Objective:To prepare rabbit polyclonal antibodies against respiratory syncytial virus (RSV) N protein and use them as the detection antibodies to establish a N-ELISA-based method for rapid detection of neutralizing antibodies.Methods:A plasmid of pET30a-N for the expression of RSV N protein was constructed. After purification, the protein was immunized into New Zealand rabbits to prepare polyclonal antibodies, which were used as the detection antibodies. Positive serum samples were diluted and used to neutralize RSV (100 TCID 50/well). Hep-2 cells were inoculated and cultured, and then the cells were fixed with 80% acetone. ELISA was performed to detect RSV N protein in infected cells. When the absorbance value of a well was below the cut-off value, it was regarded as the positive well in the neutralization test. The highest dilution of a positive well serum was the neutralizing antibody titer. After optimizting the antibody dilution, detection time, cell density and the duration of neutralization, the method for neutralizing antibody detection was established based on N-ELISA. The established method was verified by analyzing the influences of different cell generations and edge effects, and calculating the accuracy, repeatability and precision. The correlation between the established method and microneutralization method was analyzed by detecting human RSV IgG-positive serum. Results:The plasmid pET30a-N was successfully constructed, and the expressed N protein showed high purity and good specificity. After the third immunization, the antibody titer in rabbit serum was 1∶51 200, and the antibodies could specifically bind to RSV. The prepared rabbit anti-RSV N polyclonal antibodies had a titer of 1∶51 200, and showed good specificity. The neutralizing antibodies could be detected on day 4 with the established method, and the duration of neutralization was shortened to 30 min. Cell generations and the position of wells in the 96-well plate (edge well and non-edge well) had no significant effect on the method, and the repeatability, precision and accuracy of the method were good. In the detection of 64 RSV IgG-positive human serum samples by the established method and microneutralization method, the correlation coefficient was 0.929 6, indicating a good positive correlation between the two methods.Conclusions:A N-ELISA-based method for rapid neutralizing antibody detection is successfully established, which can be used to evaluate the serum antibody level after RSV vaccination.

The importance of evaluating the oxygen supply system of the medical aircraft was introduced.With considerations on the characteristics of the oxygen supply system of the medical aircraft during its development and application,an oxygen supply system effectiveness evaluation method was proposed based on the analytic hierarchy process and the experience of experts in the field of medical aircraft,which involved in seven evaluation indexes of total oxygen supply,pipeline airtight-ness,single-nozzle flow adjustment characteristics,single-nozzle outlet pressure adjustment characteristics,disassembly and assembly,mechanical operation and fixation ability.The effectiveness evaluation method proposed was of significance for accurately grasping the changes in the performance of the oxygen supply system.References were provided for the ground maintenance of the oxygen supply system of the medical aircraft.[Chinese Medical Equipment Journal,2024,45(1):89-92]

