Magnetic Graphene Oxide Nanocomposites Boosts Craniomaxillofacial Bone Regeneration by Modulating circAars/miR-128-3p/SMAD5 Signaling Axis.

Background: The ability of nanomaterials to induce osteogenic differentiation is limited, which seriously imped the repair of craniomaxillofacial bone defect. Magnetic graphene oxide (MGO) nanocomposites with the excellent physicochemical properties have great potential in bone tissue engineering. In this study, we aim to explore the craniomaxillofacial bone defect repairment effect of MGO nanocomposites and its underlying mechanism. Methods: The biocompatibility of MGO nanocomposites was verified by CCK8, live/dead staining and cytoskeleton staining. The function of MGO nanocomposites induced osteogenic differentiation of BMSCs was investigated by ALP activity detection, mineralized nodules staining, detection of osteogenic genes and proteins, and immune-histochemical staining. BMSCs with or without MGO osteogenic differentiation induction were collected and subjected to high-throughput circular ribonucleic acids (circRNAs) sequencing, and then crucial circRNA circAars was screened and identified. Bioinformatics analysis, Dual-luciferase reporter assay, RNA binding protein immunoprecipitation (RIP), fluorescence in situ hybridization (FISH) and osteogenic-related examinations were used to further explore the ability of circAars to participate in MGO nanocomposites regulation of osteogenic differentiation of BMSCs and its potential mechanism. Furthermore, critical-sized calvarial defects were constructed and were performed to verify the osteogenic differentiation induction effects and its potential mechanism induced by MGO nanocomposites. Results: We verify the good biocompatibility and osteogenic differentiation improvement effects of BMSCs mediated by MGO nanocomposites. Furthermore, a new circRNA-circAars, we find and identify, is obviously upregulated in BMSCs mediated by MGO nanocomposites. Silencing circAars could significantly decrease the osteogenic ability of MGO nanocomposites. The underlying mechanism involved circAars sponging miR-128-3p to regulate the expression of SMAD5, which played an important role in the repair craniomaxillofacial bone defects mediated by MGO nanocomposites. Conclusion: We found that MGO nanocomposites regulated osteogenic differentiation of BMSCs via the circAars/miR-128-3p/SMAD5 pathway, which provided a feasible and effective strategy for the treatment of craniomaxillofacial bone defects.

Single missing molar with wide mesiodistal length restored using a single or double implant-supported crown: A self-controlled case report and 3D finite element analysis.

PURPOSE: Based on a self-controlled case, this study evaluated the finite element analysis (FEA) results of a single missing molar with wide mesiodistal length (MDL) restored by a single or double implant-supported crown. METHODS: A case of a missing bilateral mandibular first molar with wide MDL was restored using a single or double implant-supported crown. The implant survival and peri-implant bone were compared. FEA was conducted in coordination with the case using eight models with different MDLs (12, 13, 14, and 15 mm). Von Mises stress was calculated in the FEA to evaluate the biomechanical responses of the implants under increasing vertical and lateral loading, including the stress values of the implant, abutment, screw, crown, and cortical bone. RESULTS: The restorations on the left and right sides supported by double implants have been used for 6 and 12 years, respectively, and so far have shown excellent osseointegration radiographically.The von Mises stress calculated in the FEA showed that when the MDL was >14 mm, both the bone and prosthetic components bore more stress in the single implant-supported strategy. The strength was 188.62-201.37 MPa and 201.85-215.9 MPa when the MDL was 14 mm and 15 mm, respectively, which significantly exceeded the allowable yield stress (180 MPa). CONCLUSIONS: Compared with the single implant-supported crown, the double implant-supported crown reduced peri-implant bone stress and produced a more appropriate stress transfer model at the implant-bone interface when the MDL of the single missing molar was ≥14 mm.

Unconventional Dental Implant Placement Through an Impacted Maxillary Central Incisor in Stable Contact With Enamel and Dentin: A Case Report.

