In the central nervous system (CNS), the myelin sheath, a specialized membrane structure that wraps around axons, is formed by oligodendrocytes through a highly coordinated spatiotemporal developmental program. The process begins with the directed differentiation of neural precursor cells into oligodendrocyte precursor cells (OPCs), followed by their migration, proliferation, differentiation, and maturation, ultimately leading to the formation of a multi-segmental myelin sheath structure. Recent single-cell sequencing research has revealed that this process involves the temporal regulation of over 200 key genes, with a regulatory network composed of transcription factors such as Sox10 and Olig2 playing a central role. The primary function of the myelin sheath is to accelerate nerve signal transmission and protect nerve fibers from damage. Its insulating properties not only increase nerve conduction speed by 50-100 times but also ensure the long-term functional integrity of the nervous system by maintaining axonal metabolic homeostasis and providing mechanical protection. The pathological effects of myelin sheath injury exhibit a cascade amplification pattern: acute demyelination leads to action potential conduction block, while chronic lesions may cause axonal damage and neuronal death in severe or long-term cases, ultimately resulting in irreversible neurological dysfunction with neurodegenerative characteristics. Multiple sclerosis (MS) is a neurodegenerative disease characterized by chronic inflammatory demyelination of the CNS. Clinically, the distribution of lesions in MS exhibits spatial heterogeneity, which is closely related to differences in the regenerative capacity of oligodendrocytes within the local microenvironment. Emerging evidence suggests that astrocytes form a dynamic “neural-immune-metabolic interface” and play a multidimensional regulatory role in myelin development and regeneration by forming heterogeneous populations composed of different subtypes. During embryonic development, astrocytes induce the targeted differentiation of OPCs in the ventricular region through the Wnt/β-catenin pathway. In the mature stage, they secrete platelet-derived growth factor AA (PDGF-AA) to establish a chemical gradient that guides the precise migration of OPCs along axonal bundles. Notably, astrocytes also provide crucial metabolic support by supplying energy substrates for high-energy myelin formation through the lactate shuttle mechanism. In addition, astrocytes play a dual role in myelin regulation. During the acute injury phase, reactive astrocytes establish a triple defense system within 72 h: upregulating glial fibrillary acidic protein (GFAP) to form scars that isolate lesions, activating the JAK-STAT3 regeneration pathway in oligodendrocytes via leukemia inhibitory factor (LIF), and releasing tumor necrosis factor-stimulated gene-6 (TSG-6) to inhibit excessive microglial activation. However, in chronic neurodegenerative diseases, the phenotypic transformation of astrocytes contributes to microenvironmental deterioration. The secretion of chondroitin sulfate proteoglycans (CSPGs) inhibits OPC migration via the RhoA/ROCK pathway, while the persistent release of reactive oxygen species (ROS) leads to mitochondrial dysfunction and the upregulation of complement C3-mediated synaptic pruning. This article reviews the mechanisms by which astrocytes regulate the development and regeneration of myelin sheaths in the CNS, with a focus on analyzing the multifaceted roles of astrocytes in this process. It emphasizes that astrocytes serve as central hubs in maintaining myelin homeostasis by establishing a metabolic microenvironment and signaling network, aiming to provide new therapeutic strategies for neurodegenerative diseases such as multiple sclerosis.

Aim Excessive cerebral inflammation caused by chronic alcohol intake is an important risk factor for central nervous system injury. The purpose of this study was to explore the protective effect of konjac mannan oligosaccharide (KMOS) on central nervous system inflammation in alcohol-fed mice and its mechanism. Methods The chronic alcohol fed model of C57BL/6J mice was established using Gao-binge method. And the different doses of KMOS were gavaged every day for 6 weeks. The neuronal damage and microglia activation were evaluated in cerebral cortex and hippocampus. The damage of colon tissue was assessed and serum LPS concentrations were measured. In vitro, Caco-2 cells were stimulated with LPS to establish intestinal mucosal injury model. Results Chronic alcohol intake can cause brain neuron damage in mice, and different doses of KMOS effectively reduced the activation state of microglia, decreased the expression of inflammatory factors caused by the activation of the NLRP3 inflammasome and alleviated neuronal damage in the brain tissue of alcohol-fed mice. The results of colon tissue analysis showed that the use of KMOS effectively reduced the concentration of endotoxin LPS in serum of alcohol-fed mice, alleviated the pathological injury and inflammatory response of colon tissue, and enhanced the expression of Occludin in intestinal tissue. In vitro experiments also showed that KMOS significantly inhibited the inflammatory reaction of Caco-2 cells exposed to alcohol and increased the expression of Occludin protein. Conclusions KMOS treatment effectively inhibited intestinal inflammation caused by alcohol intake, repaired intestinal barrier to prevent the entry of intestinal LPS into brain tissue, decreased the activation of microglia, and then improved brain neuron damage. KMOS had the potential to prevent alcoholic nerve injury.

