In view of the weakness of the teachers' strength, students' lack of interest and the lack of unity of teaching materials in the foreign language teaching, Oral Medicine College of Chongqing Medical University carried out the reform to the professional foreign language courses in the postgraduate education period by strengthening the preparation of special teaching materials, reinforcing teaching staff construction, reforming teaching methods and creating a learning environment. The results of teaching assessment by students and peer-reviewers show that reform has achieved good results, and aiming at the problems in the teaching practice we also put forward such improvement measures as strengthening the student-centered teaching method, promoting new teaching methods and optimizing curriculum assessment programs.

By establishing a series of Dynamic Cervical Implants (DCI) within C5-C6 cervical spinal segments, the biomechanical finite element analysis for DCI with different width and thickness were carried out to investigate the influence of the width and thickness of DCI's curved section on its equivalent stress and range of motion (ROM), so as to provide some theoretical basis for the optimization of DCI's design. The results show that the width of DCI's curved section has more obvious influence on the ROM of lateral bending and torsion, in comparison with the thickness of DCI's curved section. By appropriate reduction in width, the ROMs of lateral bending and torsion increase obviously, i.e. the overall movement function of patients is improved. Furthermore, the increase of equivalent stress could be counteracted by corresponding increase of thickness.
Biomechanical Phenomena ; Cervical Vertebrae ; Finite Element Analysis ; Humans ; Movement ; Neck ; Prostheses and Implants ; Prosthesis Design ; Range of Motion, Articular

OBJECTIVEThis study measures the glutaredoxin (Grx) gene and protein expression in umbilical vein endothelial cells upon exposure to Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS). The involvement of the Akt-signaling pathway is also determined.

METHODSEA-hy926 cells were pretreated with 1,000 ng · mL⁻¹ P. gingivalis LPS for 4, 12, 18, and 24 h, and then real-time reverse transcription polymerase chain reaction was employed to detect Grx1 expression. The effect of Grx on Akt activity was investigated using Western blot for the control, LPS (1,000 ng · mL⁻¹ LPS), and carmus- tine (BCNU) groups (1,000 ng · mL⁻¹ LPS, and the EA-hy926 cells were pretreated with 25 μmol · ml⁻¹ BCNU for 30 min).

RESULTSGene expression of Grx1 significantly increased in LPS group compared with that in the control group. The Grx1 expression reached the peak level in 12 h, and the variation between the expression in 4 and 12 h was significant (P < 0.05). After 12 h, the protein levels of Grx and phosphorylated-Akt (p-Akt) significantly increased in the LPS group (P < 0.05), whereas the BCNU group showed a considerable decrease in both Grx and p-Akt expression levels (P < 0.05). Moreover, a slight difference was observed in the total Akt protein levels in the three groups (P > 0.05).

CONCLUSIONGrx expression increased upon exposure of EA-hy926 cells to the LPS. Akt activity could be inhibited by BCNU (a Grx inhibitor), which indicated that Akt might act as a downstream regulator of Grx.

Endothelial Cells ; Glutaredoxins ; genetics ; Humans ; Lipopolysaccharides ; pharmacology ; Oxidative Stress ; drug effects ; Phosphorylation ; Porphyromonas gingivalis ; pathogenicity ; Proto-Oncogene Proteins c-akt ; drug effects ; Signal Transduction ; drug effects ; Umbilical Veins

