Objective To construct myeloid-specific Spi1 gene knockout mice and analyze their genotypes,so as to provide animal model basis for the study of pathological mechanism of diseases and drug targets.Methods Ac-cording to the principle of CRISPR/Cas9 technology and Cre/LoxP system,sgRNA and Donor vectors were de-signed and constructed.The transcript of Exon 2(Exon 2)was used as the knockout region,and Loxp elements were placed on both sides of Exon 2.Cas9 protein,sgRNA and Donor vector were mixed and microinjected into the fertilized eggs of C57BL/6J mice,the fertilized eggs were transplanted into the uterus of C57BL/6J pregnant female mice,and F0 generation was obtained after 19～20 days.Positive F0 mice were mated with C57BL/6J mice to ob-tain stable F1 Spi1flox/+mice.Spi1flox/+mice of F1 generation were selfed to obtain Spi1flox/flox mice.Spi1flox/flox mated with Lyz2-Cre+mice to obtain Spi1flox/+/Lyz2-Cre+mice,and then mated with Spi1flox/flox,the Spi1flox/flox/Lyz2-Cre+mice were myeloid-specific Spi1 gene knockout(KO)mice.Spi1flox/flox/Lyz2-cre-mice were used as wild-type(WT)mice.DNA of WT and KO mice was extracted,and the genotypes were identified by agarose gel electro-phoresis after PCR amplification.Western blot was used to detect the expression of spleen focus forming virus provi-ral integration oncogene,Spi-1/purine rich box-1(PU.1)in immune cells of WT and KO mice.Results The results of PCR identification showed that the genotype of mice with only 220 bp amplified by flox primer was Spi1flox/flox homozygote,and the genotype of mice with 700 bp amplified by Lyz2-Cre primer was Lyz2-Cre+.Western blot showed that compared with WT group,the protein PU.1 was not expressed in bone marrow-derived macropha-ges(BMDMs)and peritoneal macrophages(PM)in KO group(P<0.01).There was no significant difference of statistics in the expression level of PU.1 in T cells between KO mice and WT mice.The results of PCR and West-ern blot showed that myeloid-specific Spi1 KO mice were successfully constructed.Conclusion The myeloid-spe-cific Spi1 gene KO mice are successfully constructed and identified,which provides animal model basis for further revealing the potential mechanism of PU.1 inimmune regulation.

Objective To breed and identify the T lymphocyte-conditional Spi1 knockout mice for the further in-vestgation of the specific role of Spi1-encoded protein PU.1.Methods The Lck-Cre mice were mated with Spi1flox/flox mice to obtain Lck-Cre×Spi1flox/flox mice(T lymphocyte-specific Spi1 knockout mice),and the genotype was determined by polymerase chain reaction(PCR)and agarose gel electrophoresis.Magnetic beads were used to sort out the splenic T lymphocytes,and the knockdown efficiency of PU.1 in T cells was detected by Western blot,quantitative real-time PCR(qPCR)and flow cytometry.Results The Lck-Cre×Spi1flox/flox mouse genotype was stably inherited.Compared with Spi1flox/flox mice,the expression level of PU.1 was significantly reduced in splenic T cells of Lck-Cre×Spi1flox/flox mice.Conclusion In this study,the T lymphocyte-specific Spi1 knockout mice was successfully constructed by applying Cre/LoxP system and CRISPR/Cas9 technology,which provided a reliable an-imal model for the subsequent experiments of the specific role of PU.1 in T cell-related diseases.

