Objective:To discuss the regulatory effect of physiological tensile stress on the differentiation of chondrocytes,and to clarify the associated signaling pathway mechanism.Methods:The ATDC5 chondrocytes were cultured in vitro and subjected to physiological tensile stress by four-point bending cell mechanical loading device.Initially,the cells were divided into control group and tensile stress group(2 000 μstrain/2 h group),and further divided into different stress magnitudes(1 000,2 000,and 3 000 μstrain)for 2 h,and 2 000 μstrain for different duration time(1,2,and 4 h)groups;the cells without tensile stress were used as control group.Real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the expression levels of type Ⅱ collagen(Col-Ⅱ),type Ⅹ collagen(Col-Ⅹ),aggregated proteoglycom(Aggrecan),sex-determining region Y-box protein 9(SOX9),vascular endothelial growth factor(VEGF),proliferating cell nuclear antigen(PCNA),Nel-like molecule tyep 1(Nell-1),Runt-related transcription factor 2(Runx2),Indian hedgehog(Ihh),patched homolog 1(Ptch-1),GLI family zinc finger protein 1(Gli-1),and hedgehog interacting protein 1(Hhip-1)mRNA in the cells in various groups;Western blotting method was used to detect the expression levels of Nell-1,Runx2,and Ihh proteins in the cells in various groups.The ATDC5 cells were divided into control group,cyclopamine group,tensile stress group,and cyclopamine + tensile stress group.RT-qPCR method was used to detect the expression levels of Nell-1,Ihh,Ptch-1,Gli-1,and Hhip-1 mRNA in the cells in various groups;Western blotting method was used to detect the expression levels of Nell-1 and Ihh proteins in the cells in various groups.Results:Compared with control group,the expression levels of Col-Ⅱ,Col-Ⅹ,Aggrecan,SOX9,VEGF,and PCNA mRNA in the cells in 2 000 μstrain/2 h group were significantly increased(P<0.01);after treated with 2 000 μstrain tensile stress for different duration time(1,2,and 4 h)or different tensile stresses(1 000,2 000,and 3 000 μstrain)for 2 h,compared with control group,the expression levels of Runx2 mRNA in the cells in other groups were increased with the prolongation of time or the increasing of tensile stress(P<0.01),and the expression levels of Nell-1,Ihh,Ptch-1,Gli-1,and Hhip-1 mRNA were gradually increased(P<0.01),the expression levels reached the peaking at 2 000 μstrain/2 h,and then decreased but remained significantly higher than that in control group(P<0.01).The Western blotting results showed that the expression levels of Nell-1,Runx2,and Ihh proteins in the cells were consistent with the change trend of mRNA expression levels.After pre-treated with cyclopamine,compared with control group,the expression levels of Ihh,Ptch-1,Gli-1,and Hhip-1 mRNA in the cells in cyclopamine group were significantly decreased(P<0.01),and the expression levels of Ihh,Ptch-1,Gli-1,and Hhip-1 mRNA in the cells in tensile stress and cyclopamine+tensile stress groups were significantly increased(P<0.01);compared with cyclopamine group,the expression levels of Nell-1,Ihh,Ptch-1,Gli-1,and Hhip-1 mRNA in the cells in cyclopamine+tensile stress group were significantly increased(P<0.01);compared with tensile stress group,the expression levels of Ihh,Ptch-1,Gli-1,and Hhip-1 mRNA in the cells in cyclopamine + tensile stress group were significantly decreased(P<0.01).Compared with control group,the expression level of Ihh protein in the cells in cyclopamine group was significantly decreased(P<0.01),but there was no significant difference in expression level of Nell-1 protein in the cells between control group and cyclopamine group(P>0.05),while the expression levels of Nell-1 and Ihh proteins in the cells in tensile stress group and cyclopamine + tensile stress group were significantly increased(P<0.01);compared with cyclopamine group,the expression levels of Nell-1 and Ihh proteins in the cells in tensile stress group and cyclopamine + tensile stress group were significantly increased(P<0.01);compared with tensile stress group,in the expression levels of Nell-1 and Ihh proteins in the cells in cyclopamine + tensile stress group had no significant differences(P>0.05).Conclusion:After stimulated with physiological tensile stress,Nell-1 can activate the Ihh signaling pathway upstream,and regulate the differentiation of the ATDC5 chondrocytes.

