Objective To investigate the effect and potential mechanism of chimeric antigen receptor(CAR)-natural killer(NK)cell therapy on the growth of gastric cancer cells and xenograft tumors.Methods Cell experiments:The gastric cancer cell lines of SGC7901 and MGC803 were co-cultured with CAR-NK cells as the CAR-NK group,the NK cells were co-cultured with SGC7901 and MGC803 cells as the NK group,respectively.The mRNA levels of PD-1 and PD-L1 in both groups were detected by RT-qPCR.The cell proliferation ability was assessed using EdU staining and CCK-8 assay.The cell migration and invasion abilities were detected by Transwell assay.The change of cell cycle was detected by flow cytometry.The expression of PD-1 and PD-L1 proteins in cells was detected by Western blot.Animal experiments:Mice were established model of xenograft tumors and divided into the blank control group(inoculated with routinely cultured SGC7901 cells),NK treatment group(inoculated SGC7901 cells combined NK cells),CAR-NK treatment group(inoculated SGC7901 cells combined CAR-NK cells),CAR-NK+rhPD-1 treatment group(inoculated SGC7901 cells combined CAR-NK cells,with intraperitoneal injection of 5 mg/kg rhPD-1 concurrently),and CAR-NK+rhPD-L1 treatment group(inoculated SGC7901 cells combined CAR-NK cells,with intraperitoneal injection of 5 mg/kg rhPD-L1 concurrently),with 5 mice in each group.The tumor volume of each group was observed,the tumor weight was recorded,and the expression of PD-1 and PD-L1 proteins in the tumor tissue of each group were detected by Western blot.Results Compared to the NK group,the CAR-NK group showed significantly decreased proliferation rate,and numbers of migration and invasion of SGC7901 and MGC803 cells(P<0.05).Compared to the NK group,the number of S phase cells increased,while G2/M phase cells decreased in the CAR-NK group(P<0.05).Compared to the NK group,the mRNA and protein expression levels of PD-1 and PD-L1 significantly downregulated in SGC7901 cell of the CAR-NK group(P<0.05).In the xenograft mouse model,compared to the NK treatment group,the protein expression of PD-1 and PD-L1 downregulated in the tumor tissues of the CAR-NK treatment group,with smaller tumor volume and decreased tumor weight,the differences were statistically significant(P<0.05).Compared to the blank control group,the CAR-NK treatment group exhibited downregulated protein expression of PD-1 and PD-L1 in tumor tissues,reduced tumor volume,and decreased tumor weight,with statistically significant differences(P<0.05).Compared to the CAR-NK treatment group,the CAR-NK+rhPD-1 treatment group showed upregulated expression of PD-1 protein,large tumor volume,and increased tumor weight,with statistically significant differences(P<0.05).Compared to the CAR-NK treatment group,the CAR-NK+rhPD-L1 treatment group exhibited upregulated expression of PD-L1 protein,large tumor volume,and increased tumor weight,with statistically significant differences(P<0.05).Conclusion CAR-NK cell therapy have a significant inhibitory effect on the proliferation,migration,and invasion of gastric cancer cells,resulting in the gastric cancer cell cycle arrest,which may inhibit the growth of xenograft tumors by inhibiting the PD-1/PD-L1 axis.

