Comparison of epidermal growth factor expression and secretion in human salivary glands.

OBJECTIVE: To investigate the expression and secretion of epidermal growth factor (EGF) in major and minor salivary gland tissues of human subjects and to examine the potential influence of sex and age on EGF expression and secretion. DESIGN: Saliva samples from the oral cavity at rest and after citric acid stimulation, as well as serum samples, were collected from 150 healthy subjects, and the concentrations of EGF were measured with enzyme-linked immunosorbent assay (ELISA) and compared. The expression of EGF mRNA and protein in normal salivary gland tissues was measured by real-time polymerase chain reaction (RT-PCR), Western blot (WB), and immunohistochemistry (IHC). RESULTS: The EGF concentration in acid-stimulated saliva was significantly higher than that in resting saliva (P < 0.001), and significantly higher than that in serum (P < 0.001). No sex difference was observed in EGF levels of whole saliva and serum, whereas the EGF levels in saliva and serum were decreased with age (P < 0.001 and P < 0.001, respectively). The EGF concentration and compound secretion rate (CSR) in resting submandibular glands saliva were significantly higher than those in resting parotid glands saliva (P = 0.002 and P < 0.001, respectively). The EGF was expressed in all major and minor salivary glands and ranked in order of submandibular, parotid, sublingual, and labial glands. CONCLUSION: All salivary glands have the function of secreting EGF, and the submandibular gland is the main source of salivary EGF. Aging is a factor influencing the expression and secretion of EGF.

Identification of circRNAs expression profiles and functional networks in parotid gland of type 2 diabetes mouse.

BACKGROUND: Circular RNAs (circRNAs) are a novel kind of non-coding RNAs proved to play crucial roles in the development of multiple diabetic complications. However, their expression and function in diabetes mellitus (DM)-impaired salivary glands are unknown. RESULTS: By using microarray technology, 663 upregulated and 999 downregulated circRNAs companied with 813 upregulated and 525 downregulated mRNAs were identified in the parotid glands (PGs) of type2 DM mice under a 2-fold change and P < 0.05 cutoff criteria. Gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analysis of upregulated mRNAs showed enrichments in immune system process and peroxisome proliferator-activated receptor (PPAR) signaling pathway. Infiltration of inflammatory cells and increased inflammatory cytokines were observed in diabetic PGs. Seven differently expressed circRNAs validated by qRT-PCR were selected for coding-non-coding gene co-expression (CNC) and competing endogenous RNA (ceRNA) networks analysis. PPAR signaling pathway was primarily enriched through analysis of circRNA-mRNA networks. Moreover, the circRNA-miRNA-mRNA networks highlighted an enrichment in the regulation of actin cytoskeleton. CONCLUSION: The inflammatory response is elevated in diabetic PGs. The selected seven distinct circRNAs may attribute to the injury of diabetic PG by modulating inflammatory response through PPAR signaling pathway and actin cytoskeleton in diabetic PGs.

Diagnosis and Treatment of Radioactive Iodine-Induced Sialadenitis: A 10-Year Endoscopic Experience.

OBJECTIVES: The aim of this study was to explore the endoscopic characteristics of radioactive iodine-induced sialadenitis (RAIS), and to evaluate the treatment outcomes of endoscopic intervention for RAIS. STUDY DESIGN: Retrospective case series. METHODS: Eighty-two consecutive patients (11 males and 71 females) diagnosed as RAIS from Nov. 2012 to Sep. 2023 were retrospectively included. All patients underwent endoscopic exploration and intervention of the affected glands. The endoscopic features were collected, and treatment outcomes were followed-up and evaluated through post to pre-operative comparisons of gland status. RESULTS: Overall, endoscopic procedures were undertaken for 162 parotid glands (PGs) and 62 submandibular glands (SMGs). Endoscopy showed severe lumen stricture (49.3%) and ductal atresia (23.5%) in PGs, as well as severe stenosis of the anterior duct and ectasia of the proximal duct (59.7%) in SMGs. During a median six months' follow-up, the treatment outcomes of PGs were evaluated as "improvement" in 23.4%，"lesion maintenance" in 45.1% and "lesion aggravation" in 31.5% of the glands. As for SMGs, the treatment outcomes were scored as "improvement"in 29.0%，"lesion maintenance"in 54.8%, and"lesion aggravation"in 16.1% of the glands. No significant differences of treatment outcomes were found relative to RAI treatment sessions and cumulative dosage. CONCLUSION: RAIS is characteristic of severe lumen stricture and ductal atresia in PGs, and stenosis of the distal duct and ectasia of the proximal duct in SMGs. Endoscopy can alleviate clinical symptoms of RAIS and help to preserve the gland function. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

Direct visualization of intraparotid facial nerve assisting in parotid tumor resection.

