High definition MRI rectal lymph node aided diagnostic system based on deep neural network / 中华外科杂志

Objective@#To investigate the clinical significance of high definition (HD) MRI rectal lymph node aided diagnostic system based on deep neural network.@*Methods@#The research selected 301 patients with rectal cancer who underwent pelvic HD MRI and reported pelvic lymph node metastasis from July 2016 to December 2017 in Affiliated Hospital of Qingdao University. According to the chronological order, the first 201 cases were used as learning group. The remaining 100 cases were used as verification group. There were 149 males (74.1%) and 52 females in the study group, with an average age of 58.8 years. There were 76 males (76.0%) and 24 females in the validation group, with an average age of 60.2 years. Firstly, Using deep learning technique, researchers trained the 12 060 HD MRI lymph nodes images data of learning group with convolution neural network to simulate the judgment process of radiologists, and established an artificial intelligence automatic recognition system for metastatic lymph nodes of rectal cancer. Then, 6 030 images of the validation group were clinically validated. Artificial intelligence and radiologists simultaneously diagnosed all cases of HD MRI images and made the diagnosis results of metastatic lymph node. Receiver operating characteristic (ROC) curve and area under curve (AUC) were used to compare the diagnostic level of them.@*Results@#After continuous iteration training of the learning group data, the loss function value of artificial intelligence decreased continuously, and the diagnostic error decreased continuously. Among the 6 030 images of verification group, 912 images were considered to exist metastatic lymph nodes in radiologists′ diagnosis and 987 in artificial intelligence diagnosis. There were 772 images having identical diagnostic results of lymph node location and number of metastases with the two methods. Compared with manual diagnosis, the AUC of the intelligent platform was 0.886 2, the diagnostic time of a single case was 10 s, but the average diagnostic time of doctors was 600 s.@*Conclusion@#The HD MRI lymph node automatic recognition system based on deep neural network has high accuracy and high efficiency, and has the clinical significance of auxiliary diagnosis.

Prevalence and molecular characteristics of Listeria monocytogenes in cooked products and its comparison with isolates from listeriosis cases / 医学前沿

This study aimed to investigate the prevalence and molecular characteristics of Listeria monocytogenes in cooked products in Zigong City, China. The overall occurrence of the L. monocytogenes in the ready-to-eat (RTE) shops and mutton restaurants surveyed was 16.2% (141/873). An occurrence of 13.5% was observed in RTE pork, 6.5% in RTE vegetables, and more than 24.0% in either cooked mutton or cooked haggis. Serotype 1/2b (45.4%), 1/2a (33.3%), and 1/2c (14.2%) were the predominant types. By comparing the clonal complexes (CCs) based on multilocus sequence typing (MLST) of the L. monocytogenes from cooked foods in Zigong City and 33 listeriosis cases from different districts of China, CC87, CC9, CC8, and CC3 were showed to be prevalent in cooked products and CC87 and CC3 were the first two frequent types in the 33 clinic-source strains. All CC87 stains harbored the newly reported Listeria pathogenicity island 4 (LIPI-4) gene fragment ptsA, and all CC3 strains possessed the Listeria pathogenicity island 3 (LIPI-3) gene fragment llsX. These may increase the occurrence of the strains belonging to CC87 and CC3 in listeriosis cases in China and also underline the risk of infection owing to the consumption of the cooked products from Zigong. ST619 (serotype 1/2b) harbored both llsX and ptsA, indicating a potential hypervirulent sequence type in Zigong.

Treatment of infected nonunion by external fixation / 中华创伤骨科杂志

Objective To explore the curative effects of external fixation in the treatment of infected nonunion.Methods From June 2009 to December 2016,45 patients with infected nonunion were treated by external fixation at Department of Orthopaedics,West China Hospital.They were 36 males and 9 females with an average age of 45.3 years (range,from 14 to 65 years).The sites of fracture included tibia in 31 patients,femur in 12,humerus in one,and ulna-radius in one.The median time from injury to application of external fixation was 16.8 months and the average number of previous operations was 2.3 times.After debridement,24 cases had a bone defect of 6.0 cm in length on average (range,from 3.5 to 10.4 cm).After discharge,the patients were regularly followed up at the outpatient department and any of their complications was recorded in detail.At the final follow-ups,the protocol of ASAMI (Association for the Study and Application of the Method of Ilizarov) was used to evaluate their bone and functional results.Results All the 45 patients were followed up for 16 to 106 months (average,43.9 months).One patient had to receive amputation because of uncontrollable infection and all the other 44 cases achieved bony union.The bone defects were successfully reconstructed by external bone transport in 24 patients.The time for external fixation averaged 20.5 months.According to the evaluation by ASAMI at the final follow-ups,the bone was rated as excellent in 28 patients,as good in 12,as fair in one and as poor in 3,giving an excellent to good rate of 90.9％;the function was rated as excellent in 11 patients,as good in 21,as fair in 8 and as poor in 4,giving an excellent to good rate of 72.7％.Conclusion In eradication of infection and treatment of fracture nonunion,external fixation can be used not only to avoid the infection risk due to internal fixation but also to correct a complex deformity and repair a large bone defect,allowing early weight-bearing for the patients.

