Objective Comparing with traditional teaching methods of oral histopathology, to probe whether the interactive teaching system of the digital microscope can improve the teaching effi-ciency of experiment of oral histopathology courses. Methods The subjects were the 2010 grade students (40 students) and the 2011 grade students (38 students) majoring in stomatology of South Medical University, and they were evenly divided into 2 groups at random. In the first part of the ex-periment of Grade 2010, the teaching of traditional optical microscope was used in a group of experi-mental courses, and interactive teaching with digital microscope was used in the other group. In the second part of the experiment the two groups swapped the teaching method. While in the whole exper-iment of Grade 2011, traditional optical microscopes were adopted in one group, and in contrast, the interactive teaching system of the digital microscope was adopted in the other group. The P values of the 5 indexes were less than 0.05. After the courses, the 2010 grade students received the questionnaire survey and the 2011 grade students received the quiz about the experimental course, and then the evaluation results of the two groups were compared for t inspection, using SPSS software t test. Result The questionnaire results of Grade 2010 showed that the scores of digital microscope interactive group were higher than those of traditional teaching group in satisfaction with teaching , teacher-student interaction, classroom atmosphere active degree, learning interest, and the understanding of the teach-ing content. The experiment course content test results of Grade 2011 showed that the digital interactive group students averaged 46.26, while the average score of the traditional teaching group was 42.78%. The difference between the two groups had statistical significance, P=0.001. Conclusion Compared with the traditional teaching methods, the interactive teaching system of the digital microscope can enhance the academic grades, improve the teaching efficiency of experiment of oral histopathology courses, and elevate the teaching quality.

Objective To observe the effect of bromodomain4 (brd4) inhibitor JQ1 on proliferation inhibition and apoptosis of Ph positive acute lymphocytic leukemia (Ph+ ALL) cells, and to explore the influence on the expression of brd4 and its downstream genes (myc and p53), and the reverse effect on bcr-abl.Methods Different concentrations of JQ1 were used on SUP-B15 cells.The proliferation inhibition rate was detected by MTT, the apoptosis rate was determined by flow cytometry (FCM), and the expressions of bcr-abl mRNA, brd4 mRNA, myc mRNA and p53 mRNA were detected by real-time fluorescent quantitative PCR (RT-PCR).Results Different concentrations of JQ1 inhibited SUP-B15 cells proliferation and induced cell apoptosis.The apoptosis rate was significantly increased compared with that in control group with a time-dose dependent manner.Median inhibitory concentration at 72 h was 1.0 pmol/L.At the same time, JQ1 decreased the transcription levels of bcr-abl mRNA, brd4 mRNA and myc mRNA, and increased the transcription level of p53 mRNA.Conclusions As a brd4 inhibitor, JQ1 can decrease the expression of brd4 to affect the expression of its downstream genes myc and p53, meanwhile, it can change the over expression of bcr-abl to suppress the proliferation of Ph+ ALL cells and induce apoptosis.

Objective To establish a PCR sequencing-based typing (PCR-SBT) method for simultaneous genotyping of human platelet antigen HPA-1 to HPA-16w.Methods All DNA polymorphism sites of HPA-1 to HPA-16w were obtained from the immuno polymorphism database.The specific primers were designed using Primer Premier 5.0 software to amplify nucleotide acid fragments encompassing each HPA polymorphism site.The primer sequence and PCR condition were optimized to obtain specific and single amplification product.The PCR product was purified and then sequenced to determine the HPA genotypes.Two standard DNA samples were detected using the HPA PCR-SBT method to examine the accuracy d this method.Sixteen reference samples (including 6 interference samples with HPA gene mutations) provided by 14th platelet immunology workshop of international society of blood transfusion (ISBT) in 2008 were also tested by this home-brew HPA PCR-SBT method.Results Total eleven pairs of primers were designed to amplify and sequence the sixteen HPA systems.The HPA genotypes of two standard samples were 1aa/2aa/3ab/4aa/5ab/6aa/7aa/8aa/9aa/10aa/11aa/12aa/13aa/14aa/15aa/16aa and 1aa/ 2aa/3aa/4aa/5aa/6aa/7aa/8aa/9aa/10aa/11aa/12aa/13aa/14aa/15aa/16aa,respectively.The 256 HPA genotypes of 16 reference samples were clear.128 genotypes among them were completely accordance with the results provided by ISBT report.Conclusions The PCR-SBT assay combining high-throughput DNA sequencer established in the study provides a simple,rapid and accurate method for HPA-1 to HPA-16w systems genotyping.The assay is suitable for routine clinical HPA genotyping and shows a broad prospect in further applications.

