Gustatory dysfunction and long COVID in Chinese patients with COVID-19: A 6-month follow-up study.

AIMS: To evaluate long COVID of gustatory dysfunction and the associated risk factors regarding onset and recovery in Chinese patients. METHODS: We conducted a cross-sectional study of patients with SARS-CoV-2 Omicron infection at Changxing Mobile Cabin Hospital in Shanghai, China, from March to May 2022. A prospective follow-up of patients with gustatory dysfunction was conducted at 6 months after discharge. RESULTS: In total, 18.48% (241/1304) reported gustatory dysfunction. The 6-month follow-up response rate was 89.63% (216/241) and 74.02% recovered their taste sense within 1-3 weeks. A total of 20.37% of patients (44/216) presented with long COVID. Symptoms persisted for 12 patients (5.56%) after 6 months. Having multiple taste impairments (OR, 2.364; 95% CI, 1.286-4.348; p = 0.006) was associated with a higher risk of gustatory dysfunction with long COVID. Having received a COVID-19 vaccine booster was positively associated with taste sensation recovery (HR, 1.344; 95% CI, 1.012-1.785; p = 0.041). CONCLUSIONS: About 20.37% of patients with COVID-19 might develop long COVID of gustatory dysfunction and 5.56% with persisting changes in their sense of taste. Most patients recovered taste sensations within 1-3 weeks after COVID-19 symptom onset and receiving a booster shot of the COVID-19 vaccine presented a protective effect on the taste sensation recovery.

Dynamic salivary cytokine profile of recurrent aphthous stomatitis patients in thalidomide maintenance treatment.

OBJECTIVE: To dynamically compare the longitudinal (time axis) and transverse (between groups) differences of the salivary cytokines during thalidomide maintenance treatment of recurrent aphthous stomatitis. METHODS: A randomized, controlled, clinical trial was performed. After the initial prednisone treatment, thalidomide (50 mg/d vs. 25 mg/d) was used as a maintenance drug for 4 or 8 weeks. The salivary IL-4, 5, 6, 10, TNF-α, and IFN-γ were dynamically detected with a cytometric bead array. RESULTS: Overall, the level of six elevated salivary cytokines after prednisone treatment was significantly downregulated, remained low during thalidomide maintenance, and rebounded at recurrence. The effect of 50 mg/d thalidomide on the salivary cytokines was not superior to 25 mg/d medication. The relapse-free period following drug withdrawal was the longest in the subgroup using 25 mg/d thalidomide for 8 weeks. The order of magnitude of IL-6 was the most obvious, and at week 8, only the level of IL-6 in the group (25 mg/d thalidomide for 8 weeks) continued to decline compared with the other groups. CONCLUSION: Thalidomide maintenance treatment can effectively sustain low levels of salivary IL-4, 5, 6, 10, TNF-α, and IFN-γ of recurrent aphthous stomatitis patients. IL-6 displayed a good correlation with the disease and is expected to become an index for diagnosis and follow-up. CLINICAL RELEVANCE: Low-dose long-term thalidomide maintenance treatment was supported for recurrent aphthous stomatitis. TRIAL REGISTRATION: Trial registration number of ChiCTR-IPR-16009759 at http://www.chictr.org/index.aspx .

Elevated serum fibrinogen levels in Chinese patients with minor recurrent aphthous stomatitis: An observational study.

