The interaction between the antibody and the corresponding target molecule determines the characteristics of immunoassay. In this study, a single chain variable fragment antibody (scFv4C7) derived from the hybridoma strain 4C7 were prepared via genetic engineering technique. The recognition properties of scFv4 C7 was determined and compared to those of the parent monoclonal antibody by indirect competitive enzyme-linked immunosorbent assay(ic-ELISA). Three dimensional structure of the scFv4C7 was presented by Swiss-Model, and sulfathiazole ( STZ) was docked to the scFv4C7 model to obtain the structure of the binding complex. The results from the ic-ELISA showed that the binding properties of scFv4C7 were comparable with the parent monoclonal antibody and STZ was almost completely buried in a deep binding pocket formed by the heavy chain and light chain of the antibody. The interaction between STZ and scFv4C7 was more closely related to the heavy chain and the complementarity-determining region ( CDR ) H3 loop played more important role than other CDR loops. The study preliminary provided the necessary structural information for the preparation of antibody with broader specificity and higher affinity.

Objective To evaluate the clinical and imaging characteristics of osteoid osteoma in femoral neck and to improve diagnostic accuracy of this disease.Methods Twenty-one patients (18 males and 3 females,age,7-26 years,median age,13 years) with pathologically proven osteoid osteoma of the femoral neck were retrospectively analyzed for their clinical profile and radiologic features.CT and X-ray examinations were performed in all patients,10 of them pefformed post-contrast CT scan and 4 of them performed MRI examinations.Results Nineteen patients had hip pain (pain worse at night in 11,and 8 received salicylates treatment with good response),and 2 patients only with intermittent claudication.The duration ranged from 2 months to 54 months (median duration 12 months).X-ray: Nidus was seen on plain film in 10 cases,18 cases showed different degrees of bone sclerosis of the nidus.CT: Nidus was demonstrated in all cases.Among them,8 were intracortical,6 were subperiosteal,7 were endosteal.Twenty cases showed different degrees of bone sclerosis of the nidus-extra-articular anteromedial cortical surface of the femur neck.Nineteen cases showed vascular groove sign.MRI: Nidus was seen in 4 cases.Bone sclerosis was low signal on all sequences.Three cases had joint effusion,4 cases had bone marrow edema,and 2 cases had synovial thickening.Conclusions Although osteoid osteoma of femoral neck has non-specific clinical features,the radiographic findings are usually typical.The nidus of osteoid osteoma is often located within the joint.Bony sclerosis occurs at the area of extra-articular anteromedial cortical surface of the femur neck.CT examination remains an optimal method to identify the nidus.

Objective To investigate the expression of endostatin and angiopoietin (Ang)-2 in human ghoma and its significance. Methods The expression of endostatin and Ang-2 were measured by immunohistochemistry and endostatin mBNA by hybridization in situ in 108 cases of brain glioma and 5 cases of normal brain tissues. Results The expression of endostatin (0.0657±0.0038)and Ang-2 (0.0286± 0.0042) were significantly higher in grade Ⅲ-Ⅳ glioma patients than those in grade Ⅰ-Ⅱ ghoma patients (0.0349±0.0048,0.0084±0.0018, respectively) and normal brain tissues (0,0)(P<0.01). The expression of endostatin mRNA were significantly higher in grade Ⅲ-Ⅳ glioma patients (0.0310±0.0041) than that in grade Ⅰ-Ⅱ glioma patients (0.0152±0.0031) and normal brain tissues (0)(P< 0.01 ). Theratio of endo-stalin to Ang-2 was negatively rehted to the grade of glioma (r=-0.810,P <0.01). Conclusion The interaction of endostatin and Ang-2 plays an important role in the invasive growth and malignant development of human glioma, and may be related to the prognosis and the malignant degree of glioma.