When edentulism is accompanied by an impacted tooth, conventional treatment usually involves traumatic tooth extraction, which would inevitably destroy the surrounding alveolar bone and cause unfavorable esthetics, especially for anterior teeth. Recently, implant placement through the impacted tooth or residual root has been proposed as an alternative to invasive extraction. A particular type of integration has been observed between dentin/cementum and titanium implant, while enamel-implant contact has not been reported. In this article, an implant was placed through the impacted maxillary central incisor, thereby avoiding an invasive extraction surgery. The buccal section of the tooth, including crown enamel, was retained in situ for buccal alveolar ridge preservation. The follow-up results were satisfactory, and a stable enamel-implant contact was observed. Combining with previous similar studies, this technique opens intriguing possibilities and brings fresh insight for the concept of dentointegration. More histological and clinical studies with long-term follow-up are warranted before endorsing this technique in routine application.

Calcitonin gene-related peptide-modulated macrophage phenotypic alteration regulates angiogenesis in early bone healing.

OBJECTIVES: This study aimed to investigate the effect of calcitonin gene-related peptide (CGRP) on the temporal alteration of macrophage phenotypes and macrophage-regulated angiogenesis duringearlybonehealing and preliminarily elucidate the mechanism. METHODS: In vivo, the rat mandibular defect models were established with inferior alveolar nerve transection (IANT) or CGRP receptor antagonist injection. Radiographicandhistologic assessments for osteogenesis, angiogenesis, and macrophage phenotypic alteration within bone defects were performed. In vitro, the effect and mechanism of CGRP on macrophage polarization and phenotypic alteration were analyzed. Then the conditioned medium (CM) from CGRP-treated M1 or M2 macrophages was used to culture human umbilical vein endothelial cells (HUVECs), and the CGRP's effect on macrophage-regulated angiogenesis was detected. RESULTS: Comparable changes following IANT and CGRP blockade within bone defects were observed, including the suppression of early osteogenesis and angiogenesis, the prolonged M1 macrophage infiltration and the prohibited transition toward M2 macrophages around vascular endothelium. In vitro experiments showed that CGRP promoted M2 macrophage polarization while upregulating the expression of interleukin 6 (IL-6), a major cytokine that facilitates the transition from M1 to M2-dominant stage, in M1 macrophages via the activation of Yes-associated protein 1. Moreover, CGRP-treated macrophage-CM showed an anabolic effect on HUVECs angiogenesis compared with macrophage-CM and might prevail over the direct effect of CGRP on HUVECs. CONCLUSIONS: Collectively, our results reveal the effect of CGRP on M1 to M2 macrophage phenotypic alteration possibly via upregulating IL-6 in M1 macrophages, and demonstrate the macrophage-regulated pro-angiogenic potential of CGRP in early bone healing.

Mettl3­mediated m6A RNA methylation regulates osteolysis induced by titanium particles.

Peri­prosthetic osteolysis (PPO) induced by wear particles is considered the primary cause of titanium prosthesis failure and revision surgery. The specific molecular mechanisms involve titanium particles inducing multiple intracellular pathways, which impact disease prevention and the targeted therapy of PPO. Notably, N6­methyladenosine (m6A) serves critical roles in epigenetic regulation, particularly in bone metabolism and inflammatory responses. Thus, the present study aimed to determine the role of RNA methylation in titanium particle­induced osteolysis. Results of reverse transcription­quantitative PCR (RT­qPCR), western blotting, ELISA and RNA dot blot assays revealed that titanium particles induced osteogenic inhibition and proinflammatory responses, accompanied by the reduced expression of methyltransferase­like (Mettl) 3, a key component of m6A methyltransferase. Specific lentiviruses vectors were employed for Mettl3 knockdown and overexpression experiments. RT­qPCR, western blotting and ELISA revealed that the knockdown of Mettl3 induced osteogenic inhibition and proinflammatory responses comparable with that induced by titanium particle, while Mettl3 overexpression attenuated titanium particle­induced cellular reactions. Methylated RNA immunoprecipitation­qPCR results revealed that titanium particles mediated the methylation of two inhibitory molecules, namely Smad7 and SMAD specific E3 ubiquitin protein ligase 1, via Mettl3 in bone morphogenetic protein signaling, leading to osteogenic inhibition. Furthermore, titanium particles induced activation of the nucleotide binding oligomerization domain 1 signaling pathway through methylation regulation, and the subsequent activation of the MAPK and NF­κB pathways. Collectively, the results of the present study indicated that titanium particles utilized Mettl3 as an upstream regulatory molecule to induce osteogenic inhibition and inflammatory responses. Thus, the present study may provide novel insights into potential therapeutic targets for aseptic loosening in titanium prostheses.