BACKGROUND: Root canal files fracture is a kind of common oral clinical complications. Therefore, it is of clinical importance to study the cyclic fatigue of different types of stainless steel root canal files.OBJECTIVE: To explore the effect of the bending angle and cross-sectional area of root canal instruments on cyclic fatigue of stainless steel files.METHODS: Thirty 25# stainless steel K files (25 mm in length) were selected, the same to 30# and 35#. And these three kinds of files were respectively randomized into three groups (n=10 per subgroup). In the nine subgroups, the files were placed into self-made root canals at the bending angle of 45°, 60°, 90°, and driven by a 16:1 reducer (350 r/min).Fracture time in each subgroup was recorded and converted into the number of rotations. The microstructure of the fracture end of the files was observed under scanning electron microscope. Fractured files were collected and the crack tip length was measured by an electronic caliper.RESULTS AND CONCLUSION: At the same bending angle, the number of rotations resulting in file fracture was significantly reduced with the increasing of the cross-sectional area of the files (P < 0.05). When the type and cross-sectional area were same, the number of rotations resulting in file fracture was significantly reduced with the increasing of the bending angle of the root canals (P < 0.05), indicating a reduction in the cyclic fatigue performance of the files. Toughness fracture occurred in all the files, and circular or oval roughness nests with different sizes and microcavities formed on the fracture surface. In addition, brittle surfaces could be detective between the roughness nests. The diameter of roughness nests was gradually increased with the increasing of the bending angle of the root canals. For 30# and 35# files, the number of brittle surfaces was gradually increased with the increasing of the bending angle of the root canals. For 25# files, the crack tip length was gradually decreased with the increasing of the bending angle of the root canals, but there was no significant difference (P > 0.05). For 30# and 35# files, the crack tip length was significantly shortened with the increasing of the bending angle of the root canals (P < 0.05). But there were no significant changes in the 35#-60° and 35#-90° groups (P=0.095). At the same bending angle, there were no regular changes in the crack tip length in the different types of files. In conclusion, with the increasing of the cross-sectional area, the cyclic fatigue performance of the files with the same length and taper is reduced and the files become easy to be fractured; with the increasing of the bending angle of the root canals, the files with the same types are apt to be fractured near the root tip, indicating the shorter length of the crack tip indicates the more difficulty in the removal of the broken files.

Objective To analyze the effect of Shuxuetong injection on microcirculation in patients with septic shock and its therapeutic effect. Methods A prospective study was conducted. Eighty patients with septic shock treated in Department of Critical Care Medicine of Hebei Provincial Traditional Chinese Medical Hospital were randomly divided into a Shuxuetong group and a conventional therapy group according to random number table, 40 cases in each group. The conventional treatment in the two groups was energetically carried out in accord to the sepsis shock guidelines, such as positive fluid resuscitation, anti-infection, etc. In the Shuxuetong group, additionally Shuxuetong injection 6 mL in 5% glucose injection 250 mL intravenous drip was given once a day for 7 days. The levels of urine output, lactic acid (Lac), blood urea nitrogen (BUN), creatinine (Cr), aspartate aminotransferase (AST), alanine aminotransferase (ALT), left ventricular ejection fraction (LVEF), and cardiac index (CI) in the two groups were observed before and after treatment; the total dosages of dopamine, dobutamine, noradrenaline, etc. vascoactive agent used for the patients and 28-day mortality in the two groups were also recorded. Results The comparisons of levels of urine output, Lac, BUN, Cr, AST, ALT, LVEF, and CI before treatment between the two groups were of no statistical significant differences (all P>0.05). After treatment in the two groups, the urine output, LVEF, and CI were increased compared with those before treatment, whereas the Lac, BUN, Cr, AST, and ALT were significantly decreased, and the changes were more obvious in Shuxuetong group [urine output (mL/h):112.1±39.8 vs. 73.3±28.5, LVEF:0.49±0.15 vs. 0.44±0.14, CI (mL·s-1·m-2):66.2±5.7 vs. 54.2±6.2, Lac (mmol/L):3.83±1.65 vs. 4.72±2.25, BUN (mmol/L):7.1±2.7 vs. 9.3±3.5, Cr (μmol/L): 73.9±16.2 vs. 95.7±15.8, AST (U/L): 39.8±9.5 vs. 45.8±12.7, ALT (U/L):34.3±9.7 vs. 41.7±11.3, all P<0.05]. The total dosages of all kinds of vascoactive agent of Shuxuetong group were remarkably less than those in the conventional therapy group [dopamine (mg): 993.1±261.7 vs. 1 340.9±356.4, dobutamine (mg):776.2±281.0 vs. 1 049.2±364.3, noradrenaline (mg):56.4±34.6 vs. 107.6±51.3, all P<0.05]. The 28-day mortality of Shuxuetong group was obviously lower than that of conventional therapy group [40.0%(16/40) vs. 60.0%(24/40), P<0.05]. Conclusion Shuxuetong injection can improve the microcirculation perfusion in patients with septic shock and reduce their mortality.

