Morphological characteristics of submandibular glands of miniature pig

Background Miniature pig （minipig） is increasingly used as a large animal model for a variety of biomedical studies. Little information is available in the literature on anatomy, histology and sialogragh of the submandibular gland of the minipig. The purpose of this study was to characterize the morphology of a miniature pig＇s （minipig） submandibular gland as a large animal model for further biomedical studies. Methods Five minipigs were subjected to sialographic, anatomic, histologic, histochemical and uhrastructural evaluations for submandibular glands. Results Sialograms showed a long, horizontal main excretory duct and a pear-shaped gland located inferoposterior to the angle of the mandible. The submandibular glands lied superficial to the suprahyoid, and infrahyoid muscle groups, and were covered by the inferior portion of the parotid gland. The submandibular glands were characterized by a mixed parenchyma of mucous and serous secretory aeini. Alcian blue （AB） staining and periodic acid-Schiff （PAS） reactions demon-strated that minipig submandibular glands synthesized and secreted acid mucous substances by serous cells and polysaccharide, and neutral mucous substances, by mucous cells. Conclusion The submandibular gland of the minipig is considered a useful large salivary gland animal model for biomedical studies.

Anatomy of arteries and veins of submandibular glands

Background Transplanting a vascularized autologous submandibular gland （SMG） is considered an effective method to treat severe keratoconjunctivitis sicca. But the operation may fail due to the anatomic variances in the blood vessels of SMG. The present study aimed to investigate the submandibular glands at the microanatomy level. Methods The microanatomy of blood vessels including arteries and veins of submandibular gland was investigated using 30 adult corpses and 60 submandibular glands were anatomized under a surgical microscope. The lengths and diameters of the arterial and venous glandular branches were measured using sliding caliper. Results The submandibular gland was mainly supplied by the facial artery and submental artery, partly by the lingual artery and external jugular artery. The venous drainage of the submandibualr gland occurred through the anterior facial vein, the venae comitantes of facial artery, the vein close to the Whaston＇s duct （the hilum vein）, and seldom drained to external jugular vein and other veins. Conclusions The anatomy of SMG is a complicated structure. Determining the main blood vessels of the submandibular gland is very important to achieve a successful vascularized autologous SMG transplant.

Two Cases of Epidermoid Cyst of the Buccal Floor Simulating: A Tumour of the Submandibular Gland

Dermoid cyst of the oral floor is rare benign tumour, who having three histological aspects: dermoid, teratoid and epidermoid. This one is characterized by the presence of a squamous stratified epithelium with cutaneous remnants. It may occur in any part of the body, however their frequency in the ENT sphere is relatively scarce. Seven per cent (7%) only of epidermoid cysts occur in the cervico-facial area, 1.6% of which locate at the floor level. When they are located submandibular, they can pose diagnostic difficulties and look like a tumour of the submaxillary gland. We report two cases of epidermoid cyst of the floor. Both patients suffered from swelling of the submandibular gland. Magnetic Resonance Imaging was not requested due to lack of resources. However, surgery allowed in both cases the excision of a cyst next to a normal submandibular gland. Patients did well post operatively.

Botulinum toxin A inhibits salivary secretion of rabbit submandibular gland

Botulinum toxin A （BTXA） has been used in several clinical trials to treat excessive glandular secretion; however, the precise mechanism of its action on the secretory function of salivary gland has not been fully elucidated. In this study, we aimed to investigate the effect of BTXA on secretion of submandibular gland in rabbits and to identify its mechanism of action on the secretory function of salivary gland. At 12 weeks after injection with 5 units of BTXA, we found a significant decrease in the saliva flow from submandibular glands, while the salivary amylase concentration increased. Morphological analysis revealed reduction in the size of acinar cells with intracellular accumulation of secretory granules that coalesced to form a large ovoid structure. Expression of M3-muscarinic acetylcholine receptor （M3 receptor） and aquaporin-5 （AQP5） mRNA decreased after BTXA treatment, and distribution of AQP5 in the apical membrane was reduced at 1, 2 and 4 weeks after BTXA injection. Furthermore, BTXA injection was found to induce apoptosis of acini. These results indicate that BTXA decreases the fluid secretion of submandibular glands and increases the concentration of amylase in saliva. Decreased expression of M3 receptor and AQP5, inhibition of AQP5 translocation, and cell apoptosis might involve in BTXA-reduced fluid secretion of submandibular lands.

