Serine Metabolism Regulates the Replicative Senescence of Human Dental Pulp Cells through Histone Methylation.

Tissue regeneration therapy based on human dental pulp cells (hDPCs) faces the distinct challenge of cellular senescence during massive expansion in vitro. To further explore the regulatory mechanism of cellular senescence in hDPCs, we conduct experiments on young cells (Passage 5, P5) and replicative senescent (Passage 12, P12) hDPCs. The results confirm that hDPCs undergo replicative senescence with passaging, during which their ability to proliferate and osteogenic differentiation decreases. Notably, during replicative senescence, phosphoglycerate dehydrogenase (PHGDH), the key enzyme of the serine synthesis pathway (SSP), is significantly downregulated, as well as S-adenosylmethionine (SAM) levels, resulting in reduced H3K36me3 modification on Sirtuin 1 (SIRT1)and Runt-related transcription factor 2 (RUNX2) promoters. Inhibition of PHGDH leads to the same phenotype as replicative senescence. Serine supplementation fails to rescue the senescence phenotype caused by replicative senescence and inhibitors, in which folate metabolism-related genes, including serine hydroxymethyl transferase 2 (SHMT2), methylenetetrahydrofolate dehydrogenase 1(MTHFD1), methylenetetrahydrofolate dehydrogenase 2(MTHFD2), are notably decreased. Our research raised a possibility that PHGDH may be involved in cellular senescence by affecting folate metabolism and histone methylation in addition to serine biosynthesis, providing potential targets to prevent senescence.

Microbial Necromass, Lignin, and Glycoproteins for Determining and Optimizing Blue Carbon Formation.

Coastal wetlands contribute to the mitigation of climate change through the sequestration of "blue carbon". Microbial necromass, lignin, and glycoproteins (i.e., glomalin-related soil proteins (GRSP)), as important components of soil organic carbon (SOC), are sensitive to environmental change. However, their contributions to blue carbon formation and the underlying factors remain largely unresolved. To address this paucity of knowledge, we investigated their contributions to blue carbon formation along a salinity gradient in coastal marshes. Our results revealed decreasing contributions of microbial necromass and lignin to blue carbon as the salinity increased, while GRSP showed an opposite trend. Using random forest models, we showed that their contributions to SOC were dependent on microbial biomass and resource stoichiometry. In N-limited saline soils, contributions of microbial necromass to SOC decreased due to increased N-acquisition enzyme activity. Decreases in lignin contributions were linked to reduced mineral protection offered by short-range-ordered Fe (FeSRO). Partial least-squares path modeling (PLS-PM) further indicated that GRSP could increase microbial necromass and lignin formation by enhancing mineral protection. Our findings have implications for improving the accumulation of refractory and mineral-bound organic matter in coastal wetlands, considering the current scenario of heightened nutrient discharge and sea-level rise.

Deep learning in the diagnosis for cystic lesions of the jaws: a review of recent progress.

Cystic lesions of the gnathic bones present challenges in differential diagnosis. In recent years, artificial intelligence (AI) represented by deep learning (DL) has rapidly developed and emerged in the field of dental and maxillofacial radiology (DMFR). Dental radiography provides a rich resource for the study of diagnostic analysis methods for cystic lesions of the jaws and has attracted many researchers. The aim of the current study was to investigate the diagnostic performance of DL for cystic lesions of the jaws. Online searches were done on Google Scholar, PubMed, and IEEE Xplore databases, up to September 2023, with subsequent manual screening for confirmation. The initial search yielded 1862 titles, and 44 studies were ultimately included. All studies used DL methods or tools for the identification of a variable number of maxillofacial cysts. The performance of algorithms with different models varies. Although most of the reviewed studies demonstrated that DL methods have better discriminative performance than clinicians, further development is still needed before routine clinical implementation due to several challenges and limitations such as lack of model interpretability, multicentre data validation, etc. Considering the current limitations and challenges, future studies for the differential diagnosis of cystic lesions of the jaws should follow actual clinical diagnostic scenarios to coordinate study design and enhance the impact of AI in the diagnosis of oral and maxillofacial diseases.

Effect of offset on the precision of 3D-printed orthognathic surgical splints.

