Microbial- and host immune cell-derived extracellular vesicles in the pathogenesis and therapy of periodontitis: A narrative review

Periodontitis is a chronic inflammatory disease caused by dysbiotic biofilms and destructive host immune responses. Extracellular vesicles (EVs) are circulating nanoparticles released by microbes and host cells involved in cell-to-cell communication, found in body biofluids, such as saliva and gingival crevicular fluid (GCF). EVs are mainly involved in cell-to-cell communication, and may hold promise for diagnostic and therapeutic purposes. Periodontal research has examined the potential involvement of bacterial- and host-cell-derived EVs in disease pathogenesis, diagnosis, and therapy, but data remains scarce on immune cell- or microbial-derived EVs. In this narrative review, we first provide an overview of the role of microbial and host-derived EVs on disease pathogenesis. Recent studies reveal that Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans-derived outer membrane vesicles (OMVs) can activate inflammatory cytokine release in host cells, while M1 macrophage EVs may contribute to bone loss. Additionally, we summarised current in vitro and pre-clinical research on the utilisation of immune cell and microbial-derived EVs as potential therapeutic tools in the context of periodontal treatment. Studies indicate that EVs from M2 macrophages and dendritic cells promote bone regeneration in animal models. While bacterial EVs remain underexplored for periodontal therapy, preliminary research suggests that P. gingivalis OMVs hold promise as vaccine candidates. Finally, we acknowledge the current limitations present in the field of translating immune cell derived EVs and microbial derived EVs in periodontology. It is concluded that microbial and host immune cell-derived EVs have a role in periodontitis pathogenesis and hence may be useful for studying disease pathophysiology, and as diagnostic and treatment monitoring biomarkers.

Effects of a 'Rebuilding Myself' intervention on enhancing the adaptability of cancer patients to return to work: a randomized controlled trial

OBJECTIVES

To explore the effects of a 'Rebuilding Myself' intervention on enhancing the adaptability of cancer patients to return to work.

METHODS

A single-center, single-blind, randomized controlled trial design was used. Eligible patients who were receiving routine hospital treatment were recruited from the university-affiliated hospital in our city. Patients in the control group only received usual care, while patients in the intervention group received additional 'Rebuilding Myself' intervention. Adaptability to return to work, self-efficacy of returning to work, mental resilience, quality of life and work ability were measured at baseline, the 6th and 12th of the intervention. The general estimation equations were used to compare the overall changes of each outcome index between the two groups at different time points. Considering that there may be patient shedding and rejection, Per-Protocol and Intention-to-Treat analysis were used to analyze the data in this study.

RESULTS

There were statistically significant differences between the two groups of patients in the cancer patients' adaptability to return to work, self-efficacy to return to work, mental resilience, work abilities, the physical, emotional, cognitive function, fatigue, insomnia and overall health status dimensions of quality of life (P < 0.05). And no significant difference was found in other dimensions (P > 0.05). The group effect, time effect, and interaction effect of patients' return to work adaptability and return to work self-efficacy were statistically significant in both groups (P < 0.05). Mental resilience, working ability, and quality of life had obvious time effect and interaction effect (P < 0.05).

CONCLUSION

This intervention could improve cancer patients' adaptability to return to work, self-efficacy to return to work, mental resilience, work abilities and quality of life. And it can be further expanded to improve the adaptability of patients to return to work, then to help patients achieve comprehensive rehabilitation.

IMPLICATIONS FOR CANCER SURVIVORS

The application of 'Rebuilding Myself' interventions can effectively improve the adaptability of cancer patients returning to work.

TRIAL REGISTRATION

This study was registered at the Chinese Clinical Trial Registry (Registration number: ChiCTR2200057943) on 23 March, 2022.

Unveiling clinical applications of bacterial extracellular vesicles as natural nanomaterials in disease diagnosis and therapeutics

Bacterial extracellular vesicles (BEVs) are naturally occurring bioactive membrane-bound nanoparticles released by both gram-negative and gram-positive bacterial species, exhibiting a multifaceted role in mediating host-microbe interactions across various physiological conditions. Increasing evidence supports BEVs as essential mediators of cell-to-cell communicaiton, influencing bacterial pathogenicity, disease mechanisms, and modulating the host immune response. However, the extent to which these BEV-mediated actions can be leveraged to predict disease onset, guide treatment strategies, and determine clinical outcomes remains uncertain, particularly in terms of their clinical translation potentials. This review briefly describes BEV biogenesis and their internalisation by recipient cells and summarises methods for isolation and characterization, essential for understanding their composition and cargo. Further, it discusses the potential of biofluid-associated BEVs as biomarkers for various diseases, spanning both cancer and non-cancerous conditions. Following this, we outline the ongoing human clinical trials of using BEVs for vaccine development. In addition to disease diagnostics, this review explores the emerging research of using natural or engineered BEVs as smart nanomaterials for applications in anti-cancer therapy and bone regeneration. This discussion extends to key factors for unlocking the clinical potential of BEVs, such as standardization of BEV isolation and characterisation, as well as other hurdles in translating these findings to the clinical setting. We propose that addressing these hurdles through collaborative research efforts and well-designed clinical trials holds the key to fully harnessing the clinical potential of BEVs. As this field advances, this review suggests that BEV-based nanomedicine has the potential to revolutionize disease management, paving the way for innovative diagnosis, therapeutics, and personalized medicine approaches. STATEMENT OF SIGNIFICANCE: Extracellular vesicles (EVs) from both host cells and bacteria serve as multifunctional biomaterials and are emerging in the fields of biomedicine, bioengineering, and biomaterials. However, the majority of current studies focus on host-derived EVs, leaving a gap in comprehensive research on bacteria-derived EVs (BEVs). Although BEVs offer an attractive option as nanomaterials for drug delivery systems, their unique nanostructure and easy-to-modify functions make them a potential method for disease diagnosis and treatment as well as vaccine development. Our work among the pioneering studies investigating the potential of BEVs as natural nanobiomaterials plays a crucial role in both understanding the development of diseases and therapeutic interventions.

Single-Cell RNA-Sequencing Reveals Heterogeneity and Transcriptional Dynamics in Porcine Circulating CD8+ T Cells

Pigs are the most important source of meat and valuable biomedical models. However, the porcine immune system, especially the heterogeneity of CD8 T cell subtypes, has not been fully characterized. Here, using single-cell RNA sequencing, we identified 14 major cell types from peripheral blood circulating cells of pigs and observed remarkable heterogeneity among CD8 T cell types. Upon re-clustering of CD8+ T cells, we defined four CD8 T cell subtypes and revealed their potential differentiation trajectories and transcriptomic differences among them. Additionally, we identified transcription factors with potential regulatory roles in maintaining CD8 T cell differentiation. The cell-cell communication analysis inferred an extensive interaction between CD8 T cells and other immune cells. Finally, cross-species analysis further identified species-specific and conserved cell types across different species. Overall, our study provides the first insight into the extensive functional heterogeneity and state transitions among porcine CD8 T cell subtypes in pig peripheral blood, complements the knowledge of porcine immunity, and enhances its potential as a biomedical model.

[Preliminary outcomes of neoadjuvant chemoimmunotherapy combined with transoral robotic surgery for locally advanced oropharyngeal squamous cell carcinoma]

Objective: To evaluate the efficacy of neoadjuvant chemoimmunotherapy (NACI) combined with transoral robotic surgery (TORS) in the treatment of locally advanced oropharyngeal squamous cell carcinoma (OPSCC). Methods: This was a retrospective study of 15 patients with locally advanced OPSCC who underwent TORS after neoadjuvant therapy (NAT) at the Department of Otolaryngology-Head and Neck Surgery of Sun Yat-sen Memorial Hospital of Sun Yat-sen University from April 2019 to February 2023. There were 12 males and 3 females, aged 31 to 74 years. Twelve cases were tonsil cancer, and 3 cases were tongue base cancer. There were 11 cases in stage Ⅲ and 4 cases in stage Ⅳ. Two patients received neoadjuvant chemotherapy and 13 patients received NACI, with 2 to 3 cycles, and all patients underwent TORS after multidisciplinary team consultation. The clinicopathological characteristics, surgical outcomes, and oncological results were summarized. Results: All surgeries were successfully completed with negative surgical margins, and no case was required conversion surgery. All patients were fed via nasogastric tubes postoperatively, with a median gastric tube stay of 7 days (range: 2-60 days). No tracheotomy was applied. There were no major complications such as postoperative bleeding. Pathological complete response (pCR) was found in 10 cases (76.9%) among the 13 patients with NACI. The follow-up time was 21 months (range: 10-47 months), and there was no death or distant metastasis. One patient with rT0N3M0 tonsil cancer had local recurrence 5 months after surgery. The 2-year overall survival and 2-year disease-free survival were respectively 100.0% and 93.3% in the 15 patients. Conclusion: NACI combined with TORS provides a safe, effective and minimally invasive treatment for patients with locally advanced oropharyngeal squamous cell carcinoma.