Precise recognition of the intraparotid facial nerve (IFN) is crucial during parotid tumor resection. We aimed to explore the application effect of direct visualization of the IFN in parotid tumor resection. Fifteen patients with parotid tumors were enrolled in this study and underwent specific radiological scanning in which the IFNs were displayed as high-intensity images. After image segmentation, IFN could be preoperatively directly visualized. Mixed reality combined with surgical navigation were applied to intraoperatively directly visualize the segmentation results as real-time three-dimensional holograms, guiding the surgeons in IFN dissection and tumor resection. Radiological visibility of the IFN, accuracy of image segmentation and postoperative facial nerve function were analyzed. The trunks of IFN were directly visible in radiological images for all patients. Of 37 landmark points on the IFN, 36 were accurately segmented. Four patients were classified as House-Brackmann Grade I postoperatively. Two patients with malignancies had postoperative long-standing facial paralysis. Direct visualization of IFN was a feasible novel method with high accuracy that could assist in recognition of IFN and therefore potentially improve the treatment outcome of parotid tumor resection.

Diagnostic value of a novel salivary gland ultrasound scoring system in IgG4-related sialadenitis.

OBJECTIVES: To develop a novel ultrasound scoring system for the major salivary glands in patients with immunoglobulin G4-related sialadenitis (IgG4-RS) and assess its diagnostic value in a multicenter cohort of Chinese patients. METHODS: Twenty clinicians (rheumatologists, stomatologists, and radiologists) participated. The study was conducted in four steps: (1) defining the ultrasonography (US) elements, (2) developing a novel ultrasound scoring system for US of the salivary glands, (3) evaluation of inter- and intra-reader reliabilities using the new ultrasound scoring system, and (4) assessing the diagnostic value of this novel ultrasound scoring system in IgG4-RS patients in a Chinese multicenter cohort. RESULTS: A novel ultrasound scoring system for the salivary glands was developed, with total scores ranging from 0 to 34. The inter- and intra-reader reliabilities of the ultrasound scoring system were excellent (0.972 and 0.940, respectively). A total of 470 people were recruited in this study; 187 patients were diagnosed with IgG4-RS, and the remaining 283 people were diagnosed with non-IgG4-RS. Patients with IgG4-RS had significantly higher US scores than the non-IgG4-RS group (mean US score=16 vs. 4, P < 0.001). The calculated area under the curve (AUC) for the total US score was 0.852 (95% CI: 0.814-0.891). The total US scores≥9 showed a sensitivity of 75.4% and a specificity of 91.9%. Association analysis showed a positive correlation between total US scores and serum IgG4 levels and hypocomplementemia (r=0.221, r=0.349; P = 0.002) and a negative correlation between total US scores and serum C3 and C4 levels (r=-0.210, r=-0.303; P = 0.005, P < 0.001). CONCLUSIONS: A novel semiquantitative ultrasound scoring system for patients with IgG4-RS was developed, with good diagnostic performance. The inter- and intra-reader reliabilities were excellent. US scores were correlated with IgG4, C3, and C4 levels and hypocomplementemia.

Salivary Gland Transplantation as a Promising Approach for Tear Film Restoration in Severe Dry Eye Disease.

With increased awareness of dry eye disease (DED), a multitude of therapeutic options have become available. Nevertheless, the treatment of severe DED remains difficult. In a patient whose DED is related to the loss of lacrimal function without severe destruction of the salivary glands, autologous transplantation of the latter as functioning exocrine tissue to rebuild a stable tear film is an attractive idea. All three major and minor salivary glands have been used for such transplantation. Due to the complications associated with and unfavorable prognosis of parotid duct and sublingual gland transplantation, surgeons now prefer to use the submandibular gland (SMG) for such procedures. The transplantation of the SMG not only has a high survival rate, but also improves dry eye symptoms and signs for more than 20 years post-surgery. The regulation of the secretion of the transplanted SMG is critical because the denervated SMG changes its mechanism of secretion. Innovative procedures have been developed to stimulate secretion in order to prevent the obstruction of the Wharton's duct and to decrease secretion when postoperative "epiphora" occurs. Among the minor salivary glands, the transplantation of the labial salivary glands is the most successful in the long-term. The measurement of the flow rates of minor salivary glands and donor-site selection are critical steps before surgery.

