Effects of personalized oral exercises on swallowing function among patients with oral cancer after free flap transplantation: a cluster randomized controlled trial

Dysphagia is a common complication in patients with oral cancer who have undergone free flap transplantation. The aim of this cluster randomized controlled trial was to evaluate the effect of personalized oral exercises on swallowing function in this group of patients. Eligible patients were randomly assigned to the intervention (n = 34) or control (n = 34) group. Intervention group patients received personalized oral exercises starting on day 6 after surgery. Swallowing function was evaluated on days 6 and 15, and at 1 month postoperative using the Mann Assessment of Swallowing Ability-Oral Cancer tool (MASA-OC). On day 15 and at 1 month after surgery, the total MASA-OC score (P = 0.003, P < 0.001) and the mouth opening (P = 0.001, P < 0.001) and lip seal (both P < 0.001) item scores showed a significantly greater improvement in the intervention group than in the control group. Moreover, the changes in salivation (P < 0.001) and tongue movement (P = 0.025) scores at 1 month after surgery were significantly greater in the intervention group than in the control group. There was no significant difference between the groups in the change in tongue strength scores on day 15 or at 1 month postoperative (P = 0.476, P = 0.223). Personalized oral exercises can improve swallowing function in patients with oral cancer after free flap transplantation.

[Delayed diagnosis of oral squamous cell neoplasms at different sites]

OBJECTIVE

To investigate the diagnostic delay of patients with oral squamous cell carcinoma by self-designed questionnaire to find out the significant influencing factors, so as to identify the influencing factors of the patient's delay and the risk of oral cancer.

METHODS

A total of 514 patients with primary oral squamous cell carcinoma were enrolled at Peking University School and Hospital of Stomatology from January 2014 to April 2016, including 334 men and 180 women, with a male to female ratio of 1.85:1. The youngest participant was 21 years old, with a maximum of 89 years and a median age of 57.6 years. The position of the disease according to International Classification of Diseases-10 (ICD-10) was divided into lip, buccal, gingival, retromolar, palate, floor of the mouth, tongue, and oropharynx. The age group is divided into 10 years. The level of education was divided into illiteracy, primary education level and advanced education level. Body mass index (BMI) was divided into three levels by 18 kg/m² and 25 kg/m². Visual analog scale (VAS) method was to evaluate the patient's preoperative pain. At the same time, the patients were examined by detailed questionnaire to understand the delay factors and delay characteristics, and use SPSS 18.0 software, analysis of variance and chi-square test to explore correlation.

RESULTS

Among all patients, the proportion of patients developed in the tongue was the highest (43.3%). Delay was defined by a span of three months or longer from the onset of symptoms until treatment. The delays to diagnosis according to location were as follows (in months and in descending order): lip (6.1 months), buccal (4.1 months), floor of the mouth (3.9 months), tongue (3.6 months), oropharyngeal (2.9 months), retromolar (2.7 months), palatine (2.4 months), and gingival (2.4 months). Different sites and delayed diagnosis were statistically significant (P=0.048). There were no statistically significant differences in gender, education, pain, smoking, drinking and VAS score.

CONCLUSION

The study has found that tumor positions and delay have a significant correlation. The position of the tumor is an obvious factor associated with the findings. The lip is the most likely to delay the diagnosis of oral positions. For the lip of the lesion, more than three months' obvious mass is recommended for timely treatment, while at admission, physicians should take the appropriate diagnostic method as soon as possible.

[Role and mechanism of muscarinic acetylcholine receptor in the regulation of submandibular gland secretion]