To achieve efficient and rapid detection of duck astrovirus type 2(DAstV-2),RPA prim-ers and crRNA were designed and synthesized based on the conserved sequence of the ORF2 gene of DAstV-2.A detection method for DAstV-2 was constructed,integrating RPA nucleic acid ampli-fication,LwCas13a cleavage,and colloidal gold lateral flow dipstick visualization.The specificity,sensitivity,and concordance of this detection method were evaluated.The experimental results showed that the detection limit for the DAstV-2 recombinant plasmid standard was 1.2×101 cop-ies/μL,which is superior to the conventional RT-PCR method.The method can specifically detect DAstV-2 pathogenic nucleic acids without cross-reactivity with DAstV-1,DAstV-3,DAstV-4,duck plague virus(DEV),and duck tembusu virus(DTMUV).When testing liver tissue samples from ducks suspected of being infected with DAstV-2,the results obtained using this method were com-pletely consistent with those from real-time quantitative PCR,with a 100％concordance rate.How-ever,this method is simpler and faster to perform.The research indicates that the established RPA-CRISPR/Cas13a-LFD detection system has high sensitivity,strong specificity,and high accuracy,capable of completing rapid visual detection of DAstV-2 nucleic acids within 1 h at a constant tem-perature of 37 ℃,providing a new technical platform for the rapid diagnosis of DAstV-2.

Objective To systematically evaluate malnutrition risk factors in diabetic foot patients through systematic review and inform evidence-based nutritional interventions.Methods A top-down search of the literature on risk factors for malnutrition in patients with diabetic foot was conducted according to the"6S"pyramid model,using a computerized decision-making system,clinical guideline websites,professional association websites and databases,with a timeframe of up to March 2025 for the search.Totally 2 researchers independently performed literature screening,quality assessment,and data extraction.Meta-analysis was conducted using Stata 18 software.Results Totally 23 studies with a total sample size of 5 068 cases were included.There were 10 influencing factors being extracted,including age(OR=2.709),BMI(MD=0.709),duration of diabetes mellitus(OR=2.589),glyco-sylated hemoglobin(OR=2.190),albumin(MD=0.578),hemoglobin(OR=2.948),infection(OR=1.816),C-reactive protein(OR=2.228),Wagner classification of diabetic foot(OR=4.620)and degree of self-care(OR=0.220).The incidence of malnutrition in DFU patients who were assessed by the MNA-SF tool,the MNA tool and GLIM tool were 52.2％,70.2％and 41.4％.Conclusion The incidence of malnutrition in DFU patients is relatively high.Healthcare providers should continuously monitor the nutritional status of diabetic foot patients and implement personalized intervention plans to prevent malnutrition.

Objective To develop a novel protective ventilator circuit component and to verify its performance by water seal and anti-splash experiments.Methods A novel protective ventilator circuit component had a design scheme with the multifunctional joint,and consisted of a tee connection tube,an isolation sleeve and a stop sleeve,of which,the tee connection tube was made of polyethylene polymer material and the others were made of silicone material.The tee connection tube had a T-shaped structure with two standard connection ports,which was composed of an adapter,a sealing cap,a plug and a sealing ring;the isolation sleeve was in the shape of a cylinder with a raised bottom,which was inserted into the adapter;the stop sleeve was located in the isolation sleeve,with an inverted frustum of a cone at the bottom and a rounded hole in the middle of the inverted frustum.An open ventilator circuit tube was involved in the performance verification of the circuit component developed.In the water seal experiment,sputum aspiration was simulated and the heights of the liquid level drop in the L-shaped tubes were compared after sputum aspiration.In the anti-splash experiment,the infection rates on the surfaces of the sterile hole towels and gloves were calculated.Results Water seal experiment showed after sputum aspiration the open ventilator circuit tube had the liquid level at the L-shaped tube higher significantly than that of the circuit component;the anti-splash experiment indicated sputum aspiration resulted in the occurance of the splashing out of the secretion and 77.5%infection rate by the open ventilator circuit tube,while no splashing out and 0%infection rate by the circuit component developed.Conclusion The novel protective ventilator circuit component behaves well in sealing and anti-splashing,and thus is worthy of clinical application for sputum aspiration.[Chinese Medical Equipment Journal,2025,46(4):113-117]

