthesized hydrogel possesses superior stretchability (>2100% strain), resilience to compression (>90% strain), and durability. Remarkably, the hydrogel can sustain >5000 cycles of compression with torsion in a solution mimicking synovial fluid, thus promising for potential biomedical applications such as artificial articular cartilage. This hook-and-loop model can be adopted and generalized to design a wide range of multifunctional materials with exceptional mechanical properties.

PCR-RFLP for Detection of Fusarium graminearum Genotypes with Resistance to Phenamacril.

Phenamacril is a cyanoacrylate fungicide that provides excellent control of Fusarium head blight (FHB) or wheat scab, which is caused predominantly by Fusarium graminearum and F. asiaticum. Previous studies revealed that codon mutations of the myosin-5 gene of Fusarium spp. conferred resistance to phenamacril in in vitro lab experiments. In this study, PCR restriction fragment length polymorphism (RFLP) was developed to detect three common mutations (A135T, GCC to ACC at codon 135; S217L, TCA to TTA at codon 217; and E420K, GAA to AAA at codon 420) in F. graminearum induced by fungicide domestication in vitro. PCR products of 841 bp (for mutation of A135T), 802 bp (for mutation of S217L), or 1,649 bp (for mutation of E420K) in the myosin-5 gene were amplified by appropriate primer pairs. Restriction enzyme KpnI, TasI, or DraI was used to distinguish phenamacril-sensitive and -resistant strains with mutation genotypes of A135T, S217L, and E420K, respectively. KpnI digested the 841-bp PCR products of phenamacril-resistant strains with codon mutation A135T into two fragments of 256 and 585 bp. In contrast, KpnI did not digest the PCR products of sensitive strains. TasI digested the 802-bp PCR products of phenamacril-resistant strains with codon mutation S217L into three fragments of 461, 287, and 54 bp. In contrast, TasI digestion of the 802-bp PCR products of phenamacril-sensitive strains resulted in only two fragments of 515 and 287 bp. DraI digested the 1,649-bp PCR products of phenamacril-resistant strains with codon mutation E420K into two fragments of 932 and 717 bp, while the PCR products of phenamacril-sensitive strains was not digested. The three genotypes of resistance mutations were determined by analyzing electrophoresis patterns of the digestion fragments of PCR products. The PCR-RFLP method was evaluated on 48 phenamacril-resistant strains induced by fungicide domestication in vitro and compared with the conventional method (mycelial growth on fungicide-amended agar). The accuracy of the PCR-RFLP method for detecting the three mutation genotypes of F. graminearum resistant to phenamacril was 95.12% compared with conventional method. Bioinformatics analysis revealed that the PCR-RFLP method could also be used to detect the codon mutations of A135T and E420K in F. asiaticum.

Single-atom Fe catalytic amplification-gold nanosol SERS/RRS aptamer as platform for the quantification of trace pollutants.

Bisphenol A (BPA), as a typical endocrine disruptor, poses a serious threat to human health. Therefore, it is urgent to establish a rapid, sensitive, and simple method for the determination of BPA. In this paper, based on the aptamer-mediated single-atom Fe carbon dot catalyst (SAFe) catalyzing the HAuCl4-ethylene glycol (EG) nanoreaction, a new SERS/RRS di-mode detection method for BPA was established. The results show that SAFe exhibits a strong catalytic effect on the HAuCl4-EG nanoreaction, which could generate purple gold nanoparticles (AuNPs) with resonance Rayleigh scattering (RRS) signals and surface-enhanced Raman scattering (SERS) effects. After the addition of BPA aptamer (Apt), it could encapsulate SAFe through intermolecular interaction, thus inhibiting its catalytic action, resulting in the reduction of AuNPs generated and the decrease of RRS and SERS signals of the system. With the addition of BPA, Apt was specifically combined with BPA, and SAFe was re-released to restore the catalytic ability; the generated AuNPs increased. As a result of this RRS and SERS signals of the system recovered, and their increment was linear with the concentration of BPA. Thus, the quantification of 0.1-4.0 nM (RRS) and 0.1-12.0 nM (SERS) BPA was realized, and the detection limits were 0.08 nM and 0.03 nM, respectively. At the same time, we used molecular spectroscopy and electron microscopy to study the SAFe-HAuCl4-ethylene glycol indicator reaction, and proposed a reasonable SAFe catalytic reaction mechanism. Based on Apt-mediated SAFe catalysis gold nanoreaction amplification, a SERS/RRS di-mode analytical platform was established for targets such as BPA.

