Objective To investigate the alteration of peripheral tissue`s temperature of the coagulation zone of microwave ablation in brain tissue, and to provide experimental evidence for clinical application. Methods Twelve canines were treated by microwave ablation in brain tissue. Each was ablated for 180 s with microwave output power of 20 W, 30 W, and 40 W. During the operation the peripheral temperature at the distance of 0.5 cm, 1.0 cm, 1.5 cm and 2.0 cm from the ablation center was recorded respectively. The ultrasound was performed 1 hour after the operation, and then the animals were executed and the microscopic changes of the ablation lesion were observed. Results Eleven canines suffered well for the ablation, while 1 presented abnormal respiration during the operation and died 2 hours later. During the operation, the temperature of the area 0.5 cm from the center rose signiifcantly, with the maximum temperature was (96.40±1.46)℃at the power of 20 W, and 100℃at the power of 30 W and 40 W. The temperature of the area 1.0 cm from the center rose faster, with the maximum temperatures at different powers all above the 46℃. The temperature of the area 1.5 cm from the center rose slower, with the maximum temperature below 46℃at the power of 20 W and 30 W and above 46℃at the power of 40 W. The maximum temperatures of the area 2.0 cm from the center at different powers were all below 46℃. The difference of the maximum temperature at different distances (1.0 cm, 1.5 cm, and 2.0 cm from the center) was signiifcant (F=776.78, 2640.64 and 3025.53, all P<0.05). The length and width of the ablation lesion as well as the area of edema increased with the power. At the power of 20 W, 30 W, and 40 W, the length of the ablation lesion was (29.3±1.8) mm, (32.7±2.1) mm and (34.2±2.4) mm, the width was (22.5±1.5) mm, (23.7±1.7) mm and (27.1±2.0) mm, and the width of the edema zone was (2.3±0.4) mm, (2.6±0.4) mm and (2.7±0.5) mm. The differences of the length and width of the ablation lesion at different powers were signiifcant (F=11.46, 14.49, both P<0.01). The difference of the edema area at different powers was insigniifcant (F=1.94, P=0.169). Conclusions Microwave ablation is a safe therapeutic modality. However, the shorter distance from the ablation center and greater ablation power give rise to larger ablation lesion, higher maximum temperature, and faster temperature increase. Therefore, 2.0 cm from the ablation center is a safe area.

Objective To study the effect of Perfadex and Wisconsin Unviersity solution on the function of pulmonary artery endothelium.Methods Small lobe pulmonary arteries were dissected from nine porcine lungs.The artery from each lung was cut into six rings in 2mm.Two of them were randomly incubated in Krebs,Perfadex or Wisconsin Unviersity solution (UW solution) at 4℃ for 4 hours.Endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation (percentage of-7.5 logM U46619 precontraction) induced by bradykinin or calcium ionophone A23187 in the present of indomethacin,L-NNA and oxyhemoglobin were measured at 37 ℃ in the organ chambers.Results Vasoconstriction induced by U46619 is no significant difference among three groups (P＞ 0.05).Compared with Krebs group,the relaxation induced by bradykinin or A23187 was significantly decreased in Perfadex group (P＜0.01),while there is no significant difference in UW group (P＞0.05).Conclusion Endothelium-derived hyperpolarizing factor (EDHF) plays an important role in endothelium-mediated relaxation of porcine pulmonary artery.EDHF-mediated relaxation is impaired when the lung preserved with Wisconsin Unviersity solution,wheras its function is not affected by Perfadex solution.

Objective To detect the recombinant intermediates of hepatitis B virus (HBV) between genotype B and C in vitro. Methods Vector Plenti6/V5-D-topo-X was genetically modified by genotype B and C to transfect HepG2 cells. Then the HepG2 cells were amplified and sequence of the nucleic acid after the transinfection was tested and compared with RDP3Beta40 software package and bootscanning procedure in SimPlot program package. Results Three recombinant intermediates of HBV between genotype B and C were identified in vitro. Genotype C in the precore region plus the core gene spanning nucleotide positions from 1740-1838 to 2443-2485 contributed to the recombination with genotype B. Isolate R1 recombinant intermediate had 2 break points at nt2170-2172 and nt2188-2189. Nucleic acid changed from CAC to TGT and from GA to AC, respectively. Isolate R2 recombinant intermediate had a break point at nt1740-1 838, and 3 bases changed in different nucleic acid sites: from A to T at nt1740, from C to T at nt1753, and from G to A at nt1838, respectively. Isolate R3 recombinant intermediate had a break point at nt2443-2483, and 4 bases changed in different nucleic acid sites: from C to T at nt2443, from A to G at nt2452, from T to C at nt2480, and from C to T at nt2483, respectively. Conclusion The recombinant intermediates of HBV between genotype B and C have been detected in vitro and the changes have been identified in the precore region plus the core gene in genotype B and C.