BACKGROUND:Distraction osteogenesis is one of the most important tissue engineering technologies. However, the exact signaling pathway controling mesenchymal stem cel-osteoblast lineage (MSC-OB) migration during distraction osteogenesis has not yet been elucidated. More efforts should be paid to make a ful understanding of the mechanism on MSC-OB lineage migration, which can improve the clinical efficacy of distraction osteogenesis.
OBJECTIVE:To evaluate the effects of mechanical stretch on the ability of MSC-OB mobility and expression of mammalian target of rapamycin (mTOR) signaling pathway as wel as matrix metaloproteinases (MMPs) in MSC-OB, and to make clear the mechanism by which controls MSC-OB migration during distraction osteogenesis.
METHODS:Twelve Sprague-Dawley rats were randomized into two groups: experimental group (n=6), anin vivo rat mandibular distraction osteogenesis model was established on the right side of rats; non-stretch group (n=6), only the mandibular resection was done but with no distraction osteogenesis. Immunohistochemical staining was used to detect phosphorylated mTOR expression in new osteotylus at 15 days after operation. In addition, an in vitro cel stretch model was made in the mandibular mesenchymal stem cels from healthy Sprague-Dawley rats under resting tension force (6%, 4 hours); no distraction was done in control group. The ability of MSC-OB mobility, the expression of mTOR, Raptor, p70S6K and MMPs were evaluated using experiment methods including immunohistochemistry staining, real-time PCR and scratch assay.
RESULTS AND CONCLUSION: The expression of phosphorylated mTOR in MSC-OB was upregulated in the mandibular bone calus of the stretch group than the non-stretch group (P < 0.05). In thein vitro experiments, MSC-OB applied with mechanical stretch (6%, 4 hours) showed elevated gene expression levels of mTOR, Raptor, p70S6K, MMP-2, MMP-9 and MMP-13 compared with the control group (0%, 4 hours). Meanwhile, MSC-OB in the experiment group (6%, 4 hours) showed a greater ability of mobility, as demonstrated by a farther distance after 48 hours of observation (P < 0.05). The present study suggests that the enhancement of MSC-OB mobility correlates with increase of the gene expression of MMPs and mTOR signaling pathway. Mechanical stretch may promote MSC-OB migration through activation of mTOR/MMPs signaling pathway.

Objective: To explore the consumption of sugar sweetened beverages (SSBs) and its association with behavioral problems in Chinese preschool children, and to provide a scientific basis for the prevention of behavioral problems of children. Methods: A total of 7 634 children aged 3-6 years were chosen from kindergartens in 3 cities (Yangzhou, Xuzhou, Zhenjiang) in the lower reaches of Yangtze River using method of cluster sampling during October to November in 2017. Parental or guardian questionnaires were used to obtain information regarding child consumption of SSBs. The Strengths and Difficulties Questionnaire (SDQ) was used to assess children s emotional and behavioral problems. Multivariate Logistic regression model was used to explore the association between different SSBs intake frequency and children s behavioral problems. Results: A total of 5 509(72.2%) consumed SSBs less than once a day, 830(10.9%) reported SSBs consumption once a day, and 1 295(16.9%) had 2 times or more intake of sugar sweetened beverages per day. After adjusting for confounding factors including age, sex, BMI, family financial status, parental education, screen time, sleep duration, and physical activities duration, multiple Logistic regression model revealed that intake of SSBs once a day was associated with an increased risk of hyperactivity disorder ( OR =1.26, 95% CI =1.01-1.57) and SDQ total difficulties ( OR =1.44, 95% CI =1.14-1.82) in boys and with an increased risk of emotional symptoms ( OR=1.34, 95%CI =1.02-1.76), conduct problems ( OR=1.53, 95%CI =1.18-2.00), hyperactivity disorder ( OR=1.79, 95%CI =1.42-2.27) and prosocial behavior ( OR=1.48, 95%CI =1.14-1.91) in girls. Intake of SSBs≥2 times per day was associated with an increased risk of emotional symptoms ( OR=1.28, 95%CI =1.02-1.59) and SDQ difficulties ( OR=1.30, 95%CI =1.07-1.58) in boys and not with behavioral problems in girls. Conclusion Sex differences are observed with respect to the association between SSBs intake and behavioral problems in preschoolers, but no significant dose response relationship was observed. More longitudinal studies are needed to further explore the association between SSBs intake and behavioral problems in preschool children as well as the underlying physiological mechanisms in future.

OBJECTIVETo investigate the effect of vascularized composite flap with iliac crest and nternal oblique muscle of abdomen for half mandibular reconstruction.

METHODSFrom July 2009 to Sept. 2013, 14 cases with half mandibular defect after tumor resection were treated with composite flap of iliac crest and internal oblique muscle of abdomen pedicled by deep circumflex iliac vessels. During operation, one group performed tumor resection and got the recipient area vessels ready for anastomosis. The other group performed harvesting of composite flap. Then the flap was trimmed and fixed to construct the defect with vessel anastomosis.