Fluorescence Sensor Based on Biosynthetic CdSe/CdS Quantum Dots and Liposome Carrier Signal Amplification for Mercury Detection.

Mercury (Hg), as a highly harmful environmental pollutant, poses severe ecological and health risks even at low concentrations. Accurate and sensitive methods for detecting Hg2+ ions in aquatic environments are highly needed. In this work, we developed a highly sensitive fluorescence sensor for Hg2+ detection with an integrated use of biosynthetic CdSe/CdS quantum dots (QDs) and liposome carrier signal amplification. To construct such a sensor, three single-stranded DNA probes were rationally designed based on the thymine-Hg2+-thymine (T-Hg2+-T) coordination chemical principles and by taking advantage of the biocompatibility and facile-modification properties of the biosynthetic QDs. Hg2+ could be determined in a range from 0.25 to 100 nM with a detection limit of 0.01 nM, which met the requirements of environmental sample detection. The sensor also exhibited a high selectivity for Hg2+ detection in the presence of other high-level metal ions. A satisfactory capacity of the sensor for detecting environmental samples including tap water, river water, and landfill leachate was also demonstrated. This work opens up a new application scenario for biosynthetic QDs and holds a great potential for environmental monitoring applications.

Torque expression by active and passive self-ligating brackets in patients with four premolar extractions: A retrospective study.

OBJECTIVE: Appropriate torque expression contributes to ideal treatment outcomes both clinically and aesthetically. Whether active and passive self-ligating brackets (SLBs) have different torque-control capability in vivo has never been reported. The purpose of present study was to explore whether there was difference in torque expression in active and passive SLBs. SETTING AND SAMPLE POPULATION: In this retrospective study, 225 patients with four first premolar extractions were enrolled. For each patient, the digital lateral cephalometric radiographs were taken before and after treatment. MATERIALS AND METHODS: The study consisted of 2 groups: 111 subjects were treated with passive SLBs (Damon Q, Ormco) and 114 subjects with active SLBs (Empower 2, American Orthodontics). Measurements to determine skeletal changes and incisor inclination were obtained from cephalometric tracings using Dolphin software (version 11.8, USA). Comparisons in both groups and intergroups were compared using t tests and chi-square test. RESULTS: Significant differences in the variation of U1-SN(°), U1-NA(°), L1-NB(°) and L1-FH(°) were found between two groups. More labially inclined maxillary incisors were found in active SLB group, while more labially inclined mandibular incisors were observed in passive SLB group. CONCLUSIONS: With the present prescription set in the two brackets, active SLBs achieved more proclined maxillary incisors and retroclined mandibular incisors. Clinicians should take torque expression of brackets into consideration during orthodontic treatment.

Treatment in a patient with congenital loss of both mandibular lateral incisors and severely retroclined maxillary central incisors.

This case report describes the treatment of a patient with congenital loss of both mandibular lateral incisors and severely retroclined maxillary incisors. The treatment included bilateral extraction of the maxillary first premolars, accurate 3-digital setup, a 2-stage torque control strategy, and intricate mechanic management. The dilemma of tooth-size discrepancy was solved by ideal torque control to avoid interproximal enamel reduction. An ideal Class I molar and canine relation, as well as canine guidance in the lateral excursion movement, was achieved with good stability.