3D bioprinted small extracellular vesicles from periodontal cells enhance mesenchymal stromal cell function

Recent research indicates that combining 3D bioprinting and small extracellular vesicles (sEVs) offers a promising 'cell-free' regenerative medicine approach for various tissue engineering applications. Nonetheless, the majority of existing research has focused on bioprinting of sEVs sourced from cell lines. There remains a notable gap in research regarding the bioprinting of sEVs derived from primary human periodontal cells and their potential impact on ligamentous and osteogenic differentiation. Here, we investigated the effect of 3D bioprinted periodontal cell sEVs constructs on the differentiation potential of human buccal fat pad-derived mesenchymal stromal cells (hBFP-MSCs). Periodontal cell-derived sEVs were enriched by size exclusion chromatography (SEC) with particle-shaped morphology, and characterized by being smaller than 200 nm in size and CD9/CD63/CD81 positive, from primary human periodontal ligament cells (hPDLCs) and human gingival fibroblasts (hGFs). The sEVs were then 3D bioprinted in 10 % gelatin methacryloyl (GelMA) via microextrusion bioprinting. Release of sEVs from bioprinted constructs was determined by DiO-labelling and confocal imaging, and CD9 ELISA. Attachment and ligament/osteogenic/cementogenic differentiation of hBFP-MSCs was assessed on bioprinted GelMA, without and with sEVs (GelMA/hPDLCs-sEVs and GelMA/hGFs-sEVs), scaffolds. hBFP-MSCs seeded on the bioprinted sEVs constructs spread well with significantly enhanced focal adhesion, mechanotransduction associated gene expression, and ligament and osteogenesis/cementogenesis differentiation markers in GelMA/hPDLCs-sEVs, compared to GelMA/hGFs-sEVs and GelMA groups. A 2-week osteogenic and ligamentous differentiation showed enhanced ALP staining, calcium formation and toluidine blue stained cells in hBFP-MSCs on bioprinted GelMA/hPDLCs-sEVs constructs compared to the other two groups. The proof-of-concept data from this study supports the notion that 3D bioprinted GelMA/hPDLCs-sEVs scaffolds promote cell attachment, as well as ligamentous, osteogenic and cementogenic differentiation, of hBFP-MSCs in vitro.

An in vitro dynamic bioreactor model for evaluating antimicrobial effectiveness on periodontal polymicrobial biofilms: a proof-of-concept study

BACKGROUND

The aim of this study was to investigate an in vitro dynamic bioreactor model by evaluating the antimicrobial effect of clinically relevant amoxicillin doses on polymicrobial microcosm biofilms derived from subgingival plaque.

METHODS

Biofilms from pooled subgingival plaque were grown for 108  hours in control and experimental dynamic biofilm reactors. Amoxicillin was subsequently infused into the experimental reactor to simulate the pharmacokinetic profile of a standard 500 mg thrice-daily dosing regimen over 5 days and biofilms were assessed by live/dead staining, scanning electron microscopy, and quantitative polymerase chain reaction.

RESULTS

Following establishment of the oral microcosm biofilms, confocal imaging analysis showed a significant increase in dead bacteria at 8 hours (p = 0.0095), 48 hours (p = 0.0070), 96 hours (p = 0.0140), and 120 hours (p < 0.0001) in the amoxicillin-treated biofilms compared to the control biofilms. Nevertheless, viable bacteria remained in the center of the biofilm at all timepoints. Significant reductions/elimination in Campylobacter rectus, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and Peptostreptococcus anaerobius was observed among the amoxicillin-treated biofilms at the 96 and 120 hour timepoints.

CONCLUSION

A novel in vitro dynamic model of oral microcosm biofilms was effective in modeling the antimicrobial effect of a pharmacokinetically simulated clinically relevant dose of amoxicillin.

Enriched environment treatment promotes neural functional recovery together with microglia polarization and remyelination after cerebral ischemia in rats

BACKGROUND

Microglia activation and oligodendrocyte maturation are critical for remyelination after cerebral ischemia. Studies have shown that enriched environment (EE) can effectively alleviate stroke-induced neurological deficits. However, little is known about the mechanism associated with glial cells underlying the neuroprotection of EE. Therefore, this study focuses on investigating the effect of EE on activated microglia polarization as well as oligodendrogenesis in the progress of remyelination following cerebral ischemia.

METHODS

The ischemia/reperfusion (I/R) injury model was established by middle cerebral artery occlusion (MCAO) in rats. Animals executed 4 weeks of environmental intervention after performing MCAO or sham surgery and were divided into sham, MCAO, and MCAO+EE groups. Cognitive function, myelin damage, microglia activation and polarization, inflammation, oligodendrogenesis, remyelination, and protein expression of the PI3K/AKT/GSK3β signaling pathway were determined.

RESULTS

The staining of NeuN indicated that the infarct size of MCAO rats was decreased under EE. EE intervention improved animal performance in the Morris water maze test and novel object recognition test, promoting the recovery of cognitive function after I/R injury. EE treatment alleviated myelin damage in MCAO rats, as evidenced by the lower fluorescence intensity ratio of SMI-32/MBP in MCAO+EE group. EE increased the fluorescence intensity ratio of NG2+/Ki67+/Olig2+, MBP, and MOG, enhancing the proliferation and differentiation of OPCs and oligodendrogenesis after MCAO. In terms of remyelination, more myelinated axons and lower G/ratio were detected in MCAO+EE rats compared with MCAO group. Moreover, EE treatment decreased the number of Iba1+/CD86+ M1 microglia, increased the number of Iba1+/CD206+ M2 microglia, and suppressed the inflammation response after I/R injury, which could be attributed to the augmented expression of PI3K/AKT/GSK3β axis.

CONCLUSION

EE improved long‑term recovery of cognitive function after cerebral I/R injury, at least in part by promoting M2 microglia transformation through activation of the PI3K/AKT/GSK3β signaling pathway, inhibiting inflammation to provide a favorable microenvironment for oligodendrocyte maturation and remyelination. The effect of the EE on myelin and inflammation could account for the neuroprotection provided by EE.

Effect of non-surgical periodontal therapy on salivary histone deacetylases expression: A prospective clinical study

AIM

To evaluate the effect of non-surgical periodontal therapy (NSPT) on salivary histone deacetylases (HDACs) gene expression in patients with Stage III-IV periodontitis at baseline and at 3 and 6 months post NSPT treatment.

MATERIALS AND METHODS

Twenty patients completed the study. Periodontitis (as well as the corresponding staging and grading) was diagnosed according to the 2017 World Workshop Classification. Clinical measures were recorded and whole unstimulated saliva was collected at baseline and at 3 and 6 months after NSPT. The expression of 11 HDACs was determined using reverse-transcription PCR, and the respective changes over time were evaluated.

RESULTS

Six months after NSPT, significant improvements in all clinical periodontal parameters were observed, concomitant with significant up-regulation of HDAC2, 4, 6, 8, 9 and 11 expressions. Subgroup analyses of non-responders and responders revealed no significant differences in HDACs mRNA expression between groups at any time point.

CONCLUSIONS

This prospective clinical study identified longitudinal changes in salivary HDACs expression in response to NSPT, which provides new insights into the epigenetic mechanisms underlying the pathobiology of periodontitis and creates avenues for the discovery of novel biomarkers.

Comparison of conventional and endoscope-assisted partial clretain-->superficial parotidectomy for benign neoplasms of the parotid gland: a matched case-control study

Long-term tumour recurrence rates and complications of endoscope-assisted partial superficial parotidectomy (PSP) are rarely reported compared to traditional open approaches. This retrospective study included 306 patients with superficial parotid benign neoplasms who were divided into an endoscopy group (endoscope-assisted PSP, n = 102) and a control group (conventional PSP, n = 204). There were no significant differences in clinical and pathological characteristics between the two groups, except age (P = 0.001). Three patients had confirmed recurrence during a mean follow-up duration of 125.1 months. Ten (9.8%) patients in the endoscopy group and 22 (10.8%) in the control group developed transient facial nerve palsy (P = 0.792), and recovered 6 months after the operation. Nine (8.8%) and 19 (9.3%) patients, respectively, suffered from Frey syndrome (P = 0.889). A sensory deficit of the auricle occurred in 24 (23.5%) and 57 (27.9%) patients respectively (P = 0.410). Patients in the endoscopy group were more satisfied with the postoperative scar than those in the control group (P < 0.001). This study demonstrated that the endoscope-assisted PSP can be curative, with better cosmetic outcomes than the conventional approach, and does not increase the incidence of postoperative complications or the local recurrence rate.

Differentiation of Crohn's disease, ulcerative colitis, and intestinal tuberculosis by dual-layer spectral detector CT enterography

AIM

To investigate the value of radiological features and energy spectrum quantitative parameters in the differential diagnosis of Crohn's disease (CD), ulcerative colitis (UC), and intestinal tuberculosis (ITB) by dual-layer spectral detector computed tomography (CT) enterography (CTE).

MATERIALS AND METHODS

Clinical and CTE data were collected from 182 patients with CD, 29 with UC, and 51 with ITB. CT images were obtained at the enteric phases and portal phases. The quantitative energy spectrum parameters were iodine density (ID), normalised ID (NID), virtual non-contrast (VNC) value, and effective atomic number (Z-eff). The area under curve (AUC) of the receiver operating characteristic curve (ROC) was calculated.

RESULTS

The vascular comb sign (p=0.009) and enlarged lymph nodes (p=0.001) were more common in patients with CD than UC or ITB. In the differentiation of moderate-severe active CD from UC, enteric phase NID (AUC, 0.938; p<0.001) and portal phase Z-eff (AUC, 0.925; p<0.001) had the highest accuracy, which were compared separately. In the differentiation of moderate-severe active CD from ITB, enteric phase NID (AUC, 0.906; p<0.001) and portal phase Z-eff (AUC, 0.947; p<0.001) had the highest accuracy; however, the AUC value was highest when the four parameters are combined (AUC, 0.989; p<0.001; AUC, 0.986; p<0.001; AUC, 0.936; p<0.001; and AUC, 0.986; p<0.001).

CONCLUSION

The present study shows that the combined strategies of four parameters have higher sensitivity and specificity in differentiating CD, UC, and ITB, and may play a key role in guiding treatment.

Comparative transcriptome analysis of T lymphocyte subpopulations and identification of critical regulators defining porcine thymocyte identity

Introduction

The development and migration of T cells in the thymus and peripheral tissues are crucial for maintaining adaptive immunity in mammals. However, the regulatory mechanisms underlying T cell development and thymocyte identity formation in pigs remain largely underexplored.

Method

Here, by integrating bulk and single-cell RNA-sequencing data, we investigated regulatory signatures of porcine thymus and lymph node T cells.