OBJECTIVE: This study evaluated the effect of offset on the precision of three-dimensional (3D)-printed splints, proposing to optimize the splint design to compensate for systematic errors. MATERIALS AND METHODS: 14 resin model sets were scanned and offset as a whole by given distances (0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, and 0.40 mm). Intermediate splints (ISs) and final splints (FSs) were generated from the non-offset and offset models and grouped correspondingly, named as splint type-offset value, IS-0.05, for instance. Dentitions occluded with the splint were scanned. Translational and rotational deviations of the lower dentition relative to the upper dentition were 3D measured. RESULTS: Deviations of ISs and FSs were more evident in the vertical and pitch dimensions, and were mostly acceptable in other dimensions. ISs with offset ≥ 0.05 mm showed vertical deviations significantly below 1 mm (P < 0.05) while ISs with 0.10- to 0.30-mm offsets had pitch rotations significantly lower than 1° (P < 0.05). The Pitch of IS-0.35 was significantly larger than ISs with 0.15- to 0.30-mm offsets (P < 0.05). Meanwhile, FSs fit better as the offset increased and FSs with offsets ≥ 0.15 mm all had deviations significantly lower than 1 mm (for translation) or 1° (for rotation) (P < 0.05). CONCLUSIONS: Offset affects the precision of 3D-printed splints. Moderate offset values of 0.10 to 0.30 mm are recommendable for ISs. Offset values ≥ 0.15 mm are recommended for FSs in cases with stable final occlusion. CLINICAL RELEVANCE: This study found the optimal offset ranges for 3D-printed ISs and FSs via a standardized protocol.

Mandibular Reconstruction Using Iliac Flap Based on Occlusion-Driven Workflow Transferred by Digital Surgical Guides.

PURPOSE: The current standard for mandibular reconstruction is a contour-based approach using a fibular flap offering good cosmetic results but challenging to reconstruct using dental implants. An iliac flap is more amenable to implant placement and better suited for occlusion-driven reconstruction. We aimed to describe an occlusion-driven workflow that involves the use of digital surgical guides to perform mandibular reconstruction using an iliac flap; we also aimed to compare our results to those we achieved with conventional contour-based reconstruction. METHODS: This was a retrospective cohort study. All patients who underwent mandibular reconstruction with an iliac flap at our university hospital between September 2017 and December 2019 were considered eligible for the study. The inclusion criteria included mandibular defects after tumor ablation and stable preoperative occlusal relationship. The exclusion criteria were as follows: defects involving the condyle and ramus, temporomandibular joint disease, and obvious preoperative nontumor-related facial asymmetry. To evaluate surgical outcomes, patients were assigned to 2 groups based on the implemented surgical workflow: the occlusion-driven and traditional contour-driven groups. The intermaxillary distance, intermaxillary angle, surface deviation, and implantation rates were compared between the 2 groups. The operating time, length, and number of iliac bone segments were recorded. Intergroup differences were investigated using an independent samples t test and Fisher exact test. RESULTS: Overall, 24 patients were included (13 in the occlusion-driven group and 11 in the contour-driven group). Implantation rate was higher in the occlusion-driven group (61.5%) compared with the contour-driven group (18.2%; P = .047). The average acceptable intermaxillary distance was greater in the occlusion-driven group (92.3 ± 27.7%) than in the contour-driven group (47.0 ± 47.6%; P = .01). The average intermaxillary angle was 88.2 ± 8.4° in the occlusion-driven group and 76.4 ± 10.3° in the contour-driven group (P < .01). CONCLUSIONS: Digital surgical guides can precisely transfer virtual surgical planning to real-world mandibular surgery. An occlusion-driven workflow might provide a better intermaxillary jaw relationship than traditional contour-driven surgical procedures, resulting in improved mastication.

Effectiveness of the attachment position in molar intrusion with clear aligners: a finite element study.

