Thymocyte selection-associated high mobility group box (TOX), a member of the high mobility group protein super-family, plays an important role in T cell development, functional maintenance, and exhaustion. It has been recently found that TOX exerts critical immunoregulatory functions during pathogen infections, and TOX expression is strongly associated with the intensity and tolerance of host immune responses. This review systematically summarizes the structural and functional features of TOX and focuses on its expression dynamics, mechanisms of action, and immunomodulatory effects during viral, bacterial, and parasitic infections, which provides a theoretical support to better understanding of the role of TOX in infectious diseases and provides new insights into development of potential immunotherapeutic strategies targeting TOX.

Objective To map the genome-wide distribution profile of histone H3K27me3 modification in diffuse gastric cancer tissues,identify target genes regulated by H3K27me3,and primarily explore the potential mechanism of its modification reprogramming in the occurrence and development of the tumor.Methods Normal gastric mucosal tissues and diffuse gastric cancer tissues were harvested from the patients who underwent examinations or treatments in the departments of gastroenterology and gastrointestinal surgery of our medical center between 2021 and 2023.There were 14 patients in the normal group(6 males and 8 females,average age of 46 years)and 14 patients in the gastric cancer group(8 males and 6 females,average age of 63 years).Cleavage under target and tagmentation(CUT&Tag)technology was employed to capture genomic regions modified by H3K27me3,and analyze the reprogramming characteristics of these modifications.RNA sequencing data,data from high-throughput chromosome conformation capture(Hi-C)technology,and publicly available single-cell data were integrated to investigate the target genes regulated by the reprogramming of H3K27me3 modifications in diffuse gastric cancer cells.Results The quality of the CUT&Tag and RNA sequencing data met the standards required for subsequent analysis.Histone H3K27me3 modifications in normal gastric mucosa and diffuse gastric cancer tissues were primarily distributed in distal intergenic regions and intronic regions.In gastric cancer tissues,compared to normal tissues,there was significant reprogramming of H3K27me3 modifications,characterized by a marked reduction in overall H3K27me3 signal intensity.The loss of 2 912 H3K27me3 signal peaks might lead to the up-regulation of 822 tumor-associated genes.Among them,56 genes displayed the most significant up-regulation(fold change in signal intensity≥2,P<0.05),with notable enrichment in the mammalian target of rapamycin complex 1(mTORC1)signaling pathway.Specifically,the methionine transporter SLC7A5 and the cystine transporter SLC7A11 were found to have the highest expression levels in gastric cancer tissues.Single-cell data revealed that the abnormal overexpression of SLC7A11 in diffuse gastric cancer was primarily observed in tumor epithelial cells.Further validation using public data and immunohistochemical experiments confirmed the elevated expression of SLC7A11 in diffuse gastric cancer,which is associated with poor prognosis in gastric cancer patients.Conclusion The reprogramming of histone H3K27me3 modification is an important epigenetic characteristic in diffuse gastric cancer.Loss of H3K27me3 signal peaks may up-regulate the expression of SLC7A11 in diffuse gastric cancer cells,and thereby promote tumor progression.

Objective To draw the genome-wide distribution and remodeling characteristics of H3K27me3 silencers in signet-ring cell carcinoma of the stomach(SRCC)through epigenetic sequencing technology,and to investigate their roles in transcriptional regulation in order to elucidate the regulatory mechanism of SRCC malignant progression.Methods The study was conducted on 35 gastric samples obtained by gastroendoscopic biopsy(15 normal and 20 SRCC tissues)from Department of Gastroenterology of Army Medical Center of PLA between January 2021 and December 2023.Multi-omics analyses,including assay for transposase-accessible chromatin with high-throughput sequencing(ATAC-seq),cleavage under targets and tagmentation(CUT&Tag)and transcriptome sequencing(RNA-seq),were performed to identify chromatin accessibility,H3K27me3 silencer regions,and transcriptional changes,with aid of Illumina NovaSeq 6000.H3K27me3 related differentially expressed genes(|Log2FC|>1,FDR<0.05)were screened using DESeq2.Gene Ontology(GO)analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis were employed to analyze the enrichment function,and Homer was employed to identify transcription factor motifs.A regulatory network was constructed using Cytoscape,and then validated using immunohistochemistry to explore its regulatory mechanism.Results H3K27me3 silencers were primarily located in distal intergenic regions(37.06%)in SRCC.Compared with the normal tissues,SRCC showed a significant reduction in H3K27me3 silencer signals(95%CI:1.34～2.30,P=0.007)with 6 257 lost sites(FDR<0.01).Integrating CUT&Tag and RNA-seq revealed 380 up-regulated immune-related genes,particularly in T cell receptor signaling(OR=4.2,95%CI:2.8～6.3,P=0.002).Immunohistochemistry confirmed elevated expression of transcription factor EHF(P<0.05).Conclusion There is the remodeling of H3K27me3 silencers in SRCC,and EHF may potentially play a crucial role in the SRCC malignant progression.