OBJECTIVETo investigate the operative reduction techniques and clinical results of surgical treatment of type C1 (AO/ASIF) acetabular fracture by posteroproximal-posteroanterior sequential reduction and internal fixation.

METHODSFrom August 2004 to January 2012, 13 patients with type C1 (AO/ASIF) acetabular fracture were treated by posteroproximal-posteroanterior sequential reduction and internal fixation. Of them, 8 cases were male and 5 cases were female with an average age of 42 years years old (ranged, 18 to 64). Pelvis 3-dimentional CT reconstruction were used to confirmed the classification of fracture, and the operation were performed during from 5 to 20 days with an average of 9.5 days. Operation time, blood loss, complications and reduction were recorded and evaluated. The function of hip joint were accessed at the final follow-up.

RESULTSThe operation time ranged from 190 to 290 min with an average of 240 min. The mean blood loss was 1 800 ml (ranged, 1 300 to 3 000 ml). One case had superficial infection and healed after 3 weeks. According to Matta reduction criteria, 8 cases obtained anatomical reduction, 4 cases got satisfied results and 1 cases got unsatisfied results. Eleven cases were followed up with an average of (24.0 +/- 8.0) months, and 2 cases were lost to follow-up. According to revised Mede d'Aubingne and Postel evaluation system, 7 cases got excellent results, 2 good, 1 moderate and 1 poor.

CONCLUSIONPosteroproximal-posteroanterior sequential reduction and internal fixation for the treatment of type C1 (AO/ASIF) acetabular fracture can achieve satisfied surgical proces and operation quality.

Acetabulum ; diagnostic imaging ; injuries ; surgery ; Adolescent ; Adult ; Female ; Fracture Fixation, Internal ; Hip Fractures ; diagnostic imaging ; surgery ; Hip Joint ; diagnostic imaging ; surgery ; Humans ; Male ; Middle Aged ; Radiography ; Treatment Outcome ; Young Adult

Objective:To retrospectively analyze the clinical characteristics of elderly patients who received colonoscopy and to explore the clinical value of regular colonoscopy for the elderly.Methods:This was a retrospective cohort study.A total of 1 154 patients aged 75 years and over undergone colonoscopy in Guangdong General Hospital from January 2015 to March 2018 were enrolled and divided into three groups, including 605 cases aged 75-79 years, 527 cases aged 80-89 years and 22 cases aged 90 years and over.Detection rates of colorectal lesions by colonoscopy were recorded.The clinical value of annual colonoscopy on the detection of colorectal lesions in elderly patients 75 years and older were analyzed to assess the necessity for regular monitoring.Results:Overall, 569 cases(49.3%)underwent colonoscopy with sedation and 585 cases(50.7%)underwent colonoscopy without sedation.The total positive detection rate was 83.4%(962/1 154), and the main lesions were polyps(858 cases, 74.4%), including 605(52.4%)cases of adenomas.Among the three groups, gastrointestinal bleeding was the main cause for colonoscopy in the group aged 90 years and over, while abdominal discomfort, elevated immunological tumor markers and history of non-colon cancer were the main reasons for colonoscopy in the group aged 75-79 years( P<0.05). A total of 153 cases underwent annual colonoscopy.The detection rate of polyps and adenomas decreased in the second exam, but still higher than 40.0%. Conclusions:Colonoscopy is a safe and effective method for the elderly population aged 75 years and over.Polyps and adenomas are the most common lesions.Recurrence of polyps after colorectal cancer and polypectomy is common and it is necessary to receive colonoscopy regularly.

Objective:To isolate and culture WU polyomavirus (WUPyV), and to analyze the genome-wide evolutionary patterns, homology and population dynamics.Methods:Real-time quantitative PCR was used to detect the nasopharyngeal aspirate samples of hospitalized children with respiratory tract infection in Beijing Friendship Hospital during 2020 to 2022. Primary human airway epithelial cells cultured at the air-liquid interface were used to isolate and culture WUPyV. Whole genome sequence of the isolated strain was obtained by Sanger sequencing. For phylogenetic and evolutionary dynamics analysis, the whole genome was compared with the published whole genome sequences in GenBank database.Results:The detection rate of WUPyV was 4.7% (31/659) during 2020 to 2022, and a clinical strain BJ0593 of WUPyV type Ⅲc was successfully isolated. The homology of the whole genome and gene fragments of WUPyV was high. The average evolutionary rate of VP2 gene was about 1.256×10 -4 substitution/site every year, and the population dynamics of WUPyV tended to be flat in the last decade. Conclusions:This study successfully isolated a clinical WUPyV type Ⅲ strain for the first time, which provided the basis for further investigation on the molecular evolution and pathogenicity of WUPyV.

