Objective To prepare a variety of quality control(QC)materials for SARS-CoV-2 variants as an addition to the conven-tional SARS-CoV-2 nucleic acid QC products for the laboratory detection of mutant strains by optimizing the preparation and purification process of MS2 phage virus-like particle(VLP)technique,and evaluate their performances.Methods The typical mutation sequence fragments or full length S genes were designed and synthesized according to the genomic information of SARS-CoV-2 variants.Then,they were inserted into the downstream of maturase gene,coat protein and the pac-site of MS2 phage to construct a series of recombi-nant expression vectors.After induced by the prokaryotic expression system,the VLP products were purified through the polyethylenei-mine precipitation,ultrafiltration,nuclease digestion,and gel filtration chromatography.The obtained VLP were validated by the nucle-ic acid electrophoresis,protein electrophoresis,protein concentration determination,and fluorescence PCR,and their performances such as nucleic acid residue and stability were also evaluated.Results A total of 10 kinds of VLP containing the targeted sequences of the gene to be tested were prepared.The length of the foreign sequence wrapped in them ranged from 297 bp to 3 822 bp,which could be combined into a variety of QC materials for the mutation detection of different SARS-CoV-2 variants.The prepared VLP QC materials could not be effectively amplified without nucleic acid extraction or reverse transcription steps during the routine nucleic acid detection.The simulated QC samples remained stable after repeated freeze-thaw cycles.They could be stored stably for 2 months at 25 ℃ and 4 weeks at 37 ℃.Conclusion The established preparation and combined purification process of VLP QC materials can encapsulate vari-ous exogenous nucleic acid sequences with different lengths into the viral coat protein to form VLP,with high production efficiency.The VLP QC products prepared by the above process have stable performance and almost no residual exogenous nucleic acid,which can ef-fectively meet clinical requirements and ensure the quality of laboratory testing.

Objective To prepare a variety of quality control(QC)materials for SARS-CoV-2 variants as an addition to the conven-tional SARS-CoV-2 nucleic acid QC products for the laboratory detection of mutant strains by optimizing the preparation and purification process of MS2 phage virus-like particle(VLP)technique,and evaluate their performances.Methods The typical mutation sequence fragments or full length S genes were designed and synthesized according to the genomic information of SARS-CoV-2 variants.Then,they were inserted into the downstream of maturase gene,coat protein and the pac-site of MS2 phage to construct a series of recombi-nant expression vectors.After induced by the prokaryotic expression system,the VLP products were purified through the polyethylenei-mine precipitation,ultrafiltration,nuclease digestion,and gel filtration chromatography.The obtained VLP were validated by the nucle-ic acid electrophoresis,protein electrophoresis,protein concentration determination,and fluorescence PCR,and their performances such as nucleic acid residue and stability were also evaluated.Results A total of 10 kinds of VLP containing the targeted sequences of the gene to be tested were prepared.The length of the foreign sequence wrapped in them ranged from 297 bp to 3 822 bp,which could be combined into a variety of QC materials for the mutation detection of different SARS-CoV-2 variants.The prepared VLP QC materials could not be effectively amplified without nucleic acid extraction or reverse transcription steps during the routine nucleic acid detection.The simulated QC samples remained stable after repeated freeze-thaw cycles.They could be stored stably for 2 months at 25 ℃ and 4 weeks at 37 ℃.Conclusion The established preparation and combined purification process of VLP QC materials can encapsulate vari-ous exogenous nucleic acid sequences with different lengths into the viral coat protein to form VLP,with high production efficiency.The VLP QC products prepared by the above process have stable performance and almost no residual exogenous nucleic acid,which can ef-fectively meet clinical requirements and ensure the quality of laboratory testing.