BACKGROUND:The formation of Lewy bodies due to abnormal α-synuclein aggregation is a characteristic pathological change in Parkinson's disease.In recent years,several studies have revealed that the formation of α-synuclein aggregates is closely related to its post-translational modifications.The modification of α-synuclein such as phosphorylation,nitration,acetylation,and ubiquitination has attracted extensive attention in the pathogenesis and progression of Parkinson's disease. OBJECTIVE:To review the research progress in the effect of modification types and sites of α-synuclein on the characteristic pathological formation and progression of Parkinson's disease. METHODS:PubMed and CNKI databases were searched by the first author with the key words of"α-synuclein,Parkinson's disease,phosphorylation,acetylation,ubiquitination,nitration"in English and Chinese respectively to collect and sort out the literature related to abnormal modification of α-synuclein in recent years.Finally,61 articles were included for further review. RESULTS AND CONCLUSION:Abnormal modification of α-synuclein is closely related to its protein structure and its positive and negative charges.Its amino terminus is positively charged and prone to ubiquitination and acetylation modifications.The central hydrophobic region is prone to forming β-pleated sheet due to its hydrophobic property.The carboxyl terminus is negatively charged,which is the main phosphorylation modification region.Phosphorylation modification sites promote phosphorylation modification and are closely related to α-synuclein aggregation,while protein kinases can target the activation of translational modifications,which may help to promote or inhibit aggregate formation.The degradation pathway of α-synuclein mainly plays a role in removing pathological proteins.Various kinase catalysts contribute to impaired protein ubiquitination modifications that lead to abnormal protein accumulation,thereby exacerbating neurodegeneration.The amino-terminal acetylation of α-synuclein improves the shuttle ability of the protein to the cell membrane and slows down the protein aggregation,which may be the protection target of nerve cells.However,the acetylation modification of the mutant protein produces the opposite effect.The protein nitration modification is mainly related to oxidative stress.The aggregation tendency of the protein modified by nitration is enhanced under the action of reactive oxygen species.Different post-translational modifications have different effects.Therefore,elucidating the main mechanisms of their post-translational modifications and inhibiting the post-translational modifications that contribute to protein aggregation may provide a reference for new targets for early diagnosis and treatment of Parkinson's disease.

BACKGROUND:C2 ceramide reduces the formation of Alpha-Synuclein(α-Syn)oligomers as the protein phosphatase 2A agonist,which has an important regulatory effect on cell aging in the central nervous system. OBJECTIVE:To investigate the protective mechanism of C2 ceramide on dopaminergic neurons. METHODS:Twenty-five C57BL/6 mice were randomly divided into control group,model group,C2 ceramide low-,medium-and high-dose groups(n=5 per group).Except for the control group,a mouse model of Parkinson's disease was established by injecting mutant A53T α-Syn oligomers into the left striatum in the other groups.On the 30th day after the striatal injection,three C2 ceramide groups were intragastrically administered with C2 ceramide(1,5,10 μg/g)dissolved in saline at one time,while the control and model groups were administered with the same amount of saline within 30-90 days after modeling,for a total of 60 days.Behavioral changes in each group of mice were observed during this period.On the 90th day after striatal injection,mouse brain tissue was extracted by perfusion under anesthesia,and the changes of dopaminergic neurons in the midbrain substantia nigra were analyzed by immunohistochemical staining.The levels of α-Syn oligomerization and phosphorylation in the midbrain of mice were detected by ELISA,and the changes of enzyme activities related to α-Syn phosphorylation were analyzed. RESULTS AND CONCLUSION:C2 ceramide had an ameliorating effect on Parkinson's disease-like dyskinesia in mice caused by the striatal injection of mutant A53T α-Syn oligomers.High-dose C2 ceramide showed better effects on dyskinesia in mice with Parkinson's disease(P<0.01).The mutant A53T α-Syn oligomers significantly reduced the number of dopaminergic neurons in the substantia nigra of mice(P<0.01),while the number of dopaminergic neurons in the substantia nigra increased significantly in the C2 ceramide high-dose group(P<0.01).The levels of α-Syn oligomers and phosphorylated α-Syn in the brain were significantly reduced in the C2 ceramide high-dose group compared with the model group(P<0.01),while the level of ceramide was increased(P<0.05)and the activity of protein phosphatase 2A was significantly upregulated(P<0.01).To conclude,C2 ceramide can attenuate the neurotoxic effects induced by oligomerized α-Syn by the phosphorylation modification environment of α-Syn in mouse midbrain tissue and protect against the reduction in the number of nigrostriatal dopaminergic neurons in mice,thereby reducing the degree of dyskinesia in Parkinson's disease.