Muscarinic acetylcholine receptors (mAChRs), including M1-M5 subtypes, are classic receptors in regulating water, ion, and solute transport in salivary gland. Our work focuses on the studies on the expression pattern and function of mAChR in the submandibular gland (SMG), and the underlying mechanism involved in the mAChR-regulated secretion, together with the effect of parasympathectomy on the salivary secretion. Microvascular autotransplantation of SMG into the temporal fossa provides a continuous and endogenous source of fluids, and is currently an effective method for treating severe keratoconjunctivitis sicca. By using RT-PCR, Western blotting, and immunofluorescence, our data demonstrated that the expression of M1 and M3 subtypes were decreased in latent period in rabbit SMG autotransplantation model, whereas carbachol stimulation promoted the salivary secretion, as well as M1 and M3 expressions. By contrast, mAChRs were hypersensitive in epiphora SMGs, whereas atropine gel and botulinum toxin A application significantly inhibited the hypersecretion in both animal models and patients. Furthermore, the possible intracellular signal molecules involved in the mAChR-modulated salivary secretion were explored. Activation of mAChR upregulated the expression of aquaporin 5 (AQP5), the main transporter that mediated water secretion through transcellular pathway, and led to AQP5 trafficking from lipid rafts to non-lipid microdomain. Extracellular signal-regulated kinase 1/2 (ERK1/2) was involved in the mAChR-regulated AQP5 content. mAChR activation also modulated the expression, distribution, and function of tight junction proteins, and increased paracellular permeability. ERK1/2/β-arrestin2/clathrin/ubiquitin signaling pathway was responsible for the mAChR-regulated downregulation of tight junction molecule claudin-4. Cytoskeleton filamentous actin (F-actin) was also involved in the distribution and barrier function of epithelial tight junctions. Besides, endothelial tight junctions were opened by mAChR agonist-evoked salivation in the mice. Furthermore, parasympathetic denervation increased resting salivary secretion in the long terminrats and minipigs. Taken together, our work demonstrated that mAChR regulated saliva secretion via transcellular and paracellular pathways in SMG epithelium as well as tight junction opening in SMG endothelium. Modulation of mAChR might be a promising strategy to ameliorate SMG dysfunction.

Cortical bone resorption of fibular bone after maxillary reconstruction with a vascularized fibula free flap: a computed tomography imaging study

This study was performed to evaluate the cortical bone resorption of fibular bone after maxillary reconstruction with a fibula free flap. A total of 35 patients with maxillary defects that were repaired using a fibula flap (62 fibula segments) between January 2011 and January 2016 were enrolled. Computed tomography (CT) images taken 1 week and 1 year postoperative were used to evaluate cortical bone resorption. The 62 fibula segments were measured on four different surfaces in the CT images. At 1 week, the thickness of the cortical bone was 2.57 ± 0.58 mm, 2.72 ± 0.46 mm, 3.84 ± 0.98 mm, and 4.36 ± 0.90 mm for the exterior, interior, superior, and inferior sides, respectively. At approximately 1 year, the cortical bone thickness was significantly reduced to 2.00 ± 0.65 mm (P <  0.01), 2.25 ± 0.60 mm (P <  0.01), 3.37 ± 0.90 mm (P <  0.01), and 2.96 ± 0.84 mm (P <  0.01) for the exterior, interior, superior, and inferior sides, respectively. The cortical bone thickness of fibular bone is significantly reduced 1 year after the restoration of maxillary defects with a fibula free flap, most significantly on the inferior side.

Comparison of the subjective satisfaction of the donor site morbidity: Free radial forearm flap versus anterolateral thigh flap for reconstruction in tongue cancer patients

BACKGROUND

The purpose of the study was to compare the differences of the subjective satisfaction of the donor site morbidity between the free radial forearm flap (FRFF) and anterolateral thigh flap (ALTF) for tongue reconstruction.

MATERIAL AND METHODS

One hundred and nineteen patients underwent FRFF or ALTF reconstruction were retrospectively evaluated by a standardized self-established donor site morbidity questionnaire which included 5 domains, sensibility, movement disabilities, cosmetics, social activities and general impacts on the quality of life.

RESULTS

The Cronbach's coefficient alpha of the questionnaire was 0.707. The exploratory factor analysis revealed that the 5 items of the questionnaire might load onto two distinct subscales. Patients with ALTF had higher scores in the sensibility, cosmetics and the composite score (P < 0.05). No significant differences were found in the movement disabilities, social activities and general impacts on the quality of life between the two groups (P > 0.05).

CONCLUSIONS

ALTF has the advantage of better results of donor site morbidity, such as sensibility and cosmetics, over FRFF.