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant solid tumor of the digestive system, characterized by rapid progression and difficulties of early diagnosis. Five-year survival rate of the patients is less than 9%. With the acceleration of global population aging and lifestyle change, the incidence of PDAC has been increasing annually. Currently, surgical treatment and chemotherapy remain the standard treatment options for PDAC patients. Early symptoms of PDAC are so undetectable that most patients miss the optimal opportunity for radical surgical resection. Even among those who undergo surgery, the high recurrence rate remains a major problem. PDAC is known for its unique tumor microenvironment. The cellular and non-cellular components in the tumor microenvironment account for as much as 90% of the tumor stroma, presenting many potential targets for PDAC therapy. Activated pancreatic stellate cells within PDAC tissue express specific proteins and secrete various cytokines and metabolites, which directly contribute to the proliferation, invasion, and metastasis of PDAC cells. These elements are critical in extracellular matrix production, connective tissue hyperplasia, immune tolerance, and drug resistance. Immune cells, such as macrophages and neutrophils, exert immunosuppressive and tumor-promoting roles in PDAC progression. The extracellular matrix, which serve as a natural physical barrier, induces interstitial hypertension and reduces blood supply, thereby hindering the delivery of drugs to the tumor. Additionally, it helps the metastasis and differentiation of PDAC cells, reducing the efficacy of clinical chemotherapy and immunotherapy. Although chemotherapeutic agents like gemcitabine have been used in the clinical treatment of PDAC for more than 20 years, the curative effect is obstructed by their poor stability in the bloodstream, low cellular uptake, and poor targeting. While small-molecule inhibitors targeting mutations such as KRAS^G12C, BRCA, and NTRK fusion have shown great potential for molecular targeted treatments and gene therapies of PDAC, their broader application is limited by side effects and restricted scope of patients. The advancement of nanotechnology brings new strategies for PDAC treatment. By virtue of unique size characteristics and actual versatility, different drug-delivery nanosystems contribute to overcome the dense stromal barrier, prolong the circulation time of therapeutics and realize precise PDAC treatment by targeted drug delivery. Clinical nanodrugs such as albumin-bound paclitaxel (nab-paclitaxel) and irinotecan liposome greatly improve the pharmacokinetics of conventional chemotherapeutics and promote drug accumulation inside the tumor, thereby are applying to the first-line treatment of PDAC. It is noteworthy that none nanodrugs with active targeting design have been approved for clinical treatment yet, though many are in clinical trials. In this review, we discuss promising targeting strategies based on different nanodrug delivery systems for treatment of PDAC. One major nanostrategy focuses on the tumor cell targeting and its applications in chemotherapy, molecular targeting therapy, gene therapy, and immunotherapy of PDAC. Another nanostrategy targets the tumor microenvironment, which highlights the nanosystems specifically regulating pancreatic stellate cells, immune cells and the extracellular matrix. Recent progress of developing new nanotheraputics for breakthrough in the fight of PDAC are elaborated in this review. We also provide our perspectives on the challenges and opportunities in the field.

Objective To evaluate the value of miniprobe endoscopic ultrasound(EUS)in guiding endoscopic treatment of small-diameter(maximum diameter less than 1 cm)and low-grade(G1 grade)rectum neuroendocrine neoplasm(R-NEN),and to provide evidence and clues for its clinical application and further research.Methods The clinical data of 85 cases of low-grade(G1 grade)R-NEN with a maximum diameter of less than 1 cm who underwent endoscopic treatment in our center from January 2014 to December 2020 were retrospectively analyzed.The patients were divided into the EUS group(37 cases)and control group(48 cases)according to whether EUS was performed before endoscopic treatment.The positive rate of incision margin,the incidence of complications,the recurrence rate,the hospital stay,the cost of hospitalization and endoscopic therapy were compared between the two groups.Results The positive rate of incision margin in the EUS group was significantly lower than that in control group(P<0.05).There was no significant difference in the incidence of complications,tumor recurrence rate,hospital stay or hospital costs between the two groups(P>0.05).There was statistically significant difference in the endoscopic therapy between the two groups(P<0.05).Conclusion Evaluating the lesion depth of small-diameter and low-grade(G1 grade)R-NEN before surgery by miniprobe EUS and selecting endoscopic surgery according to its results of can significantly reduce the residual risk of resection margin tumors.

Humans ; Proto-Oncogene Proteins p21(ras)/genetics* ; Prognosis ; Biomarkers, Tumor/genetics* ; Mutation/genetics* ; Colorectal Neoplasms/genetics* ; Proto-Oncogene Proteins B-raf/metabolism*