Objective:Middle ear cholesteatoma is a common otolaryngological disease, and traditional diagnostic methods have certain limitations. This study aims to construct a computer-aided diagnosis model for middle ear cholesteatoma based on integrated convolutional neural networks (CNNs) to improve diagnostic accuracy and efficiency.Methods:Firstly, Data were collected from patients who visited the Department of Otorhinolaryngology Head and Neck Surgery at the First People′s Hospital of Yinchuan between January 2020 and December 2021. 8 000 temporal bone CT images were collected, including 5 000 images diagnosed pathologically as middle ear cholesteatoma and 3 000 normal images. A five-fold cross-validation method was used to divide the dataset into training and testing sets. Next, a transfer learning approach was used to initialize model parameters, and the AlexNet, GoogleNet, and ResNet networks were pre-trained to extract deep features from the images. Then, the Softmax classification algorithm was applied to classify the features, resulting in three independent classifiers. These classifiers were combined using an ensemble learning method with a weighted voting approach to obtain the final diagnostic results. Finally, the model was evaluated by comparing the ensemble classifier with individual classifiers to assess its accuracy, precision, sensitivity, specificity, and diagnostic time, and a comparison with low-mid-and high-experience physician groups was conducted to comprehensively evaluate the model′s diagnostic performance.Results:The experimental results showed that the model achieved an accuracy of 88.8%(178/200), precision of 92.9%,(112/120) sensitivity of 89.8%(108/120), and specificity of 88.1%(70/80). The average diagnostic time for individual patient temporal bone CT images was reduced to 2-3 seconds. Compared to the diagnostic results from low-mid-and high-experience physician groups, the model demonstrated significant advantages and effectively assisted clinicians in making rapid and accurate middle ear cholesteatoma diagnoses.Conclusion:The proposed middle ear cholesteatoma diagnostic model based on integrated convolutional neural networks exhibits high recognition accuracy and rapid diagnostic speed, significantly improving clinical diagnostic efficiency, especially in early screening and auxiliary diagnosis, making it of considerable value in clinical practice.

Objective:Middle ear cholesteatoma is a common otolaryngological disease, and traditional diagnostic methods have certain limitations. This study aims to construct a computer-aided diagnosis model for middle ear cholesteatoma based on integrated convolutional neural networks (CNNs) to improve diagnostic accuracy and efficiency.Methods:Firstly, Data were collected from patients who visited the Department of Otorhinolaryngology Head and Neck Surgery at the First People′s Hospital of Yinchuan between January 2020 and December 2021. 8 000 temporal bone CT images were collected, including 5 000 images diagnosed pathologically as middle ear cholesteatoma and 3 000 normal images. A five-fold cross-validation method was used to divide the dataset into training and testing sets. Next, a transfer learning approach was used to initialize model parameters, and the AlexNet, GoogleNet, and ResNet networks were pre-trained to extract deep features from the images. Then, the Softmax classification algorithm was applied to classify the features, resulting in three independent classifiers. These classifiers were combined using an ensemble learning method with a weighted voting approach to obtain the final diagnostic results. Finally, the model was evaluated by comparing the ensemble classifier with individual classifiers to assess its accuracy, precision, sensitivity, specificity, and diagnostic time, and a comparison with low-mid-and high-experience physician groups was conducted to comprehensively evaluate the model′s diagnostic performance.Results:The experimental results showed that the model achieved an accuracy of 88.8%(178/200), precision of 92.9%,(112/120) sensitivity of 89.8%(108/120), and specificity of 88.1%(70/80). The average diagnostic time for individual patient temporal bone CT images was reduced to 2-3 seconds. Compared to the diagnostic results from low-mid-and high-experience physician groups, the model demonstrated significant advantages and effectively assisted clinicians in making rapid and accurate middle ear cholesteatoma diagnoses.Conclusion:The proposed middle ear cholesteatoma diagnostic model based on integrated convolutional neural networks exhibits high recognition accuracy and rapid diagnostic speed, significantly improving clinical diagnostic efficiency, especially in early screening and auxiliary diagnosis, making it of considerable value in clinical practice.

