Recent progress in the treatment of intractable sialolithiasis / 北京大学学报(医学版)

Sialolithiasis occurs in approximately 0.45% to 1.20% of the general population. The typical clinical symptom manifests as a painful swelling of the affected glands after a meal or upon salivary stimulation, which extremely affects the life quality of the patients. With the development of sialendoscopy and lithotripsy, most sialoliths can be successfully removed with preservation of the gland. However, sialoliths in the deep hilar-parenchymal submandibular ducts and impacted parotid stones located in the proximal ducts continue to pose great challenges. Our research center for salivary gland diseases (in Peking University School and Hospital of Stomatology) has used sialendoscopy for 17 years and treated >2 000 patients with salivary gland calculi. The success rate was approximately 92% for submandibular gland calculi and 95% for parotid calculi. A variety of minimally invasive surgical techniques have been applied and developed, which add substantial improvements in the treatment of refractory sialolithiasis. Further, the radiographic positioning criteria and treatment strategy are proposed for these intractable stones. Most of the hilar-parenchymal submandibular stones are successfully removed by a transoral approach, including transoral duct slitting and intraductal basket grasping, while a small portion of superficial stones can be removed by a mini-incision in submandibular area. Impacted stones located in the distal third of parotid gland ducts are removed via "peri-ostium incision", which is applied to avoid a cicatricial stenosis from a direct ostium incision. Impacted parotid stones located in the middle and proximal third of the Stensen's duct are removed via a direct mini-incision or a peri-auricular flap. A direct transcutaneous mini-incision is commonly performed under local anesthesia with an imperceptible scar, and is indicated for most of impacted stones located in the middle third, hilum and intraglandular ducts. By contrast, a peri-auricular flap is performed under general anesthesia with relatively larger operational injury of the gland parenchyma, and should be best reserved for deeper intraglandular stones. Laser lithotripsy has been applied in the treatment of sialolithiasis in the past decade, and holmium ∶YAG laser is reported to have the best therapeutic effects. During the past 3 years, our research group has performed laser lithotripsy for a few cases with intractable salivary stones. From our experiences, withdrawal of the endoscopic tip 0.5-1.0 cm away from the extremity of the laser fiber, consistent saline irrigation, and careful monitoring of gland swelling are of vital importance for avoidance of injuries of the ductal wall and the vulnerable endoscope lens during lithotripsy. Larger calculi require multiple treatment procedures. The risk of ductal stenosis can be alleviated by endoscopic dilation. In summary, appropriate use of various endoscopy-assisted lithotomy helps preserve the gland function in most of the patients with refractory sialolithiasis. Further studies are needed in the following aspects: Transcervical removal of intraglandular submandibular stones, intraductal laser lithotripsy of impacted parotid stones and deep submandibular stones, evaluation of long-term postoperative function of the affected gland, et al.

Inflammation grading and sialoendoscopic treatment of 131I radioiodine-induced sialadenitis / 北京大学学报(医学版)

