Objective: To compare the biological characteristics of human induced pluripotent stem cell-derived platelet exosomes (hiPSC-Plt-Exos) with those of conventional apheresis platelet exosomes (Plt-Exos), specifically focusing on their differential abilities to enhance the proliferation and migration of human umbilical cord mesenchymal stem cells (hUC-MSCs). Methods: Exosomes were isolated from hiPSC-derived Plt and apheresis Plt concentrate using size exclusion chromatography. These exosomes were then characterized through nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and Western blotting. Co-culture experiments into hUC-MSCs were conducted with hiPSC-Plt-Exos and apheresis Plt-Exos, respectively. Their effects on the proliferation and migration of hUC-MSCs were assessed via cell proliferation assays and scratch tests. Results: hiPSC-Plt-Exos and apheresis Plt-Exos exhibited comparable particle sizes, morphological features (such as the characteristic cup-shaped structure), and surface markers (including CD9 and HSP70). Notably, hiPSC-Plt-Exos demonstrated a significantly greater ability to enhance the proliferation and migration of hUC-MSCs compared to apheresis Plt-Exos (P<0.05). These differences provide critical comparative data for their application in various clinical contexts. Conclusion: This study establishes a theoretical foundation for developing precise therapeutic strategies based on hiPSC-Plt-Exos. Furthermore, it underscores the necessity of selecting the appropriate type of exosomes according to the specific disease microenvironment to achieve optimal therapeutic outcomes.

Objective To explore characteristics of clinical and imaging findings in patients with fat embolism syndrome.Methods From January 2021 to October 2022,clinical manifestations of 13 patients with fat embolism due to fracture or or-thopaedic surgery were retrospectively analyzed,including 11 males and 2 females,aged from 17 to 60 years old.Mental and respiratory abnormalities and changes in vital signs occurred after admission or after surgery,and patient's chest and brain imaging results were abnormal.The patient's mental and respiratory abnormalities,vital signs,chest and brain imaging results were continuously monitored.Results The main clinical manifestations of fat embolism syndrome were abnormal pulmonary respiration in 13 patients,abnormal central nervous function in 7 patients,and spotted rash in 2 patients.Chest CT showed dif-fuse distribution of ground glass shadows in 13 patients,and severe symptoms were"snowstorm".Nine patients with ground glass fusion consolidation,5 patients with multiple nodules and 4 patients accompanied by bilateral pleural effusion.Head CT findings of 5 patients were negative,and head MRI findings of 1 patient showed multiple T1WI low signal,T2WI high signal shadow,DWI high signal shadow,and"starry sky sign"in basal ganglia,radiative crown,hemioval center,thalamus,frontal parietal cortex and subcortex.Conclusion Fat embolism syndrome has a high mortality rate.Clinical manifestations of respira-tory system and nervous system are not specific,and the skin spot rash has a characteristic manifestation.The"blizzard"sign is the specific manifestation of chest X-ray and CT examination of fat embolism,and the"starry sky"sign is the typical manifesta-tion of diffusion-weighted sequence of brain MRI examination of fat embolism.

Heterotypic cell-in-cell structures(heCICs)mediate unique non-autonomous cell death,which are widely involved in a variety of important pathological processes,such as tumorigenesis,pro-gression and clinical prognosis.Methylenetetrahydrofolata dehydrogenase 2(MTHFD2),one of the key enzymes of one-carbon metabolism,is highly expressed in a variety of tumor cells.In this study,in order to investigate the effect of MTHFD2 on the formation of heCICs,liver cancer cells and immune cells were first labeled separately by live cell dyes,and the heCIC model was established by using fluorescence mi-croscopy for cell imaging and analysis.After transiently knocking down MTHFD2 in cells by RNAi,we found that the ability of PLC/PRF/5 and Hep3B to form heCICs with immune cells was significantly in-creased(all P＜0.01).MTHFD2 recombinant expression plasmid was constructed by the homologous re-combination method,and MTHFD2 overexpression cell lines were further constructed.Then,the effect of MTHFD2 overexpression on the ability to form heCICs was detected by co-culturing the overexpression cell lines with immune cells.The results showed that the rate of heCIC formation was significantly re-duced after overexpression of MTHFD2(all P＜0.001).In conclusion,this study demonstrated that MTHFD2 is a negative regulator of heCIC formation,providing a research basis for targeting MTHFD2 to promote heCIC formation and enhance the in-cell killing of immune cells.