Long-Term Outcomes after Pediatric Mandibular Reconstruction Using Vascularized Free Fibula Flap.

BACKGROUND: The purpose of this study was to evaluate the long-term outcomes of mandibular reconstruction with vascularized free fibula flap in pediatric patients. METHODS: Consecutive cases of mandibular reconstruction with vascularized free fibula flaps in pediatric patients at Peking University School and Hospital of Stomatology between 1999 and 2019 were reviewed. Postoperative computed tomography (CT) data of all patients were collected at each postoperative follow-up point, and after the age of 18 years. The length and height of the grafted fibula and the length of the remaining mandible were evaluated by measuring the three-dimensional CT data using ProPlan CMF 3.0 software. Lower limb function was evaluated using the Enneking evaluation scale. Facial symmetry was self-evaluated and scored. Statistical analysis was performed on the data obtained. RESULTS: Fourteen patients were included in this study. All flaps were successful. The CT measurement results showed growth in the length of the grafted fibula that reconstructed the mandibular ramus and the residual mandible ( P < 0.05). The height of the grafted fibula remained stable ( P > 0.05). Eight patients were followed up until they were older than 18 years, and the CT measurement results after 18 years showed an essentially symmetric mandible profile ( P > 0.05). All patients were satisfied with their postoperative facial symmetry. Enneking evaluation scores showed good recovery of lower limb functions. CONCLUSIONS: The vascularized free fibula flap for mandibular reconstruction in pediatric patients is safe and reliable. It also provides good cosmetic and functional outcomes, as it demonstrated positive growth. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The role and mechanism of tight junctions in the regulation of salivary gland secretion.

Tight junctions (TJs) are cell-cell interactions that localize at the most apical portion of epithelial/endothelial cells. One of the predominant functions of TJs is to regulate material transport through paracellular pathway, which serves as a selective barrier. In recent years, the expression and function of TJs in salivary glands has attracted great interest. The characteristics of multiple salivary gland TJ proteins have been identified. During salivation, the activation of muscarinic acetylcholine receptor and transient receptor potential vanilloid subtype 1, as well as other stimuli, promote the opening of acinar TJs by inducing internalization of TJs, thereby contributing to increased paracellular permeability. Besides, endothelial TJs are also redistributed with leakage of blood vessels in cholinergic-stimulated submandibular glands. Furthermore, under pathological conditions, such as Sjögren's syndrome, diabetes mellitus, immunoglobulin G4-related sialadenitis, and autotransplantation, the integrity and barrier function of TJ complex are impaired and may contribute to hyposalivation. Moreover, in submandibular glands of Sjögren's syndrome mouse model and patients, the endothelial barrier is disrupted and involved in hyposecretion and lymphocytic infiltration. These findings enrich our understanding of the secretory mechanisms that link the importance of epithelial and endothelial TJ functions to salivation under both physiological and pathophysiological conditions.

Imaging-based diagnosis and classification of radioactive iodine-induced sialadenitis.

OBJECTIVES: To establish an inflammation grading system for radioactive iodine-induced sialadenitis (RAIS) based on spiral computed tomography (CT), ultrasonography and sialography. METHODS: In all, 120 RAIS patients (18 males and 102 females) were retrospectively included. Spiral CT, ultrasonography and sialography appearances were analysed and categorized as follows: grade I, approximately normal or mild sialadenitis; grade II, moderate sialadenitis; and grade III, severe sialadenitis. Adenitis severity was analysed relative to sex, age, RAI treatment sessions and cumulative doses. RESULTS: Spiral CT showed heterogeneous (78.9%) and atrophic changes (36.8%) in the parotid glands (PGs) and duct ectasia (24.8%) in the submandibular glands (SMGs). Ultrasonography showed heterogeneous echogenicity (54.3%) and diminished gland size (30.2%) in PGs and duct ectasia in SMGs (34.7%). Sialography showed duct obliteration in 25.3% PGs and 3.2% SMGs. Statistical analysis showed good consistency among the three imaging grading results. The incidence and severity of PG lesions were significantly higher than that of SMGs (p < 0.001). As for PGs, adenitis severity was associated with both treatment sessions and cumulative doses; but in SMGs, disease severity was only related to treatment sessions. CONCLUSIONS: A grading system for severity of RAIS was established based on spiral CT, ultrasonography and sialography appearances.

