Objective To construct an in vitro co-culture model of gastric cancer organoids and cancer-associated fibroblasts(CAFs),and investigate the role of cancer-associated fibroblasts in the proliferation and chemotherapy resistance of gastric cancer organoids.Methods Tumor tissues from 12 gastric cancer patients undergoing surgical treatment in Department of General Surgery of Second Affiliated Hospital of Army Medical University from February 2023 to March 2024 were collected to construct gastric cancer organoids using 3D culture.HE staining was used to observe the morphology,and immunohistochemical assay was employed to determine the expression of cytokeratin CK7,carcinoembryonic antigen(CEA),and proliferation marker Ki-67.After CAFs derived from the same patient were cultured,observed for their morphology under a light microscope,and detected for the phenotype by flow cytometry,the cells were co-cultured with gastric cancer organoids in a 1:1 ratio.Phase-contrast microscopy was applied to observe the growth of the organoids and analyze the number,average diameter,and total area.Then,organoids cultured alone served as the control group.After the control and co-culture groups were treated with chemotherapy drugs,5-fluorouracil and oxaliplatin,for 48 h,the viability and apoptosis of organoids were assessed with CellTiter-Glo??3D assay and CellEvent? Caspase 3/7 activity,respectively.Results Gastric cancer organoids and CAFs were successfully established from 10 gastric cancer patient-derived samples.The gastric cancer organoids exhibited morphological characteristics consistent with the corresponding primary tumors,and showed positive expression of CK7,CEA,and Ki-67.CAFs displayed typical spindle-shaped morphology and exhibited the phenotypic markers CD326-,CD45-,CD31-,α-SMA+,CD73+,CD90+,and CD105+.Compared to the organoids cultured alone,the organoids co-cultured with CAFs showed more formation of organoids,in larger average diameter,and taking larger total area(P<0.05).After the treatment of 5-fluorouracil and oxaliplatin,the half-maximal inhibitory concentration(IC50)was 10.66 and 3.26 μmol/L,respectively in the control group,while was 46.23 and 91.11 μmol/L in the co-culture group.Additionally,the number of CellEvent? Caspase 3/7 positive apoptotic cells was significantly less in the co-culture group than the control group.Conclusion Compared with individually cultured gastric cancer organoids,the co-culture model of gastric cancer organoids and CAFs better simulates the pro-tumor proliferation and drug resistance effects of in vivo tumor microenvironment.

Objective To establish a mouse model of bronchiectasis with acute infection and evaluate the immunogenicity and protective effect of a self-assembling Pseudomonas aeruginosa(PA)nanoparticle vaccine rePO-FN based on fusion of PcrV-OprI(rePO)protein with self-assembling ferritin(Ferritin).Methods ① SPF-grade female C57BL/6 mice(aged 6～8 weeks,weighing 18～20 g)were randomly allocated into normal saline group,and low-,medium-and high-dose elastase groups(n=6).A mouse model of bronchiectasis was established via intratracheal instillation of different doses of elastase(30 μL of normal saline containing 0.65,1.30 and 2.60 IU elastase)for 3 consecutive days.At 14 and 21 d after modeling,ELISA and HE staining were performed respectively to detect the concentration of IL-6 and to observe pathological changes in lung tissue in order to confirm the modeling.② A recombinant plasmid encoding the gene of fusion protein rePO-FN was constructed and expressed in E.coli.The target protein was purified via affinity chromatography and renatured to obtain the desired protein.The physicochemical properties of the rePO-FN protein were characterized using SDS-PAGE protein gel electrophoresis,dynamic light scattering,molecular sieve chromatography,and transmission electron microscopy.③ C57BL/6J mice were randomly divided into PBS group,rePO group,rePO-FN group,and Ferritin group(n=10).The mice in the above groups were immunized intramuscularly with 100 μL PBS buffer alone or containing 10 μg of corresponding proteins on days 0,7,and 14.ELISA was used to measure the specific antibodies in serum.In 7 d after the final immunization,an acute PA infection model was used to compare the survival rates and bacterial colonization among the PBS,rePO,and rePO-FN groups.After establishing a bronchiectasis model by intratracheal instillation of 2.60 IU of elastase in C57BL/6J mice as described above,the mice were randomly divided into bronchiectasis PBS group,bronchiectasis rePO group,and bronchiectasis rePO-FN group(n=10).Immunization was conducted at the same dose and procedure as described above,in 21 d after bronchiectasis modeling.At the 7th d after the final immunization,an acute PA infection model was used to compare the survival rates and bacterial colonization among the groups.Results ①Repeated intratracheal instillation of elastase significantly increased the concentration of IL-6 in the lung tissue when compared to the content of the normal saline group(P＜0.05).Pathological observations revealed varying degrees of bronchial wall destruction,alveolar fusion,edema,neutrophil infiltration,and hemorrhage,with the severity increasing with elastase dose,which confirming successful establishment of the mouse model of bronchiectasis.② Well-dispersed rePO-FN nanoparticles were successfully prepared,with an average particle size of 91.28 nm,a Zeta potential of approximately-6.5 mV,and a polydispersity index(PDI)of 0.306.Molecular sieve chromatography determined the elution volume of rePO-FN protein to be 8.80 mL,corresponding to a molecular weight of approximately 1 400 kDa.③ Under acute PA XN-1 strain infection,the survival rate of the rePO-FN immunization group and the bronchiectasis rePO-FN immunization group were significantly higher than that of the PBS control group(P＜0.05).Additionally,bacterial colonization in the lung tissues was significantly lower in the rePO-FN immune group and the bronchiectasis rePO-FN immune group under acute PA XN-1 strain infection than that in the rePO group and the bronchiectasis rePO group(P＜0.05).Conclusion Our vaccine rePO-FN can effectively trigger a strong humoral immune response and provide significant protection against PA infection in a mouse bronchiectasis model.

