BACKGROUND:Amount of debris extruded apicaly is an important indicator to evaluate the effect of root canal preparation instrument. Studies have shown that debris extruded apicaly can cause post-treatment pain, and thus, reducing the amount of debris extruded apicaly can decrease the incidence of post-treatment pain. OBJECTIVE:To compare the root canal cleanness and the amount of apicaly extruded debris during root canal preparation with Self-adjusting files, ProTaper Next and ProTaper Universal. METHODS:Forty-five premolars with single canal were divided into three groups randomly, and then prepared by Self-adjusting files, ProTaper Next and ProTaper Universal, respectively. Debris extruded apicaly was colected, dried and weighed. Then roots were longitudinaly sectioned and observed under scanning electronic microscope to evaluate the cleanness of the root canal. RESULTS AND CONCLUSION:The amount of apicaly extruded debris in the ProTaper Universal group was significantly higher than that in the Self-adjusting files group and ProTaper Next group (P < 0.05), but there were no statisticaly significant differences between the groups of Self-adjusting files and ProTaper Next in apicaly extruded debris (P > 0.05). Scores on debris and smear layer were lower in the group of Self-adjusting files than the groups of ProTaper Next and ProTaper Universal (P < 0.05), but there was no difference between the latter two groups (P > 0.05). These findings indicate that the Self-adjusting files and ProTaper Next can extrude less debris beyond the apical foramen, which may decrease the incidence of post-treatment pain. Cleaning ability of Self-adjusting files is better than ProTaper Next and ProTaper Universal.

Objective:To investigate the function of β-arrestin1 and its related mechanisms in migration and invasion capacity of leukemia cell K562. Methods:β-arrestin1-siRNA or negative siRNA was transfected into K562 cells of experiment group or control group. The migration and invasion capacity of K562 cells was detected by transwell tests;and the protein expression of β-arrestin1 and pSTAT3 were detected by Western blot. Results:As compared to control group and negative siRNA group,the migration and invasion capacity of transfected β-arrestin1-siRNA group were attenuated about 43% or 52% ( P<0. 05 );Western blot showed that the expression of phosphorylation of STAT3 was decreased inβ-arrestin1-siRNA group. And the STAT3 inhibitors obviously suppressed the migration and invasion capacity of K562 cells. Conclusion:In leukemia cells K562,β-arrestin1 activates STAT3 signaling pathway to promote the cell migration and invasion.

Objective:To prepare and characterize chitosan/hyaluronic acid (CS/HA) nanoparticles for miRNA-148b (miR-148b)delivery.Methods:CS/HA/miR-148b nanoparticles were prepared.The particle size,zeta potential,morphology were investigated by nano laser granulometer and TEM respectively.The encapsulation efficiency of CS/HA nanoparticles was evaluated by gel retarding analysis.The cytotoxicity and transfection efficiency of CS/HA/miR-148b nanoparticles on rat bone marrow mesenchymal stem cells (MSCs) were evaluated by CCK-8 assay,transfection assay and FCM respectively.Results:The CS/HA/miR-148b nanoparticles were discrete spherical particles with the diameter of 160 to 370 nm and zeta potential of + 15 to +41 mV.N/P ratio at 20∶1 of the nanoparticles showed the optimum encapsulation efficiency for miR-148b.CS/HA/miR-148b nanoparticles exhibited no cytotoxicity to MSCs and could deliver miR-148b to the MSCs at high transfection efficiency.Conclusion:CS/HA/miR-148b nanoparticles are safe and effective for miR-148b delivery into MSCs.

Objective To explore the possible immune pathophysiology of CD4+T regulatory(CD4+Treg)in acquired aplastic anemia(AA).Methods The levels of CD4+CD25+Treg、CD4+CTLA-4+Treg、CD4+PD-1+Treg、CD3+CD8-IL-10+Treg、CD3+CD8-TGF-?1+Treg、CD3+CD8-IL-4+ Treg in the bone marrow of 23 cases of AA at active phase,10 cases of AA at recovery phase and 15 normal controls were measured,and the relationship between CD4+Treg and priming immune factor-CD28 or effective immune factor-IFN-? was also evaluated respectively.Results Contrast to normal controls,while CD4+CTLA-4+Treg of AA at active phase decreased markedly,levels of other CD4+Treg:CD4+CD25+Treg,CD4+PD-1+Treg,CD3+CD8-IL-10+Treg,CD3+CD8-TGF-?1+Treg and CD3+CD8-IL-4+Treg did not change significantly.Contrast to normal controls,the ratio of membrane costimulatory of CD28/CTLA-4 and CD28/PD-1 were all increases significantly in AA at active phase;the ratio of cytokines in cell plasma of IFN-?/IL-4,IFN-?/TGF-?,and IFN-?/IL-10 were also increased significantly.Conclusion In AA,not only at priming stage but also at effective stage,the positive costimulatory increased while the negative regulatory costimulatory decreases or dose not change,which shifted the immune balance to intensification.That the CD4+Treg does not expand to control the intensified immune reaction might be one of immunopathgenesis of AA.

