Objective:To establish an antibody expression system to reduce the antibody-dependent enhancement (ADE) effect of target antibody.Methods:Site-directed mutagenesis was used to mutate the 234 and 235 sites of the Fc region of the mammalian cell antibody expression vector-L234A and L235A to establish the antibody expression vector pFRT-IgG1κ-FcM. An antibody Wt-WNV with significant ADE effect obtained in previous work was selected and expressed by the pFRT-IgG1κ-FcM system to obtain mutant antibody FcM-WNV. The binding ability of FcM-WNV to target antigen West Nile virus envelope protein-DⅢ (WNV E-DⅢ) was detected by ELISA, and the its binding ability to human high-affinity IgG Fc receptor hFcγRⅠ (hCD64 ) was analyzed by flow cytometry. The neutralizing activity of FcM-WNV in vitro was detected by pseudovirus infection of host cells (BHK21 and K562). Results:The expression levels of FcM-WNV and Wt-WNV were comparable, and FcM-WNV could recognize and bind to WNVE-DIII in a concentration-dependent manner. Compared with Wt-WNV, the binding ability of FcM-WNV to hCD64 was significantly weakened, showing a significant decrease in fluorescence intensity. Consistent with the previous experimental results, Wt-WNV at a concentration of 5 μg/ml significantly enhanced the infection of K562 by WNV pseudovirus, while FcM-WNV at a concentration of 5 μg/ml could effectively block pseudovirus infection in both K562 and BHK21 cells.Conclusions:The established antibody expression system can effectively reduce the ADE effect of the target antibody.

Objective:To establish an in vivo infection model of West Nile virus (WNV) pseudovirus and evaluate the neutralizing activity of antibody WNV-XH1.Methods:A stable cell line that can package the WNV pseudovirus was established in the early stage to prepare the pseudovirus supernatant. The supernatant was concentrated and infected BHK21 cells to detect the titer of the pseudovirus. After intraperitoneal injection of the pseudovirus into C57BL/J mice, bioluminescence imaging was performed to observe the infection status of the pseudovirus in the mice. After simultaneous infection, blood was collected and ELISA was used to detect NS1 levels in mouse serum. The in vivo functional activity of antibody WNV-XH1 was evaluated using the established mouse infection model.Results:Fluorescence was detected in C57BL/J mice infected with WNV pseudovirus, and the NS1 levels in the peripheral blood serum of mice infected with pseudovirus were significantly higher than those of non infected mice (1.453±0.09vs0.305±0.018). After intravenous administration of WNV-XH1 antibody before the attack, the fluorescence signal in the mice decreased and the serum NS1 level decreased (0.384±0.015).Conclusions:A successful in vivo infection model of WNV pseudovirus was established, and it was confirmed that the antibody WNV-XH1 had a protective effect against WNV pseudovirus infection in vivo.

Objective:To analyze the effects of chronic obstructive pulmonary disease (COPD) combined with obstructive sleep apnea hypopnea syndrome (OSAHS) on hypercapnia and its related factors.Methods:In this cross-sectional study, patients with stable COPD were continuously recruited from July 2016 to December 2018 in the Respiratory Department of Peking University Third Hospital. General clinical data of patients were collected, and lung function test, arterial blood gas analysis and portable sleep monitoring were also conducted. Patients with COPD complicated with apnea hypopnea index (AHI)≥10 times/h and apnea events being mainly blockage-type events, accompanied by snoring, sleep apnea, daytime sleepiness and other symptoms were defined as overlapping group, patients with COPD complicated with AHI<10 times/h were defined as simple COPD group. Correlation analysis and logistic regression model were used to explore the determinants of daytime hypercapnia in patients with COPD.Results:Compared with simple COPD group, the median arterial partial pressure of carbon dioxide (PaCO 2) was significantly higher in the overlapping group (42.00 vs 38.95 mmHg (1 mmHg=0.133 kPa), P<0.001), and the rate of daytime hypercapnia was significantly higher (23.3% vs 3.3%, P=0.002). PaCO 2 was correlated with forced vital capacity (FVC), percent predicted forced expiratory volume in one second (FEV 1%pred), the ratio of residual volume (RV) to total lung capacity (TLC), AHI, nocturnal average transcutaneous oxygen saturation (SpO 2), nocturnal minimum SpO 2 and the total sleep time spent with SpO 2≤90% (T90) (all P<0.05). In logistic regression analysis, after adjusting for age, sex, and body mass index (BMI), only severe OSAHS, GOLD Ⅲ-Ⅳ grade (FEV 1%pred<50%), and T90>1% were independent risk factors for hypercapnia. Conclusions:OSAHS can increase the risk of hypercapnia in patients with COPD. AHI, lung function injury and T90 are closely related to hypercapnia.

