A dynamically cross-linked catechol-grafted chitosan/gelatin hydrogel dressing synergised with photothermal therapy and baicalin reduces wound infection and accelerates wound healing.

Superior multifunctional hydrogel dressings are of considerable interest in wound healing. In clinical practice, it is useful to investigate hydrogel dressings that offer multifunctional benefits to expedite the process of wound healing. In this study, Catechol-grafted Chitosan, Gelatin, and Fe3+ as substrates to construct a hydrogel network. The network was dynamically cross-linked to form Ccg@Fe hydrogel substrate. Fe3O4 nanoparticles and baicalin, which possess antimicrobial and anti-inflammatory properties, were loaded onto the substrate to form a photothermal antibacterial composite hydrogel dressing (Ccg@Fe/Bai@Fe3O4 NPs). The Ccg@Fe hydrogel was characterised using Fourier transform infrared spectroscopy (FTIR) and Ultraviolet-visible spectrophotometry (UV-Vis). The morphological, mechanical, and adhesion properties of the hydrogel were determined using scanning electron microscopy (SEM) and a universal testing machine. The hydrogel's swelling, hemostasis, and self-healing properties were also evaluated. Additionally, the study determined the release rate of hydrogel-loaded antimicrobial and anti-inflammatory Baicalin (Ccg@Fe/Bai) and evaluated the photothermal antimicrobial properties of hydrogel-loaded Fe3O4 nanoparticles (Ccg@Fe/Bai@Fe3O4 NPs) through synergistic photothermal therapy (PTT). Histological staining of mice skin wound tissues using Masson and H&E revealed that the Ccg@Fe/Bai@Fe3O4 NPs hydrogel dressing demonstrated potential healing ability with the aid of PTT. The study suggests that this multifunctional hydrogel dressing has great potential for wound healing.

Construction of a Synthetic Microbial Community for Enzymatic Pretreatment of Wheat Straw for Biogas Production via Anaerobic Digestion.

Biological pretreatment is a viable method for enhancing biogas production from straw crops, with the improvement in lignocellulose degradation efficiency being a crucial factor in this process. Herein, a metagenomic approach was used to screen core microorganisms (Bacillus subtilis, Acinetobacter johnsonii, Trichoderma viride, and Aspergillus niger) possessing lignocellulose-degrading abilities among samples from three environments: pile retting wheat straw (WS), WS returned to soil, and forest soil. Subsequently, synthetic microbial communities were constructed for fermentation-enzyme production. The crude enzyme solution obtained was used to pretreat WS and was compared with two commercial enzymes. The synthetic microbial community enzyme-producing pretreatment (SMCEP) yielded the highest enzymatic digestion efficacy for WS, yielding cellulose, hemicellulose, and lignin degradation rates of 39.85, 36.99, and 19.21%, respectively. Furthermore, pretreatment of WS with an enzyme solution, followed by anaerobic digestion achieved satisfactory results. SMCEP displayed the highest cumulative biogas production at 801.16 mL/g TS, which was 38.79% higher than that observed for WS, 22.15% higher than that of solid-state commercial enzyme pretreatment and 25.41% higher than that of liquid commercial enzyme pretreatment. These results indicate that enzyme-pretreated WS can significantly enhance biogas production. This study represents a solution to the environmental burden and energy use of crop residues.