OBJECTIVE: To evaluate the biomechanical effects of different attachments' position for maxillary molar intrusion with clear aligner treatment by finite element analysis. METHODS: Cone-beam computed tomography images of a patient with supra-eruption of the maxillary second molars were selected to construct three-dimensional models of the maxilla, periodontal ligaments, dentition, and clear aligner. The models were divided into four groups depending on the attachment location on the first molar: (1) no attachment (NA), (2) buccal attachment (BA), (3) palatal attachment (PA), and (4) bucco-palatal attachment (BPA). After applying an intrusion of 0.2 mm on the second molar, displacements and stress distributions of the teeth, aligner, and periodontal ligament were analyzed with the finite element software. RESULTS: All groups displayed equivalent movement patterns of aligners. The NA and BA groups showed buccal tipping of the second molar, while the PA group showed palatal tipping. The BPA group had the highest intruding value and the lowest buccal/palatal tipping value. All groups showed mesial tipping of the second molar. Stress distribution in the periodontal ligament strongly correlated with the attachment position. The BPA group showed the best stress distribution. CONCLUSION: Combined BA and PA could effectively prevent buccal and palatal tipping and showed the best efficiency in intruding the second molar. The second molar showed an unavoidable tendency to tip mesially, regardless of the attachment position.

The Chemistry of Organic Contrast Agents in the NIR-II Window.

Optical imaging, especially fluorescence and photoacoustic imaging, is a non-invasive imaging approach with high spatial and temporal resolution and high sensitivity, compared to positron emission tomography (PET) or magnetic resonance imaging (MRI). Due to the merits of imaging using the second near-infrared (NIR-II) window, like deeper penetration depth, high signal-to-noise ratio, high resolution, and low tissue damage, researchers have devoted great effort to developing contrast agents with NIR-II absorption or emission. In this Review, we summarize recently developed organic luminescent and photoacoustic materials, ranging from small molecules to conjugated polymers. Then, we systematically introduce engineering strategies and describe the imaging performance classified by the skeleton cores. Finally, we elucidate the challenges and prospects of these NIR-II organic dyes for potential clinical applications. We expect our summary can inspire researchers to expand the spectrum of NIR-II contrast agents for diverse bioapplications.

Secular trends in severe periodontitis incidence, prevalence and disability-adjusted life years in five Asian countries: A comparative study from 1990 to 2017.

AIMS: To investigate secular trends in severe periodontitis incidence, prevalence and disability-adjusted life year (DALY) rates in China, India, Japan, South Korea and Thailand from 1990 to 2017. MATERIALS AND METHODS: Data were obtained from the "Global Burden of Disease Study" 2017. The annual percentage change and average annual percentage change were calculated using Joinpoint regression analysis. The independent age, period and cohort effects were estimated by age-period-cohort analysis. RESULTS: From 1990 to 2017, the overall age-standardized incidence, prevalence and DALY rates increased in China, Japan and India, while decreasing in South Korea and Thailand. The highest incidence, prevalence and DALY rates were in India. By APC analysis, the age effect presented increase in 20-59 years in China, Japan and South Korea, 20-54 years in India and 20-64 years in Thailand; the period effect showed progressive increases in five countries, with the most significant increase shown in China; the cohort effect showed monotonic decreases with birth cohort in five countries. CONCLUSIONS: Severe periodontitis poses a serious burden in Asian countries, especially China and India. We suggest raising people's awareness of periodontal health and providing professional interventions in these countries, especially for high-risk groups, such as younger people aged ≤65 years.

Key Physicochemical Properties Dictating Gastrointestinal Bioaccessibility of Microplastics-Associated Organic Xenobiotics: Insights from a Deep Learning Approach.

A potential risk from human uptake of microplastics is the release of plastics-associated xenobiotics, but the key physicochemical properties of microplastics controlling this process are elusive. Here, we show that the gastrointestinal bioaccessibility, assessed using an in vitro digestive model, of two model xenobiotics (pyrene, at 391-624 mg/kg, and 4-nonylphenol, at 3054-8117 mg/kg) bound to 18 microplastics (including pristine polystyrene, polyvinyl chloride, polyethylene terephthalate, polypropylene, thermoplastic polyurethane, and polyethylene, and two artificially aged samples of each polymer) covered wide ranges: 16.1-77.4% and 26.4-83.8%, respectively. Sorption/desorption experiments conducted in simulated gastric fluid indicated that structural rigidity of polymers was an important factor controlling bioaccessibility of the nonpolar, nonionic pyrene, likely by inducing physical entrapment of pyrene in porous domains, whereas polarity of microplastics controlled bioaccessibility of 4-nonylphenol, by regulating polar interactions. The changes of bioaccessibility induced by microplastics aging corroborated the important roles of polymeric structures and surface polarity in dictating sorption affinity and degree of desorption hysteresis, and consequently, gastrointestinal bioaccessibility. Variance-based global sensitivity analysis using a deep learning neural network approach further revealed that micropore volume was the most important microplastics property controlling bioaccessibility of pyrene, whereas the O/C ratio played a key role in dictating the bioaccessibility of 4-nonylphenol in the gastric tract.