Objective To observe the influence of nintedanib ethanesulfonate soft capsules combined with tetrandrine tablets on pulmonary function and dyspnea symptoms in patients with connective tissue disease-related pulmonary interstitial fibrosis.Methods Patients with connective tissue disease-related pulmonary interstitial fibrosis were divided into treatment group and control group by cohort method.The control group was given basic treatment such as glucocorticoids and immunosuppressants according to the patient's condition;the treatment group was given ethanesulfonate nintedanib soft capsules(100 mg,bid)and tetrandrine tablets(40 mg,tid)on the basis of the control group,and the treatment course was 3 months.The clinical efficacy,severity of dyspnea[modified British Medical Research Council Dyspnea Scale(mMRC)and St.George's Respiratory Questionnaire(SGRQ)],pulmonary function indicators,pulmonary fibrosis score,and blood gas analysis indicators were compared between the two groups,and the safety was assessed.Results A total of 42 cases were included in the treatment group and the control group,respectively.The total effective rates of the treatment group and the control group were 92.86％(39 cases/42 cases)and 76.19％(32 cases/42 cases)respectively(P＜0.05).After treatment,the mMRC scores of the treatment group and the control group were(1.43±0.27)and(1.69±0.31)points;the SGRQ scores were(46.51±4.39)and(51.08±4.76)points;the forced expiratory volume in one second(FEV1)values were(64.96±6.55)％and(58.67±5.01)％;the fibrosis scores were(1.12±0.14)and(1.26±0.18)points;the partial pressure of arterial oxygen values were(80.31±7.03)and(75.02±6.94)mmHg.The above indexes of the treatment group were compared with those of the control group,and the differences were statistically significant(all P＜0.05).There were no adverse drug reactions in the treatment group,and the main adverse drug reactions in the control group were gastrointestinal discomfort.The total incidence rates of adverse drug reactions in the treatment group and the control group were 0 and 2.38％,respectively(P＞0.05).Conclusion Compared with basic treatment,nintedanib ethanesulfonate soft capsules combined with tetrandrine tablets can better improve the pulmonary fibrosis degree and dyspnea degree in patients with connective tissue disease-related pulmonary interstitial fibrosis,and delay the decline of pulmonary function of patients.

Objective:To study the effects of periodontitis on bone and tryptophan metabolism of gut microbiota in the context of estrogen deficiency.Methods:Thirty-two female C57BL6/J mice were randomly divided into four groups based on table of random numbers ( n=8 in each group): Sham group, in which mice were given sham surgery; Sham_Lig group, in which mice were given sham surgery and were induced to periodontitis by ligating the bilateral maxillary second molars with 5-0 silk threads at the fourth week; Ovx group, in which mice were given bilateral ovariectomy; Ovx_Lig group, in which mice were given bilateral ovariectomy and were induced to periodontitis at the fourth week. After 8 weeks of ligation, the mice of 4 groups were euthanized for collecting the samples of femur, tibia, mandible and skull. Those samples were scanned by micro-CT to measure the bone mineral density (BMD), bone volume versus total volume ratio (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th) and trabecular spacing (Tb.Sp). The cecum contents of 4 groups of mice were collected for gut microbiota 16S rRNA gene sequencing. The tryptophan and its metabolites in intestinal tracts were detected by liquid chromatography-mass spectrometry. Pearson correlation analysis was performed to analyze the correlation between the abundance of gut microbiota and the content of tryptophan and its metabolites. Results:Femur BMD [(82.23±3.97) mg/cm 3], BV/TV [(9.25±1.37)%] and Tb.Th [(70.95±5.70) μm] in Ovx_Lig group were significantly lower than Ovx group [(96.30±3.76) mg/cm 3 ( P=0.004); (14.45±1.55)% ( P=0.022) and (87.58±8.02) μm ( P<0.001), respectively]. The β-diversity analysis of gut microbiota based on Bray-Curtis distance showed that samples of Ovx_Lig group and Ovx group were obviously grouped. Linear discriminant analysis effect size (LEfSe) showed that Alistipes was the representative genus in Ovx_Lig group. The relative abundance of Alistipes in Ovx_Lig group [(0.42±0.14)%] were significantly higher than that in Ovx group [(0.17±0.05)%] ( t=4.45, P<0.001). Tryptophan metabolism analysis showed that the content of kynurenic acid [(531.12±158.60) ng/g] in Ovx_Lig group were significantly higher than that in Ovx group [(400.42±57.96) ng/g] ( t=2.19, P=0.046). And the content of indole-3-carbaldehyde [(383.37±144.06) ng/g] in Ovx_Lig group were significantly lower than Ovx group [(701.72±141.93) ng/g] ( t=4.45, P<0.001). Correlation analysis showed that relative abundance of Alistipes was positively correlated with kynurenic acid ( r=0.32, P=0.088), while negatively correlated with indole-3-carbaldehyde ( r=-0.32, P=0.088). Conclusions:Periodontitis can induce bone destruction of femur in estrogen-deficient mice, the mechanism of which may be related to Alistipes in gut and the tryptophan metabolites kynurenic acid and indole-3-carbaldehyde.