Bone marrow-derived mesenchymal stem cells migrate to healthy and damaged salivary glands following stem cell infusion

Xerostomia is a severe side effect of radiation therapy in head and neck cancer patients. To date, no satisfactory treatment option has been established. Because mesenchymal stem cells（MSCs） have been identified as a potential treatment modality, we aimed to evaluate stem cell distribution following intravenous and intraglandular injections using a surgical model of salivary gland damage and to analyse the effects of MSC injections on the recruitment of immune cells. The submandibular gland ducts of rats were surgically ligated. Syngeneic adult MSCs were isolated, immortalised by simian virus 40（SV40） large T antigen and characterized by flow cytometry. MSCs were injected intravenously and intraglandularly. After 1, 3 and 7 days, the organs of interest were analysed for stem cell recruitment. Inflammation was analysed by immunohistochemical staining. We were able to demonstrate that, after intravenous injection, MSCs were recruited to normal and damaged submandibular glands on days 1, 3 and 7. Unexpectedly, stem cells were recruited to ligated and non-ligated glands in a comparable manner. After intraglandular injection of MSCs into ligated glands, the presence of MSCs, leucocytes and macrophages was enhanced, compared to intravenous injection of stem cells. Our data suggest that injected MSCs were retained within the inflamed glands, could become activated and subsequently recruited leucocytes to the sites of tissue damage.

Sclerosing polycystic adenosis of the submandibular gland: Two case reports

BACKGROUND Sclerosing polycystic adenosis(SPA)is a rare disease of salivary glands,similar to fibrocystic disease of the breast.It occurs over a wide age range and exhibits a slight female preference.Most SPA cases have occurred in the parotid gland.The exact nature of SPA is unclear,but its tumor nature has recently been proposed.Although SPA has a good prognosis after adequate surgery,atypical lesions might occur,ranging from mild dysplasia to carcinoma in situ in some cases.To the best of our knowledge,only five cases of SPA in the submandibular gland have been reported to date.Here,we present two new cases of SPA involving the submandibular gland.CASE SUMMARY A 50-year-old woman and a 52-year-old woman were referred to Tongji Hospital in Wuhan,China,with complaints of moderate pain,recurrent swelling,and a mass in the submandibular area.After admission,the two cases of the submandibular mass were examined physically.The boundary of the submandibular tumor was clear,and the range of motion was good.After preoperative examinations,surgery was performed on a selective basis.Postoperative histopathological examination revealed a well-defined mass with acinar structures,ducts,or cystic dilated glands of various sizes scattered in a large number of proliferative sclerosing stroma.There were flat and cuboidal cells,and eosinophils in the duct epithelium.There was also a eosinophilic substance in the lumen of dilated cysts.No atypical epithelial hyperplasia,invasive growth,or carcinoma in situ was found.Based on the above findings,the mass was diagnosed as SPA.Both patients have remained asymptomatic and no recurrence or distant metastasis had occurred by the 7-mo and 5-year follow-up,respectively.CONCLUSIONSPA is a rare disease of the salivary gland. Even though it has a good prognosisafter adequate surgery, atypical lesions may occur from mild dysplasia tocarcinoma in situ. However, no recurrence, distant metastasis, or mortality hasbeen reported for submandibular gland SPA. Clinicians and pathologists shouldbe familiar with the characteristics of SPA in the submandibular gland to avoidmisdiagnosis and overtreatment.

Salivary duct carcinoma of the submandibular gland presenting a diagnostic challenge: A case report

BACKGROUND Salivary duct carcinoma(SDC)is a rare,extremely aggressive malignancy that arises in the submandibular gland.It can metastasize locally early and therefore is an important differential diagnosis of metastatic disease in cervical lymph nodes or specific lymphadenitis such as tuberculous cervical lymphadenitis.CASE SUMMARY We report a case of SDC in the submandibular gland that presented diagnostic difficulty.The lesion was coincidentally discovered through examination of the radiolucent area of the maxilla.Imaging failed to confirm the possibility of specific inflammation,leading us to execute an open biopsy to verify the diagnosis.The surgical specimen showed that the submandibular gland was primarily replaced with a calcified body.Following histological analysis and confirmation,we performed surgical resection,radiotherapy,and various chemotherapies.CONCLUSION Radiographic imaging characteristics of lymph node metastases of salivary gland cancer,especially of SDC,may resemble other cervical lymphadenitis;calcification at the submandibular gland is the landmark of SDC occurring at the submandibular gland.