Effect of artificial landmarks of the prefabricated auxiliary devices located at different arch positions on the accuracy of complete-arch edentulous digital implant scanning: An in-vitro study.

OBJECTIVES: To examine the effect of artificial landmarks of prefabricated auxiliary devices (PAD) located at different arch positions on the accuracy of complete-arch edentulous digital implant scanning. METHODS: A reference model containing four analogs and PAD were fabricated by a 3D printer (AccuFab-C1s, 3DShining). 10 digital scans were performed using an intraoral scanner (Aoralscan 3, 3DShining), sv 1.0.0.3115, with artificial landmarks located at different arch positions: group I, without any artificial landmarks; group II, with artificial landmarks at the anterior region; group III, with artificial landmarks at the posterior region. group IV: with artificial landmarks at both anterior and posterior regions. For group V: Conventional open-tray splinted impressions. The reference file and conventional stone casts were digitalized by using a dental laboratory scanner. The related files were imported into inspection software for trueness and precision assessment. Statistical analysis was performed with One-way ANOVA and Kruskal-Wallis test. The level of significance was set at α=0.05. RESULTS: For the global accuracy assessment, significantly higher global trueness was seen in group II (p < 0.01), III (p < 0.001), IV (p < 0.001) and V (p < 0.001) than group I. Significantly higher global precision was seen in group III (p < 0.001), IV (p < 0.001) and V (p < 0.001) than group I. For the local accuracy assessment, the PAD primarily improved accuracy on the linear deviations. CONCLUSIONS: Artificial landmarks of PAD at different arch positions significantly influenced the scanning accuracy. Applying the PAD in group IV could achieve comparable outcomes to conventional open-tray splinted impressions. Artificial landmarks on the posterior region may be more pivotal than those on the anterior region. CLINICAL SIGNIFICANCE: Group IV could achieve comparable accuracy to conventional open-tray splinted impressions.

Effect of prefabricated auxiliary devices and scanning patterns on the accuracy of complete-arch implant digital impressions.

OBJECTIVES: This study aimed to evaluate the impact of prefabricated auxiliary devices (PAD) and scanning patterns on the accuracy of complete-arch implant digital impressions. METHODS: An edentulous maxillary model was inserted with four parallel implant analogs and four PAD. The model was scanned with D2000 dental laboratory scanner as the reference scans. Test scans were obtained by 8 different scanning patterns (SP), which including SPA, SPB, SPC, SPD, SPE, SPF, SPG and SPH, with (test group) or without (control group) using the PAD by an intraoral scanner (Aoralscan 3, 3DShining). SPA was the scanning pattern recommended by the manufacturer. Each scanning time was recorded. The related files were imported into inspection software for assessment. Aligned Ranks Transformation ANOVA, Kruskal-Wallis and Mann-Whitney tests were used to evaluate the values. The level of significance was set at α = 0.05. RESULTS: The scanning patterns significantly influenced the linear accuracy in the test group and the scanning time for both groups. Lower linear trueness in the test group was found in SPF (p<0.05) and SPG (p<0.05). Longer scanning time was found in SPB and SPG for both groups. The test group demonstrated linear accuracy enhancement in all the scanning patterns; angular trueness enhancement was seen in SPA (p<0.05), SPC (p<0.01) and SPH (p<0.01). Significant longer scanning time was found in SPB (p<0.05), SPF (p<0.05), SPG (p<0.05) and SPH (p<0.05) when using PAD. CONCLUSION: The scanning patterns impact the accuracy differently depending on the PAD's existence. The scanning time can be significantly influenced by the scanning patterns and the PAD. CLINICAL SIGNIFICANCE: In daily clinical practice, selecting a suitable scanning pattern is significant in achieving accurate digital impressions. The PAD demonstrated effective linear accuracy enhancement in all the scanning patterns tested.

Magnetic graphene oxide nanocomposites induce cytotoxicity in ADSCs via GPX4 regulating ferroptosis.