Objective:To explore the therapeutic efficacy and prognostic factors of induction therapy for secondary central nervous system lymphoma(SCNSL).Methods:Clinical data of patients diagnosed with SCNSL from 2010 to 2021 at Guangdong Provincial People's Hospital were retrospectively collected.A retrospective cohort study was performed on all and grouped patients to analyze the efficacy and survival.Multivariate logistic regression analysis was used to explore the adverse prognostic factors.Results:Thirty-seven diffuse large B-cell lymphoma patients with secondary central involvement were included in the research.Their 2-year overall survival(OS)rate was 46.01％and median survival time was 18.1 months.The 2-year OS rates of HD-MTX group and TMZ group were 34.3％and 61％,median survival time were 8.7 and 38.3 months,and median progression-free survival time were 8.1 and 47 months,respectively.Multivariate logistic regression analysis showed that age,sex,IPI,Ann Arbor stage were correlated with patient survival time.The median survival time of patients with CD79B,KMT2D,CXCR4.ERBB2,TBL1XR1,BTG2,MYC,MYD88,and PIM1 mutations was 8.2 months,which was lower than the overall level.Conclusion:HD-MTX combined with TMZ as the first-line strategy may improve patient prognosis,and early application of gene sequencing is beneficial for evaluating prognosis.

Objective:To investigate the effect of genetic polymorphism of MTHFR C677T (rs1801133) on methotrexate (MTX) related toxicity in pediatric mature B-cell lymphoma patients. Methods:Fifty-eight intermediate and high risk patients under 18 years of age with mature B-cell lymphoma who received 5 g/m2 MTX (24 h intravenous infusion) in Sun Yat-sen University Cancer Center from August 2014 to December 2021 were included,and their toxicity of high-dose MTX (HD-MTX) were monitored and analyzed. Results:Among the 58 pediatric patients,the number of CC,CT,and TT genotypes for MTHFR C677T was 33,19 and 6,respectively. A total of 101 courses of HD-MTX therapy were counted,of which plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion were observed in 35 courses,≤0.2 μmol/L in 66 courses. Inter-group comparison showed that plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion increased the risk of developing oral mucositis (P<0.05). Compared with wild-type (CC genotype),patients in the mutant group (CT+TT genotype) were more likely to develop myelosuppression,manifested as anemia,leucopenia,neutropenia and thrombocytopenia. However,plasma MTX level at 48 h was not associated with MTHFR C677T gene polymorphism. Conclusion:The risk of developing oral mucositis in children with mature B-cell lymphoma is associated with plasma MTX concentration. Polymorphism of MTHFR C677T gene is not related to plasma MTX concentration in children with mature B-cell lymphoma,but is related to grade Ⅲ to Ⅳ hematological toxicity.

Objective:To explore the differential impact of the alignment between service capability and job satisfaction on job performance among primary general practitioner,and to provide a reference for enhancing their job performance.Methods:A survey was conducted with 620 primary general practitioner using questionnaires.The relationships among service capability,job satisfaction,and job performance were analyzed using polynomial regression and response surface analysis methods.Results:Under the condition of"service capability—job satisfaction alignment,"compared to the scenario of"low service capability—low job satisfaction,"primary general practitioner with"high service capability—high job satisfaction"demonstrated significantly higher job performance(a1=0.875,P＜0.001;a2=-0.068,P＞0.05).In the misalignment condition,compared to"low service capability—high job satisfaction,"those with"high service capability—low job satisfaction"also showed higher job performance(a3=0.265,P＜0.001;a4=-0.064,P＞0.05).Conclusion:Both service capability and job satisfaction significantly influence job performance among primary general practitioner,with service capability being a key factor for achieving high work performance.It is essential to enhance the service capability of primary general practitioner and adopt multiple strategies to improve job satisfaction,thereby effectively boosting work performance.

Objective To compare the oral cleansing effects of the microbubble toothbrush and the conventional pulsed oral irrigator to provide references for users.Methods Ninety identical 3D-printed resin tooth models were grouped and subjected to repeated experiments,which were divided randomly into five groups including a microbubble toothbrush high-speed gear(GN-H)group,a microbubble toothbrush medium-speed gear(GN-M)group,a microbubble low-speed gear(GN-L)group,a conventional pulsed oral irrigator high-speed gear(W-H)group and a conventional pulsed oral irrigator low-speed gear(W-L)group,with 18 teeth in each group.The cleansing effects of the microbubble toothbrush and the conventional pulsed oral irrigator were evaluated in terms of irrigating strength and abilities for eliminating plaque and debris.Results Both the two types of water flossers were provided with high irrigating strength and effectively reduced plaque and debris on tooth surfaces,and the GN-H,GN-M and GN-L groups behaved better significantly than the remained groups.The order of the five groups was GN-H group＞GN-M group＞W-H group＞GN-L group＞W-L group for irrigating strength,GN-H group＞GN-M group＞GN-L group＞W-H group＞W-L group for plaque removal,GN-H group＞GN-M group＞W-H group＞GN-L group＞W-L group for debris removal,with all the differences being statistically significant(P＜0.05).Conclusion Both the two types of water flossers remove plaque and debris effectively,while the microbubble toothbrush gains advantages over the conventional pulsed oral irrigator.[Chinese Medical Equipment Journal,2024,45(9):67-72]

