Objective To evaluate the accuracy of dose-length product (DLP) values in CT dose reports by comparing them with the DLP values measured using a pencil-type ionization chamber. Methods Experiments were conducted using four CT scanners with different detector row numbers from two manufacturers (A and B), along with a head phantom and a pencil-type ionization chamber. Other scanning parameters were fixed, while pairwise combinations of kV and mAs were tested. The DLP values were measured under various scanning conditions using the pencil-type ionization chamber (DLP_measured) and the corresponding DLP values in CT dose reports were recorded (DLP_reported). All data were subjected to statistical analysis. Results Differences were observed between DLP_reported and DLP_measured values. The smallest mean absolute value of ΔDLP was approximately 2.526 mGy·cm observed on the 40-row CT scanner of manufacturer A. There was a difference between the ΔDLPs of the four CT scanners. Both DLP_reported and DLP_measured exhibited a linear relationship with mAs. Conclusion The percentage errors between DLP_reported and DLP_measured values for all four CT scanners were within the national standard tolerance of 15%. DLP values in CT dose reports can serve as a reference for assessing patient radiation dose during scanning. However, for radiation dose-related research, data measured using dosimetric instruments such as pencil-type ionization chamber are recommended.

Since December 2019, unexplained pneumonia has appeared in Wuhan City, Hubei Province, and a new type of coronavirus infection was confirmed as COVID-19. COVID-19 spread rapidly nationwide and abroad. The COVID-19 has brought huge impacts to all the people and walks of life, especially to the medical and health systems. It has also brought great challenges to the treatment of patients with cancer. Esophageal cancer is a common malignant tumor in China and most of the patients are in the middle and advanced stage when diagnosed, with immunosuppressive and poor prognosis. The selection of surgical procedures and perioperative managements of esophageal cancer require all thoracic surgeons work together to figure out a reasonable system of surgical treatment and emergency response.

AIM: To observe the expression change of growth and differentiation factor 10 ( GDF10 ) in the spinal cord of the rats with neuropathic pain .METHODS:Male SD rats (n=60) were used.The neuropathic pain was induced by ligation of left L 5 spinal nerves of the animals .The paw withdrawal threshold was detected 1 d before surgery , and 0 d, 1 d, 3 d, 10 d and 21 d after surgery.The changes of GDF10 in the dorsal horn of L5 spinal cord were detected by immunofluorescence staining and Western blot .RESULTS:The paw withdrawal threshold of the rats with spinal nerve ligation was decreased from 1 d after surgery until 3 d with obvious difference compared with the na ve rats ( P<0.05 ) , continuously decreased until 10 d, and then stabilized at 21 d.The GDF10 was located in the cytoplasm of the neurons in the dorsal horn of L5 spinal cord detected by immunofluorescence staining .The expression of GDF10 in L5 dorsal horn de-tected by immunofluorescence staining was reduced after surgery , significantly decreased from 10 d ( P<0.05) until more than 21 d after surgery in spinal nerve ligation group compared with na ve group.GDF10 in L5 spinal cord detected at 10 d after surgery by Western blot was significantly down-regulated in spinal nerve ligation group compared with na ve group (P<0.05).CONCLUSION:Spinal nerve ligation induces the decrease in GDF 10 expression in spinal dorsal horn .The down-regulation of GDF10 may contribute to the regulation of hyperpathia caused by mechanical stimulation after the injury of spinal nerve .

Objective To construct sigF deletion mutant of Bacillus anthracis and the complementary strain of sigF deletion mutant in order to analyze the effect of losing sigF on formation of spores.Methods The spectinomycinadenyltransferase gene(spc) was inserted to replace sigF of B.anthracis by homologous recombination.A plasmid which contained sigF and sigF promotor was constructed and then transferred to the mutant to get a complementary strain of sigF deletion mutant.The characters of the mutant were analyzed by measuring growth curves, the ability of carbohydrate metabolism was compared, and spore formation was observed under a microscope.Results The sigF deletion strain A16D2△sigF was constructed from A16D2,which had a similar growth rate to the wild type A16D2 in logarithmic phase, but was not significantly different from the initial strain in the ability to use carbohydrates,although unable to form spores.The strain was found to maintain the state of asymmetric division by microfluidics experiment.Conclusion It is showed by this study that sigF is the essential gene of B.anthracis for spore formation, but not essential for vegetative growth.