Objective To compare the clinical effect of the two surgical methods of posterior pedicle screw fixation decompression in treatment of thoracolumbar burst fractures,and in order to provide the basis for choosing the rational treatment.Methods Retrospectively analyzed the clinical data of 98 patients with thoracolumbar burst fractures underwent surgery of posterior pedicle screw fixation decompression from January 2007 to January 2011.Fifty-six patients were given posterior fixed indirect decompression surgery (indirect decompression group) and 42 patients were given posterior fixed direct decompression (direct decompression group).The patients were followed up for (1.03 ± 0.36) years after surgery,the image,recovery of neurological function,postoperative complications and capacity for independent living of the two groups were compared and evaluated.Results After surgery,the vertebral height ratio,Cobb angle,canal compromise rate in indirect decompression group were (91.67 ± 26.19)％,(10.10 ± 2.89)°,(18.61 ±5.32)％,in direct decompression group were(86.23 ± 24.64)％,(11.98 ± 3.42)°,(22.37 ± 6.39)％.There was significant difference compared with before surgery (P ＜ 0.05) and no significant difference between two groups (P ＞0.05).After surgery,the neurological function of the two groups were improved,and the improvement in indirect decompression group was better than that in direct decompression group (P ＜ 0.05).The postoperative complications ratio in indirect decompression group was 23.2％ (13/56),significantly lower than that in direct decompression group[83.3％(35/42)](x2 =10.370,P＜ 0.01).There was 60.7％(34/56)patients with capacity for independent living in indirect decompression group,significantly higher than that in direct decompression group [40.5％ (17/42)] (x2 =4.329,P ＜ 0.05).Conclusion The posterior pedicle screw fixation indirect decompression in treatment of thoracolumbar burst fractures is a feasible operation method,and is worth to utilize in clinic.

Objective To investigate the serological characteristics and molecular basis of the B (A)phenotype in ABO blood group and provide the data for clinical transfusion of individuals with B(A) phenotype.Methods The ABO group antigens on red cells of the proband,family members and donors were identified by monoclonal antibodies and the ABO antibodies in sera were detected by the standard A,B,O cells.The compatibility testing for the proband and donors was detected by salted test,polybrene test and antiglobulin test.The coding region of exon 6 to exon 7 in ABO gene was amplified by polymerase chain reaction(PCR) and the PCR products were sequenced.The haplotypes of proband were analyzed by cloning and sequencing.Results It was showed that both A and B antigens were detected on red cells of the proband and her two family members,and there was anti-A_1 antibody in their sera.The serological phenotype of the samples are identified as the A_2B.DNA sequencing showed 261 G/del,297A/G,526C/G,657C/T,700C/G,703G/A,796C/A,803G/C,930G/A heterozygotes in exon 6 to exon 7.It can be deduced that genotype in the proband is B(A)_(02)/O_(01).The genotypes of her mother and grandmother-in-law were B(A)_(02)/B_(101) and B(A)_(02)/O_(01),respectively.After cloning and sequencing,two alleles B(A)_(02) and O_(01) in proband was showed.B(A)_(02) has snigle nucleotide change(700 C>G),which resets replacement of proline with alanine at position 234.Two donors with phenotype A_2B were identified as genotype B(A)_(02)/O_(01) and A_(208)/B_(101),respectively.The results of crossmatch testing is in accordane between the proband and two donors and there was no clinical adverse reaction after transfusion.Conclusions 700C>G in α-1,3galactosyltransferase allele(B allde)can result in B(A)phenotype in individuals with the phenotype of A_2B.The donors in the transfusion for the individuals with B(A) phenotype should include individuals with A_2B phenotype.