Objective To design an intelligent airborne soldier physical training system based on human body composition analysis to solve the problems in diversity of training mode,targeted training plan and high incidence of military training-related injuries.Methods The intelligent airborne military physical training system was designed with B/S architecture and developed with Python language,which was composed of four functional modules for airborne soldier information acquisition,trainee physical fitness state assessment,physical fitness training program recommendation and airborne soldier physical fitness training program evaluation.The airborne soldier information acquisition module collected and analyzed the trainee physiological parameter information with a human body composition analyzer,clarified the parameter characteristics related to physical training with considerations on military physical training requirements and constructed a trainee physical fitness assessment parameter model;the trainee physical fitness state assessment module established an evaluation model based on machine learning to realize stage-by-stage physical fitness evaluation for airborne soldiers;the physical fitness training program recommendation module was constructed based on the physical training feature similarity algorithm and graph embedding theory to provide decision making assistance for program development of airborne military physical training;the airborne soldier physical fitness training program evaluation module compared the physical fitness and evaluation results before and after training by means of list and chart,and updated the training program based on the evaluation results by calling the physical training program recommendation module.Results The intelligent airborne soldier physical training system contributed to forming an individualized physical fitness training recommendation mechanism after trainee body evaluation,modifying training program based on comparison and feedback for stage-by-stage training evaluation,so as to decrease the incidence of military training-related injuries while increasing the training efficiency.Conclusion The system developed improves airborne soldier physical training in rationality and reliability,and provides references for intelligent military training of the PLA.[Chinese Medical Equipment Journal,2025,46(2):16-23]

BACKGROUND:Alpinetin has anti-inflammatory,antitumor and antibacterial effects and has been proven to alleviate osteoporosis,but the effect and mechanism of alpinetin on osteoporotic fractures are still unclear.OBJECTIVE:To investigate the improvement effect of alpinetin in rates with osteoporotic fracture by regulating the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA)/cAMP-responsive element binding protein (CREB) signaling pathway.METHODS:A rat model of osteoporotic fracture was constructed using bilateral ovariectomy. The successfully modeled rats were randomly separated into model group,low-,medium-,and high-dose alpinetin group,and inhibitor group,with 12 rats per group. Another 12 rats were regarded as the sham operation group. On the day of fracture,rats in the low-,medium-,and high-dose alpinetin groups were gavaged with 7.5,15,and 30 mg/kg alpinetin+intraperitoneally injected with an equal amount of normal saline,respectively;the inhibitor group was gavaged with 30 mg/kg alpinetin+intraperitoneally injected with 5 mg/kg H-89 (a pathway inhibitor);and the model and sham operation groups were given (gavaged+intraperitoneally injected) an equal amount of normal saline,once a day for 8 consecutive weeks. Radiological examination was applied to evaluate fracture healing and assess healing scores;bone mineral density scanners were used to measure bone mineral density at the fracture site;three-point bending experiment and compression experiment were conducted to evaluate the biomechanical status of the femur;pathological damage at the fracture site in rats was observed by hematoxylin-eosin staining;enzyme linked immunosorbent assay (ELISA) was used to detect changes in serum alkaline phosphatase,osteocalcin,type Ⅰ collagen cross-linked C-terminal peptide,and cAMP levels;western blot was applied to detect the expression of bone morphogenetic protein 2 and cAMP/PKA/CREB pathway proteins in femoral tissue.RESULTS AND CONCLUSION:Compared with the sham operation group,the fracture healing score,bone mineral density,maximum load,maximum stress,alkaline phosphatase,osteocalcin,cAMP levels,bone morphogenetic protein 2,p-PKA/PKA,p-CREB/CREB expression in the model group were decreased,the level of type Ⅰ collagen cross-linked C-terminal peptide was increased (P<0.05). The above indicators showed opposite changes in all the alpinetin groups compared with the model group (P<0.05). Compared with the high-dose alpinetin group,the changes in the above indicators were reversed in the inhibitor group (P<0.05). To conclude,alpinetin may accelerate fracture healing in osteoporotic fracture rats,by activating the cAMP/PKA/CREB signaling pathway.