Fibrinogen is a protein that reflects systemic inflammation and regulates the immune response to disease. However, there is a scarcity of data on fibrinogen in recurrent aphthous stomatitis (RAS). We aimed to test the hypothesis that fibrinogen is involved in the aetiology of RAS. Between November 2016 and November 2018, we included 109 minor RAS patients and 29 age- and sex-matched controls in a single-center, observational study. Their clinical history and ulcer manifestations led to the diagnosis of minor RAS. The ulcer severity score (USS) was used to assess disease severity, and fibrinogen was also collected. We conducted three analyses: Analysis 1 (comparison of fibrinogen levels between patients and controls), Analysis 2 (comparison of fibrinogen levels between high and low USS patients) and Analysis 3 (comparison of fibrinogen levels between before and after anti-inflammatory treatment in patients). The fibrinogen levels in the 109 minor RAS patients were statistically higher than in the 29 controls (mean [SD], 2.6 [0.5] vs. 2.3 [0.3]; Student's t-test, p < 0.001). However, there were no significant differences in fibrinogen levels among the 43 patients with high USS and the 39 patients with low USS (mean [SD], 2.7 [0.5] vs. 2.6 [0.4]; Student's t-test, p = 0.278). Furthermore, fibrinogen levels were significantly higher before anti-inflammatory treatment in comparison to those after anti-inflammatory treatment in the 35 paired patients (mean [SD], 2.6 [0.4] vs. 2.5 [0.4]; Student's t-test, p = 0.026). Interestingly, fibrinogen levels were significantly higher in the 35 paired patients after anti-inflammatory treatment compared to the 29 control subjects (mean [SD], 2.5 [0.4] vs. 2.3 [0.3]; Student's t-test, p = 0.026]. Fibrinogen may play a role in the aetiology of RAS and may be a drug target for RAS treatment. Clinicians should be alert that high serum fibrinogen levels might be associated with the risk of RAS.

Cardiovascular diseases, risk factors, and ulcer relapse in older adults with aphthous stomatitis.

OBJECTIVES: To test the hypothesis that cardiovascular diseases and risk factors are associated with ulcer relapse in after-retirement patients with recurrent aphthous stomatitis. SUBJECTS AND METHODS: This retrospective cohort study analyzed the data of 40 minor recurrent aphthous stomatitis patients aged 55-75 years, admitted to Oral Medicine Clinic at one university hospital in China between 2016 and 2018. The diagnosis of minor recurrent aphthous stomatitis was made based on the history and manifestation of oral ulcers. The ulcer relapse was evaluated after a 5-week anti-inflammatory treatment, and the history of systemic diseases was collected. cardiovascular disease/metabolic risk referred to the presence of any cardiovascular diseases and metabolic cardiovascular disease risks. Associations among cardiovascular diseases, risk factors, and ulcer relapse were evaluated. RESULTS: The mean age of 40 patients with minor recurrent aphthous stomatitis was 62.4 years (SD 5.1), and 60% were women. The ulcer relapse rate was 37.5% (95% CI, 0.242-0.530). The proportion of cardiovascular disease/metabolic risk was higher in the relapse group than in the no-relapse group after 5-week anti-inflammatory treatment (Fisher's exact test, p = 0.041). CONCLUSIONS: According to this single-center experience, older patients with cardiovascular disease/metabolic risk may be more prone to oral ulcer recurrence. Nevertheless, larger prospective studies are needed to confirm our findings.

A multi-center cross-sectional study of 1495 Chinese oral lichen planus patients.

OBJECTIVE: To explore the clinical epidemiological characteristics of oral lichen planus (OLP) and risk factors for erosive/ulcerative OLP. MATERIALS AND METHODS: Patients diagnosed with OLP from 11 different hospitals were included in the study. Descriptive statistical methods were used to explore the clinical epidemiological characteristics and logistic regression, sensitivity analysis, and subgroup analysis were utilized to explore the risk factors for erosive/ulcerative OLP. RESULTS: The average age of patients was 49.2 ± 13.3 years, and 61.4% of the patients were women. The ratios of patients with reticular, hyperemic/erythematous, and erosive/ulcerative lesions were 47.9%, 27.8%, and 24.2%, respectively. Analysis of risk factors for erosive/ulcerative OLP identified the following variables: age, course of disease of 12 months or more, II°-III° dental calculus, hypertension, diabetes, and heart disease, as well as regions of habitation. Subgroup analysis showed significant differences in risk factors for erosive/ulcerative OLP in patients with and without risk behaviors. CONCLUSION: The clinical epidemiological characteristics of patients with OLP in the Chinese population in this study are basically consistent with existing reports in developed countries. And we identified clinical characteristics associated with erosive/ulcerative OLP through clinical epidemiological analysis.

Hydroxychloroquine is effective in oral lichen planus: A multicenter, randomized, controlled trial.