OBJECTIVE Aimed at investigating whether reflux pharyngitis is an independent risk factor for the failure of type Ⅰ tympanoplasty for chronic otitis media.This is achieved by analyzing the relationship between the postoperative tympanic membrane healing in patients who underwent type Ⅰ tympanoplasty and pharyngolaryngeal reflux finding score(RFS).METHODS Patients who underwent type Ⅰ tympanoplasty in the Department of Otolaryngology Head and Neck Surgery,Nanshan People's Hospital,Shenzhen,China,from January 2023 to July 2024 were retrospectively included.All the patients received preoperative perfect nasal endoscopy,laryngoscopy,evaluation by the RFS questionnaire,preoperative otoscopy for tympanoplasty,pure tone hearing threshold,and temporal bone thin-layer CT examination.Postoperative otoscopic examination was performed to observe tympanic membrane healing and followed up for 3 months.The patients were divided into surgery success group and failure group based on the criterion of whether a complete tympanic membrane was formed by endoscopic examination within 3 months.The RFS scores of the two groups were statistically analyzed.RESULTS A total of 135 patients with an average age of 44.78 years(±12.22 years)took part in this study,with 60 males and 75 females included,and 68 left ears and 67 right ears involved.There were 120 patients in the surgery success group,and 15 patients in the failure group.Statistical analysis revealed that the RFS score of the patients in the tympanoplasty failure group was remarkably higher than that of the patients in the tympanoplasty success group.Moreover,there were significantly more cases with suspected reflux pharyngitis in the surgery failure group(P=0.007).Reflux-induced tympanic membrane lesion and reperforation mostly occurred in the central part of the tympanic membrane graft.CONCLUSION Reflux pharyngitis has been implicated with tympanoplasty failure,and thus may be a causative factor.Additionally,the RFS can be used to screen patients with chronic suppurative otitis media for suspected reflux pharyngitis.Findings from this work indicate that perioperative anti-reflux therapy,combined with dietary and lifestyle counselling for the patients who suffer from reflux pharyngitis and are about to undergo the tympanoplasty surgery may improve surgical success rate.

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal-derived tumors of the gastrointestinal tract. Tyrosine kinase inhibitors (TKIs) are the cornerstone of GIST therapy, but mutations in resistance genes pose many problems for treatment, especially the heterogeneity of KIT resistance mutations. In recent years, with the release of a number of GIST related drug research and experimental results, the great potential of targeted therapy, immunotherapy and combination therapy to treat GIST in different directions has been revealed, providing more therapeutic directions for GIST. This article will review the experimental research and future direction in recent years.

