Aim To find out the relationship between muscarinic receptor and reactive oxygen species (ROS) and the probable differences between the four muscarinic receptor subtypes. Methods We transfected the plasmid encoding muscarinic receptor (including subtypes: M_1, M_2, M_3 and M_4) into PC12 cells. Then PC12 cells were exposed to hydrogen peroxide (H_2O_2), carbachol and other inhibitors such as atropine, LY294002 and PD98059. Results The results showed that activation of muscarinic receptor by carbachol protected PC12-M_1, PC12-M_2,PC12-M_3 and PC12-M_4 cells from apoptosis induced by H_2O_2. There was no statistical difference in the protective effect between these four muscarinic receptor subtypes. By using the inhibitors, we found that atropine and LY294002 blocked the protective effect of activation of muscarinic receptor on apoptosis induced by H_2O_2. Conclusion Activation of muscarinic receptor retarded the apoptosis induced by H_2O_2. There was no difference between the four muscarinic receptor subtypes. The protective effect was mainly mediated by the activation of muscarinic receptor and phosphatidylinositol-3 kinase (PI3K).

AIM: To Screen and identify differentially expressed genes that involved in apoptosis model in rat cerebellar granule neurons (CGNs).METHODS: The rat cerebellar granule neurons were isolated and primarily cultured. Fluorescent differential display RT-PCR (FDD RT-PCR) was performed to screen differentially expressed ESTs in the apoptosis model of primarily cultured rat CGNs. ESTs were subcloned into pGEM-T EasyTM vector and then sequenced. Alignment assay in non-redunant database was applied for encoding information. Reverse Northern blotting was used to appraise the results from DDRT-PCR.RESULTS: 164 pieces of differentially expressed ESTs were obtained by FDDRT-PCR. 17 of them were subcloned and sequenced. 5 ESTs of 17 were confirmed to be positive results by reverse Northern blotting. CONCLUSION: DD-PCR is a rapid, simple-operation and sensitive method for screening differentially expressed genes, which would contribute to the molecular mechanisms of apoptosis/survive of CGNs.

AIM: To clone the full-length of 75A EST. METHODS: After the extraction of total RNA from primary cultured rat cerebellar granule cell of 7DIV in the medium containing 25 mmol/L KCl, T_4 DNA ligase-mediated 5' RACE was used to retrieve 5' unknown sequence of 75A EST, and the first round 5' RACE PCR product was subcloned into pGEM-T easy vector for sequence and homogeneous analysis. RESULTS: The first round of 5' RACE produce a 2.5 kb band, and 75A EST was identified to be partial sequence of Neuron-derived orphan receptor (Nor1) gene. After two more rounds RACE, we firstly cloned the full-length of Nor-1 cDNA. CONCLUSION: T_4 DNA ligase mediated 5' RACE is an efficient method to retrieve information about the 5' termini of mRNAs, and lay a foundation for further study which role Nor1 play in the cerebellar granule cell differentiation or survive.