Objective:To analyze the clinical and radiographic effectiveness of a calcium silicate-based bioactive ceramic iRoot BP Plus? pulpotomy of immature permanent teeth with complicated crown fracture and to evaluate the factors influencing its long-term success rate.Methods:The digital medical records of patients under 13 years old who had undergone iRoot BP Plus? pulpotomy in the Department of Oral Emergency or the First Clinical Division,Peking University School and Hospital of Stomatology from March 2017 to September 2022 due to complicated crown fracture of anterior teeth,and had taken at least one post-operation apical radiograph were reviewed.The clinical and radiographic information at the initial examination and follow-up period were obtained,including crown color,mobility,percussion,cold test(partial pulpotomy teeth),dental restoration,fistula,swelling or inflammation of the gingival tissue,the formation of apical foramen,pathologic radiolucency and calcification of pulp chamber or root canal obliteration.Data were tested by Fisher exact test and a multiple comparison.Results:In the study,64 patients including 37 males(57.8％)and 27 females(42.2％)with a mean age of 9.1 years were finally enrolled.The total number of permanent teeth that received pulpotomy was 75,and the average follow-up time was 19.3 months.The success rate was 93.1％with the time interval between dental injury and treatment in 24 h,while the success rate dropped to 88.2％with the time intervals beyond 24 h.The time intervals did not significantly affect the pulp survival rate(P=0.61)after pulpotomy(partial or co-ronal).The success rate 6 months after pulpotomy was 96.0％,and one-year success rate was 94.7％.A total of 23 cases were reviewed for more than 2 years after pulpotomy,and 6 cases failed.The mobility had no significant effect on the success rate(P=0.28).Pulp chamber calcification and pulp canal obli-teration were not observed in all the post-operative radiographs.Conclusion:The one year clinical and radiographic success rates obtained in this study indicate that iRoot BP Plus? is an appropriate pulp cap-ping material option for pulpotomy treatment of complicated crown fracture in immature permanent teeth without displacement injuries.This technique has broad promotional value.

Objective To investigate the predictive value of new simplified insulin resistance(IR)assessment indexes in identifying subclinical left ventricular systolic function impairment in patients with type 2 diabetes mellitus(T2DM).Methods A total of 150 T2DM patients with preserved left ventricular ejection fraction(LVEF≥50%)who were admitted to Department of Endocrinology of the First Affiliated Hospital of Air Force Medical University from June 2021 to December 2021 were retrospectively analyzed.All patients underwent two-dimensional speckle tracking echocardiography to measure left ventricular global longitudinal strain(GLS).According to GLS value,the subjects were divided into the normal group(GLS≥18%group,n=80)and the impaired group(GLS<18%group,n=70).Some new simplified IR assessment indicators were calculated and compared between the two groups,including body mass index(BMI),TG/HDL-C ratio,triglyceride-glucose(TyG)index,TyG-BMI index,TyG-WHR and metabolic score for IR(METS-IR).Correlation between the GLS and the new simplified IR assessment indexes was analyzed.The receiver operating characteristic(ROC)curve was used to analyze the diagnostic efficacy of different simplified IR assessment indexes,with the area under the curve(AUC)calculated.Furthermore,according to whether the subjects were complicated with hypertension,binary logistics regression analysis was performed to explore the independent correlation between the simplified IR assessment index and GLS<18%.Results Total 150 were included with aged(54.5±13.7)years with 96(64.0%)men and 54(36.0%)women.Compared with the GLS≥18%group,the TG/HDL-C ratio,TyG index,TyG-BMI,and METS-IR of subjects in the GLS<18%group were significantly increased(P<0.05).Pearson correlation analysis showed that TG/HDL-C ratio,TyG index,TyG-BMI,TyG-WHR,and METS-IR were negatively correlated with GLS(P<0.05).ROC analysis showed that TyG index had a certain predictive value for the evaluation of GLS<18%(AUC=0.678,95%CI 0.591-0.765,P<0.001).Stratification based on hypertension and further adjusting for confounding factors,TyG index remains significantly associated with GLS<18%(OR=3.249,95%CI 1.045-10.103,P=0.042).Conclusions The novel simplified insulin resistance evaluation indexes are closely associated with left ventricular subclinical systolic dysfunction in T2DM patients with preserved ejection fraction.TyG index is an effective index to identify left ventricular subclinical dysfunction in these populations.