[Influence of Meteorological Factors on HFMD and Construction of Prediction Model in Sichuan Province].

OBJECTIVE: To analyze the epidemiological characteristics of hand, foot and mouth disease (HFMD) in Sichuan Province from 2013 to 2019. To study the correlation between meteorological factors and the incidence of HFMD and construct a prediction model. METHODS: The HMFD surveillance data and meteorological data from 2013 to 2019 in Sichuan Province were collected through the Chinese Center for Disease Control and Prevention and the China Meteorological data Network. Spearman correlation was used to analyze the relationship between HFMD incidence and meteorological factors. Multiple regression model and support vector regression (SVR) model were used to construct HFMD incidence prediction models respectively. RESULTS: A total of 615 840 cases of HFMD and 81 deaths were reported from 2013 to 2019. The average annual incidence rate was 107.31/105, and the mortality rate was 0.16/106. Spearman correlation analysis showed that the monthly incidence rate of HFMD was correlated with monthly average relative humidity (r=0.342), monthly average temperature (r=0.284), monthly average water vapor pressure (r=0.304) and monthly average days of precipitation (r=0.259). The prediction effect of the SVR model (R2=0.836) was better than the multiple regression model (R2=0.375). The SVR model provided a good fit to the monthly incidence of HFMD from 2013 to 2018, and can predict the peak incidence of HFMD in 2019. CONCLUSION: Relative humidity has the greatest influence on the incidence of HFMD. The fitting value of SVR model is in good agreement with the actual value, which is valuable in predicting the incidence of HFMD in Sichuan Province.

Comparative Proteomic and Morpho-Physiological Analyses of Maize Wild-Type Vp16 and Mutant vp16 Germinating Seed Responses to PEG-Induced Drought Stress.

Drought stress is a major abiotic factor compromising plant cell physiological and molecular events, consequently limiting crop growth and productivity. Maize (Zea mays L.) is among the most drought-susceptible food crops. Therefore, understanding the mechanisms underlying drought-stress responses remains critical for crop improvement. To decipher the molecular mechanisms underpinning maize drought tolerance, here, we used a comparative morpho-physiological and proteomics analysis approach to monitor the changes in germinating seeds of two incongruent (drought-sensitive wild-type Vp16 and drought-tolerant mutant vp16) lines exposed to polyethylene-glycol-induced drought stress for seven days. Our physiological analysis showed that the tolerant line mutant vp16 exhibited better osmotic stress endurance owing to its improved reactive oxygen species scavenging competency and robust osmotic adjustment as a result of greater cell water retention and enhanced cell membrane stability. Proteomics analysis identified a total of 1200 proteins to be differentially accumulated under drought stress. These identified proteins were mainly involved in carbohydrate and energy metabolism, histone H2A-mediated epigenetic regulation, protein synthesis, signal transduction, redox homeostasis and stress-response processes; with carbon metabolism, pentose phosphate and glutathione metabolism pathways being prominent under stress conditions. Interestingly, significant congruence (R2 = 81.5%) between protein and transcript levels was observed by qRT-PCR validation experiments. Finally, we propose a hypothetical model for maize germinating-seed drought tolerance based on our key findings identified herein. Overall, our study offers insights into the overall mechanisms underpinning drought-stress tolerance and provides essential leads into further functional validation of the identified drought-responsive proteins in maize.

Mannose-Modificated Polyethylenimine: A Specific and Effective Antibacterial Agent against Escherichia coli.