OBJECTIVE@#To investigate the inflammation grading of 131I radioiodine-induced sialadenitis based upon sialoendoscopic and sialographic appearances, and to evaluate the results of sialoendoscopic intervention.@*METHODS@#The patients diagnosed with 131I radioiodine-induced sialadenitis and underwent sialoendoscopic exploration and intervention procedures in Peking University Hospital of Stomatology from Nov. 2012 to Oct. 2018 were included in this study. The appearances of sialogaphy and sialoendoscopy were analyzed and classified. The treatment options included irrigation with saline and dexamethasone and mechanical dilatation by sialoendoscope. The patients were followed up after treatment.@*RESULTS@#Forty-two patients with 131I radioiodine-induced sialadenitis were included. There were 5 males and 37 females, with a male-to-female ratio of 1 ∶7.4. Symptoms included recurrent swelling and pain in the parotid glands, and dry mouth. Sialography showed stenosis in the main duct,and in some cases nonvisua-lization of the branches. Sialoendoscopy showed narrowing of the main duct, and the branch duct atresia was seen. The appearances of sialogaphy and sialoendoscopy were analyzed and classified into 3 groups: (1) Mild inflammation: stenosis and ectasia occurred in the main duct, whereas the 0.9 mm sialoendoscope could pass through easily. (2) Moderate inflammation: one point of severe stricture could be seen in the main duct where 0.9 mm sialoendoscope could not be passed through. (3) Severe inflammation: two points or more of severe strictures or diffused strictures occurred in the main duct. Thirty-three patients with 65 affected glands were examined by both sialography and sialoendoscopy. Eight glands were classified as mild inflammation, 23 glands moderate inflammation, and 34 glands severe inflammation. The duration of follow-up ranged from 3-72 months. The clinical results were evaluated as good in 22 glands, fair in 22 glands, and poor in 19 glands, with an overall effective rate of 69.8% (44/63).@*CONCLUSION@#The clinical, sialographic and sialoendoscopic appearances of 131I radioiodine-induced sialadenitis showed their characteristics. We proposed an inflammation grading standard for the 131I radioiodine-induced sialadenitis based on the appearances of sialography and sialoendoscopy. Sialoendoscopy can significantly alleviate the clinical symptoms, which is an effective therapy, and better for early lesions.

Endoscopy-assisted sialodochoplasty for the treatment of severe sialoduct stenosis / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the effects of endoscopy-assisted sialodochoplasty for the treatment of severe sialoduct stenosis with concurrent megaducts.@*METHODS@#From Jul.2010 to Dec. 2016, 8 patients presenting with severe parotid duct stenosis and 3 patients with occlusion of the Wharton's duct underwent endoscopy-assisted sialodochoplasty.All these patients had concurrent severe ductal ectasiaand manifested a painful swelling of the involved salivary glands.The diameter of ectasia and length of stenosis of the sialoducts were measured preoperatively by sialography, computed tomography, or ultrasonography. The megaducts were opened transorally and sutured to the buccal or oral floor mucosa, therefore creating a neo-ostium. All the patients were followed up periodically after operation. The treatment effects were evaluated by clinical signs, sialogram and sialometry.@*RESULTS@#The length of the Stensen's duct stenosis was 5-12 mm, and the diameter of the concurrent ectasia was 8-16 mm. The length of the Wharton's duct stenosis was 10-20 mm, and the diameter of the concurrent ectasia was 6-8 mm.The neo-ostiums healed uneventfully 2 weeks after operation. The duration of the follow-up varied from 6 to 78 months (median: 24 months). Among the 8 patients with Stensen's duct stenosis, two experienced re-obliteration of the neo-ostium, but the buccal bulge and clinical symptoms disappeared; one reported recurrent clinical symptoms after initial alleviation, which could be controlled with self-massaging; the remaining 5 patients had satisfactory clinical results, i.e., disappearance of the obstruction symptoms and buccal bulge, patent ostium,clean saliva and improvement of the ductal ectasia on sialogram. Three patients with Wharton's duct occlusion were asymptomatic with clear saliva and patent ostium;two exhibited approximately normal appearance and one showed improvement of the sialogram.Sialometry was performed in 9 patients with patent neo-ostium of the involved glands,the resting saliva flow rate of the affected glands showed no differences compared with the normal side, and stimulated flow rate showed a significant increase, though less than the control side.The clinical results included good in 5 patients, fair in 4 patients, and poor in 2 patients, with a total effective rate of 82% (9/11).@*CONCLUSION@#Endoscopy-assisted sialodochoplasty appears to be effective and can be a viable option for patients presenting with severe sialoducts tenosis and concurrent ectasia.

