Antibody stabilization for thermally accelerated deep immunostaining.

Antibodies have diverse applications due to their high reaction specificities but are sensitive to denaturation when a higher working temperature is required. We have developed a simple, highly scalable and generalizable chemical approach for stabilizing off-the-shelf antibodies against thermal and chemical denaturation. We demonstrate that the stabilized antibodies (termed SPEARs) can withstand up to 4 weeks of continuous heating at 55 °C and harsh denaturants, and apply our method to 33 tested antibodies. SPEARs enable flexible applications of thermocycling and denaturants to dynamically modulate their binding kinetics, reaction equilibrium, macromolecular diffusivity and aggregation propensity. In particular, we show that SPEARs permit the use of a thermally facilitated three-dimensional immunolabeling strategy (termed ThICK staining), achieving whole mouse brain immunolabeling within 72 h, as well as nearly fourfold deeper penetration with threefold less antibodies in human brain tissue. With faster deep-tissue immunolabeling and broad compatibility with tissue processing and clearing methods without the need for any specialized equipment, we anticipate the wide applicability of ThICK staining with SPEARs for deep immunostaining.

Convergent dysbiosis of upper aerodigestive microbiota between patients with esophageal and oral cavity squamous cell carcinoma.

The bidirectional association between primary esophageal squamous cell carcinoma (ESCC) and oral cavity squamous cell carcinoma (OSCC) suggests common risk factors and oncogenic molecular processes but it is unclear whether these two cancers display similar patterns of dysbiosis in their upper aerodigestive microbiota (UADM). We conducted a case-control study to characterize the microbial communities in esophageal lavage samples from 49 ESCC patients and oral rinse samples from 91 OSCC patients using 16S rRNA V3-V4 amplicon sequencing. Compared with their respective non-SCC controls from the same anatomical sites, 32 and 45 discriminative bacterial genera were detected in ESCC and OSCC patients, respectively. Interestingly, 20 of them were commonly enriched or depleted in both types of cancer, suggesting a convergent niche adaptation of upper aerodigestive SCC-associated bacteria that may play important roles in the pathogenesis of malignancies. Notably, Fusobacterium, Selenomonas, Peptoanaerobacter and Peptostreptococcus were enriched in both ESCC and OSCC, whereas Streptococcus and Granulicatelia were commonly depleted. We further identified Fusobacterium nucleatum as the most abundant species enriched in the upper aerodigestive SCC microenvironment, and the higher relative abundances of Selenomonas danae and Treponema maroon were positively correlated with smoking. In addition, predicted functional analysis revealed several depleted (eg, lipoic acid and pyruvate metabolism) and enriched (eg, RNA polymerase and nucleotide excision repair) pathways common to both cancers. Our findings reveal a convergent dysbiosis in the UADM between patients with ESCC and OSCC, suggesting a shared niche adaptation of host-microbiota interactions in the pathogenesis of upper aerodigestive tract malignancies.

Fluid Biomarkers in HPV and Non-HPV Related Oropharyngeal Carcinomas: From Diagnosis and Monitoring to Prognostication-A Systematic Review.

Biomarkers are crucial in oncology, from detection and monitoring to guiding management and predicting treatment outcomes. Histological assessment of tissue biopsies is currently the gold standard for oropharyngeal cancers, but is technically demanding, invasive, and expensive. This systematic review aims to review current markers that are detectable in biofluids, which offer promising non-invasive alternatives in oropharyngeal carcinomas (OPCs). A total of 174 clinical trials from the PubMed search engine in the last 5 years were identified and screened by 4 independent reviewers. From these, 38 eligible clinical trials were found and subsequently reviewed. The biomarkers involved, categorized by human papillomavirus (HPV)-status, were further divided according to molecular and cellular levels. Recent trials investigating biomarkers for both HPV-positive and HPV-negative OPCs have approaches from various levels and different biofluids including plasma, oropharyngeal swabs, and oral rinse. Promising candidates have been found to aid in detection, staging, and predicting prognosis, in addition to well-established factors including HPV-status, drinking and smoking status. These studies also emphasize the possibility of enhancing prediction results and increasing statistical significance by multivariate analyses. Liquid biopsies offer promising assistance in enhancing personalized medicine for cancer treatment, from lowering barriers towards early screening, to facilitating de-escalation of treatment. However, further research is needed, and the combination of liquid biopsies with pre-existing methods, including in vivo imaging and invasive techniques such as neck dissections, could also be explored in future trials.