Polyethylenimine (PEI) has antimicrobial activity against Gram-positive (Staphylococcus aureus, S. aureus) and Gram-negative (Escherichia coli, E. coli), bacteria but is highly cytotoxic, and the selective antimicrobial activity against S. aureus is obviously better than that against E. coli. To reduce the cytotoxicity and improve the antibacterial activity against E. coli, we modified PEI with d-mannose through nucleophilic addition between primary amine and aldehyde groups to get mannose-modified polyethylenimine copolymer particles (Man-PEI CPs). The use of mannose may provide good targeting ability toward E. coli pili. The antibacterial activity of Man-PEI CPs was investigated. Man-PEI CPs shows specific and very strong killing capability against E. coli at a concentration of 10 µg/mL, which is the highest antimicrobial efficiency compared to that of unmodified PEI (220 µg/mL). The antibacterial mechanism demonstrated that the enhancement in antibacterial activity is due to specific recognition of the mannose and destroying the cell wall of the bacteria by PEIs. Importantly, the Man-PEI CPs show less cytotoxicity and excellent biocompatibility. The results indicate that Man-PEI CPs have great potential as novel antimicrobial materials to prevent bacterial infections and provide specific applications for killing E. coli.

Children with Autism Spectrum Disorder scan own-race faces differently from other-race faces.

It has been well documented that people recognize and scan other-race faces differently from faces of their own race. The current study examined whether this cross-racial difference in face processing found in the typical population also exists in individuals with Autism Spectrum Disorder (ASD). Participants included 5- to 10-year-old children with ASD (n=29), typically developing (TD) children matched on chronological age (n=29), and TD children matched on nonverbal IQ (n=29). Children completed a face recognition task in which they were asked to memorize and recognize both own- and other-race faces while their eye movements were tracked. We found no recognition advantage for own-race faces relative to other-race faces in any of the three groups. However, eye-tracking results indicated that, similar to TD children, children with ASD exhibited a cross-racial face-scanning pattern: they looked at the eyes of other-race faces longer than at those of own-race faces, whereas they looked at the mouth of own-race faces longer than at that of other-race faces. The findings suggest that although children with ASD have difficulty with processing some aspects of faces, their ability to process face race information is relatively spared.

Phylogeographical analysis of a cold-temperate freshwater fish, the Amur sleeper (Perccottus glenii) in the Amur and Liaohe River basins of Northeast Asia.

The Amur sleeper Perccottus glenii (Perciformes, Gobioidei, Odontobutidae) is well known as an invasive fish in the river basins of Eastern and Central Europe, but its genetic background is unavailable across its native habitats in northeast Asia. In this study, we used the mitochondrial cytochrome b gene by sampling 19 populations of P. glenii across its native distributional areas of Liaohe and Amur River basins to explore its evolutionary history. Phylogenetic analyses identified three major clades within P. glenii, among which Clade A and Clade B were co-distributed in the Liaohe and Amur River basins, and Clade C was restricted to the latter. Molecular dating showed that the splits of Clades A, B and C have happened in the late Early-early Middle Pleistocene and the most recent common ancestors of these clades have been presented in the late Middle-early Late Pleistocene. The P. glenii showed very high levels of genetic structure among populations (ΦST = 0.801), probably due to the characters of its life histories with very limited dispersal ability. The admixture of different clades in some populations of P. glenii probably reflects historical secondary contact. These findings indicate that Pleistocene climatic oscillation and river capture were major determinants for genetic variations and evolutionary history of the P. glenii.

Anaerobic dynamic membrane bioreactor for the co-digestion of toilet blackwater and kitchen waste.

Anaerobic co-digestion using an anaerobic dynamic membrane bioreactor (AnDMBR) can separate the sludge retention time and hydraulic retention time, retaining the biomass for efficient degradation and the use of less expensive large pore-size membrane materials and more sustainable dynamic membranes (DMs). Therefore, anaerobic co-digestion of toilet blackwater (BW) and kitchen waste (KW) using an AnDMBR was hypothesized to increase the potential for co-digestion. Here, the efficiency and stability of AnDMBR in anaerobic co-digestion of toilet BW and KW were investigated. DM morphology and structural characteristics, filtration properties, and composition, as well as membrane contamination and membrane regeneration mechanisms, were investigated. Average daily biogas yields of the reactor in two membrane cycles before and after cleaning were 788.67 and 746.09 ml/g volatile solids, with average methane content of 66.64% and 67.27% and average COD removal efficiencies of 82.03% and 80.96%, respectively. The results showed that the bioreactor obtained good performance and stability. During the stabilization phase of the DM operation, the flux was maintained between 43.65 and 65.15 L/m2/h. DM was mainly composed of organic and inorganic elements. Off-line cleaning facilitated DM regulation and regeneration, restoring new Anaerobic morphology and structure. PRACTITIONER POINTS: High efficiency co-digestion of BW and KW was realized in the DMBR system. Average daily biogas yields before and after membrane cleaning were 788.67 and 746.09 ml/g volatile solids. Off-line cleaning facilitated DM regulation and regeneration as well as system stability. The flux was maintained between 43.65 and 65.15 L/m2/h during operation.