Association between predicted fat mass, predicted lean mass, predicted percent fat and type 2 diabetes mellitus in Japanese adults: a retrospective study.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is known to have obesity as a risk factor. Body mass index cannot distinguish between lean mass and fat mass. We aimed to examine the association between predicted fat mass, predicted lean mass, predicted percent fat and risk of T2DM in Japanese adults. We also explored whether these three new parameters could predict T2DM better than other obesity markers. METHODS: This present study is a secondary data analysis. The study enrolled 20,944 Japanese individuals who participated in the NAGALA medical assessment program between 2004 and 2015. 15,453 participants who are eligible and have complete information were included to our analysis. Through the use of Kaplan-Meier curve, restricted cubic spline and univariate and multivariate Cox regression analysis, the relationship between predicted fat mass, predicted lean mass, predicted percent fat and T2DM risk was examined. The area under the curve method was used to assess the differences between these markers of obesity. RESULTS: A total of 373 cases of T2DM occurred over a median time of 5.4 years. In the male group, we found a U-shaped connection between predicted fat mass, predicted lean mass, and T2DM onset (p value, non-linearity < 0.05). A linear relationship was found between predicted percent fat and T2DM onset. The linear relationship was also found in the female group for predicted fat mass, and predicted percent fat. And for women, predicted lean mass was not an independent predictor. The area under the curve (AUC) for predicted fat mass, predicted lean mass, predicted percent fat in men was 0.673 (95%CI: 0.639 ~ 0.707), 0.598 (95%CI: 0.561 ~ 0.635), 0.715 (95%CI: 0.684 ~ 0.745), respectively. In males, WHtR was the strongest predictor (AUC 0.7151, 95%CI: 0.684 ~ 0.746), followed by predicted percent fat (AUC 0.7150, 95%CI: 0.684 ~ 0.745). In the females, WHtR was also the strongest predictor (AUC 0.758, 95%CI: 0.703 ~ 0.813), followed by body mass index (AUC 0.757, 95%CI: 0.704 ~ 0.811) and predicted percent fat (AUC 0.742, 95%CI: 0.687 ~ 0.798). CONCLUSION: Predicted fat mass, predicted lean mass, predicted percent fat were strongly connected with an increased risk for developing T2DM in Japanese, particularly in males. WHtR and predicted percent fat had a slightly better discrimination than other common obesity indicators in males. In the females, predicted fat mass and predicted percent fat were associated with T2DM risk, WHtR and body mass index had the slightly higher predictive power.

Exercise intervention in middle-aged and elderly individuals with insomnia improves sleep and restores connectivity in the motor network.

Exercise is a potential treatment to improve sleep quality in middle-aged and elderly individuals. Understanding exercise-induced changes in functional plasticity of brain circuits that underlie improvements in sleep among middle-aged and older adults can inform treatment of sleep problems. The aim of the study is to identify the effects of a 12-week exercise program on sleep quality and brain functional connectivity in middle-aged and older adults with insomnia. The trial was registered with Chinese Clinical Trial Register (ChiCTR2000033652). We recruited 84 healthy sleepers and 85 individuals with insomnia. Participants with insomnia were assigned to receive either a 12-week exercise intervention or were placed in a 12-week waitlist control condition. Thirty-seven middle-aged and older adults in the exercise group and 30 in the waitlist group completed both baseline and week 12 assessments. We found that middle-aged and older adults with insomnia showed significantly worse sleep quality than healthy sleepers. At the brain circuit level, insomnia patients showed decreased connectivity in the widespread motor network. After exercise intervention, self-reported sleep was increased in the exercise group (P < 0.001) compared to that in the waitlist group. We also found increased functional connectivity of the motor network with the cerebellum in the exercise group (P < 0.001). Moreover, we observed significant correlations between improvement in subjective sleep indices and connectivity changes within the motor network. We highlight exercise-induced improvement in sleep quality and functional plasticity of the aging brain.

Solid-state fermentation of corn straw using synthetic microbiome to produce fermented feed: The feed quality and conversion mechanism.

Straw is a typical biomass resource which can be converted into high nutritional value feed via microbial fermentation. The degradation and conversion of straw using a synthetic microbial community (SMC-8) was functionally investigated to characterise its nitrogen conversion and carbon metabolism. Four species of bacteria were found to utilise >20 % of the inorganic nitrogen within 15 h, and the ratio of the diameter of fungal transparent circles (D) to the diameter of the colony (d) of the four fungal species was >1. Solid-state fermentation of corn straw increased the total amino acid (AA) content by 41.69 %. The absolute digestibility of fermented corn straw dry weight (DW) and true protein was 34.34 % and 45.29 %, respectively. Comprehensive analysis of functional proteins revealed that Aspergillus niger, Trichoderma viride, Cladosporium cladosporioides, Bacillus subtilis and Acinetobacter johnsonii produce a complex enzyme system during corn straw fermentation, which plays a key role in the degradation of lignocellulose. This study provided a new insight in utilizing corn straw.

