Circulating tumor DNA (ctDNA) has shown great potential in targeted therapy efficacy prediction, monitoring, high-risk population screening, differential diagnosis, minimal residual disease (MRD) monitoring, and prognosis prediction. The detection of specific gene mutations in ctDNA had been included in clinical practice guidelines for certain tumors to predict the drug efficacy and monitor resistance. A small number of approved companion diagnostic reagents have been used in clinical setting. However, the clinical validity of most ctDNA-related biomarkers it still in the research stage. Besides, the establishment and validation of laboratory-developed tests (LDT) are also problems that need to be solved urgently. Therefore, for the moment, the clinical application of ctDNA analysis is like two sides of a coin, with both opportunities and challenges.

Objective To evaluate the performance of KRAS gene mutation detection in 2014 external quality assessment ( EQA ) program and discuss the problems in clinical laboratories .Methods The sample panel of 2014 EQA program contained 5 artificial formalin-fixed, paraffin-embedded ( FFPE) samples.The participating laboratories were asked to report their results before the deadline .The scores of EQA and the rate of overall coincidence , false positive and false negative were calculated .Results The EQA program for KRAS testing was set twice a year .In 2014, 58 and 57 valid lab results were submitted respectively.About 79.31%(46/58)and 94.73%(54/57) of the laboratories were correct for all samples. The coincidence rate of positive samples were 93.53% ( 217/232 ) and 96.49% ( 165/171 ) . The coincidence rate for negative ones were 100%(58/58) and 98.25% (112/114).The false-negative ratio was 1.29%( 3/232 ) and 0%.The false-positive ratio was 4.14% ( 12/290 ) and 3.15% ( 9/285 ) . Conclusions The results of 2014 EQA for KRAS gene mutation testing suggested that the performance of laboratories had been improved significantly , however , the false-negative and false-positive results had always been the major problems affecting the accuracy of KRAS mutations testing .Laboratories needed to standardize the testing process and manufacturers should optimize the reagents and the way of interpretation , to guarantee the performance of KRAS gene mutation detection .

Objective To study the optimum flavonoids extraction process of Elaeagnusangustifolia L. with ethanol. Methods The best condition of extraction process of flavonoids was investigated by orthogonal design. Results The ratio of extraction on this condition was 2.295 mg/g. Conclusion The optimum technological conditions attained by theorthogonal experiment was as follows:concentration of ethanol 70%, extraction temperature 45 ℃, extraction time 30 min and the ratio of Elaeagnusangustifolia L. to extractant 1∶16.

Objective To evaluate the clinical application and significance of enzyme-linked immunosorbent assay(ELISA)for serologically diagnosing bullous dermatosis.Methods Serum Dsg1,Dsg3 and BP180 expressions were detected in 34 cases of pem-phigus,32 cases of bullous pemphigoid and 33 cases of non-bullous dermatosis by ELISA.Results The sensitivity and specificity of ELISA for detecting the bullous dermatosis antibody were 87.88% and 93.94% respectively.Conclusion The ELISA method has the diagnostic value on bullous dermatosis and the important significance in the disease classification.

Objective To establish a way to measure the injury severity of articular surface due to posterior malleolus fracture and investigate its clinical significance based on three-dimensional reconstruction technique.Methods Between May 2009 and March 2014,138 cases of peri-ankle injury combined with posterior malleolus fracture were treated.Lateral radiographs were reviewed to measure the ratio of posterior fragment area to distal tibial plafond area using the common method.Three-dimensional CT images were examined to measure ratio of the area of injury using the three-dimensional measuring method.Statistical comparison was made using the t-test and intraclass correlation coefficient (ICC).Results Measurement failed on 33 lateral radiographs and 13 three-dimensional CT images.Six cases cannot be measured by both imaging technology,so results of 98 cases were compared.Ratio of posterior fragment area to tibial plafond area was (16.2 ± 7.2) ％ measured by radiographs and was (29.6 ±10.1) ％ by three-dimensional CT scans (P ＜ 0.05).Three-dimensional CT measurements showed higher intra and inter-observer agreement (ICC of 0.973 to 0.942) than that in radiographic measurements (ICC of 0.875 to 0.860).Conclusion Three-dimension CT assessment of the extent of injury to articular surface because of posterior malleolus fracture is reliable and reproducible,but radiographic assessment may underestimate the injury and influence the choice of surgical indications.