Objective To evaluate the efficacy and safety of the flexible ureteroscopy (FURS) with holmium laser lithotripsy in the management of stones in ectopic pelvic kidney (PK).Methods We retrospectively reviewed the records of 11 patients,ranged from 37-52 years old,who were underwent FURS with holmium laser for PK stones from January 2007 to April 2012.Three cases had solitary stones in renal pelvis,3 cases had solitary stones at lower calyx and multiple stones were found in 5 cases.Mean size of stone was 2.3 cm (ranged 1.8-3.7 cm).One case had history of ESWL and PCNL before surgery with unsatisfied result and 7 cases were underwent ESWL with poor outcome.The double J stent was placed into the ureter two weeks before the operation.Under the general anesthesia,the ureteral access sheath was placed firstly during operation.Then,flexible ureteroscopy was inserted into the renal pelvis through ureteral access sheath.Holmium laser was used to perform the procedure with the power less than 20 W (0.6-1.0 J/10-20 Hz).The stone fragments were taken out by stone baskets and double-J stent was set at the end of the procedure for additional two weeks.Results The successive rate of the ureteroscopic insertion was 100％.The average operation time was 62 min (ranged 31-87 min).No severe complications such as heavy bleeding,perforation or ureteral avulsion occurred.Small stone fragments were found in 3 cases.All of them located in the lower calyx.Since no one complained about the upper urinary obstruction or related symptoms,conservative observation was considered.All patients discharged the day after the operation.Within three months follow-up,no sign of urinary obstruction was found.Conclusions FURS with holmium laser is a safe,effective and minimally invasive technique.It could be the best option in the management of renal calculi in ectopic pelvic kidney.

Objective: To explore the chain mediating effect of regulatory emotional self efficacy and positive psychological capital on resilience and the mental health of college students. Methods: A total of 809 college students of Chaohu University were selected and were administered with the the Self report Symptom Invertory, Symptom Checklist,90 (SCL-90), Connor Davidson Resilience Scale (CD-RISC), Regulatory Emotional Self efficacy Scale (RES-C) and Positive Psychological Capital Questionnaire (PPQ). Multiple linear regression analysis was performed, taking resilience, regulatory emotional self efficacy and positive psychological capital as independent variables and the mental health of college students as dependent variables, meanwhile test the intermediary effect. Results: Differences were found in resilience(3.52±0.55,3.27±0.42), regulatory emotional self efficacy(3.58± 0.59 ，3.32±0.57), positive psychological capital(4.74±0.77，4.49±0.76) and mental health(158.66±33.01，176.53±34.73) among college students with different sources(urban and rural)( t =55.82，39.22，21.28，-54.14， P <0.05). Resilience, regulatory emotional self efficacy and positive psychological capital were significantly associated with the severity of mental health of college students( R 2= 0.21, P <0.01). Regulatory emotional self efficacy and positive psychological capital played a significant chain mediating role between resilience and poor mental health( effect =-0.03, P <0.05), and the mediating effect accounted for 39.3% of the total effect. Conclusion The mental health of college students can be improved by strengthening levels of resilience and enhancing regulatory emotional self efficacy, and constructing positive psychological capital could contribute to the association between resilience and mental health.

Objective:To investigate the prognostic factors that influence Barcelona (Barcelona clinical liver cancer staging system, BCLC)stage B hepatocellular carcinoma patients after hepatectomy.Methods:Retrospective analysis was made on clinical and pathological data of 50 standardized hemihepatectomy in Barcelona stage B hepatocellular carcinoma from 2013 to 2017.Results:Single-factor results showed that high expression of tumor microvascular invasion (MVI) and proliferation of nuclear antigen (Ki-67) were the prognostic factors ( respectively χ 2 =8.411, 10.939, all P<0.05). Multivariate analysis showed that the difference of high expression of Ki-67 and survival rate was statistically significant (respectively F=5.710, 8.254, all P<0.05). Ki-67 expression level and tumor differentiation were statistically significant (χ 2=0.497, P<0.05). There was a statistically significant difference in survival between the high-risk group and the low-risk group according to the risk factors (χ 2=12.152, P<0.05). Conclusions:MVI and high expression of Ki-67 were high risk factors affecting the overall survival rate of liver cancer after hemihepatectomy.

