Objective: To obtain purified and functional CDNF-his recombinant protein and prepare its polyclonal antibodies.Methods:Preparation of recombinant CDNF-his was carried out in HEK 293 T cells with pVR1012-CDNF-his successfully constructed transfected into them.Then,the recombinant protein was purified by Ni-NTA immunoaffinity chromatography.The purity was analyzed by SDS-PAGE and the protein′s identity was tested by Western blot.MTT was used to verify the biological function of the protein purified.New Zealand white rabbits were immunized with purified CDNF-his protein for preparation of polyclonal antibodies.Results:pVR1012-CDNF-his expressed successfully in HEK 293 T cells.The purity of protein was up to more than 90%after purification.MTT showed that CDNF-his was able to protect PC 12 cells from damage by 6-OHDA.The polyclonal antibody was detected at the end of animal immunizing process.Conclusion: A method to express and purify protein using HEK 293T cell and following Ni-NTA immunoaffinity chromatography has been built.CDNF-his with biological activity is obtained based that.Finally, polyclonal antibodies of CDNF were generated successfully.

Objective To evaluate the security of catheter-based renal denervation by two dimensional speckle tracking imaging.Methods 20 dogs was ablated,whose indicies of heart and blood pressure were detected 6 weeks later.Standard 2D images were acquired in the 2-,3-and 4-apical views as well as the parasternal short-axis views at the level of the mitral valve and papillary muscles.The time to peak-systolic strain of each segment in the level of the mitral valve and papillary muscles,the standard deviation of the time to peak-systolic strain,the peak strain of the longitudinal 12-segment were recorded.Parameters were compared among the before and after ablation.Results Compared with before ablation of renal sympathetic nerve,the systolic pressure and diastolic pressure didn't reduced significantly after the ablation of renal sympathetic nerve (P ＞ 0.05),while there were no significant difference in the peak strain of the longitudinal 12-segment,the dyssychrony parameters and the size of the heart cavity before and after ablation(P ＞0.05).Conclusions The pressure had no change after the ablation of renal sympathetic nerve while without harmful effect on the the size of the heart cavity,the function of the myocardial contraction and the dyssychrony parameters.The ablation of renal sympathetic nerve can' t lower the normal blood pressure and be safe for heart at the same time.

Objective To evaluate the synchrony of heart after catheter-based renal denervation by two dimensional speckle tracking imaging.Methods Each renal sympathetic nerve of 20 dogs were ablated,and the index of heart and blood pressure were detected 6 weeks later.Standard 2D images were acquired in the 2-,3-and 4-apical views.The times from QRS onset to peak-systolic strain rate and to peak-diastolic strain rate were measured for the longitudinal 16-segments in Qlab software,and the standard deviation were calculated.The time to peak longitudinal strain rate and time to peak contraction strain rate of left atrium were measured for each segment contained septal,latera,anterior and posterior in the level of the basal segments,middle sections and apical in Qlab software,and the standard deviation were calculated.Parameters were compared among the before and after of the ablation.Results The systolic pressure and diastolic pressure had no changes after the ablation of renal sympathetic nerve (P ＞ 0.05).The R-R showed a increasing trend,but no significant differences(P ＞0.05).The peak time of LV systolic and diastolic strain rate had a extended trendency too,but no differences(P ＞0.05),and standard deviations of the peak times had no significant differences(P ＞0.05).The peak time of LA longitudinal strain rate and contraction strain rate had a extended trendency,but no obvious change (P ＞0.05),and the standard deviations of the peak times had no significant differences (P ＞0.05).The size of the heart cavity had no differences(P ＞0.05).Conclusions The systolic pressure and diastolic pressure have no changes after the ablation of renal sympathetic nerve,and the synchrony parameters of LV and LA have no significant differences,demonstrate that the synchrony of heart is not affected by the renal sympathetic denervation.