Recommendations for head and neck surgical oncology practice in a setting of acute severe resource constraint during the COVID-19 pandemic: an international consensus.

The speed and scale of the global COVID-19 pandemic has resulted in unprecedented pressures on health services worldwide, requiring new methods of service delivery during the health crisis. In the setting of severe resource constraint and high risk of infection to patients and clinicians, there is an urgent need to identify consensus statements on head and neck surgical oncology practice. We completed a modified Delphi consensus process of three rounds with 40 international experts in head and neck cancer surgical, radiation, and medical oncology, representing 35 international professional societies and national clinical trial groups. Endorsed by 39 societies and professional bodies, these consensus practice recommendations aim to decrease inconsistency of practice, reduce uncertainty in care, and provide reassurance for clinicians worldwide for head and neck surgical oncology in the context of the COVID-19 pandemic and in the setting of acute severe resource constraint and high risk of infection to patients and staff.

The role of tumor DNA as a diagnostic tool for head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) represents the most common type of head and neck cancer worldwide. However, despite advances in cancer care globally there has been little progress in HNSCC, with survival remaining static and slightly worse in laryngeal squamous cell carcinoma with 5 year survivals remaining at ∼50%. Conventional analysis of tissue through cytopathology or histopathology are the mainstay of diagnosis. Furthermore there are no useful biomarkers for disease diagnosis or surveillance. With recent technological advances, particularly in next generation sequencing, here we explore the application of tumor DNA for HNSCC diagnosis and surveillance, to improve surgical margin analysis and the potential use of molecular agents aiding in the imaging of HNSCC.

Early results of a safety and feasibility clinical trial of a novel single-port flexible robot for transoral robotic surgery.

The aim of this study was to describe the early results of a phase 1 safety and feasibility clinical trial of the first clinical use of a novel robot for transoral robotic surgery (TORS)-the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA). Study design of this study is prospective clinical trial. The methods used in this study are prospective innovation, development, exploration, assessment, and long-term study phase 1 clinical trial. Early results of six patients underwent TORS with the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA) demonstrate access the nasopharynx, oropharynx, larynx, and hypopharynx. There were no conversions of the robotic surgical system. There were no serious adverse events or adverse events related to the use of the robot at 30-day follow-up for all six patients. The early results of this safety and feasibility trial of the da Vinci SP (Intuitive Surgical Inc., Sunnyvale, CA, USA) clearly demonstrate that the device is safe and that it is feasible in performing TORS to access the nasopharynx, oropharynx, larynx, and hypopharynx.

Radiofrequency ablation compared to surgery for thyroid nodules: A case for office based treatment.

Objective: We aim to evaluate the safety and effectiveness of radiofrequency ablation (RFA) for benign thyroid nodules by ENT surgeons and to compare it to conventional hemithyroidectomy in the public healthcare, operating theater contained setting. Methods: 50 patients who underwent a single session of RFA for symptomatic benign thyroid nodules in Prince of Wales Hospital and Tseung Kwan O Hospital in Hong Kong from 2020 to 2022 were evaluated. Objective outcomes including nodule volume, volume reduction rate (VRR) and complications were recorded. Subjective response in the form of a 0-10 point scale for patient symptoms including obstructive, cosmetic, pain and satisfaction scores were collected. Results: Significant reduction in mean VRR was found at 3, 6 and 12 months post treatment, accompanied by a significant reduction in the mean obstructive and cosmetic symptom scores. Comparing with conventional hemithyroidectomy, the RFA group had a significantly shorter mean procedure time and lower rate of complications. Estimated cost to patient for RFA was found to be less than half of that of hemithyroidectomy. Conclusion: RFA is a safe and effective treatment modality for benign thyroid nodules by ENT surgeons with advantages of being a scarless local anesthetic procedure with shorter procedure time, lower complication rate and lower cost to patient compared to hemithyroidectomy. In Hong Kong, where most of the population is treated in the public sector, there are limited resources, often with high caseload burden and long operation waiting times. Therefore, RFA is an office-based treatment that serves as a valuable alternative to hemithyroidectomy for benign nodules, especially in lower resource settings. Level of evidence: 3.

