BACKGROUND:Obturation with warm gutta-percha can achieve perfect three-dimensional root canal obturation effect. Due to specific structure of oval canal, particularly in the bypass preparation process, excessive cutting of local tooth tissue may lead to tooth tissue thinning and irregular shape. The separation equipment is the metal with good heat conduction, so the heat caused by the bypassing warm gutta-percha obturation would burn periodontal tissue remains controversial. OBJECTIVE:To investigate the changes of root surface temperature produced by two bypassing warm gutta-percha obturation for the separation instrument in oval canalin vitro by using infrared thermography. METHODS:Forty mandibular first premolars were harvested from oval canals, and were separated using stainless steel 15# K file at apical 3 mm, with the length of 3 mm. The root canal bypassing was prepared using TF nickel-titanium file under operating microscope. The teeth were randomly divided into two groups, with 20 teeth in each group, and were obturated with the Thermafil warm gutter-percha and E&Q plus warm gutta-percha vertical compaction, respectively. An infrared thermoviewer was used to measure the external root surface temperature before and after the obturation. RESULTS AND CONCLUSION:Two warm gutta-percha obturation methods used for separating instruments bypassing in the oval root canal, had both caused the rise of root surface temperature, which was less than 10℃. In the Thermafil group, the temperature changes were 3.2-8.1℃ and the average change was 4.97℃. In the vertical condensation group, the temperature changes were 5.5-9.8℃ and the average change was 7.35℃. There were significant differences in the change of root surface temperature between the two groups (P < 0.05). Thermafil warm gutter-percha obturation would increase the root surface temperature, but cannot damage periodontal tissues. It is more secure than warm gutta-percha vertical condensation.

Objective To observe the effect of Sini decoction on inflammatory response and immune function in septic rats and to discuss its possible mechanism.Methods 66 Sprague-Dawley (SD) rats were randomly divided into normal control group (n=6),model group (n=30),and Sini decoction group (n=30).Septic model was reproduced by intraperitoneal injection of lipopolysaccharide (LPS,5 mg/kg).After the reproduction of sepsis,rats in Sini decoction group received Sini decoction (5 g/kg) by gavage,while those in model group were given equal dose of normal saline in the same way.Rats in normal control group did not receive any treatment.Blood was collected via eye sockets at 2,12,24,48,72 hours after LPS administration,then the rats were sacrificed.The concentrations of inflammatory mediators,such as interleukin (IL-1,IL-6,IL-10),tumor necrosis factor-α (TNF-α),and the expression level of monocyte human leukocyte antigen-DR (HLA-DR) were determined with enzyme linked immunosorbent assay (ELISA),and the pathological changes in intestinal mucosa were observed under electron microscope.Results The concentration of IL-1 (ng/L) at 2 hours in model group was gradually increased and peaked at 48 hours (4.07 ± 0.10),and then gradually decreased,while the IL-1 level in Sini decoction group peaked at 12 hours (2.98 ± 0.12) followed by a gradual decrease.IL-6 (ng/L) in model and Sini decoction groups peaked twice at 12 hours (91.39 ± 1.55,73.00 ± 2.38) and 48 hours (82.51 ± 1.49,64.68 ± 1.68) respectively.IL-10 (ng/L) in model group gradually decreased after peaking at 2 hours (86.66 ± 6.12),and that in Sini decoction decreased at 12 hours (71.61 ± 2.35) followed by an increasing tendency,and approached normal level at 48 hours (109.09 ±4.77 vs.124.01 ± 7.89,P＞0.05).TNF-α (ng/L) in model group was gradually increased and peaked at 48 hours (83.37 ±3.79),and that in Sini decoction peaked at 12 hours (48.52 ± 1.21),and decreased to normal level at 72 hours (18.59 ± 1.97 vs.15.50 ± 2.68,P＞0.05).During the course of the experiment,as compared with those of the model group,level of IL-1,IL-6,and TNF-α were significantly lower at all time points in Sini decoction group,and IL-10was significantly higher.The expression level of HLA-DR (μg/L) in model and Sini decoction groups peaked at 2 hours (4.86 ± 0.15,4.85 ± 0.17),and then gradually lowered.HLA-DR expression μg/L) at 48 hours and 72 hours in Sini decoction group was significantly lower than that in model group (48 hours:4.21 ± 0.12 vs.2.74 ± 0.16,72 hours:3.80 ± 0.09 vs.2.27 ± 0.12,both P＜0.01).Pathological study of intestinal mucosa showed that the intestinal mucosa were infiltrated significandy by inflammatory cells,and villi were damaged severely in both model group and Sini decoction group at 2 hours after LPS challenge.Infiltration of inflammatory cells in Sini decoction group was less intense after 12 hours,and the intestine villi repair was more obvious compared with model group.Conclusion Sini decoction could regulate systemic inflammatory response,and promote the repair of intestinal mucosa,the intestinal function and the immune status of septic rats.