Objective To evaluate the application value of inhibitor enhanced modified carbapenemase inactivation method (imCIM) in the detection of class B carbapenemase.The differences between imCIM and EDTA disc potentiation test (EDPT) were comparatively analyzed.Methods A total of 181 strains of carbapenem insensitive strains were collected,among which there were 44 strains of Klebsiella pneumoniae,44 strains of Escherichia coli,43 strains of Acinetobacter baumannii and 50 strains of Pseudomonas aeruginosa.The 83 strains of carbapenem-sensitive strains were composed of 25 strains of Klebsiella pneumoniae,16 strains of Escherichia coli,25 strains of Acinetobacter baumannii and 17 strains of Pseudomonas aeruginosa.The class B carbapenemase in the 264 strains of pathogenic bacteria was screened by imCIM and EDPT,and PCR results were used as gold standard.The statistical analysis wasperformed with consistency check,related-sample Wilcoxon signed rank sum test,independent samples Kruskal-Wallis H test and ROC curve.Results Among the 181 strains of carbapenem insensitive strains,PCR results of 144 strains were positive for drug resistance gene.The samples of class A,B and D of carbapenemase were 39,77 and 28 strains respectively.The results of imCIM showed that 70 strains were positive,and the other 111 strains were negative.The imCIM results of 166 strains were consistent with those of PCR.The results of EDPT showed that 72 strains were positive,and the other 109 strains were negative.The EDPT results of 134 strains were consistent with those of PCR.The results of PCR,EDPT and imCIM of 83 carbapenem sensitive strains were negative.The sensitivity and specificity of imCIM were 85.71％ (66/77) and 97.86％ (183/187),and the value of Kappa was 0.859.The sensitivity and specificity of EDPT were 66.23 ％ (51/77) and 88.77 ％ (166/187),and the value of Kappa was 0.561.The difference of inhibition zone of imCIM (AdimCIM) was different from EDPT(AdEDPr) and the difference was statistically significant (Z =-6.941,P ＜ 0.05).In the imCIM detection,the AdimciM level of class B carbapenemase showed different population distribution position from class A and D carbapenemase with the statistically significant difference (x2 =108.887,P ＜ 0.05).The areas under the ROC curve of imCIM and EDPTwere 0.988 (95％CI:0.977 to0.999) and0.936 (95％CI:0.909 to0.963),respectively.Conclusion imCIM should be accurate,efficient and convenient for screening of carbapenem phenotype for its high sensitivity and specificity,and suitable for epidemiological monitoring.

Objective To investigate the feasibility of modified rapid Carba NP test for the detection of carbapenemase,and analyze the differences between the modified method and Carba NP test.Methods A total of 264 strains of gram-negative bacillus,including 164 carbapenem-resistant strains and 100 sensitive strains,were collected,and their carbapenemase were detected by Carba NP test and the modified rapid Carba NP test,respectively.The differences between the two tests were evaluated based on PCR as a reference.Results Among 164 carbapenem-resistant strains,carbapenemase gene was detected in 144 strains by PCR.The carbapenemase gene was negative in 100 sensitive strains.Among 164 carbapenem-resistant strains,135 were positive for the Carba NP test,while 130 for the modified rapid Carba NP test.One hundred of sensitive strains were negative for the two Carba NP tests.Compared with the results of PCR,the sensitivity,specificity and Kappa value of the Carba NP test were 91.7％ (132/144),97.5％ (117/120) and 0.886,respectively,while those of the modified rapid Carba NP test were 89.6％ (129/144),99.2％ (119/120) and 0.879,respectively.There was no significant difference in the positive rates between Carba NP test and the modified rapid Carba NP test (x2 =1.45,P ＞ 0.05).Conclusion The modified rapid Carba NP test which has high consistency with the PCR method,is faster and cheaper than the Carba NP test,and may be applied to epidemiologic survey and the early monitoring of nosocomial infections.

Objective To investigate the value of "one-stop" scanning of coronary and head and neck CTA in patients with normal body mass index (18 kg/m2 ≤ BMI ≤ 25 kg/m2) using low tube voltage (80 kVp).Methods In a retrospective analysis 80 patients with normal body mass index who had completed "one-stop" scanning of coronary and head and neck CTA were divided into A and B groups according to different scanning method,and 40 consecutive cases were selected in each group.Scanning parameters of group A and group B were tube voltage 80 kV,coronary CTA tube current 550 mA,head and neck CTA tube current 500 mA,and tube voltage 100 kV,coronary CTA tube current 450 mA,head and neck CTA tube current 400 mA separately.Subjective evaluation and objective evaluation were performed on the image quality of the two groups.CT values of coronary artery and head and neck CTA trunk branch vessel,contrast-to-noise ratio (CNR),image noise (SD) and effective dose between the two groups were compared.Results The image quality of both groups met the diagnostic requirements,and there was no statistically significant difference in subjective scores between two groups (P＞0.05).The CT values of coronary arteries,the main branches of the head and neck (the common carotid artery,the internal carotid artery) and SD of head and neck CTA were significantly different between two groups (t=4.737,6.552,3.359,2.165,2.685,4.617,P＜0.05).There was no statistically significant difference in SD of coronary CTA,CT values and CNR between head and neck vessels (middle cerebral artery) in group A and group B (P＞0.05).The effective dose of coronary CTA in group A (1.16±0.20) mSy was reduced by 51.1％ than that in group B (2.37±0.77) mSv.The effective dose of head and neck CTA in group A (0.37±0.03) mSv was reduced by 47.9％ than that in group B (0.71 ± 0.17) mSv.Conclusions The image quality with subjective evaluation met the diagnostic requirements when using a low-tube voltage for "one-stop"scanning of coronary and head and neck CTA.The CNR values were basically consistent with the conventional scanning method,and the patient effective dose was reduced by about 50％.