Results

The comparison of T cell subpopulations derived from porcine thymus and lymph nodes revealed that their transcriptomic differences were influenced more by tissue origin than by T cell phenotypes, and that lymph node cells exhibited greater transcriptional diversity than thymocytes. Through weighted gene co-expression network analysis (WGCNA), we identified the key modules and candidate hub genes regulating the heterogeneity of T cell subpopulations. Further, we integrated the porcine thymocyte dataset with peripheral blood mononuclear cell (PBMC) dataset to systematically compare transcriptomic differences between T cell types from different tissues. Based on single-cell datasets, we further identified the key transcription factors (TFs) responsible for maintaining porcine thymocyte identity and unveiled that these TFs coordinately regulated the entire T cell development process. Finally, we performed GWAS of cell type-specific differentially expressed genes (DEGs) and 30 complex traits, and found that the DEGs in thymus-related and peripheral blood-related cell types, especially CD4_SP cluster and CD8-related cluster, were significantly associated with pig productive and reproductive traits.

Discussion

Our findings provide an insight into T cell development and lay a foundation for further exploring the porcine immune system and genetic mechanisms underlying complex traits in pigs.

[Functional outcomes of robot-assisted radical prostatectomy with preservation of pelvic stabilized structure and early elevated retrograde liberation of neurovascular bundle]

Objectives: To examine the functional outcomes of robot-assisted radical prostatectomy (RARP) with preservation of pelvic floor stabilized structure and early elevated retrograde liberation of the neurovascular bundle (PEEL). Methods: This study was a retrospective cohort study. Between June 1, 2022, and March 20, 2023, 27 cases of RARP with PEEL and 153 cases of RARP with preservation of pelvic floor stabilized structure (PPSS) were included in this study. All patients were males, aged (62.5±5.2) years (range: 50 to 73 years). There were 18 cases of ≤T2b stage and 9 cases of T2c stage. After 1∶1 propensity score matching, the postoperative functional outcomes of 27 cases of RARP with PEEL and 27 cases of RARP with PPSS were compared. All surgeries were performed by a single surgeon and included patients were clinically staged as cT1-2N0M0 without preoperative urinary incontinence or erectile dysfunction. In RARP with PEEL, the prostate was cut near the midline at the front when dissecting the neurovascular bundle, dissection was performed between the visceral layer of the pelvic fascia and the prostatic fascia, preserving the parietal layer and the visceral layer of the pelvic fascia, and the neurovascular bundle was retrogradely released from the apex. The cumulative probability curve was plotted using the Kaplan-Meier method and the Log-rank test was used to compare the differences in functional outcomes between the two groups. Univariate and multivariate analysis with the Cox proportional hazards model was used to compare postoperative urinary continence and sexual function. Results: The recovery time of continence and potency was significantly longer in the PPSS group than in the PEEL group (all P<0.05). The continence rate of the PEEL group was significantly higher than that of the PPSS group (92.59% vs. 68.10%, P=0.026) at 3 months after surgery. The potency rate of the PEEL group was also significantly higher than that of the PPSS group (40.70% vs. 15.10%, P=0.037) at 3 months after surgery. In the univariate analysis, compared to the PPSS technique, the PEEL technique was associated with a shorter recovery time of continence (HR=1.94, 95%CI: 1.08 to 3.48, P=0.027) and a shorter recovery time of potency (HR=2.06, 95%CI: 1.03 to 4.13, P=0.042). In the multivariate analysis, the PEEL technique was an independent prognosis factor for postoperative recovery of continence (HR=2.05, 95%CI: 1.01 to 4.17, P=0.047) and potency (HR=3.57, 95%CI: 1.43 to 8.92, P=0.007). All the cases of the PPSS group and the PEEL group were performed successfully with negative surgical margins. Conclusion: Compared with PPSS, PEEL may be more conducive to the recovery of urinary continence and sexual function after RARP.

Saliva biofilm-derived outer membrane vesicles regulate biofilm formation and immune response of oral epithelial cells on titanium surfaces

OBJECTIVES

While the significant roles of outer membrane vesicles (OMVs) from individual oral bacterial species in bacterial-host interactions are known, the involvement of saliva biofilm-derived OMVs in peri-implant disease pathogenesis remains unclear. This study aimed to investigate the effect of saliva biofilm-derived OMVs on regulating saliva biofilm formation and modulating the immune response of the epithelial cells on titanium surfaces.

MATERIALS AND METHODS

Saliva derived biofilms were cultured on tissue culture plates (TCP) for 4 days using pooled saliva from four healthy donors. OMVs secreted from the TCP bound biofilm (referred to as OMVs or healthy saliva biofilm OMVs) were enriched using the size-exclusion chromatography method. We then evaluated the effects of these OMVs on the viability, metabolic activity, and the presence of oral pathogens in saliva biofilm grown on titanium discs for 24 h and 72 h. Furthermore, the impact of OMVs on the mRNA expression and inflammatory cytokines [interleukin (IL)-6, IL-1α, and monocyte chemoattractant protein-1 (MCP-1)] in human oral epithelial cells (OKF6/TERT-2) was investigated using RT-qPCR and enzyme-linked immunosorbent assay (ELISA), respectively.

RESULTS

Healthy saliva biofilm OMVs improved the biomass and activity of saliva biofilm cultured on the titanium surfaces, with inhibited Porphyromonas gingivalis and Fusobacterium nucleatum, and enhanced Streptococcus mutans expression. Additionally, OMVs increased pro-inflammatory cytokine IL-6 mRNA and IL-6 cytokine expression in human oral epithelial cells. However, IL-1α and MCP-1 cytokines were inhibited 24-hour post-incubation with OMVs.

CONCLUSION

Healthy saliva biofilm derived OMVs regulate the activity and pathogen composition of biofilms formed on titanium, while modulating the secretion of pro-inflammation factors of oral epithelial cells grown on titanium surfaces.

CLINICAL RELEVANCE

Healthy saliva biofilm OMVs may regulate the early biofilm formation on abutment surfaces and modulate epithelial cell immune response, which may alter the peri-implant niche and participate in the pathogenesis of peri-implant disease.

Effects of periodontal cells-derived extracellular vesicles on mesenchymal stromal cell function

OBJECTIVE

To enrich and compare three extracellular vesicles-EV subtypes (apoptotic bodies, microvesicles and small EV) from three periodontal cells (periodontal ligament cells-PDLCs, alveolar bone-derived osteoblasts-OBs and gingival fibroblasts-GFs), and assess uptake and cell function changes in buccal fat pad-derived mesenchymal stromal cells (BFP-MSCs).

BACKGROUND

Periodontal cells such as PDLCs, OBs and GFs have the potential to enhance bone and periodontal regeneration, but face significant challenges, such as the regulatory and cost implications of in vitro cell culture and storage. To address these challenges, it is important to explore alternative 'cell-free' strategies, such as extracellular vesicles which have emerged as promising tools in regenerative medicine, to facilitate osteogenic differentiation and bone regeneration.

METHODS AND MATERIALS

Serial centrifuges at 2600 and 16 000 g were used to isolate apoptotic bodies and microvesicles respectively. Small EV-sEV was enriched by our in-house size exclusion chromatography (SEC). The cellular uptake, proliferation, migration and osteogenic/adipogenic differentiation genes were analysed after EVs uptake in BFP-MSCs.

RESULTS

Three EV subtypes were enriched and characterised by morphology, particle size and EV-associated protein expression-CD9. Cellular uptake of the three EVs subtypes was observed in BFP-MSCs for up to 7 days. sEV from the three periodontal cells promoted proliferation, migration and osteogenic gene expression. hOBs-sEV showed superior levels of osteogenesis markers compared to that hPDLCs-sEV and hGFs-sEV, while hOBs-16k EV promoted adipogenic gene expression compared to that from hPDLCs and hGFs.

CONCLUSIONS

Our proof-of-concept data demonstrate that hOBs-sEV might be an alternative cell-free therapeutic for bone tissue engineering.

Microvesicle-eluting nano-engineered implants influence inflammatory response of keratinocytes

Besides enhancing osseo- and soft tissue integration, modulating inflammation at the implant site is also crucial for dental implant success. Uncontrolled peri-implant inflammation can cause significant loss of surrounding tissue and implant failure. It was recently shown that microvesicles (MVs), a less-studied type of extracellular vesicles, play a crucial role in cell-to-cell communication and may modulate angiogenesis and inflammatory response. The effect of MVs on regulating inflammation at an implant site, however, remains unexplored. In the current study, MVs were isolated and characterised from human primary gingival fibroblasts (hGFs) and loaded within titania nanotubes (TNTs, fabricated via anodisation on 3D Ti wire implants) towards their local release. The modified implants were characterised using SEM and confocal imaging to confirm the loading and local release of MVs from TNTs. In vitro studies demonstrated the internalisation of hGFs-MVs by human gingival keratinocytes (OKF6/TERT2 cell line), which caused a significant reduction in the production of pro-inflammatory cytokines. The results support MVs-releasing TNTs as a promising implant surface modification strategy to reduce inflammation, paving the way for further advancements in therapeutic dental implants.

Evaluating models and assessment techniques for understanding oral biofilm complexity

Oral biofilms are three-dimensional (3D) complex entities initiating dental diseases and have been evaluated extensively in the scientific literature using several biofilm models and assessment techniques. The list of biofilm models and assessment techniques may overwhelm a novice biofilm researcher. This narrative review aims to summarize the existing literature on biofilm models and assessment techniques, providing additional information on selecting an appropriate model and corresponding assessment techniques, which may be useful as a guide to the beginner biofilm investigator and as a refresher to experienced researchers. The review addresses previously established 2D models, outlining their advantages and limitations based on the growth environment, availability of nutrients, and the number of bacterial species, while also exploring novel 3D biofilm models. The growth of biofilms on clinically relevant 3D models, particularly melt electrowritten fibrous scaffolds, is discussed with a specific focus that has not been previously reported. Relevant studies on validated oral microcosm models that have recently gaining prominence are summarized. The review analyses the advantages and limitations of biofilm assessment methods, including colony forming unit culture, crystal violet, 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide inner salt assays, confocal microscopy, fluorescence in situ hybridization, scanning electron microscopy, quantitative polymerase chain reaction, and next-generation sequencing. The use of more complex models with advanced assessment methodologies, subject to the availability of equipment/facilities, may help in developing clinically relevant biofilms and answering appropriate research questions.