Objective To investigate the effect of sustentaculum tali screw placement on outcomes following open reduction and internal fixation (ORIF) of intraarticular calcaneal fractures.Methods A retrospective analysis was made on 139 patients with intraarticular calcaneal fractures treated by ORIF from April 2008 to January 2012.According to Sanders classification,there were 9 patients with type Ⅱ fractures,87 with type Ⅲ fractures and 43 with type Ⅳ fractures.Fracture reduction followed by placement of calcaneal anatomic plate or anatomic locking plate was performed via calcaneal lateral L-shape incision.All the patients received X-rays and CT scans within postoperative 2 weeks.Placement of screws in sustentaculum tail was detected by CT volume rendering to visualize implants combined with multiplanar reconstruction imaging (MPR).Patients were divided into accurate fixation group (Group A,n =28),marginal fixation group (Group B,n =58),and non-fixation group (Group C,n =53) based on radiological results.Intra-and peri-operative parameters,time to partial weight-bearing,time to full weight-bearing,fracture healing time,and clinical outcome were compared among groups.Functional outcome was assessed using American Orthopedic Foot and Ankle Society (AOFAS) Ankle Hindfoot Scale.Results Postoperative X-rays indicated accurate fixation of sustentaculum tail in 64 patients,marginal fixation in 22,and non-fixation in 53,but CT images manifested accurate fixation in 28 patients,marginal fixation in 58,and non-fixation in 53.Group A had operation duration of (93 ±11) min and intraoperative blood loss of (252 ± 27) ml,longer or higher than those in Group B [(85 ±8) min,(194±16) ml] and Group C [(57±6) min,(136 ±13) ml] (P＜O.05).There was no significant difference in mean hospital stay among the three groups (P ＞ 0.05).Ninety-two patients were followed-up for 12-38 months (mean 18.5 months) and 85 patients completed foot and ankle exercise as planned.Moreover,no significant differences were observed among groups concerning time to partial and full weight-bearing,fracture healing time and AOFAS score at the final follow-up (P ＞ 0.05).Conclusion Sustentaculum tali screw placement has no apparent effect on the short-term outcome of surgical treatment for calcaneal fractures.

ThemagneticFe3O4nanoparticlesweresynthesizedbyco-precipitationmethod,andthenmagnetic Fe3 O4@Au nanoparticle was synthesized to improve the affinity of particle surface. L-Cys-GA3 was grafted on the surface of gold clad by self-assembly method, and then dropped it on glassy carbon electrode, for further manufacture of MIP/Fe3 O4@Au by using electropolymerzation L-Cys. The surface morphology and particle size distribution of Fe3 O4@Au were studied by TEM. The structure and composition of gibberellins A3, MIP and nMIP were studied by IR. The test system was optimized, and the results showed that when the cycles of electropolymerization was 30, acetic acid:methanol (1:8, V/V) was chosen as eluent, elution time was optimized for 5 min and rebinding time for 7 min, the sensor got a high stability and good recognition ability for gibberellins A3 . The concentration of gibberellins A3 in the range of 1 . 0 × 10-11-1 . 0 × 10-8 mol/L had a relationship with the oxidation peak current of probe, with the detection limit of 2. 57×10-12 mol/L. The sensor was successfully used for the determination of GA3 in beer sample.