Precision linear measurement using cone beam CT in dental implants：an experimental study / 中华放射学杂志

Objective The aim of this study was to investigate the accuracy and reliability of linear measurements using cone beam computed tomography(CBCT) system and to provide theoretical application of CBCT in oral implantation. Methods Ten experimental models of different toothless mandibles mixed with 10% of barium sulfate were used in this study. All these mandible models were marked with gutta-percha markers to standardize the plane of the transverse cross-sections and path of measurements. The mandible models were imaged using Mayer SS-X9010D CBCT device. Measurements were taken with DCT Viewer software and compared with measurements recorded directly in the mandible models using vernier caliper. A paired sample t-test was performed to compare difference between CBCT measurement and vernier caliper measurement. Less than 0.05 were considered statistically significant. Results The differences of vertical lines between CBCT and vernier caliper were (-0.089 5±0.220 0) mm in anterior teeth area and (-0.083 0±0.190 0) mm in posterior teeth area. The differences of vertical lines between CBCT and vernier caliper were (-0.052 0 ± 0.140 0) mm in anterior teeth area and (-0.084 7 ± 0.320 0) mm in posterior teeth area. The corresponding t values were-1.784,-1.981,-1.621 and-1.684, respectively. All the P values were greater than 0.05. There was no significant difference between CBCT measurement and vernier caliper measurement. Conclusions CBCT is auseful tool to provide good accuracy and precision of linear measurement in dental implants.

Association between SNPs in DNMT1 and noise-induced hearing loss in Chinese Han population / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the association between single nucleotide polymorphisms (SNPs) in DNA methyltransferase 1 (DNMT1) (rs12984523, rs16999593, and rs2228612) and noise-induced hearing loss (NIHL) in Chinese Han population.</p><p><b>METHODS</b>This case-control study consisted of 188 cases (case group) and 300 controls (control group) in the same working position, who were matched for age and gender. The cases had a binaural average high-frequency hearing threshold not less than 40 dB, and the controls had a binaural average high-frequency hearing threshold less than 40 dB. The genotypes at the three SNPs were determined by TaqMan probe.</p><p><b>RESULTS</b>TT genotype at DNMT1 rs2228612 is a risk factor for NIHL (adjusted OR = 1.69, 95% CI: 1.14-2.52).</p><p><b>CONCLUSION</b>The study of Chinese Han population suggested that DNMT1 rs2228612 is associated with susceptibility to NIHL.</p>

Radiofrequency ablation versus partial nephrectomy for the treatment of clinical stage 1 renal masses: a systematic review and meta-analysis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Over the past two decades, the clinical presentation of renal masses has evolved, where the rising incidence of small renal masses (SRMs) and concomitant minimal invasive treatments have led to noteworthy changes in paradigm of kidney cancer. This study was to perform a proportional meta-analysis of observational studies on perioperative complications and oncological outcomes of partial nephrectomy (PN) and radiofrequency ablation (RFA).</p><p><b>METHODS</b>The US National Library of Medicine's life science database (Medline) and the Web of Science were exhaustly searched before August 1, 2013. Clinical stage 1 SRMs that were treated with PN or RFA were included, and perioperative complications and oncological outcomes of a total of 9 565 patients were analyzed.</p><p><b>RESULTS</b>Patients who underwent RFA were significantly older (P < 0.001). In the subanalysis of stage T1 tumors, the major complication rate of PN was greater than that of RFA (laparoscopic partial nephrectomy (LPN)/robotic partial nephrectomy (RPN): 7.2%, open partial nephrectomy (OPN): 7.9%, RFA: 3.1%, both P < 0.001). Minor complications occurred more frequently after RFA (RFA: 13.8%, LPN/RPN: 7.5%, OPN: 9.5%, both P < 0.001). By multivariate analysis, the relative risks for minor complications of RFA, compared with LPN and OPN, were 1.7-fold and 1.5-fold greater (both P < 0.01), respectively. Patients treated with RFA had a greater local progression rate than those treated by PN (RFA: 4.6%, LPN/RPN: 1.2%, OPN: 1.9%, both P < 0.001). By multivariate analysis, the local tumor progression for RFA versus LPN/RPN and OPN were 4.5-fold and 3.1-fold greater, respectively (both P < 0.001).</p><p><b>CONCLUSIONS</b>The current data illustrate that both PN and RFA are viable strategies for the treatment of SRMs. Compared with PN, RFA showed a greater risk of local tumor progression but a lower major complication rate, which is considered better for poor candidates. PN is with no doubt the golden treatment for SRMs, and LPN has been widely accepted as the first option for nephron-sparing surgery by experienced urologists. RFA may be the best option for select patients with significant comorbidity.</p>

