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Wholly defined ex vivo expansion conditions for biliary tree stem cell (BTSC) organoids were established, consisting of a defined proliferative medium (DPM) used in combination with soft hyaluronan hydrogels. The DPM consisted of commercially available Kubota's Medium (KM), to which a set of small molecules, particular paracrine signals, and heparan sulfate (HS) were added. The small molecules used were DNA methyltransferase inhibitor (RG108), TGF- β Type I receptor inhibitor (A83-01), adenylate cyclase activator (Forskolin), and L-type Ca2+ channel agonist (Bay K8644). A key paracrine signal proved to be R-spondin 1 (RSPO1), a secreted protein that activates Wnts. Soluble hyaluronans, 0.05 % sodium hyaluronate, were used with DPM to expand monolayer cultures. Expansion of organoids was achieved by using DPM in combination with embedding organoids in Matrigel that was replaced with a defined thiol-hyaluronan triggered with PEGDA to form a hydrogel with a rheology [G*] of less than 100 Pa. The combination is called the BTSC-Expansion-Glycogel-System (BEX-gel system) for expanding BTSCs as a monolayer or as organoids. The BTSC organoids were expanded more than 3000-fold ex vivo in the BEX-gel system within 70 days while maintaining phenotypic traits indicative of stem/progenitors. Stem-cell-patch grafting of expanded BTSC organoids was performed on the livers of Fah-/- mice with tyrosinemia and resulted in the rescue of the mice and restoration of their normal liver functions. The BEX-gel system for BTSC organoid expansion provides a strategy to generate sufficient numbers of organoids for the therapeutic treatments of liver diseases.

Abstract Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by chronic inflammation and progressive fibrosis of the biliary tree. The majority of PSC patients suffer from concomitant inflammatory bowel disease (IBD), which has been suggested to promote disease development and progression. However, the molecular mechanisms by which intestinal inflammation may aggravate cholestatic liver disease remain incompletely understood. Here, we employ an IBD-PSC mouse model to investigate the impact of colitis on bile acid metabolism and cholestatic liver injury. Unexpectedly, intestinal inflammation and barrier impairment improve acute cholestatic liver injury and result in reduced liver fibrosis in a chronic colitis model. This phenotype is independent of colitis-induced alterations of microbial bile acid metabolism but mediated via hepatocellular NF-κB activation by lipopolysaccharide (LPS), which suppresses bile acid metabolism in-vitro and in-vivo. This study identifies a colitis-triggered protective circuit suppressing cholestatic liver disease and encourages multi-organ treatment strategies for PSC.

We propose highly efficient certificate-less (CL) protocols for the infrastructure used by authenticated key exchange (AKE). The construction is based on elliptic curves (EC) without pairing, which means it can be easily supported by most industrial cryptography libraries on constrained devices. Compared with other pairing-free CL solutions, the new CL-AKE protocol enjoys the least number of scalar multiplications over EC groups. We use a unified game-based model to formalize the security of each protocol, while most previous works only assess the security against a list of attacks, provide informal theorems without proper modeling, or use separate models for protocols in different stages. We also present an efficient integration of the core protocols into the TLS cipher suites and a stand-alone implementation for constrained devices. The performance is evaluated on constrained devices in real-world settings, which further confirms the efficiency of our proposal.

Abstract Background Ribosome stalling on ermBL at the tenth codon (Asp) and mRNA stabilization are believed to be mechanisms by which erythromycin (Ery) induces ermB expression. Expression of ermB is also induced by 16-membered ring macrolides (tylosin, josamycin and spiramycin), but the mechanism underlying this induction is unknown. Methods We introduced premature termination codons, alanine-scanning mutagenesis and amino acid mutations in ermBL and ermBL2. Results In this paper, we demonstrated that 16-membered ring macrolides can induce ermB expression but not ermC expression. The truncated mutants of the ermB-coding sequence indicate that the regulatory regions of ermB whose expression is induced by Ery and 16-membered ring macrolides are different. We proved that translation of the N-terminal region of ermBL is key for the induction of ermB expression by Ery, spiramycin (Spi) and tylosin (Tyl). We also demonstrated that ermBL2 is critical for the induction of ermB expression by erythromycin but not by 16-membered ring macrolides. Conclusions The translation of ermBL and the RNA sequence of the C-terminus of ermBL are critical for the induction of ermB expression by Spi and Tyl.