Possible Role of the Submandibular Gland in the Development of Obesity in Mice

The possible role of submandiblular glands (SMG) in the development of obesity was studied in two types of genetically obese mice, ob/ob and yellow Ay: Obesity is caused by hyperplasia followed by hypertrophy in ob/ob mice and mainly by hypertrophy in Ay mice.The histological features of SMGs exhibited clear sexual dimorphism in both mice similarto lean controls. The SMGs of ob/ob mice was smaller in size and had smaller granular convoluted tubular portions than lean controls, while the SMGs of Ay mice did not differ from lean controls. Sialoadenectomy before and after development of obesity gCnerally reduced the gain of body weights in both sexes of Ay mice but not in ob/ob mice. The content of epidermal growth factor (EGF) in the SMGs was higher in Ay mice and lower in ob/ob mice than their controls. The possible role of EGF in the SMGs in the development of obesity is discussed

Changes of norepinephrine and tumor necrosis factor in submandibular gland of rats with sympathetic nerve injury and the protective effect of 17 beta-estradiol

BACKGROUND： Recent researches have indicated that estrogen has extensive neuroprotective effects. So some studies designed ovariectomized animal models and administrated with estrogen, so as to verify its neuroprotective effects. OBJECTIVE： To observe the effect of 17 beta-estradiol on the content of norepinephrine （NE） and level of tumor necrosis factor （TNF） in submandibular glands of rats with sympathetic nerve injury, and analyze the dose-dependence and pathway of action. DESIGN： A randomized control animal study SETTINGS： Department of Hand Surgery, the 252 Hospital of Chinese PLA; Department of Hand Surgery Union Hospital affiliated to Tongji Medical College, Huazhong University of Science and Technology. MATERIALS： Fifty healthy female Wistar rats were randomly divided into 5 groups with 10 rats in each group： sham-operated group, ovariectomy＋6-OHDA＋saline group, ovariectomy＋6-OHDA＋17β-estradiol 50, 200 and 500 μg/kg groups. METHODS： The experiments were carried out in Tongji Medical College, Huazhong University of Science and Technology between October 2005 and March 2006. Bilateral ovaries were only exposed but not resected for the rats in the sham-operated group, but bilateral ovaries were resected in all the other groups. In the ovariectomy＋6-OHDA＋176-estradiol 50, 200 and 500 μg/kg groups, the rats were administrated with intraperitoneal injection of 6-OHDA （8 mg/kg）, and then immediately given 176-estradiol of corresponding dosages respectively, once a day for 10 days continuously. Rats in the sham-operated group and ovariectomy＋6-OHDA＋saline group were administrated with saline of the same volume. After administration, 5 rats in each group were killed to determine the NE contents in bilateral submandibular glands with high performance liquid chromatography-electrochemical detector （HPLC-ECD）, and the other 5 rats were used to determine the TNF levels in submandibular glands with enzyme-linked immunosorbant assay. MAIN OUTCOME MEASURES： The NE contents and TNF levels in submandibular glands of rats in each group were observed. RESULTS： All the 50 rats were involved in the analysis of results. （1） The NE content was obviously lower in the ovariectomy＋6-OHDA＋saline group than in the sham-operated group [（1 035±196）, （1 823±314） ng/g, P 〈 0.05], there were no significant differences between the ovariectomy＋6-OHDA＋17β-estradiol 50 μg/kg group and ovariectomy＋6-OHDA＋saline group [（1 004±253）, （1 035±196） ng/g, P 〉 0.05], but obviously higher in the ovariectomy＋6-OHDA＋17β-estradiol 200 and 500 μg/kg groups than in the ovariectomy＋6-OHDA＋saline group [（1 487±268）, （1 939±274）, （1 035±196） ng/g, P 〈 0.05]. （2） The TNF level was obviously higher in the ovariectomy＋6-OHDA＋saline group than in the sham-operated group [（3.498±0.792）, （1.893±0.533） ng/g, P 〈 0.05], there were no significant differences between the ovariectomy＋ 6-OHDA＋17β-estradiol 50 μg/kg group and ovariectomy＋6-OHDA＋saline group [（3.328 ±0.712）, （3.498±0,792） ng/g, P 〉 0.05], but obviously lower in the ovariectomy＋6-OHDA＋17β-estradiol 200 and 500 μg/kg groups than in the ovariectomy＋6-OHDA＋saline group [（2.639±0.438）, （2.016±0.619）, （3.498＋0.792） ng/g, P 〈 0.05]. CONCLUSION： Estrogen has obvious protective effect dose-dependently on 6-OHDA induced chemical sympathetic nerve terminal injury in rats, and it may play its protective role by reducing TNF level and ameliorating inflammatory reaction.