OBJECTIVES: This study was aimed to evaluate the safety and benefit of short-term application of hydroxychloroquine in the management of atrophic/erosive/ulcerative oral lichen planus (OLP). METHODS: This multicenter, randomized, controlled, evaluator-blinded, prospective clinical trial was performed from October 1, 2019, to September 1, 2022. A total of 99 patients were randomized to receive systemic use of hydroxychloroquine (n = 50), or topical use of 0.05% dexamethasone (n = 49) for 4 weeks. The response to both treatment modalities was evaluated according to reticulation, hyperemic, and ulceration (RHU) score and visual analog scale (VAS) score. RESULTS: After 4 weeks of medication, both groups showed substantial reduction in RHU and VAS score (p < 0.05). In hydroxychloroquine group, the average of RHU score was reduced from 10.60 to 7.68 (dropped 27.49%), and the average of VAS score was reduced from 3.74 to 2.47 (dropped 34.09%). There were no differences between the two groups in reduction of RHU score and VAS score (p > 0.05). Single factor analysis found hyperemic area (p = 0.019) and erosive/ulcerative area (p = 0.024) had impacts on drug efficacy of hydroxychloroquine, and logistic regression revealed that no factors (p > 0.05) influenced its efficacy. CONCLUSION: These findings indicate hydroxychloroquine is a safe and effective agent in treating atrophic/erosive/ulcerative OLP.

Effects of low-level laser therapy on burning pain and quality of life in patients with burning mouth syndrome: a systematic review and meta-analysis.

BACKGROUND: Burning mouth syndrome (BMS) is a complex chronic pain disorder that significantly impairs patients' quality of life. Low-level laser therapy (LLLT) uses infrared or near-infrared light to produce analgesic, anti-inflammatory, and biological stimulation effects. The aim of this systematic review is to evaluate the effect of LLLT on burning pain, quality of life, and negative emotions in patients with BMS. METHODS: The PubMed, Embase, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Cochrane Library, Web of Science, and Scopus databases were searched up January 2023 to identify relevant articles. All randomized controlled trials that were published in English and examined the use of LLLT treatment for BMS were included. The methodological quality of the included trials was assessed using the Cochrane risk of bias tool for randomized controlled trials (RCTs). A meta-analysis was performed to evaluate burning pain, quality of life, and negative emotions. Sensitivity, subgroup, and funnel plot analyses were also carried out. RESULTS: Fourteen RCTs involving a total of 550 patients with BMS met the inclusion criteria. The results showed that LLLT (measured by the Visual Analog Scale; SMD: -0.87, 95% CI: -1.29 to -0.45, P < 0.001) was more effective for reducing burning pain than placebo LLLT or clonazepam. LLLT improved quality of life (evaluated by the Oral Health Impact Profile-14; SMD: 0.01, 95% CI: -0.58 to 0.60, P = 0.97) and negative emotions (evaluated by the Hospital Anxiety and Depression Scale; SMD: -0.12, 95% CI: -0.54 to 0.30, P = 0.59), but these effects were not statistically significant. CONCLUSIONS: The meta-analysis revealed that LLLT may be an effective therapy for improving burning pain in patients with BMS, and producing a positive influence on quality of life and negative emotions. A long-term course of intervention, a larger sample size, and a multidisciplinary intervention design are urgently needed in future research. TRIAL REGISTRATION: PROSPERO registration number: CRD42022308770.

Palatal perforation caused by Alternaria alternata infection in an immunocompetent adolescent.

Opportunistic oral mucosal fungal infection caused by Alternaria alternata is extremely rare. Herein, we present a rare palatal perforation as a result of oral infection caused by A. alternata in an immunocompetent adolescent. An 18-year-old boy, who had previously been healthy, was admitted to our institution with persistent pain in the palate for the past 12 months. Upon impression of palatal bone resorption based on computed tomography imaging and chronic granulomatous inflammation based on biopsy (hematoxylin-eosin staining), the patient was examined for commonly relevant causes such as potential tumor and Mycobacterium tuberculosis infection. All test results were inconclusive. After a thorough diagnostic investigation, an unusual fungal infection, A. alternata infection, was confirmed by next-generation sequencing and biopsy (periodic acid-Schiff staining and immunofluorescence staining). The patient underwent surgical debridement and was subjected to voriconazole treatment postoperatively for over a period of 5 months. Thus, these findings highlight the importance of considering A. alternata as a potential pathogenic factor in an etiological palatal perforation.