Objective To construct Csf1r-CreERT2 R26REYFP reporter gene mice and assess the efficacy of Csf1r-CreERT2-mediated enhancement of CSF1R in CD45+cells labeled with yellow fluorescein protein EYFP.Methods Csf1r-CreERT2 mice were crossbred with R26REYFP homozygous mice,and Csf1r-CreERT2R26REYFP mice were identified through PCR and Western Blot analyses.Flow cytometry was employed to evaluate CSF1R tag-efficiency in CD45+cells across different mouse tissues following tamoxifen induction.Results Csf1r-CreERT2 R26REYFP reporter gene mice were acquired.In addition,it was found that Csf1r-CreERT2-mediated EYFP could effectively mark CSF1R in various tissues of mice and CD45+cells in different locations.Compared to the R26REYF P group,the highest labeling efficiency was observed in the brain tissue(P＜0.001),the lowest in the thymus tissue(P＜0.05),and no sig-nificant difference was observed in the spleen tissue.Conclusion Adult Csf1r-CreERT2 mice and R26REYFP mice are effective ways to obtain Csf1r-CreERT2 R26REYFP induced conditional fluorescence mice.Csf1r-CreERT2 can mediate EYFP to effectively trace CSF1R in CD45+cells in different parts of mice.

Aim To investigate the inhibition role and mechanism of adipose derived mesenchymal stem cell(ADMSC)exosomes(Exo)on adverse ventricular remodeling after myocardial infarction(MI).Methods The chan-ges of autophagy and inflammasomes phenotype of cardiac fibroblasts after H2O2 treatment were observed.MI rats were in-jected with an equal volume of normal saline,adipose derived mesenchymal stem cell exosomes(MSC-Exo)or fibroblast exosomes(MEF-Exo)via a tail vein.The expression of autophagy related 16 like protein 1(ATG16L1),autophagy re-lated protein 7(ATG7)and NOD-like receptor protein 3(NLRP3),inflammatory response,the degree of myocardial fi-brosis,and the cardiac function were observed in different groups.Results After treatment with H2O2 on cardiac fi-broblasts,the expressions of ATG16L1 and ATG7 were significantly decreased(P＜0.001),NLRP3 was significantly in-creased(P＜0.001),and the levels of inflammatory cytokines interleukin-1β(IL-1β)and IL-18 were significantly elevated(P＜0.001).After MI rats were intervened with MSC-Exo,the expressions of autophagy related proteins ATG16L1 and ATG7 were significantly up-regulated(P＜0.001),NLRP3 was significantly down-regulated(P＜0.001),serum IL-1β and IL-18 levels were significantly decreased(P＜0.001),fibrosis-related proteins collagen Ⅰ and Ⅲ were significantly reduced(P＜0.001),myocardial fibrosis was significantly relieved(P＜0.001),and cardiac function was sig-nificantly improved(P＜0.001).Conclusion Adipose derived MSC-Exo play a role in inhibiting adverse ventricular remodeling after MI by regulating the balance of autophagy and NLRP3 inflammasomes.

Objective: To obtain chimeric antigen receptor macrophages ( CAR-M) targeting HER2 stably transfected． Methods : CAR lentivirus vector targeting HER2 was constructed and infected with human monocytic leukemia cell line (THP-1) ．CAR THP-1 cells with green fluorescent labeling were selected by sorting flow cytometry and continued to be cultured in vitro．The CAR THP-1 cells targeting HER2 were co-cultured with the endometrial cancer cell line Ishikawa with negative and positive HER2 expression，and their targeted phagocytosis of CAR-M to HER2 positive tumor cells was detected by imaging flow cytometry ，and the targeted phagocytosis efficiency of CAR-M to HER2 positive tumor cells was detected by flow cytometry. Results : CAR lentivirus infection with THP- 1 cells was less efficient ; After co-culture with cancer cells，flow cytometry and imaging flow cytometry showed that CAR THP-1 cells had enhanced phagocytosis of HER2 positive Ishikawa cells compared with the empty body group (P＜0. 01) ． Conclusion In this experiment，CAR THP-1 cell line targeting HER2 was established by constructing CAR lentivirus vector and transfecting THP-1 cells ，and it was proved that CAR THP-1 could phagocytize HER2 positive Ishikawa cells through specific targeting.