Objective:To examine the expression of programmed cell death 1 (PD-1) and its ligand (PD-L1) in epithelial ovarian cancer (EOC) tissues, and investigate the correlation among their expression, clinicopathological features and prognosis.Methods:The specimens of 180 patients with EOC treated in the First Affiliated Hospital of Dalian Medical University from October 2002 to December 2013 were confirmed by pathological examination. The pathological tissue specimens of subtypes ，included 120 cases of serous carcinoma, 30 cases of mucinous carcinoma, 20 cases of endometrioid carcinoma, and 20 cases of clear cell carcinoma. The normal paracancerous tissues of 50 cases randomly selected from the 180 patients as control group. Immunohistochemical SP method was used to detect the expressions of both PD-1 and PD-L1 in epithelial ovarian cancer tissues, and the relationships among their expressions,the clinicopathological parameters and prognosis were respectively analyzed.Results:（1） PD-1 was expressed in lymphocytes infiltrated in EOC tissues, and PD-L1 was expressed in the cell membranes of cancer tissues. In all EOC cases, 33 cases (18.3%, 33/180) of both PD-1 and PD-L1 were highly expressed, and only 1 (2.0%, 1/50) of control group showed high expression. There was statistically significant difference between two groups ( P<0.01). (2) Among the four subtypes tissue specimens of EOC, the high expression rate of PD-1 was 25.0% (30/120) for serous carcinoma, 3/15 for endometrioid carcinoma, 0 (0/30) for mucinous carcinoma, and 0 (0/15) for clear cell carcinoma. The high expression rate of PD-L1 was 23.3% (28/120) for serous carcinoma, 3.3% (1/30) for mucinous carcinoma, 2/15 for endometrioid carcinoma, and 2/15 for clear cell carcinoma. Both PD-1 and PD-L1 expressions in the four sub-types of tissue specimens were significantly different ( P<0.05). The high expression rate of both PD-1 and PD-L1 was 9.2% (8/87) in the early stage and 26.9% (25/93) in the late stage. There was a statistically significant difference between the two groups ( P<0.01). Similarly, the expression of both PD-1 and PD-L1 were significantly higher in the cases of high-grade EOC （type Ⅱ） than those of low-grade （type Ⅰ） and in the cases of EOC distributed bilaterally than that distributed unilaterally, and there were statistically significant differences ( P<0.05). (3) The Kaplan-Meier survival analysis showed that the survival time were respectively 35 and 36 months in the cases with high expressions of both PD-1 and PD-L1, and the survival time were the same as 61 months in the cases with low expression of both PD-1 and PD-L1, and the comparison was statistically significant ( P<0.05). Conclusions:The expression levels of PD-1 and PD-L1 in EOC tissues are higher than those in adjacent tissues, especially in serous carcinomas. The expression of both PD-1 and PD-L1 is higher in specimens of the patients with advanced stages. The results showed that the high expression of both PD-1 and PD-L1 is an indicator of poor prognosis of patients suffering from EOC.

Objective:To investigate the diagnostic value of thyroid imaging report and data system (TIRADS) combined with BRAF V600E mutation detection in differentiating uncertain thyroid nodules by using fine needle aspiration cytology (FNAC), and to analyze the role of TIRADS classification in screening the nodules needed to be routinely detected for BRAF V600E mutation.Methods:The clinicopathological data of 337 thyroid nodules patients diagnosed with TIRADS classification, FNAC Bethesda classification, BRAF V600E mutation detection and postoperative histopathology from the Second Hospital of Hebei Medical University between January 2018 and August 2021 were retrospectively analyzed. The role of TIRADS classification, FNAC Bethesda classification and BRAF V600E mutation detection alone and the combined detection in the differentiation of benign and malignant thyroid nodules was also analyzed.Results:The postoperative histopathological result was regarded as the gold standard. The sensitivity of TIRADS classification, FNAC Bethesda classification and BRAF V600E mutation for thyroid cancer diagnosis was 76.0%, 88.1% and 80.4% respectively, and the corresponding specificity was 84.0%, 96.0% and 100.0%, respectively. Histologically, 37 (62.7%) of 59 nodules with FNAC uncertainty were malignant nodules after the surgery. The sensitivity and accuracy of BRAF V600E mutation detection in the diagnosis of FNAC uncertain nodules were 51.4% and 69.5%, respectively, while the sensitivity and accuracy of BRAF V600E mutation detection combined with TIRADS classification were 86.5% and 84.7%, respectively. The sensitivity and accuracy of BRAF V600E mutation detection combined with TIRADS classification were both improved ( P values were 0.002 and 0.049, respectively). The positive rate of BRAF V600E mutation in thyroid nodules increased step by step with the rise of risk degree in TIRADS classification, and the type 3 cases were lower than those in type 4a cases [14.3% (1/7) vs. 68.6% (24/35), P = 0.012], and there were no statistically significant differences among the adjacent groups above 4a (all P > 0.05). Conclusions:TIRADS combined with BRAF V600E mutation detection can improve the sensitivity and accuracy in the diagnosis of FNAC uncertain thyroid nodules. The BRAF V600E mutation rate of TIRADS 4a and above nodules is high, so routine detection is recommended.