A Safety and Feasibility Trial of Ultrasound-Guided Radiofrequency Ablation of Parotid Warthin's Tumor.

OBJECTIVE: To determine if ultrasound-guided (USG) radiofrequency ablation (RFA) of Parotid Warthin's tumor under local anesthesia is a safe and effective procedure. STUDY DESIGN: Safety and feasibility study. SETTING: Tertiary academic medical center. METHODS: This is an IDEAL phase 2a trial in a tertiary referral center. Twenty patients with Parotid Warthin's tumor were recruited. RFA was done between September and December 2021 for all 20 patients using a CoATherm AK-F200 machine with a disposable, 18G × 7 mm radiofrequency electrode. Results and follow-up statistics were compared with a historic sample of patients with parotid Warthin's tumor who underwent parotidectomy between 2019 and 2021 in the same center. RESULTS: Nineteen patients were included in the analysis as 1 patient dropped out after 4 weeks of follow-up. The mean age for the RFA group was 67 years old with most of them being male smokers. At a median of 45 weeks (44-47 weeks) postprocedure there was a 7.48 mL (68.4%) volume reduction compared to baseline. Three patients had transient facial nerve (FN) paresis, 1 recovered within hours, and the other 2 by 12 weeks follow-up. Three patients had great auricular nerve numbness; 1 patient had infected hematoma treated in an out-patient manner. Compared to a historic cohort of parotidectomy patients for Warthin's tumor, there was no significant difference in FN paresis and other minor complications between the 2 treatment modalities. CONCLUSION: The current analysis suggests that USG RFA of Warthin's Tumor is a safe alternative to parotidectomy with shorter operative time and length of stay.

Sodium-iodide symporter and its related solute carriers in thyroid cancer.

The solute carrier (SLC) family is a large group of membrane transport proteins. Their dysfunction plays an important role in the pathogenesis of thyroid cancer. The most well-known SLC is the sodium-iodide symporter (NIS), also known as sodium/iodide co-transporter or solute carrier family 5 member 5 (SLC5A5) in thyroid cancer. The dysregulation of NIS in thyroid cancer is well documented. The role of NIS in the uptake of iodide is critical in the treatment of thyroid cancer, radioactive iodide (RAI) therapy in particular. In addition to NIS, other SLC members may affect the autophagy, proliferation, and apoptosis of thyroid cancer cells, indicating that an alteration in SLC members may affect different cellular events in the evolution of thyroid cancer. The expression of the SLC members may impact the uptake of chemicals by the thyroid, suggesting that targeting SLC members may be a promising therapeutic strategy in thyroid cancer.

Comparison of da Vinci Single Port vs Si Systems for Transoral Robotic-Assisted Surgery: A Review With Technical Insights.