[Effects of Fusobacterium nucleus derived outer membrane vesicles on claudin-4 expression in oral epithelial cells].

PURPOSE: To investigate the effect of outer membrane vesicles (OMVs) secreted by Fusobacterium nucleatum (F.n) on Claudin-4 of human oral keratinocytes (HOK) and oral epithelial barrier function. METHODS: Fusobacterium nucleatum was cultured under anaerobic conditions. The OMVs were extracted by dialysis and characterized by nanosight and transmission electron microscopy (TEM). HOK were stimulated with OMVs at different mass concentrations(0-100 µg/mL) for 12 h, and stimulated with 100 µg/mL OMVs for 6 h and 12 h respectively. The expression of Claudin-4 at gene and protein level was analyzed by RT-qPCR and Western blotting. Inverted fluorescence microscope was used to observe co-localization of HOK and OMVs and localization and distribution of Claudin-4 protein. Human oral epithelial barrier was constructed by Transwell apical chamber. Transepithelial electrical resistance(TER) of barrier was measured with a transmembrane resistance measuring instrument(EVOM2), and the permeability of the barrier was evaluated by transmittance of fluorescein isothiocyanate-dextran(FD-4). Statistical analysis was performed with GraphPad Prism 8.0 software package. RESULTS: Compared with the control group, the expression of Claudin-4 at protein and gene level in the HOK of OMVs stimulated group was significantly reduced (P＜0.05), and immunofluorescence showed that the continuity of Claudin-4 fluorescence among cells was destroyed. OMVs stimulation decreased TER value of oral epithelial barrier(P＜0.05) and increased the transmittance of FD-4(P＜0.05). CONCLUSIONS: OMVs derived from Fusobacterium nucleatum may damage oral mucosal epithelial barrier function through inhibiting the expression of Claudin-4.

Preliminary analysis of the buccal mucosal fungal microbiome in oral lichen planus patients.

OBJECTIVE: To determine the structure and co-occurrence patterns of mucosal fungal community in oral lichen planus (OLP) patients. SUBJECTS AND METHODS: Mucosal swab samples from 20 OLP patients and 10 healthy controls (HCs) were collected and the mucosal mycobiomes were sequenced. The abundance, frequency, and diversity of fungi were analyzed, as well as the inter-genera interactions. The associations between fungal genera and OLP severity were further identified. RESULTS: At the genus level, the relative abundance of unclassified_Trichocomaceae was significantly decreased in the reticular and erosive OLP groups compared to HCs. Meanwhile, significantly lower levels of Pseudozyma were observed in the reticular OLP group compared to HCs. The negative:positive cohesiveness ratio was significantly lower in the OLP group than HCs, indicating a relatively unstable fungal ecological system in the OLP group. In the OLP group, the abundance of unclassified_Nectriaceae was significantly correlated with the reticulation/erythema/ulceration (REU) score. CONCLUSIONS: Compared to HCs, the decreased stability of fungal communities and the decreased abundances of two genera (unclassified_Trichocomaceae and Pseudozyma) on buccal mucosa were identified in OLP patients.

TRIM21 promotes inflammation by ubiquitylating NF-κB in T cells of oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is a mucocutaneous inflammatory disease affecting 1% general population. Tripartite motif-containing protein 21 (TRIM21) shows a significant role in OLP. This study aimed to explore the function and mechanism of TRIM21 in T cells of OLP. METHODS: Differential gene expression profile in OLP versus healthy controls (HCs) was constructed by RNA sequencing. Protein expression level and infiltration sites of TRIM21 in OLP were detected by immunoblot, immunohistochemistry, and immunofluorescence. Expression of proinflammatory cytokines and chemokines including IL-6, TNF-α, ICAM1, CXCL1, CXCL8, CXCL9, and CXCL11 in CD3+ TRIM21hi T cells were measured by quantitative real-time polymerase chain reaction analysis. Downstream pathways and substrates of TRIM21 were explored by immunoblot and immunoprecipitation. Whether TRIM21 ubiquitination its substrate and ubiquitination form were tested by ubiquitination assay in vitro. RESULTS: Compared with HCs, TRIM21 exhibited a higher level in OLP, which expressed mainly in CD3+ T lymphocytes in OLP tissues. Overexpressed TRIM21 enhanced the expression of IL-6, TNF-α, CXCL1, CXCL8, CXCL9, and CXCL11 in CD3+ T cell line through ubiquitinating nuclear factor-κB (NF-κB) via a lysine 63 (K63) linkage, which eventually activating NF-κB signaling pathway. CONCLUSIONS: In OLP, TRIM21 promoted inflammation through ubiquitylating NF-κB and activating NF-κB signaling pathway.