Non-vascularised fibular bone graft after vascular crisis: compensation for the failure of vascularised fibular free flaps

After reconstruction of a segmental mandibular defect with a fibular free flap, a vascular crisis can be detected clinically and a "no-flow" phenomenon found during re-exploration. Traditional methods used to solve this include removal of the failed flap and delayed mandibular reconstruction, or restoration of the defect with a functional reconstruction plate or contralateral fibular free flap. Our aim therefore was to investigate under what circumstances it is feasible to use a non-vascularised fibular bone graft (NVFB) as a free bone graft after the failure of a vascularised fibular free flap. From 1 January 2010-31 December 2014, 10 patients who had NVFB after failure of a fibular free flap were included in the study. All patients were treated at the Peking University School and Hospital of Stomatology. NVFB were preserved successfully without infection in all 10 cases, and follow-up imaging showed that it had incorporated well with the residual mandible, the basic function and facial aesthetics of which were maintained. In conclusion we have identified that by precise selection of patients, detailed preoperative planning, and meticulous postoperative care, NVFB can be used as a "rescue" technique after failure of a fibular free flap, and can successfully restore the segmental mandibular defect and facial contour.

Botulinum toxin A treatment of epiphora secondary to autologous submandibular gland transplantation

The aim of this study was to explore whether botulinum toxin A (BTXA) injection treats epiphora secondary to submandibular gland (SMG) transplantation for severe keratoconjunctivitis sicca. Fifteen patients with epiphora after SMG transplantation were separated to three groups, and received 15U, 20U and 25U BTXA injection in the transplanted SMG, respectively. Secretion of transplanted SMG was assessed subjectively by visual analogue scale (VAS) regarding epiphora, and objectively by Schirmer test. There were no significant differences in the 15-U BTXA group regarding the values of the VAS on epihora before and 1 month after BTXA injection. While in 20-U group and 25-U group, the values of VAS on epihora decreased significantly after BTXA injection, and lasted for 6months. Under resting conditions, the secretion of transplanted SMG decreased 64.4%, 73.0% and 78.0% in 15-U, 20-U and 25-U groups, respectively (P<0.01), in 1month after BTXA injection; significant secretion decreasing lasted 3months only in the 25-U BTXA group. BTXA injection can decrease the secretion of transplanted SMG significantly, relieving the symptoms of epiphora; 25U BTXA is a suitable dose to treat 'opportunistic epiphora' after SMG transplantation.

[A 20-year study on microvascular autologous transplantation of submandibular gland for treatment of severe dry eye]

Severe dry eye is a refractory ophthalmologic disease. Our multidisciplinary research group treated severe dry eye by microvascular autologous transplantation of submandibular gland (SMG) during the past 20 years. The SMG, with its blood vessels and Wharton's duct, was harvested from the submandibular triangle and transferred to the temporal area. The blood vessels in the SMG were anastomosed with the temporal blood vessels using a microsurgical technique. Then, the distal end of Wharton's duct was sutured to form an opening in the upper lateral conjunctival fold. The tear was replaced by the secretion of the transplanted SMG to lubricate the ocular surface. In our study, the surgical techniques of blood vessel management were continuously modified to increase the survival rate of the transplanted SMG. A novel surgical modality of partial transplantation of SMG was established to prevent postoperative epiphora. A clinical study with the largest case number in the world was conducted and the effectiveness of transplantation of SMG for severe dry eye was fully confirmed. In order to resolve two main clinical problems including ductal obstruction resulted from low secretion rate during the latent period, and epiphora due to over secretion of the transplanted SMG in the later term of transplantation, the regulation of the secretion mechanism of the normal and transplanted SMG were investigated. New opinions on mechanisms of saliva secretion were provided. Based on the priniciple of translational medicine, the results of related basic research were applied in the clinic. The clinical guidelines for secretion regulation of transplanted SMG were established. A concept of chronic obstructive sialadenitis of transplanted SMG was provided and its diagnostic criteria, diagnostic technique of sialography, and therapeutic regimen were established. As a result, the surgical success rate was obviously elevated, the surgical complications were decreased, and life quality of the patients was greatly improved.