[Material basis and mechanism of Xiao'er Resuqing Oral Liquid on hand, foot and mouth disease based on network pharmacology and molecular docking].

This paper aimed to investigate the active components and molecular mechanism of Xiao'er Resuqing Oral Liquid on hand, foot and mouth disease(HFMD) based on network pharmacology and molecular docking methods. The potential active components of 8 herbs in Xiao'er Resuqing Oral Liquid were selected through Traditional Chinese Medicine Systems Pharmacology Database(TCMSP), Batman database and relevant literature consultation. Then related targets for the medicine were analyzed through PubChem and Swiss Target Prediction database, while related targets for HFMD were analyzed through GeneCards platform. The common targets for medicine and disease were put into STRING database to obtain the potential targets of Xiao'er Resuqing Oral Liquid for treatment of HFMD. The Cytoscape software was used to establish the "herbs-components-targets-disease" network. The protein-protein interaction(PPI) network was constructed based on STRING platform and Cytoscape software to screen the core targets. Based on Metascape platform, GO function enrichment analysis and KEGG signal pathway enrichment analysis were carried out. The main active components and potential key targets of Xiao'er Resuqing Oral Liquid were verified by molecular docking with Autodock vina 1.1.2 software. A total of 118 potential active components and 123 potential targets for treatment of HFMD were collected. PPI network indicated a total of 23 key targets, such as AKT1, MAPK1, IL6, VEGFA, EGFR, TNF, HRAS, CCND1, and CXCL8. GO function enrichment analysis results showed that there were 381 GO biological processes, 127 GO cellular components, and 117 GO molecular functions(P<0.01). KEGG enrichment analysis showed that 116 signal pathways were obtained(P<0.01), and the results showed that it was mainly associated with TNF signal pathway, IL-17 signal pathway, inflammatory mediator regulation of TRP channels, and cytokine-cytokine receptor interaction. Molecular docking results showed that the main active components all had a high binding ability with the main potential key targets. This study preliminarily investigated the multi-pathways, multi-targets and multi-components molecular mechanism of Xiao'er Resuqing Oral Liquid for treatment of HFMD, providing theoretical references for further researches on its active components and action mechanism.

Construction of a Polypyrrole-Based Multifunctional Nanocomposite for Dual-Modal Imaging and Enhanced Synergistic Phototherapy against Cancer Cells.

Design and construction of multifunctional theranostic nanoplatforms are still desired for cancer-effective treatment. Herein, a kind of polypyrrole (PPy)-based multifunctional nanocomposite was designed and successfully constructed for dual-model imaging and enhanced synergistic phototherapy against cancer cells. Through graphene oxide (GO) sheet coating, PPy nanoparticles (NPs) were effectively combined with polyethylene glycol chains, Au NPs, and IR820 molecules. The obtained PGPAI NPs showed promising ability for photoacoustic/computed tomography imaging. Under near-infrared light irradiation, the PPy core and IR820 molecule effectively generated heat and reactive oxygen species (ROS), respectively. Furthermore, the loaded Au NPs owning catalase-like activity produced oxygen by decomposing H2O2 (up-regulated in tumor region), enhancing the oxygen-dependent photodynamic therapy efficacy. The formed PGPAI NPs were also proved to own desirable photothermal conversion efficiency, photothermal stability, colloidal stability, cytocompatibility, and cellular internalization behaviors. Furthermore, cell assay demonstrated that PGPAI NPs displayed enhanced synergistic phototherapy efficacy against cancer cells. These developed multifunctional nanoplatforms are promising for effective cancer theranostic applications.

Enhanced Photoacoustic and Photothermal Effect of Functionalized Polypyrrole Nanoparticles for Near-Infrared Theranostic Treatment of Tumor.