Objective To establish a high-throughput screening system to obtain key Staphylococcus aureus (S.aureus)secretory proteins which required for S.aureus survival in macrophages.Methods Based on our validated eukaryotic expression vector library of S.aureus secretory proteins,DNA transfection was used to obtain an RAW264.7 macrophage array expressing S.aureus secretory proteins.After the RAW264.7 cells were infected with S.aureus,the extracellular bacteria were removed to observe the intracellular surviving situation of S.aureus.Finally,the screening results were validated by the overexpression and knockout S.aureus of corresponding secretory proteins.Results The optimal transfection dose (1.0 μg/well)of plasmids for RAW264.7,multiplicity of infection (MOI,1 .0 ),and infection time (4 h after removing extracellular bacteria of S.aureus ) were established respectively.To validate the screening results,the corresponding overexpression and knockout strains were constructed.And hypothetical protein and Serine protease E were found to promote the survival of intracellular S.aureus.Conclusion We successfully construct a screening system for key secreted secretory proteins which required for S.aureus surviving in macrophages,which may advance the study of the intracellular surviving mechanism of S.aureus.

Objective To investigate the distribution of B cells in both tumor and non-tumor tissues of gastric cancer patients,analyze their phenotypic characteristics and explore the impact on T cell proliferation.Methods Immunohistochemical staining was utilized to detect the expression of B cell surface marker CD 19 in tumor and non-tumor tissues from 33 gastric cancer patients.The expression levels of chemokine receptors and immunoglobulin molecules on B cells in both tumor and non-tumor tissues were measured using flow cytometry.Chemotaxis experiments were conducted to examine the role of the CXCL12-CXCR4 axis in B cell chemotaxis.B cells isolated and purified from both tissue types were co-cultured with autologous peripheral T cells to assess their effect on T cell proliferation.Results There were significantly more B cells infiltrated in tumor tissues than those infitrated in the non-tumor tissues of gastric cancer patients(P＜0.01),and CXCR4 was highly expressed on tumor-infiltrating B cells compared with B cells derived from non-tumor tissues(P＜0.05).The Cancer Genome Atlas(TCGA)analysis indicated that the expression level of CXCL12 in tumor tissues was positively correlated with the expression level of CD19 in gastric cancer patients(r=0.15,P＜0.01).And the expression level of CXCL12 in tumor tissues of the gastric cancer patients was also positively correlated with the number of B cells infiltrated in tumor tissues.Chemotaxis experiments confirmed that the CXCL12-CXCR4 axis was involved in promoting B cell chemotaxis(P＜0.05).Although B cells in tumor and non-tumor tissues had similar levels of IgM,IgG,and IgA expression,tumor-infiltrating B cells significantly inhibited the proliferation of T cells when compared with B cells derived from non-tumor tissues(P＜0.01).Conclusion There are more B cells infiltrated in gastric cancer tissues,which may be recruited to tumor tissues through the CXCL12-CXCR4 axis,and then inhibit T cell proliferation to promote the progression of gastric cancer.

Objective To explore the mechanism which drives nimbolide(NIM)in treating acute pneumonia caused by Staphylococcus aureus(S.auteus).Methods A mouse model of acute pneumonia caused by S.auteus was constructed through endotracheal intubation.After NIM treatment,the survival rate was observed,the amount of bacteria in the lung was tested by plate culture,and the expression of inflammatory cytokines in the lung tissues was detected with ELISA.After primary cultured peritoneal macrophages(PM)were infected with S.auteus,the effect of NIM on the expression of inflammatory cytokines and activation of inflammatory pathway were studied with ELISA and Western blotting,respectively.The effect of RNF114 knockdown by lentiviral shRNA infection on inflammation responses in PM was explored with ELISA and Western blotting.Results Acute infection of S.auteus in the lung could cause acute death in the mice,while NIM treatment significantly improved the survival rate and down-regulated the levels of inflammatory cytokines in the lung.However,it had no effect on the lung colonization of S.auteus in the short term.The results of in vitro experiments indicated that NIM may regulate RNF114 function to down-regulate the phosphorylation level of ERK,inhibit the activation of MAPK pathway,and thus suppress the expression of inflammatory cytokines.Conclusion NIM may inhibit the activation of MAPK pathway by regulating the function of RNF114,and thus suppress the expression of inflammatory cytokines in the lung,and finally inhibit the death of mice with acute pulmonary hyperinflammation caused by S.auteus.