Objective To approach the significance of procalcitonin(PCT)in judgment of the degree of severity in patients with acute pancreatitis(AP). Methods A prospective method was conducted in the study. Ninety-eight patients with AP admitted from April 2013 to December 2013 in the First Affiliated Hospital of Zhengzhou University were enrolled. They were divided into mild AP(MAP,48 cases)and severe AP(SAP,50 cases)groups, biliary AP(58 cases)and non biliary AP(40 cases)groups,and biliary SAP and biliary MAP groups,non biliary SAP and non biliary MAP groups. The venous blood levels of PCT on the first day and second day after admission were assayed for all the patients,and the correlations between PCT levels on the two time points respectively and each of the following items were calculated:Ranson score,acute physiology and chronic health evaluation Ⅱ(APACHE Ⅱ)score,CT grade,number of organ dysfunction,intensive care unit(ICU)time of stay and total time of hospitalization. Results On the second day after admission,the PCT levels in groups different in etiology and groups different in severity were all elevated and higher than those on the first day,the level in SAP group being significantly higher than that of MAP group〔3.723(2.538,9.023)vs. 0.282(0.166,1.348),P<0.01〕,the level in biliary AP group being higher than that in non biliary AP group〔2.567(1.483,8.412)vs. 2.391(1.262,7.453),P>0.05〕,the level in biliary SAP group being higher than that in biliary MAP group〔4.023(3.273,10.015)vs. 0.305 (0.244,1.413),P<0.01〕,and the level in non biliary SAP group being higher than that in non biliary MAP group〔3.624(2.454,8.993)vs. 0.256(0.144,1.137),P<0.01〕. The correlations between PCT levels on the first day and second day after admission and each of the following items were respectively as follows:the correlations with Ranson score〔relative risk (RR1)=0.643,P1=0.001,95% confidence interval(95%CI1):0.435-1.596;RR2=0.762, P2=0.001,95%CI2:0.692-1.541〕,APACHE Ⅱ score(RR1=0.543,P1=0.009,95%CI1:0.842-1.512;RR2=0.672,P2=0.001,95%CI2:0.747-1.234)and CT grade(RR1=0.231,P1=0.048,95%CI1:0.596-1.412;RR2=0.256,P2=0.032,95%CI2:0.702-1.324)were all positive;the higher the number of organ dysfunction,the higher the level of PCT(RR1=0.321,P1=0.023,95%CI1:0.763-2.588;RR2=0.389,P1=0.020,95%CI2:0.683-1.742);the level of PCT had relatively favorable correlation with ICU time of stay(RR1=0.423,P1=0.019,95%CI1:0.779-1.459;RR2=0.453,P2=0.010,95%CI2:0.684-1.853),but there was no correlation between the level and the total time of hospitalization(RR1=0.004,P1=0.067,95%CI1:0.864-2.071;RR2=0.009,P2=0.078,95%CI2:0.645-1.376). Conclusion The level of PCT can be used in judgment of the degree of severity of the patients with AP,not only it can be applied in patients biliary in origin,but also can be used in patients non biliary in origin.

Objective:To analyze the characteristics of adults (non-pregnant women) infected with Listeria monocytogenes and to provide evidence for diagnosis and treatment of this disease. Methods:Patients admitted in West China Hospital of Sichuan University between January 2008 and April 2020 with Listeriadisease were enrolled in this study. The clinical data of patients including age, symptoms, underlying diseases and prognosis, as well as the laboratory results of WBC, neutrophil ratio (N%), procalcitonin (PCT), interleukin-6 (IL-6) and C-reactive protein (CRP), were obtained for analyzing the clinical infection and prognosis characteristics of the patients. Results:A total of 57 patients were included, patients were 18-83 (52.8±15.9) years old, percent of over 60 years old patients accounted for 35.09% (20/57). The incidence rate in summer season was the highest (45.61%, 26/57). There were 48 cases with comorbidities, sepsis occurred in 31 cases and meningitis in 18 cases. The time of diagnosis of Listeriosis was (6.1±2.9) days. After diagnosis, the target therapy was applied: such as carbapenem (26.32%, 15/57) and penicillins (22.81%, 13/57). The levels of WBC (6.77 [2.99, 9.54]×10 9/L vs 10.23 [6.71, 16.55]×10 9/L), NLR (3.07 [1.66, 8.16] vs 11.26 [5.66, 20.08]) and CRP (40.7 [16.9, 91.9] g/L vs 92.8 [59.9, 142.7] g/L) were significantly lower after treatment than those before treatment in 47 hospitalized patients (all P<0.05). Thirty-eight patients were treated according to the guidelines, 33 cases improved, 2 cases had poor prognosis and 2 cases died. Conclusion:The main risk factors of Listeria monocytogenes infection in adults (non-pregnant women) are underlying diseases, especially autoimmune diseases and pulmonary infections. Penicillins can be used as the first choice for empirical therapy. Carbapenems and erythromycin serve as the combination medications during the full course of treatment.

Neuroendocrine tumors (NETs) is a rare and heterogeneous group of tumors with widely varying morphologies and behaviors. Due to their rarity and heterogeneity, progress in improving its treatment has been slow. Pancreatic neuroendocrine tumors (pNETs) is a subset of NETs, previously known as islet cell tumors, occupies 3% of the primary pancreatic tumors with the annual incidence rate of (1-2)/100 000. In recent years, it is very necessary to improve the diagnosis and treatment of pNETs.