Chiral nanomaterials in tissue engineering.

Addressing significant medical challenges arising from tissue damage and organ failure, the field of tissue engineering has evolved to provide revolutionary approaches for regenerating functional tissues and organs. This involves employing various techniques, including the development and application of novel nanomaterials. Among them, chiral nanomaterials comprising non-superimposable nanostructures with their mirror images have recently emerged as innovative biomaterial candidates to guide tissue regeneration due to their unique characteristics. Chiral nanomaterials including chiral fibre supramolecular hydrogels, polymer-based chiral materials, self-assembling peptides, chiral-patterned surfaces, and the recently developed intrinsically chiroptical nanoparticles have demonstrated remarkable ability to regulate biological processes through routes such as enantioselective catalysis and enhanced antibacterial activity. Despite several recent reviews on chiral nanomaterials, limited attention has been given to the specific potential of these materials in facilitating tissue regeneration processes. Thus, this timely review aims to fill this gap by exploring the fundamental characteristics of chiral nanomaterials, including their chiroptical activities and analytical techniques. Also, the recent advancements in incorporating these materials in tissue engineering applications are highlighted. The review concludes by critically discussing the outlook of utilizing chiral nanomaterials in guiding future strategies for tissue engineering design.

Alginate nanogel-embedded liposomal drug carriers facilitate drug delivery efficiency in arthritis treatment.

Despite numerous advantages of liposomes in treating rheumatoid arthritis (RA), the in vivo stability remains a critical issue. Current strategies for improving liposomal stability often compromise their original properties. Herein, we designed an alginate nanogel-embedded liposome aiming at retaining those inherent advantages while enhancing their in vivo stability. The introduction of alginate network within the liposome core can provide mechanical support and controlled drug release without affecting the surface properties. Results showed the cross-linking of alginate network within the inner core of liposomes elevated the particle rigidity to 3 times, allowing for improved stability and decreased drug leakage. Moreover, this nanogel-embedded liposome with optimized elasticity obviously facilitated cellular uptake in inflammatory macrophages. When entering blood circulation, increased rigidity altered the composition of protein corona on the particle surface, resulting in 2-fold increase in circulation time and improved drug accumulation in arthritic joints. When anti-inflammatory chlorogenic acid (CA) was encapsulated into the nanogel network, this CA-loaded nanogel-embedded liposome significantly inhibited ROS production and inflammatory response, ultimately achieved superior therapeutic outcome in arthritic rats. Results demonstrated that this nanogel-embedded liposomes can essentially retain the inherent advantages and overcome the drawbacks of liposomes, thereby improving the drug delivery efficiency.

3D bioprinting approaches for spinal cord injury repair.

