BACKGROUND:The elastic modulus of the fiber post is close to that of the dentine, so they can form a homogeneous whole and share the masticatory force, which can ease the stress concentration of dentine and prevent from tooth fracture. OBJECTIVE:To observe clinical effects of anterior teeth with flared root canals restored by fiber posts using three application methods. METHODS:Anterior teeth with flared root canals from 48 patients were involved. They were divided into three groups, then restored with three post-core crowns respectively: a single fiber post, rehabilitation with composite resin, and fiber post combined with accessory post. Al patients were folowed up for 2 years to observe post and core loosening, fracture and root fracture. RESULTS AND CONCLUSION:The group of a single fiber post was failed in eight teeth including four cases of post and core loosening and four cases of post and core fracture, with a successful rate of 64%. The group of rehabilitation with composite resin was failed in three teeth including two cases of post and core loosening and one case of post and core fracture, with a successful rate of 90%. The group of fiber post combined with accessory post was failed in two teeth of post and core loosening, with a successful rate of 93%. The successful rate of the group of a single fiber post was lower than that of the groups of rehabilitation with composite resin and fiber post combined with accessory post (P < 0.05) . The difference between the groups of rehabilitation with composite resin and fiber post combined with accessory post was not statisticaly significant (P > 0.05). The clinical effects of rehabilitation with composite resin and fiber post combined with accessory post are better than that of a single fiber post. But the method of combination fiber post with accessory post is recommended because of easy operation.

BACKGROUND:The elastic modulus of the fiber post is close to that of the dentine, so it can form a homogeneous whole and share the masticatory force, which can ease the stress concentration of dentine and prevent from tooth fracture. ＜br> OBJECTIVE:To investigate the effect of alveolar bone height and fiber post length on the fracture resistance of endodontical y treated maxil ary central incisors. ＜br> METHODS:Forty-eight human maxil ary central incisors were assigned randomly to six groups (n=8) of three different post insertion depths (5, 7, 9 mm) and two alveolar bone levels (2 and 5 mm) from the cement-enamel junction. Al of them were restored by glass fiber posts with composite resin core and cast metal crown. The samples were loaded in a testing machine with a crosshead speed of 1 mm/min at a 45° angle to the long axis of the tooth on the palatal surfaces until tooth fracture occurred. The maximum load and failure mode were recorded. ＜br> RESULTS AND CONCLUSION:Alveolar bone height had a significant influence on the fracture resistance (F=560.943, P>0.05), but fiber post length did not have a significant influence on it (P>0.05). Significant differences were found between the normal and resorbed alveolar bone groups in the number of repairable fracture patterns (χ2=5.689, P＜0.05). Under the circumstance of lowered alveolar bone height, lengthening fiber post cannot enhance fracture resistance of the teeth.

Objective To explore the effect and potential mechanism of suppressors of cytokine signaling 3 (SOCS3) knockout on cell viability and apoptosis of retinal ganglion cells (RGCs) after optic nerve injury.Methods The optic nerve transection was used to construct optic nerve injury model of rats,and RGCs were isolated after optic nerve injury.The experimental animals were divided into optic nerve transection injury (ONT) group and sham-operation (Sham) group.The expression of SOCS3 in RGCs was detected by Western blot and RT-PCR in each group.Subsequently,SOCS3 siRNA was transfected into RGCs of Sham group and ONT group,and the experimental were further subdivided into blank control group,negative control group and SOCS3 silence groups.Cell viability was measured by CCK8 and MTr methods.Apoptosis was detected by Hoechst 33342 staining and flow cytometry.Furthermore,the mTOR siRNA and SOCS3 siRNA were co-transfected into RGCs,and cell viability and apoptosis were detected.Results The expression of SOCS3 was dramatically increased at 3 days after injury in the ONT group when compared with Sham group (P =0.049),and it showed an increased tendency gradually along with the extension of injury time.Compared with the blank control in the ONT group,SOCS3 silence markedly promoted cell viability [(49.47 ± 7.35) ％ vs.(73.24 ± 8.70) ％],reduced cell growth inhibition [(27.25 ±0.75)％ vs.(10.96 ± 1.07)％] and apoptosis [(23.06 ± 1.43)％ vs.(10.65 ± 1.77)％].The result of Hoechst 33342 staining indicated that SOCS3 silence ameliorated the cell apoptosis induced by ONT.In addition,SOCS3 silence significantly improved pS6 expression at 2 weeks after injury,and mTOR and SOCS3 co-silence reduced cell viability,increased cell growth inhibition and apoptosis compared with SOCS3 silence group after injury.Conclusion SOCS3 silence promotes injury-induced cell viability of RGCs and suppresses injury-induced apoptosis of RGCs via up-regulating mTOR activity in the later period of injury.