Magnetic graphene oxide nanocomposites (MGO NPs) have been widely studied in biomedical applications. However, their cytotoxicity and underlying mechanisms remain unclear. In this study, the biosafety of MGO NPs was investigated, and the mechanism involved in ferroptosis was further explored. MGO can produce cytotoxicity in ADSCs, which is dependent on their concentration. Ferroptosis was involved in MGO NP-induced ADSC survival inhibition by increasing total ROS and lipid ROS accumulation as well as regulating the expression levels of ferroptosis-related genes and proteins. GPX4 played a critical role in the MGO NP-induced ADSC ferroptosis process, and overexpressing GPX4 suppressed ferroptosis to increase cell survival. This study provides a theoretical basis for the biosafety management of MGO NPs used in the field of biomedical treatment.

Screening and evaluation of skin potential probiotic from high-altitude Tibetans to repair ultraviolet radiation damage.

Human skin microbes play critical roles in skin health and diseases. Microbes colonizing on the skin of Tibetans living in the high-altitude area for generations may have a stronger ability to resist the harsh environment, such as high ultraviolet radiation (UV). Isolation of a potential probiotic from Tibetans skin is beneficial for resistance of skin disease for humans in the world. In this study, the signature microbiota for Tibetan skin were characterized compared to low-altitude humans. Next, using culture-omics, 118 species were isolated. The culturability of high-altitude of Tibetan skin microbiome reached approximate 66.8%. Next, we found that one strain, Pantoea eucrina, had the greatest ability to repair UV damage to the skin as the lowest pathological score was observed in this group. Interestingly, another animal trial found this bacterium resisted UV rather than its metabolites. Using whole genome sequencing, this strain P. eucrina KBFS172 was confirmed, and its functions were annotated. It might involve in the metabolic pathway of carotenoid biosynthesis with anti-oxidative stress properties, which plays critical roles in UV-damage repair. In conclusion, we characterized the signature microbes of skin in high-altitude Tibetans, isolated a skin bacterium of Pantoea eucrina KBFS172 which could repair UV damage via involving the metabolic pathway of carotenoid biosynthesis. Our results provide a new potential skin probiotic for skin disease prevention or sunburn.

The spatial dissimilarities and connections of the microbiota in the upper and lower respiratory tract of beef cattle.

Bovine respiratory disease (BRD) causes morbidity and mortality in cattle. The critical roles of the respiratory microbiota in BRD have been widely studied. The nasopharynx was the most popular sampling niche for BRD pathogen studies. The oral cavity and other niches within the respiratory tract, such as nostrils and lung, are less assessed. In this study, oropharyngeal swabs (OS), nasal swabs (NS), nasopharyngeal swabs (NP), and bronchoalveolar lavage (BAL) were collected from calves located in four countries and analyzed for investigation of the dissimilarities and connections of the respiratory microbiota. The results showed that the microbial diversity, structure, and composition in the upper and lower respiratory tract in beef cattle from China, the USA, Canada, and Italy were significantly different. The microbial taxa for each sampling niche were specific and associated with their local physiology and geography. The signature microbiota for OS, NS, NP, and BAL were identified using the LEfSe algorithm. Although the spatial dissimilarities among the respiratory niches existed, the microbial connections were observed in beef cattle regardless of geography. Notably, the nostril and nasopharynx had more similar microbiomes compared to lung communities. The major bacterial immigration patterns in the bovine respiratory tract were estimated and some of them were associated with geography. In addition, the contribution of oral microbiota to the nasal and lung ecosystems was confirmed. Lastly, microbial interactions were characterized to reveal the correlation between the commercial microbiota and BRD-associated pathogens. In conclusion, shared airway microbiota among niches and geography provides the possibility to investigate the common knowledge for bovine respiratory health and diseases. In spite of the dissimilarities of the respiratory microbiota in cattle, the spatial connections among these sampling niches not only allow us to deeply understand the airway ecosystem but also benefit the research and development of probiotics for BRD.

Osseointegration of functionally graded Ti6Al4V porous implants: Histology of the pore network.