Objective:To explore the cutting scheme and clinical application effects of ultrathin thoracodorsal artery perforator flap assisted by color Doppler ultrasound.Methods:This study was a retrospective historical control study. From February 2017 to October 2019, 20 patients who were admitted to the Third Department of Orthopedics of Xingtai General Hospital of North China Medical and Health Group (hereinafter referred to as our department), met the inclusion criteria, and underwent repair of skin and soft tissue defects of extremities with ultrathin thoracodorsal artery perforator flap designed and harvested based on the surgeon's clinical experience were selected as control group, including 16 males and 4 females, aged (37±5) years. From November 2019 to December 2022, 21 patients who were admitted to our department, met the inclusion criteria, and underwent repair of skin and soft tissue defects of extremities with ultrathin thoracodorsal artery perforator flap designed and harvested under the assistance of color Doppler ultrasound were selected as ultrasound-assisted group, including 15 males and 6 females, aged (38±6) years. After debridement, the area of skin and soft tissue defects of extremities ranged 5.0 cm×4.0 cm to 19.0 cm×8.0 cm, and the area of thoracodorsal artery perforator flaps ranged 6.0 cm×5.0 cm to 20.0 cm×9.0 cm. The wounds in flap donor sites were closed directly. For patients in ultrasound-assisted group, the time and cost required for color Doppler ultrasound examination were recorded, and the number, type, and location of thoracodorsal artery perforator vessels detected by preoperative color Doppler ultrasound were compared with those of intraoperative actual detection. The time required for complete flap harvest of patients in 2 groups was recorded. On postoperative day (POD) 1, 3, 5, 7, and 14, the blood perfusion of flaps in the 2 groups of patients was assessed using a flap perfusion assessment scale. On POD 14, flap survival of patients in 2 groups was observed, and the percentage of flap survival area was calculated. In postoperative 6 months, satisfaction of patients with the treatment outcome in the 2 groups was assessed using 5-grade Likert scale, and the satisfaction rate was calculated.Results:For patients in ultrasound-assisted group, the time required for preoperative color Doppler ultrasound examination was (10.5±2.3) min, and the cost was 120 yuan; 21 thoracodorsal artery perforator vessels were detected and marked using preoperative color Doppler ultrasound, including 8 (38.10%) type 1 perforator vessels, 10 (47.62%) type 2 perforator vessels, and 3 (14.29%) type 3 perforator vessels; the number, type, and location of thoracodorsal artery perforator vessels detected preoperatively were consistent with those detected intraoperatively. The time required for complete flap harvest of patients in ultrasound-assisted group was (41±10) min, which was significantly shorter than (63±12) min in control group ( t=6.32, P<0.05). On POD 1, 3, 5, 7, and 14, the blood perfusion scores of flaps of patients in ultrasound-assisted group were significantly better than those in control group (with t values of 6.67, 7.48, 8.03, 8.75, and 7.99, respectively P<0.05). On POD 14, only one patient in ultrasound-assisted group had partial flap necrosis and 6 patients in control group had complete or partial necrosis of the flap; the percentage of flap survival area of patients in ultrasound-assisted group was (99±8)%, which was significantly higher than (87±8)% in control group ( t=4.57, P<0.05). In postoperative 6 months, there was no significant difference in the satisfaction rate of patients with the treatment outcome between the two groups ( P>0.05). Conclusions:Preoperative color Doppler ultrasound is highly accurate in detecting the number, type, and location of perforator vessels. The cutting scheme of ultrathin thoracodorsal artery perforator flaps can be designed according to the different types of perforator vessels, with shorted flap cutting time and improved flap survival rate.

Objective To investigate the effects of pterostilbene on human colon cancer LoVo cells and study the regulatory mechanism of nuclear factor E2-related factor 2(Nrf2)in the process of pterostilbene acting on LoVo cells.Methods LoVo cells were treated with different concentrations(5,10,20,40,60,80,100 panol/L)of pterostilbene.Cell viability,migration,invasion,and apoptosis were examined by CCK-8,scratch,Tran-swell,and TUNEL assays,respectively.The mitochondrial membrane potential was measured by the mitochon-drial membrane potential assay kit with JC-1.The reactive oxygen species level was measured by 2',7'-dichlo-rofluorescein diacetate.The protein levels of Nrf2,phosphorylated Nrf2,heme oxygenase 1,and apoptotic pro-teins(Bcl2 and Bax)were determined by Western blotting.In addition,cell viability,Nrf2 expression,and ap-optosis rate were determined after co-application of the Nrf2-specific agonist sulforaphane.Results Compared with the control group,40,60,80,100 μmol/L pterostilbene reduced the viability of LoVo cells(P=0.014,P＜0.001,P＜0.001,P＜0.001).Pterostilbene at 5,10,20 μmol/L did not show effects on cell viability but inhibited cell migration(P=0.008,P＜0.001,P＜0.001)and invasion(all P＜0.001).Pterostilbene at 40,60,80 μmol/L increased apoptosis(P=0.014,P＜0.001,P＜0.001),promoted mitochondrial membrane potential depolarization(P=0.026,P＜0.001,P＜0.001)and reactive oxygen species accumula-tion(all P＜0.001),and down-regulated the expression of phosphorylated Nrf2(P=0.030,P＜0.001,P＜0.001),heme oxygenase 1(P=0.015,P＜0.001,P＜0.001),and Bc12(P=0.039,P＜0.001,P＜0.001)in LoVo cells.Pterostilbene at 60,80 μmol/L down-regulated Nrf2 expression(P=0.001,P＜0.001)and up-regulated Bax expression(both P＜0.001).The application of sulforaphane reversed the effects of pterostilbene on cell viability(P＜0.001),apoptosis(P＜0.001),and Nrf2 expression(P=0.022).Conclusion Pterostilbene is a compound that can effectively inhibit colon cancer cells by inhibiting the Nrf2 pathway.