SHED-exos promote saliva secretion by suppressing p-ERK1/2-mediated apoptosis in glandular cells.

OBJECTIVES: Confirm that stem cells from human exfoliated deciduous teeth-derived exosomes (SHED-exos) can limit inflammation-triggered epithelial cell apoptosis and explore the molecular mechanism. METHODS: SHED-exos were injected into the submandibular glands (SMGs) of non-obese diabetic (NOD) mice, an animal model of Sjögren's syndrome (SS). Cell death was evaluated by western blotting and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling staining. RESULTS: SHED-exos treatment promoted the saliva flow rates of NOD mice, accompanied by decreased cleaved caspase-3 levels and apoptotic cell numbers in SMGs. SHED-exos inhibited autophagy, pyroptosis, NETosis, ferroptosis, necroptosis and oxeiptosis marker expression in SS-damaged glands. Mechanistically, Kyoto Encyclopedia of Genes and Genomes analysis of exosomal miRNAs suggested that the rat sarcoma virus (RAS)/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway might play an important role. In vivo, the expression of Kirsten RAS, Harvey RAS, MEK1/2 and p-ERK1/2 was upregulated in SMGs, and this change was blocked by SHED-exos treatment. In vitro, SHED-exos suppressed p-ERK1/2 activation and increased cleaved caspase-3 and apoptotic cell numbers, which were induced by IFN-γ. CONCLUSION: SHED-exos suppress epithelial cell death, which is responsible for promoting salivary secretion. SHED-exos inhibited inflammation-triggered epithelial cell apoptosis by suppressing p-ERK1/2 activation, which is involved in these effects.

Confirmation of eosinophilic sialodochitis by terminal duct biopsy.

OBJECTIVE: To analyse the histopathological features of eosinophilic sialodochitis by using terminal duct biopsy. METHODS: Sixty-five patients with suspected eosinophilic sialodochitis and four with chronic obstructive sialadenitis were prospectively enrolled. Clinical features, laboratory tests and sialograms were comparatively analysed. Terminal duct biopsy of the parotid or submandibular glands was performed concomitantly with endoscopy-assisted duct dilatation to determine the histopathological features of eosinophilic sialodochitis. RESULTS: Based on eosinophil quantification, the samples of suspected patients were scored as 'definite', 'highly suspected' and 'negative' in 26 (40%), 15 (23.1%) and 24 (36.9%) cases, respectively. Gland types and peripheral blood eosinophil counts were significantly different among these three groups. The proportions of itching glands, mucus plug exudations and elevated immunoglobulin E levels were higher in the 'definite' group than in the other two groups; however, the intergroup differences were insignificant. The primary pathological features of eosinophilic sialodochitis were abundant eosinophils and lymphocytes infiltrated around the duct, degranulation of eosinophils, extensive fibrosis and scattered mastocytes. Periductal eosinophils were not found in cases of chronic obstructive sialadenitis. CONCLUSION: Our findings suggest that terminal duct biopsy is safe and valuable for the pathological confirmation of eosinophilic sialodochitis, and can be used simultaneously with endoscopy-assisted duct dilatation.

Symmetrical Midfacial Growth After Pediatric Mandibular Reconstruction With Free Fibula Flap.

