BACKGROUND:Computer-assisted implant surgery can improve implantation accuracy,but the use of implant template in the posterior tooth area is limited for patients with small opening and small interocclusal distance.Therefore,the digital guide has been improved. OBJECTIVE:To study the effect of modified implant template on the accuracy of assisted implantation in missing second molars. METHODS:From July 2020 to July 2023,40 patients who received digital guide plate implantation or free hand implantation to repair missing second molars were selected from First Affiliated Hospital of Guangzhou Medical University.According to the coin toss method,patients were randomly divided into a trial group(n=22;modified digital guide assisted implantation)and a control group(n=18;free hand implantation).The data of neck deviation,tip deviation,depth deviation,and angle deviation were compared between groups for preoperative and postoperative cone beam CT overlap analysis.One week after the operation,the patients'satisfaction with the operation was assessed by visual analog scale score. RESULTS AND CONCLUSION:(1)The trial group included 25 implants(12 in the upper jaw and 13 in the lower jaw);the control group included 23 implants(8 in the upper jaw and 15 in the lower jaw).The neck deviation,tip deviation,depth deviation,and angle deviation of the trial group were all smaller than those of the control group(P<0.05,P<0.001).There was no significant difference in accuracy between the maxillary and mandibular implant site in the trial group(P>0.05).(2)There was no significant difference in satisfaction with the operation between the two groups(P>0.05).(3)The results showed that improving the digital guide plate for assisted implantation for missing second molar can improve surgical accuracy and is suitable for patients with small opening and small interocclusal distance in the posterior tooth area.

AIM:To investigate the role of BRCA2 and CDKN1A interacting protein(BCCIP)in gastric can-cer(GC)and elucidate its mechanism in mediating cisplatin resistance.METHODS:The BCCIP mRNA expression was assessed in GC tissues(n=415)and normal tissues(n=34)using The Cancer Genome Atlas(TCGA)database.In an in-ternal cohort(n=36 for RT-qPCR;n=5 for Western blot;n=30 for immunohistochemistry),BCCIP expression at both mRNA and protein levels was examined in GC tissues and paired adjacent normal tissues.Human GC cell lines AGS and HGC27 were cultured in vitro and treated with cisplatin in a dose(0,2,4,6,8 and 10 μmol/L)-and time(0,6,24 and 48 h)-dependent manner,followed by Western blot analysis of BCCIP expression.Stable BCCIP knockdown cell lines(shRNA#1 and shRNA#2 groups)were generated via lentiviral transfection,with empty vector-transfected cells serving as controls(vector group).Flow cytometry and colony formation assay were performed to evaluate the effects of BCCIP on apoptosis and colony-forming ability of GC cells treated with cisplatin.Western blot was utilized to detect the changes of BCCIP protein expression levels in the cytoplasm and nucleus of GC cells after cisplatin(2.5 and 1.0 μmol/L)treatment,as well as the effects of BCCIP on the expression of DNA damage marker γ-H2AX and apoptosis-related proteins cleaved caspase-9 and cleaved caspase-3,and the activation of checkpoint kinase 1(CHK1)after cisplatin(2.5 and 1.0 μmol/L)treatment.Immunofluorescence was conducted to observe the effect of BCCIP on γ-H2AX expression in GC cells treated with cisplatin(2.5 and 1.0 μmol/L).RESULTS:The BCCIP expression was significantly up-regulated in GC tissues compared with normal tissues(P<0.01).Cisplatin induced up-regulation of BCCIP expression in a dose-and time-depen-dent manner.Knockdown of BCCIP significantly enhanced cisplatin-induced apoptosis(P<0.01)and reduced colony-forming ability(P<0.05)of GC cells.Knockdown of BCCIP promoted the expression of γ-H2AX,but inhibited the activa-tion of CHK1 after cisplatin treatment,with increased protein levels of cleaved caspase-9 and cleaved caspase-3(P<0.01).CONCLUSION:Cisplatin promotes the expression of BCCIP in GC cells.BCCIP confers cisplatin resistance in GC cells by suppressing apoptosis through modulation of DNA damage response pathways.