Biotechnological Pharmaceutics is a compulsory course for biotechnology undergraduates in our school. We designed and implemented an elective course named Structural Biology to help students master technological principles through practice. This elective course included in-classroom lectures and experiments; during which we encouraged students to work together, and design, prepare, implement, and complete projects; examination score of Biotechnological Pharmaceutics was used to assess learning outcomes. The results showed that students who took this course gained higher score in the examination, indicating that the elective course is effective to improve the learning effect of Biotechnological Pharmaceutics for biotechnology undergraduates.

Objective: Positron emission tomography-computed tomography (PET-CT) has been used to quantify inflammatory response in the body. The aim of the present study was to explore the possibility of using this method to evaluate the stability of atherosclerotic plaques and the efficacy of atorvastatin in stabilizing atherosclerotic plaques. Methods: Twenty New Zealand male white rabbits were included and divided into the atorvastatin intervention group and the control group, with 10 rabbits in each group. Rabbits in both groups were fed with a high fat diet for 20 weeks, and treated with thoracoabdominal aortic balloon-pulling to establish atherosclerosis model at the end of the 2nd week. Rabbits in atorvastatin intervention group was given atorvastatin intragastrically once a day. At the 8th week, thoracoabdominal aortic ultrasound was used to detect plaques in all rabbits. Blood was drawn at the 3rd and the 20th week, respectively, to measure blood lipids, high-sensitive C-reactive protein (hs-CRP) and matrix metalloproteinase-9 (MMP-9). At the end of experiment, survival animals were scanned by ¹⁸F-FDG PET-CT, and the average and maximum standard uptake values (SUVmean, SUVmax) of aortic segments were measured. Thereafter, the animals were sacrificed and aortic specimens of rabbits were taken and examined by immunohistochemistry. The pathological indexes were measured and compared. Results: At the end of experiment, the total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), hs-CRP [ (4.58±0.51) ng/ml vs.(5.87±0.66) ng/ml, P<0.01], MMP-9[ (43.93±2.16) ng/ml vs. (50.77±2.32) ng/ml, P<0.01], SUVmean (0.59±0.15 vs. 0.68±0.20, P<0.05) , SUVmax (0.68±0.20 vs. 0.81±0.27, P<0.05) , plaque area [ (0.36±0.24) mm² vs. (0.50±0.34) mm², P<0.05) ] and density of macrophage[ (4.34±1.54) % vs. (5.65±1.89) %, P<0.01] in the atorvastatin intervention group were significantly lower than those in the control group. In contrast, fiber cap thickness of the plaque[ (4.12±0.66) μm vs. (2.96±0.37) μm, P<0.01] in the atorvastatin intervention group was higher than that of the control group, and the difference was statistically significant. The arterial plaque areas were positively correlated with SUVmean (r=0.27, P<0.05) and SUVmax (r=0.43, P<0.01) . Fiber cap thickness was negatively correlated with SUVmean (r=-0.38, P<0.05) and SUVmax (r=-0.47, P<0.01) . The density of macrophage were positively correlated with SUVmean (r=0.52, P<0.01) and SUVmax (r=0.51, P<0.01) . Conclusion ¹⁸F-FDG PET/CT can be used to evaluate the efficacy of atorvastatin by the stability of atherosclerotic plaques.

With the rapid development of modern equipment and widespread familiarity with the relative knowledge, endoscopic ear surgery has attracted many oto-surgeons and is becoming more popular in primary hospitals in China. Standardized management of perioperative period in this field can help surgeons shorten the learning curve and avoid potential complications in endoscopic ear surgery. In this article, the management technique was introduced in detail, covering five main aspects including handling of related in-struments, preoperative examination and preparation, informed consent, preparation for patients and operation room setup. Extra focus was placed on the manipulation and resolution of possible difficulties during the procedure.