Engineered adult stem cells: Current clinical trials status of disease treatment

Regenerative medicine is an interdisciplinary field involving the process of replacing and regenerating cells/tissues or organs by integrating medicine, science, and engineering principles to enhance the intrinsic regenerative capacity of the host. Recently, engineered adult stem cells have gained attention for their potential use in regenerative medicine by reducing inflammation and modulating the immune system. This chapter introduces adult stem cell engineering and chimeric antigen receptor T cells (CAR T) gene therapy and summarises current engineered stem cell- and extracellular vesicles (EVs)-focused clinical trial studies that provide the basis for the proposal of a personalised medicine approach to diseases diagnosis and treatment.

Clinical usage of dental stem cells and their derived extracellular vesicles

Stem cell-based therapies remain at the forefront of tissue engineering and regenerative medicine because stem cells are a unique cell source with enormous potential to treat incurable diseases and even extend lifespans. The search for the best stem cell candidates continues to evolve and in recent years, dental stem cells have received significant attention due to their easy accessibility, high plasticity, and multipotential properties. Dental stem cells have been the subject of extensive research in both animal models and human clinical trials over the past two decades, and have demonstrated significant potential in ocular therapy, bone tissue engineering, and, of course, therapeutic applications in dentistry such as regenerative endodontics and periodontal tissue regeneration. These new sources of cells may be advantageous for cellular therapy and the advancement of regenerative medicine strategies, such as allogeneic transplantation or therapy with extracellular vesicles (EVs), which are functional nanoscale membrane vesicles produced by cells. This chapter discusses the accumulating research findings on cell-based regenerative therapy utilizing dental stem cells and their derived EVs, which could be a viable tool for the treatment of a variety of diseases and hence extremely valuable to mankind in the long run.

TNF-αand OSX mRNA of salivary small extracellular vesicles in periodontitis: a pilot study

This cross-sectional study explored extracellular vesicle (EV)-derived gene expression of markers for bone turnover and pro-inflammatory cytokines in periodontal disease. Whole unstimulated saliva was collected from fifty-two participants (18 healthy, 13 gingivitis and 21 stages III/IV periodontitis), from which small extracellular vesicles (sEVs) were enriched using the size-exclusion chromatography (SEC) method, and characterised by morphology, EV-protein, and size distribution, using transmission electron microscopy (TEM), enzyme-linked immunosorbent assay (ELISA), and Nanoparticle Tracking Analysis (NTA), respectively. Bone turnover markers and pro-inflammatory cytokines in salivary sEVs were evaluated using RT-qPCR. Salivary sEVs morphology, mode, size distribution and particle concentration were comparable between healthy, gingivitis, and periodontitis patients. A CD9+ subpopulation was significantly higher in periodontitis-derived salivary sEVs compared to healthy. The detection of sEVs mRNA for osterix (OSX) and tumour necrosis factor-alpha (TNFα) was significantly decreased and increased, respectively, in periodontitis compared to healthy controls, with good discriminatory power for periodontitis diagnosis [area under the curve (AUC) >0.72]. Our study demonstrated that salivary sEVs mRNAs may serve as a potential non-invasive biomarker source for periodontitis diagnosis.

[Preliminary experience of gasless transoral vestibular robotic thyroidectomy]

Objective: To explore the feasibility and safety of the gasless transoral vestibular robotic thyroidectomy using skin suspension. Methods: The clinical data of 20 patients underwent gasless transoral vestibular robotic thyroidectomy in the Department of Otorhinolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University from February 2022 to May 2022 were retrospectively analyzed. Among them, 18 were females and 2 were males, aged (38.7±8.0) years old. The intraoperative blood loss, operation time, postoperative hospital stay, postoperative drainage volume, postoperative pain visual analogue scale (VAS) score, postoperative swallowing function swallowing impairment score-6 (SIS-6), postoperative aesthetic VAS score, postoperative voice handicap index-10 (VHI-10) voice quality, postoperative pathology and complications were recorded. SPSS 25.0 was used for statistical analysis of the data. Results: The operations were successfully completed without conversion to open surgery in all patients. Pathological examination showed papillary thyroid carcinoma in 18 cases, retrosternal nodular goiter in 1 case, and cystic change in goiter in 1 case. The operative time for thyroid cancer was 161.50 (152.75, 182.50) min [M (P₂₅, P₇₅), the same below] and the average operative time for benign thyroid diseases was 166.50 minutes. The intraoperative blood loss 25.00 (21.25, 30.00) ml. In 18 cases of thyroid cancer, the mean diameter of the tumors was (7.22±2.02) mm, and lymph nodes (6.56±2.14) were dissected in the central region, with a lymph node metastasis rate of 61.11%. The postoperative pain VAS score was 3.00 (2.25, 4.00) points at 24 hours, the mean postoperative drainage volume was (118.35±24.32) ml, the postoperative hospital stay was 3.00 (3.00, 3.75) days, the postoperative SIS-6 score was (4.90±1.58) points at 3 months, and the postoperative VHI-10 score was 7.50 (2.00, 11.00) points at 3 months. Seven patients had mild mandibular numbness, 10 patients had mild cervical numbness, and 3 patients had temporary hypothyroidism three months after surgery and 1 patient had skin flap burn, but recovered one month after surgery. All patients were satisfied with the postoperative aesthetic effects, and the postoperative aesthetic VAS score was 10.00 (10.00, 10.00). Conclusion: Gasless transoral vestibular robotic thyroidectomy using skin suspension is a safe and feasible option with good postoperative aesthetic effect, which can provide a new treatment option for some selected patients with thyroid tumors.

Salivary histone deacetylase in periodontal disease: A cross-sectional pilot study

OBJECTIVE

The objective of the study was to profile the expression level of histone deacetylase enzymes (HDACs) in human saliva in periodontal health, gingivitis and periodontitis.

BACKGROUND

HDACs are epigenetic modulators and a group of enzymes that catalyse the removal of acetyl functional groups from the lysine residues of both histone and nonhistone proteins. HDACs have been detected in gingival tissues and may provide valuable insight into the periodontal inflammatory response. However, no studies have investigated the expression of HDACs in saliva from periodontitis-affected individuals and their capacity for periodontal diagnostics and screening.

MATERIALS AND METHODS

Whole unstimulated saliva was collected from 53 participants (17 healthy, 14 gingivitis and 22 stages III/IV periodontitis). The expression of 11 HDACs in saliva samples was determined using RT-qPCR and diagnostic power was calculated using the receiver operating characteristic (ROC) curves and area under the ROC Curve (AUC).

RESULTS

Relative to health, the expression of HDAC4, 8 and 10 was downregulated in gingivitis, and the expression of HDAC4, 6, 8 and 9 was downregulated in periodontitis. Increased HDAC1 and decreased HDAC9 expression were observed in periodontitis compared to gingivitis. Higher HDAC1 and lower HDAC6 and 9 expression was observed in periodontitis compared to non-periodontitis (combining health and gingivitis). Expression of HDAC3, 4, 8, 9 and 10 was significantly decreased in periodontal disease (combining gingivitis and periodontitis) compared to health. HDAC4 and 8 exhibited an excellent diagnostic capacity for distinguishing gingivitis and periodontal disease from health (AUC 0.79-0.86). HDAC9 showed an acceptable power in discriminating periodontitis from health, gingivitis and non-periodontitis (AUC 0.76-0.80). Salivary HDAC enzyme activity showed no significant difference among the groups.

CONCLUSION

This pilot study has demonstrated the differential expression of HDACs in human saliva for the first time and identified HDAC4, 8 and 9 as potential biomarkers in periodontal diagnosis.

Pleiotropic architectures of porcine immune and growth trait pairs revealed by a self-product-based transcriptome method

Pleiotropy is an important biological phenomenon with complicated genetic architectures for multiple traits. To date, pleiotropy has been mainly identified by multi-trait genome-wide association studies, but this method has its disadvantages, and new developments for pleiotropy detection methods are needed. Here we define a novel metric, self-product, to measure individual-level co-variation of two traits, and develop a novel self-product-based transcriptome method to detect pleiotropic genes (PGs). Our method was tested using four immune-growth trait pairs and four immune-immune trait pairs in pigs. Comparative transcriptome analyses identified hundreds of candidate PGs related to eight trait pairs from two tails of self-product distribution. Gene Ontology enrichment analysis indicated that most of identified PGs were involved in immune- or growth-related biological processes. We established PG interaction networks to exhibit core genes shared by eight trait pairs, of which CCL5 and IL-10 genes were the hub genes. Genetic association analyses showed that SmaI-polymorphisms of CCL5 and IL-10 genes had significant associations with phenotypic co-variations of multiple trait pairs, indicating that the variants in pleiotropic genes were also pleiotropic variants. Taken together, the validity of our proposed method was preliminarily verified, and our findings provide new insights into the genetic basis of pleiotropic architectures of immune and growth trait pairs in pigs.