Functionalized nanomaterials with near-infrared (NIR) responsive capacity are quite promising for theranostic treatment of tumors, but formation of NIR responsive nanomaterials with enhanced theranostic ability and excellent biocompatibility is still very challenging. Herein, PEGylated indocyanine green (ICG)-loaded polypyrrole nanoparticles (PPI NPs) were designed and successfully formed through selecting polydopamine as the linkage between each component, demonstrating enhanced NIR responsive theranostic ability against tumor. By combining in vitro cell study with in vivo assay, the formed PPI NPs were proven to be fantastically biocompatible while effectively internalization in HeLa cells and retention in HeLa tumor were demonstrated by in vitro flow cytometry/confocal measurement and in vivo photoacoustic imaging assay. With the guidance of photoacoustic imaging, successful photothermal ablation of tumor was achieved by treatment with PPI NPs plus laser, which was much more effective than the group treated with NPs free of ICG. The combined enhanced photoacoustic and photothermal effect is mainly ascribed to the functionalized polypyrrole nanoparticles, which could accumulate in the tumor site more effectively with a relatively longer retention time taking advantage of the nanomaterial-induced endothelial leakiness phenomenon. All these results demonstrating that this designed PPI NPs possessing enhanced NIR responsive property hold great promise for tumor NIR theranostic applications.

Peptide-Lipid Interaction Sites Affect Vesicles' Responses to Antimicrobial Peptides.

This article presents coarse-grained molecular dynamics simulations of pore-forming antimicrobial peptide melittin and its interactions with vesicles composed of a mixture of zwitterionic and anionic phospholipids. Besides creating holes in the membrane, the adsorption of melittin also induces vesicle budding, which can develop into vesiculation at high peptide concentrations, as well as vesicle invagination, which can eventually result in a corrugated membrane surface. These rich morphology changes are mediated by the curvature of the vesicles and the peptide concentration. Highly curved vesicles favor the recruitment of melittins with a higher density of binding sites. The peptides mainly penetrate into the membrane surface in monomers via hydrophobic interaction. Lowly curved vesicles recruit melittins with a low density of binding sites. Surplus peptides are prone to form oligomers and shallowly adsorb on the surface of membrane via electrostatic interaction. The penetration of monomers induces membrane pore formation and positive membrane curvature, which promote vesicle budding. The adsorption of oligomers induces negative membrane curvature, which promotes vesicle invagination. This work demonstrates that antimicrobial peptides adopt multiple actions to destroy bacterial membranes.

Assessing the Quality of Life in Patients With Dentofacial Deformities Before and After Orthognathic Surgery.

PURPOSE: This study aimed to assess the effect of health-related quality of life (QoL) among patients with dentofacial deformities who underwent orthognathic surgery compared with a control group without dentofacial deformities by use of generic oral health and condition-specific approaches. PATIENTS AND METHODS: In this prospective study, 2 questionnaires were administered to 85 patients (31 male and 54 female patients) who were evaluated before undergoing orthognathic surgery. The Short Form Oral Health Impact Profile Questionnaire (OHIP-14) and the Orthognathic Quality of Life Questionnaire (OQLQ) were administered before and 5 to 7 months after orthognathic surgery. The control group comprised 96 young university student volunteers without dentofacial deformities. RESULTS: The questionnaires were collected 5 to 7 months after surgery. The preoperative scores of the patients and the control group were contrasted separately. The respondents' postoperative OHIP-14 and OQLQ scores were significantly lower (P < .001 for total scores). The preoperative OQLQ scores for all domains were significantly higher among the patients than among the controls (P < .001 for total scores), whereas the total scores and 3 subscale scores of the OHIP-14 in the functional and psychological domains were significantly higher among the patients than among the controls (P < .05 for total scores). The preoperative and postoperative OQLQ total scores were remarkably different between male and female patients (P < .05). The postoperative OQLQ total scores were considerably higher in older patients than in younger patients (P < .05). All patients in the Class III group who underwent double-jaw surgery showed remarkable changes after surgery (P < .001 for total scores). CONCLUSIONS: Patients with dentofacial deformities had a poorer QoL compared with the healthy population, especially in functional and psychological aspects. Orthognathic surgery had a significant positive impact on QoL. Patients with Class III malocclusion who underwent double-jaw surgery seemingly benefitted the most after surgery.

Carbon constrains fungal endophyte assemblages along the timberline.

