OBJECTIVETo explore a simple but novel method of strengthening gypsum material by cyanoacrylate infiltration. To evaluate the influence of cyanoacrylate on the mechanical properties of dental gypsum models.

METHODSGypsum specimens were polished to the dimension of 35 mmx4 mmx4 mm. Butyl-cyanoacrylate was diluted with chloroform at different concentrations, namely 20% and 30% cyanoacrylate. Gypsum specimens were infiltrated by diluting one component of cyanoacrylate at different concentrations for 8 h and then dried for analysis. The changes in elastic modulus, fracture toughness, compressive strength, biaxial strength, brinell hardness were measured. The data were analyzed using software OriginPro 8.

RESULTSThe viscosity measurements indicated that diluted cyanoacrylate were Newtonian fluids and the viscosity increased slightly within the 48 hours of preparation but still similar as water at room temperature, which could be used to infiltrating gypsum. The gypsum infiltrated with cyanoacrylate exhibited good physicochemical properties. The biaxial strength, fracture toughness, compressive strength and brinell hardness of the gypsum were improved by 39%, 30%, 63% and 18%, respectively.

CONCLUSIONCyanoacrylate can significantly improve the strength of gypsum model which indicates the potential clinical application.

BACKGROUNDAppropriate planning and staffing for medical services at large-scale athletic events is essential to provide for a safe and successful competition. There are few well-documented accounts describing the demand for such services. The present study provided the data from the Beijing 2008 Olympics and Paralympics, with a view to provide the guidance for planning future events.

METHODSA total of 22 029 and 8046 patients, who received medical care from a physician at an Olympic or Paralympic medical station, were included. The patient proportion among different personnel, various disease proportions at different kinds of venues, and the disease spectrum at specified venues at the Olympics and Paralympics were analyzed.

RESULTSAt both games, the patient proportion varied by accreditation status. The staff accounted for the largest number of visits at the Olympics (44.83%) and Paralympics (36.95%), with respiratory diseases the most common. Various disease spectrums were discovered at the different kinds of venues. Surgical diseases were the most frequently listed reason for visits, both at competition and non-competition venues, especially during the Paralympics. The sport-related injuries accounted for a majority of the surgical cases during both games. At training venues, ear nose and throat diseases accounted for the greatest number of visits during both games.

CONCLUSIONSDuring both games, people contracted different diseases at different venues. Adequate surgeons should be designated to offer assistance mostly in trauma situations. Appropriate numbers of physicians in respiratory diseases and otorhinolaryngology is of great importance.

BACKGROUND: With the development of biotechnology, the electrophysiology of repairing heart tissues of myocardial infarction or myocardial hypertrophy by using bone marrow mesenchymal stem cell has become a hot spot. OBJECTIVE: To overview the research progress of cardiac electrophysiological characteristics after transplantation of induced differentiation of bone marrow mesenchymal stem cells into cardiomyocytes. METHODS: The databases of PubMed, Springer Link, Science Direct and CNKI were retrieved for papers published from January 2000 to October 2010 with the key words of bone marrow mesenchymal stem cells, cardiac/heart, electrophysiology/electrophysiological characteristics. The relevant articles concerning cardiac electrophysiological characteristics of induce differentiation and transplantation of bone marrow stem cells were collected. RESULTS AND CONCLUSION: Totally 208 papers have been searched. Preliminary screening by reading abstracts to exclude 162 papers that study purpose do not coincident with this review either contents duplicated, and internalized 46 papers at last. Bone marrow mesenchymal stem cells after induced differentiation and transplantation could improve heart function of animal experimental model and myocardial infarction or myocardial hypertrophy patients. Although the cardiomyocyte-like cells from bone marrow mesenchymal stem cells could help to improve heart function, the cardiac electrophysiological characteristics may be influenced by them.

Breast Neoplasms ; genetics ; pathology ; Chromosome Aberrations ; Chromosome Deletion ; Chromosomes, Human, Pair 1 ; Chromosomes, Human, Pair 17 ; Chromosomes, Human, Pair 9 ; Female ; Genome, Human ; Humans ; Nucleic Acid Hybridization ; methods ; Phyllodes Tumor ; genetics ; pathology

AIM: To investigate the apoptosis and molecular mechanism of human hepatocellular carcinoma HepG2 cells induced by ginsenoside Rh4.METHODS: Human hepatocellular carcinoma HepG2 cells were treated with ginsenoside Rh4 at doses of 10, 20 and 40 μmol/L, and the inhibitory effect of ginsenoside Rh4 on HepG2 cell viability was measured by MTT assay.The apoptotic rate of HepG2 cells was analyzed by flow cytometry.The morphological changes of the HepG2 cells were observed by Hoechst 33258 and TUNEL staining.The expression of apoptosis-related proteins Bax, Bcl-2, caspase-3 and caspase-9 was determined by Western blot.RESULTS: Ginsenoside Rh4 promoted apoptosis of HepG2 cells in a dose-dependent manner.TUNEL and Hoechst 33258 staining showed that the cells appeared obvious shrinking, swelling and rupture after treated with ginsenoside Rh4 for 24 h.The results of Western blot showed that with the increasing concentrations of ginsenoside Rh4, the expression of pro-apoptotic proteins Bax, cleaved caspase-3 and caspase-9 increased, while anti-apoptotic protein Bcl-2 decreased gradually.CONCLUSION: Ginsenoside Rh4 induces apoptosis of human hepatocellular carcinoma HepG2 cells, and the main mechanism may be related to down-regulation of Bcl-2 and up-regulation of Bax, cleaved caspase-3, and caspase-9.