The additive manufacturing of titanium into porous geometries offers a means to generate low-stiffness endosseous implants with a greater surface area available for osseointegration. In this work, selective laser melting was used to produce gyroid-based scaffolds with a uniform pore size of 300 µm or functionally graded pore size from 600 µm to 300 µm. Initial in vitro assessment with Saos-2 cells showed favourable cell proliferation at pore sizes of 300 and 600 µm. Following implantation into rabbit tibiae, early histological observations at four weeks indicated some residual inflammation alongside neovessel infiltration into the scaffold interior and some early apposition of mineralized bone tissue. At twelve weeks, both scaffolds were filled with a mixture of adipocyte-rich marrow, micro-capillaries, and mineralized bone tissue. X-ray microcomputed tomography showed a higher bone volume fraction (BV/TV) and percentage of bone-implant contact (BIC) in the implants with 300 µm pores than in the functionally graded specimens. In functionally graded specimens, localized BV/TV measurement was observed to be higher in the innermost region containing smaller pores (estimated at 300-400 µm) than in larger pores at the implant exterior. The unit cell topology of the porous implant was also observed to guide the direction of bone ingrowth by conducting along the implant struts. These results suggest that in vivo experimentation is necessary alongside parametric optimization of functionally graded porous implants to predict short-term and long-term bone apposition.

ATG7-mediated autophagy protects human gingival myofibroblasts from irradiation-induced apoptosis.

BACKGROUND: Apoptosis resistance of myofibroblasts is critical in pathology of irradiation-induced fibrosis and osteoradionecrosis of the jaw (ORNJ). However, molecular mechanism of apoptosis resistance induced by irradiation in oral myofibroblasts remains largely obscure. METHODS: Matched ORNJ fibroblasts and normal fibroblasts pairs from gingival were primarily cultured, and myofibroblast markers of α-SMA and FAP were evaluated by qRT-PCR and western blot. CCK8 assay and flow cytometric analysis were performed to investigate the cell viability and apoptosis under irradiation treatment. Autophagy-related protein LC3 and ATG7, and punctate distribution of LC3 localization were further detected. After inhibition of autophagy with inhibitor CQ and 3-MA, as well as transfected ATG7-siRNA, cell viability and apoptosis of ORNJ and normal fibroblasts were further assessed. RESULTS: Compared with normal fibroblasts, ORNJ fibroblasts exhibited significantly higher α-SMA and FAP expression, increased cell, viability and decreased apoptosis under irradiation treatment. LC3-II and ATG7 were up-regulated in ORNJ fibroblasts with irradiation stimulation. After inhibition of irradiation-induced autophagic flux with lysosome inhibitor CQ, LC3-II protein was accumulated and punctate distribution of LC3 localization was increased in ORNJ fibroblasts. Moreover, autophagy inhibitor CQ and 3-MA enhanced the irradiation-induced apoptosis but inhibited viability of ORNJ fibroblasts. Silencing ATG7 with siRNA could obviously weaken irradiation-induced LC3-II expression, and promoted irradiation-induced apoptosis of ORNJ fibroblasts. After knockdown of ATG7, finally, p-AKT(Ser473) and p-mTOR(Ser2448) levels of ORNJ fibroblasts were significantly increased under irradiation. CONCLUSION: Compared with normal fibroblasts, human gingival myofibroblasts are resistant to irradiation-induced apoptosis via autophagy activation. Silencing ATG7 may evidently inhibit activation of autophagy, and promote apoptosis of gingival myofibroblasts via Akt/mTOR pathway.

The role of gut archaea in the pig gut microbiome: a mini-review.

The gastrointestinal microbiota of swine harbors an essential but often overlooked component: the gut archaea. These enigmatic microorganisms play pivotal roles in swine growth, health, and yield quality. Recent insights indicate that the diversity of gut archaea is influenced by various factors including breed, age, and diet. Such factors orchestrate the metabolic interactions within the porcine gastrointestinal environment. Through symbiotic relationships with bacteria, these archaea modulate the host's energy metabolism and digestive processes. Contemporary research elucidates a strong association between the abundance of these archaea and economically significant traits in swine. This review elucidates the multifaceted roles of gut archaea in swine and underscores the imperative for strategic interventions to modulate their population and functionality. By exploring the probiotic potential of gut archaea, we envisage novel avenues to enhance swine growth, health, and product excellence. By spotlighting this crucial, yet under-investigated, facet of the swine gut microbiome, we aim to galvanize further scientific exploration into harnessing their myriad benefits.