BACKGROUND: Free fibula is the workhorse flap for mandibular reconstruction and is increasingly being used in pediatric patients. However, craniomaxillofacial growth and development involve interdependent processes, and it remains unknown whether mandibular reconstruction with free fibula allows symmetric growth of the midface. PURPOSE: The study evaluated midfacial symmetry after pediatric mandibular defect reconstruction. STUDY DESIGN, SETTING, SAMPLE: This retrospective cohort study included pediatric patients aged ≤14 years who underwent mandibular reconstruction with free fibula flap. Postoperative computed tomography data were obtained at predefined follow-up time points. Midfacial symmetry was evaluated based on 3-dimensional (3D) cephalometry. PREDICTOR VARIABLE: The predictor variable was the side of the midface (affected or healthy side relative to the mandibular defect). MAIN OUTCOME VARIABLES: The primary outcome variable was postoperative midfacial symmetry (at 1 week, 6 months, 1 year, 2 years, and >3 years, or after the age of 18 years), assessed in horizontal, vertical, and anteroposterior dimensions using 3D cephalometry. Another outcome variable was patient satisfaction based on a self-evaluation using visual analog scoring. COVARIATES: Sex, age, diagnosis, and type of denture restoration. ANALYSES: Paired t tests were performed to assess the relationship between the predictor and outcome variables, with the significance level of P < .05. RESULTS: A total of 13 patients were included in this study (9 males and 4 females; mean age: 12.23 ± 2.39 years). The average distance from upper first molar point (U6) to the horizontal plane on the affected side became greater than on the healthy side (difference: 0.7 ± 0.5 mm to 1.6 ± 1.4 mm, P < .05), while the average distance from pterygomaxillary fissure to coronal plane on affected side became shorter than that on the healthy side (difference: 0.6 ± 0.6 mm to 1.2 ± 1.1 mm, P < .05) from 1 year after the surgery. There were no statistically significant differences in the remaining measurements between the 2 sides (P > .05). All the patients were satisfied with their postoperative facial symmetry. CONCLUSIONS AND RELEVANCE: There were no severe midface deformities after pediatric mandibular reconstruction with free fibula flap. Meanwhile, pediatric mandibular reconstruction and proper occlusion could promote midfacial growth and symmetry.

Silencing of peroxiredoxin III inhibits formaldehyde-induced oxidative damage of bone marrow cells in BALB/c mice.

BACKGROUND: Formaldehyde (FA) is associated with the occurrence of leukemia, and oxidative stress is considered to be a major reason. As an endogenous biomarker of oxidative stress, few studies focus on the relationship between peroxiredoxin III (PrxIII) and FA toxicity. Our previous research observed high expression of PrxIII occurred in the process of apoptosis of bone marrow cells (BMCs) induced by FA, however the exact mechanism is unclear. Therefore, this paper aimed to explore the possible association between FA toxicity and PrxIII gene. METHODS: We first, used a Cell Counting Kit-8 (CCK-8) to detect the viability of BMCs after they were exposed to different doses of FA (50, 100, 200 µmol/L) for different exposure time (12, 24, 48 h), then chose 24 h as an exposure time to detect the expression of PrxIII for exposing different doses of FA by Quantitative reverse transcription-PCR (qRT-PCR) and Western blot analysis. Based on our preliminary experimental results, we chose 100 µmol/L FA as an exposure dose to expose for 24 h, and used a small interfering RNA (siRNA) to silenced PrxIII to examine the cell viability by CCK-8, reactive oxygen species (ROS) level by DCFH-DA, apoptosis by Annexin V/PI double staining and cell cycle by flow cytometry (FCM) so as to explore the possible regulatory effect of PrxIII silencing on FA-induced bone marrow toxicity. RESULTS: High expression of PrxIII occurred in the process of FA-induced oxidative stress. Silencing of PrxIII prevented FA from inducing oxidative stress, thus increasing cell viability, decreasing ROS level, rescuing G0 -G1 and G2 -M arrest, and reducing cell apoptosis. CONCLUSION: PrxIII silencing might be a potential target for alleviating FA-induced oxidative damage.

Characteristics and management of vascular compromise after an organ transplantation surgery of the head and neck region: Analysis of 220 submandibular glands with autologous transplantation.