Humans ; Air Pollutants ; Sleep Apnea, Obstructive ; Polysomnography ; Sleep ; Pulmonary Disease, Chronic Obstructive

Objective:To construct a chronic obstructive pulmonary disease (COPD) assessment test (CAT) score prediction model based on a deep network fused with air data, and to explore its significance.Methods:From February 2015 to December 2017, the outdoor environmental monitoring air data near the residential area of the patients with COPD from the Respiratory Outpatient Clinics of Peking University Third Hospital, Peking University People′s Hospital and Beijing Jishuitan Hospital were collected and the daily air pollution exposure of patients was calculated. The daily CAT scores were recorded continuously. The CAT score of the patients in the next week was predicted by fusing the time series algorithm and neural network to establish a model, and the prediction accuracy of the model was compared with that of the long short-term memory model (LSTM), the LSTM-attention model and the autoregressive integrated moving average model (ARIMA).Results:A total of 47 patients with COPD were enrolled and followed up for an average of 381.60 days. The LSTM-convolutional neural networks (CNN)-autoregression (AR) model was constructed by using the collected air data and CAT score, and the root mean square error of the model was 0.85, and the mean absolute error was 0.71. Compared with LSTM, LSTM-attention and ARIMA, the average prediction accuracy was improved by 21.69%.Conclusion:Based on the air data in the environment of COPD patients, the fusion deep network model can predict the CAT score of COPD patients more accurately.

Objective:To explore the differences of clinical laboratory indicators between Kawasaki disease (KD) and systemic juvenile idiopathic arthritis (SJIA), providing objective evidence for diagnosis and differential diagnosis of these diseases.Methods:A total of 41 children patients with KD (KD group) and 33 children patients with SJIA (SJIA group) who received treatment in Huainan Maternal and Child Health Hospital between September 2017 and January 2022 were retrospectively analyzed. An additional 50 healthy children who concurrently received physical examination in the same hospital were included in the control group. Platelet count (PLT), white blood cell count (WBC), and erythrocyte sedimentation rate (ESR) as well as C-reactive protein (CRP), serum procalcitonin (PCT), interleukin-6 (IL-6), interleukin-10 (IL-10), and serum ferritin (SF) levels were compared among groups before treatment.Results:One-way analysis of variance and pairwise q test were performed to compare laboratory indicators among KD, SJIA and control groups. CRP, ESR, SF and IL-6 levels in the KD group were significantly lower than those in the SJIA group [CRP: (57.80 ± 25.23) mg/L vs. (77.72 ± 45.64) mg/L; ESR: (67.02 ± 28.80) mm/h vs. (83.84 ± 47.64) mm/h; SF: (320.21 ± 182.53) μg/L vs. (945.58 ± 604.65) μg/L; IL-6: (50.35 ± 20.54) ng/L vs. (89.35 ± 45.54) ng/L, q = 4.34, 3.42, 11.51, 8.85, all P < 0.05]. IL-10 level in the KD group was significantly higher than that in the SJIA group [(18.52 ± 16.71) ng/L vs. (10.01 ± 3.24) ng/L, q = -5.25, P < 0.05]. WBC, CRP, ESR, PCT, PLT, IL-6, IL-10 and SF in the KD and SJIA groups were significantly higher than those in the control group (all P < 0.05). Conclusion:Detection of CRP, ESR, SF, IL-6, IL-10 in blood can provide objective evidence for the early diagnosis and differential diagnosis of KD and SJIA, thereby reducing the misjudgment of clinical diagnosis.

Objective:To explore the application effect and evaluation of virtual reality technology in oral implant therapy training.Methods:In November 2018, one adult patient (female, 36 years old) with missing right mandibular first molar was treated in the Department of Implantology, School and Hospital of Stomatology, Fujian Medical University. The three-dimensional virtual models of mandible and implant surgery tools were established, and the virtual reality software (Unity 3D 5.5.1) was imported. Combined with the virtual reality head mounted display, a virtual reality training system simulating the dental implant treatment process was independently developed. Ten refresher doctors and 20 graduate students in Department of Implantology, School and Hospital of Stomatology, Fujian Medical University from September 2018 to December 2019 were recruited as the experimental objects (no clinical experience was found). According to the level and seniority of doctors, they were randomly divided into virtual training group and conventional training control group, which made the two groups comparable, with 15 in each group. Subjective scores (including anatomical structure, surgical field of vision, cavity preparation, implant placement and process mastery) were given after the corresponding training in the two groups, and the virtual reality training system was used to test. The mesial and distal direction, buccolingual direction, depth and angle deviation of implants before and after the training were analyzed, and the differences between the two groups were compared.Results:The subjective scores of five dimensions in the virtual training group were significantly higher than those in the conventional training control group ( P<0.05). In the virtual training group, the mesial and distal, buccolingual, depth and angle deviation of implants were (0.73±0.33), (0.78±0.41), (0.61±0.32) mm and 6.66°±3.87°. All of them were significantly lower than those in the control group [(0.85±0.32), (1.12±0.38), (0.89±0.24) mm and 9.68°±3.74°] ( P<0.05). Conclusions:The self-developed virtual reality system of oral implant has good application effect, good operability and predictability. It can be effectively carried out in implant education and training, and it can strengthen skills of doctors, and is conducive to the practical operation.