Taking the Ligustrum lucidum extract as an example, this study investigated the influence of external mechanical forces under different processing conditions on the crystallographic solid form and the key parameter of drug dissolution rate, so as to provide guidance for the preparation and quality control of traditional Chinese medicine preparations. Under different pulverization and tableting conditions, the change of crystallographic solid form of L. lucidum extract was observed by polarizing light microscope. Meanwhile, the effect of this change on the dissolution rate was investigated, and the mathematical relationship between crystal content and dissolution rate was analyzed. The results showed that the process of ball milling and tableting had a significant impact on the crystallographic solid form of L. lucidum extract. The amorphous extract displayed crystal transformation, which induced a significant decline in dissolution rate. Further studies revealed that there was a negative linear relationship between crystal content and dissolution rate. The results of this study indicated that the crystallographic solid form transformation of traditional Chinese medicine extracts might occur during the preparation process, which may cause potential risks to the quality of traditional Chinese medicine preparations. It is suggested that we should pay attention to and strengthen the investigation of the crystallographic solid form during the preparation process, so as to guarantee the safety, effectiveness, and quality controllability of traditional Chinese medicine preparations.

Objective To explore prokaryotic expression,purification of hemolysin coregulatory protein(Hcp)of Vibrio cholerae,and preparation of its polyclonal antibodies.Methods PCR was used to amplify Vibrio cholerae Hcp gene and clone it into pET28a vector to construct recombinant expression vector.The recombinant vector pET28a-hcp was transformed into E.coil BL21(DE3)for expression condition optimization and expression form identification.The soluble Hcp protein was purified by Ni-NTA column.The purified Hcp protein was used to immunize BALB/c mice to prepare polyclonal antibodies.The antibody titer was detected by indirect enzyme-linked immunosorbent assay(ELISA)to evaluate its immunogenicity.Western blot was used to analyze the specific recognition of antibodies to Hcp protein in Vibrio cholerae.Results The enzyme fragment digested by recombinant vector pET28a-hcp was consistent with the expected,the sequencing results were consistent with the Hcp gene sequence in the GenBank database,and the pET28a-hcp recombinant plasmid was successfully constructed.The recombinant plasmid was induced by isopropyl-β-D-thiogalactopyranoside(IPTG)to express the target protein with a relative molecular weight of 28 kD.The pure Hcp protein was obtained after purification by Ni-NTA column,and then Hcp polyclonal antibody(anti-Hcp)with a titer of 1∶512 000 could be obtained from immunized mice.Western blot results showed that anti-Hcp had specificity in recognizing Hcp protein in Vibrio cholerae.Conclusion The soluble expression of Hcp protein is successfully obtained,and high-titer polyclonal antibodies against Hcp are obtained after immunization of mice,which may lay a foundation for subsequent studies on the role of Hcp protein in the pathogenesis of T6SS in non-O1/non-O139 V.cholerae.

Objective:To analyze the clinical features of anti-neurofascin-155 (NF155) antibody positive autoimmune nodopathy in children.Methods:This was a case series study. A total of 6 children who were diagnosed accurately as anti-NF155 antibody positive autoimmune nodopathy by cell immunofluorescence assay at the Children′s Hospital of Fudan University from January 2020 to December 2023 were collected. This study retrospectively analyzed 6 pediatric children′s clinical manifestations, laboratory and electrophysiological examination results, and treatment outcomes.Results:Among 6 children with anti-NF155 antibody positive autoimmune nodopathy, there were 4 boys and 2 girls. The onset age of 6 children ranged from 3 years and 8 months to 12 years. All 6 children had extremity weakness (more severe in the distal and the lower extremities than in the upper extremities), 5 children had sensory deficits such as numbness or pain in the extremities, 4 children had tremors and ataxia, 3 children had cranial nerve involvement. Among the 6 children, 4 children had protein-cell separation in cerebrospinal fluid examinations. Among the 6 children, 1 child had central nervous system demyelination, the brain magnetic resonance imaging showed multiple abnormal signals in the bilateral cerebral hemispheres. Four children showed motor and sensory nerve damage in electrophysiological examination, and 2 children only showed motor nerve damage. Three children showed myelin and axonal damage, and 3 children only showed axonal damage. Among the 6 children, 5 children were treated with intravenous immunoglobulin and steroids. Among them, 2 children underwent plasma exchange due to poor efficacy, and subsequently, rituximab was added. There was 1 child changed the treatment with olfatomumab since the symptoms did not significantly improve after using rituximab. After treatment for 4-15 months, 2 children had no clinical symptoms, 1 child had improvement in clinical symptoms, 2 children had no significant improvement in clinical symptoms, and 1 child who did not receive the immunotherapy had no significant change in clinical symptoms.Conclusions:Anti-NF155 antibody positive autoimmune nodopathy in children presents with varying degrees of clinical manifestations. It is mainly characterized by extremity weakness, numbness and pain, often accompanied bytremorsand ataxia. Some pediatric patients may also have central nervous system demyelination. Cerebrospinal fluid and electrophysiological examination are important auxiliary examination methods. If steroid therapy is not effective, plasma exchange and rituximab treatment should be used as soon as possible.

