Correlation between expression of Lin28B and C-myc in patients with laryngeal squamous cell carcinoma and clinicopathological features and prognosis / 中南大学学报(医学版)

OBJECTIVES@#Laryngeal squamous cell carcinoma (LSCC) is a common malignant tumor of head and neck. Screening of target genes for malignant tumor therapy is one of the focuses of cancer research, with proto-oncogene and tumor suppressor gene as the breakthrough. It has become an urgent need to find the target gene related to the treatment and prognosis of LSCC.This study aims to explore the role of Lin28B and C-myc in LSCC by detecting the expressions of these two proteins and analyze the correlation between the expression of Lin28B and C-myc and clinicopathological features and prognosis of LSCC.@*METHODS@#We detected the expression of Lin28B and C-myc proteins in 102 specimens of LSCC and 90 specimens of adjacent tissues by immunochemistry, and analyzed the correlation between Lin28B and C-myc protein expressions in LSCC as well as the correlation between the expressions of the two proteins and the clinicopathological features of LSCC. At the same time, the Kaplan-Meier method was used to analyze the relation between Lin28B and C-myc protein levels with the postoperative survival rate of LSCC patients.@*RESULTS@#The protein levels of Lin28B and C-myc in the LSCC tissnes were significantly higher than those in the adjacent tissues (both P<0.05),and there was a positive correlation between the expression of Lin28B and C-myc in LSCC (r＝0.476, P<0.05). The expression of Lin28B protein was closely related to age, lymph node metastasis, clinical stage, tumor size, and pathological differentiation of LSCC patients (all P<0.05). while the expression of C-myc protein was closely related to lymph node metastasis, clinical stage, tumor size, and pathological differentiation of LSCC patients (all P<0.05). A relevant survival analysis showed that in patients with higher level of Lin28B (P＝0.001) or C-myc protein (P<0.001), the postoperative survival rate was relatively low.@*CONCLUSIONS@#Lin28B and C-myc proteins are highly expressed in LSCC with a positive correlation. Furthermore, they are closely related to lymph node metastasis, clinical stage, tumor size, pathological differentiation and prognosis, suggesting that both Lin28B and C-myc might be involved in the occurrence and development of LSCC.

Influence of thermal effect on filling effect of bioceramic paste in different parts of root canal / 国际生物医学工程杂志

Objective:To study the effect of thermal effect on the filling effect of bioceramic paste combined with thermal gel gutta-percha vertical obturation method in different parts of root canal.Methods:Forty single-root canal teeth samples were randomly and randomized divided into the control group, the iRoot SP group, the 10 s group and the 20 s group. All tooth samples were root canal prepared to 0.04 taper after crown removal. The control group received AH-plus paste combined with thermal gel gutta-percha vertical obturation. The iRoot SP group received iRoot SP single-point filling. The 10 s group and 20 s group received iRoot SP single-point filling combined with thermal gel gutta-percha vertical obturation, in which the root canal of the two groups were heated at 180 °C for 10 s and 20 s, respectively, before using the thermosetting gutta-percha. Methylene blue staining, scanning electron microscope (SEM) observation and dental microscope observation were used to analyze the occurrence of gaps in the middle and upper segment of the root canal and the apical 1/3 of the root canal after filling.Results:For the filling in the apical 1/3 of the root canal, no obvious gap appeared in the 10 s group and the 20 s group, and there was no significant difference between the dye infection depth and the control group (all P>0.05). For the filling of the middle and upper segment of the root canal, the probability of porosity is higher when using iRoot SP combined with single-point filling. Conclusions:Short-term high temperature heating will not affect the sealing effect of iRoot SP on the apical 1/3 of the root canal. For the middle and upper segment of the root canal, the filling effect of iRoot SP single-point filling combined with thermal gel gutta-percha vertical obturation method is better than that of iRoot SP single-point filling.