Emerging Technologies of Three-Dimensional Printing and Mobile Health in COVID-19 Immunity and Regenerative Dentistry

The ongoing coronavirus disease 2019 (COVID-19) pandemic highlights the importance of developing point-of-care (POC) antibody tests for monitoring the COVID-19 immune response upon viral infection or following vaccination, which requires three key aspects to achieve optimal monitoring, including three-dimensional (3D)-printed POC devices, mobile health (mHealth), and noninvasive sampling. As a critical tissue engineering concept, additive manufacturing (AM, also known as 3D printing) enables accurate control over the dimensional and architectural features of the devices. mHealth refers to the use of portable digital devices, such as smartphones, tablet computers, and fitness and medical wearables, to support health, which facilitates contact tracing, and telehealth consultations during the pandemic. Compared with invasive biosample (blood), saliva is of great importance in the spread and surveillance of COVID-19 as a noninvasive diagnostic method for virus detection and immune status monitoring. However, investigations into 3D-printed POC antibody test and mHealth using noninvasive saliva are relatively limited. Further exploration of 3D-printed antibody POC tests and mHealth applications to monitor antibody production for either disease onset or immune response following vaccination is warranted. This review briefly describes the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus and immune response after infection and vaccination, then discusses current widely used binding antibody tests using blood samples and enzyme-linked immunosorbent assays on two-dimensional microplates before focusing upon emerging POC technological platforms, such as field-effect transistor biosensors, lateral flow assay, microfluidics, and AM for fabricating immunoassays, and the possibility of their combination with mHealth. This review proposes that noninvasive biofluid sampling combined with 3D POC antibody tests and mHealth technologies is a promising and novel approach for POC detection and surveillance of SARS-CoV-2 immune response. Furthermore, as key concepts in dentistry, the application of 3D printing and mHealth was also included to facilitate the appreciation of cutting edge techniques in regenerative dentistry. This review highlights the potential of 3D printing and mHealth in both COVID-19 immunity monitoring and regenerative dentistry.

Synthesis of a Healthy Sweetener d-Tagatose from Starch Catalyzed by Semiartificial Cell Factories

d-Tagatose is one of the several healthy sweeteners that can be a substitute for sucrose and fructose in our daily life. Whole cell-catalyzed phosphorylation and dephosphorylation previously reported by our group afford a thermodynamic-driven strategy to achieve tagatose production directly from starch with high product yields. Nonetheless, the poor structural stability of cells and difficulty in biocatalyst recycling restrict its practical application. Herein, an efficient and stable semiartificial cell factory (SACF) was developed by constructing an organosilica network (OSN) artificial shell on the cells bearing five thermophilic enzymes to produce tagatose. The OSN artificial shell, the thickness of which can be regulated by changing the tetraethyl silicate concentration, exhibited tunable permeability and superior mechanical strength. In contrast with cells, SACFs showed a relative activity of 99.5% and an extended half-life from 33.3 to 57.8 h. Over 50% of initial activity was retained after 20 reuses. The SACFs can catalyze seven consecutive reactions with tagatose yields of over 40.7% in field applications.

Fabrication and characterization of a 3D polymicrobial microcosm biofilm model using melt electrowritten scaffolds

The majority of current biofilm models or substrates are two-dimensional (2D) and support biofilm growth in the horizontal plane only. Three-dimensional (3D) substrates may support both horizontal and vertical biofilm growth. This study compared biofilm growth quantity and quality between highly porous 3D micrometric fibrous scaffolds and 2D film substrates fabricated from medical grade polycaprolactone (mPCL). Melt electrowriting (MEW), a high-resolution additive manufacturing technology, was employed to design orderly aligned fine (~12 μm) fibre-based 3D scaffolds, while 2D films were fabricated by a casting method. The 3D scaffolds with a controlled pore size of 100 and 250 μm and thickness of ~0.8 mm and 2D films were incubated in pooled saliva collected from six volunteers for 1, 2, 4, 7 and 10 days at 37 °C to facilitate polymicrobial biofilm formation. Crystal violet assay demonstrated greater biofilm biomass in 3D MEW scaffolds than in 2D films. Biofilm thickness in 3D scaffolds was significantly higher compared to the biofilm thickness in 2D films. Both biovolume and substratum coverage of the biofilms was higher in the 3D scaffolds compared to 2D films. Polymeric bridges, pores, and channels characteristic of biofilms could be demonstrated by scanning electron microscopy. 16S rRNA sequencing demonstrated that the polymicrobial biofilms in the 3D scaffolds were able to retain 60-70 % of the original inoculum microbiome after 4 days. The MEW-fabricated 3D fibrous scaffold is a promising substrate for supporting multidirectional biofilm growth and modelling of a polymicrobial microcosm.

Saliva Diagnosis Using Small Extracellular Vesicles and Salivaomics

Saliva is a complex oral biofluid composed of various biological molecules secreted by major and minor salivary glands, as well as by-products of host oral cells, oral bacteria, small extracellular vesicles (sEVs), and gingival crevicular fluid. Recently, salivary small extracellular vesicles and salivary multi-omics (microbiome, transcriptome, DNA methylome and proteome) are emerging as potential diagnostic tools for oral diseases, including the highly prevalent periodontitis. Here, we describe the methodologies for how to isolate salivary sEVs using the size exclusion chromatography method, and how to perform salivaomics, which may guide future dental research.

Antibody response to BNT162b2 mRNA vaccine in gingival crevicular fluid

BACKGROUND

This prospective cohort study aimed to evaluate the antibody responses in non-invasive gingival crevicular fluid (GCF) and unstimulated whole saliva to the SARS-CoV-2 Spike unit 1 receptor-binding domain (S1-RBD) protein following administration of the mRNA BNT162b2 vaccine.

METHODS

This longitudinal study recruited 37 participants with no prior COVID-19 exposure (eight people recruited prior to the COVID-19 pandemic - labeled pre-COVID, 16 vaccinated and 13 non-vaccinated participants). An enzyme-linked immunosorbent assay (ELISA) was used to determine antibody levels against S1-RBD in saliva (n=90) and GCF (n=80) samples obtained at 1 and 3 weeks after dose 1, and 3 days, 7 days, and 3 weeks after dose 2. To determine previous SARS-CoV-2 infection status, anti-nucleocapsid (N) Ig levels were determined in samples from the pre-COVID (saliva as reference), non-vaccinated (saliva and GCF), and vaccinated (saliva and GCF) participants at 1-week post-dose 1 using ELISA.

RESULTS

Salivary levels of anti-N antibodies measured in samples from vaccinated and nonvaccinated participants were comparable to those in pre-COVID saliva samples collected between October 2018 and September 2019, thus confirming that all study participants had no prior SARS-CoV-2 infection. Overall, the levels of anti-S1-RBD antibodies peaked at 3 weeks after dose 2 in both saliva and GCF for all three immunoglobulin isotypes. Notably, the concentration of anti-S1-RBD antibodies in GCF was significantly higher than in saliva at all time points.

CONCLUSION

This study establishes GCF and saliva as viable alternative non-invasive sources to monitor levels of antibodies following vaccination, with GCF demonstrating feasibility as a biofluid source for the detection of antibodies against SARS-CoV-2 S1-RBD antigen.

The Relevance of DNA Methylation and Histone Modification in Periodontitis: A Scoping Review

Background: Periodontitis is a chronic inflammatory disease involving an interplay between bacteria, inflammation, host response genes, and environmental factors. The manifestation of epigenetic factors during periodontitis pathogenesis and periodontal inflammation is still not well understood, with limited reviews on histone modification with periodontitis management. This scoping review aims to evaluate current evidence of global and specific DNA methylation and histone modification in periodontitis and discuss the gaps and implications for future research and clinical practice. Methods: A scoping literature search of three electronic databases was performed in SCOPUS, MEDLINE (PubMed) and EMBASE. As epigenetics in periodontitis is an emerging research field, a scoping review was conducted to identify the extent of studies available and describe the overall context and applicability of these results. Results: Overall, 30 studies were evaluated, and the findings confirmed that epigenetic changes in periodontitis comprise specific modifications to DNA methylation patterns and histone proteins modification, which can either dampen or promote the inflammatory response to bacterial challenge. Conclusions: The plasticity of epigenetic modifications has implications for the future development of targeted epi-drugs and diagnostic tools in periodontitis. Such advances could be invaluable for the early detection and monitoring of susceptible individuals.

3D bioprinted extracellular vesicles for tissue engineering - a perspective

Harnessing three-dimensional (3D) bioprinted extracellular vesicles (EVs) holds great promise to advance the fields of tissue engineering and regenerative medicine. EVs are naturally occurring biological nanoparticles that are emerging as powerful 'cell-free' nanotherapeutics characterised by a cargo of protein, lipids, or genetic material that can be delivered to recipient cells. Conventional 3D bioprinting utilises bioinks, a mixture of biomaterial and live cells, to fabricate 3D constructs for tissue regeneration purposes. The utilization of EVs instead of living cells for bioprinting may achieve targeted EV delivery, thus addressing a key challenge of EVs application in tissue engineering, as well as overcoming the regulatory and cost-effectiveness issues of using live cells. Given that 3D bioprinted EVs combine the regenerative capabilities of both bioprinting and EVs, this perspective explores the existing literature reporting their applications in tissue engineering, which target angiogenesis, osteogenesis, chondrogenesis, myogenesis, and carcinoprevention. Technical challenges and future trends for 3D bioprinted EVs in biofabrication and tissue engineering are examined. Ultimately, a personalised bioprinted EVs concept and a workflow for future bioprinted EVs studies focussed on clinical translation are proposed.

Atractylenolide I inhibited the development of malignant colorectal cancer cells and enhanced oxaliplatin sensitivity through the PDK1-FoxO1 axis

BACKGROUND

Colorectal cancer (CRC) is a type of ordinary malignancy of the gastrointestinal tract. Atractylenolide I (AT-I) has been shown to inhibit the process of CRC. However, the specific mechanism by which AT-I inhibits CRC is not yet well understood.

METHODS

Cell Counting Kit-8 and colony formation assays were conducted to examine cell proliferation. The cell apoptosis was detected by terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling (TUNEL). Cell invasion and migration were evaluated by wound-healing and Transwell assay. The angiogenesis capabilities of the cells were examined by tube formation experiments. Western blot was conducted to examine the apoptosis and angiogenesis-associated proteins, pyruvate dehydrogenase kinase 1 (PDK1), and Forkhead box protein O1 (FoxO1) expression.

RESULTS

We found that AT-I inhibited the proliferative, migratory and invasive abilities of Human colorectal cancer cell line HCT116 cells but stimulated cell death by promoting cell apoptosis via the PDK1/FoxO1 axis. In addition, the upregulation of PDK1 decreased the inhibitory effect of AT-I on HCT116 angiogenesis, and AT-I increased oxaliplatin sensitivity via the PDK1/FoxO1 axis.