Objective Drug-induced immune thrombocytopenia (DITP) is a major adverse drug effect mediated by drugdependent antibodies.It can be actuated by a wide range of medications,including Rifampicin.Methods Rifampicin-dependent antibody (rd-Ab) from a rifampicin-treated tuberculosis patient with thrombocytopenia (RITP) was characterized by in vitro and in vivo assays,which includes flow cytometry,monoclonal antibody immobilization of platelet antigens (MAIPA) assay,platelet aggregation assay and RITP mouse model.Results The rd-Ab could bind glycoprotein (GP) Ⅱ b/Ⅲ a,as shown by the MAIPA assay.The binding of rd-Ab could be blocked by AP2,a monoclonal antibody that binds a calcium dependent site on GP Ⅱ b/Ⅲ a complex and inhibits ADP-induced platelet aggregation.These results suggested that rd-Ab binds the same site or proximal sites on the GP Ⅱ b/Ⅲ a complex as AP2.Furthermore,the rd-Ab inhibited platelet aggregation in vitro.In an established NOD/SCID mouse model of RITP,the rd-Ab caused a rapid clearance of human platelets (MPL=1.1 ± 0.2h).The in vivo platelet loss could be partially prevented by treatments with intravenous immunoglobulin (IVIG) or corticosteroids (MPL=4.7 ± 0.7h and 4.2 ± 1.1h,P＜0.05).Slowing of platelet clearance was observed immediately upon IVIG treatment,while upon corticosteroid treatment at 24h,and reaching its peak at 72h.Combination of IVIG and corticosteroid treatments was more efficacious (MPL=6.2 ± 1.5h,P＜0.05).Conclusions 1.The rd-Ab binds to calcium-dependent-epitopes on the calcium dependent site of GP Ⅱ b/Ⅲ a complex,which causes platelet damage and inhibits platelet aggregation.2.Either IVIG or corticosteroid alone can partially block platelet clearance by rd-Ab.Slowing of platelet clearance is observed immediately upon IVIG treatment,or upon corticosteroid treatment several days later,indicating that IVIG may be more suitable for acutely raising the platelet count than corticosteroid treatment for RITP.3.Combination of IVIG and corticosteroid treatment is more efficacious than IVIG or corticosteroids alone.

AIM: To investigate the effect of L-phenyla lanine on vascular remodeling in hypertensive rats. METHODS: Vascular remodeling was measured by laser scanning conf ocal microscopy (LSCM) in mesenteric resistance arteries isolated from spontaneo usly hypertensive rat (SHR) and normotensive Wistar-Kyoto (WKY) rat. The effect of L-phenylalanine on the hypertensive vascular remodeling was observed. The thi rd most distal first-order branches of mesenteric resistance arteries from SHR a nd WKY were studied. The arteries were fixed under pressure. The segments were s tained with the nuclear dye propidium iodide. The diameter, wall thickness and o rientation angle of smooth muscle cells were measured with LSCM. RESULTS: Compared with WKY, SHR arteries showed: (1) smaller lum en, (2) increased wall thickness, (3) disorganized orientation angle of smooth m uscle cells. L-phenylalanine treatment induced specific changes in the lumen, wa ll thickness and the orientation angle of smooth muscle cells. CONCLUSIONS: Hypertension induces vascular remodeling of the bra nches of mesenteric arteries from SHR. L-phenylalanine inhibits the vascular rem odeling process of hypertension.

Objective To investigate the feasibility and clinical efficacy of laparoscopic disc hand assisted laparoscopic splenectomy(LDHALS) for patients with ruptured spleen.Methods LDHALS was performed in 14 patients with ruptured spleen,and among them,8 cases were combined with other visceral trauma.Results All cases were performed successfully by using LDHALS.The median operation time was 70 min(45～100 min).The average hospital stay was 7 days in 6 cases with only spleen trauma and 13.5 days in 8 cases combined with other injuries.No major operative complications and mortality occurred.Conclusion The LDHALS is safe,effective,simple and flexible performed for patients with ruptured spleen.