Objective We performed experiments using Neuregulin-1β (NRG-1β) treatment to determine a mechanism for the protective role derived from its beneficial effects by remodeling gap junctions (GJs) during heart failure (HF). Methods Rat models of HF were established by aortocaval fistula. Forty-eight rats were divided randomly into the HF (HF, n = 16), NRG-1β treatment (NRG, n = 16), and sham operation (S, n = 16) group. The rats in the NRG group were administered NRG-1β (10 μg/kg per day) for 7 days via the tail vein, whereas the other groups were injected with the same doses of saline. Twelve weeks after operation, Connexin 43 (Cx43) expression in single myocytes obtained from the left ventricle was determined by immunocytochemistry. Total protein was extracted from frozen left ventricular tissues for immunoblotting assay, and the ultrastructure of myocytes was observed by transmission electron microscopy. Results Compared with the HF group, the cardiac function of rats in the NRG group was markedly improved, irregular distribution and deceased Cx43 expression were relieved. The ultrastructure of myocytes was seriously damaged in HF rats, and NRG-1β reduced these pathological damages. Conclusions Short-term NRG-1β treatment can rescue pump failure in experimental models of volume overload-induced HF, which is related to the recovery of GJs structure and the improvement of Cx43 expression.

Objective To observe the pathological changes of heart failure caused by transverse aortic constriction in rats.Methods Partial thoracotomy was performed to the second rib and the transverse aortic constriction was performed between the innominate and left carotid arteries to establish a model of heart failure in 24 rats.The same operation was performed on another 8 rats, except for the ligation of the transverse aorta.Echocardiographic assessment, hemodynamic measurement, myocardial histopathological examination and NT-proBNP measurement were performed to the sham group at 12 weeks and model group at 4 weeks, 8 weeks, 12 weeks after the operation.Result At 4 weeks after the operation, NT-proBNP, EF, FS and -dp/dtmax of the model group was significantly increased and LVESV, +dp/dtmax of the model group were significantly decreased (P<0.05).At 8 weeks after the operation, EF and-dp/dtmax of the model group were increased and +dp/dtmax of the model group was significantly decreased (P<0.05).At 12 weeks after the operation, NT-proBNP, EF and +dp/dtmax of the model group were decreased, and LVESV, LVEDV and -dp/dtmax of the model group were increased (P<0.05).The cardiomyocytes became hypertrophic and lined up in disorder at 4 weeks after the operation.Pathologic examination of the myocardial tissue showed connective tissue proliferation and inflammatory cell infiltration at 8 weeks after the operation, and cardiomyocyte apoptosis and collagen fiber deposition at 12 weeks after the operation.Conclusions Transverse aortic constriction induces heart failure in rats.The pathological processes are compensatory hypertrophy at 4 weeks after the operation, initial reaction of decompensation at 8 weeks after the operation, and heart failure at 12 weeks after the operation.

BACKGROUND:It is still a research focus on constructing substitution of the human tissues and organs, or producing the alliance for grafting by engineering methods in tissue engineering. Among these researches, it is pivotal to choose appropriate materials. The prepared scaffolds should have suitable tensile strength and mechanical toughness to withstand the various outside forces without being damaged. So, it is very necessary to evaluate the biomechanical properties of candidated materials in tissue engineering, which can supply the references for selecting materials for tissue scaffolds and their designation.OBJECTIVE: To investigate the biomechanical properties of nine kinds of scaffold materials, in order to supply a biomechanical basis for the selection and design of scaffold materials for tissue engineering.DESIGN: A repetitive measurement study.SETTING: College of Bioengineering, Chongqing University.MATERIALS: The materials involved in this study were poly (DL-lactic-co - glycolic acid) (PLGA), sodium polymannuronate, gelatine, chitosan, collagen, acellular porcine dermis (APD), acellular vascular matrix (AVM),APD-PLGA, AVM-PLGA, modified gelatine and chitosan.METHODS: All the experiments related to this study were completed in the Biorheology laboratory of the College of Bioengineering, Chongqing University from April 2006 to March 2007. The nine materials above were prepared, gelatine and chitosan were modified. Stress-strain testing was performed at 10 mm per minute by a material testing machine (INSTRON 1011, USA). The Yang's modulus was calculated in the range of 0.005 to 0.02, the ultimate strain and stress were also obtained.MAIN OUTCOME MEASURES: The ultimate strain, ultimate stress and Yang's modulus of the nine materials were analyzed.polymannuronate ＞ AVM-PLGA ＞ collagen ＞ gelatine (P ＜ 0.05). The rate of burst straining of chitosan and PLGA were greater than those of other materials, 133% and 276% respectively (P ＜ 0.05). In addition, after being combined with ultimate stresses of APD and APD-PLGA were greater than that of other materials, i.e., their burst strengths were greater than those of other materials. The data also indicated that the burst strength of APD-PLGA was a little greater than that of APD (P ＞ 0.05). The burst strengths of gelatin, chitosan, and collagen were similar at the range of 7.67 to 9.51 MPa (P ＞ 0.05). The burst strengths of collagen and sodium polymannuronate were from 1.16 to 1.40 MPa, which were the least among all the materials. At the same time, being combined with PLGA, the burst strength of AVM-PLGA greatest, i.e., its rigidity was the greatest. The rigidity of APD was the least. After combined with PLGA, the rigidity of AVM and APD were increased (P ＜ 0.05), and corresponded with PLGA (P＞ 0.05). Except for gelatin, the order of rigidity in the materials was AVM-PLGA ＞ PLGA ＞ APD-PLGA ＞ AVM ＞ chitosan ＞ sodium polymannuronate ＞ collagen ＞ APD.CONCLUSION: AVM and APD have good biomechanical properties, which are very different from the water-soluble collagen. It is promising to improve the biomechanical properties of sodium polymannuronate, gelatin and chitosan by the complex of PLGA.