Objective To study the appropriate neck irradiation volume for neck lymph nodenegative nasopharyngeal carcinoma patients by Meta-analysis.Methods The related references published from Jan 1990 to Jun 2013 were searched in Pubmed,Embase,Cochrane and Wangfang Databases.The qualified references for enrollment criteria were screened and the relative data were collected.The OR (Odds ratio) value by fixed effect model was used to evaluate the data for patients who received radiotherapy between the upper neck and whole neck irradiation.The endpoints including 5-year neck local control rate (LCR),neck-in-irradiation LCR,and neck-outsides-irradiation LCR.Results Five qualified references were screened and belonged to respective research.There enrolled 1 333 patients,including 970 patients who received the upper neck irradiation and 363 patients who received the whole neck irradiation,respectively.The forest plots revealed that there were no significant differences for 5-year neck LCR,neckin-irradiation LCR,and neck-outsides-irradiation LCR for patients received radiotherapy between the upper neck and whole neck irradiation.These OR values were 0.89 (95％ CI:0.41-1.94),1.29 (95％ CI:0.58-2.88) and 0.42 (95％ CI:0.07-2.36),respectively.Conclusions The Meta-analysis results suggest that irradiation to the upper neck for neck lymph node-negative nasopharyngeal carcinoma can be appropriate.

BACKGROUND:Many experiments have demonstrated that tissue engineering scaffolds prepared by polymer materials alone or biomaterials cannot meet the requirement of tissue engineering research.
OBJECTIVE:To evaluate biological characteristics and cel affinity of poly(hydroxybutyrate-co-hydroxyoctanoate)/col agen composite scaffold.
METHODS:Tissue engineering scaffolds were prepared by combination of poly(hydroxybutyrate-co-hydroxyoctanoate) and col agen at different proportions (2%, 4%, 6%, 8%and 10%) using solvent casting/particulate leaching method. Inner structure and apertures were observed by scanning electron microscope, and the porosity was determined by liquid displacement method. Rabbit chondrocytes were co-cultured with poly(hydroxybutyrate-co-hydroxyoctanoate)/col agen composite scaffold and poly(hydroxybutyrate-co-hydroxyoctanoate) scaffold. Growth curve of cel s was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and cel adhesion on the scaffolds was observed by scanning electron microscope.
RESULTS AND CONCLUSION:The pore size and porosity of the composite scaffold were about 200μm and (85±2)%, respectively. The cel affinity dynamical y increased with the increasing of proportion of col agen. Compared with the poly(hydroxybutyrate-co-hydroxyoctanoate) scaffold, the poly(hydroxybutyrate-co-hydroxyoctanoate)/col agen composite scaffolds are better to improve cel adhesion and proliferation, with favorable cel ular affinity.