Objective To discuss the effects of applying electric heating pattern instrument in experimental teaching of fixed partial denture technology.Methods Totally 98 prosthodontic undergraduates of 2008 and 2009 grades were selected in this study； 46 students of 2008 grade were taken as control group and 52 students of 2009 grade were taken as experimental group.Students in experimental group made wax patterns with electric heating pattern instruments to melt inlay wax while those in control group made wax patterns with instruments heated by alcohol lamps.Teaching effects were evaluated by experimental test scores and questionnaires.Results Test scores of experimental group were (22.6± 1.8),obviously higher than those of (22.6-± 1.8) in control group (P ＜ 0.05).Satisfaction degree of experimental group were increased significantly compared with that of control group based on the resuits of questionnaire.Conclusions Applying electric heating pattern instrument in making wax patterns in experimental teaching of fixed partial denture technology is easy to operate and can improve the quality of wax pattern and working efficiency as well as enhance students' confidence,therefore it is worthy further spreading.

Objective To investigate the role of Ca2+/calmodulin-dependent protein kinase Ⅱ on pain behavior in a mouse model of bone cancer pain. Methods 40 male C3H/HeN mice were divided randomly into 5 groups:sham group (S group, n=8) ,control group (C group, n=8) and KN93 treat group (T1, n=8;T2, n=8;T3, n = 8 ). Group C and T were induced mouse models of bone cancer pain by intra-left-femur inoculations of osteolytic NCTC2472 cells while group S were injected only α-MEM. On the 14 d after inoculations,group S and C received intrathecal injection of 20% DMSO 5 μl . While group T1, T2, T3 received intrathecal injection of KN93 15nmol,30nmol,60nmol which dissolved in 5 μl 20% DMSO respectively. Mice received pain behavior tests including quantification of spontaneous flinches, paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) before and at 0.5 h,2 h,4 h,8 h after administration. Results Treatment with KN93(15 nmol) have no effect on bone cancer pain,while treatment with KN93(30 nmol,60 nmol) can dose-dependently reverse quantification of spontaneous flinches, mechanical allodynia and thermal hyperalgesia which were induced by bone cancer pain, At 0. 5h after administration, the quantification of spontaneous flinches of the two groups ( (7.25 + 1.49 ), (4. 12 + 1.36 ) ) were decreased when compared with control group ( 11.62 + 1.92 ),PWMT((1.28 +0.14)g;(1.75 +0.46)g),PWTL((14.64 +2.12) s; (16.85 + 1.61)s)were increased when compared with control group ( (0.47 + 0. 16) g, ( 11.32 + 1.68 ) s) (P ＜ 0.05 ＝. The effect lasts for at least 4 h and disappears at 8 h. Conclusion CaMK Ⅱ may play an important role in the mechanism of bone cancer pain. Intrathecal KN93 injection can effectively attenuated bone cancer pain.