Objective To analyze the infection status of Mycoplasma pneumoniae(MP)in the First Affilia-ted Hospital of Shandong First Medical University(the hospital)from 2019 to 2023 and explore the related influencing factors.Methods Basic admission information,test results,and related diagnostic results of 16 465 MP positive patients admitted to the hospital were collected,and the distribution characteristics of the number and disease types of MP positive patients in the hospital were analyzed.Results The positive rate of MP from high to low in the 5 years was in the years of 2021,2019,2020,2022,2023(P＜0.05).The proportion of MP positive cases in outpatient department from high to low was in the years of 2023,2021,2022,2019 and 2020(P＜0.05).Incidence was higher in spring and winter.In 5 years,the positivity rate of MP in respiratory tract infection patients was slightly higher in males than in females,the proportions of males in 2020 and 2022 were higher than those in 2019 and 2021(P＜0.05),and the proportions of males in 2019,2020,and 2022 were higher than that in 2023(P＜0.05).The age groups of MP infected patients were mainly concentrated in ado-lescents and infants under 14 years old.The positive results of patients in the 5 years were mainly distributed in titers of 1∶40,1∶80,and＞1∶160.There was no statistically significant difference in the proportion of positive results with MP total antibody≥1∶160 detected(P＞0.05).The top 5 clinical diagnoses of MP in-fected patients in thed hospital were fever,acute bronchitis,bronchopneumonia,chronic bronchitis,and pneu-monia,and the difference in the proportion of diagnostic results was statistically significant(P＜0.05).Conclu-sion This study clarifies the infection status of MP in the hospital from 2019 to 2023,and analyzes the impact of factors such as season,gender,and age on MP infection,which is of great significance for the prevention and control of respiratory infectious diseases in the hospital.

Objective To investigate the impact of not using drainage on clinical outcomes after arthroscopic autologous semitendinosus tendon reconstruction with anterior cruciate ligament reconstruction.Methods From March 2022 to June 2023,59 patients undergoing arthroscopic autologous semitendinosus tendon reconstruction with anterior cruciate ligament reconstruction in Lincang People's Hospital were collected and randomly divided into the non-drainage group consisting of 29 cases(observation group)and the 24-hour drainage group consisting of 30 cases(control group).The pain levels of the two groups of patients were recorded on the 1st,3rd,7th,14th,and 30th day after the surgery by using a visual analog scale.Additionally,the knee joint range of motion,length of hospital stay,and occurrence of postoperative complications were monitored.The circumference of the thigh was measured before and after the surgery,and the difference was calculated.Results Repeated measures analysis of variance revealed that there were statistically significant within-subject differences in pain ratings,thigh circumference,and knee joint range of motion(P<0.05),but no statistically significant between-subject differences(P>0.05).Independent samples t-tests showed that on the first day after the surgery,the observation group had lower pain ratings(P<0.001),and higher thigh circumference and knee joint range of motion compared to the control group(P<0.05).There were no statistically significant differences in pain ratings,knee joint range of motion,and thigh circumference between the two groups at the remaining follow-up times(P>0.05);The observation group had a shorter hospital stay than the control group(P<0.001);Both groups of patients had no complications such as lower limb nerve damage,deep vein thrombosis,knee joint infection,or hematomas requiring puncture and aspiration.Conclusion In the early postoperative period following arthroscopic autologous hamstring tendon reconstruction of the anterior cruciate ligament,the omission of drainage does not affect the clinical outcomes in terms of pain,knee joint mobility,and thigh circumference.Moreover,omitting drainage reduces the level of pain experienced by patients on the first day after the surgery,improves the knee joint mobility,and decreases the length of hospital stay.Therefore,in arthroscopic autologous hamstring tendon reconstruction of the anterior cruciate ligament,it is not recommended to routinely use drainage for preventive purposes.