Objective:To investigate the CD163 expression characteristics in intracranial aneurysm (IA) tissue and blood of patients with IA and its feasibility as an early clinical screening indicator for IA.Methods:A total of 28 patients with IA admitted to Department of Neurosurgery, First Affiliated Hospital of Xinjiang Medical University from January 2021 to November 2023 were selected as IA group, and 28 healthy subjects from Health Management Center, First Affiliated Hospital of Xinjiang Medical University at the same time period were selected as control group. Eight saccular IA tissues and 12 superficial temporal artery tissues were collected from patients from IA group accepted IA clipping, and real-time fluorescent quantitative PCR (RT-qPCR) was used to detect the CD163 mRNA expression in these tissues. RT-qPCR was also used to detect the CD163 mRNA expression in the blood of the 2 groups. Seven patients with IA and 7 control subjects from the above 2 groups were randomly selected, respectively; and plasma CD163 protein content was detected by enzyme-linked immunosorbent assay (ELISA). Multivariate Logistic regression was used to analyze the influencing factors for IA. Receiver operating characteristic (ROC) curve was used to analyze the diagnostic values of blood CD163 mRNA expression and plasma CD163 protein content in IA. Results:CD163 mRNA expression in IA tissues was significantly higher than that in superficial temporal artery tissues (41.870±20.355 vs. 6.080±5.444, P<0.05). CD163 mRNA expression in the blood of IA patients was significantly higher than that in the controls (1.969[1.124, 2.318] vs. 1.124[0.933, 1.379], P<0.05). CD163 mRNA expression in the blood of ruptured IA group, unruptured IA group, and control group was gradually decreased, with significant differences ( P<0.05). CD163 mRNA expression in the blood of female IA patients was not statistically different compared with that in male IA patients ( P>0.05). ELISA showed that the CD163 protein content in plasma of the IA group was significantly higher than that in the control group [10.537±1.879] ng/L vs. [8.598±0.885] ng/L, P<0.05). Multivariate Logistic regression analysis showed that age and CD163 mRNA expression in the blood were independent influencing factors for IA occurrence ( OR=0.844, 95% CI: 0.750-0.951, P=0.005; OR=0.111, 95% CI: 0.024-0.506, P=0.004). ROC curve showed that the area under the curve (AUC) of CD163 mRNA expression in blood in diagnosing IA was 0.759 (95% CI: 0.618-0.890, P=0.002), and that of CD163 protein content in plasma in diagnosing IA was 0.864 (95% CI: 0.610-1.000, P=0.035). Conclusion:CD163 mRNA expressions in blood and IA tissues and CD163 protein content in plasma are high in patients with IA; CD163 mRNA expression in blood is an independent risk factor for IA; CD163 protein in plasma can be used as a molecular marker for screening IA.

Objective To establish and evaluate a gas chromatography-tandem mass spectrometry(GC-MS/MS)method for the detection of six common drugs(methamphetamine,meperidine,caffeine,codeine,cocaine and ketamine)in blood,and to improve the determination basis of results.Methods The above six drugs were added into the blank blood,and GC-MS/MS was used for detection after ether extraction.The collection,quantification and confirmation were carried out under the mode of multi-reaction monitoring(MRM).The qualitative results of the above six drugs were evaluated based on the maximum allowable deviation of the retention time and relative ion abundance ratio in the qualitative results of GC-MS/MS.Results There was a good linear relationship between the six common drugs,among which ketamine and caffeine had the lowest detection limit(0.01 μg/mL),methamphetamine had the highest detection limit(0.5 μg/mL).The retention time(RT)and relative retention time(RRT)of the target substance were stable under the six supplemental levels,and the absolute deviation(ΔRTabsolute)of RT was within±0.025 min.The absolute deviation of RRT(ΔRRTabsolute)was within±0.004.The relative ion abundance ratio absolute deviation(ΔIabsolute)is±20%,and the relative ion abundance ratio relative deviation(ΔIrelative)is±50%.Conclusion This study clarified the reference range for qualitative determination of six common drugs in blood matrix detected by GC-MS/MS,and effectively supplemented the qualitative determination indicators of existing instrumental analysis methods.