Objectives: To investigate the effect of aligner displacement on tooth movement and periodontal health to improve the efficiency of aligner treatment and explore the mechanism in vivo. Methods: A two-tooth site was established by a finite element (FE) model to virtually evaluate aligner staging. A randomized controlled experiment was conducted when the tooth sites in beagles were treated with fixed or aligner appliances with different movement and force, and tooth movement and internal structure were recorded during the alignment. After sacrificing five dogs, bone-periodontal ligament (PDL)-tooth specimens were removed and processed to conduct uniaxial compression and tensile tests as well as micro-CT imaging and histological analysis. Results: Three displacements of 0.25, 0.35 and 0.45 mm were obtained from FE analysis and applied in beagles. In general, aligners had poorer performance on movement compared to fixed systems in vivo, but the aligner with a staging of 0.35 mm had the highest accuracy (67.46%) (P

Doping engineering of metallic elements is of significant importance in photocatalysis, especially in the transition element range where metals possess empty ‘d’ orbitals that readily absorb electrons and increase carrier concentration. The doping of Mn ions produces dipole interactions that change the local structure of BiOCl, thus increasing the specific surface area of BiOCl and the number of mesoporous distributions, and providing a broader platform and richer surface active sites for catalytic reactions. The combination of Mn doping and metal Bi reduces the forbidden bandwidth of BiOCl, thereby increasing the absorption in the light region and strengthening the photocatalytic ability of BiOCl. The degradation of norfloxacin by Bi/Mn-doped BiOCl can reach 86.5% within 10 min. The synergistic effect of Mn doping and Bi metal can change the internal energy level and increase light absorption simultaneously. The photocatalytic system created by such a dual-technology combination has promising applications in environmental remediation.

Semiconductor photocatalysts are essential materials in the field of environmental remediation. Various photocatalysts have been developed to solve the contamination problem of norfloxacin in water pollution. Among them, a crucial ternary photocatalyst, BiOCl, has attracted extensive attention due to its unique layered structure. In this work, high-crystallinity BiOCl nanosheets were prepared using a one-step hydrothermal method. The obtained BiOCl nanosheets showed good photocatalytic degradation performance, and the degradation rate of highly toxic norfloxacin using BiOCl reached 84% within 180 min. The internal structure and surface chemical state of BiOCl were analyzed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman, Fourier transform infrared spectroscopy (FTIR), UV–visible diffuse reflectance (UV-vis), Brunauer–Emmett–Teller (BET), X-ray photoelectron spectra (XPS), and photoelectric techniques. The higher crystallinity of BiOCl closely aligned molecules with each other, which improved the separation efficiency of photogenerated charges and showed high degradation efficiency for norfloxacin antibiotics. Furthermore, the obtained BiOCl nanosheets possess decent photocatalytic stability and recyclability.

Photocatalytic elimination of antibiotics from the environment and drinking water is of great significance for human health. However, the efficiency of photoremoval of antibiotics such as tetracycline is severely limited by the prompt recombination of electron holes and slow charge migration efficacy. Fabrication of low-dimensional heterojunction composites is an efficient method for shortening charge carrier migration distance and enhancing charge transfer efficiency. Herein, 2D/2D mesoporous WO3/CeO2 laminated Z-scheme heterojunctions were successfully prepared using a two-step hydrothermal process. The mesoporous structure of the composites was proved by nitrogen sorption isotherms, in which sorption-desorption hysteresis was observed. The intimate contact and charge transfer mechanism between WO3 nanoplates and CeO2 nanosheets was investigated using high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy measurements, respectively. Photocatalytic tetracycline degradation efficiency was noticeably promoted by the formation of 2D/2D laminated heterojunctions. The improved photocatalytic activity could be attributed to the formation of Z-scheme laminated heterostructure and 2D morphology favoring spatial charge separation, confirmed by various characterizations. The optimized 5WO3/CeO2 (5 wt.% WO3) composites can degrade more than 99% of tetracycline in 80 min, achieving a peak TC photodegradation efficiency of 0.0482 min−1, which is approximately 3.4 times that of pristine CeO2. A Z-scheme mechanism is proposed for photocatalytic tetracycline by from WO3/CeO2 Z-scheme laminated heterojunctions based on the experimental results.