Objective To explore differentially expressed endoplasmic reticulum stress-associated genes(ERSAGs)in aortic dissection(AD)and their correlations with immune cell infiltration to identify new therapeutic targets for AD.Methods Two AD mRNA expression datasets(GSE190635 and GSE98770)were downloaded from GEO database for analysis of differentially expressed genes between the aorta of AD patients and normal aorta using R software.ERSAGs dataset was downloaded from GeneCards website,and GeneMANIA database was used to analyze the protein-protein interaction network of the differentially expressed ERSAGs and the proteins interacting with these genes.Based on GSE98770 dataset we analyzed the distributions of 22 immune cells within the aortic wall of AD patients using CIBERSORT package of R software.Surgical aortic wall specimens were obtained from 10 AD patients and 10 non-AD patients for detecting AGER mRNA expression using qRT-PCR,and the upstream transcriptional factors,miRNAs,and chemicals targeting AGER were analyzed using the TRRUST database and NetworkAnalyst database.Results Bioinformatic analysis suggested significant differential expression of AGER in AD,which interacted with 20 proteins involved in pattern recognition receptor signaling pathway,positive regulation of DNA-binding transcription factor activity,myeloid leukocyte migration,leukocyte migration,and regulation of the I-κB kinase/NF-κB signaling.In AD,AGER expression level was positively correlated with Treg cell abundance(r=0.59,P<0.05).The results of qRT-PCR demonstrated significantly lower expression of AGER mRNA in AD than in non-AD patients(1.00±0.30 vs 1.76±0.68,P<0.05).ROC curve analysis showed that at the cut-off value of 1.335,AGER had an AUC of 0.86(95%CI:0.67-1.00,P=0.0073)for predicting AD.Three transcriptional factors,3 miRNAs,and 27 chemicals were predicted in the AGER regulatory network.Conclusion AGER is lowly expressed in the aorta of AD patients and may influence the occurrence of AD through Treg cells.

The incidence of early-onset gastric cancer (EOGC) is consistently increasing, and its etiology is notably complex. This increase may be attributed to distinctive factors that differ from those associated with late-onset gastric cancer (LOGC), including genetic predispositions, dietary factors, gastric microbiota dysbiosis, and screening of high-risk cases. These factors collectively contribute to the onset of cancer. EOGC significantly differs from LOGC in terms of clinicopathological and molecular characteristics. Moreover, multiple differences in prognosis and clinical management also exist. This study aimed to systematically review the latest research advancements in the epidemiological characteristics, etiological factors, clinicopathological and molecular features, prognosis, and treatment modalities of EOGC.

Objective Viral encephalitis is an infectious disease severely affecting human health.It is caused by a wide variety of viral pathogens,including herpes viruses,flaviviruses,enteroviruses,and other viruses.The laboratory diagnosis of viral encephalitis is a worldwide challenge.Recently,high-throughput sequencing technology has provided new tools for diagnosing central nervous system infections.Thus,In this study,we established a multipathogen detection platform for viral encephalitis based on amplicon sequencing. Methods We designed nine pairs of specific polymerase chain reaction(PCR)primers for the 12 viruses by reviewing the relevant literature.The detection ability of the primers was verified by software simulation and the detection of known positive samples.Amplicon sequencing was used to validate the samples,and consistency was compared with Sanger sequencing. Results The results showed that the target sequences of various pathogens were obtained at a coverage depth level greater than 20×,and the sequence lengths were consistent with the sizes of the predicted amplicons.The sequences were verified using the National Center for Biotechnology Information BLAST,and all results were consistent with the results of Sanger sequencing. Conclusion Amplicon-based high-throughput sequencing technology is feasible as a supplementary method for the pathogenic detection of viral encephalitis.It is also a useful tool for the high-volume screening of clinical samples.

Objective In this study,we analyzed the transcriptome sequences of Kupffer cells exposed to simulated microgravity for 3 d and conducted biological experiments to determine how microgravity initiates apoptosis in Kupffer cells. Methods Rotary cell culture system was used to construct a simulated microgravity model.GO and KEGG analyses were conducted using the DAVID database.GSEA was performed using the R language.The STRING database was used to conduct PPI analysis.qPCR was used to measure the IL1B,TNFA,CASP3,CASP9,and BCL2L11 mRNA expressions.Western Blotting was performed to detect the level of proteins CASP3 and CASP 9.Flow cytometry was used to detect apoptosis and mitochondrial membrane cells.Transmission electron microscopy was used to detect changes in the ultrastructure of Kupffer cells. Results Transcriptome Sequencing indicated that simulated microgravity affected apoptosis and the inflammatory state of Kupffer cells.Simulated microgravity improved the CASP3,CASP9,and BCL2L11 expressions in Kupffer cells.Annexin-V/PI and JC-1 assays showed that simulated microgravity promoted apoptosis in Kupffer cells.Simulated microgravity causes M1 polarization in Kupffer cells. Conclusion Our study found that simulated microgravity facilitated the apoptosis of Kupffer cells through the mitochondrial pathway and activated Kupffer cells into M1 polarization,which can secrete TNFA to promote apoptosis.