BACKGROUND: Microvascular submandibular gland transplantation (SMGT) for severe dry eye disease (DED) has rarely been reported in the literature. The aim of this study was to report a case series of SMGT with the special focus on monitoring and management of postoperative vascular compromise. METHODS: Using a retrospective single-cohort study design, the investigators enrolled a sample of DED patients undergoing SMGT in a Chinese university hospital during 1999 and 2021. The main outcomes were baseline and surgical data, post-operative manifestations, and surgical results. Descriptive, uni- and bivariate statistics were computed with the significant P < 0.05. RESULTS: During the study period, 220 DED patients (55.9% female) with a mean age of 32.66±14.47 years underwent SMGT. Vascular compromises occurred in 27 grafted glands (12.3%; 22 venous compromises and 5 arterial compromises) at a median of 27 h(range, 3.3 to 288 h) after surgery. Harden texture and swelling of the covering skin flap of the donor indicated venous compromises, while some specific sign was absent for arterial compromise. The accompanying vein of the facial artery (FAV) as a donor's vein was associated with less vascular compromise compared to the anterior facial vein (AFV). Timely reexploration was performed in 25 glands (92.6%), with a salvaged rate of 48%, and more venous compromises were salvaged compared to artery compromises (54.6% vs. 0%, P = 0.047). Temporary hypersecretion on postoperative 2-5 days was noticed in the grafted glands with no or salvaged vascular compromise (Schirmer's test, 35 mm/5 min and 37 mm/5 min, respectively, P = 0.749), while they were absent for the 15 surgically failed grands (Schirmer's test 0 mm/5 min, P<0.001). CONCLUSIONS: Vascular compromise appears to be a common complication of SMGT. Postoperative hypersecretion of the grafted glands may indicate good circulation, and the use of FAV as the donor's vein could help to decrease the risk of vascular compromise.

Facial Reanimation After Peripheral Facial Nerve Paralysis: A Single-institution Surgical Experience.

Facial nerve trauma occasionally develops during oral and maxillofacial surgery. This study was aimed at enhancing the available knowledge on facial nerve reanimation correlated to surgery and proposing our surgical algorithm. We retrospectively analyzed medical records of patients who underwent facial reanimation surgery at our hospital. The inclusion criterion was surgery for facial reanimation from January 2004 to June 2021. We included 383 eligible patients who underwent facial reanimation surgery. Trauma or maxillofacial neoplasms were noted in 208 of 383 and 164 of 383 cases, respectively. In 238 of 383 cases, nerve branches were likely more vulnerable. Facial nerve anastomosis was performed in 256 patients. Sixty-eight patients received nerve grafts. In 22 patients, distal facial nerve transfer to the masseteric nerve, sublingual nerve, or contralateral facial nerve was performed. Twenty-five patients received static surgery; in most cases, the temporalis fascia flap (20/25) was used. The nerve function outcomes were HB grade I (n=17), Grade Ⅱ (n=108), Grade Ⅲ (n=118), Grade Ⅳ (n=94), and Grade V (n=46). The mean follow-up time was 4.88 ± 3.93 years. Facial paralysis caused by trauma ( P =0.000), branch injury ( P =0.000), and the primary reconstruction of facial nerve ( P =0.000) were predictive of favorable treatment outcomes. Although facial nerve injury caused by trauma was more likely, cases of interference in facial expression could be limited, and so did the injury to branches. Nerve anastomosis was prioritized if a tension-free suture was possible. Maintaining the integrity of the nerve and shortening the duration of mimetic muscular denervation were crucial.

SHED-derived exosomes ameliorate hyposalivation caused by Sjögren's syndrome via Akt/GSK-3ß/Slug-mediated ZO-1 expression.