Objective:To evaluate the feasibility and accuracy of a multi-dimensional peripheral quick contrast sensitivity function (pqCSF) measurement established based on Bayesian probability estimation algorithm.Methods:A cross-sectional study was conducted.Nineteen eyes of 12 healthy emmetropic subjects in Zhongshan Ophthalmic Center of Sun Yat-sen University from September 2017 to March 2018 were included, with an average age of (22.92±2.91) years.The average spherical power and cylindrical power were (-0.34±0.52)D and (-0.30±0.42)D, respectively, and the average uncorrected vision acuity was≥1.0.Based on the Bayesian probability algorithm, the peak contrast sensitivity γ max, the peak spatial frequency ? max, the bandwidth β and the low contrast intercept δ were used to quickly describe the contrast sensitivity function (CSF) curve of the full spatial frequency through multi-dimensional pqCSF method.The 16 peripheral visual field positions of all subjects were tested at 6°, 12°, 18° and 24° eccentricity of the superior, inferior, the temporal and nasal visual field by the pqCSF method, but the 18° eccentricity of temporal field, which was near the physiological blind spot, was excluded.The area under Log CSF (AULCSF) of different peripheral visual fields and the Log CSF of 19 spatial frequencies (distributed at equal intervals in logarithmic units) were compared.This study followed the Declaration of Helsinki, and the study protocol was approved by an Ethics Committee of Zhongshan Ophthalmic Center of Sun Yat-sen University (No.2018KYPJ017). Written informed consent was obtained from each subject prior to any examination. Results:With the increase of eccentricity in different visual fields, the AULCSF decreased gradually, and there were significant differences in AULCSF between different eccentricities (all at P<0.05). The AULCSF of the nasal and temporal visual field at 6°, 12° and 24° eccentricity was significantly larger than that of the superior and inferior visual field (all at P<0.05). As the distance from the fovea was increased, the pqCSF, the AULCSF, and the high-frequency cutoff were all decreased, and the standard deviation of AULCSF was increased gradually. Conclusions:The pqCSF method can depict a relatively complete peripheral CSF curve of a wide peripheral visual field, and reflect the function quality of the peripheral vision comprehensively and accurately.

Objective:To investigate the current application of colonoscopy at hospitals in China.Methods:From November 2019 to January 2020, an online questionnaire survey was conducted among gastroenterologists and colonoscopists in hospitals of different levels. The contents of questionnaire survey included basic information of colonoscopy at the respondent′s hospital, protocols and patient education of bowel preparation, implementation of colonoscopy quality control, and colonoscopists′ understanding of polypectomy techniques and post-polypectomy follow-up.Results:A total of 236 valid questionnaires were collected, involving 187 hospitals, and 143 (76.5%) had an annual operation capacity of more than 5 000 cases. In terms of bowel preparation, split-dosed polyethylene glycol electrolyte powder (PEG) was the most commonly used (60.4%, 113/187) and the most common volume of PEG was 3 L (67.4%, 126/187). Verbal (90.9%, 170/187) and written (79.7%, 149/187) instructions were given more often than other methods for patient education of bowel preparation. Antifoaming agent was routinely used in 124 (66.3%) hospitals. In terms of quality control, only 11.5% (20/174) hospitals implemented all four measures. In terms of polypectomy techniques, 98.1% (203/207) colonoscopists chose hot snare polypectomy or endoscopic mucosal resection for lesions of diameter>1 cm, while options varied for lesions of diameter<1 cm. The interval of follow-up after polypectomy recommended by colonoscopists was shorter than that by guidelines.Conclusion:Several problems are found in the survey in the application of colonoscopy in China, i. e., patient education of bowel preparation is not diversified; quality control of colonoscopy still needs to be strengthened; polypectomy techniques and follow-up after polypectomy need to be further standardized.