Differential diagnosis of IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis

Our aim was to differentiate IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis by analysing clinical, radiographic, and pathological features. Fifty-five patients, 50, and 50 were enrolled, respectively and their baseline characteristics and serological, sialographic, and pathological findings compared. The male:female ratio for IgG4-related sialadenitis was 1:1.2 for primary Sjögren syndrome 1:15.7, and for chronic obstructive submandibular sialadenitis1:0.92. Numbers with enlarged salivary glands were 55, 16, and 50; with xerostomia 26, 48, and 0; with a history of allergy 26, 4, and 6, and with coexisting systemic disease 12, 19, and 0 (p=0.14). Mean (SD) serum IgG4 concentrations were 109.1 (97.9), 4.9. (1.9) g/L, and 5.3 (1.6) g/L, p<0.001 in all cases. Sialography showed enlargement of the gland, dilatation of the duct, and slightly decreased secretory function in IgG4-related disease; obvious sialectasia and decreased secretory function in Sjögren syndrome; and dilatation of Wharton's duct and filling defects in obstructive sialadenitis. Histopathological examination showed lymphoplasmacytic infiltration with storiform fibrosis, lymphoplasmacytic inflammation and lymphoepithelial lesions, and dilatation of the duct with epithelial metaplasia in the three groups, respectively. The number of IgG4-positive plasma cells was 123 (45)/HPF, 8 (3)/HPF, and 5 (4)/HPF, while the IgG4-/IgG-positive cell ratio was 71.7 (13.9)%, 4.6 (2.5)%, 18.9 (19.7)%, respectively (p<0.001). The three conditions have different clinical, radiographic, and pathological features that provide important clues to the differential diagnosis. Serological and histological tests are important, and comprehensive consideration is necessary.

Partial sialoadenectomy for the treatment of benign tumours in the submandibular gland

The conventional treatment for benign tumours arising in the submandibular gland (SMG) has always involved whole gland excision with the tumour. In light of developments in parotid gland functional surgery, this prospective study was performed to evaluate the effectiveness and safety of partial sialoadenectomy (PS) for benign tumours in comparison with conventional total sialoadenectomy (TS). Thirty-one consecutive patients with a preoperative diagnosis of benign tumour in the SMG were included in the study from December 2008 to December 2010. Eleven patients were treated with PS and 20 patients underwent conventional TS. Salivary gland function and surgery-related complications were assessed. No difference in resting saliva flow was found between the two groups before the operation, while this was significantly higher in the PS group than in the TS group at 1 year after surgery (P=0.009). With regard to complications, there was less deformity in facial appearance in the PS group. There was no recurrence in any of the 31 patients during the follow-up period (range 41-82 months). It is believed that this modification to SMG surgery is consistent with the idea of functional and minimal invasive salivary gland surgery. This technique represents a good choice for the management of benign tumours of the SMG for appropriately selected cases.

Pre- and Post-synaptic Effects of Botulinum Toxin A on Submandibular Glands

Intraglandular injection of botulinum toxin type A (BoNT/A) is an effective treatment for sialorrhea. Despite numerous experimental and clinical studies on inhibition of saliva section by BoNT/A, the proteolysis of synaptosomal-associated protein 25 (SNAP-25) following BoNT/A treatment has not yet been confirmed in the salivary gland after injection of BoNT/A. More important, it is not known whether BoNT/A exerts a direct effect in acinar cells. Here, we show that injection of BoNT/A into the rat submandibular gland (SMG) decreased salivary flow in a dose-dependent manner; the inhibitory effect lasted at least 4 wk, and salivary flow recovered to normal levels by 12 wk. During the inhibitory period, SMG neurons and synapses expressed lower levels of full-length SNAP-25, and cleavage of SNAP-25 was observed, as indicated by detection of reduced molecular weight SNAP-25 using Western blotting. In addition, the water channel aquaporin 5 (AQP5) was downregulated and abnormally distributed in rat SMG after injection of BoNT/A. The direct effects of BoNT/A on AQP5 expression and distribution were assessed in vitro to exclude the influence of BoNT/A-induced inhibitory neurotransmission. In stable GFP-AQP5-transfected SMG-C6 cells, treatment with BoNT/A reduced the cell surface protein level of AQP5 in a dose- and time-dependent manner without affecting total AQP5 protein expression. Cell surface biotinylation and immunofluorescence demonstrated translocation of AQP5 from the membrane to the cytoplasm, which was confirmed by decreased levels of AQP5 protein in the membrane fraction and increased levels in the cytoplasmic fraction, suggestive of AQP5 redistribution. Taken together, these results indicated that BoNT/A reversibly decreased saliva secretion in rat SMGs through not only the presynaptic SNAP-25 cleavage but also the postsynaptic AQP5 redistribution. These data provide the first evidence for a direct effect of BoNT/A on the salivary gland.