Objective:To investigate the appropriate age for booster doses of hepatitis B vaccine in children aged 0-14.Methods:Retrospective study.A total of 3 118 children aged 0-14 years who underwent quantitative serological marker testing for hepatitis B virus at the Affiliated Hospital of Hangzhou Normal University from January 2015 to October 2021 were recruited in this analysis.There were 1 702 males and 1 416 females, with a male to female ratio of 1.20∶1.00.Children were divided into 15 groups according to their age, and the classifying interval was 1 year.The hepatitis B virus surface antibody (Anti-HBs) titer was quantified by chemiluminescent microparticle immunoassay.The Anti-HBs positivity rates and hepatitis B immune response among groups of different sexes and age were compared by the chi- square test and rank- sum test, respectively. Results:A total of 3 118 children were investigated.The titer and effective response rate of Anti-HBs decreased gradually with age.The difference in the titer and effective response rate of Anti-HBs was statistically significant among groups of different age (all P<0.01), but not significant between males and females (all P>0.05). The median titer of Anti-HBs in children aged above 3 years was 58.49 IU/L(0-1 001.00 IU/L). About 59.1% (1 477/2 497 cases) of children aged 3 years and above had no immune response or low immune response (i.e., the titer of Anti-HBs was below 100 IU/L). Conclusions:The immune protective effect of the hepatitis B vaccine decreases year by year in children who have received the standardized vaccine, and the vaccine has poor protective effect on most children aged 3 years and above.Therefore, booster dose vaccination for preventing hepatitis B is necessary for children aged 3 and above.

Objective To develop a predictive model for pulmonary embolism(PE)based on the related clinical symptoms,signs,and the labo-ratory index,so as to improve the positive rate of CTPA. Methods The model was developed from a database of 119 patients with suspected PE. The risk factors of suspected PE were analyzed by logistic regression analysis ,which included significant differences in the prevalence of PE be-tween non-diseased and non-diseased groups. Receiver operating characteristic(ROC)curves was draw to determine the cut-off value of the clini-cal probability. It was validated in an independent sample of 106 patients with suspected PE. Results According to the univariate analysis ,17 of 51 variables show a significant difference between PE and non-PE patients. The model comprised 4 variables:age,dyspnea,D-dimer and unilater-al leg swelling. The area under the ROC curve is 0.776,and the cut-off value is supposed to be 0.38. In the validation sample,27% patients had PE confirmed by CTPA. The prevalence of PE was 54%when the clinical probability was above 0.38. Conclusion The proposed predictive mod-el in this study can improve the positive rate of CTPA ,simplify the diagnosis process of suspected PE patients.

Objective To evaluate the contraception efficacy, mode of bleeding, side effects and other positive effects of drospirenone-ethinylestradiol (Yasmin) in healthy Chinese women. Methods This was a multicenter, randomized, control study of 768 healthy Chinese women who consulted about contraception. The subjects were randomized into Yasmin group (30 μg ethinylestradiol plus 3 mg drospirenone, 573 cases) or desogestrel group (30 μg ethinylestradiol plus 150 μg desogestrel, 195 cases) with the ratio of 3: 1. Each individual was treated for 13 cycles. Further visits were required at cycle 4, cycle 7, cycle 10 and cycle 13 of treatment. Weight, height, body mass index were evaluated at each visit. The menstrual distress questionnaire (MDQ) was given to the women at baseline, visit 3 (cycle 7) and visit 5 (after cycle 13). Results The values of basal features were similar between two groups (P> 0.05). The Pearl index (method failure) of Yasmin was 0. 208/hundred women year which was lower than that of desogestrel (0. 601/hundred women year). The mode of bleeding was similar between two groups after trial without showing any significant difference. According to MDQ subscale, the improvement of water retention and increasing appetite during inter-menstrual period and water retention and general well-being during menstrual period in the Yasmin group ( -0. 297, -0. 057, 0. 033, 0. 150 respectively) was more obvious than that in the desogestrel group ( - 0. 108, 0. 023, 0. 231, - 0. 023 respectively) with a significant difference (P < 0. 05 ). Some other values which improved in beth two groups, especially the improvement of breast tenderness and pain and skin abnormality in Yasmin group (18.0%, 89/494; 12. 6%, 62/494) was more distinct than that in desogestrel group (11.3%, 19/168; 5.4%, 9/168). The mean weight increased in desogestrel group (0. 57 kg) while it decreased in Yasmin group ( -0. 28 kg) with a significant difference (P < 0. 01 ). Conclusions Both Yasmin and desogestrel have good efficacy on contraception and similar modes of menstrual bleeding. Yasmin is better than desogestrel in terms of weight control and premenstrual syndrome of oral contraceptive.