Effect of novel prefabricated auxiliary devices attaching to scan bodies on the accuracy of intraoral scanning of complete-arch with multiple implants: An in-vitro study.

OBJECTIVES: To examine the effect of novel prefabricated auxiliary devices with different geometric features called Scan Body Clasp (SBC) at different levels on the accuracy of intraoral scanning of complete-arch with multiple implants. METHODS: An edentulous maxilla 4-implant model and SBCs with different geometric features (flat or curved) were fabricated by a 3D printer (AccuFab-C1s, 3DShining, Hangzhou, China). Test scans were performed using an intraoral scanner (Aoralscan 3, 3DShining, Hangzhou, China) software version 1.0.0.3104 under different scenarios: group A (CO), without any SBCs; group B&C (LC&HC), with curved SBCs adjacent to and away from the mucosa; group D&E (LF&HF), with flat SBCs adjacent to and away from the mucosa. 20 scans were done for each group (CO, LC, HC, LF and HF). Reference Scans were obtained by digitizing the model in group A using a dental laboratory scanner (D2000, 3Shape, Copenhagen, Denmark). The related files were imported into inspection software for trueness and precision assessment. Statistical analysis was performed with One-way ANOVA, Independent-Sample T test for trueness values. Kruskal-Wallis test and Mann-Whitney test were used to assess the precision values. The level of significance was set at α=0.05. RESULTS: Groups with SBCs demonstrated trueness enhancement, among which LF revealed the best trueness. Significant differences were also found between LF and HC (p < .01), LF and HF (p < .001), LC and HF (p < .01). LF and HF showed precision enhancement. The best precision was LF, which was found to be more precise than LC (p < .001) and HC (p < .001). HF was more precise than LC (p < .001) and HC (p < .001). CONCLUSIONS: Attaching the scan bodies with SBCs at different levels significantly influenced the scanning accuracy. The SBCs near the mucosa result in superior trueness, while the flat morphology benefits the precision. CLINICAL SIGNIFICANCE: The results demonstrated the feasibility of the SBCs in enhancing intraoral complete-arch implant scanning accuracy. Among the configurations tested in the present study, low-level and flat surfaces of the artificial landmarks may be the potential pivotal elements to optimizing long-span scanning accuracy.

Changes of dental anxiety, aesthetic perception and oral health-related quality of life related to influencing factors of patients' demographics after anterior implant treatment: a prospective study.

BACKGROUND: Accumulating evidence has revealed the effects of anterior implant procedures on dental anxiety (DA), aesthetic perception and oral health-related quality of life (OHRQoL). However, few reported the changes and influencing factors of the above outcomes before and after anterior implant treatment. This study was to evaluate the changes of DA, aesthetic perception and OHRQoL related to influencing factors of patients' demographics after anterior implant treatment. METHODS: Thirty-nine patients satisfying the inclusion criteria were prospectively recruited before surgery. The subjects completed the Modified Dental Anxiety Scale (MDAS), the Orofacial Esthetic Scale (OSE) and the Oral Health Impact Profile-14 (OHIP-14), before implant surgery and after definitive prosthesis placement. Mann-Whitney U test and Kruskal-Wallis test by Bonferroni correction were applied for the data analysis and the influencing factors evaluation (p < 0.05). RESULTS: Overall, 39 patients (mean age of 44.9 ± 12.0) completed the three scales. After anterior implant treatment, MDAS was not significantly changed (p > 0.05). The overall OSE (p < 0.001) and OHIP-14 (p < 0.05) were significantly improved. Females showed more improvement of overall OHIP score than males after anterior implant treatment (p < 0.05). CONCLUSIONS: Anterior implant procedures did not change the level of patient's DA, while aesthetic perception and OHRQoL were enhanced. Only gender difference of overall OHIP change was found in our study. Thus, more related influencing factors with larger sample and long-term effective follow-up are needed. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05424458. Registered 13 June 2022-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT05424458 .

The unique gut microbiome of giant pandas involved in protein metabolism contributes to the host's dietary adaption to bamboo.