Preliminary analysis of mucosal and salivary bacterial communities in oral lichen planus.

OBJECTIVE: To characterize the bacterial community from different oral niches (buccal mucosa and saliva) in oral lichen planus (OLP) patients. SUBJECTS AND METHODS: This preliminary study analyzed site-specific (mucosa and saliva) microbial landscape of 20 OLP patients and 10 healthy controls. RESULTS: The microbial diversity was similar between OLP patients and healthy controls in both salivary and mucosal communities. However, the topological properties of co-occurrence networks of salivary and mucosal microbiome were different between healthy controls and OLP patients. SparCC analysis inferred three and five keystone taxa in the salivary and mucosal microbial networks of healthy controls, respectively. However, in the salivary and mucosal bacterial networks of OLP patients, only one hub OTU and three OTUs were identified as keystone taxa, respectively. In addition, analysis of community cohesion revealed that mucosal microbial community in OLP patients had lower stability than that in healthy controls. In final, correlation assay showed that the clinical severity of OLP was positively associated with the relative abundance of Rothia in saliva but negatively associated with that of Porphyromonas on mucosa. CONCLUSIONS: The salivary and mucosal bacterial communities of OLP patients differ in terms of composition, the genera associated with OLP severity, and co-occurrence patterns.

An improved scoring system for monitoring oral lichen planus: A preliminary clinical study.

OBJECTIVES: To design an improved oral lichen planus (OLP) scoring system, which can be widely applied. SUBJECTS AND METHODS: A new scoring system that took reticulation, hyperemia and ulceration (RHU) into account, named as RHU scoring system, was designed for OLP patients' management. The patients were also scored for the reticulation/erythema/ulcer (REU) scoring system, physician global assessment (PGA), numerical rating scale (NRS) and Oral Health Impact Profile-14 (OHIP-14). The reliability and validity analyses were utilized to assess the RHU scoring system. We further applied the RHU scoring system to examine the treatment outcomes of topical dexamethasone sodium phosphate and general hydroxychloroquine hydrochloride among OLP patients. RESULTS: Forty-eight OLP patients from two medical centers were recruited. This new scoring system has reliability with an internal consistency index Cronbach α 0.49. The Pearson correlation of RHU score with PGA and REU score were 0.891 and 0.675 (p < 0.05) respectively, reflecting satisfactory standard validity. A 10% change in RHU score was used as the disease condition evaluation standard, reflecting satisfactory discriminating validity (t = -5.821, p < 0.001). During follow-ups, scores of all scales decreased at each re-visit. The drop between each visit of OHIP-14 fluctuated compared with the RHU system and NRS. CONCLUSIONS: As a semi-quantitative score system, the RHU scoring system can reflect the severity of OLP patients with hyperemia and ulceration lesions more accurately and sensitively compared with other score systems, which provides the potential to be widely used.

Group 1 and 3 innate lymphoid cells are increased in oral lichen planus and oral lichenoid lesions.

OBJECTIVES: Innate lymphoid cells (ILCs) are vital innate immune cells cooperating with T cells. While their phenotypes and functions in oral mucosa kept unclear yet. In the present study, the relative proportions and distribution of different ILC subsets in oral mucosa of oral lichen planus (OLP), oral lichenoid lesions (OLL), and controls were compared. SUBJECTS AND METHODS: Oral mucosal samples were collected from control (n = 29), OLP (n = 20), and OLL (n = 22) donors. ILCs subsets were characterized in single-cell suspensions by flow cytometry. Immunohistochemistry was performed to locate the CD127+ cells in situ. RESULTS: ILCs were present in healthy and increased infiltration in OLP/OLL (p = 0.0092, p = 0.0216). Infiltration of ILC1 increased in OLP/OLL mucosa (p = 0.0225, p = 0.0399), as did the infiltration of ILC3 increase in OLL mucosa (p = 0.0128). The ILC2/ILCs ratio was significantly reduced in OLP and OLL (p = 0.0124, p = 0.0346). CD127+ cells were mainly located closely at the basement membrane. CONCLUSIONS: The results of increased ILC1, decreased ILC2, and increased ILC3 suggested that changes of ILC distributions in oral mucosa may be relevant to persistent inflammation in local tissues, by promoting immune factors and weakening repair capacity.