Long-term rare giant sialolithiasis for 30 years:A case report and review of literature

BACKGROUND Sialolithiasis is one of the most common salivary gland disorders,most commonly affecting the submandibular gland.Submandibular sialolithiasis can be treated using non-invasive conservative measures and invasive treatments.Treatment selection was based on the ductal system anatomy and the size and location of the stones.This study aimed to review the updates on sialolithiasis treatment and compare the different management strategies of the variables.CASE SUMMARY This report presents a case of a long-term,rare,and giant sialolithiasis within the submandibular gland parenchyma for 30 years in an older adult.Our patient presented with painless right submandibular swelling.Computed tomography revealed a calcified mass measuring 35 mm×20 mm within the right submandibular gland.In this case,the infection and fibrosis of the affected gland and size of the stone did not provide us with other alternatives except for the excision of the involved gland.Thus,right submandibular sialoadenectomy was performed via the transcervical approach.After the surgery,the patient recovered without any complaints,side effects,or complications.CONCLUSION Tailored management is important for preserving gland function,maintaining low risk,and reducing patient discomfort.

Synchronous carcinoma of head and neck: 2 cases report

Multiple primary cancers are becoming an increasingly frequent situation and are often the source of many diagnostic and therapeutic difficulties. We report the case of two patients diagnosed with head and neck synchronous carcinomas. The first case is a 33-yearold man with a history of a keratinizing squamous cell carcinoma of the eye lid and who was operated 4 mo later from a mucoepidermoid carcinoma of thesubmandibular salivary gland. The second case is a 71-year-old woman who underwent a total parotidectomy for a mucoepidermod carcinoma of the left parotid gland and who consulted 2 mo later for epistaxis. The explorations concluded to a squamous cell carcinoma of the nasopharynx. The patient had a complementary radiotherapy. No local neither distant recurrence of the two tumors has been detected after a follow-up of 36 mo in the first case and 24 mo in the second one.

Surgical Removal of a Giant Sialolith by Diode Laser

Giant sialoliths larger than 20 mm are rare. The surgery has to be performed with the minimally invasive method in order to avoid the morbidity associated with the surgical techniques. In this report the surgical removal of a giant sialolith of 25 mm by using diode laser is described. A 57-year-old female was presented with a firm mass in the anterior part of the left side of the floor of the mouth. Following the clinical and radiological examination, the left submandibular duct sialolith was diagnosed. The diode laser was used with a power setting of 810 nm of wavelength, 4.0 W of power, 0.5 ms continuous wave and 1000 Hz of frequency for the incision. The giant sialolith was adequately removed under local anesthesia. The procedure was well-tolerated. The wound healing was uneventful in the postoperative period. By the 10th day after surgery the patient had no complaints and the salivary flow was normal. It was concluded that the use of 810-nm diode laser application is a safe and useful technique. Due to the excellent cutting and coagulation ability, there is a low complication rate, making it an appropriate alternative for this type of surgical procedure.

Establishment of submandibular gland allotransplantation model in miniature swine

Background Autologous transplantation of the submandibular gland （SMG） into the temporal fossa with microvascular anastomosis has been successfully applied in severe xerophthalmia patients as a permanent tear substitute. However, severe xerophthalmia can be accompanied by salivary gland dysfunction, making such autotransplantation unsuitable. Therefore, SMG allotransplantation might be a solution. The aim of this study was to assess the technical feasibility of submandibular gland allotransplantation. Methods Twelve miniature swine were randomized to serve as donors or recipients. One SMG was transplanted between a donor and a recipient. The donor SMG was revascularized by microvascular anastomosis of its vascular pedicle to the recipient lingual artery and external jugular vein. The secretory duct was implanted into the vestibule of the mouth through a subcutaneous tunnel. No ilnmunosuppressive agent was administered. The results were assessed by visual inspection of the secretion, and histopathological examination of the transplanted SMG. Results Technically, all surgical procedures were successful. Clear secretion flowed out of the duct as soon as blood supply of the transplanted submandibular gland was reestablished. The secretion of the gland lasted for 5 days. As expected, an acute rejection reaction occurred after surgery because no immunosuppressive agents were used. Secretion from the transplanted SMG ceased within 5 days. Conclusions A model of SMG allotransplantation can be established in miniature swine. The technique of submandibular gland allotransplantation is feasible.