AIM:To investigate the role of BRCA2 and CDKN1A interacting protein(BCCIP)in gastric can-cer(GC)and elucidate its mechanism in mediating cisplatin resistance.METHODS:The BCCIP mRNA expression was assessed in GC tissues(n=415)and normal tissues(n=34)using The Cancer Genome Atlas(TCGA)database.In an in-ternal cohort(n=36 for RT-qPCR;n=5 for Western blot;n=30 for immunohistochemistry),BCCIP expression at both mRNA and protein levels was examined in GC tissues and paired adjacent normal tissues.Human GC cell lines AGS and HGC27 were cultured in vitro and treated with cisplatin in a dose(0,2,4,6,8 and 10 μmol/L)-and time(0,6,24 and 48 h)-dependent manner,followed by Western blot analysis of BCCIP expression.Stable BCCIP knockdown cell lines(shRNA#1 and shRNA#2 groups)were generated via lentiviral transfection,with empty vector-transfected cells serving as controls(vector group).Flow cytometry and colony formation assay were performed to evaluate the effects of BCCIP on apoptosis and colony-forming ability of GC cells treated with cisplatin.Western blot was utilized to detect the changes of BCCIP protein expression levels in the cytoplasm and nucleus of GC cells after cisplatin(2.5 and 1.0 μmol/L)treatment,as well as the effects of BCCIP on the expression of DNA damage marker γ-H2AX and apoptosis-related proteins cleaved caspase-9 and cleaved caspase-3,and the activation of checkpoint kinase 1(CHK1)after cisplatin(2.5 and 1.0 μmol/L)treatment.Immunofluorescence was conducted to observe the effect of BCCIP on γ-H2AX expression in GC cells treated with cisplatin(2.5 and 1.0 μmol/L).RESULTS:The BCCIP expression was significantly up-regulated in GC tissues compared with normal tissues(P<0.01).Cisplatin induced up-regulation of BCCIP expression in a dose-and time-depen-dent manner.Knockdown of BCCIP significantly enhanced cisplatin-induced apoptosis(P<0.01)and reduced colony-forming ability(P<0.05)of GC cells.Knockdown of BCCIP promoted the expression of γ-H2AX,but inhibited the activa-tion of CHK1 after cisplatin treatment,with increased protein levels of cleaved caspase-9 and cleaved caspase-3(P<0.01).CONCLUSION:Cisplatin promotes the expression of BCCIP in GC cells.BCCIP confers cisplatin resistance in GC cells by suppressing apoptosis through modulation of DNA damage response pathways.

Objective:To design an intelligent measurement program of detection parameters of quality control of imaging system of multi-slice spiral computed tomography (MSCT) based on MATLAB software platform,so as to achieve intelligent detection for quality control of MSCT imaging system. Methods:We designed an intelligent measurement program for the detection parameters of quality control of MSCT imaging system (referred to as the intelligent measurement program) bases on the function of graphical user interfaces (GUI) of MATLAB software. A series of algorithms such as image reading,binarization,and circular detection based on the Hough transform were employed to conduct automatic measurement and calculation for CT values (water),noise and uniformity of the parameters of MSCT quality control. The Intraclass Correlation Coefficient (ICC) was adopted to analyze the consistency of the detection results between the manual measurement method and the designed intelligent detection program. Results:The designed intelligent measurement program in this study can automatically assess the detection parameters of quality control of the MSCT imaging system,which included CT values (water),noise and uniformity. There was favorable consistency in the detection results between the manual measurement method and the intelligent measurement program (range of ICC values was from 0.881 to 0.985). Conclusion:The intelligent measurement program of detection parameters of quality control of MSCT imaging system can simplify the process of calculating detection parameters of quality control of MSCT imaging system,and provide a reliable detection tool for quality control of MSCT imaging equipment,which can effectively improve the detection efficiency of quality control.

Objective:To design an intelligent measurement program of detection parameters of quality control of imaging system of multi-slice spiral computed tomography (MSCT) based on MATLAB software platform,so as to achieve intelligent detection for quality control of MSCT imaging system. Methods:We designed an intelligent measurement program for the detection parameters of quality control of MSCT imaging system (referred to as the intelligent measurement program) bases on the function of graphical user interfaces (GUI) of MATLAB software. A series of algorithms such as image reading,binarization,and circular detection based on the Hough transform were employed to conduct automatic measurement and calculation for CT values (water),noise and uniformity of the parameters of MSCT quality control. The Intraclass Correlation Coefficient (ICC) was adopted to analyze the consistency of the detection results between the manual measurement method and the designed intelligent detection program. Results:The designed intelligent measurement program in this study can automatically assess the detection parameters of quality control of the MSCT imaging system,which included CT values (water),noise and uniformity. There was favorable consistency in the detection results between the manual measurement method and the intelligent measurement program (range of ICC values was from 0.881 to 0.985). Conclusion:The intelligent measurement program of detection parameters of quality control of MSCT imaging system can simplify the process of calculating detection parameters of quality control of MSCT imaging system,and provide a reliable detection tool for quality control of MSCT imaging equipment,which can effectively improve the detection efficiency of quality control.

Lead poisoning severely threatens human health with its cumulation and durability in the body. The analysis of lead in blood is vital for screening, diagnosis, treatment, and prognostication of lead poisoning and for indirectly monitoring the level of lead in the environment. Although the detection programs are available throughout our country, the accuracy and comparability of the results cannot meet the expectation. A variety of factors can affect the accuracy of blood lead testing. To promote the application of blood lead analysis in clinical trials and reduce the bias of results, a better reference system for blood lead analysis should be established to evaluate the accuracy of traditional methods, promote the standardization of blood lead analysis and achieve accurate blood lead testing.