Objective To investigate the application value and feasibility of enhanced recovery after surgery (ERAS) in thoracoscopic and laparoscopic esophagectomy for esophageal cancer.Methods The clinical data of 304 patients with esophageal cancer who were admitted to the Affiliated Cancer Hospital of Zhengzhou University from December 2013 and July 2014 were retrospectively analyzed.All the patients underwent esophagogastric partial resection, esophagogastric cervical anastomosis and 2-field lymph node dissection under general anesthesia.The management of 195 patients guided by ERAS were allocated to the ERAS group and 109 patients receiving perioperative traditional treatments were allocated to the control group.Observing indicators included : (1) enteral and parenteral nutritional support treatments;(2) nutrient indexs: levels of serum albumin (Alb) and prealbumin;(3) the recovery of gastrointestinal function: time to anal exsufflation and defecation;(4) postoperative complications and the grading according to Clavien standard;(5) duration of postoperative hospital stay and treatment expenses;(6) risk factors affecting postoperative complications by multivariate analysis;(7) independent risk factors affecting occurrence rate of postoperative complications by univariate analysis.Measurement data with normal distribution were presented as (x) ± s and analyzed using the t test.Nonnormal distribution data were analyzed by the Wilcoxon rank sum test.Comparison of repeated data was analyzed by the repeated measures ANOVA.Categorical variables were analyzed using the chi-square test or Fisher's exact probability.The multiple linear regression analysis and Logistic regression were used to measure the multivariate analysis of continuous variables and binary variable, respectively.Results (1) During the enteral and parenteral nutritional support treatments, 11 patients with surgery-related complications in the ERAS group didn't receive oral intake at postoperative day 1,26 proceeded the intravenous rehydration at postoperative day 4 due to calorie intake less than 80％ of calorie requirement, and enteral nutritional support treatment was well-tolerated in the control group.(2) Comparison of nutrient indexs : the levels of serum Alb and prealbumin at postoperative day 1, 3 and 5 were (37.2±3.9)g/L, (39.1 ±3.5)g/L, (38.5 ±3.0)g/L and (0.20 ±0.06)g/L, (0.13 ±0.04)g/L, (0.13 ±0.04)g/L in the ERAS group, (37.7 ±2.8)g/L, (39.0 ±3.6)g/L, (38.4 ±3.8)g/L and (0.18 ± 0.06) g/L, (0.13 ± 0.04) g/L, (0.13 ± 0.04) g/L in the control group, respectively, showing no significant difference in the postoperative changing trends between the 2 groups (F =0.357, 0.453, P ＞ 0.05).(3) The recovery of gastrointestinal function : time to first anal exsufflation and first defecation were (2.1 ± 0.8) days and (3.4 ± 1.2) days in the ERAS group, (3.2 ± 0.9) days and (5.5 ± 1.5) days in the control group, respectively,showing significant differences between the 2 groups (t =-10.505,-13.174, P ＜0.05).(4) There was no death in the perioperative period.The overall incidences of postoperative complications and number of patients with severe complications were 26.15％ (51/195) and 8 in the ERAS group, 30.28％ (33/109) and 8 in the control group, with no significant difference between the 2 groups (x2=0.594, 1.469, P ＞ 0.05).Eight and 10 patients in the ERAS and control groups underwent gastrointestinal decompression, 6 and 8 patients in the ERAS and control groups underwent retreatment in the intensive care unit (ICU), 3 and 2 patients in the ERAS and control groups were readmitted to the hospital at 3 weeks after discharge, with no significant difference in the above indexes (x2=0.185, 2.892, P ＞0.05).(5)The duration of postoperative hospital stay and treatment expenses were (6.8 ±2.4)days and (25 088 ±10 336)yuan in the ERAS group, (11.1 ±3.4)days and (38 819± 14 854)yuan in the control group, showing significant differences between the 2 groups (t =-12.782,-9.452,P ＜ 0.05).(6) The age, gender, preoperative weight loss ＞ 10％, tumor staging, tumor differentiation,neoadjuvant chemotherapy and time of food intake were risk factors affecting incidence of postoperative complication in patients with esophageal cancer by the univariate analysis (x2=2.484, 2.333, 0.061, 8.553,2.459, 0.163, 3.462, P ＜ 0.05).(7) The age, preoperative weight loss ＞ 10％, tumor staging and neoadjuvant chemotherapy were independent risk factors affecting incidence of postoperative complication in patients with esophageal cancer by the multivariate analysis (OR =0.365, 10.761,0.290, 8.140, 95％ confidence interval :0.198-0.671, 4.122-28.095, 0.130-0.645, 3.946-16.791, P ＜0.05), but time of food intake was not an independent risk factor (OR =0.540, 95％ CI: 0.280-1.041, P ＞ 0.05).Conclusions ERAS in the esophageal minimally invasive surgery for esophageal cancer is safe and feasible, with the advantages of shorter recovery time of gastrointestinal function and duration of hospital stay, lower treatment expenses and a better application value compared with traditional treatment.