Objective To investigate the effect of Ⅲ-type phosphatidylinositide 3 kinase (PI3K) pathway adjusting autophagy on brain damage mechanism after cardiopulmonary resuscitation (CPR) and hypothermia treatment.Methods The asphyxia induce cardiac arrest-CPR model was reproduced on healthy male Sprague-Dawley (SD) rats.Sixty rats after restoration of spontaneous circulation (ROSC) were randomly divided into normothermia group,therapeutic hypothermia group and PI3K inhibitor 3-methyl adenine (3-MA) pretreatment group,differentiated by 24 hours and 48 hours after ROSC.Each group had 10 rats at each time point.The anal temperature in the normothermia group was maintained at (37.0 ± 0.2) ℃,and the rats in the hypothermia group were given cooling treatment immediately after ROSC,and the target rectal temperature was 32-34 ℃.In the 3-MA pretreatment group,10 mmol/L 3-MA 5 μL was injected into the ventricle 20 minutes before asphyxia,and other groups were given the same amount of normal saline.Ten rats without CPR were included in Sham group only received anesthesia and catheterization.The rats were sacrificed at 24 hours and 48 hours after ROSC respectively,and the brain tissues were harvested,the brain water content (BWC) was measured by dry-wet weight method.Western Blot was used to determine the autophagy related proteins Beclin-1 and microtubule-associated protein 1 light chain 3 (LC3),apoptosis related proteins Bcl-2 and caspase-3,and the Ⅲ-type PI3K pathway proteins Vps34 and Atgl4.Ultrastructural changes in brain tissue were observed with transmission electron microscope.Neurological deficit scores (NDS) was obtained in each group at 48 hours after ROSC.Results Compared with Sham group,the cortex at 24 hours after ROSC in normothermic group showed obvious edema,apeptosis and autophagy began to appear under transmission electron microscope,and the expressions of autophagy,apoptosis and Ⅲ-type PI3K-related proteins in brain tissue were significantly increased in a time-dependent manner,and the neurological function at 48 hours after ROSC was significantly damaged.After hypothermia intervention,brain edema of rats was significantly reduced,no obvious apoptosis was found,but autophagy was increased,the expressions of autophagy-related proteins Vps34,Atg14 and Ⅲ-type PI3K-related proteins Beclin-1 and LC3 at 48 hours after ROSC were further higher than those of normothermic group (Vps34/GAPDH:0.25±0.03 vs.0.15±0.04,Atg14/GAPDH:0.12±0.03 vs.0.05±0.04,Beclin-1/GAPDH:0.060±0.002 vs.0.018±0.002,LC3-Ⅱ/GAPDH:0.160±0.010 vs.0.050± 0.010,all P ＜ 0.05),the expressions of apoptosis related proteins Bcl-2 and caspase-3 were significantly lowered (Bcl-2/GAPDH:0.05±0.03 vs.0.20±0.04,caspase-3/GAPDH:0.050±0.002 vs.0.140±0.015,both P ＜ 0.05),neurological function was significantly improved (NDS:157±85 vs.343± 198,P ＜ 0.05).Pretreatment with 3-MA inhibited the protective effect of hypothermia on brain tissues.The expressions of Vps34,Atg14,Beclin-1 and LC3 in brain tissues at 48 hours after ROSC in 3-MA pretreatment group was significantly lower than those in the hypothennia group (Vps34/GAPDH:0.18±0.03 vs.0.25±0.03,Atg44/GAPDH:0.07±0.04 vs.0.12±0.03,Beclin-1/GAPDH:0.015±0.003 vs.0.060±0.002,LC3-Ⅱ/GAPDH:0.045±0.030 vs.0.160±0.010,all P ＜ 0.05),the expressions of Bcl-2 and caspase-3 were significantly increased (Bcl-2/GAPDH:0.15±0.04 vs.0.05±0.03,caspase-3/GAPDH:0.120±0.015 vs.0.050±0.002,both P ＜ 0.05),and NDS score was significantly increased (341±208 vs.157±85,P ＜ 0.05).Conclusion Hypothermia treatment reduced brain edema and ameliorated brain function after CPR,which might be related to increase autophagy and inhibit apoptosis adjustment by activating Ⅲ-type PI3K pathway.