Objective: To analyze the efficacy of enamel matrix derivative (EMD) combined with bone grafts in the treatment of periodontal osseous defects comparied with that of bone grafts alone by Meta-analysis. Methods: The randomized controlled trials(RCTs) about the efficacy of enamel matrix derivative and bone grafts for the treatment of periodontal osseous defects were collected from Cochrane Library,EMBASE,PubMed,CNKI,Wanfang databases and Google scholar from inception may,2016 by electronic search,scored literatures with the methodological index for non-randomized studies(MINORS) evaluation tool. Revman 5. 3 was used for the Meta-analysis. Results: 5 RCTs articles with 145 cases were included. Meta-analysis showed that: at 6 months of follow-up, PD reduction and CAL gain was found more in test group than in control group(WMD = 0. 40,95％ CI =[0. 01,0. 79],P ＜ 0. 05) and (WMD = 0. 50,95％ CI =[0. 12,0. 88],P ＜ 0. 05) respectively. At 12 months of follow-up,there was no statistical significant difference in PD reduction and CAL gain respectively between the 2 treatments. Conclusion: The combined use of EMD and bone grafts may improve PD reduction and CAL gain in the early stage of convalescence following treatment of periodontal osseous deffects.

Objective To construct a lentiviral vector delivering the Nicastrin (NCT) gene-targeted short hairpin RNA (shRNA) and determine gene-silencing efficiency of the vector in the human immortalized keratinocyte cell line HaCaT,and to construct a NCT gene-silenced HaCaT cell model to lay an experimental foundation for subsequently studying effects of NCT gene silencing on biological behavior of keratinocytes.Methods Three NCT gene-targeted shRNAs were designed and inserted into the pGLV3/ H1/GFP + Puro vector to construct three recombinant plasmids,which were then confirmed by sequencing.Recombinant plasmids combined with lentivirus packaging plasmids were co-transfected into 293T cells to obtain lentivirus particles,and the virus titer was determined.Cultured HaCaT cells were divided into 3 groups:blank group receiving no treatment,negative control group infected with the empty vector LV3-shNC,interference groups infected with lentivirus NCT-shRNA1,-shRNA2,-shRNA3,respectively.Flow cytometry was performed to determine transfection efficiency,and real-time fluorescence-based quantitative PCR (qRT-PCR) and Western blot analysis were conducted to determine efficiency of target gene silencing in HaCaT cells,so as to select the most efficient interference sequence.Results Sequencing analysis indicated that recombinant lentiviral vector NCT-shRNA was constructed successfully.After co-transfection of recombinant plasmids and lentivirus packaging plasmids into 293T cells,the titer of recombinant lentivirus particles was about 109 TU/ml.Flow cytometry showed that the transfection efficiency was greater than 95％.qRT-PCR revealed that the NCT mRNA expression was obviously down-regulated in the interference group compared with the negative control group,and NCT-shRNA1 was the most efficient sequence with interference efficiency being 75％.Western blot analysis showed that the inhibition rate of NCT protein expression was 71.7％ in the shRNA1 group compared with the negative control group.Conclusion The most efficient NCT-shRNA interference sequence is screened out,and the recombinant lentiviral vector NCT-shRNA and an NCT gene-silenced HaCaT cell model are both constructed successfully.

Objective:To evaluate volumetric changes in the upper airway after orthodontic-bimaxillary surgery for the treatment of skeletal class Ⅲ malocclusion.Methods:Literatures about volumetric changes in the upper airway after orthodontic-bimaxillary surgery for the treatment of skeletal class Ⅲ malocclusion were searched from the database:Cochrane library,Embase,PubMed,Web of Science,Wangfang,China Science and Technology Journal Database (VIP),Chinese Biomedical Medicine Database (CBM) and China National Knowledge Infrastructure(CNKI).All the literatures were evaluated by Newcastle-Ottawa Scale(NOS) and analyzed by RevMan 5.3.Results:9 studies with 204 cases about volumetric changes in the upper airway after orthodontic-bimaxillary surgery for the treatment of skeletal Ⅲ malocclusion were included.Meta-analysis showed that after treatment there was no statistical difference about the nasopharyngeal volume change and the total volume change(P＞0.05);there was statistically significant difference about oropharyngeal volume change (P＜0.05).Conclusion:It might be better to consider orthodontic-bimaxillary surgery for skeletal class Ⅲ malocclusion with certain risk factors about OSAHS,but there was still a risk of airway narrow after orthodontic-bimaxillary surgery for skeletal class Ⅲ malocclusion.