RESULTSAll the 14 composite flaps survived with local infection only in 1 case. The size of harvested iliac crest ranged from 6 cm x 3 cm to 9 cm x 3 cm. The size of harvested internal oblique muscle of abdomen ranged from 5 cm x 4 cm to 7 cm x 5 cm. The patients were followed up for 6 months to 26 months (mean, 13 months) with satisfactory results and no complication. Mandibular panoramic radiographs showed new bone formation and good union.

CONCLUSIONSVascularized composite flap with iliac crest and internal oblique muscle of abdomen has the advantages of abundant bone volume, as well as soft tissue reconstruction in one stage. The reconstructed mandible can attain normal function and appearance.

Abdominal Muscles ; transplantation ; Abdominal Wall ; Humans ; Ilium ; transplantation ; Mandibular Reconstruction ; methods ; Reconstructive Surgical Procedures ; methods ; Surgical Flaps ; blood supply ; transplantation

Objective To determine the expression of TM4SF1 mRNA in 5 human pancreatic cancer cell lines,and investigate its effect on the proliferation,migration and invasion of pancreatic cancer cells.Methods The expression of TM4SF1 mRNA in MPanc96,MiaPaCa-2,PANC1,AsPC-1,HPAC cells was determined by qRT-PCR,and the results were compared with that of human pancreatic ductal epithelial (HPDE) cells.RNA interference method was used to transiently transfect siRNA targeting at TM4SF1 and negative control siRNA into MPanc96,MiaPaCa-2 cells.The proliferation of cells were measured by MTS method,and migration and invasion of cells were determined by Transwell.Results The expression levels of TM4SF1 mRNA in pancreatic cancer cell lines MPanc96,MiaPaCa-2,PANC1,AsPC-1 and HPAC were 1.205 ± 0.073,1.096 ± 0.260,1.382 ± 0.075,1.374 ± 0.363 and 0.744 ± 0.096,which were significantly highly than that in HPDE (0.020 ± 0.003,P ＜ 0.01).Compared with cells transfected with negative control siRNA,the proliferation of MPanc96 and MiaPaCa-2 cells transfected with siRNA targeting at TM4SF1 was not significantly changed,but the migration abilitiy was decreased by (62.5 ± 7.6) ％ and (72.8 ± 4.0) ％,and invasion abilitiy was decreased by (69.5 ± 5.7) ％ and (78.6 ± 6.3) ％.Conclusions TM4SF1 is highly expressed in pancreatic cancer cells and appears to promote the migration and invasion abilities of the cancer cells.

Objective To investigate the application value of identification of the scalp surface locations of cerebral ischemia lesions before direct revascularization for moyamoya disease and to design surgical approaches according to this by using the fusion of single photon emission computed tomography ( SPECT) cerebral perfusion imaging with CT imaging. Methods The clinical data of 13 adult patients with ischemic-type moyamoya disease underwent superficial temporal artery-middle cerebral artery bypass surgery were analyzed retrospectively. SPECT cerebral perfusion imaging was fused with CT imaging of the same machine before procedure. The lesions of ischemia were located on the cortical surface. The surgical approaches were designed at the center of the ischemic lesions. The patients were followed up for 6 to 12 months after procedure. The improvement of clinical symptoms and cerebral perfusion of the patients were observed after operation. Results One patient had perioperative cerebral hyperperfusion syndrome,and the others did not have any perioperative complications. At one-month follow-up, the improvement of symptoms in 4 patients were excellent,in 5 were good,in 4 were fair,and none was poor. At 6 to 12 month follow-up,the improvement of symptoms in 9 patients were excellent,in 4 were good,and none was poor. The postoperative visual SPECT cerebral perfusion imaging analysis suggested that the cerebral perfusion was improved significantly as compared with before procedure in all patients. Quantitative analysis:There was significant difference in target ischemic lesions between preoperative Fb and postoperative Fb ([2. 13±1. 06]% vs. [4. 13±2. 09]%;P<0. 05). There was significant difference between preoperative Fb and Fe ([2. 46±1. 97]% vs. [2. 13±1. 06]%;P<0. 05). The postoperative BFCR was [67. 57±3. 78]%( >50%) , which indicated that the efficacy of the procedure was remarkable. The superficial temporal arteries fed to brain of the patients were observed after procedure by using the head CT angiography. The postoperative head MRI reexamination showed no new infarcts occurred at 6 months. Conclusion Combine SPECT cerebral perfusion imaging with CT imaging to design surgical approach for superficial temporal artery-middle cerebral artery bypass surgery may improve the efficacy and reduce the risks of operation.