Improving Microbial Cell Factory Performance by Engineering SAM Availability.

Methylated natural products are widely spread in nature. S-Adenosyl-l-methionine (SAM) is the secondary abundant cofactor and the primary methyl donor, which confer natural products with structural and functional diversification. The increasing demand for SAM-dependent natural products (SdNPs) has motivated the development of microbial cell factories (MCFs) for sustainable and efficient SdNP production. Insufficient and unsustainable SAM availability hinders the improvement of SdNP MCF performance. From the perspective of developing MCF, this review summarized recent understanding of de novo SAM biosynthesis and its regulatory mechanism. SAM is just the methyl mediator but not the original methyl source. Effective and sustainable methyl source supply is critical for efficient SdNP production. We compared and discussed the innate and relatively less explored alternative methyl sources and identified the one involving cheap one-carbon compound as more promising. The SAM biosynthesis is synergistically regulated on multilevels and is tightly connected with ATP and NAD(P)H pools. We also covered the recent advancement of metabolic engineering in improving intracellular SAM availability and SdNP production. Dynamic regulation is a promising strategy to achieve accurate and dynamic fine-tuning of intracellular SAM pool size. Finally, we discussed the design and engineering constraints underlying construction of SAM-responsive genetic circuits and envisioned their future applications in developing SdNP MCFs.

Integration of Single-Cell Transcriptomics Data Reveal Differences in Cell Composition and Communication in Acne.

Purpose: Acne is a kind of hair follicle sebaceous inflammatory disease, which has a high incidence rate among adolescents. Comparative data on cells which beneficial for precise treatment of acne patients. Patients and Methods: After integrating and removing the batch effect of single-cell transcriptomics data of acne patients and health skin, the dimensionality reduction clustering was performed and the change in characteristics of each cell group were analyzed. Further, cell communication differences between gender were analyzed by use Cellchat software. Results: 70,189 cells were analyzed, and 11 cell groups were identified. The proportion of basal cells and macrophages in skin of acne patients are relatively high than that of skin in healthy people. The results of cell communication showed that the communication intensity of acne patients was significantly higher than that of healthy skin, and the endothelial cells showed a strong ability to receive signals. From the perspective of gender differences, the proportion of macrophages in male patients were higher than that in female patients, and there were a large number of basal cells in the lesion area of female patients. There are also have some specific immune response ligand-receptor regulatory signals in male patients. Conclusion: There are significant differences in skin cell composition and cell communication patterns between acne patients and healthy people, especially reflected in gender differences. Basal cells, macrophages and endothelial cells can serve as key targets for acne treatment. The treatment methods for men and women should be more personalized.

Pretreatment of Luzhou distiller's grains for feed protein production using crude enzymes produced by a synthetic microbial consortium.

Chinese distillers' grains (CDGs) have low fermentation efficiency due to the presence of lignocellulosic components, such as rice husk. In this study, a microbial consortium synthesized was used based on the "functional complementarity" principle to produce lignocellulolytic crude enzyme. The crude enzyme was used to hydrolyze CDGs. After enzymatic hydrolysis, lignocellulose was damaged to varying degrees and the crystallinity decreased. Subsequently, the feed protein was produced using yeast through two pathways. The results showed that the crude enzyme produced by the microbial consortium (comprising Trichoderma reesei, Aspergillus niger, and Penicillium) exhibited excellent enzymatic efficiency, yielding 27.88%, 19.64%, and 10.88% of reducing sugar, cellulose, and hemicellulose. The true protein content of CDGs increased by 53.49% and 48.35% through the first and second pathways, respectively. Notably, the second pathway demonstrated higher economic benefits to produce feed protein. This study provides a pathway for high-quality utilization of CDGs.