CONCLUSIONS

Collectively, AT-I inhibited the malignant development of CRC cells and increased oxaliplatin sensitivity by decreasing PDK1 and inhibiting FoxO1 phosphorylation. Thus, AT-I has protective potential and could be a promising agent for CRC treatment.

[Preliminary experience of robotic lateral neck dissection via combined axillary-retroauricular approach for N1b papillary thyroid carcinoma]

Objective: To evaluate the feasibility, safety, and short-term efficacy of robotic lateral neck dissection via combined axillary-retroauricular approach for N1b papillary thyroid carcinoma (PTC). Methods: Thirty patients with cT1-2N1bM0 PTC who received robotic lateral neck dissection via combined axillary-retroauricular approach were included in the Department of Otorhinolaryngology of Sun Yat-sen Memorial Hospital from December 2016 to December 2020. There were 10 males and 20 females, with a median age of 34.5 years and a median body mass index of 25.55 kg/m². The clinical, surgical, complications, pathology and follow-up data were analysed with SPSS 25.0 software package. Results: The median operative time of 30 patients was 255.50 min, the median operative blood loss was 69.00 ml, and the median postoperative hospital stay was 6.00 days. The incidence of postoperative temporary recurrent laryngeal nerve paralysis was 3.33% (1/30), temporary hypoparathyroidism was 16.67%(5/30), temporary accessory nerve injury was 3.33% (1/30), hematoma was 3.33% (1/30) and chylous leakage was 3.33% (1/30). The median visual analogue scale (VAS) score was 8.00, and the follow-up time was 13-38 months, with a median of 25.5 months. One case showed cervical lymph node recurrence 14 months after surgery. The most recent dynamic recurrence risk stratification showed 21 patients (70.00%) had excellent responses. Conclusions: Robotic lateral neck dissection via combined axillary-retroauricular approach for unilateral cN1b PTC is safe, feasible and aesthetic. The short-term efficacy and dynamic recurrence risk stratification results of short-term follow-up are satisfactory. It can provide a surgical option for cN1b PTC patients.

The role of booster vaccination and ongoing viral evolution in seasonal circulation of SARS-CoV-2

Periodic resurgences of COVID-19 in the coming years can be expected, while public health interventions may be able to reduce their intensity. We used a transmission model to assess how the use of booster doses and non-pharmaceutical interventions (NPIs) amid ongoing pathogen evolution might influence future transmission waves. We find that incidence is likely to increase as NPIs relax, with a second seasonally driven surge expected in autumn 2022. However, booster doses can greatly reduce the intensity of both waves and reduce cumulative deaths by 20% between 7 January 2022 and 7 January 2023. Reintroducing NPIs during the autumn as incidence begins to increase again could also be impactful. Combining boosters and NPIs results in a 30% decrease in cumulative deaths, with potential for greater impacts if variant-adapted boosters are used. Reintroducing these NPIs in autumn 2022 as transmission rates increase provides similar benefits to sustaining NPIs indefinitely (307 000 deaths with indefinite NPIs and boosters compared with 304 000 deaths with transient NPIs and boosters). If novel variants with increased transmissibility or immune escape emerge, deaths will be higher, but vaccination and NPIs are expected to remain effective tools to decrease both cumulative and peak health system burden, providing proportionally similar relative impacts.

LiCl-induced immunomodulatory periodontal regeneration via the activation of the Wnt/β-catenin signaling pathway

Background

Growing evidence suggests that excessive inflammation hampers the regenerative capacity of periodontal ligament cells (PDLCs) and that activation of the Wnt/β‐catenin pathway is crucial in suppressing immune dysregulation.

Objective

This study aimed to establish the role of the Wnt/β‐catenin in regulating the immune microenvironment and its subsequent impact on periodontal regeneration.

Methods

Lithium chloride (LiCl, Wnt activator) was administered daily into the standard periodontal defects created in 12‐week‐old Lewis rats. Harvested at 1‐week and 2‐week post‐surgery, samples were then subjected to histological and immunohistochemical evaluation of macrophage distribution and phenotype (pro‐inflammatory M1 and anti‐inflammatory M2). A murine macrophage cell line, RAW 264.7, was stimulated with LiCl to activate Wnt/β‐catenin. Following treatment with the conditioned medium derived from the LiCl‐activated macrophages, the expression of bone‐ and cementum‐related markers of the PDLCs was determined. The involvement of Wnt/β‐catenin in the immunoregulation and autophagic activity was further investigated with the addition of cardamonin, a commercially available Wnt inhibitor.

Results

A significantly increased number of macrophages were detected around the defects during early healing upon receiving the Wnt/β‐catenin signaling cue. The defect sites in week 2 exhibited fewer M1 and more M2 macrophages along with an enhanced regeneration of alveolar bone and cementum in the Wnt/β‐catenin activation group. LiCl‐induced immunomodulatory effect was accompanied with the activation Wnt/β‐catenin signaling, which was suppressed in the presence of Wnt inhibitor. Exposure to LiCl could induce autophagy in a dose‐dependent manner, thus maintaining macrophages in a regulatory state. The expression level of bone‐ and cementum‐related markers was significantly elevated in PDLCs stimulated with LiCl‐activated macrophages.

Conclusion

The application of Wnt activator LiCl facilitates the recruitment of macrophages to defect sites and regulates their phenotypic switching in favor of periodontal regeneration. Suppression of Wnt/β‐catenin pathway could attenuate the LiCl‐induced immunomodulatory effect. Taken together, the Wnt/β‐catenin pathway may be targeted for therapeutic interventions in periodontal diseases.

[Differential diagnosis of gallbladder polypoid lesions by micro-flow imaging]

OBJECTIVE

To explore the value of micro-flow imaging (MFI) in evaluating blood flow characteristics and differential diagnosis of gallbladder polypoid lesions.

METHODS

We retrospectively analyzed the clinical data and ultrasound images of 73 patients with gallbladder polypoid lesions, including 24 patients with pathologically confirmed neoplastic polyps (n=24) and 49 with non-neoplastic polyps (n=49). All the patients underwent conventional ultrasound, MFI and contrast enhanced ultrasound (CEUS) before cholecystectomy. The blood flow characteristics of the lesions in color Doppler flow imaging (CDFI) and MFI were compared, and the consistency of the findings by these two modalities with those of CEUS were evaluated by weighted Kappa consistency test. The diagnostic performance of MFI for gallbladder polypoid lesions was assessed.

RESULTS

There were significant differences between MFI and CDFI in the evaluation of blood flow characteristics of gallbladder polypoid lesions (χ²=37.684, P < 0.001). MFI showed better performance than CDFI in displaying the blood flow characteristics of the polyps. The consistency in the findings was 0.118 between CDFI and CEUS and 0.816 between MFI and CEUS. The sensitivity, specificity and accuracy of MFI in distinguishing neoplastic polyps from non-neoplastic polyps were 75.00%, 93.88% and 87.67%, respectively.

CONCLUSION

MFI has a good consistency with CEUS in displaying the blood flow characteristics of gallbladder polypoid lesions and can accurately distinguish neoplastic polyps from non-neoplastic polyps, thus providing new ultrasound diagnostic evidence to support clinical decisions on optimal treatments of gallbladder polypoid lesions.

[Progress in the study of antiviral activity of cepharanthine against SARS-CoV-2]

As a member of the dibenzyl isoquinoline alkaloid family, cepharathine is an alkaloid from the traditional Chinese medicine cepharathine, which is mainly used for treatment of leukopenia and other diseases. Recent studies of the inhibitory effect of cepharathine against SARS-CoV-2 have attracted widespread attention and aroused heated discussion. As the original discoverer of the anti-SARS-CoV-2 activity of cepharanthine, here we briefly summarize the discovery of cepharanthine and review important progress in relevant studies concerning the discovery and validation of anti-SARS-CoV-2 activity of cepharathine, its antiviral mechanisms and clinical trials of its applications in COVID-19 therapy.

AB0058 SERUM ANTIGENOME PROFILING REVEALS DIAGNOSTIC MODELS FOR RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is a chronic autoimmune disease that leads to joint damage, systemic inflammation and early mortality. Though the precise molecular mechanism in the triggering immune response are not fully understood, the emergence of antibodies against self-antigens can serve as diagnostic biomarker. Multiple antigens have been confirmed. However, the profiling of serum antigen, antigenome, remains poorly known.

Objectives

The study aimed to investigate the serum antigenomic profiling and determine potential diagnostic biomarkers using label-free proteomic technology implemented with machine-learning algorithm.

Methods

We captured serum antigens from a cohort consisting of 60 RA patients (45 ACPA-positive RA patients and 15 ACPA-negative RA patients), sex- and age-matched 30 osteoarthritis patients and 30 healthy controls. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed. We then trained a machine learning model to classify RA, ACPA-positive RA and ACPA-negative RA based on proteomic data and validated in the cohort.

Results

We identified 62, 71 and 49 differentially expressed proteins (DEPs) in RA, ACPA-positive RA and ACPA-negative RA respectively, compared to OA and healthy controls. Among these DEPs, the pathway enrichment analysis and protein-protein interactions networks were conducted. Three panels were constructed to classify RA, ACPA-positive RA and ACPA-negative RA using random forest models algorithm based on the molecular signature of DEPs, whose area under curve (AUC) were calculated as 0.9949 (95% CI = 0.9792-1), 0.9913 (95%CI = 0.9653-1) and 1.0 (95% CI = 1-1).

Conclusion

This study presented serum antigen profiling of RA. Among them, three panels of antigens were identified to classify RA, ACPA-positive and ACPA-negative RA patients as diagnostic biomarkers.