Objective To investigate the effect and potential mechanism of chimeric antigen receptor(CAR)-natural killer(NK)cell therapy on the growth of gastric cancer cells and xenograft tumors.Methods Cell experiments:The gastric cancer cell lines of SGC7901 and MGC803 were co-cultured with CAR-NK cells as the CAR-NK group,the NK cells were co-cultured with SGC7901 and MGC803 cells as the NK group,respectively.The mRNA levels of PD-1 and PD-L1 in both groups were detected by RT-qPCR.The cell proliferation ability was assessed using EdU staining and CCK-8 assay.The cell migration and invasion abilities were detected by Transwell assay.The change of cell cycle was detected by flow cytometry.The expression of PD-1 and PD-L1 proteins in cells was detected by Western blot.Animal experiments:Mice were established model of xenograft tumors and divided into the blank control group(inoculated with routinely cultured SGC7901 cells),NK treatment group(inoculated SGC7901 cells combined NK cells),CAR-NK treatment group(inoculated SGC7901 cells combined CAR-NK cells),CAR-NK+rhPD-1 treatment group(inoculated SGC7901 cells combined CAR-NK cells,with intraperitoneal injection of 5 mg/kg rhPD-1 concurrently),and CAR-NK+rhPD-L1 treatment group(inoculated SGC7901 cells combined CAR-NK cells,with intraperitoneal injection of 5 mg/kg rhPD-L1 concurrently),with 5 mice in each group.The tumor volume of each group was observed,the tumor weight was recorded,and the expression of PD-1 and PD-L1 proteins in the tumor tissue of each group were detected by Western blot.Results Compared to the NK group,the CAR-NK group showed significantly decreased proliferation rate,and numbers of migration and invasion of SGC7901 and MGC803 cells(P<0.05).Compared to the NK group,the number of S phase cells increased,while G2/M phase cells decreased in the CAR-NK group(P<0.05).Compared to the NK group,the mRNA and protein expression levels of PD-1 and PD-L1 significantly downregulated in SGC7901 cell of the CAR-NK group(P<0.05).In the xenograft mouse model,compared to the NK treatment group,the protein expression of PD-1 and PD-L1 downregulated in the tumor tissues of the CAR-NK treatment group,with smaller tumor volume and decreased tumor weight,the differences were statistically significant(P<0.05).Compared to the blank control group,the CAR-NK treatment group exhibited downregulated protein expression of PD-1 and PD-L1 in tumor tissues,reduced tumor volume,and decreased tumor weight,with statistically significant differences(P<0.05).Compared to the CAR-NK treatment group,the CAR-NK+rhPD-1 treatment group showed upregulated expression of PD-1 protein,large tumor volume,and increased tumor weight,with statistically significant differences(P<0.05).Compared to the CAR-NK treatment group,the CAR-NK+rhPD-L1 treatment group exhibited upregulated expression of PD-L1 protein,large tumor volume,and increased tumor weight,with statistically significant differences(P<0.05).Conclusion CAR-NK cell therapy have a significant inhibitory effect on the proliferation,migration,and invasion of gastric cancer cells,resulting in the gastric cancer cell cycle arrest,which may inhibit the growth of xenograft tumors by inhibiting the PD-1/PD-L1 axis.