Background:Gastric cancer is a malignant tumor originating from the gastric mucosal epithelium.OLGA/OLGIM staging systems are scoring systems for gastric mucosal atrophy and intestinal metaplasia based on gastroscopic pathology.Serum pepsinogen(PG)and PG Ⅰ/PG Ⅱ ratio(PGR)can reflect the gastric mucosal function and status.Studying the relationship between PG and OLGA/OLGIM stages and the changing trends is of great value for early screening of gastric cancer.Aims:To explore the relationship between serum PG and OLGA/OLGIM stages,and its application value in screening of early gastric cancer.Methods:A total of 188 healthy individuals underwent gastroscopy from June 2021 to June 2023 at Shanghai Health and Medical Center were selected.The serum PG level was measured,and the status of Helicobacter pylori(Hp)infection was evaluated.OLGA/OLGIM stages were assessed according to the findings of gastroscopic pathology,and correlated with the serum PG level.After two years of follow-up,changes of PG and PGR in subjects with different baseline OLGA/OLGIM stages were analyzed.Results:There were significant differences in PG Ⅰand PGR among subjects with various baseline OLGA/OLGIM stages(P＜0.05).OLGA/OLGIM stages were correlated with Hp infection,family history of malignant gastrointestinal tumors and spicy diet(P＜0.05).The incidences of gastric mucosal atrophy in PG Ⅰ ≤70 μg/L group and PGR≤3.0 group were significantly higher than those in PG Ⅰ＞70 μg/L group and PGR＞3.0 group,respectively(P＜0.05).The follow-up results showed that for baseline OLGA/OLGIM stage 0,PG Ⅰ showed a decreasing trend over time,while no significant change of PG Ⅰ was found in other OLGA/OLGIM stages;PG Ⅱ showed a decreasing trend while PGR showed an increasing trend over time in all stages.But all these trends were not statistically significant(P＞0.05).Conclusions:The combined detection of PG and Hp infection has important value in evaluating the severity of chronic atrophic gastritis and the risk of gastric cancer.It can be applied as an early screening project for gastric cancer in individuals undergoing physical examination.

Objective To investigate the nutritional status of children with Crohn's Disease (CD) at diagnosis and its association with clinical characteristics. Methods A retrospective analysis was performed for the clinical data and nutritional status of 118 children with CD who were admitted to Beijing Children's Hospital,Capital Medical University,from January 2016 to January 2024. A multivariate logistic regression analysis was used to investigate the risk factors for malnutrition. Results A total of 118 children with CD were included,among whom there were 68 boys (57.6％) and 50 girls (42.4％),with a mean age of (11±4) years. Clinical symptoms mainly included recurrent abdominal pain (73.7％,87/118),diarrhea (37.3％,44/118),and hematochezia (32.2％,38/118),and 63.6％ (75/118) of the children had weight loss at diagnosis. The incidence rate of malnutrition was 63.6％ (75/118),and the children with moderate or severe malnutrition accounted for 67％ (50/75). There were 50 children (42.4％) with emaciation,8 (6.8％) with growth retardation,and 9 (7.6％) with overweight or obesity. Measurement of nutritional indices showed a reduction in serum albumin in 83 children (70.3％),anemia in 74 children (62.7％),and a reduction in 25 hydroxyvitamin D in 15 children (60％,15/25). The children with malnutrition had significantly higher disease activity,proportion of children with intestinal stenosis,and erythrocyte sedimentation rate and a significant reduction in serum albumin (P<0.05). The multivariate logistic regression analysis showed that intestinal stenosis was an independent risk factor for malnutrition in children with CD (OR=4.416,P<0.05). Conclusions There is a high incidence rate of malnutrition in children with CD at diagnosis,which is associated with disease activity and disease behavior. The nutritional status of children with CD should be closely monitored.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.