BACKGROUND: The gut microbiota of the giant panda (Ailuropoda melanoleuca), a global symbol of conservation, are believed to be involved in the host's dietary switch to a fibrous bamboo diet. However, their exact roles are still largely unknown. RESULTS: In this study, we first comprehensively analyzed a large number of gut metagenomes giant pandas (n = 322), including 98 pandas sequenced in this study with deep sequencing (Illumina) and third-generation sequencing (nanopore). We reconstructed 408 metagenome-assembled genomes (MAGs), and 148 of which (36.27%) were near complete. The most abundant MAG was classified as Streptococcus alactolyticus. A pairwise comparison of the metagenomes and meta-transcriptomes in 14 feces revealed genes involved in carbohydrate metabolism were lower, but those involved in protein metabolism were greater in abundance and expression in giant pandas compared to those in herbivores and omnivores. Of note, S. alactolyticus was positively correlated to the KEGG modules of essential amino-acid biosynthesis. After being isolated from pandas and gavaged to mice, S. alactolyticus significantly increased the relative abundance of essential amino acids in mice jejunum. CONCLUSIONS: The study highlights the unique protein metabolic profiles in the giant panda's gut microbiome. The findings suggest that S. alactolyticus is an important player in the gut microbiota that contributes to the giant panda's dietary adaptation by more involvement in protein rather than carbohydrate metabolism. Video Abstract.

Accuracy of single-implant digital impression with various scanbody exposure levels at anterior and posterior regions.

OBJECTIVES: This in vitro study aimed to evaluate the effect of the exposure heights of the scanbody on the accuracy of digital implant impressions at different positions. METHODS: Four maxillary master models with one analog at the anterior and posterior region were fabricated by a 3-dimensional (3D) printer. The analogs were submerged from the gingival margin to ensure four exposure heights of the scanbody: 10, 8, 6, and 4 mm. . The master models were then scanned with D2000 dental laboratory scanner as the reference models. An intraoral scanner obtained ten test models for each group. After aligning the scanbody library file, the related files were imported into inspection software for superimposition by a local fit algorithm based on the adjacent teeth. RESULTS: 3D trueness was significantly decreased at 6 and 4 mm scanbody exposure at the anterior region. In comparison, a significant decrease was only seen at 4 mm scanbody exposure at the posterior region. 3D precision was significantly decreased at 4 mm scanbody exposure at both anterior and posterior regions. CONCLUSION: The exposure height of the scanbody influenced the accuracy of the digital implant impression, according to the implant positions. Scanbody exposure of less than 6 mm at the anterior region and 4 mm scanbody exposure at the posterior region could lead to increased deviations, but still in the tolerance range. CLINICAL SIGNIFICANCE: The scanbody exposure height less than 6 mm at the anterior region and 4 mm scanbody exposure height at the posterior region could lead to significantly increased deviations. Though these deviations may be still in the clinically acceptable range, caution should be taken.

Ebselen restores peri-implantitis-induced osteogenic inhibition via suppressing BMSCs ferroptosis.

It is hard to reconstruct bone defects in peri-implantitis due to osteogenesis inhibited by excessive reactive oxygen species (ROS). Ferroptosis, a recently identified regulated cell death characterized by iron- and ROS- dependent lipid peroxidation, provides us with a new explanation. Our study aims to explore whether ferroptosis is involved in peri-implantitis-inhibited osteogenesis and confirm ebselen, an antioxidant with glutathione peroxidase (GPx)-like activity, could inhibit ferroptosis and promote osteogenesis in peri-implantitis. In this study, we used LPS to mimic the microenvironment of peri-implantitis. The osteogenic differentiation of bone-marrow-derived mesenchymal stem cells (BMSCs) was assessed by alkaline phosphatase (ALP), Alizarin Red S, and mRNA and protein expression of osteogenic-related markers. Ferroptosis index analysis included iron metabolism, ROS production, lipid peroxidation and mitochondrial morphological changes. Iron overload, reduced antioxidant capability, excessive ROS, lipid peroxidation and the characteristic mitochondrial morphological changes of ferroptosis were observed in LPS-treated BMSCs, and adding Ferrostatin-1 (Fer-1) restored the inhibitory effect of ferroptosis on osteogenic differentiation of BMSCs. Furthermore, ebselen ameliorated LPS-induced ferroptosis and osteogenic inhibition, which were reversed by erastin. Our results demonstrated that ferroptosis is involved in osteogenic inhibition in peri-implantitis and ebselen could attenuate osteogenic dysfunction of BMSCs via inhibiting ferroptosis.