BACKGROUND:Recent years, fiber posts and resin cores have been widely used in repairing the endodonticaly treated teeth with satisfactory effect. Erbium:yttrium aluminum garnet (Er:YAG) laser is a new type of water power laser system, which can be used for surface treatment of fiber posts. But studies on the effect of Er:YAG laser surface treatment on the bond strength of fiber posts are rarely reported. OBJECTIVE: To evaluate the effect of surface treatment utilizing Er:YAG laser irradiation with different parameters on the bond strength of fiber posts to root canal dentin. METHODS: Fifty human maxilary central incisors that had similar dimensions were used. After endodontic treatment, removal of the crown and canal preparation, ParaPost FIBER LUX glass fiber posts were cemented into the root canals. According to the method of surface treatment, 50 teeth were randomly divided into: no surface treatment as control group; four groups undergoing surface preparation with Er:YAG laser with four different power settings (150, 250, 350 and 450 mJ at 10 Hz for 60 s at 100-μs pulse duration), named 1.5, 2.5, 3.5, and 4.5 W Er:YAG laser irradiation groups, respectively. RESULTS AND CONCLUSION: The mean bond strength values reduced from the cervical to the apical root canal, and the bond strength of the dental cervix was significantly different from that of middle and apical thirds (P < 0.05), but there was no difference between the middle and apical thirds (P> 0.05). Regardless of the different part of the root slices, the bond strength was highest in the 4.5 W Er:YAG laser irradiation group, showing significant difference from other groups (P < 0.05). These findings indicate that 4.5 W Er:YAG laser irradiation significantly increases the bond strength of the fiber posts to root canal dentin.

Objective To investigate the clinical value of preoperative nutritional support (PNS) therapy in the hepatectomy of patients with nutritional risk.Methods The prospective study was conducted.The clinical data of 133 patients with nutritional risk who were admitted to the Drum Tower Hospital Affiliated to Nanjing University Medical School from August 2012 to June 2016 were collected.All the patients undergoing PNS and traditional therapy were divided into the PNS group and the control group by random number table method,respectively.Observation indicators:(1) comparisons of laboratory indexes between groups;(2) comparisons of postoperative situations between groups;(3) comparisons of postoperative complications between groups.Measurement data with normal distribution were represented as-x±s.Comparisons between groups were evaluated with the independent-sample t test.Comparisons of count data were analyzed using the chi-square test,and repeated measures data were analyzed by the repeated measures ANOVA.Results All the 133 patients were screened for eligibility,including 68 in the PNS group and 65 in the control group.(1) Comparisons of laboratory indexes between groups:alanine transaminase (ALT),aspartate transaminase (AST),total bilirubin (TBil),cholinesterase,albumin (Alb),prealbumin,transferrin and C-reactive protein (CRP) in the PNS group were respectively (36± 13) U/L,(29± 10) U/L,(18.5±2.4) mmol/L,(5 738± 1 824) U/L,(37.4±5.1) g/L,(155±48) mg/L,(2.2±0.5)g/L,(10±4) g/L at admission and (33 ± 9) U/L,(27 ± 8) U/L,(17.9± 1.8) mmol/L,(5 796± 2 016) U/L,(38.5 ± 4.7) g/L,(181 ± 40) mg/L,(2.4± 0.5) g/L,(8± 4) g/L before operation and (285±100)U/L,(218±93)U/L,(33.5±6.3)mmol/L,(4 847±1 044)U/L,(32.6±3.8)g/L,(105±34)mg/L,(1.3±0.4) g/L,(55±28) g/L at 1 day postoperatively and (149±84) U/L,(76±42) U/L,(22.7±4.9) mmol/L,(3 866±893) U/L,(34.2±2.4) g/L,(125±30) mg/L,(1.6±0.4) g/L,(51±34) g/L at 3 days postoperatively and (64±33) U/L,(44±18) U/L,(19.4±2.8) mmol/L,(4 257± 1 032) U/L,(37.0±2.1) g/L,(148±42) mg/L,(1.9±0.4)g/L,(16±11)g/L at 7 days postoperatively;ALT,AST,TBil,cholinesterase,Alb,prealbumin,transferrin and CRP in the control group were respectively (36± 15)U/L,(31± 12)U/L,(18.3±2.9)mmol/L,(5 762±1 693)U/L,(37.3±6.1)g/L,(162±51)mg/L,(2.3±0.5)g/L,(10±4)g/L at admission and (36±11)U/L,(30±11)U/L,(18.2±2.8)mmol/L,(5 789±1 673)U/L,(37.8±7.1)g/L,(166±57) mg/L,(2.3±0.6) g/L,(9±5) g/L before operation and (305±127) U/L,(246± 104) U/L,(34.2±7.8) mmol/L,(4 842±1 173)U/L,(32.0±4.1) g/L,(83±32) mg/L,(1.2±0.4) g/L,(61 ±31) g/L at 1 day postoperatively and (163±104)U/L,(82±62)U/L,(23.1±6.0)mmol/L,(3 672±937) U/L,(33.8±3.6) g/L,(106±30)mg/L,(1.4±0.4)g/L,(61±40)g/L at 3 days postoperatively and (77±48) U/L,(52±27) U/L,(20.2±3.5) mmol/L,(3 925±987) U/L,(36.6±2.8) g/L,(125±40) mg/L,(1.7±0.4) g/L,(22± 12) g/L at 7 days postoperatively,showing no statistically significant difference in changing trends of above indicators between groups (F =1.007,2.223,0.579,0.014,0.235,3.533,2.970,2.143,P＞0.05).Results of further analysis showed that there were statistically significant differences in the levels of ALT,AST and cholinesterase at 7 days postoperatively between groups (t=1.832,2.073,1.899,P＜0.05),and in the levels of prealbumin before operation and at 1,3 and 7 days postoperatively between groups (t =1.698,3.738,3.625,3.178,P＜0.05) and in the levels of transferrin and CRP at 3 and 7 days postoperatively between groups (t=2.917,2.709,1.667,2.990,P＜0.05).(2) Comparisons of postoperative situations between groups:time to initial exsufflation,time of initial defecation,infused volume of exogenous albumin and duration of postoperative hospital stay were respectively (46± 15)hours,(64±16)hours,(23±10)g,(9.2±2.6)days in the PNS group and (55±18)hours,(78±21)hours,(39±25)g,(11.7±5.3) days,with statistically significant differences in the above indicators between groups (t =2.830,4.157,5.044,3.497,P＜0.05).(3) Comparisons of postoperative complications between groups:23 and 33 patients in the PNS and control groups had postoperative complications,showing a statistically significant difference between groups (x2=3.915,P＜0.05).Eight and 17 patients in the PNS and control groups were respectively complicated with peritoneal effusion,with a statistically significant difference between groups (x2 =4.508,P＜ 0.05).Conclusion PNS therapy in the hepatectomy of patients with nutrition risk can effectively improve pre-and post-operative nutrition statuses,reduce liver damage,accelerate recoveries of liver and gastrointestinal functions,reduce complications,shorten duration of postoperative hospital stay and accelerate patients' recovery.