Optimization of isolation and culture of LinSca-1cardiac stem cells from newborn mice / 生理学报

Cardiac stem cells (CSCs) transplantation has been recognized to be effective on the treatment of myocardial infarction (MI), but some techniques still need to be developed in the isolation and culture of CSCs, which is the key problem restricting the clinical application of CSCs. This study was focused on the isolation of Lin(lineage-negative) Sca-1(stem cell antigen-1-positive) CSCs from newborn C57BL/6J mice (0-3 d) by mixed enzymatic-explant isolation in combination with immunomagnetic separation. The digesting time, digesting frequency, incubation temperature, stirring speed, centrifugation time and rotational speed were strictly controlled in the experiment. In order to increase the survival rate of CSCs, the medium changing time and manner were optimized in primary CSCs culture. The percentages of Sca-1cells in primary and passage cells were detected by flow cytometry and immunofluorescence staining. The results showed that: (1) the proportion of LinSca-1cells within the collected cells could be as high as (85.03 ± 5.60)% after isolation and purification; (2) In vitro culture of LinSca-1CSCs grew into spheres on the 5day, and over the whole bottom of the dish on the 7day. The growth curve showed that the cells were in logarithmic growth phase on the 3day; (3) Immunofluorescence staining data showed that the expression of Sca-1, the CSCs membrane-specific marker, was decreased after subculture, and flow cytometry data showed that the percentages of Sca-1cells were (71.82 ± 2.63)%, (58.38 ± 3.70)% and (46.19 ± 4.72)% in passage 1 (P1), P3, and P5 CSCs, respectively. The above results suggest that high purity of LinSca-1CSCs can be obtained by enzymolysis combined with immunomagnetic separation method. Moreover, the CSCs culture system is stable. In our experiment, the Sca-1CSCs isolation and culture method has been successfully established, and it is simple, stable, effective and reliable. The method can provide a stable methodological basis for the treatment of MI by LinSca-1CSCs transplantation.

Evaluation of OCT on retinopathy induced by tunicamycin in rats / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To evaluate the morphological and functional changes of retinas induced by treatment of tunicamycin with optical coherence tomography (OCT) in rats.METHODS:Totally 60 SD rats were randomly divided into 3 groups (20 in each group), 0.5mg/kg (in low dose group), 1.5mg/kg (in high dose group) tunicamycin were injected into vitreous cavity and saline (9g/L NaCl) were injected in the same dose as a control group.Changes of retinas were observed by OCT on the 1,7 and 14d after treatment of tunicamycin.Then the rats were sacrificed, retinas were taken out and embedded by the paraffin, tissue sections and the HE staining were performed.RESULTS:OCT results suggested that tunicamycin played damage effects on retinal morphology and structure which appeared a time-and dose-dependent.Fundus photography results suggested that 2wk after tunicamycin treatments, with the gradually changing of tunicamycin concentration, peripheral retinal and macular region became pale color gradually, edema occurred in optic disk, retinal vessels appeared thinner in the high dose group, optic nerve came out atrophy.Fluorescein angiography confirmed that tunicamycin injection in vitreous cavity 2wk later, retinal vessels injury occurred, resulted in leaking of intravascular contrast agent from peripheral to the central part of the retinas.Electrophysiological data showed that retinal electrogram occurred disorder induced by tunicamycin, such as the amplitude of a wave, b wave decreased gradually, even closed to zero, which was very different from control significantly (P<0.05).HE staining of paraffin sections showed that retina injuries induced by tunicamycin were in dose-time dependent, which was consistent with the results of OCT.CONCLUSION: Clinical retinal diseases could be simulated by retinal damage animal model induced by tunicamycin treatment.OCT detection offered real-time images of the retinal cross-section, which provided a helpful non-invasive method for detecting and evaluating the retinal damages.

Teaching Discussion on Experimental Pathogenic Bacteria-detection Training for Food Quality and Safety Undergraduate Students / 微生物学通报

Teaching principles and class content were stated for a experimental course of common pathogenic bacteria detection methods for the undergraduate student in food quality and safety major. They include course material preview, advanced teaching methods, combination of teaching and research, graduate teaching assistant, experimental reports writing and experimental skills evaluation. All these means lead to a good teaching outcome.