Zoledronic acid affects the process of Porphyromonas gingivalis infecting oral mucosal epithelial barrier: An in-vivo and in-vitro study.

Zoledronic acid (ZA), one of the commonly used bisphosphonates, is mainly used for bone-metabolic diseases. Studies proved that ZA has adverse effects on oral soft tissues. As the first line of innate immunity, the gingival epithelium could be infected by periodontal pathogens, which is a key process of the initiation of periodontal diseases. Yet, how ZA affects the periodontal pathogens infecting the epithelial barrier remains unclear. This study aimed to investigate the influences of ZA on the process of Porphyromonas gingivalis (P. gingivalis) infecting the gingival epithelial barrier via in-vitro and in-vivo experiments. In the in-vitro experiments, under the condition of different concentrations of ZA (0, 1, 10, and 100 µM), P. gingivalis was used to infect human gingival epithelial cells (HGECs). The infections were detected by transmission electron microscope and confocal laser scanning microscope. Besides, the internalization assay was applied to quantify the P. gingivalis, which infected the HGECs, in the different groups. To evaluate the expression levels of pro-inflammatory cytokines, including interleukin (IL)-1ß, IL-6, and IL-8, by infected HGECs, real-time quantitative reverse transcription-polymerase chain reactions were applied. In the in-vivo experiments, rats were given ZA solution (ZA group) or saline (control group) by tail intravenous injection for 8 weeks. Subsequently, we put ligatures around the maxillary second molars of all the rats and inoculated P. gingivalis to the gingiva every other day from day 1 to day 13. The rats were sacrificed on days 3, 7, and 14 for micro-CT and histological analyses. The in-vitro results manifested that the quantity of P. gingivalis that had infected HGECs increased with the ZA concentrations. Pro-inflammatory cytokines expression by HGECs were significantly increased by 100 µM ZA. In the in-vivo study, compared to the control group, more P. gingivalis was detected in the superficial layer of gingival epithelium in the ZA group. Besides, ZA significantly increased the expression level of IL-1ß on day 14 and IL-6 on days 7 and 14 in gingival tissues. These findings suggest that the oral epithelial tissues of patients who receive high-dose ZA treatment may be more susceptible to periodontal infections, resulting in severe inflammatory conditions.

Evaluation of Different Reverse Osmosis Membranes for Textile Dyeing and Finishing Wastewater Reuse.

Different commercial reverse osmosis (RO) membranes from Vontron and DuPont Filmtec were evaluated for textile dyeing and finishing wastewater (TDFW) reuse in China. All six tested RO membranes produced qualified permeate meeting TDFW reuse standards at a water recovery ratio (WRR) of 70% in single batch tests. The rapid decline of apparent specific flux at WRR over 50% was mainly ascribed to feed osmotic pressure increase caused by concentrating effects. Multiple batch tests using Vontron HOR and DuPont Filmtec BW RO membranes with comparable permeability and selectivity demonstrated the reproducibility and showed low fouling development. The occurrence of carbonate scaling on both RO membranes was identified by scanning electron microscopy and energy disperse spectroscopy. No obvious organic fouling was detected on both RO membranes by attenuated total reflectance Fourier transform infrared spectrometry. From the orthogonal tests, with an integrated RO membrane performance index (i.e., 25% rejection ratio of total organic carbon + 25% rejection ratio of conductivity + 50% flux ratio of final to initial) as a target, the optimal parameters were determined as WRR of 60%, cross-flow velocity (CFV) of 1.0 m/s, temperature (T) of 20 °C for both RO membranes, while trans-membrane pressures (TMP) of 2 and 4 MPa were optimal for Vontron HOR RO membrane and DuPont Filmtec BW RO membrane, respectively. Both RO membranes with the optimal parameters produced good permeate quality for TDFW reuse and kept a high flux ratio of final to initial, demonstrating the effectiveness of the orthogonal tests.