Construction of a synthetic microbial community based on multiomics linkage technology and analysis of the mechanism of lignocellulose degradation.

The efficient degradation of lignocellulose is a bottleneck for its integrated utilization. This research performed species analysis and made functional predictions in various ecosystems using multiomics coupling to construct a core synthetic microbial community with efficient lignocellulose degradation function. The synthetic microbial community was employed to degrade corn straw via solid-state fermentation. The degradation mechanisms were resolved using proteomics. The optimum culture conditions included 10% inoculum level (w/v), 4% nitrogen source ratio and a fermentation time of 23 d. Under these conditions, the degradation rates of cellulose, hemicellulose, and lignin were 34.91%, 45.94%, and 23.34%, respectively. Proteomic analysis revealed that lignin 1,4-ß-xylanase, ß-xylosidase and endo-1,4-ß-xylanase were closely related to lignocellulose degradation. The metabolic pathways involved in lignocellulose degradation and the functional roles of eight strains were obtained. The synthesis of a microbial community via multiomics linkage technology can effectively decompose lignocellulose, which is useful for their further utilization.

Metagenomic next-generation sequencing assistance in identifying non-tuberculous mycobacterial infections.

Introduction: The advent of metagenomics next-generation sequencing (mNGS) has garnered attention as a novel method for detecting pathogenic infections, including Non-Tuberculous Mycobacterial (NTM) and tuberculosis (TB).However, the robustness and specificity of mNGS in NTM diagnostics have not been fully explored. Methods: In this retrospective study, we enrolled 27 patients with NTM genomic sequences via mNGS and conducted a comprehensive clinical evaluation. Results: Pulmonary NTM disease was the most commonly observed presentation, with a subset of patients also presenting with extrapulmonary NTM infections.mNGS analysis identified six distinct NTM species, primarily Mycobacteriumavium complex (MAC), followed by Mycobacterium intracellulare andMycobacterium abscessus. Conventional routine culture methods encountered challenges, resulting in negative results for all available 22 samples. Among the 10 patients who underwent quantitative polymerase chain reaction (qPCR) testing, five tested positive for NTM. Discussion: It is important to note that further species typing is necessary to determine the specific NTM type, as traditional pathogen detection methods serve as an initial step. In contrast, when supplemented with pathogen data, enables the identification of specific species, facilitating precise treatment decisions. In conclusion, mNGS demonstrates significant potential in aidingthe diagnosis of NTMdisease by rapidly detecting NTM pathogens and guiding treatment strategies. Its enhanced performance, faster turnaround time (TAT), and species identification capabilities make mNGS a promising tool for managing NTM infections.

Combined CNN and RNN Neural Networks for GPR Detection of Railway Subgrade Diseases.

Vehicle-mounted ground-penetrating radar (GPR) has been used to non-destructively inspect and evaluate railway subgrade conditions. However, existing GPR data processing and interpretation methods mostly rely on time-consuming manual interpretation, and limited studies have applied machine learning methods. GPR data are complex, high-dimensional, and redundant, in particular with non-negligible noises, for which traditional machine learning methods are not effective when applied to GPR data processing and interpretation. To solve this problem, deep learning is more suitable to process large amounts of training data, as well as to perform better data interpretation. In this study, we proposed a novel deep learning method to process GPR data, the CRNN network, which combines convolutional neural networks (CNN) and recurrent neural networks (RNN). The CNN processes raw GPR waveform data from signal channels, and the RNN processes features from multiple channels. The results show that the CRNN network achieves a higher precision at 83.4%, with a recall of 77.3%. Compared to the traditional machine learning method, the CRNN is 5.2 times faster and has a smaller size of 2.6 MB (traditional machine learning method: 104.0 MB). Our research output has demonstrated that the developed deep learning method improves the efficiency and accuracy of railway subgrade condition evaluation.