Effect of Bushen Qingre Yuyin Decoction on Salivary Secretion, Spleen Index, Submandibular Gland Index, Submandibular Gland Histomorphology, and aqp5 Expression in the Nonobese Diabetic Mouse Model

Objective:The objective of this study was to observe the effect of Bushen Qingre Yuyin Decoction on the spleen index,submandibular gland index,salivary secretion,submandibular gland morphology,and aquaporin 5(AQP5)expression levels in the submandibular gland.Materials and Methods:Fifty 8-week-old nonobese diabetic(NOD)female mice were randomly divided into the following five groups:model;hydroxychloroquine;and high-,medium-,and low-dose Bushen Qingre Yuyin Decoction prescription.The blank group consisted of ten 8-week-old Balb/C rats.Bushen Yuyin Qingre Decoction was administered by gavage at 20,40,and 80 g/kg in the low-,medium-,and high-dose groups,respectively.The hydroxychloroquine group was administered hydroxychloroquine at a dose of 80 mg/kg by gavage.The normal and model groups were administered the same amount of saline.After the different administrations,the amount of salivary secretion in the mice was regularly observed.After 12 weeks,the mice were sacrificed,and their submandibular gland tissues were excised,stained with hematoxylin-eosin,and pathologically scored.AQP5 expression levels in the tissues were detected using real-time polymerase chain reaction.Results:The spleen index of mice in the high-dose group was higher than that in the model group(P<0.05),and the submandibular gland index of the hydroxychloroquine group and all the Bushen Qingre Yuyin Decoction prescription groups was higher than that in the model group(P<0.05).After 6 weeks,the salivary volume of the hydroxychloroquine group and all the Bushen Qingre Yuyin Decoction prescription groups was significantly higher than that of the model group(P<0.05);the amount of lymphocyte infiltration in mice among each administration group was significantly reduced(P<0.05);and the AQP5 expression levels in the submandibular glands of mice had significantly increased in the hydroxychloroquine and high-dose groups(P<0.05),with the high-dose group showing the best effect.Conclusion:Bushen Qingre Yuyin Decoction can effectively increase the spleen and submandibular gland indexes of NOD mice,increase the amount of salivary secretion,reduce lymphocyte infiltration in submandibular gland tissue,and significantly increase AQP5 expression levels,which may be positively correlated with the administered dose.

耐瑞特:一种基于群体学习方法的新型硝酸盐制剂,可发挥更好的机体保护作用

硝酸盐是一种机体不可或缺的营养物质,已应用于多种疾病的预防和治疗研究.但由于半衰期短,硝酸盐的临床应用受限.为了提高硝酸盐可用性,突破传统的依赖大规模高通量生物实验的药物配伍研发瓶颈,本文报道了一种基于群体学习方法的药物配伍预测系统,该系统预测维生素C为与硝酸盐配伍的首选药物.通过采用微囊化技术,筛选并优化缓释制剂工艺,以维生素C、硝酸钠及壳聚糖3000为芯材,果胶与羧甲基纤维素钠为壁材制备硝酸盐纳米颗粒,命名为耐瑞特(Nanonitrator).耐瑞特的更长循环期显著提高了硝酸盐对放射性唾液腺损伤的疗效,同时维持了安全性.相同剂量的耐瑞特比硝酸盐(包含或不包含维生素C)可显著增强PI3K-Akt信号通路转导,更好地维持细胞内稳态,提示了其广泛的临床应用潜力.此外,本文还提供了一种将无机化合物加入缓释纳米颗粒的新方法.

SHED-derived exosomes ameliorate hyposalivation caused by Sjögren’s syndrome via Akt/GSK-3b/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 3b(p-GSK-3b)/GSK-3b,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-3b/GSK-3b,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-3b/Slug pathway-mediated ZO-1 expression.