BACKGROUND: Sjögren's syndrome (SS) is an autoimmune disorder characterized by sicca syndrome and/or systemic manifestations. The treatment is still challenging. This study aimed to explore the therapeutic role and mechanism of exosomes obtained from the supernatant of stem cells derived from human exfoliated deciduous teeth (SHED-exos) in sialadenitis caused by SS. METHODS: SHED-exos were administered to the submandibular glands (SMGs) of 14-week-old non-obese diabetic (NOD) mice, an animal model of the clinical phase of SS, by local injection or intraductal infusion. The saliva flow rate was measured after pilocarpine intraperitoneal injection in 21-week-old NOD mice. Protein expression was examined by western blot analysis. Exosomal microRNA (miRNAs) were identified by microarray analysis. Paracellular permeability was evaluated by transepithelial electrical resistance measurement. RESULTS: SHED-exos were injected into the SMG of NOD mice and increased saliva secretion. The injected SHED-exos were taken up by glandular epithelial cells, and further increased paracellular permeability mediated by zonula occluden-1 (ZO-1). A total of 180 exosomal miRNAs were identified from SHED-exos, and Kyoto Encyclopedia of Genes and Genomes analysis suggested that the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) pathway might play an important role. SHED-exos treatment down-regulated phospho-Akt (p-Akt)/Akt, phospho-glycogen synthase kinase 3ß (p-GSK-3ß)/GSK-3ß, and Slug expressions and up-regulated ZO-1 expression in SMGs and SMG-C6 cells. Both the increased ZO-1 expression and paracellular permeability induced by SHED-exos were abolished by insulin-like growth factor 1, a PI3K agonist. Slug bound to the ZO-1 promoter and suppressed its expression. For safer and more effective clinical application, SHED-exos were intraductally infused into the SMGs of NOD mice, and saliva secretion was increased and accompanied by decreased levels of p-Akt/Akt, p-GSK-3ß/GSK-3ß, and Slug and increased ZO-1 expression. CONCLUSION: Local application of SHED-exos in SMGs can ameliorate Sjögren syndrome-induced hyposalivation by increasing the paracellular permeability of glandular epithelial cells through Akt/GSK-3ß/Slug pathway-mediated ZO-1 expression.

Vascularized Free Fibular Flap in Oral and Maxillofacial Reconstruction: A 20-year Experience at a Single Institution Using 2640 Flaps.

BACKGROUND: This retrospective study reviewed all patients who underwent oral and maxillofacial reconstruction with fibular flaps in the last 2 decades at a single hospital. MATERIALS AND METHODS: We reviewed all patients with fibular flaps from 1999 to 2018. The following data were collected: sex; age; reconstruction region; diagnosis; the number of days spent in the hospital after surgery; time spent using a tourniquet for harvesting a fibula flap; vessels at the recipient site; the prevalence of unplanned reoperations; the prevalence of flap failure; history of preoperative radiotherapy; virtual surgical planning; segments of the fibula. RESULTS: In total, 2640 patients were included. The mean age was 45.5 years. The most prevalent region of reconstruction was the mandible (n=2347, 88.9%). The most common diagnosis was squamous cell carcinoma (n=1057, 40.0%). The mean number of days spent in the hospital after surgery decreased year-by-year from 18.3 days to 10.4 days. The first choice of recipient artery was the facial artery (n=1643, 62.2%) and that of the recipient vein was the external jugular vein (n=1196, 45.3%). The prevalence of surgical success was 97.6%. Prevalence of unplanned reoperations was 7.5%. CONCLUSIONS: The fibular flap was a good choice for oral and maxillofacial bony reconstruction in most cases.

Establishment of a Beagle Dog Model of Dry Eye Disease.

Purpose: To establish a Beagle dog model of dry eye disease (DED). Methods: DED models were induced by surgical removal of orbital lacrimal glands and entire resection of third eyelids in the left eyes of six Beagle dogs. Intact right eyes served as self-controls. Non-anaesthetized Schirmer test (STT), tear break-up time (TBUT), and fluorescein staining grading were performed monthly after operation. Interleukin (IL)-1ß, IL-8, IL-10, and tumor necrosis factor-α (TNF-α) levels were detected in tears and conjunctiva tissues. Six months after surgery, conjunctiva and cornea were collected and histopathologically analyzed. Results: Signs of DED appeared within one month after surgery and then remained stable. STT values were significantly reduced by 88% within 3 weeks after operation and remained stable over months with 1.6 ± 0.4 mm. Mean TBUT decreased significantly within two months after operation and maintained 5.2 ± 1.1 seconds. The mean fluorescein staining score was highest at the first month and then was reduced, eventually reaching a balance with 11.0 ± 1.3 points. Elevated levels of IL-1ß, IL-8, IL-10, and TNF-α were detected in tears and conjunctivas of operated eyes. Hematoxylin and eosin staining showed cornea neovascularization in the corneal stroma with thickened stroma layer and disorganized collagen bundles. Periodic acid-Schiff staining revealed a reduced function of conjunctival goblet cells. Conclusions: A combined type of DED model on the Beagle dog was established by removal of the orbital lacrimal gland and resection of the third eyelid. This DED model is easily accessible and is stable at six-month observation. Translational Relevance: The surgery-induced Beagle dog DED model is easily accessible and stable over a relatively long time.