Role of circulating CD14++CD16+ monocytes and VEGF-B186 in formation of collateral circulation in patients with hyperacute AMI.

Introduction: Collateral formation is insufficient in some patients with acute myocardial infarction (AMI). Peripheral blood CD14++CD16+ monocytes (intermediate monocytes; IM) and vascular endothelial growth factors (VEGFs) are associated with formation of collateral circulation. Methods: We enrolled 49 patients with AMI who underwent emergency percutaneous transluminal coronary intervention (PCI) (Group A) and 27 patients underwent delayed PCI 1 week after AMI (Group B). The percentage of circulating IM and levels of VEGFs in circulation were determined on day 8th. Left ventricular ejection fraction (LVEF) was measured 3 months after AMI. Results: The peripheral levels of IM and serum VEGF levels on day 8th were significantly higher in patients with well-developed collateral circulation in Group A than those in Group B. The levels of circulating VEGFs in the collateral circulation (+) subgroup in Group B were lower than those in the collateral circulation (-) subgroup. Moreover, the serum VEGF-B186 levels positively correlated with IM. Conclusions: Hyperacute collateral formation in patients with AMI correlated with a higher percentage of CD14++CD16+ monocytes and VEGF-B186 levels in the circulation, which was associated with milder left ventricular remodeling. The regulation of CD14++CD16+ monocytes and VEGF-B may be critical to the formation of collateral circulation and to healing AMI.

Purification, Structural Analysis and Cardio-Protective Activity of Polysaccharides from Radix Astragali.

Two polysaccharides, named APS2-I and APS3-I, were purified from the water extract of Radix Astragali. The average molecular weight of APS2-I was 1.96 × 106 Da and composed of Man, Rha, GlcA, GalA, Glc, Gal, Xyl, and Ara in a molar ratio of 2.3:4.8:1.7:14.0:5.8:11.7:2.8:12.6, while the average molecular weight of APS3-I was 3.91 × 106 Da and composed of Rha, GalA, Glc, Gal, and Ara in a molar ratio of 0.8:2.3:0.8:2.3:4.1. Biological evaluation showed APS2-I and APS3-I had significant antioxidant activity and myocardial protection activity. Furthermore, total polysaccharide treatment could significantly enhance hemodynamic parameters and improve cardiac function in rat ischemia and reperfusion isolated heart models. These results provided important information for the clinical application of APS in the field of cardiovascular disease and implied that Astragalus polysaccharides (APS) could be considered as a reference for the quality control of Radix Astragali.

Consistency and adversarial semi-supervised learning for medical image segmentation.

Medical image segmentation based on deep learning has made enormous progress in recent years. However, the performance of existing methods generally heavily relies on a large amount of labeled data, which are commonly expensive and time-consuming to obtain. To settle above issue, in this paper, a novel semi-supervised medical image segmentation method is proposed, in which the adversarial training mechanism and the collaborative consistency learning strategy are introduced into the mean teacher model. With the adversarial training mechanism, the discriminator can generate confidence maps for unlabeled data, such that more reliable supervised information for the student network is exploited. In the process of adversarial training, we further propose a collaborative consistency learning strategy by which the auxiliary discriminator can assist the primary discriminator in achieving supervised information with higher quality. We extensively evaluate our method on three representative yet challenging medical image segmentation tasks: (1) skin lesion segmentation from dermoscopy images in the International Skin Imaging Collaboration (ISIC) 2017 dataset; (2) optic cup and optic disk (OC/OD) segmentation from fundus images in the Retinal Fundus Glaucoma Challenge (REFUGE) dataset; and (3) tumor segmentation from lower-grade glioma (LGG) tumors images. The experimental results validate the superiority and effectiveness of our proposal when compared with the state-of-the-art semi-supervised medical image segmentation methods.