Importance: Transoral robot-assisted surgery (TORS) continues to have a major role in the treatment of oropharyngeal cancer. As new iterations of robotic technology are increasingly utilized, it is important to share learning experiences and clinical outcomes data, to optimize technical efficiency and clinical care. Observations: This was a retrospective review of a large academic institution's initial clinical use of the da Vinci Single Port (SP) compared with the da Vinci Si (Si) system. A total of 205 TORS cases were reviewed: 109 in the SP group (November 22, 2018, through September 30, 2020), and 96 in the Si group (January 1, 2016, through November 12, 2018). Both groups had comparable operative times, rates of postoperative pharyngeal hemorrhage, length of hospital stay, and duration of nasogastric feeding tube use. There was no difference in pathological characteristics, rates of positive margins, or indications for or time to initiation of adjuvant therapy between the groups. The collective experience of 6 faculty members-who have trained 139 TORS surgeons for the SP system rollout-was compiled to provide a summary of learning experiences and technical notes on safe and efficient operation of the SP system. Conclusions and Relevance: This Review found that the functional and oncologic outcomes were comparable between TORS cases performed with the Si and SP systems, and they had similar complication rates. Recognized advantages of the SP over the Si system include the availability of bipolar-energized instruments, a usable third surgical arm, and improved camera image quality.

Changes in the Incidence and Human Papillomavirus-Positive Portion of Oropharyngeal Squamous Cell Carcinoma in Hong Kong.

The incidence of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) is rising in the West, but little is known in Asia. This study elucidated changes in the incidence and HPV-positive portion of OPSCC in Hong Kong. Data from population-based cancer registry were used to analyze the incidence of OPSCC in association with other head and neck cancers. Archived tumor tissues were tested for HPV. From 1986 to 2020, there was a marked decrease in the incidence of nasopharyngeal and laryngeal cancers, but a persistent increase in OPSCC from 36 cases in 1986 to 116 cases in 2020. The average positive rate for high-risk HPV was 36.1% (112/310) among OPSCC diagnosed in 2010-2020. The HPV-positive rate in recent years was significantly higher than earlier cases (tonsil SCC: 64.7% (55/85) in 2016-2020 vs. 40.4% (19/47) in 2010-2015, p = 0.007). Patients with HPV-positive tonsil cancers were significantly younger than those negative (mean [SD]: 58.9 [9.9] vs. 64.3 [13.3] years, p = 0.006), but no significant difference was observed between genders. A persistent increase in the incidence of oropharyngeal cancer over the last few decades was observed in Hong Kong, which can be explained by the remarkable increase in HPV-positive tonsil cancers.

Integrative analysis reveals associations between oral microbiota dysbiosis and host genetic and epigenetic aberrations in oral cavity squamous cell carcinoma.

Dysbiosis of the human oral microbiota has been reported to be associated with oral cavity squamous cell carcinoma (OSCC) while the host-microbiota interactions with respect to the potential impact of pathogenic bacteria on host genomic and epigenomic abnormalities remain poorly studied. In this study, the mucosal bacterial community, host genome-wide transcriptome and DNA CpG methylation were simultaneously profiled in tumors and their adjacent normal tissues of OSCC patients. Significant enrichment in the relative abundance of seven bacteria species (Fusobacterium nucleatum, Treponema medium, Peptostreptococcus stomatis, Gemella morbillorum, Catonella morbi, Peptoanaerobacter yurli and Peptococcus simiae) were observed in OSCC tumor microenvironment. These tumor-enriched bacteria formed 254 positive correlations with 206 up-regulated host genes, mainly involving signaling pathways related to cell adhesion, migration and proliferation. Integrative analysis of bacteria-transcriptome and bacteria-methylation correlations identified at least 20 dysregulated host genes with inverted CpG methylation in their promoter regions associated with enrichment of bacterial pathogens, implying a potential of pathogenic bacteria to regulate gene expression, in part, through epigenetic alterations. An in vitro model further confirmed that Fusobacterium nucleatum might contribute to cellular invasion via crosstalk with E-cadherin/ß-catenin signaling, TNFα/NF-κB pathway and extracellular matrix remodeling by up-regulating SNAI2 gene, a key transcription factor of epithelial-mesenchymal transition (EMT). Our work using multi-omics approaches explored complex host-microbiota interactions and provided important insights into genetic and functional basis in OSCC tumorigenesis, which may serve as a precursor for hypothesis-driven study to better understand the causational relationship of pathogenic bacteria in this deadly cancer.

A case of congenital agenesis of the common carotid artery associated with an ectopic parathyroid adenoma mimicking a carotid body tumor.