The alpha diversity of foliar fungal endophytes (FEs) in leaves of Betula ermanii in a subalpine timberline ecotone on Changbai Mountain, China increased with elevation. There were also significant differences in beta diversity along the elevation gradient. Among the environmental variables analysed, leaf carbon significantly increased with elevation, and was the most significant environmental factor that constrained the alpha and beta diversity in the FE communities. Tree height and the cellulose, lignin, and carbon/nitrogen ratio of the leaves also affected the FE assemblages. When controlled for the effects of elevation, leaf carbon was still the main driver of changes in evenness, Shannon diversity and FE community composition. The results offered clues of the carbon acquisition strategy of the foliar FEs across this cold terrain. There was strong multicollinearity between both annual precipitation and temperature, with elevation (|Pearson r| > 0.986), so the effects of these climatic variables were impossible to separate; however, they may play key roles, and the direct effects of both warrant further investigation. As pioneer decomposers of leaf litter, variations in diversity and community composition of FE measured here may feedback and influence carbon cycling and dynamics in these forest ecosystems.

Effects of occlusion on mandibular morphology and architecture in rats.

BACKGROUND: A rodent occlusal hypofunction model has been widely established in jawbone-related studies. However, the effects of occlusal stimuli, with total elimination of molar contacts, and its rehabilitation on mandibular remodeling remain unclear. MATERIALS AND METHODS: Forty-eight 5-wk-old Sprague-Dawley male rats were used. Twenty-four experimental rats underwent occlusal hypofunction by insertion of a bite-raising appliance. Twenty-four rats received no treatment (control group). Two weeks later, half the experimental rats (occlusal hypofunction group) were killed; the appliance was removed from the remaining experimental rats (recovery group) for two additional weeks before killing. Control animals were killed biweekly. Body weight and masseter muscle weight were measured, and the mandibles were subjected to micro-computed tomography to evaluate the mandibular morphology and cortical bone characteristics. The expressions of osteoblast- and osteoclast-related genes were evaluated with quantitative polymerase chain reaction. RESULTS: No significant body weight differences were observed between the experimental and control rats. However, lighter masseter muscle, shorter mandibular incisor crown, mandibular body and ramus, and higher mandibular alveolar process and first molar fossae were observed in the occlusal hypofunction group. Moreover, the cortical bone characteristics associated with the expression of osteoblast- and osteoclast-related genes were remarkably different in the central and posterior mandible in the occlusal hypofunction group. At the 2-wk recovery time point after occlusal stimuli, the altered parameters in the masseter and mandible returned to normal levels. CONCLUSIONS: Mandibular remodeling via bone turnover is region specific for altered occlusal stimuli. Normal occlusion is an important determinant of the mandibular morphology and architecture.

Novel POSS-PCU Nanocomposite Material as a Biocompatible Coating for Quantum Dots.

Quantum dots (QDs) are fluorescent nanoparticles with unique photophysical properties that enable them to potentially replace traditional organic dyes and fluorescent proteins in various bioimaging applications. However, the inherent toxicity of their cores based on cadmium salts limits their widespread biomedical use. We have developed a novel nanocomposite polymer emulsion based on polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) that can be used to coat quantum dots to nullify their toxicity and enhance photostability. Here we report the synthesis and characterization of a novel POSS-PCU nanocomposite polymer emulsion and describe its application for coating QDs for biological application. The polymer was synthesized by a process of emulsion polymerization and formed stable micelles of ∼33 nm in diameter. CdTe/CdS/ZnS QDs were efficiently stabilized by the polymer emulsion through encapsulation within the polymer micelles. Characterization studies showed no significant change in the unique photophysical properties of QDs after coating. The polymer was biocompatible to HepG2, HUVECs, and mouse skeletal muscle cells at 2.5% after 24 h exposure on in vitro testing. Polymer encapsulated QDs showed enhanced photostability on exposure to high degrees of UV irradiation and air as well as significantly reduced cytotoxicity on exposure to HepG2 cells at 30 µg/mL for 24 h. We have therefore concluded that the POSS-PCU polymer emulsion has the potential to make a biocompatible and photostable coating for QDs enabling a host of biomedical applications to take this technology to the next level.

Phylogenetic diversity of Archaea in the intestinal tract of termites from different lineages.