Objective To explore the effect of Huangqi Yanghe Decoction on wound healing of diabetic foot ulcer(DFU)rats based on phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/nuclear factor-κB(NF-κB)signal pathway.Methods DFU rat model was constructed,and 48 rats successfully modeled were randomly divided into the model group,the Huangqi Yanghe Decoction low(8.5 g/kg)group,the Huangqi Yanghe Decoction high(17 g/kg)dose group and the Huangqi Yanghe Decoction high dose(17 g/kg)+LY294002(PI3K/AKT pathway inhibitor,0.3 mg/kg)group.There were 12 rats in each group.Another 12 rats were selected as the control group.Rats in each group were given corresponding drug intervention for 4 weeks.After the 14th and 28th day-administration,the general state and wound changes of rats were observed,and the wound healing rate was calculated.The fasting blood glucose(FBG)level of rats was measured,and the percutaneous partial pressure of oxygen(TcpO2)of tissue around the wound was detected.Serum levels of vascular endothelial growth factor(VEGF),hypoxia inducible factor-1α(HIF-1α),C-reactive protein(CRP)and interleukin(IL)-6 were determined by enzyme linked immunosorbent assay.Histopathological changes of the wound were observed by hematoxylin-eosin staining.Immunohistochemical staining was used to measure the microvascular density of rat wound tissue.The protein expression levels of PI3K,phosphorylated PI3K(p-PI3K),AKT,phosphorylated AKT(p-AKT),NF-κB p65,phosphorylated NF-κB p65(p-NF-κB p65)and NF-κB inhibitory protein α(IκB-α)in rat wound tissue were determined by Western blot assay.Results Rats in the control group had smooth hair color,normal diet,drinking water and excretion,more active,wound healing fast,less inflammatory reaction in wound tissue,and there were more new blood vessels.Fibroblasts and collagen matrix were abundant in granulation tissue.In the model group,the fur color of rats was dull and matte,and the activity was reduced.The symptoms of polydipsia,polyphagia and polyuria were appeared in the model group,the wound color was dark,and edema and ulcer appeared in the surrounding tissue,a large number of inflammatory cells infiltrated in the wound tissue,accompanied by tissue necrosis and exudation,fewer neovascularization and fibroblasts were observed.Wound healing rate,TcpO2 in wound surrounding tissue,serum VEGF,HIF-1α,microvascular density,p-PI3K,p-AKT and IκB-α protein expression levels in wound tissue were decreased,and FBG,serum CRP,IL-6,p-NF-κB p65 protein expression in wound tissue were increased(P＜0.05).Compared with the model group,the state of rats was gradually improved in the Huangqi Yanghe Decoction low and high dose groups,and the lesion degree of wound tissue was reduced successively,wound healing rate,TcpO2 in wound surrounding tissue,serum VEGF,HIF-1α,microvascular density,p-PI3K,p-AKT and IκB-α protein expression levels in wound tissue were increased in turn(P＜0.05).The FBG,serum CRP,IL-6 and p-NF-κB p65 protein expression in wound tissue were decreased in turn(P＜0.05).LY294002 could partially reverse the therapeutic effect of high-dose Huangqi Yanghe Decoction on DFU rats(P＜0.05).Conclusion Huangqi Yanghe Decoction can regulate PI3K/AKT/NF-κB pathway,inhibit inflammatory response in DFU rats,promote angiogenesis and thus promote wound healing.

Objective To explore the modal testing method for the three-axis manned centrifuge under elastic boundary conditions with considerations on its complicated structure and high rotational inertia.Methods Modal testing was carried out with a three-axis manned centrifuge under elastic boundary conditions as the subject and a force hammer as the excitation source according to GJB 2706A-2008 Modal tests method for spacecraft and GB/T 11349.3-1992 Experimental determination of mechnical mobility measurements using impact excitation.Four times of hammering were carried out at each excitation position,and the data of the four times of hammering underwent linear average computation.Data acquisition was implemented with a three-axis accelerometer and a 64-channel data collector,and the modal data were analyzed using a frequency response function based on the Test.Lab modal test and analysis software.Results The coherence coefficient of the excitation signal was not lower than 0.8 in the 30 Hz band;the first three orders of the system's intrinsic vibrations were all torsional vibrations,with the frequencies of 9.15,15.66 and 19.22 Hz,respectively;the first order frequency of the system was about 9.15 Hz for both Z18 and Z21 excitation positions,and each of the second and third order frequencies similar situations were observed for also had a roughly equal value for the two excitation positions.Conclusion The force hammer testing method is applicable for the modal testing of the three-axis manned centrifuge,ensuring equipment safety and subject comfort.Referen-ces are provided for the following structural optimization design.[Chinese Medical Equipment Journal,2024,45(8):38-43]