References

[1]Smolen JS, Aletaha D, McInnes IB. Rheumatoid arthritis. Lancet (London, England). (2016) 388: 2023-38. doi: 10.1016/S0140-6736(16)30173-8

[2]De Rycke L, Peene I, Hoffman IE, Kruithof E, Union A, Meheus L, et al. Rheumatoid factor and anticitrullinated protein antibodies in rheumatoid arthritis: diagnostic value, associations with radiological progression rate, and extra-articular manifestations. Ann Rheum Dis. (2004) 63: 1587-93. doi: 10.1136/ard.2003.017574

[3]Kampstra ASB, Dekkers JS, Volkov M, Dorjée AL, Hafkenscheid L, Kempers AC, et al. Different classes of anti-modified protein antibodies are induced on exposure to antigens expressing only one type of modification. Ann Rheum Dis. (2019) 78: 908-16. doi: 10.1136/annrheumdis-2018-214950

[4]Liao W, Li Z, Li T, Zhang Q, Zhang H, Wang X. Proteomic analysis of synovial fluid in osteoarthritis using swath‑mass spectrometry. Mol Med Rep. (2018) 17: 2827-36. doi: 10.3892/mmr.2017.8250

[5]Peffers MJ, Smagul A, Anderson JR. Proteomic analysis of synovial fluid: current and potential uses to improve clinical outcomes. Expert Rev Proteomic. (2019) 16: 287-302. doi:10.1080/14789450.2019.1578214

[6]Swan AL, Mobasheri A, Allaway D, Liddell S, Bacardit J. Application of machine learning to proteomics data: classification and biomarker identification in postgenomics biology. Omics: a journal of integrative biology. (2013) 17: 595-610. doi: 10.1089/omi.2013.0017

[7]Mahler M, Martinez-Prat L, Sparks JA, Deane KD. Precision medicine in the care of rheumatoid arthritis: focus on prediction and prevention of future clinically-apparent disease. Autoimmun Rev. (2020) 19: 102506. doi: 10.1016/j.autrev.2020.102506

[8]Mun S, Lee J, Park A, Kim HJ, Lee YJ, Son H, et al. Proteomics approach for the discovery of rheumatoid arthritis biomarkers using mass spectrometry. Int J Mol Sci. (2019) 20. doi: 10.3390/ijms20184368

[9]Li K, Mo W, Wu L, Wu X, Luo C, Xiao X, et al. Novel autoantibodies identified in acpa-negative rheumatoid arthritis. Ann Rheum Dis. (2021). doi: 10.1136/annrheumdis-2020-218460

Figure 1.

Study overview and antigenome characterization

Disclosure of Interests

None declared

Simulated and clinical aerosol spread in common periodontal aerosol-generating procedures

Objectives

This study evaluated particle spread associated with various common periodontal aerosol-generating procedures (AGPs) in simulated and clinical settings.

Materials and methods

A simulation study visualized the aerosols, droplets, and splatter spread with and without high-volume suction (HVS, 325 L/min) during common dental AGPs, namely ultrasonic scaling, air flow prophylaxis, and implant drilling after fluorescein dye was added to the water irrigant as a tracer. Each procedure was repeated 10 times. A complementary clinical study measured the spread of contaminated particles within the dental operatory and quantified airborne protein dispersion following 10 min of ultrasonic supragingival scaling of 19 participants during routine periodontal treatment.

Results

The simulation study data showed that air flow produced the highest amount of splatters and the ultrasonic scaler generated the most aerosol and droplet particles at 1.2 m away from the source. The use of HVS effectively reduced 37.5–96% of splatter generation for all three dental AGPs, as well as 82–93% of aerosol and droplet particles at 1.2 m for the ultrasonic scaler and air polisher. In the clinical study, higher protein levels above background levels following ultrasonic supragingival scaling were detected in fewer than 20% of patients, indicating minimal particle spread.

Conclusions

While three common periodontal AGPs produce aerosols and droplet particles up to at least 1.2 m from the source, the use of HVS is of significant benefit. Routine ultrasonic supragingival scaling produced few detectable traces of salivary protein at various sites throughout the 10-min dental operatory.

Clinical relevance

The likelihood of aerosol spread to distant sites during common periodontal AGPs is greatly reduced by high-volume suction. Clinically, limited evidence of protein contaminants was found following routine ultrasonic scaling, suggesting that the the majority of the contamination consisits of the irrigant rather than organic matter from the oral cavity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00784-022-04532-8.

[Transoral robotic nasopharyngectomy for local recurrent nasopharyngeal carcinoma]

Objective: To investigate the safety, efficacy, locally control and survival results of transoral Da Vinci robotic surgery for salvage treatment of locally recurrent nasopharyngeal carcinoma. Methods: This retrospective study included 33 patients with locally recurrent nasopharyngeal carcinoma (stage rT1-2, partial rT3) underwent transoral Da Vinci robotic surgery between October 2017 and January 2020. There were 20 males and 11 females, with an average age of (47.9±10.5) years. The lesions were localized in nasopharyngeal cavity in 14 cases, with extending to parapharyngeal space in 6 cases and the floor of sphenoid sinus in 13 cases. Transnasal endoscopy was used to assist surgery if necessary. SPSS 25.0 statistical software was used for statistical analysis. Results: Transoral robotic nasopharyngectomy was successfully performed in all cases without conversion to open surgery, of which 13 cases were combined with transnasal endoscopic surgery. The average operation time was (126.2±30.0) min, ranging from 90 to 180 min. The postoperative pathological margin was R0 (31 cases) and R1 (2 cases), with no tumor residue. Complications of surgery mainly included symptoms of headache, nasal dryness and velopharyngeal insufficiency without nasopharyngeal hemorrhage. Follow-up time was from 3 to 54 months. One case had tumor recurrence 11 months after operation, 1 case had ipsilateral cervical lymph node metastasis 27 months after operation, 2 cases had distant metastasis and 1 case died of nasopharyngeal hemorrhage 3 months after operation. The 1-year, 2-year and 3-year overall survival rates were 97.0%, 96.0% and 92.9%, respectively and the local recurrence free rates were 97.0%, 95.7% and 91.7%, respectively. Conclusion: Transoral robotic nasopharyngectomy is safe and feasible for local recurrent nasopharyngeal carcinoma in selected patients, with higher local control rate and quality of life.

Genome-Wide Association Study and FST Analysis Reveal Four Quantitative Trait Loci and Six Candidate Genes for Meat Color in Pigs

Meat color is the primary criterion by which consumers evaluate meat quality. However, there are a few candidate genes and molecular markers of meat color that were reported for pig molecular breeding. The purpose of the present study is to identify the candidate genes affecting meat color and provide the theoretical basis for meat color molecular breeding. A total of 306 Suhuai pigs were slaughtered, and meat color was evaluated at 45 min and 24 h after slaughter by CIELAB color space. All individuals were genotyped using GeneSeek GGP-Porcine 80K SNP BeadChip. The genomic estimated breeding values (GEBVs), heritability, and genetic correlation of meat color were calculated by DMU software. The genome-wide association studies (GWASs) and the fixation index (F_ST) tests were performed to identify SNPs related to meat color, and the candidate genes within 1 Mb upstream and downstream of significant SNPs were screened by functional enrichment analysis. The heritability of L* 45 min, L* 24 h, a* 45 min, a* 24 h, b* 45 min, and b* 24 h was 0.20, 0.16, 0.30, 0.13, 0.29, and 0.22, respectively. The genetic correlation between a* (a* 45 min and a* 24 h) and L* (L* 45 min and L* 24 h) is strong, whereas the genetic correlation between b* 45 min and b* 24 h is weak. Forty-nine significant SNPs associated with meat color were identified through GWAS and F_ST tests. Among these SNPs, 34 SNPs were associated with L* 45 min within a 5-Mb region on Sus scrofa chromosome 11 (SSC11); 22 SNPs were associated with a* 45 min within a 14.72-Mb region on SSC16; six SNPs were associated with b* 45 min within a 4.22-Mb region on SSC13; 11 SNPs were associated with b* 24 h within a 2.12-Mb region on SSC3. These regions did not overlap with meat color–associated QTLs reported previously. Moreover, six candidate genes (HOMER1, PIK3CG, PIK3CA, VCAN, FABP3, and FKBP1B), functionally related to muscle development, phosphatidylinositol phosphorylation, and lipid binding, were detected around these significant SNPs. Taken together, our results provide a set of potential molecular markers for the genetic improvement of meat color in pigs.

Scaffold geometry modulation of mechanotransduction and its influence on epigenetics

The dynamics of cell mechanics and epigenetic signatures direct cell behaviour and fate, thus influencing regenerative outcomes. In recent years, the utilisation of 2D geometric (i.e. square, circle, hexagon, triangle or round-shaped) substrates for investigating cell mechanics in response to the extracellular microenvironment have gained increasing interest in regenerative medicine due to their tunable physicochemical properties. In contrast, there is relatively limited knowledge of cell mechanobiology and epigenetics in the context of 3D biomaterial matrices, i.e., hydrogels and scaffolds. Scaffold geometry provides biophysical signals that trigger a nucleus response (regulation of gene expression) and modulates cell behaviour and function. In this review, we explore the potential of additive manufacturing to incorporate multi length-scale geometry features on a scaffold. Then, we discuss how scaffold geometry direct cell and nuclear mechanosensing. We further discuss how cell epigenetics, particularly DNA/histone methylation and histone acetylation, are modulated by scaffold features that lead to specific gene expression and ultimately influence the outcome of tissue regeneration. Overall, we highlight that geometry of different magnitude scales can facilitate the assembly of cells and multicellular tissues into desired functional architectures through the mechanotransduction pathway. Moving forward, the challenge confronting biomedical engineers is the distillation of the vast knowledge to incorporate multiscaled geometrical features that would collectively elicit a favourable tissue regeneration response by harnessing the design flexibility of additive manufacturing. STATEMENT OF SIGNIFICANCE: It is well-established that cells sense and respond to their 2D geometric microenvironment by transmitting extracellular physiochemical forces through the cytoskeleton and biochemical signalling to the nucleus, facilitating epigenetic changes such as DNA methylation, histone acetylation, and microRNA expression. In this context, the current review presents a unique perspective and highlights the importance of 3D architectures (dimensionality and geometries) on cell and nuclear mechanics and epigenetics. Insight into current challenges around the study of mechanobiology and epigenetics utilising additively manufactured 3D scaffold geometries will progress biomaterials research in this space.