Objective: This study aimed to explore the relationship between childhood sexual abuse (CSA) and sexual orientation among college students, and to explore possible sex difference. Methods: By using multi-stage stratified cluster sampling method, 4 034 students were selected from 4 college schools. Self-made questionnaire was used to collect the demographic information, CSA experiences and sexual orientation. Logistic regression models were conducted to examine sex differences in the relationship between different types and timing of CSA and sexual orientation. Results: The reporting rates of heterosexual, homosexual, bisexual and asexual orientation of college students were 93.2%, 0.7%, 3.7% and 2.4%, respectively. For males, contact CSA (OR=14.70, 95%CI=5.73-37.72), both contact and noncontact CSA (OR=4.33,95%CI=1.91-9.84) in elementary school or earlier were associated with sexual orientaion. non-contact CSA (OR=4.20, 95%CI=2.21-7.98), both contact and noncontact CSA (OR=3.57, 95%CI=1.65-7.70) in middle school were related to sexual orientation. However, for females, non-contact CSA (OR=1.78, 95%CI=1.02-3.13) and both contact and non-contact CSA (OR=3.13, 95%CI=1.35-7.23) in elementary school or earlier were associated with sexual orientation. Conclusion CSA experiences are associated with sexual orientation in sex-specific manner, with significant stronger association among males.

Objective:Objectives The aim of the study is to evaluate the mechanical performance, safety and efficacy of the novel robotic-assistant flexible ureteroscopy system (Ra-fURS) under in vitro and in vivo environments.Methods:Combing with commercial flexible ureteroscopes, the novel Ra-fURS was used for the in vitro test and animal model operation in October 2020. The study included three sections. ①Basic mechanical performance assessment: including endoscope motion control (dual deflection, axial rotation and forward/backward distance), reaction time and fiber regulation. ②Simulated surgery in ex-vivo 3D-printing renal collecting system model: including completion rate and time of calyxes exploration, directional movement and laser fragmentation [gypsum models (0.5×0.5×0.5 cm) were used to stimulate kidney stones]. ③Intrarenal surgeries in animal models (two 5-month female Yorkshire white pigs). In total, 32 surgeries was performed (8 surgeons × 2 pigs × 2 kidneys/pig). In vivo assessments were carried out including: ①consuming time for Ra-fURS installation and offloading; ②completion rate and time of calyxes exploration; ③comfort score (ranging from 0-10) as compared to the manual f-URS, which was corresponding to each Ra-fURS surgery. In simulated surgery and animal surgery sections, 8 surgeons were enrolled in the study (group A 4 without flexible ureteroscopy experience; group B: 4 highly experienced), and results were compared between two groups.Results:Under the Ra-fURS control, the flexible ureteroscope movement in three degrees of freedom (forward / backward: + 11 to -11 cm, axial rotation + 225°to -225°; active duel-flection: + 270°to -270°, as well as the laser fiber regulation + 2.5 to -2.5 cm). In simulated surgery tests, both groups achieved 100% completion rate of calyxes exploration, and there were no statistical differences in the time of the calyxes exploration between group A and group B (116.0±8.0)s vs.(110.3±15.4)s( P>0.05). Time-consumption for laser fragmentation of group B was shorter than that of group A (525.8±58.5)s vs. (780.5±141.2)s( P<0.01). In animal surgery, the installation time of Ra-fURS gradually shortened within the first 7 cases was(234.0±43.0)s, and became comparable in the later 8-32 cases was(149.3±8.0)s. The average uninstall time was (43.9 ±5.9)s and was relatively stable. There were 51 renal calyxes in two pigs. It was higher for the completion rate of calyxes exploration in group B than in group A [(95.5±9.1)% vs. (59.1±9.1)%, P<0.05], and the exploration time was also statistically variant between the two groups group A and group B[(274.8±34.6)s vs.(127.3±18.2)s, P<0.05]. For all the operators, the comfort scores were favorable to the Ra-fURS as compared to the manual f-URS (8.9±0.3 vs. 5.9±1.1, P<0.05). Conclusions:This preliminary study demonstrated that the novel Ra-fURS was capable of controlling flexible ureteroscope to perform retrograde intrarenal surgery and fragmenting stones with laser. Besides, other features, including easy installation, stable performance and comfortable manipulating environment, made it easy to use in clinical application.