Objective To investigate the efficiency and safety as well as the effect of chronic intravenous iron supplementation on the improvement of anemia in the patients with maintain hemodialysis (MHD). Methods Fifty-six patients with MHD were involved in the six-month, controlled trail and randomly divided into two groups: intravenous iron group (IV group) and oral iron group (oral group). The patients of IV group (n=28) were intravenously pumped 100 mg iron dextran during each hemodialysis session for the total amount of 1000 mg,after that,100 mg iron dextrin each two weeks. Patients in the oral group took 525 mg ferrous sulfate a day during the first three months and received iron dextran on the above methods under stopping oral iron supplement during the second three months. The efficacy was assessed by determining the change of hemoglobin (Hb), hematocrit (Hct), serum ferritin (SF) and transferring saturation (TSAT). Results The levels of Hb, Hct, SF, TSAT were increasing in the IV group after trail and there were evidently difference in those markers in the first three months, compared to the oral group, P

OBJECTIVE To observe and compare the cytotoxicity induced by andrographolide (AD)and its water soluble derivatives:andrographolide sodium bisulfite(ASB),active pharmaceutical ingredients of Chuanhuning and Yanhuning on human renal tubular epithelial cells (HK-2),and to explore the ASB-induced endoplasmic reticulum stress(ERS)mechanism. METHODS HK-2 cells were treated with the above four drugs respectively. The survival rate was examined by methyl thiazolyltetrazolium (MTT) assay and 50% inhibitory concentration (IC50) was calculated. In ASB treated group, Hoechst33342 staining and flow cytometry analysis were used to determine cell apoptosis, intracellular superoxide dismutase(SOD)activity and malondialdehyde(MDA)content were examined, and the protein expressions of binding immunoglobulin protein (Bip),C/EBP-homologous protein (CHOP)and cysteine-containing aspartate-specific protease 4(caspase 4)were detected by Western blotting. RESULTS The four drugs inhibited HK-2 cell growth in a time-dependent and concentration-dependent manner. At 24 h,the IC50 of AD (30.6 μmol · L- 1) was lower than that of others. Active pharmaceutical ingredients of Chuanhuning and Yanhuning (16.2 and 15.6 mmol · L- 1) were very close,ASB was 29.4 mmol · L-1. ASB(0,15,30 and 60 mmol · L-1)increased the apoptotic rate and caused the decrease in SOD activity and the increase in MDA content in a dose-dependent manner. Compared with control group,the protein expression of CHOP increased (P<0.01) at 8 h with ASB (30 and 60 mmol · L-1)treatment,Bip and caspase 4 had no significant change. In addition,at 24 h, ASB(60 mmol·L-1) decreased the expression of Bip(P<0.05),ASB(30 and 60 mmol·L-1)promoted the expression of CHOP(P<0.01),and the protein expression of activated caspase 4 increased in a concentration-dependent manner(P<0.01). CONCLUSION AD and its water soluble derivatives have a toxic effect on HK-2 cells. CHOP and caspase 4 pathway related to ERS is involved in ASB-induced apoptosis.

Objective To compare the effects of propofol and ketamine on long-term memory and the expression of brain N-methylgroup-D-aspartate receptor 2B(NMDAR2B) and Gamma-aminobutyric acid receptor 1(GABAR1) in aged rats, and preliminary investigate the relation between the long-term memory and expression of neurotransmitter receptors in different cerebral areas. Methods The aged male rats were randomly divided into control group,propofol group and ketamine group. Morris water maze training was performed in all the rats of three groups for 5 days. On the 6th day, intraperitoneal injection of 50 mg?mL-1 propofol was administrated in propofol group,80 mg?mL-1 ketamine was intraperitoneally injected in ketamine group,and blank control group was given the same dose of saline.Seven days after the administration,space exploration experiment and navigation experiment test were performed to test the impact on the learning and memory ability of rats. After that, the expression levels of GABAR1 and NMDAR2B in temporal lobe and hippocampal CA1 region of the rat brain were detected by immunofluorescence and FISH technique. Results The results of Morris water maze showed there was no significant difference between propofol group (9.49±1.24) s and blank control group (8.82±2.22) s.There was statistically significant difference between ketamine group (12.04±2.67) s and blank control group (P<0.05),with longer latency time and less number of times of passing through target as compared with blank control group.By using immunohistochemistry and FISH technique,the expression of GABAR1 in temporal lobe and hippocampal CA1 region of the rat brain was not significantly different between propofol group and blank control group,but it was significantly up-regulated in ketamine group as compared with blank control group ( P<0.05) . The expression of NMDAR2B in temporal lobe and hippocampal CA1 region of the rat brain was not significantly different between propofol group and blank control group,but it was significantly down-regulated in ketamine group as compared with blank control group (P<0.05). Conclusion Propofol anesthesia alone had no effect on long-term learning and memory,but ketamine anesthesia can result in long-term learning and memory impairment. The mechanism may be related with down-regulation of the expression of NMDAR2B receptor and up-regulation of GABAR1 not only in CA1 region hippocampus,but also in temporal lobe.