Objective To study the clinical value of brain natriuretic peptide (BNP) and soluble urokinase plasminogen activator receptor (suPAR) in the diagnosis and prognosis of bloodstream infection.Methods Totally 165 patients suspected of bloodstream infection admitted in intensive care unit (ICU) of the Second Hospital Affiliated to Suzhou University were enrolled in this study.According to the diagnosis standard of bloodstream inflection,patients were divided into the bloodstream infection group and non-bloodstream infection group.According to the prognosis of the patients,the bloodstream infection group was further divided into the survival group and the death group.Serum levels of suPAR,BNP,CRP,PCT,and chronic health evaluation Ⅱ acute physiology score (APACHE Ⅱ),and mortality of the patients were analyzed,and the possible relation of the above indexes between the two groups were compared.Based on the receiver operating characteristic curve (ROC) and the area under the curve (AUC),the early diagnostic value of suPAR,BNP,CRP,PCT,and APACHE Ⅱ score in the bloodstream infection patients was determined.Results Serum levels of suPAR,BNP,CRP,PCT and APACHE Ⅱ score in the bloodstream infection group were higher than those in the non-bloodstream infection group (P＜0.05);Serum levels of suPAR,BNP,CRP,PCT and APACHE Ⅱ score in the death group were higher than those in the survival group (P＜0.05).There was a positive correlation between serum suPAR,BNP,PCT and APHCHE Ⅱ] score in patients of bloodstream infection(r=0.503,0.548,0.781,all P＜0.05).The levels of suPAR,BNP,PCT and APACHE Ⅱ in the patients of blood stream infection were related to significant the prognosis (P＜0.05).And these indexes can provide good evaluation on the prognosis of the patients.Conclusion Detection of serum suPAR,BNP can evaluate the severity of bloodstream infection and preliminarily determine the prognosis of patients with bloodstream infection.Therefore,the method is worth applying in the clinical field.

Mitral valve prolapse is a disease which causes mitral regurgitation,which is one of the common causes of mitral insufficiency.With the aggravation of blood reflux,mitral valve prolapse will eventually lead to pulmo-nary hypertension,heart failure and even death in children.The main diagnostic methods include chest X－ray,echocar-diography,spiral CT and magnetic resonance imaging.Mitral valvuloplasty is the main surgical method for mitral valve prolapse in children.It includes valvuloplasty,annuloplasty,tendon chordoplasty,edge－to－edge mitral valve repair, and so on.Now,the progress in surgical diagnosis and treatment of mitral valve prolapse in children were reviewed in or-der to provide a meaningful reference for its individual treatment.

An App for Android intelligent mobile phone to recite prescriptions in rhyme and learn infused pre-scriptions of traditional Chinese medicine was developed in order to meet the requirement of students majoring in traditional Chinese medicine and lovers of traditional Chinese medicine, which can show the assistant and guide of prescriptions in rhyme by different colors. An interface linked with each corresponding traditional Chinese medicine was added into the App to show its picture, properties, effect and application for the interaction between database server and mobile phone users and the aim to recite prescriptions of traditional Chinese medicine and learn tradi-tional Chinese medicine.

Objective To evaluate the diagnostic value of ultrasonography and MRI in the diagnosis of placenta accrete.Methods First,the relevant literatures about placenta accrete were retrieved at home and abroad,then the data were extracted and Meta-analysis was performed.The combined sensitivity and specificity of ultrasound and MRI and AUC were obtained.Results The combined sensitivity of ultrasonography was 0.80,specificity was 0.88,AUC was 0.88;combined sensitivity of MRI was 0.86,specificity was 0.90,AUC was 0.93.Conclusion Ultrasound and MRI are very valuable in the diagnosis of placenta accrete.However,MRI is a useful complement of ultrasound,and the diagnostic value is slightly better than that of ultrasound.The diagnostic value will be higher when they combined together.