Objective Effective tissue perfusion fixation plays an important role in immunofluorescence experiments and other studies .The aim of this study was to modify the method for perfusion fixation of rat brain tissues and improve the efficiency of the procedure . Methods Conventional thoracotomy was modified by cutting the skin from the xiphoid along the mediventral line to the lower jaw to expose both sides of the thorax and then freeing the chest wall .The tip of the infusion needle was cut off and the needle in-serted into the left ventricle , pushed to the ascending aorta , and fixed there to prevent sliding .Perfusion and fixation began after tho-racic aortic occlusion.The regulatory valve was opened , followed by infusion of 0.9%physiological saline and cutting the right atrial appendage .When the perfusate became clear , the infusion tube was replaced , without removal of the needle , and fixed with 4%paraformaldehyde .The fixation process was slowed down gradually till the neck became stiff , which indicated its completion . Results The head, neck and upper limbs were all fixed desirably by this method , which shortened the operation time , saved 4%paraformalde-hyde, and achieved satisfactory immunofluorescence results as compared with conventional procedures . Conclusion The modified method is simple , obviously improves the results of perfusion fixation of rat brain tissue , and therefore deserves to be popularized .

Objective To investigate the effect of zinc oxide oil care on perianal skin ulceration in elderly patients.Methods A total of 90 elderly fecal incontinence patients with perianal skin ulceration were randomized into the observation group(n=48)and the control group(n=42):The former received zinc oxide oil treatment and the latter were treated with mupirocin ointment.Perianal skin injury was evaluated in all the patients and the treatment effect between two groups were statistically analyzed after one week.Result The total effective rate in the observation group(93.8%)was significantly higher than that in the control group(71.4%)(χ2=8.036,P<0.01).Conclusions Management of perianal skin ulceration in bedridden elderly patients with zinc oxide oil may produce better effect.

Objective: To explore influence of long-term oral valsartan-angiotensin II type 1 receptor blocker on ventricular arrhythmia after myocardial infarction (MI) in rabbits and its possible mechanism. Methods: A total of 24 New Zealand rabbits were randomly divided into sham operation group (n=8), MI group (n=8) and valsartan group (n=8) according to number table. Sham operation group only received thoracotomy without ligation of anterior descending branch of left coronary artery (LAD), while MI group and valsartan group received ligation of anterior descending branch of LAD. Valsartan group received valsartan gavage (10 mg•kg-1•d-1) since the second day after operation, three groups all were fed for 12 weeks. Mono active potential (MAP) of left ventricular myocardial cells of subendocardial myocardium（inner layer myocardium）, subepicardial myocardium（outer layer myocardium）and middle layer myocardium were recorded before MI and 12 weeks after MI, and times of provocative malignant arrhythmias were recorded on 12 weeks after MI in three groups. Results: 1. Ventricular tachycardia or fibrillation (VT/ VF) episodes were markedly decreased in VAL group than that in MI group on 12 weeks after MI [(3.1±0.8) vs. (12.7±1.5), P＜0.05]; 2. After MI 12 w, the action potential duration to 90% repolarization (APD90) of three-layer ventricular myocytes in MI group was prolonged than that before MI [（259.2±22.1）ms,（288.0±25.8）ms,（244.6±22.6）ms vs.（230.1±23.2）ms,（244.2±23.4）ms,（229.0±21.7）ms, P＜0.05 or＜0.01]；but there were no significant difference in APD90 of three layers ventricular myocytes between before and after MI in valsartan group (P>0.05 all); Compared with sham operation group and valsartan group, there was significant prolonged in transmural dispersion of repolarization (TDR) [(18.8±6.2) vs. (23.9±7.7) vs. (37.2±10.2), P<0.05 or＜0.01] in MI group; There was no significant difference in TDR between valsartan group and sham operation group (P>0.05). Conclusions: Long-term oral valsartan can significantly reduce malignant ventricular arrhythmia incidence in rabbits after MI, which may be related to improving TDR in rabbits after MI.