Background: Serum C-peptide results from various routine methods used in China are highly variable, warranting well-performing methods to serve as an accuracy base to improve the harmonization of C-peptide measurements in China. We developed an accurate isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC–MS/MS) method for serum C-peptide measurement and explored its use in harmonization. Methods: After protein precipitation with ZnSO4 solution, C-peptide was extracted from serum samples by anion-exchange solid-phase extraction and quantified by ID-LC–MS/MS in positive ion mode. The precision and analytical recovery of the ID-LC–MS/MS method were assessed. Seventy-six serum samples were analyzed using the ID-LC–MS/MS method and six routine immunoassays. Ordinary linear regression (OLR) and Bland-Altman (BA) analyses were conducted to evaluate the relationship between the ID-LC–MS/MS method and routine immunoassays. Five serum pool samples assigned using the ID-LC–MS/MS method were used to recalibrate the routine assays. OLR and BA analyses were re-conducted after recalibration. Results: The within-run, between-run, and total precision for the ID-LC–MS/MS method at four concentrations were 1.0%–2.1%, 0.6%–1.2%, and 1.3%–2.2%, respectively. The analytical recoveries for the ID-LC–MS/MS method at three concentrations were 100.3%–100.7%, 100.4%–101.0%, and 99.6%–100.7%. The developed method and the immunoassays were strongly correlated, with all R2 >0.98. The comparability among the immunoassays was substantially improved after recalibration. Conclusions The performance of the ID-LC–MS/MS method was carefully validated, and this method can be used to improve the harmonization of serum C-peptide measurements in China.

To investigate the effectiveness and safety of diverticular peroral endoscopic myotomy (D-POEM) for mid-esophageal diverticulum. Data of consecutive patients in the prospective database with mid-esophageal diverticulum who received D-POEM in West China Hospital, Sichuan University between April 2014 to September 2019 were collected. The modified Eckardt scoring system for mid-esophageal diverticulum was used to evaluate the severity of diverticular symptoms. The effectiveness and safety of D-POEM were evaluated in terms of clinical success, technical success, complications and recurrence. A total of 7 patients with mid-esophageal diverticulum were included. Clinical and technical success was achieved in all patients with operation time of 16-70 minutes. No serious complications (2 cases with minor complications) or recurrence occurred. The follow-up time was 2-16 months. The median modified Eckardt score decreased from 3 points before operation to 0 points after operation. It is preliminarily believed that D-POEM ensures a complete septotomy between normal esophageal lumen and esophageal diverticulum. It is a safe and effective technique for mid-esophageal diverticulum. The modified Eckardt scoring system is suitable for symptom evaluation before and after treatment of mid-esophageal diverticulum.

Objective In order to test and improve the monitoring technical level and ability of radiation environmental monitoring network in Zhejiang Province, ensure the accuracy and reliability of monitoring data and information, and obtain the cosmic ray response values of instruments and equipment in this year. Methods In September 2018，an intercomparison meeting of environmental gamma radiation air absorbed dose rate within the radiation environmental monitoring network of Zhejiang province was held in Ningbo，which was organized by Zhejiang Province Radiation Environmental Monitoring Center.A total of 33 sets of instruments from 15 member units participated in the intercomparison measurements at 5 environmental measuring points, and the comparison results were evaluated by the Z score values. Results It was found that the |Z| of all measurement results were less than or equal to 2, and the evaluation results were satisfactory and acceptable. Conclusion The measured data of scintillation counters have relatively wider dispersion，and the high pressure ionization chambers have bigger response valuetocosmic ray. The measurement results of the two kinds of instruments keep a good linearity except for the measurement points of cosmic ray response.

Objective:To understand and analyze the current situation of core competence of graduate midwives in standardized training in Sichuan Province, so as to provide a reference for the training of midwives in Sichuan Province.Methods:A total of 102 midwives who participated in standardized training and graduated from July 2016 to June 2018 in Sichuan Province were investigated by using general information questionnaire (including 14 items of general information, occupational literacy and hospital conditions) and Midwives Core Competence Scale (including 54 items and 6 dimensions). Among 109 questionnaires distributed, 102 valid questionnaires were collected. SPSS 21.0 was used to analyze the results by single factor analysis and multiple linear regression analysis.Results:The average total score of the core competency scale in this study was (203.470±32.398). The scores of postpartum health care and prenatal health care were relatively high, while the score of public health care was relatively low. Multivariate regression analysis showed that whether the maternal and infant health certificates were obtained during the training period, and whether there was a training system for midwives alone and arrangements of department rotation were the influencing factors of the core competence of the graduate midwives ( P<0.05). Conclusion:The core competence of midwives in standardized training in Sichuan province is at the middle level. The standardized training of midwives is at the initial stage and lack of systematic management. Hence, it is urgent to build a unified and standardized training system.