Successful regenerative medicine strategies of xenogeneic extracellular matrix need a synergistic balance among inflammation, fibrosis, and remodeling process. Adaptive macrophage subsets have been identified to modulate inflammation and orchestrate the repair of neighboring parenchymal tissues. This study fabricated PPARγ-primed CD68+CD206+ M2 phenotype (M2γ), and firstly verified their anti-inflammatory and tissue-regenerating roles in xenogeneic bioengineered organ regeneration. Our results showed that Th1-type CD3+CD8+ T cell response to xenogeneic-dentin matrix-based bioengineered root complex (xeno-complex) was significantly inhibited by M2γ macrophage in vitro. PPARγ activation also timely recruited CD68+CD206+ tissue macrophage polarization to xeno-complex in vivo. These subsets alleviated proinflammatory cytokines (TNF-α, IFN-γ) at the inflammation site and decreased CD3+CD8+ T lymphocytes in the periphery system. When translated to an orthotopic nonhuman primate model, PPARγ-primed M2 macrophages immunosuppressed IL-1β, IL-6, TNF-α, MMPs to enable xeno-complex to effectively escape immune-mediated rejection and initiate graft-host synergistic integrity. These collective activities promoted the differentiation of odontoblast-like and periodontal-like cells to guide pulp-dentin and cementum-PDLs-bone regeneration and rescued partially injured odontogenesis such as DSPP and periostin expression. Finally, the regenerated root showed structure-biomechanical and functional equivalency to the native tooth. The timely conversion of M1-to-M2 macrophage mainly orchestrated odontogenesis, fibrogenesis, and osteogenesis, which represents a potential modulator for intact parenchymal-stromal tissue regeneration of targeted organs.

Objective: To investigate the effects of Ginkgo biloba extract (GBE) on autophagy in human macrophages stimulated by cigarette smoke extract (CSE). Methods: The human monocyte cell line U937 was cultured in vitro, and phorbol ester (PMA) was added to the cell culture medium to induce differentiation into human macrophages. CSE was prepared by traditional methods for experiments. The cells were divided into four groups: the blank group, the CSE model group, the GBE + CSE group, and the rapamycin + CSE group. Immunofluorescence was used to identify human macrophages, transmission electron microscopy was used to observe the ultrastructure of human macrophages in each group, ELISA was used to measure the amount of IL-6 and IL-10 in the supernatant from each group of cells, the mRNA levels of p62, ATG5, ATG7, and Rab7 were measured by real-time qPCR, and the protein expression levels of p62, ATG5, ATG7, and Rab7 were measured by Western blotting. Results: U937 cells were successfully differentiated into human macrophages after induction with PMA. The CSE model group had many more autophagosomes than the blank group. Compared with the CSE model group, the GBE + CSE group and the rapamycin + CSE group had significantly more autophagolysosomal. Compared with the other groups, the CSE model group had a higher level of IL-6 but a lower level of IL-10 in the supernatant (p < 0.05). Compared with the blank group, the mRNA and protein expression levels of p62 in the CSE model group were significantly decreased, while the mRNA and protein expression levels of ATG5 and ATG7 were significantly increased in the CSE model group (p < 0.05). No difference was found in the mRNA and protein expression levels of Rab7 between the blank group and the CSE model group. Compared with the CSE model group, the IL-6 level in the GBE + CSE group and the rapamycin + CSE group cell culture supernatant decreased significantly, p62 mRNA and protein expression significantly decreased, while ATG5, ATG7, and Rab7 mRNA and protein expression levels were significantly increased (p < 0.05). Moreover, increased LC3-II/LC3-I ratio were also found in the GBE + CSE group and the rapamycin + CSE group compared with the CSE model group. Conclusions: GBE could promote the fusion of autophagosomes and lysosomes in human macrophages, enhance the autophagy function of human macrophages, and reduce the damaging effect of CSE on the autophagy function of macrophages.

Background & Aims: Acute liver failure (ALF) represents an unmet medical need in Western countries. Although the link between intestinal dysbiosis and chronic liver disease is well-established, there is little evidence for a functional role of gut-liver interaction during ALF. Here we hypothesized that intestinal dysbiosis may affect ALF. Methods: To test this hypothesis, we assessed the association of proton pump inhibitor (PPI) or long-term antibiotics (ABx) intake, which have both been linked to intestinal dysbiosis, and occurrence of ALF in the 500,000 participants of the UK BioBank population-based cohort. For functional studies, male Nlrp6-/- mice were used as a dysbiotic mouse model and injected with a sublethal dose of acetaminophen (APAP) or lipopolysaccharide (LPS) to induce ALF. Results: Multivariate Cox regression analyses revealed a significantly increased risk (odds ratio, 2.3–3) for developing ALF in UK BioBank participants with PPI or ABx. Similarly, dysbiotic Nlrp6-/- mice displayed exacerbated APAP- and LPS-induced liver injury, which was linked to significantly reduced gut and liver tissue microbiota diversity and correlated with increased intestinal permeability at baseline. Fecal microbiota transfer (FMT) from Nlrp6-/- mice into wild-type (WT) mice augmented liver injury on APAP treatment in recipient WT mice, resembling the inflammatory phenotype of Nlrp6-/- mice. Specifically, FMT skewed monocyte polarization in WT mice toward a Ly6Chi inflammatory phenotype, suggesting a critical function of these cells as sensors of gut-derived signals orchestrating the inflammatory response. Conclusions: Our data show an important yet unknown function of intestinal microbiota during ALF. Intestinal dysbiosis was transferrable to healthy WT mice via FMT and aggravated liver injury. Our study highlights intestinal microbiota as a targetable risk factor for ALF.