Ectopic parathyroid adenomas can be encountered during four gland explorations, but nearly 80% of adenomas are localized with ultrasound and sestamibi imaging. Ectopic adenomas are thought to arise from abnormal migration during development. As a cervical congenital anomaly, common carotid artery agenesis is an extremely rare anomaly characterized by separate origins of the internal and external carotid arteries directly from the aortic arch. Here we present a case of a 75 year old man with primary hyperparathyroidism who was found to have congenital agenesis of the common carotid artery associated with an ectopic parathyroid adenoma within the parapharyngeal space, which mimicked a carotid body tumor based on location and imaging. The successful identification and resection of the ectopic parathyroid adenoma presented here demonstrate the importance of preoperative imaging studies to allow appropriate operative planning as well as the utility of intraoperative parathyroid hormone assay in predicting cure during surgery.

Systematic review on oral microbial dysbiosis and its clinical associations with head and neck squamous cell carcinoma.

OBJECTIVES: The relationship between head and neck squamous cell carcinoma (HNSCC) and the oral microbiome has been drawn in various studies. Microbial diversities, microbiome profiles, metagenomic analysis, and host-pathogen interactions were collected from these studies to highlight similarities and account for inconsistencies. We also evaluate the possible clinical applications of the microbiome regarding screening and diagnosis of HNSCC. METHODS: Systematic analysis of studies regarding HNSCC and the microbiome was done according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines. Articles were retrieved from four databases (PubMed, ScienceDirect, CUHK Full-Text Journals, and Cochrane database) and were screened using predefined criteria. RESULTS: Twenty studies were chosen after screening for full-text review. α-diversity comparison was inconsistent whereas ß-diversity between HNSCC and normal samples showed distinct clustering. Microbial dysbiosis characterized by change in the relative abundances of several bacterial species were also seen in HNSCC patients. At a phylum level, inconsistencies were seen between studies using HNSCC tumor tissue samples and saliva samples. At a genus level, Fusobacterium, Peptostreptococcus, Alloprevotella, Capnocytophaga, Catonella, and Prevotella were differentially enriched in HNSCC while Streptococcus, Actinomyces Veillonella, and Rothia were differentially depleted. Co-occurrence network analysis revealed a positive correlation of HNSCC with periodontal pathogens and a negative correlation with commensal bacteria. Metagenomic analysis of microbiota revealed a differential enrichment of pro-inflammatory genomic pathways which was consistent across various studies. Microbial dysbiosis was applied in clinical use as a tool for HNSCC screening. Random-forest analysis was adopted to differentiate between tumor and normal tissue, at 95.7% and 70.0% accuracies respectively in two studies. Microbial dysbiosis index was also used to predict prognosis. CONCLUSIONS: Oral microbial dysbiosis could be a promising tool for HNSCC screening and diagnosis. However, more research should be conducted pertaining to clinical applications to improve diagnostic accuracy and explore other clinical uses.

Extent of Oral-Gut Transmission of Bacterial and Fungal Microbiota in Healthy Chinese Adults.

Recent studies have provided evidence on the presence of an oral-gut microbiota axis in gastrointestinal diseases; however, whether a similar axis exists in healthy individuals is still in debate. Here, we characterized the bacterial and fungal microbiomes in paired oral rinse and stool samples collected from 470 healthy Chinese adults by sequencing the 16S rRNA V3-V4 and ITS1 regions, respectively. We hypothesized that there is limited oral-gut transmission of both the bacterial and fungal microbiota in healthy Chinese adults. Our results showed that the oral and gut microbiota in healthy individuals differed in taxonomic composition, alpha and beta diversity, metabolic potential, and network properties. Bayesian analysis showed that the vast majority of subjects had negligible or low bacterial and fungal oral-to-stool contribution. Detailed examination of the prevalent amplicon sequence variants (ASVs) also revealed limited cases of sharing between the oral and stool samples within the same individuals, except a few bacterial and fungal ASVs. Association analysis showed that sharing of the potentially transmissible fungal ASVs was associated with host factors, including an older age and a higher body mass index. Our findings indicate that oral-gut transmission of both bacterial and fungal microbiota in healthy adults is limited. Detection of a large amount of shared bacterial or fungal members between the oral and gut microbiome of an individual may indicate medical conditions that warrant detailed checkup. IMPORTANCE The oral-gut microbiota axis in health is a fundamentally important and clinically relevant topic; however, our current understanding of it remains biased and incomplete. By characterizing the bacterial and fungal microbiomes in paired oral rinse and stool samples from a large cohort of healthy Chinese adults, here we provided new evidence that oral-gut microbiota transmission is limited in non-Western population and across biological domains. Our study has established an important baseline of a healthy oral-gut microbiota axis, with which other disease conditions can be compared. Besides, our findings have practical implications that detection of a large amount of shared bacterial or fungal members between the oral cavity and gut within the same individual as an indicator of potential medical conditions.