Objective To analyze the distribution characteristics of injuries among students in Songjiang district, Shanghai, and to provide data support for preventing injuries among students. Methods Data of injury cases among school students in Songjiang from 2017 to 2019 were collected from the National Injury Surveillance System (NISS), and the demographic characteristics, injury occurrence and clinical characteristics of injuries were analyzed. Results A total of 13 877 cases of injuries in school students were reported from 2017-2019, with a sex ratio of 1.94:1. The education level of the injured students was mainly primary school. The peak incidence months of student injuries were May (9.97%) and November (9.67%). Falls (50.83%) were the leading cause of student injuries, and the top three places of student injuries were at home (30.08%), in schools and public places (28.11%) and on roads/streets (22.97%). The top three activities at the time of the injury were leisure activities (34.62%), sports activities (18.50%), and taking transportation（17.68%）. The top three injury types were bruise/scratch (42.94%), sprain/strain (28.67%) and sharps/bite/open injury (13.53%). The common injury parts were lower limbs (38.39%), head (27.82%) and upper limbs (24.88%). Conclusion The prevention of injuries in school students in Songjiang should focus on male students and low age students, and targeted injury prevention and control work for students of different ages should be carried out.

Objective:To construct 2019 novel coronavirus (2019-nCoV) 614D and 614G pseudovirus by HIV lentivirus packaging system and explore their biological specificity.Methods:The recombinant expression plasmids pCDNA3.1-614D and pCDNA3.1-614G were transiently cotransfected with psPAX2 and pLenti CMV Puro LUC into 293T cells respectively. After 72 hours, the supernatant was collected and ultracentrifuged with 20% sucrose cushion. The titer, morphology, protein expression and neutralizing activity of pseudovirus were determined.Results:S protein specific fluorescence was detected by indirect immunofluorescence test, Western blot analysis showed S protein was expressed, and the spike of pseudovirus was observed under transmission electron microscope. The titers of pseudovirus 614D and 614G were 1.12×10 4 and 2.52×10 4 TCID 50/ml, respectively. The pseudovirus 614D and 614G could be neutralized by S rabbit polyclonal antibody, indicating that the pseudovirus has high specificity. Conclusions:In this study, 2019-nCoV 614D and 614G pseudovirus was successfully constructed, which laid the foundation for the establishment of in vitro neutralizing antibody detection platform based on pseudovirus.

The standardized workflow of computer-aided static guided implant surgery includes preoperative exami-nation,data acquisition,guide design,guide fabrication and surgery.Errors may occur at each step,leading to irrevers-ible cumulative effects and thus impacting the accuracy of implant placement.However,clinicians tend to focus on fac-tors causing errors in surgical operations,ignoring the possibility of irreversible errors in nonstandard guided surgery.Based on the clinical practice of domestic experts and research progress at home and abroad,this paper summarizes the sources of errors in guided implant surgery from the perspectives of preoperative inspection,data collection,guide de-signing and manufacturing and describes strategies to resolve errors so as to gain expert consensus.Consensus recom-mendation:1.Preoperative considerations:the appropriate implant guide type should be selected according to the pa-tient's oral condition before surgery,and a retaining screw-assisted support guide should be selected if necessary.2.Da-ta acquisition should be standardized as much as possible,including beam CT and extraoral scanning.CBCT performed with the patient's head fixed and with a small field of view is recommended.For patients with metal prostheses inside the mouth,a registration marker guide should be used,and the ambient temperature and light of the external oral scan-ner should be reasonably controlled.3.Optimization of computer-aided design:it is recommended to select a handle-guided planting system and a closed metal sleeve and to register images by overlapping markers.Properly designing the retaining screws,extending the support structure of the guide plate and increasing the length of the guide section are methods to feasibly reduce the incidence of surgical errors.4.Improving computer-aided production:it is also crucial to set the best printing parameters according to different printing technologies and to choose the most appropriate postpro-cessing procedures.

Objective:To study the sequence characteristics and genetic variation of a human respiratory syncytial virus (HRSV) subtype A genome in Beijing.Methods:The genomic RNA of HRSV from nasopharyngeal aspirate samples was sequenced and obtained a whole genome sequence of HRSV A subtype. The phylogenetic tree was constructed with reference sequences of other HRSV strains. The major proteins were compared and single nucleotide polymorphism analyzed. In addition, the N-glycosylationsites of F and G protein were predicted.Results:Phylogenetic tree and homology analysis results suggest that the HRSV strain (RSVA/Beijing-China/2017) was the A subtype ON1 genotype. Nucleotide and amino acid variation analysis showed that G protein, F protein and L protein had some substitutions. Analysis of amino acid variation sites showed that amino acid substitution (L142S) occurred at position 142 of G protein. For F protein, there were two substitutions, which were S105N in the P27 peptide (110-136aa) and C69Y in the antigen sites ? (62-69 aa and 196-210 aa). The prediction of N-glycosylation sites revealed that there were 5 N-glycosylation sites of F protein and 4 N-glycosylation sites of G protein in this strain.Conclusions:The HRSV strain obtained in Beijing belongs to A subtype ON1 genotype. The G, F and L proteins have large variations, and 22 amino acid substitutions have occurred in the G and F proteins.