Polymorphism of methylenetetrahydrofolate reductase gene is associated with response to fluorouracil-based chemotherapy in Chinese patients with gastric cancer / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The importance of polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene for the prediction of the response to fluorouracil-based adjuvant chemotherapy in gastric cancer patients remains unclear. The aim of this study is to assess the predictive value of several polymorphisms of the MTHFR gene for clinical outcomes of gastric cancer patients treated with fluorouracil-based adjuvant chemotherapy in Chinese population.</p><p><b>METHODS</b>Three hundred and sixty-two Chinese patients with gastric cancer were treated with fluorouracil-based adjuvant chemotherapy. DNA samples were isolated from peripheral blood collected before treatment. The three single nucleotide polymorphisms (SNPs) (rs1801131, rs1801133, rs2274976) genotypes of the MTHFR gene were determined by matrixassisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).</p><p><b>RESULTS</b>The average response rate for chemotherapy was 46.7%. Homozygous genotypes rs2274976G/G (χ(2) = 22.7, P < 0.01) and rs1801131A/A (χ(2) = 14.3, P = 0.008) were over-represented in responsive patients. Carriers of the rs2274976A allele genotypes (G/A and A/A) and of the rs1801131C allele genotypes (A/C and C/C) were prevalent in nonresponsive patients. In the haplotype association analysis, there was a significant difference in global haplotype distribution between the groups (χ(2) = 20.69, P = 0.000 124).</p><p><b>CONCLUSIONS</b>These results suggest that polymorphisms of the MTHFR gene may be used as predictors of the response to fluorouracil-based chemotherapy for gastric cancer patients in Chinese population. Well-designed, comprehensive, and prospective studies on determining these polymorphisms of MTHFR gene as clinical markers for predicting the response to fluorouracil-based therapy in gastric cancer patients is warranted.</p>

Reflection on strengthening practical ability for master of public health / 中华医学教育探索杂志

Practical ability training is one of the core tasks during the education for master of public health (MPH).We got a deeper understanding of practical ability cultivation situation for MPH in our school and got a more accurate recognition of the existed problems through conducting questionnaire for three grades MPH of professional degree and related tutors.We analyzed the advantages and disadvantages of the existing mode and reflected on curriculum design,teaching method reform and practical ability training reform,etc based on the results of the questionnaire and years of experiences.

Hepatectomy for hepatic hemangioma: a study of 37 patients / 中华肝胆外科杂志

Objective To study the diagnosis,surgical indications, and results of surgical treatment for hepatic hemangioma. Methods The data of 37 patients with hepatic hemangioma treated by hepatectomy in our department from July 2005 to July 2008 were analyzed retrospectively. The diagnoses were made by ultrasound, enhanced CT and MRI. Surgical indications included: (1) diameter >5 cm, located at the left lateral section or the lower edge of the liver with symptoms. (2) diameter >10 cm or recent rapid growth. The hemangioma were located in the left liver in 10 patients, right liver in 17, caudate lobe in 3, middle hepatic lobe in 2, multiple tumors in left and right livers in 5.The preoperative liver function was grade A in all patients. Results Five patients underwent right hepatectomy, 2 underwent left hepatectomy, 10 underwent left lateral sectionectomy, 3 underwent caudate lobectomy, 5 underwent central hepatectomy, 8 underwent right anterior sectionectomy, 4 underwent combined hepatic resections and 2 underwent prophylactic exploration of the common bile duct. Pringle's maneuver was applied in 28 patients, and total hepatic vascular exclusion in 7. The occlusion time ranged from 8-36 and 10-40 minutes (average: 22.2±14.3 min and 21.6±12.1 min),respectively. 400 ml of intraoperative blood transfusion was given to 4 patients each. All operations were successfully carried out. The specimens measured 5-20 cm. There was no peri-operative death.The postoperative complications were: pleural effusion (n=4); subphrenic (n=2). Histologic diagnosis confirmed hepatic cavernous hemangioma in all patients. All patients were regularly followed-up (ranged 6 months-4 years), and no recurrence was detected. Conclusion In carefully selected patients, liver resection for hepatic hemangioma is safe and effective.