In order to explore the reason why hypokalemia could increase the vulnerable window (VW) for unidirectional conduction block in Long QT Syndromes (LQTS), we observed the effect of hypokalemia on the spatial gradients of Na channel conductance (G(Na)) and gating factors by using the LR91 1-dimensional heterogeneous virtual cardiac ventricular tissue model quatitively. The computer simulation experiments were divided into two groups, namely control and LQTS groups. The action potential was elicited after the basic stimulus S1 (-70 microA/microF, 1.5 ms) was given 10 times with basic cycle length (BCL) 500, 1000 and 2000 ms. To test the VW in unit of time (VWtime), the S1-S2 programmed stimuli were used with shortening S1S2 interval at the decrement of 1 ms. At the same time, the spatial gradients of Na channel conductance (G(Na)) and gating factors, m, h, j, were investigated. The APD and ionic channel currents were also detected under the conditions of normal and lower concentration of K+ outside of cell. We found that hypokalemia, LQTS and slow pacing rate enhanced the spatial gradient of G(Na) by increasing the spatial gradient of inactive gating factors h x j. The results also showed that hypokalemia deduced the peak values of I(K) and I(K1), which prolonged the action potential duration and enlarged the repolarization dispersion in this 1-D tissue cable model. Possibly these are the important factors to cause the spatial gradient of h x j and G(Na). enlargement. These changes increase the incidence of unidirectional conduction block of VW, and are vital reasons to increase the possibility of ventricular arrhythmia generation.
Computer Simulation ; Extracellular Space ; metabolism ; Humans ; Hypokalemia ; metabolism ; Long QT Syndrome ; etiology ; metabolism ; physiopathology ; Models, Biological ; Myocardium ; metabolism ; Sodium Channels ; metabolism

Objective To investigate the efficacy and safety of transcatheter arterial chemoembolization (TACE) combined with CT-guided thermal ablation (radiofrequency ablation or microwave ablation) in treating intrahepatic cholangiocarcinoma.Methods The clinical data of 14 patients with pathologicallyproved intrahepatic cholangiocarcinoma,who were admitted to authors' hospital during the period from September 2009 to July 2013 to receive TACE with subsequent radiofrequency ablation (RFA) or microwave ablation (MWA),were retrospectively analyzed.A total of 18 lesions were detected in the 14 patients.The maximal diameter of the lesion (or the sum of maximal diameters if there were multiple lesions) ranged from 2.2 cm to 7.2 cm (mean 4.2±1.4 cm).After TACE,the lesion's complete ablation rate,surgical complications,tumor-free survival time and overall survival time were evaluated.Results Complete ablation was obtained in 15 lesions (83.3％,15/18).The incidence of moderate complications was 6.2％,and no severe complications or death occurred.After the treatment,the patients were followed up for 6-14 months,with a mean of (16.0±10.3) months.At the end of follow-up,6 patients (42.9％,6/14) died.The median tumor-free survival time in patients whose lesions obtained complete ablation was 17 months.The median survival time of all patients was 20 months.The 1-,2-and 3-year overall survival rates were 82.5％,41.3％ and 20.6％ respectively.Conclusion TACE combined with thermal ablation can be regarded as one of the treatment options for intrahepatic cholangiocarcinoma.