BACKGROUND: Previous studies demonstrated that construction of eoexpression plasmid containing multiple genes on the same vector could improve transfection and expression rates.OBJECTIVE: To construct eukaryotic expression plasmid pcDNA3.1 (+)-MUC1 -GM-CSF by human polymorphic epithclial mucin (MUC 1) and granulocyte macrophage colony stimulating factor.(GM-CSF) and to observe expression of recombinant plasmid in COS-7 cells.DESIGN,TIME AND SETTING: Gene recombination design,which was carried out in the Animal Central Laboratory,the Fourth Military University of Chinese PLA from September 2005 to December 2006.MATERIALS: Eukaryotic expression vector pcDNA3.1 (+) was presented by Pro.Taylor-Papadimitriou;pGEM-3zf()-GM-CSF plasmid,COS-7 cells,pUCI 8 vector,and E.coli DH5α were made in the center; female BALB/c mice were provided by Experimental Animal Center of the Fourth Military University of Chinese PLA.METHODS: Signal peptide was synthesized with encoded MUCI gene sections to obtain repeated sequence coneatemer after renaturation.Next,the accepted concatemer was cloned with GM-CSF following enzyme identification and sequencing analysis,and then they were put in eukaryotic expression vector pcDNA3.1(+) to construct eukaryotic coexpression plasmid pcDNA3.1 (+)-MUCI -GM-CSF in order to transform COS-7 cells.MAIN OUTCOME MEASURES: Gene expression was detected by indirect immunofluorescence and enzyme linked immunosorbent assay (ELISA).RESULTS: Enzyme identification and sequencing analysis showed that recombinant plasmid contained a fusion gene encompassing human MUC1 repeated sequence concatemer and GM-CSF; moreover,MUC1 expression was detected in COS-7 cells,while recombinant plasmid could induce the production of anti-GM-CSF antibody.CONCLUSION: The recombination between human MUC1 repeated sequence concatemer and GM-CSF gene successfully constructs eukaryotic coexpression plasmid.

Objective To prospectively evaluate the feasibility and reliablity of low kilovoltage contrast-enhanced multi-slice CT(MSCT)to detect the myocardial viability in chronic myocardial infarcetion.with comparison to magnetic resonance(MR)myocardial perfusion and viability imaging.Methods Thirty-two patients with clinical diagnosed chronic myocardial infarction underwent the first pass and delayenhanced myocardial imaging with 64-slice MSCT and MR Left ventricle was divided into 16 segments.MSCT and MR images of all the patients were blindly analyzed.The size and extent of hypoenhanced regions in first pass phase and hyperenhanced regions in delayed phase were define.The Kappa test was used to assess the ability of identifying the viable myocardium between the two methods.Results In 32 patients with chronic myocardial infarction,MSCT showed hypoenhanced regions in 41 segments and normal in 471 segments during the first phase,while MRI revealed hypoenhanced regions in 47 segments and normal regions in 465 segments.The Kappa value was 0.650 and the concordance rate of the two techniques was 94.5%(484/512).MSCT showed 135 hyperenhanced regions which were non-transmural in 50 segments and transmural in 85 segments.And the other 377 normal segments showed no enhancement in the delayed phase.MRI revealed 120 hyperenhanced regions which were non-transmural in 56 segments and transmural in 64 segments.And the other 392 normal segments showed no enhancement in the delayed phase.The Kappa value of the two techniques was 0.609 and the concordance rate of the two techniques was 80.7% (413/512).Conclusion The study showed that low kilovolrage CE MSCT has a good concordance with MRI and has high feasibility and reliability in evaluating the myocardial viability in chronic myocardial infarction.The radiation dose is still the important aspect of MSCT application.