BACKGROUND:Due to the complexity and irregularity of bypass obturation of oval root canal and the particular stress of the post and core to the tooth, we have not yet found a reasonable post crown for dental restoration after bypass obturation of the oval root canal.
OBJECTIVE:To compare the flexural capacity of the three kinds of post-and-core repair systems (cobalt-chromium cast post and core, zirconium oxide post and core, and CAD/CAM-fabricated glass fiber post and core) after bypass obturation of the oval root canal warm gutta.
METHODS: Ninety mandibular first premolars were selected for bypass obturation of the root canal with Obtura II & System B, and then randomized into three groups that were respectively restored with cobalt-chromium cast post and core, zirconium oxide post and core and CAD/CAM-fabricated glass fiber post and core. After that, cobalt-chromium metal crown was used for ful-crown restoration. Fracture strength and fracture type were recorded in different groups.
RESULTS AND CONCLUSION: The fracture resistance was higher in the cobalt-chromium cast post and core group and zirconium oxide post and core group than the glass fiber post and core group (P < 0.05), and the former two groups had no significant difference. Cobalt-chromium cast post and core was fractured at the root of tooth, and could not be repaired; the zirconium oxide post and core was fractured at the root neck and root of tooth, which was confirmed as reparative fracture; the glass fiber post and core was fractured at the tooth neck, which could be restored. These findings indicate that the cobalt-chromium cast post and core can bear greater occlusal force, but has a higher probability of root fracture; the CAD/CAM-fabricated glass fiber post and core exhibits a lower probability of root fracture

BACKGROUND:Currently, there are many studies on colapsed repair, but a systematic and horizontal comparison is not reported yet. OBJECTIVE: To compare the effect of conventional resin adhesive, resin adhesive+silane coupling agent and adjacent surface open part of the crown on colapsed repair through clinical trial and in vitro experiment. METHODS: (1) Clinical trial: 90 patients with porcelain colapse were randomized into three groups, and respectively treated with conventional resin adhesive, resin adhesive+silane coupling agent and adjacent surface open part of the crown. Success rate was measured and compared among three groups at 1 year after repair. (2) In vitro test: Twenty test specimens were equaly divided into two groups, and treated with conventional resin adhesive and resin adhesive+silane coupling agent, respectively. Then, shear strength was detected in the two groups. Twenty double-crown specimens were equaly divided into four groups. The first three groups were treated with sand blasting, silane coupling agent and their combination treatment, respectively; the rest group had no treatment (control group). After repair, the tensile strength of each specimen was detected.RESULTS AND CONCLUSION:The success rate of colapsed repair was 37% for conventional resin adhesive, 90% for resin adhesive+silane coupling agent and 100% for adjacent surface open part of the crown. The shear strength was (13.978±0.343) MPa for the conventional resin adhesive and (10.058±0.64) MPa for resin adhesive+silane coupling agent, and there was a significant difference between two methods (P < 0.01). The tensile strength was (0.68±0.04) kN in the control group, (1.00±0.02) kN in the sand blasting group, (1.31±0.08) kN in silane coupling agent group, and (1.09±0.04) kN in the combination group, and there was a significant differences between groups (P < 0.01). Experimental results show that the silane coupling agent+resin adhesive treatment and adjacent surface open part of the crown are superior to conventional resin adhesive.