2D SiP2/h-BN for a Gate-Controlled Phototransistor with Ultrahigh Sensitivity.

Two-dimensional (2D) materials are extremely attractive for the construction of highly sensitive photodetectors due to their unique electronic and optical properties. However, developing 2D photodetectors with ultrahigh sensitivity for extremely low-light-level detection is still a challenge owing to the limitation of high dark current and low detectivity. Herein, a gate-controlled phototransistor based on 2D SiP2/hexagonal boron nitride (h-BN) was rationally designed and demonstrated ultrahigh sensitivity for the first time. With a back-gate device geometry, the SiP2/h-BN phototransistor exhibits an ultrahigh detectivity of 3.4 × 1013 Jones, which is one of the highest values among 2D material-based photodetectors. In addition, the phototransistor also shows a gate tunable responsivity of ≤43.5 A/W at a gate voltage of 30 V due to the photogating effect. The ultrahigh sensitivity of the SiP2-based phototransistor is attributed to the extremely low dark current suppressed by the phototransistor configuration and the improved photocurrent by using h-BN as a substrate to reduce charge scattering. This work provides a facile strategy for improving the detectivity of photodetectors and validates the great potential of 2D SiP2 phototransistors for ultrasensitive optoelectronic applications.

Trace elements' deficiency in energy production through methanogenesis process: Focus on the characteristics of organic solid wastes.

Excessive or insufficient supplementation of trace elements (TEs) limits the progression of anaerobic digestion. The main reason for this is the lack of sufficient understanding of digestion substrate characteristics, which significantly affects the demand for TEs. In this review, the relationship between TEs requirements and substrate characteristics is discussed. We mainly focus on three aspects. 1) The basis for TE optimization and existing problems: The optimization of TEs often based on the total solids (TS) or volatile solids (VS) of substrates, does not fully consider substrate characteristics. 2) TE deficiency mechanisms for different types of substrates: nitrogen-rich, sulfur-rich, TE-poor, and easily hydrolyzed substrates are the four main types of substrates. The mechanisms underlying TEs deficiency in the different substrates are investigated. 3) Regulation of TE bioavailability: characteristics of substrates affect digestion parameters, which disturb the bioavailability TE. Therefore, methods for regulating bioavailability of TEs are discussed.

Fabrication of an exosome-loaded thermosensitive chitin-based hydrogel for dental pulp regeneration.

Injective thermosensitive hydrogels are considered promising scaffolds to trigger dental pulp regeneration in devitalized human teeth. In this study, we developed a hydroxypropyl chitin (HPCH)/chitin whisker (CW) thermosensitive hydrogel with enhanced mechanical properties and biological activities. Exosomes can serve as biomimetic tools for tissue engineering, but the rapid clearance of unconjugated exosomes in vivo limits their therapeutic effects. To address this challenge, exosomes were isolated from human pulp stem cells (hDPSCs) and directly embedded into the HPCH/CW pre-gel to form an exosome-loaded hydrogel (HPCH/CW/Exo). The exosome-loaded thermosensitive hydrogel can be easily injected into an irregular endodontic space and gelated in situ. In vitro cell experiments proved that the delivery of exosomes significantly improved the ability of hydrogels to promote odontogenesis and angiogenesis. Meanwhile, in vivo animal experiments revealed the formation of new dental pulp-like tissues in an implanted tooth root model. Therefore, the proposed hydrogel provides a great potential alternative to traditional root canal therapy in dental clinics.

Effects of NBP on postoperative cognitive dysfunction in rats via Nrf 2/ARE pathway.