Objective:To investigate the consistency of myocardial extracellular volume between systole and diastole using dual-layer detector spectral CT.Methods:This was a cross-sectional study. Thirty-five patients who underwent cardiac spectral CT examination in West China Hospital of Sichuan University from April 2022 to December 2022 were retrospectively collected. Hematocrit was collected within 3 days before the CT scan. The delayed phases holographic spectral images in systole (45%) and diastole (75%) were obtained using dual-layer spectral CT. CT data were processed using a spectral post-processing workstation, and the extracellular volume (ECV) based on iodine density images, referred as CT-ECV, in systolic and diastolic phases were calculated, respectively. According to the American Heart Association′s 16-segment model of left ventricular, the standard short-axis images were constructed, and the myocardium was standardized into 16 segments at the basal, mid-cavity, and apical levels of the left ventricle. Two radiologists performed a subjective evaluation in the image quality of the CT-ECV images of the whole heart and the three sections in systole and diastole using a "five-point" scale. The ECV of the 16 segments and the whole heart in systole and diastole was calculated. The consistency of subjective evaluations between systole and diastole was assessed using Kappa statistics. Wilcoxon signed-rank tests were used to compare the differences in scores between systole and diastole. Paired sample t-test was used to compare the differences in CT-ECV scores between systole and diastole. The intraclass correlation coefficient was used to test the intra-and inter-observer consistency of CT-ECV measurements between two radiologists. P<0.05 was statistically significant. Results:There was good agreement between the two radiologists on subjective scores of CT-ECV image quality between systole and diastole ( Kappa>0.80), and there was no statistical difference in image quality among the basal, mid-cavity, and apical levels of the left ventricle and whole heart between systole and diastole ( P>0.05). The systolic and diastolic CT-ECV for the entire heart obtained through the delay phase were (33.29±3.46)% and (33.50±3.39)%, respectively, with no statistically significant difference ( t=-0.78, P=0.442). CT-ECV in systole and diastole were (34.15±3.94)% and (35.30±3.99)% for segment 8, (34.03±3.76)% and (35.46±3.74)% for segment 9, and (33.98±3.32)% and (35.05±3.98)% for segment 14, respectively. The mean values of the systolic CT-ECV of segments 8, 9 and 14 were significantly lower than those of diastolic CT-ECV ( t=-2.65, -3.26, -2.42, P=0.012, 0.003, 0.022, respectively). The ICCs for CT-ECV measurements of 16 segments by the two radiologists were greater than 0.90 in both systolic and diastolic, indicating good agreement. Conclusions:There is no significant difference in whole heart CT-ECV values between systolic and diastolic myocardial ECV based on dual-layer spectral CT. However, minor differences (less than 2%) are found between systolic and diastolic myocardial CT-ECV for some segments. Myocardial CT-ECV measurement should be performed on the same segment during the same phase to obtain stable and accurate ECV values.

Objective:To examine the impact of pressure support ventilation(PSV)in combination with low inspired oxygen concentration on atelectasis during the emergence from general anesthesia in elderly patients undergoing robotic-assisted radical prostatectomy.Methods:In this prospective randomized controlled study, a total of 144 elderly patients, aged 65-80 years(average age: 71.4±4.4 years), who were undergoing elective robotic-assisted radical prostatectomy under general anesthesia, were divided into 4 groups(n=36 each)using the random number table method.The groups were as follows: PSV+ 40% fraction of inspiration oxygen(FiO 2)(P40 group), PSV+ 80%FiO 2(P80 group), spontaneous breathing+ 40%FiO 2(S40 group), and spontaneous breathing+ 80%FiO 2(S80 group). These methods were used during the general anesthetic emergence, which refers to the period from the end of the operation to extubation.Atelectasis aeration loss score was measured using ultrasound, and the oxygenation index(OI)was calculated through arterial blood gas analysis.These measurements were recorded at different time points: at the end of surgery(T 1), after extubation(T 2), 30 minutes after entering the post anesthesia care unit(PACU)(T 3), and 48 hours after surgery(T 4). The number of hypoxemia cases(defined as saturation of pulse oxygen <92%)during emergence and within 30 minutes of entering the PACU, as well as the incidence of postoperative pulmonary complications(PPCs)at T 4, were also recorded. Results:A total of 137 patients completed the study.Compared with the P40 group, the patients in the P80 group had higher atelectasis aeration loss scores at T 2[6.0(3.0)scores vs.4.0(2.0)scores; Z=-3.733, P<0.001], the S40 group[8.0(3.0)scores vs.4.0(2.0)scores; Z=-4.868, P<0.001], and the S80 group[9.0(3.0)scores vs.4.0(2.0)scores; Z=-6.835, P<0.001]. At T 3, the S40 group[7.0(2.0)scores vs.5.0(2.0)scores; Z=-4.631, P<0.001]and the S80 group[9.0(2.5)scores vs.5.0(2.0)scores; Z=-6.590, P<0.001]also had higher atelectasis aeration loss scores.There was no significant difference in the incidence of hypoxemia between the four groups during the recovery period( χ2=0.405, P=0.939)and in PACU( χ2=4.048, P=0.256). The incidence of PPCs in the four groups at 48 hours after operation was 5.9%(2/34), 11.4%(4/35), 8.6%(3/35), and 6.1%(2/33)respectively( χ2=0.947, P=0.814). Conclusions:The combination of positive end-expiratory pressure support ventilation(PSV)and low inspired oxygen concentration can effectively decrease the occurrence of atelectasis in elderly patients undergoing robotic-assisted radical prostatectomy during the emergence phase.This approach also helps in reducing the incidence of hypoxemia in the post-anesthesia care unit(PACU)and improves the postoperative oxygenation index.