OBJECTIVETo investigate the feasibility of no nasogastric intubation and early oral feeding at will after thoracolaparoscopic esophagectomy for patients with esophageal cancer.

METHODSBetween January 2013 and January 2014, the feasibility of no nasogastric intubation and early oral feeding at postoperative day(POD) 1 after thoracolaparoscopic esophagectomy was prospectively investigated in 156 patients (trial group) with esophageal cancer in the Henan Cancer Hospital. One hundred and sixty patients previously managed in the same unit who were treated routinely after thoracolaparoscopic esophagectomy were served as control group.

RESULTSOf 156 patients of trial group, 6(3.8%) patients could not take food early as planned because of postoperative complications. The overall complication rate in trial group was 19.2%(30/156), which was 25.0%(30/160) in control group (P=0.217). The anastomotic leakage in trial group and control group was 2.6%(4/156) and 4.3%(7/160) respectively (P=0.380). Compared with control group, time to first flatus [(2.1±0.9) d vs. (3.3±1.1) d, P<0.001], bowel movement [(4.4±1.3) d vs. (6.6±1.0) d, P<0.001] and postoperative hospital stay [(8.3±3.2) d vs. (10.4±3.6) d, P<0.001] were significantly shorter in trial group.

CONCLUSIONSNo nasogastric intubation and early oral feeding postoperatively in patients with thoracolaparoscopic esophagectomy is feasible and safe. This management can shorten postoperative hospital stay and fasten postoperative bowel function recovery.

Eating ; Esophageal Neoplasms ; surgery ; Esophagectomy ; Fasting ; Feasibility Studies ; Humans ; Intubation, Gastrointestinal ; Postoperative Complications ; Postoperative Period

Objective To explore the function of gene phoN1 in Shigella flexneri.Method Using the λ-Red recombi-nant system, phoN1was knocked out from S.flexneri 2a strain 301.Comparative proteomics was performed to analyze the differences between mutant and wild-type strains in protein expression profiles .Sereny tests and competitive infection assays were carried out to compare the virulence of mutant and wild-type strains .Results The deletion mutant of phoN1 was suc-cessfully constructed .No significant difference between the two strains was found in the comparative proteomics analyses . The function of gene phoN1 might be unrelated to the invasion ability of S.flexneri according to the results of Sereny tests and competitive infection assays .Conclusion Gene phoN1 might be of no use for the in vitro survival and host cell invasion of S.flexneri.

Objective To compare the separation effects of protein samples extracted by two different methods with two -dimensional gel electrophoresis (2-DE) .Methods Ultrasonic disruption and glass-beads grounding were used to prepare protein samples of Gram-negative bacteria , Gram-positive bacteria and animal tissues .The actual results of the two sample preparation methods were compared by 2-DE.Results The 2-DE maps of samples extracted by the two methods were obtained.Conclusion The 2-DE maps of glass-beads grounding samples are better than those of ultrasonic disruption thanks to their lower backgrounds , which are beneficial for further image analyses .

Objective: To investigate the incidence of coutrast media iodixanol-induced delayed adverse reaction with the risk factors in general clinical practice.
Methods: A total of 20,185 patients with contrast iodixanol were recruited from 95 medical centers in China. The risk factors for adverse drug reaction as hypertension, asthma, previous contrast reaction were assessed;the administrative processes as route, injection manner, lfow rate of injection, prior heating of iodixanol were monitored and the demographic information was documented. The immediate adverse reaction within 1 hour of media administration and the delayed adverse reaction from 1 hour to 7 days after administration were recorded. The risk factors for iodixanol-induced delayed adverse reaction were studied by singlevariate and multivariate logistic regression analysis.
Results: The overall iodixanol-induced adverse reaction rate was 1.52%, of which the immediate reaction was 0.58%and delayed reaction was 0.97%. The major delayed reaction was mild and it mostly happened in skin (0.68%) including rash, pruritus and urticaria. Multivariate logistic regression analysis revealed that male gender (OR=0.71, P=0.036), age (OR=0.82, P=0.001), route of administration (OR=0.21, P<0.001), prior heating of iodixanol (OR=1.44, P=0.036), lfow rate of injection (OR=1.28, P=0.001) and previous contrast reaction (OR=16.04, P<0.001) were the independent risk factors for delayed adverse reactions.