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 diagnostic efficacy and clinical value of GNB4 and Riplet gene methylation alone and in combination in the diagnosis of primary liver cancer.Methods A total of 313 patients were selected,including 78 patients with primary liver cancer,41 patients with other digestive system tumors,17 patients with non-digestive system tumors,20 patients with postoperative liver cancer,and 157 patients with benign liver disea-ses.The levels of GNB4 and Riplet gene methylation in plasma were detected using quantitative methylation-specific PCR(qMSP).Serum alpha-fetoprotein(AFP)levels were measured by direct chemiluminescence.Results The sensitivity and specificity of AFP in diagnosis were 51.3％and 94.3％,respectively;the sensitivity and specificity of GNB4 gene methylation in diagnosis were 83.3％and 99.4％,respectively;the sensitivity and specificity of Riplet gene methylation in diagnosis were 73.1％and 99.4％,respectively.The sensitivity and specificity of GNB4 and Riplet gene methylation combined diagnosis were 92.3％and 98.7％,respectively;the sensitivity and specificity of AFP,GNB4 and Riplet gene methylation combined diagnosis were 92.3％and 98.7％,respectively;the sensitivity and specificity of combined diagnosis including age and gender were 93.6％and 97.5％,respective-ly.Conclusion The sensitivity and specificity of AFP in the diagnosis of primary liver cancer are limited,while the methylation levels of GNB4 and Riplet genes are higher,and the sensitivity and specificity of their combined de-tection are higher than those of AFP.The sensitivity and specificity of AFP,GNB4 and Riplet gene methylation combined diagnosis are significantly higher than those of AFP,GNB4 and Riplet gene methylation alone.

Objective To evaluate the value of cardiac MR imaging in chronic ischemie mitral regurgitation (IMR) in patients with myocardial infarction. Methods All patients clinically diagnosed with coronary heart disease and myocardial infarction in our hospital from January 2016 to September 2018 were retrospectively selected, myocardial infarction time more than 3 months and confirmed to have necrotic myocardium by cardiac magnetic resonance examination. All patients underwent echocardiography at the same time. Based on the results of echocardiography, patients were divided into the myocardial infarction group without IMR (40 cases), the mild IMR group (39 cases) and the moderate to severe IMR group (51 cases). Cardiac MR and delayed enhancement (LGE) scan images were analyzed. Cardiac function indexes were measured and left ventricular LGE positive segments were recorded. The indexes of myocardial global longitudinal strain (GLS), global peripheral strain (GCS) and global radial strain (GRS) of left ventricle of IMR patients were measured by feature tracking(FT). Cardiovascular history, coronary artery stenosis and location of myocardial infarction were compared by chi?square test between the without IMR, mild IMR and moderate to severe IMR groups.Univariate analysis of variance was used to compare the measurement data of left ventricular myocardial infarction volume, left heart function and left ventricular myocardial globle strain, and LSD test was used for pair?wise comparison. Results There was no difference in age, sex and cardiovascular history among the three groups. Comparison of myocardial infarction patients in the three groups: (1) There was no statistically significant difference in the myocardial infarction volume between the three groups (P=0.052), while the myocardial infarction volume tended to increase as the grade of mitral regurgitation increased. The number of patients with myocardial infarction in the inferior wall and the inferolateral wall in the moderate to severe IMR group were significantly higher than those of the other two groups (P<0.05), and there was no significant difference in the volume of myocardial infarction between the without IMR group and mild IMR group, and no difference in the number of patients with inferior wall and inferolateral wall. (2) Cardiac function measured by CMR: ejection fraction (EF) was significantly reduced in the moderate to severe IMR group compared with the without IMR group and the mild IMR group (P<0.05), the end diastolic volume (EDV) increased significantly and the end systolic volume (ESV) increased significantly (P<0.05). Mass of myocardium increased significantly (P<0.05); Stroke volume (SV) and cardiac output (CO) there was no significant difference among the three groups. (3) Comparison of the moderate to severe IMR group to the without IMR group and the mild IMR group respectively: left ventricular GLS and GRS decreased (P<0.05), the difference of the GCS was no statistically significant. There was no statistical difference in the three strain values between the without IMR group and the mild IMR group. Conclusion The globe myocardial strain of the left ventricle in myocardial infarction patients with chronic moderate to severe IMR was significantly impaired, the myocardial infarction in the inferior wall and the inferolateral wall in the level of the papillary muscle may be correlated with chronic moderate to severe IMR, and the myocardial infarction volume of the left ventricle may also be related.

Objective: To evaluate the value of cardiac MR imaging in chronic ischemie mitral regurgitation (IMR) in patients with myocardial infarction. Methods: All patients clinically diagnosed with coronary heart disease and myocardial infarction in our hospital from January 2016 to September 2018 were retrospectively selected, myocardial infarction time more than 3 months and confirmed to have necrotic myocardium by cardiac magnetic resonance examination. All patients underwent echocardiography at the same time. Based on the results of echocardiography, patients were divided into the myocardial infarction group without IMR (40 cases), the mild IMR group (39 cases) and the moderate to severe IMR group (51 cases). Cardiac MR and delayed enhancement (LGE) scan images were analyzed. Cardiac function indexes were measured and left ventricular LGE positive segments were recorded. The indexes of myocardial global longitudinal strain (GLS), global peripheral strain (GCS) and global radial strain (GRS) of left ventricle of IMR patients were measured by feature tracking(FT). Cardiovascular history, coronary artery stenosis and location of myocardial infarction were compared by chi-square test between the without IMR, mild IMR and moderate to severe IMR groups.Univariate analysis of variance was used to compare the measurement data of left ventricular myocardial infarction volume, left heart function and left ventricular myocardial globle strain, and LSD test was used for pair-wise comparison. Results: There was no difference in age, sex and cardiovascular history among the three groups. Comparison of myocardial infarction patients in the three groups: (1) There was no statistically significant difference in the myocardial infarction volume between the three groups (P=0.052), while the myocardial infarction volume tended to increase as the grade of mitral regurgitation increased. The number of patients with myocardial infarction in the inferior wall and the inferolateral wall in the moderate to severe IMR group were significantly higher than those of the other two groups (P<0.05), and there was no significant difference in the volume of myocardial infarction between the without IMR group and mild IMR group, and no difference in the number of patients with inferior wall and inferolateral wall. (2) Cardiac function measured by CMR: ejection fraction (EF) was significantly reduced in the moderate to severe IMR group compared with the without IMR group and the mild IMR group (P<0.05), the end diastolic volume (EDV) increased significantly and the end systolic volume (ESV) increased significantly (P<0.05). Mass of myocardium increased significantly (P<0.05); Stroke volume (SV) and cardiac output (CO) there was no significant difference among the three groups. (3) Comparison of the moderate to severe IMR group to the without IMR group and the mild IMR group respectively: left ventricular GLS and GRS decreased (P<0.05), the difference of the GCS was no statistically significant. There was no statistical difference in the three strain values between the without IMR group and the mild IMR group. Conclusion The globe myocardial strain of the left ventricle in myocardial infarction patients with chronic moderate to severe IMR was significantly impaired, the myocardial infarction in the inferior wall and the inferolateral wall in the level of the papillary muscle may be correlated with chronic moderate to severe IMR, and the myocardial infarction volume of the left ventricle may also be related.