Abstract Adolescent cyberbullying refers to adolescents who are subjected to offensive and violent behavior in social network environments through electronic technologies. Due to the anonymity of the Internet and the rapidity of transmission, cyberbullying has a serious and far reaching impact on the physical and mental health of teenagers. With the development of information technology, various forms of cyberbullying have emerged, and the formation mechanism and influencing factors of cyberbullying are diverse and complex. This article systematically reviews the research progress in cyberbullying by evaluating the epidemic characteristics, influencing factors, and related theoretical models that are relevant to adolescents, so as to provide a referential framework to build a public health system that can prevent cyberbullying in families, schools, and society.

Objective To study the effect of diffusion-weighted magnetic resonance imaging (DW-MRI) in the differential diagnosis of hydronephrosis and pyonephrosis.Methods From March 2015 to October 2017,50 patients with renal stone and highly suspected infectious hydronephrosis underwent renal DW-MRI,and clinical materials were collected and analyzed retrospectively.Seventeen male and 33 female patients were enrolled with a mean age of (49.40 ±-10.51) years.The median maximum diameter of renal stone was 30.30 (17.38,56.01) mm and hydronephrosis was 46.39 (34.33,56.55) mm.No pyonephrosis was diagnosed by preoperative ultrasound or CT,while 29 cases of hydronephrosis and 21 cases of pyonephrosis were reported by preoperative DW-MRI.Final diagnoses of hydronephrosis and pyonephrosis were made according to whether the pelvic urine drainage was purulent or not during the surgery.DW-MRI reports and characteristics of DW images were analyzed retrospectively.Apparent diffusion coefficient (ADC) was calculated and ADC map constructed,which was compared between the two groups.Receiver operating characteristic curve (ROC) was drawn to analyze the area under curve (AUC) and the optimal cutoff of ADC value,with sensitivity and specificity.Results Thirty-three patients of hydronephrosis and 17 pyonephrosis were confirmed intraoperatively.The overall accuracy of diagnosis using DW-MRI was 84.00％ (42/50),with sensitivity of 88.24％ (15/17) and specificity of 81.82％ (27/33).Among 30 patients who underwent CT scan in our hospital,mean CT value of 18 hydronephrosis was (7.03 ± 3.26)HU and that of 12 pyonephrosis was (8.67 ± 3.52) HU,with no statistical significance (P ＞ 0.05).On DW image,when b ≥ 500 s/mm2,hydronephrosis signal intensity was lowered apparently,whereas pyonephrosis signal intensity was intensified.On ADC map,hydronephrosis appeared as hyperintensity,whereas pyonephrosis appeared as hypointensity.The mean ADC value of pyonephrosis group was lower than hydronephrosis group [(1.53 ±0.58) × 10-3 mm2/s vs.(2.86 ±0.56) × 10-3 mm2/s,p ＜0.01].ROC analysis revealed that AUC =0.92 (95％ CI 0.80-0.98),and the cut-off value of ADC for pyonephrosis diagnosis was 1.39 × 10-3 mm2/s,of which the sensitivity and specificity was 94.12％ and 84.85％ respectively.Conclusions Signal of pyonephrosis was enhanced on DW image,while decreased on ADC image.The ADC value of pyonephrosis was much lower than that of hydronephrosis,with which the differential diagnosis between pyonephrosis and hydronephrosis could be made efficiently.