Titanium dioxide (TiO2) nanomaterials have been widely used in photocatalytic energy conversion and environmental remediation due to their advantages of low cost, chemical stability, and relatively high photo-activity. However, applications of TiO2 have been restricted in the ultraviolet range because of the wide band gap. Broadening the light absorption of TiO2 nanomaterials is an efficient way to improve the photocatalytic activity. Thus, black TiO2 with extended light response range in the visible light and even near infrared light has been extensively exploited as efficient photocatalysts in the last decade. This review represents an attempt to conclude the recent developments in black TiO2 nanomaterials synthesized by modified treatment, which presented different structure, morphological features, reduced band gap, and enhanced solar energy harvesting efficiency. Special emphasis has been given to the newly developed synthetic methods, porous black TiO2, and the approaches for further improving the photocatalytic activity of black TiO2. Various black TiO2, doped black TiO2, metal-loaded black TiO2 and black TiO2 heterojunction photocatalysts, and their photocatalytic applications and mechanisms in the field of energy and environment are summarized in this review, to provide useful insights and new ideas in the related field.

BackgroundFunctions of miRNAs involved in tumorigenesis are well reported, yet, their roles in normal cell lineage commitment remain ambiguous. Here, we investigated a specific “transcription factor (TF)-miRNA-Target” regulatory network during the lineage maturation of biliary tree stem cells (BTSCs) into adult hepatocytes (hAHeps).MethodBioinformatic analysis was conducted based on our RNA-seq and microRNA-seq datasets with four human hepatic-lineage cell lines, including hBTSCs, hepatic stem cells (hHpSCs), hepatoblasts (hHBs), and hAHeps. Short time-series expression miner (STEM) analysis was performed to reveal the time-dependent dynamically changed miRNAs and mRNAs. GO and KEGG analyses were applied to reveal the potential function of key miRNAs and mRNAs. Then, the miRDB, miRTarBase, TargetScan, miRWalk, and DIANA-microT-CDS databases were adopted to predict the potential targets of miRNAs while the TransmiR v2.0 database was used to obtain the experimentally supported TFs that regulate miRNAs. The TCGA, Kaplan–Meier Plotter, and human protein atlas (HPA) databases and more than 10 sequencing data, including bulk RNA-seq, microRNA-seq, and scRNA-seq data related to hepatic development or lineage reprogramming, were obtained from both our or other published studies for validation.ResultsSTEM analysis showed that during the maturation from hBTSCs to hAHeps, 52 miRNAs were downwardly expressed and 928 mRNA were upwardly expressed. Enrichment analyses revealed that those 52 miRNAs acted as pluripotency regulators for stem cells and participated in various novel signaling pathways, including PI3K/AKT, MAPK, and etc., while 928 mRNAs played important roles in liver-functional metabolism. With an extensive sorting of those key miRNAs and mRNAs based on the target prediction results, 23 genes were obtained which not only functioned as the targets of 17 miRNAs but were considered critical for the hepatic lineage commitment. A “TF-miRNA-Target” regulatory network for hepatic lineage commitment was therefore established and had been well validated by various datasets. The network revealed that the PI3K/AKT pathway was gradually suppressed during the hepatic commitment.ConclusionA total of 17 miRNAs act as suppressors during hepatic maturation mainly by regulating 23 targets and modulating the PI3K/AKT signaling pathway. The regulatory network uncovers possible signatures and guidelines enabling us to identify or obtain the functional hepatocytes for future study.

Ribosome stalling on ermBL at the tenth codon (Asp) is believed to be a major mechanism of ermB induction by erythromycin (Ery). In this study, we demonstrated that the mechanism of ermB induction by Ery depends not only on ermBL expression but also on previously unreported ermBL2 expression. Introducing premature termination codons in ermBL, we proved that translation of the N-terminal region of ermBL is the key component for ermB induced by Ery, whereas translation of the C-terminal region of ermBL did not affect Ery-induced ermB. Mutation of the tenth codon (Asp10) of ermBL with other amino acids showed that the degree of induction in vivo was not completely consistent with the data from the in vitro toe printing assay. Alanine-scanning mutagenesis of ermBL demonstrated that both N-terminal residues (R7-K11) and the latter part of ermBL (K20-K27) are critical for Ery induction of ermB. The frameshifting reporter plasmid showed that a new leader peptide, ermBL2, exists in the ermB regulatory region. Further, introducing premature termination mutation and alanine-scanning mutagenesis of ermBL2 demonstrated that the N-terminus of ermBL2 is essential for induction by Ery. Therefore, the detailed function of ermBL2 requires further study.