OBJECTIVE: Postoperative cognitive dysfunction (POCD) is a common postoperative disease that threatens patients' quality of life, especially elderly patients. With the popularity of anesthesia/surgery, POCD has received more attention worldwide. The objective of this research is to evaluate 3-n-Butylphthalide (NBP)'s protective effect on postoperative cognitive function in rats and its related mechanisms. METHODS: Tibial fracture models of senile rats of POCD were established and divided into blank control group, solvent group, NBP group, Nrf 2 agonist group, and Nrf 2 inhibitor group. The changes in the cognitive abilities of rats were systematically evaluated by the Morris water maze test. After hematoxylin-eosin (HE) staining of the hippocampus, the morphological and structural changes of hippocampal neurons were observed by light microscopy. The expressions of apoptosis-related proteins were analyzed by immunohistochemistry and Western blot was used to detect the expressions of Nrf 2,HO-1,Mfn1,Mfn2,Drp1 proteins. Moreover, the changes in the morphology of mitochondria were observed by transmission electron microscopy. RESULTS: Through the water maze test, we observed that the incidence of postoperative cognitive impairment in the NBP, agonist, and inhibitor groups was substantially lower as compared to the blank control group and solvent group (P < 0.05). The expressions of Nrf 2, HO-1, Mfn1, Mfn2, and Drp1 proteins in the NBP group were upregulated in comparison to the blank control group and the solvent group. The expressions of related proteins in the inhibitor group were substantially lower in comparison to the NBP group. CONCLUSIONS: NBP can affect the postoperative cognitive function of rats by activating the Nrf 2/ARE signaling pathway.

Two microbial consortia obtained through purposive acclimatization as biological additives to relieve ammonia inhibition in anaerobic digestion.

Ammonia inhibition is a challenging issue in the anaerobic digestion (AD) of nitrogen-rich substrates and hinders the energy recovery from organic wastes. Bioaugmentation is promising strategy to stabilize AD systems with high ammonia concentration. The composition of microbial consortia often determines their effectiveness in bioaugmentation. Up to now, the effect of various microbial consortia as biological additives on the AD systems is not fully understood. In this study, two microbial consortia (syntrophic microbial consortium, MC, and hydrogenotrophic methanogen consortium, SS) were obtained through two domestication methods, and were applied in a nitrogen-rich AD system. The results showed that the MC and SS treatments could restore AD performance within 21 days and 83 days, respectively. The recovery of digestion performance depended on the methanogenic archaea Methanospirillum, Methanothermobacter, and Methanoculleus in the early and later stages. Analysis of the 13C isotope indicated that both MC and SS enhanced the hydrogenotrophic pathway. The KEGG analysis showed that the MC not only promoted the key enzyme genes in the hydrogenotrophic pathway but also had a positive effect on the related enzyme genes of propionate and butyrate degradation, which was affected by the abundant short-chain fatty acids degrading bacteria, such as Syntrophomonas, Syntrophobacter, and Tissierella in the MC. After recovery of digestion performance, there was no significant difference (p > 0.05) in methane yield between the MS and SS treatments. Therefore, the best intervention period for bioaugmentation is when the digestion performance of the AD system is unstable.

Extrafibrillarly Demineralized Dentin Matrix for Bone Regeneration.

Dentin is a natural extracellular matrix, but its availability in bone grafting and tissue engineering applications is underestimated due to a lack of proper treatment. In this study, the concept of extrafibrillar demineralization is introduced into the construction of dentin-derived biomaterials for bone regeneration for the first time. Calcium chelating agents with large molecular weights are used to selectively remove the extrafibrillar apatite minerals without disturbing the intrafibrillar minerals within dentin collagen, resulting in the formation of an extrafibrillarly demineralized dentin matrix (EDM). EDM with distinctive nanotopography and bone-like mechanical properties is found to significantly promote cell adhesion, migration, and osteogenic differentiation in vitro while enhancing in vivo bone healing of rat calvarial defects. The outstanding osteogenic performance of EDM is further confirmed to be related to the activation of the focal adhesion-cytoskeleton-nucleus mechanotransduction axis. Overall, this study shows that extrafibrillar demineralization of dentin has great potential to produce hierarchical collagen-based scaffolds for bone regeneration, and this facile top-down fabrication method brings about new ideas for the biomedical application of naturally derived bioactive materials.