To achieve efficient and rapid detection of duck astrovirus type 2(DAstV-2),RPA prim-ers and crRNA were designed and synthesized based on the conserved sequence of the ORF2 gene of DAstV-2.A detection method for DAstV-2 was constructed,integrating RPA nucleic acid ampli-fication,LwCas13a cleavage,and colloidal gold lateral flow dipstick visualization.The specificity,sensitivity,and concordance of this detection method were evaluated.The experimental results showed that the detection limit for the DAstV-2 recombinant plasmid standard was 1.2×101 cop-ies/μL,which is superior to the conventional RT-PCR method.The method can specifically detect DAstV-2 pathogenic nucleic acids without cross-reactivity with DAstV-1,DAstV-3,DAstV-4,duck plague virus(DEV),and duck tembusu virus(DTMUV).When testing liver tissue samples from ducks suspected of being infected with DAstV-2,the results obtained using this method were com-pletely consistent with those from real-time quantitative PCR,with a 100％concordance rate.How-ever,this method is simpler and faster to perform.The research indicates that the established RPA-CRISPR/Cas13a-LFD detection system has high sensitivity,strong specificity,and high accuracy,capable of completing rapid visual detection of DAstV-2 nucleic acids within 1 h at a constant tem-perature of 37 ℃,providing a new technical platform for the rapid diagnosis of DAstV-2.

Objective To develop a novel protective ventilator circuit component and to verify its performance by water seal and anti-splash experiments.Methods A novel protective ventilator circuit component had a design scheme with the multifunctional joint,and consisted of a tee connection tube,an isolation sleeve and a stop sleeve,of which,the tee connection tube was made of polyethylene polymer material and the others were made of silicone material.The tee connection tube had a T-shaped structure with two standard connection ports,which was composed of an adapter,a sealing cap,a plug and a sealing ring;the isolation sleeve was in the shape of a cylinder with a raised bottom,which was inserted into the adapter;the stop sleeve was located in the isolation sleeve,with an inverted frustum of a cone at the bottom and a rounded hole in the middle of the inverted frustum.An open ventilator circuit tube was involved in the performance verification of the circuit component developed.In the water seal experiment,sputum aspiration was simulated and the heights of the liquid level drop in the L-shaped tubes were compared after sputum aspiration.In the anti-splash experiment,the infection rates on the surfaces of the sterile hole towels and gloves were calculated.Results Water seal experiment showed after sputum aspiration the open ventilator circuit tube had the liquid level at the L-shaped tube higher significantly than that of the circuit component;the anti-splash experiment indicated sputum aspiration resulted in the occurance of the splashing out of the secretion and 77.5%infection rate by the open ventilator circuit tube,while no splashing out and 0%infection rate by the circuit component developed.Conclusion The novel protective ventilator circuit component behaves well in sealing and anti-splashing,and thus is worthy of clinical application for sputum aspiration.[Chinese Medical Equipment Journal,2025,46(4):113-117]

Objective:To explore the effect and mechanism of CD147 on differentiation of circulating fibrocytes and its pro-inflammatory and pro-fibrotic function.Methods:Circulating fibrocytes were extracted from peripheral blood of asthma patients,stimu-lated with CD147,and intervened with CD147 antagonist AP-9 or p38/MAPK inhibitor SB203580.Cell viability was detected by CCK-8 method,cell migration was assessed by Transwell method,expressions of collagen type Ⅰ(COL-Ⅰ),CD45 and α-SMA were detected by immunofluorescence staining.Levels of cytokines such as TGF-β1,IL-4,IL-5 and IL-13 were detected by ELISA,and expression levels of COL-Ⅰ,fibronectin(FN),α-SMA,p-TAK1,p-P38 and other proteins were detected by Western blot.Results:Low dose of CD147 increased cell viability of circulating fibrocytes.CD147 significantly promoted migration of circulating fibrocytes and induces their differentiation into myofibrocytes.CD147 significantly increased secretion of cytokines such as TGF-β1,IL-4,IL-5 and IL-13 in circulating fibrocytes.CD147 significantly increased expressions of COL-Ⅰ,FN,α-SMA,p-TAK1,p-P38 in circulating fibrocytes.AP-9 or SB203580 significantly inhibited effect of CD147 on circulating fibrocytes.Conclusion:CD147 can promote proliferation,mi-gration,differentiation and pro-inflammatory and profibrotic function of circulating fibrocytes in vitro,and TAK1-p38/MAPK signaling pathway is involved in CD147-mediated regulation of circulating fibrocytes.