Combining Transoral Nasopharyngeal Brush and Plasma Epstein-Barr Virus DNA in Detecting Locally Recurrent Nasopharyngeal Carcinoma.

OBJECTIVE: To evaluate the sensitivities and specificities of Epstein-Barr virus (EBV) DNA in the detection of locally recurrent or persistent nasopharyngeal carcinoma (NPC) through nasopharyngeal (NP) brush biopsy and plasma, respectively, and whether a combination of both would be superior to the individual tests. STUDY DESIGN: A case-control study was conducted from September 2016 to June 2022. SETTING: A multicentre study at 3 tertiary referral centers in Hong Kong was conducted by the Department of Otorhinolaryngology, Head and Neck Surgery, The Chinese University of Hong Kong. METHODS: Twenty-seven patients with biopsy-confirmed locally recurrent NPC were recruited as study subjects. Magnetic resonance imaging was performed to rule out regional recurrence. The control group consisted of 58 patients with a prior history of NPC who were now disease-free based on endoscopic and imaging findings. Patients underwent both the transoral NP brush (NP Screen®) and blood for plasma Epstein-Barr DNA levels. RESULTS: The sensitivity and specificity of the combined modalities were 84.62% and 85.19%, respectively. The positive predictive value was 73.33% and the negative predictive value was 92.0%. CONCLUSION: The combination of NP brush biopsy and plasma EBV DNA is potentially an additional surveillance modality in detecting the local recurrence of NPC. Further study with a larger sample size would be required to validate the cutoff values.

SMARCB1 (INI1)-Deficient Sinonasal Carcinoma with Yolk Sac differentiation Showing Co-loss of SMARCA4 Immunostaining - A Case Report and Literature Review.

SMARCB1 (INI1)-deficient carcinoma of the sinonasal tract is a rare and distinct entity characterized by the loss of INI1 immunostain expression. These tumors are morphologically diverse, with isolated cases of yolk sac differentiation reported. We report the first case of SMARCB1-deficient sinonasal carcinoma that demonstrated co-loss of SMARCA4 immunostain, and reduced SMARCA2 and ARID1A staining, with the entire tumor showing histological and immunohistochemical evidence of yolk sac differentiation. The clinical, histological, immunohistochemical and molecular features were discussed and compared against SMARCB1-deficient sinonasal carcinomas with yolk sac differentiation and SMARCA4-deficeint sinonasal carcinomas reported in the literature. With a highly aggressive clinical course leading to mortality two months after presentation, the behavior of this tumor appears to be more comparable to that of SMARCA4-deficient sinonasal carcinomas. A comprehensive immunopanel including SMARCB1, SMARCA4, SMARCA2 and ARID1A may be advisable for assessment and prognostication of SWI/SNF-deficient tumors.

The Isoforms of Estrogen Receptor Alpha and Beta in Thyroid Cancer.