Termites are among the few arthropods that emit methane to the atmosphere, which is a significant source of global greenhouse gas due to their huge biomass on earth. In this study, phylogenetic diversity of Archaea of five termite species from different lineages were analyzed based on 16S rRNA genes. Archaea associated with wood-feeding lower termite, R. chinensis were exclusively Methanobrevibacter in the order Methanobacteriales. This type of methanogens was also found in Nasutitermes sp. and Microcerotermes sp. but not in the fungus-cultivating termites, Odontotermes formosanus and Macrotermes barneyi, which harbor Archaea of the order Methanoplasmatales and Methanosarcinales in their guts. Archaeal diversity of wood-feeding higher termites was higher than wood-feeding lower termites. The highest archaeal diversity was found in Nasutitermes sp. In addition to methanogens affiliated with the orders Methanobacteriales, Methanomicrobiales, and Methanoplasmatales, 37% of archaeal clones were affiliated with non-methanogenic Thaumarchaeota. The results of this study will be significant for further understanding of symbiotic relationship between intestinal microbiota and termites.

External stimuli-triggered photodynamic and sonodynamic therapies in combination with hybrid nanomicelles of ICG@PEP@HA: laser vs. ultrasound.

The concept of combining external medical stimuli with internal functional biomaterials to achieve cancer-oriented treatments is being emergingly developed. Optical and acoustical activations have shown particular promise as non-invasive regulation modalities in cancer treatment and intervention. It is always challenging to leverage the contributions of optical and acoustical stimuli and find appropriate biomaterials to optimally match them. Herein, a type of hybrid nanomicelle (ICG@PEP@HA) containing ICG as a photo/sonosensitizer, an amphiphilic peptide for membrane penetration and hyaluronic acid for cluster determinant 44 (CD44) targeting was fabricated. Triggered by the external stimuli of laser and US irradiation, their photo/sonothermal performance, in vitro reactive oxygen species (ROS) production capability and tumor-targeting efficiency have been systematically evaluated. It was interestingly found that the external stimulus of laser irradiation induced a greater quantity of ROS, which resulted in significant cell apoptosis and tumor growth inhibition in the presence of ICG@PEP@HA. The individual analyses and corresponding rationales have been investigated. Meanwhile, these hybrid nanomicelles were administered into MDA-MB-231 tumor-bearing nude mice for PDT and SDT therapies and their biocompatibility assessment, and a prevailing PDT efficacy and reliable bio-safety have been evidenced based on the hematological analysis and histochemical staining. In summary, this study has validated a novel pathway to utilize these hybrid nanomicelles for laser/US-triggered localized tumor treatment, and the treatment efficiency may be leveraged by different external stimuli sources. It is also expected to give rise to full accessibility to clinical translations for human cancer treatments by means of the as-reported laser/US-nanomicelle combination strategy.

Optimal settings for different tooth types in the virtual bracket removal technique.

OBJECTIVES: To determine the optimal settings for reconstructing the buccal surfaces of different tooth types using the virtual bracket removal (VBR) technique. MATERIALS AND METHODS: Ten postbonded digital dentitions (with their original prebonded dentitions) were enrolled. The VBR protocol was carried out under five settings from three commonly used computer-aided design (CAD) systems: OrthoAnalyzer (O); Meshmixer (M); and curvature (G2), tangent (G1), and flat (G0) from Geomagic Studio. The root mean squares (RMSs) between the reconstructed and prebonded dentitions were calculated for each tooth and compared with the clinically acceptable limit (CAL) of 0.10 mm. RESULTS: The overall prevalences of RMSs below the CAL were 66.80%, 70.08%, 62.30%, 94.83%, and 56.15% under O, M, G2, G1, and G0, respectively. For the upper dentition, the mean RMSs were significantly lower than the CAL for all tooth types under G1 and upper incisors and canines under M and G2. For the lower dentition, the mean RMSs were significantly lower than the CAL for all tooth types under G1 and lower incisors and canines under M, G2, and G0 (all P < .05). Additionally, the mean RMSs of all teeth under G1 were significantly lower than those under the other settings (all P < .001). CONCLUSIONS: The optimal settings varied among different tooth types. G1 performed best for most tooth types compared to the other four settings.