Advances in comprehensive multidisciplinary treatment for burning mouth syndrome / 口腔疾病防治

@#Burning mouth syndrome (BMS) is a chronic oral and facial pain disorder characterized by burning pain in the oral mucosa, with multiple pathogenic factors including psychosocial, neuropathological, endocrine, and immune factors. There is still a lack of effective treatment options that have been demonstrated to work. With the development of research on the pathogenesis and treatment of BMS, multidisciplinary comprehensive treatment has gradually been introduced and become a new trend of diagnosis and treatment. Before multidisciplinary treatment, it is necessary to go through a full and comprehensive diagnosis and analysis, select the best comprehensive treatment plan, take the diagnosis and treatment of stomatology as the basis and premise, and apply other multidisciplinary combined treatment, including the treatment of concurrent diseases, psychological interventions, correction of bad habits, etc. A combination of laser therapy and psychological intervention is a more effective treatment method among the current treatment methods, with high comfort and good acceptance by patients. If necessary, mecobalamin tablets, clonazepam α-lipoic acid and other drugs can be used to nourish nerves and provide symptomatic treatment. The comprehensive multidisciplinary treatment of BMS is expected to become a new trend and provide a new strategy for improving the therapeutic effect.

Macrophages in intestinal fibrosis and regression.

Intestinal macrophages are heterogenous cell populations with different developmental ontogeny and tissue anatomy. The concerted actions of intestinal macrophage subsets are critical to maintaining tissue homeostasis. However, the dysregulation of macrophages following tissue injury or chronic inflammation could also lead to intestinal fibrosis, with few treatment options in the clinic. In this review, we will characterize the features of intestinal macrophages in light of the latest advances in lineage tracing and single-cell sequencing technology. The roles of macrophages in distinct stages of intestinal fibrosis would be also elaborated. Finally, based on the reciprocal interaction between macrophages and intestinal fibrosis, we will propose the potential macrophage targeting anti-intestinal fibrosis therapies.

[Correlation between low expression of Hsp90 protein in keratinocytes and the number of small extracellular vesicles and its potential clinical significance].

PURPOSE: To investigate the correlation between the level of heat shock protein 90(Hsp90) and the amount of small extracellular vesicles(sEVs) in keratinocytes. METHODS: Human keratinocytes(HaCaT) were cultured in vivo and divided into wild-type group, short hairpin RNA interference group (shRNA group, low expression of Hsp90), and 17-Allylamino-17-demethoxygeldanamycin group (17-AAG group, Hsp90 protein inhibitor). sEVs were isolated from culture system by ultracentrifugation, and their morphological characteristics were observed under transmission electron microscopy (TEM). Western blotting was applied to identify the biological characteristics of sEVs. The number of sEVs particles was detected by nanoparticle tracking analysis (NTA). GraphPad Prism8.0 software was used to analyze the difference in the number of sEVs among the groups by t test (non-parametric Mann-Whitney U test). RESULTS: HaCaT-derived sEVs, obtained by ultracentrifugation, were consistent with the criteria of morphological and biological identification. No expression of Hsp90 protein was detected in HaCaT-derived sEVs. When interfered with Hsp90-shRNA, the number of sEVs were significantly increased. On day 5, the sEVs number of shRNA-interfering group was (177.4±4.18)×108(n=3), while that of vector group was (82.34±4.83)×108(n=3), and the difference was statistically significant (P＜0.0001). After 5 days of inhibition with 17-AAG, the sEVs number of 17-AAG group was （652.5±26.73）×108(n=3) and that of control group was (262.22±5.44)×108(n=3), the difference was statistically significant (P＜0.000 1). CONCLUSIONS: Low expression of Hsp90 protein can promote the secretion of sEVs in HaCaT cells. sEVs may be involved in the transfer of molecules between epithelial cells and immune cells.