Objective:To investigate the effects of genomic location of a foreign gene in Shanghai-191 strain measles virus (MV) vector on gene expression and virus replication.Methods:The nucleotide sequence encoding S1 protein of SARS-CoV-2 was inserted at different positions in MV antigenome (the upstream of the N gene, between P and M genes, between H and L genes), and co-transfected into 293T cells with helper plasmids coding T7 RNA polymerase and N, P, and L proteins, respectively. The transfected cells were lysed and the supernatants were used to infected Vero cells to harvest recombinant viruses. S1 proteins expressed by the recombinant viruses were identified by RT-PCR, indirect immunofluorescence assay, Western blot and ELISA. Growth kinetics of the recombinant viruses were analyzed.Results:Recombinant viruses were failed to be rescued when the S1 protein-coding sequence was cloned into the upstream of N gene. Two recombinant viruses, MV-M-S1 and MV-L-S1, were successfully rescued when cloning the S1 protein-coding sequence into the intergenic region between P and M genes, or H and L genes, and could express S1 protein. MV-M-S1 expressed more S1 protein than MV-L-S1, but the titer of MV-M-S1 was lower.Conclusions:Inserting a foreign gene at different positions in the MV genome might have different effects on gene expression and virus replication. This study provided reference for the subsequent construction of MV vector.