Objective To explore the clinical significance of typical reflux symptoms in the diagnosis of gastroesophageal reflux disease (GERD).Methods Consecutive patients older than 16 years,who initially visited department of gastroenterology at clinic of Peking University Third Hospital from May 9,2012 to Dec 31,2012,were required to complete a self-reported GERD questionnaire.Upper endoscopy was performed in some selected patients.Results A total of 18 987 patients were enrolled with a response rate of 91.5％.The prevalence of symptom-defined GERD was 13.6％ (2 579/18 987).A total of 4 357 (22.9％) patients underwent the upper endoscopy,and the diagnostic rates of reflux esophagitis,Barrett's esophagus,peptic ulcer disease,and upper gastrointestinal malignancy were 13.1％ (572/4 357),1.8％ (78/4 357),10.5％ (456/4 357),and 1.7％ (75/4 357),respectively.The incidence of reflux esophagitis was 22.7％ (216/951) in patients with reflux symptoms and 10.5％ (356/3 406) (P ＜0.001) in patients without reflux symptoms,2.7％ (26/951) and 1.5 ％ (52/3 406),respectively (P =0.013) for Barrett's esophagus; 6.8％ (65/951) and 11.5％ (391/3 406),respectively (P＜0.001) for peptic ulcer disease; 1.7％ (16/951) and 1.7％ (59/3 406),respectively (P =0.917) for upper gastrointestinal malignancy.Conclusions GERD is one of the major diseases at gastroenterology clinic.Typical reflux symptoms suggest a diagnosis of GERD.But some patients with peptic ulcer disease or upper gastrointestinal malignancy can also present typical reflux symptoms.Upper endoscopy is valuable to avoid the misdiagnosis of other disorders.

Objective: To investigate the early intervention effects of metoprolol on connexin 43(Cx43) and phosphorylated Cx43 (p-Cx43) expression in rabbits with post myocardial infarction. Methods: A total of 24 adult male New Zealand white rabbits were divided into sham group (n=6), early treatment group(n=6), routine treatment group(n=6), and myocardial infarction group(n=6) with a randomized block design blocked by weight. Myocardial infarction was induced by left anterior descending coronary artery (LAD) ligation. Rabbits in sham group received similar surgical procedure without LAD ligation. Metoprolol (12.5 mg/kg dissolved in 2 ml distilled water) was applied to rabbits in early treatment group and routine treatment group per gavage immediately after recovery from anesthesia and at 24 hours after myocardial infarction, respectively, then treated daily for 40 days. Rabbits in sham group and myocardial infarction group received 2 ml distilled water per gavage daily for 40 days. Plasma lactate dehydrogenase (LDH) and creatine kinase (CK) level were detected by automatic biochemistry analyzer after 6 hours in all rabbits. Ventricular fibrillation threshold (VFT) was measured in vivo by bipolar pacing electrodes at 40 days. Cx43 and p-Cx43 distribution in ventricular tissue was detected by immunofluorescence analyses. Cx43 and p-Cx43 protein level in ventricular tissue was determined by Western blot. Results: (1) Plasma LDH ((851.7±85.9)U/L vs. (332.3±39.6)U/L, P<0.01) and CK ((1 192.7±105.3)U/L vs. (462.3±65.6)U/L, P<0.01) were significantly higher in myocardial infarction group than in sham group (both P<0.01). (2) VFT was significantly lower in myocardial infarction group than that in sham group ((470.0±91.0) beats per minute vs. (683.3±60.9) beats per minute, P<0.05), and VFT was significantly higher in early treatment group ((633.3±43.2) beats per minute) and routine treatment group ((645.0±30.8) beats per minute) than in the myocardial infarction group (both P<0.05). (3) Immunofluorescence analyses showed that Cx43 was mainly localized in the intercalated disk, which was perpendicular to the cell long axis with linear arrangement, and less lateral distribution in sham group, early treatment group and routine treatment group, which was significantly different as the case in the myocardial infarction group. The expression of p-Cx43 in myocardial infarction group was less than in sham group, which was significantly upregulated in in early treatment group and routine treatment group when compared with myocardial infarction group, and expression of p-Cx43 was significantly higher in early treatment group than in routine treatment group. (4)The p-Cx43/Cx43 ratio of protein was significantly lower in myocardial infarction group than in sham group (0.165±0.011 vs. 0.363±0.046, P<0.05), and significantly higher in early treatment group (0.720±0.063) and routine treatment group (0.364±0.030) than in myocardial infarction group (both P<0.05), and this ratio was significantly higher in early treatment group than in routine treatment group (P<0.05). Conclusion Metoprolol treatment, especially the early metoprolol treatment (within 24 hours after LAD ligation), could significantly improve VFT by ameliorating the distribution and dephosphorylation of myocardial Cx43 in rabbits with experimental myocardial infarction.