Regenerative healing of spinal cord injury (SCI) poses an ongoing medical challenge by causing persistent neurological impairment and a significant socioeconomic burden. The complexity of spinal cord tissue presents hurdles to successful regeneration following injury, due to the difficulty of forming a biomimetic structure that faithfully replicates native tissue using conventional tissue engineering scaffolds. 3D bioprinting is a rapidly evolving technology with unmatched potential to create 3D biological tissues with complicated and hierarchical structure and composition. With the addition of biological additives such as cells and biomolecules, 3D bioprinting can fabricate preclinical implants, tissue or organ-like constructs, andin vitromodels through precise control over the deposition of biomaterials and other building blocks. This review highlights the characteristics and advantages of 3D bioprinting for scaffold fabrication to enable SCI repair, including bottom-up manufacturing, mechanical customization, and spatial heterogeneity. This review also critically discusses the impact of various fabrication parameters on the efficacy of spinal cord repair using 3D bioprinted scaffolds, including the choice of printing method, scaffold shape, biomaterials, and biological supplements such as cells and growth factors. High-quality preclinical studies are required to accelerate the translation of 3D bioprinting into clinical practice for spinal cord repair. Meanwhile, other technological advances will continue to improve the regenerative capability of bioprinted scaffolds, such as the incorporation of nanoscale biological particles and the development of 4D printing.

Co-exposure of polycarbonate microplastics aggravated the toxic effects of imidacloprid on the liver and gut microbiota in mice.

The joint toxicity of microplastics (MPs) and pesticides may be different from MPs or pesticides individually, however, the information about the combined toxicity of MPs and pesticides is not well understood. Herein, we investigated the joint toxicity of polycarbonate (PC) MPs and imidacloprid (IMI) on mice. After orally exposure for 4 weeks, PC and/or IMI lowered the body weight gain of mice. Single exposure of IMI induced the tissue damage in liver by disturbing the redox homeostasis, and PC significantly aggravated the imbalance of redox homeostasis by facilitating the accumulation of IMI in liver. Additionally, compared to single exposure of PC or IMI, PC+IMI exposure caused more severe damage to the gut microstructure and microbial diversity. Several key metabolic pathways, especially the lipid metabolism, were significantly affected. Overall, these findings provide new insight into understanding the potential risk of co-exposure of microplastics and pesticides to animal and human health.

Catechol-Modified and MnO2-Nanozyme-Reinforced Hydrogel with Improved Antioxidant and Antibacterial Capacity for Periodontitis Treatment.

Periodontitis is an inflammatory disease characterized by tooth loss and alveolar bone resorption. Bacteria are the original cause of periodontitis, and excess reactive oxygen species (ROS) encourage and intensify inflammation. In this study, a mussel-inspired and MnO2 NPs-reinforced adhesive hydrogel capable of alleviating periodontitis with improved antibacterial and antioxidant abilities was developed. The hydrogel was created by combining polyvinyl alcohol (PVA), 3,4-dihydroxy-d-phenylalanine (DOPA), and MnO2 nanoparticles (NPs) (named PDMO hydrogel). The hydrogel was demonstrated to be able to scavenge various free radicals (including total ROS─O2•- and OH•) and relieve the hypoxia in an inflammatory microenvironment by scavenging excess ROS and generating O2 due to its superoxide dismutase (SOD)/catalase (CAT)-like activity. Besides, under 808 nm near-infrared (NIR) light, the photothermal performance of the PDMO hydrogel displayed favorable antibacterial and antibiofilm effects toward Escherichia coli, Staphylococcus aureus, and Porphyromonas gingivalis (up to nearly 100% antibacterial rate). Furthermore, the PDMO hydrogel exhibited favorable therapeutic efficacy in alleviating gingivitis in Sprague-Dawley rats, even comparable to or better than the commercial PERIO. In addition, in the periodontitis models, the PDMO2 group showed the height of the residual alveolar bone and the smallest shadow area of low density among other groups, indicating the positive role of the PDMO2 hydrogel in bone regeneration. Finally, the biosafety of the PDMO hydrogel was comprehensively investigated, and the hydrogel was demonstrated to have good biocompatibility. Therefore, the developed PDMO hydrogel provided an effective solution to resolve biofilm recolonization and oxidative stress in periodontitis and could be a superior candidate for local drug delivery system in the clinical management of periodontitis with great potential for future clinical translation.