Objective:To construct a recombinant herpes simplex virus 2 (HSV-2) expressing enhanced green fluorescent protein (EGFP) using clustered, regularly interspaced, short palindromic repeat/CRISPR-associated nuclease 9 (CRISPR/Cas9) technology.Methods:Four strategies for inserting exogenous EGFP gene into HSV-2 genome using CRISPR/Cas9 technology were designed: (1) conventional homology-directed repair: circular two homology arm donor-mediated gene knock-in; (2) linearized single homology arm donor-mediated gene knock-in; (3) homology-independent targeted integration; (4) conventional homology-directed repair-mediated by cell lines stably expressing Cas9 and sgRNA.Results:The recombinant virus HSV-2-EGFP was successfully constructed based on the second, the third and the fourth strategies. The second strategy was the most efficient, followed by the third and the fourth strategies. The purified recombinant virus could stably express green fluorescent protein in seven passages and shared similar growth characteristics in Vero cells to the parental virus.Conclusions:Linearized single homology arm donor could increase the efficiency of gene knock-in, and cell lines stably expressing Cas9 and sgRNA could increase the efficiency of gene knock-in mediated by homology-directed repair.

Objective:To investigate the expressions of CD200 and inducible costimulator (ICOS) protein in angioimmunoblastic T-cell lymphoma (AITL) and the relationship with prognosis as well as their significances in the differential diagnosis of AITL.Methods:A total of 39 AITL patients in the First People's Hospital of Chenzhou, the Fourth People's Hospital of Chenzhou, Xiangnan College Affiliated Hospital and Chenzhou 3rd People's Hospital from June 2012 to December 2019, and 10 patients with classic Hodgkin lymphoma (CHL) and 10 patients with peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) from August 2016 to July 2019 in the First People's Hospital of Chenzhou were selected. Immunohistochemistry was used to detect the expressions of CD200, ICOS, CD10, programmed death 1 (PD-1), bcl-6 and CXC chemokine receptor-13 (CXCL13) proteins, and the correlation of CD200 and ICOS with clinicopathological features and prognosis of AITL patients was analyzed, and the diagnostic significance of both in differentiating AITL from PTCL-NOS and CHL was also analyzed.Results:The positive rates of CD200 and ICOS in 39 AITL patients were 71.79% (28/39) and 61.54% (24/39), respectively. There were 7 cases of CD200 weak and moderate positive in 10 CHL patients, and ICOS proteins were all negative. Among 10 PTCL-NOS patients, 4 patients had CD200 positive and 1 patient had ICOS positive. The differences in positive rates of ICOS protein between AITL patients and CHL, PTCL-NOS patients were statistically significant (all P < 0.05); the differences in positive rates of CD200 protein between AITL patients and CHL, PTCL-NOS patients were not statistically significant ( χ2=0.013, P=0.911; χ2=3.551, P=0.060). The positive rate of CD200 in AITL patients with elevated lactate dehydrogenase (LDH) and international prognostic index (IPI) score of 3-4 was higher than that in AITL patients with normal LDH and IPI score of 0-2 (both P < 0.05); The positive rate of ICOS in AITL patients with elevated LDH and PD-1 positive was higher than that in AITL patients with normal LDH and PD-1 negative (both P < 0.05). CD200 negative AITL patients had better 3-year overall survival (OS) rate (4.2% vs. 66.7%) and 3-year progression-free survival (PFS) rate (5.3% vs. 77.1%) compared with those in CD200 positive AITL patients, and the differences between both groups were statistically significant (both P < 0.01); there was a statistically significant difference in 3-year OS rate between ICOS positive AITL patients and ICOS negative AITL patients (15.3% vs. 38.6%, P=0.011), while there was no statistically significant difference in 3-year PFS rate of both groups (18.6% vs. 41.5%, P=0.059). Multivariate analysis showed CD200 ( HR=0.076, 95% CI 1.555-79.497, P=0.001), extranodal involvement or not ( HR=11.117, 95% CI 1.555-79.497, P=0.016) and LDH ( HR=2.147, 95% CI 0.844-5.459, P=0.109) were independent influencing factors of OS in AITL patients; CD200 ( HR=0.075, 95% CI 0.016-0.357, P=0.001) and LDH ( HR=2.335, 95% CI 0.929-5.870, P=0.071) were independent influencing factors of PFS in AITL patients. Conclusions:CD200 and ICOS can be used as immunohistochemical indicators to assist the diagnosis of AITL patients. ICOS protein helps to differentiate AITL from CHL and PTCL-NOS; CD200 can be used as indicators to judge the prognosis and deterioration of AITL patients.