The incidence of thyroid cancer was predominant in women, indicating that the sex hormone may have a role in thyroid cancer development. Generally, the sex hormone exerts its function by binding to the correspondent nuclear receptors. Therefore, aberrant of these receptors may be involved in the development of thyroid cancer. Estrogen receptor alpha (ERα) and beta (ERß), two main estrogen receptors, have been reported to have an important role in the pathogenesis of thyroid cancer. When the ERα and ERß genes undergo the alternative RNA splicing, some ERα and ERß isoforms with incomplete functional domains may be formed. To date, several isoforms of ERα and ERß have been identified. However, their expression and roles in thyroid cancer are far from clear. In this review, we summarized the expressions and roles of ERα and ERß isoforms in thyroid cancer, aiming to provide the perspective of modulating the alternative RNA splicing of ERα and ERß against thyroid cancer.

Determinants and Interactions of Oral Bacterial and Fungal Microbiota in Healthy Chinese Adults.

Numerous studies have examined the composition of and factors shaping the oral bacterial microbiota in healthy adults; however, similar studies on the less dominant yet ecologically and clinically important fungal microbiota are scarce. In this study, we characterized simultaneously the oral bacterial and fungal microbiomes in a large cohort of systemically healthy Chinese adults by sequencing the bacterial 16S rRNA gene and fungal internal transcribed spacer. We showed that different factors shaped the oral bacterial and fungal microbiomes in healthy adults. Sex and age were associated with the alpha diversity of the healthy oral bacterial microbiome but not that of the fungal microbiome. Age was also a major factor affecting the beta diversity of the oral bacterial microbiome; however, it only exerted a small effect on the oral fungal microbiome when compared with other variables. After controlling for age and sex, the bacterial microbiota structure was most affected by marital status, recent oral conditions and oral hygiene-related factors, whereas the fungal microbiota structure was most affected by education level, fruits and vegetables, and bleeding gums. Bacterial-fungal interactions were limited in the healthy oral microbiota, with the strongest association existing between Pseudomonas sp. and Rhodotorula dairenensis. Several bacterial amplicon sequence variants (ASVs) belonging to Veillonella atypica and the genera Leptotrichia, Streptococcus and Prevotella_7 and fungal ASVs belonging to Candida albicans and the genus Blumeria were revealed as putative pivotal members of the healthy oral microbiota. Overall, our study has facilitated understanding of the determining factors and cross-kingdom interactions of the healthy human oral microbiome. IMPORTANCE Numerous studies have examined the bacterial community residing in our oral cavity; however, information on the less dominant yet ecologically and clinically important fungal members is limited. In this study, we characterized simultaneously the oral bacterial and fungal microbial communities in a large cohort of healthy Chinese adults, examined their associations with an array of host factors, and explored potential interactions between the two microbial groups. We showed that different factors shape the diversity and structure of the oral bacterial and fungal microbial communities in healthy adults, with, for instance, sex and age only associated with the diversity of the bacterial community but not that of the fungal community. Besides, we found that bacterial-fungal interactions are limited in the healthy oral cavity. Overall, our study has facilitated understanding of the determining factors and bacterial-fungal interactions of the healthy human oral microbial community.

Endoscope-assisted magnetic helical micromachine delivery for biofilm eradication in tympanostomy tube.

Occlusion of the T-tube (tympanostomy tube) is a common postoperative sequela related to bacterial biofilms. Confronting biofilm-related infections of T-tubes, maneuverable and effective treatments are still challenging presently. Here, we propose an endoscopy-assisted treatment procedure based on the wobbling Fe2O3 helical micromachine (HMM) with peroxidase-mimicking activity. Different from the ideal corkscrew motion, the Fe2O3 HMM applies a wobbling motion in the tube, inducing stronger mechanical force and fluid convections, which not only damages the biofilm occlusion into debris quickly but also enhances the catalytic generation and diffusion of reactive oxygen species (ROS) for killing bacteria cells. Moreover, the treatment procedure, which integrated the delivery, actuation, and retrieval of Fe2O3 HMM, was validated in the T-tube implanted in a human cadaver ex vivo. It enables the visual operation with ease and is gentle to the tympanic membrane and ossicles, which is promising in the clinical application.