Association between Sleep Duration and Mild Cognitive Impairment at Different Levels of Metabolic Disease in Community-Dwelling Older Chinese Adults

OBJECTIVES

The purpose of this study was to investigate the relationship between metabolic syndrome (MetS), sleep duration and mild cognitive impairment (MCI) in community-dwelling older Chinese adults.

METHODS

The study comprised of 1367 community-dwelling Chinese participants (563 men; mean age: 71.0 years) recruited from Tianjin and Shanghai, China who were invited to participate in a comprehensive geriatric assessment. The International Diabetes Federation metabolic syndrome guidelines were used to define MetS. The Mini-Mental State Examination (MMSE) and the Instrumental Activities of Daily Living (IADL) scale were used for the initial classification of patients with MCI. We divided sleep duration into five groups (≤6 h, 6-8 h which was used as the reference, 8-9 h, 9-10 h, and >10 h). Nutritional status was assessed by Mini Nutrition Assessment Short Form.

RESULTS

The overall incidence of metabolic syndrome was 46.7%, the overall incidence of mild cognitive impairment was 17.4%. In logistic regression analysis model, after adjusting for multiple confounding factors such as nutritional status and physical activity level, there was a significant positive association between long sleep duration (> 10h) and mild cognitive impairment in general population and metabolic syndrome population (p<0.05), but the association was not significant in non-metabolic syndrome group. In addition, in the long sleep duration group, the components of metabolic syndrome, elevated blood glucose were significantly associated with mild cognitive impairment (p<0.05).

CONCLUSIONS

Long sleep duration was significantly associated with increased risk of MCI in older adults with MetS, but not in those without MetS. The prevention of MCI may be more effective in the population of MetS with long sleep duration.

Mediating Effects of Malnutrition on the Relationship between Depressive Symptoms Clusters and Muscle Function Rather than Muscle Mass in Older Hemodialysis Patients

OBJECTIVES

The purpose of this study was to investigate the association and mediation pathways among muscle mass, muscle function (muscle strength and physical performance), and malnutrition with depressive symptoms clusters in the older hemodialysis patients.

DESIGN

A multi-center cross-sectional study.

SETTING AND PARTICIPANTS

A total of 499 patients aged ≥ 60 on hemodialysis from seven facilities in Shanghai of China from 2020 to 2021.

MEASUREMENTS

Muscle mass was assessed by skeletal muscle index(SMI). Muscle strength was measured by handgrip strength, and physical performance was measured via gait speed and Timed Up and Go Test (TUGT). Nutritional status was assessed by Malnutrition Inflammation Score (MIS). Depressive symptoms were evaluated by the Patient Health Questionnaire-9 (PHQ-9). Logistic regression and mediation analyses fully adjusted for all potential confounding factors.

RESULTS

Among 499 participants (312 men, mean age 69.2±6.6 years), 108 (21.6%) had depressive symptoms. The muscle strength, physical performance and malnutrition were associated with depressive symptoms. Furthermore, malnutrition significantly mediated the association of muscle function with total, cognitive-affective symptoms. The association of the muscle function with somatic symptoms were mediated by the nutritional status. The mediated proportions of malnutrition in the relationship between physical performance and depressive symptoms clusters were stronger in somatic symptoms than in cognitive-affective symptoms.

CONCLUSIONS

Our findings suggest that muscle function rather than muscle mass may contribute substantially to the development of depressive symptoms clusters in the hemodialysis via malnutrition. The malnutrition mediated stronger in the association of muscle function with somatic symptoms. These findings may help guide clinicians to better diagnose and manage depression in the context of concomitant muscle function and malnutrition.

Salivary SARS-CoV-2 antibody detection using S1-RBD protein-immobilized 3D melt electrowritten poly(ε-caprolactone) scaffolds

Sensitive detection of immunoglobulin antibodies against SARS-CoV-2 during the COVID-19 pandemic is critical to monitor the adaptive immune response after BNT162b2 mRNA vaccination. Currently employed binding antibody detection tests using 2D microplate-based enzyme-linked immunosorbent assays (ELISA) are limited by the degree of sensitivity. In this study, a 3D antibody test was developed by immobilizing the receptor-binding domain on Spike subunit 1 (S1-RBD) of SARS-CoV-2 onto engineered melt electrowritten (MEW) poly(ε-caprolactone) (PCL) scaffolds (pore: 500 μm, fiber diameter: 17 μm) using carbodiimide crosslinker chemistry. Protein immobilization was confirmed using X-ray photoelectron spectroscopy (XPS) by the presence of peaks corresponding with nitrogen. Self-developed indirect ELISA was performed to assess the functionality of the 3D platform in comparison with a standard 2D tissue culture plate (TCP) system, using whole unstimulated saliva samples from 14 non-vaccinated and 20 vaccinated participants (1- and 3- weeks post-dose 1; 3 days, 1 week and 3 weeks post-dose 2) without prior SARS-CoV-2 infection. The three-dimensional S1-RBD PCL scaffolds, while demonstrating a kinetic trend comparable to 2D TCP, exhibited significantly higher sensitivity and detection levels for all three immunoglobulins assayed (IgG, IgM, and IgA). These novel findings highlight the potential of MEW PCL constructs in the development of improved low-cost, point-of-care, and self-assessing diagnostic platforms for the detection and monitoring of SARS-CoV-2 antibodies.

Our work developed a 3D SARS-CoV-2 antibody detection platform in non-invasive saliva samples using S1-RBD protein-immobilized 3D melt electrowritten poly(ε-caprolactone) scaffolds.

Iron accumulation is associated with periodontal destruction in a mouse model of HFE-related haemochromatosis

OBJECTIVE

To investigate the effect of Hfe gene mutation on the distribution of iron and periodontal bone loss in periodontal tissues.

BACKGROUND DATA

It remains unclear how tissue iron loading affects the periodontium architectures in a genetic animal model of hereditary haemochromatosis (HH).

METHODS

Male C57BL/6 Hfe^-/- (8 weeks old) and wild-type (WT) mice were utilized to examine the iron distribution in periodontal tissues, as well as periodontal tissues changes using micro-computed tomography and histomorphometric analysis. Furthermore, tissue inflammatory mediators, bone markers and periodontal pathogens were carried out in PFA-fixed paraffin-embedded tissues using ELISA, RT-qPCR and genomic DNA qPCR, respectively.

RESULTS

Excessive iron deposition was found in the periodontal ligament, gingiva and alveolar bone in Hfe^-/- mice relative to their WT counterparts. This, in turn, was associated with significant periodontal bone loss, increased cemento-enamel junction-alveolar bone crest distance and decreased expression of molecules involved in bone development and turnover. Furthermore, the pro-inflammatory cytokine - interleukin 6 and periodontal bacteria - Campylobacter rectus were significantly increased in Hfe^-/- mice compared with WT controls.

CONCLUSION

Our results suggest that the iron loading in a mouse model of HH decreases alveolar bone formation and leads to alterations in the inflammatory state in the periodontium. Periodontal health should be assessed during the clinical assessment of HFE-HH patients.

Investigation into the Phase-Activity Relationship of MnO2 Nanomaterials toward Ozone-Assisted Catalytic Oxidation of Toluene

Manganese dioxide (MnO₂ ), with naturally abundant crystal phases, is one of the most active candidates for toluene degradation. However, it remains ambiguous and controversial of the phase-activity relationship and the origin of the catalytic activity of these multiphase MnO₂ . In this study, six types of MnO₂ with crystal phases corresponding to α-, β-, γ-, ε-, λ-, and δ-MnO₂ are prepared, and their catalytic activity toward ozone-assisted catalytic oxidation of toluene at room temperature are studied, which follow the order of δ-MnO₂  > α-MnO₂  > ε-MnO₂  > γ-MnO₂  > λ-MnO₂  > β-MnO₂ . Further investigation of the specific oxygen species with the toluene oxidation activity indicates that high catalytic activity of MnO₂ is originated from the rich oxygen vacancy and the strong mobility of oxygen species. This work illustrates the important role of crystal phase in determining the oxygen vacancies' density and the mobility of oxygen species, thus influencing the catalytic activity of MnO₂ catalysts, which sheds light on strategies of rational design and synthesis of multiphase MnO₂ catalysts for volatile organic pollutants' (VOCs) degradation.

The emerging role of small extracellular vesicles in saliva and gingival crevicular fluid as diagnostics for periodontitis

Periodontitis is a highly prevalent multifactorial chronic inflammatory disease associated with a destructive host immune-inflammatory response to microbial dysbiosis. Current clinical diagnosis is reliant on measuring past periodontal tissue loss, with a lack of molecular biomarkers to accurately diagnose periodontitis activity in 'real-time'. Thus, discovery of new classes of diagnostic biomarkers is of critical importance in periodontology. Small extracellular vesicles (<200 nm in diameter; sEVs) from oral biofluids (saliva and gingival crevicular fluid-GCF) are lipid-encapsulated bilayered vesicles and have recently emerged as a potential source of biomarkers for periodontal disease (gingivitis and periodontitis), due to the cargo of protein, genetic material and lipids derived from their parent cells. There is limited information on the isolation and characterisation methods of saliva/GCF-sEVs or the characterisation of sEVs cargo as biomarkers for periodontitis. In this review, we detail the composition of sEVs and summarise their isolation and characterisation from saliva and GCF. The potential role of saliva and GCF-derived sEVs in periodontitis diagnosis is also explored. It is proposed that sEVs cargo, including protein, microRNA, message RNA and DNA methylation, are potential biomarkers for periodontitis with good diagnostic power (area under the curve-AUC > 0.9).