Objective To analyze the risk factors and survival status of Epstein-Barr virus(EBV)infection in pa-tients with aplastic anemia(AA)after haploid allogeneic hematopoietic stem cell transplantation(Haplo-HSCT).Methods Clinical data of 78 AA patients who underwent Haplo-HSCT in the hematology department of a hospital from January 1,2019 to October 31,2022 were analyzed retrospectively.The occurrence and onset time of EBV viremia,EBV-related diseases(EBV diseases),and post-transplant lymphoproliferative disorders(PTLD)were ob-served,risk factors and survival status were analyzed.Results Among the 78 patients,38 were males and 40 were females,with a median age of 33(9-56)years old;53 patients experienced EBV reactivation,with a total inci-dence of 67.9％,and the median time for EBV reactivation was 33(13,416)days after transplantation.Among pa-tients with EBV reactivation,49 cases(62.8％)were simple EBV viremia,2 cases(2.6％)were possible EBV di-seases,and 2 cases(2.6％)were already confirmed EBV diseases(PTLD).Univariate analysis showed that age 1＜40 years old at the time of transplantation,umbilical cord blood infusion,occurrence of acute graft-versus-host disease(aGVHD)after transplantation,and concurrent cytomegalovirus(CMV)infection were independent risk fac-tors for EBV reactivation in AA patients after Haplo-HSCT.Multivariate analysis showed that concurrent CMV in-fection was an independent risk factor for EBV reactivation in A A patients after Haplo-HSCT(P=0.048).Ritu-ximab intervention before stem cell reinfusion was a factor affecting the duration of EBV reactivation(P＜0.05).The mortality of EBV viremia,EBV diseases,and PTLD alone were 8.2％,50.0％,and 100％,respectively.The 2-year overall survival rate of patients with and without EBV reactivation were 85.3％,and 90.7％,respectively,difference was not statistically significant(P=0.897).However,patients treated with rituximab had 2-year lower survival rate than those who did not use it,with a statistically significant difference(P=0.046).Conclusion EBV reactivation is one of the serious complications in AA patients after Haplo-HSCT,which affects the prognosis and survival of patients.

Objective To understand the prevalence characteristics of influenza and changes of influenza virus strains,and provide reference for the prevention and control of influenza in the province.Methods Surveillance da-ta about influenza in Hunan Province from 2014 to 2023 were exported from China Influenza Surveillance Informa-tion System.Differences in the percentage of influenza-like illness(ILI)cases(percentage of influenza-like cases[ILI％]in outpatient and emergency department visits)among different years and different populations,as well as the positive rate of influenza virus in ILI specimens were compared.Results From 2014 to 2023,over 2.65 million cases of ILI were reported,with an ILI％of 4.70％.ILI％among different years presented statistically significant differences(P＜0.001).People aged 0-14 years old were the main population with ILI,accounting for 82.90％.The positive rate of influenza virus in ILI specimens was 14.14％,the positive rate of influenza virus among diffe-rent years and age groups were both significantly different(both P＜0.001).The main prevalent influenza strains from 2014 to 2023 included types A(H1N1),A(H3N2),B(Victoria),and B(Yamagata),alternating among di-fferent years.However,type B(Yamagata)strains were not detected from 2020 to 2023.There were basically two influenza prevalence seasons every year,namely winter-spring and summer.Conclusion People＜15 years old are the main population of influenza,and the prevalence peaks are in winter-spring and summer.From 2021 to 2023,the prevalence alternates mainly among 3 types:A(H1N1),A(H3N2),and B(Victoria).

COVID-19 has been prevalent for three years. The virulence of SARS-CoV-2 is weaken as it mutates continuously. However, elderly patients, especially those with underlying diseases, are still at high risk of developing severe infections. With the continuous study of the molecular structure and pathogenic mechanism of SARS-CoV-2, antiviral drugs for COVID-19 have been successively marketed, and these anti-SARS-CoV-2 drugs can effectively reduce the severe rate and mortality of elderly patients. This article reviews the mechanism, clinical medication regimens, drug interactions and adverse reactions of five small molecule antiviral drugs currently approved for marketing in China, so as to provide advice for the clinical rational use of anti-SARS-CoV-2 in the elderly.