Multiple primary tumours of the parotid gland

The authors reviewed the clinical and histopathological records of 69 cases of multiple primary tumours (MPT) of the parotid gland treated at Peking University School of Stomatology. It accounted for 3.4% of all parotid tumours (2055 patients). Fifty-nine patients were male and 10 were female. The median age was 58 (range 24-80) years. The average time interval between the diagnosis of bilateral parotid tumours was 5 years (range 5 months-15 years). Three clinical types were classified as bilateral parotid tumours (31 cases), unilateral multifocal parotid tumours (29 cases), and the combination of bilateral parotid tumours with unilateral multifocal parotid tumours (9 cases). Histologically, Warthin's tumour was the most common type (60 patients), followed by pleomorphic adenoma (8 cases). Three cases were malignant including adenoid cystic carcinoma, squamous cell carcinoma and mucoepidermoid carcinoma. The histopathologies of tumours were of the same type in 63 patients, and distinctly different in six patients. The tumours were found and diagnosed synchronously in 48 patients, and metachronously in 21 patients. Since some parotid tumours are MPTs, careful preoperative diagnosis is necessary. B-mode ultrasound is the technique of choice for the screening of MPT. Meticulous intraoperative inspection and palpation of the glandular tissues and periglandular lymph nodes are necessary.

Microvascular autologous submandibular gland transfer in severe cases of keratoconjunctivitis sicca

The objective is to evaluate the technique of microvascular autologous submandibular gland transfer for the treatment of severe keratoconjunctivitis sicca. From August 1999 to April 2002, 38 patients with severe keratoconjunctivitis sicca were treated by autologous submandibular gland transfer to the temporal region of the skull. The related vessels were anastomosed to the superficial temporal artery and vein. When the vein was too small, venous bridging was applied. Prior to cutting off the gland, the facial artery was preserved and infused with heparin in normal saline after the gland had been freed to allow inspection of the blood oozing from the three veins. This would be helpful in the selection of a relevant vein for anastomosis. Wharton's duct was transplanted to the upper lateral conjunctiva fornix, and the gland was left denervated. Postoperative scintigraphy with Tc99m pertechnetate, follow-up studies, and management of complications were performed. The transplantations were successful in 33 cases, their symptoms of xerophthalmia disappeared. The discomfort resulting from bright light and wind was also relieved. These patients could stop applying artificial tears. In five patients the transplanted glands did not survive. Epiphora occurred in eight cases. They were successfully treated by reducing the size of the graft. Obliteration of Wharton's duct took place in two cases and was treated by the reconstruction of the duct or duct orifice. Microvascular autologous submandibular gland transfer is a lasting and effective solution for severe cases of keratoconjunctivitis sicca.

[Investigation on the excited state dynamics properties of hemicyanine molecules]

In this paper, the excited state dynamics properties of hemicynine were investigated by using time-resolved fluorescence and 3D fluorescence spectra techniques. The interaction of hemicyanine molecules caused formation of H-aggregates and a blue shift of the 3D fluorescence spectra in interleaving hemicyanine/arachidic acid multilayers. The peak of fluorescence was a red shift along with the time decay. The lifetime of the LB fluorescence was much shorter and the difference of beginning luminescence was less than that of the hemicyanine solution due to the stronger intermolecule interactions in the aggregates.

Generation of frequency-tunable ultrashort optical pulses with liquid-core fibers

Experimental generation of ultrashort, frequency-tunable optical pulses in liquid-core fibers is reported. Passage of high-energy optical pulses through a submillimeter liquid-core fiber reveals a quasi-linear frequency sweep. The subsequent use of a grating dispersion system and a spectral window shortens the Nd:YAG laser pulse duration from 45 ps to less than 2 ps. Based on spectral filtering after the grating pair, the wavelength of the generated short pulses is shown to be tunable.