Objective:To explore the clinical application of three-dimensional CT angiography (3D-CTA) in repair of limb wounds with free lateral thoracic perforator flaps.Methods:A retrospective study was conducted to analyze the clinical data of 61 patients with limb soft tissue defects who had been treated at The Third Department of Orthopedics, Xingtai General Hospital of North China Medical and Health Group from January 2018 to September 2022. There were 37 males and 24 females with an age of (43.9±12.0) years. Thirty-three left and 28 right sides were injured. Soft tissue defects ranged from 4.0 cm × 3.0 cm to 17.0 cm × 8.0 cm, and flap areas from 5.0 cm × 4.0 cm to 18.0 cm × 9.0 cm. The patients were divided into 2 groups according to the different preoperative vascular exploration methods: an ultrasound group of 30 cases subjected to ultrasound Doppler examination and a 3D-CTA group of 31 cases subjected to 3D-CTA examination. The preoperative findings were compared with those of intraoperative exploration in the 2 groups. The operation time, flap survival rate, patient satisfaction with trauma repair, sensory recovery of the flap area, and the excellent and good rate of the donor area were also compared between the 2 groups.Results:The differences in preoperative general data between the 2 groups were not statistically significant, indicating the 2 groups were comparable ( P>0.05). In the ultrasound group, the inraoperative classification of the lateral thoracic perforator flaps showed a low concordance with preoperative classification (Kappa coefficient of 0.104, P=0.088). In the 3D-CTA group, the classification of lateral thoracic perforator flaps was consistent with the preoperative 3D-CTA examination (Kappa coefficient of 1.00, P<0.001). The preoperative measurements in the 3D-CTA group found that the diameter at the origin of the lateral thoracic artery was (1.2±0.3) mm, the vascular pedicle length (8.1±2.1) cm, and the diameter at the perforator exit (0.6±0.2) mm; the preoperative surface positioning at the perforator exit found that the perforator exit was (1.6±0.3) cm above the horizontal line of the subscapular angle and (5.3±1.4) cm outside the vertical line of the subscapular angle. These measurements were similar to the intraoperative ones [(1.1±0.3) mm, (8.3±2.4) cm, (0.7±0.2) mm, (1.5±0.4) cm, and (5.2±1.5) cm], showing no significant differences ( P>0.05). In contrast, the preoperative measurements of the above indexes in the ultrasound group did not coincide with the actual intraoperative measurements, and the differences were all statistically significant ( P<0.05). The operation time, flap survival rate, rate of patient satisfaction with wound repair, rate of sensory recovery in the flap area, and the excellence and good rate of the donor area in the 3D-CTA group were (52.9±16.7) min, 100.0% (31/31), 96.8% (30/31), 83.9% (26/31), and 87.1% (27/31), respectively, which were significantly better than those in the ultrasound group [(76.3±21.4) min, 86.7% (26/30), 76.7% (23/30), 60.0% (18/30), 63.3% (20/30)] ( P<0.05). Conclusions:As preoperative 3D-CTA examination can clarify the types and anatomical characteristics of the lateral thoracic artery and its perforators, it helps the design and harvest of the lateral thoracic perforator flaps. Compared with the ultrasound Doppler examination, preoperative 3D-CTA examination shortens operation time, raises survival rate of the flaps, and facilitates recovery of the appearance and function of the limb wounds, and leads to little impact on the donor site.

Objective:To comprehensively search, analyze and integrate the best evidence on environmental factors for the prevention and management of myopia in children and adolescents, to provide reference for the formulation of scientific and complete myopia prevention and management programs.Methods:A comprehensive search about evidence on environmental factors prevention and management of myopia in children and adolescents was conducted in following databases: UpToDate, BMJ Best Practice, Cochrane Library, JBI Evidence-Based Health Care Center Database, Chinese Medical Ace Base, China Association of Chinese Medicine, Chinese Medical Association, American Academy of Ophthalmology, International Myopia Society, European Society of Ophthalmology, International Agency for the Prevention of Blindness, Brien Holden Vision Research Center, PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Wanfang, etc. Research types included guidelines, expert consensus, systematic review/Meta-analysis, evidence summary, best clinical practice.Results:A total of 23 articles were included, including 6 guidelines, 3 expert consensus articles and 14 systematic reviews. Evidence summarized 27 items from the following 4 aspects: prevention and management purpose, risk assessment, environmental prevention and management measures and health education.Conclusions:This study summarized the best evidence on environmental factors to prevent and manage myopia in children and adolescents. When the evidence is applied, appropriate environmental prevention and management measures should be selected to prevent and control the onset and progression of myopia in children and adolescents, based on the actual situation, to promote evidence-based practice.