Objective To develop aeromedical training data management software for manned centrifuges to realize comprehensive management of multi-type and multi-dimensional training information during pilot manned centrifuge training.Methods A piece of aeromedical training data management software for manned centrifuges was designed with micro-service pattern,programmed with C# language and developed with model-view-controller mode,which realized data interaction and time synchronization with other systems through multi-threading technology.There were eight functional modules involved in the system developed for login management,training management,training program management,pilot information management,trainer information management,pilot training data management,statistical query and system management.Results The software developed implemented information automatic acquisition and unified management of physiological parameter data,audio and video data and operating load curve,which enhanced the efficiency of training and the informatization level of training data statistics and analysis.Conclusion The software developed improves the informatization level of pilot manned centrifuge aeromedical training data management and provides support for aeromedical training.[Chinese Medical Equipment Journal,2023,44(11):39-44]

This study was aimed at understanding the genome-wide characterization and variations for three imported novel coronavirus(SARS-CoV-2)strains from different sources in the same period in Jinan at the viral genome level,to provide a sci-entific basis for further improving the prevention and control of COVID-19 outbreaks at Jinan port.We selected nasal and pha-ryngeal swab samples from three cases of imported asymptomatic COVID-19infectionat Jinan port;performed second-genera-tion whole-genome sequencing;and analyzed the variant loci and homology withvarious bioinformatics software.The whole ge-nome sequence of SARS-CoV-2 was successfully obtained from three samples of asymptomatic infected cases,and had full lengths ranging from 29 835 bp to 29 844 bp.Pangolin typing results indicated that the genotypes of the three samples were O-micron BQ.1,BQ.1.1,and BQ.1.12.Compared with the original Wuhan strain,the three samples produced mutations at 77,80,and 78 base sites,respectively,involving 60-63 non-synonymous mutations,mainly in the S and ORF1ab genes.Omicron BQ.1 is an imported variant of the SARS-CoV-2 virus and was detected for the first time at Jinan port.From a molecular biolo-gy perspective,this study provides a theoretical basis for the source tracing and prevention and control of COVID-19 at theport.

Objective:To compare the short-term curative effects between 3 fixations of the tibial end with an interface screw, an interface screw + a portal nail and an interface screw + a knotless rivet in reconstruction of the anterior cruciate ligament (ACL).Methods:A retrospective study was conducted to analyze the data of 150 patients who had undergone reconstruction surgery for ACL injury at Department of Orthopaedics, Jinling Clinical Medical College, Nanjing Medical University from January 2019 to December 2021. The patients were divided into 3 groups according to their different fixations of the tibial end. In group A of 51 cases subjected to fixation of the tibial end with an interface screw, there were 40 males and 11 females with a mean age of (29.8±10.6) years. In group B of 55 cases whose tibial end was fixated with an interface screw + a portal nail, there were 47 males and 8 females with a mean age of (28.6±6.9) years. In group C of 44 cases whose tibial end was fixated with an interface screw + a knotless rivet, there were 39 males and 5 females with a mean age of (28.6±8.1) years. The 3 groups were compared in terms of International Knee Documentation Committee (IKDC) scoring and Lysholm knee function scoring at 12 and 48 weeks after operation, incidence of local pain at 4 weeks after operation, and stability of the knee at 48 weeks after operation.Results:There was no significant difference in the preoperative general data or follow-up time between the 3 groups, indicating comparability ( P>0.05). At 12 weeks after surgery, in Group B and Group C, the IKDC scores [(74.27±3.32) and (76.48±3.83) points] and Lysholm knee joint scores [(77.65±3.14) and (79.75±5.39) points] were significantly better than those in Group A [(69.73±6.04) and (71.63±3.36) points] ( P<0.05). However, there was no statistically significant difference in the above scores among the 3 groups at 48 weeks after surgery ( P>0.05). The incidence of local pain at the tibial end in group B (9.1%, 5/55) was significantly higher than that in group A (0, 0/51) and group C (2.3%, 1/44) at 4 weeks after surgery, and the results of the anterior drawer test in group A (36 negative cases, 14 cases of grade Ⅰ, and 1 case of grade Ⅱ) were significantly worse than those in group B (50 negative cases, and 5 cases of grade Ⅰ) and group C (40 negative cases, and 4 cases of grade Ⅰ) at 48 weeks after surgery ( P<0.05). Conclusions:In ACL reconstruction, all the 3 fixations of the tibial end can achieve fine short-term curative effects. Fixation with an interface screw + a knotless rivet may lead to a lower rate of ligament relaxation and a higher score of early knee function than fixation with an interface screw, and a lower incidence of local pain at the tibial end than fixation with an interface screw + a portal nail.