Objective To study the difference in pathogenicity and genotype between two isolates of Veronaeae botryosa with different temperature tolerance. Methods Two strains of Veronaeae botryose were isolated from two patients with phaeohyphomycosis in Jiangsu and Henan province respectively. Of them, the Jiangsu strain could grow well at 37 ℃, but Henan strain could not grow at 36 ℃. Eighty mice were equally classified into immunocompetent and immune-suppressed (induced by cyclophosphamide) groups to be inoculated with the two strains of Veronaeae botryosa respectively. Ten mice remained uninoculated and served as the control. The general condition, growth and organic involvement of mice were observed for 4 weeks followed by the killing of surviving mice. Homogenated tissue samples were obtained from liver, spleen, lung, kidney and brain; then, tissue culture, direct microscopy and pathological examination were performed. Genomie DNA was extracted from tissue samples and subjected to random amplified polymor-phic DNA (RAPD) analysis. PCR was performed to amplify the intemal transcribed spacer (ITS) of rDNA followed by sequencing Results Systemic phaeohyphomycosis was induced in both immunocompetent and immune-suppressed mice by the Jiangsu strain of Veronaeae botryose; the mortality was 30% in immune-competent mice and 65% in immune-suppressed mice with statistical significance between the two groups. In immune-suppressed mice inoculated with the Jiangsu strain, the infection rate was 100% in the lung,signifi-cantly higher than in other organs; on direct microscopy the infection rate reached 64.7% in the liver, and 70.5% on tissue culture. There was no significant difference in the infection rate among these organs in immunocompetent mice inoculated with the Jiangsu strain, with the infection rate being 57.8% in the lung and 42.1% in the liver. Increased infection rate was observed in the lung of immune-suppressed mice com-pared with immunocompetent mice (P < 0.05). No definite infection was seen in immunoeompetent or immune-suppressed mice innoculated with the Henan strain. RAPD analysis and sequencing revealed that there was a base variation (A/G) at position 236 of ITS gene between the two strains. Conclusions The two strains of Veronaeae botryosa have different genotypes. Systemic phaeohyphomycosis can be caused in immunocompetent and immuno-suppressed mice by the Veronaeae botryosa isolate from Jiangsu Province; the mortality was higher in immuno-suppressed mice than in immunocompetent mice. The pathogenicity of Veronaeae botryose is associated with the immune status of hosts. In immuno-suppressed mice, lung is the organ most susceptible to infection by Veronaeae botryosa.

Objective To evaluate low-dose CT coronary angiography with prospective electrocardiogram (ECG)-triggering using dual-source CT scanner.Methods Sixty-eight patients who underwent coronary CT angiography using a dual-source CT scanner were divided into 2 groups: group A (38 cases) and group B (30 cases).Prospective ECG-triggering sequence scan mode was employed for group A.Inclusion criteria included: heart rate <70 bpm, sinus rhythm, and heart rate fluctuation less than 10 bpm.Data acquisition was set at 70% of the RR-interval.Retrospective ECG-gating helical scan was performed for group B.Inclusion criteria included heart rates < 70 bpm and sinus rhythm.The exclusion criteria included heart failure and serious arrhythmias.In both groups, patients with a BMI≥24 kg/m2 were examined with a tube voltage of 120 kV, whereas patients with a BMI <24 kg/m2 were examined with a tube voltage of 100 kV.All images were transferred to a workstation for further processing and analysis.The imaging quality was evaluated.The imaging quality of coronary artery segments were compared with rank sum test between the two groups, and the radiation dose were compared with t test.Results A total of 476 coronary artery segments were evaluated in group A and 372 segments were evaluated in group B.The mean score of imaging quality for coronary artery segments in group A was 3.48±0.59 and that in group B was 3.53±0.58.There was no statistical difference in imaging quality between the two groups (Z=-1.432, P=0.187).The effective dose was on average (2.51±0.54) mSv (range 1.3--3.3 mSv) in group A, whereas on average (14.55±3.54) rosy (range 7.1--20.2 mSv) in group B.There was a statistical difference between the two groups (t=18.484, P=0.000).Conclusions Low-dose prospective ECG-triggering sequence scan in dual-source CT coronary angiography is feasible in patients with low heart rate and regular cardiac rhythm.This scan mode can substantially reduce radiation doses while preserving good diagnostic image quality.

Background Visual electrophysiology is a sensitive index for the evaluation of visual function.It has an important value in the assessment of traumatic optic neuropathy.Rabbit is an ideal animal model of traumatic optic neuropathy,and it is simple for the record of flash visual evoked potential(F-VEP)in rabbits.ObjectiveThe present study is to establish the animal model of traumatic optic neuropathy with or without lens injury and observe the repairing procedure using F-VEP. MethodsModels of traumatic optic neuropathy associated with lens injury were established in the right eyes and only traumatic optic neuropathy were created in the left eyes of 64 healthy SPF Chinese white rabbits using fluid percussion brain injury device(FPI).F-VEP was recorded based on the Proposal of International Visual Electrophysiology on 1,2,4,7,10,14,21,28 days after injury of optic nerves.Experimental animals were sacrificed in above time points for the histopathological examination.Macrophages were labeled by ED-1 antibody and survival retinal ganglion cells (RGCs)were stained by Nissl method.Results At the first day after injury,the latencies of P_(100) in both group were longer,and the amplitudes of P_(100) in both group were lower than before injury,showing statistically significant differences among different time points(P<0.05),but no significant difference was seen between the two groups(P>0.05).The duration of latency in traumatic optic neuropathy associated with lens injury group was shorter than that in only traumatic optic neuropathy group(P<0.05).The restore of latency in traumatic optic neuropathy associated with lens injury group was much faster than that in only traumatic optic neuropathy group(P<0.05).The numbers of macrophages were significantly increased and numbers of survival RGCs were considerably decreased with lapse of injury time (P<0.05).The abnormalities of VEP P_(100) and RGCs were obviously improved in 28 days after injury in both groups. ConclusionThis animal model can be established successfully by FPI.The result of retinal histopathological examination confirms F-VEP findings in this model.