Objective: To evaluate the clinical efficacy of modified lateral window for maxillary sinus floor augmentation (MSFA). Methods: Fifty-five patients who visited the Stomatology Hospital Affiliated to Zhejiang University School of Medicine between June 2012 and October 2014 were enrolled in the study. Patients underwent MSFA with Bio-Oss grafts based on modified access window. During the operation the vertical height of the bony window was reduced from 6-8 mm of conventional oval window to 4-5 mm of slot-shaped window. The sinus membrane was detached completely via the lateral access and large particle Bio-Oss graft was placed in the sub-mucosal space. The implant survival, graft height, graft volume and resorption rates were measured. Intra-op and post-op complications were recorded. Results: There were 86 implants inserted. The 2-4 year cumulative survival rates were 97.67% by implant-based analysis and 96.36% by patient-based analysis. The residual bone height was (4.7±2.6) mm and bone width was (8.4±2.7) mm. The bone height of implantation site immediately after operation was (16.1±2.5) mm and it was (16.2±2.2) mm at restoration. The bone heights at 1 and 2 years after operation were (14.9±2.5) mm and (13.6±2.6) mm, respectively. The graft height was (10.6±2.8) mm and the graft volume was (1569±745) mm³ immediately after operation. The resorption rate of graft height 6 months after operation was 3.79% and that of graft volume was 7.87%. The 1-year accumulative resorption rate of graft height was 6.63% and that of graft volume was 10.89%. The 2-year accumulative resorption rate of graft height was 7.58% and that of graft volume was 15.26%. Small membrane perforation during MSFA was observed in 5 cases and all were successfully repaired by a collagen Bio-Gide membrane. Conclusion: The modified lateral technique obtains high implant survival rate, excellent graft stability and low complication rate at 2-4 year clinical follow-up, indicating that it is a safe, predictable and minimally invasive surgical method for severe atrophic maxillary posterior dentition.
Dental Implantation, Endosseous ; Follow-Up Studies ; Humans ; Maxillary Sinus ; surgery ; Sinus Floor Augmentation ; methods ; Treatment Outcome

Objective To explore the age-related biological properties of bone-derived mesenchymal stem cells(BMSCs)from mice of different age groups and their osteogenic differentiation induced by bone morphogenetic protein 2(BMP2).Methods Eight C57BL/6J mice were divided into a young group(4 weeks old,weighing 10～15 g,n=4)and an old group(12 months old,weighing 20～25 g,n=4),with half male and half female.MSCs were extracted from the whole bones of the 2 groups of mice.After the obtained cells were identified with flow cytometry for the surface markers,β-galactosidase staining was employed to compare the senescence level of BMSCs,MTT and EdU incorporation assays were conducted to compare the proliferation and self-renewal abilities of between the 2 groups.Western blotting was employed to analyze the expression of CyclinD1 and P21 in BMSCs.Then ALP staining,Alizarin Red staining and RT-qPCR were used to evaluate the osteogenic differentiation ability of the cells.RNA sequencing was performed to compare the differential gene expression in BMP2-induced BMSCs.Lastly,the sequencing results were re-confirmed by using flow cytometry.Results Flow cytometry showed that the sorted and cultured mouse BMSCs met the criteria for MSCs.The results of β-galactosidase staining indicated that the senescence level of BMSCs in the old group was significantly higher than that in the young group(P＜0.05).MTT and EdU doping experiments revealed that the cell viability and proliferation ability of BMSCs were significantly lower in the old group than the young group(P＜0.05).Western blotting displayed that the expression level of cell cycle protein CyclinD1 was lower,whereas that of cell cycle inhibitory factor P21 was significantly higher in the BMSCs from the old group than the cells from the young group(P＜0.05).ALP/Alizarin Red staining and RT-qPCR demonstrated that the BMSCs from the young group had stronger osteogenic differentiation capacity after BMP2 treatment when compared the cells of the old group(P＜0.05).RNA sequencing results displayed that the changing profile of CD51 expression was in opposite trends in the young and old BMSCs after BMP2 treatment.Finally,flow cytometry revealed that the percentage of CD51+cells within the CD45-cells was significantly higher in the young group than the old group.Conclusion The decrease in the percentage of CD51+cells among CD45-cells in aged BMSCs is closely associated with their decreased responsiveness to BMP2-induced osteogenic differentiation.