Objective To investigate the infection status and changing trend of hepatitis C virus(HCV)infection in hospitalized patients in medical institutions,and provide reference for formulating HCV infection prevention and control strategies.Methods HCV infection surveillance results from cross-sectional survey data reported to China Healthcare-associated Infection(HAI)Surveillance System in 2020 were summarized and analyzed,HCV positive was serum anti-HCV positive or HCV RNA positive,survey result was compared with the survey results from 2003.Results In 2020,1 071 368 inpatients in 1 573 hospitals were surveyed,738 535 of whom underwent HCV test,4 014 patients were infected with HCV,with a detection rate of 68.93％and a HCV positive rate of 0.54％.The positive rate of HCV in male and female patients were 0.60％and 0.48％,respectively,with a statistically sig-nificant difference(x2=47.18,P＜0.001).The HCV positive rate in the 50-＜60 age group was the highest(0.76％),followed by the 40-＜50 age group(0.71％).Difference among all age groups was statistically signifi-cant(x2=696.74,P＜0.001).In 2003,91 113 inpatients were surveyed.35 145 of whom underwent HCV test,resulting in a detection rate of 38.57％;775 patients were infected with HCV,with a positive rate of 2.21％.In 2020,HCV positive rates in hospitals of different scales were 0.46％-0.63％,with the highest in hospital with bed numbers ranging 600-899.Patients'HCV positive rates in hospitals of different scales was statistically signifi-cant(X2=35.34,P＜0.001).In 2020,12 provinces/municipalities had over 10 000 patients underwent HCV-rela-ted test,and HCV positive rates ranged 0.19％-0.81％,with the highest rate from Hainan Province.HCV posi-tive rates in different departments were 0.06％-0.82％,with the lowest positive rate in the department of pedia-trics and the highest in the department of internal medicine.In 2003 and 2020,HCV positive rates in the depart-ment of infectious diseases were the highest,being 7.95％and 3.48％,respectively.Followed by departments of orthopedics(7.72％),gastroenterology(3.77％),nephrology(3.57％)and general intensive care unit(ICU,3.10％)in 2003,as well as departments of gastroenterology(1.35％),nephrology(1.18％),endocrinology(0.91％),and general intensive care unit(ICU,0.79％)in 2020.Conclusion Compared with 2003,HCV positive rate decreased significantly in 2020.HCV infected patients were mainly from the department of infectious diseases,followed by departments of gastroenterology,nephrology and general ICU.HCV infection positive rate varies with gender,age,and region.

Objective To observe the effect of multi-modal hand hygiene(HH)intervention on HH compliance,as well as the relationship between HH compliance and the healthcare-associated(HA)case infection incidence.Methods From 2014 to 2022,the infection control team in a tertiary first-class hospital implemented multi-modal HH intervention for health care workers(HCWs).The changing trend of HH monitoring data,the correlation be-tween HH compliance rate and HA case infection incidence were analyzed retrospectively.Results The consump-tion of HH products in the wards showed a stable upward trend;HH compliance rate increased from 64.98％in 2014 to 85.01％in 2022(P＜0.001),and HA case infection incidence decreased from 1.21％to 0.83％(P＜0.05).HH compliance rate was negatively correlated with HA case infection incidence(r=-0.369,P=0.027).HH compliance rates in different regions and job posts in each quarter were increased(P＜0.001).For 5 different HH moments in each quarter,HH compliance rate fluctuated slightly before sterile manipulation and after touching patient;presented rising trend after touching surroundings around patient,and decreased before touching patient and after touching patient's body fluid since 2020(P＜0.001).Conclusion Multi-modal HH intervention can im-prove the HH compliance of HCWs,improving their HH awareness is conducive to reducing HA case infection incidence.

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 To investigate the epidemiological characteristics and mutation spectrum of monogenic diseases in Chinese population through a large-scale,multicenter carrier screening.Methods This study was conducted among a total of 33 104 participants(16 610 females)from 12 clinical centers across China.Carrier status for 223 genes was analyzed using high-throughput sequencing and different PCR methods.Results The overall combined carrier frequency was 55.58%for 197 autosomal genes and 1.84%for 26 X-linked genes in these participants.Among the 16 669 families,874 at-risk couples(5.24%)were identified.Specifically,584 couples(3.50%)were at risk for autosomal genes,306(1.84%)for X-linked genes,and 16 for both autosomal and X-linked genes.The most frequently detected autosomal at-risk genes included GJB2(autosomal recessive deafness type 1A,393 couples),HBA1/HBA2(α-thalassemia,36 couples),PAH(phenylketonuria,14 couples),and SMN1(spinal muscular atrophy,14 couples).The most frequently detected X-linked at-risk genes were G6PD(G6PD deficiency,236 couples),DMD(Duchenne muscular dystrophy,23 couples),and FMR1(fragile X syndrome,17 couples).After excluding GJB2 c.109G>A,the detection rate of at-risk couples was 3.91%(651/16 669),which was lowered to 1.72%(287/16 669)after further excluding G6PD.The theoretical incidence rate of severe monogenic birth defects was approximately 4.35‰(72.5/16 669).Screening for a battery of the top 22 most frequent genes in the at-risk couples could detect over 95%of at-risk couples,while screening for the top 54 genes further increased the detection rate to over 99%.Conclusion This study reveals the carrier frequencies of 223 monogenic genetic disorders in the Chinese population and provides evidence for carrier screening strategy development and panel design tailored to the Chinese population.In carrier testing,genetic counseling for specific genes or gene variants can be challenging,and the couples need to be informed of these difficulties before testing and provided with options for not screening these genes or gene variants.

Objective·To explore the effects and possible molecular mechanisms of nanoplastics(NPs)on severe asthma.Methods·A mouse model of severe asthma was established by using house dust mite(HDM)and lipopolysaccharide(LPS)co-stimulation.Polystyrene nanoplastics(PS-NPs)were instilled into the severe asthma mice's airways.Subsequently,bronchoalveolar lavage fluid(BALF)was collected and lung tissue sections were prepared.Flow cytometry,hematoxylin-eosin(H-E)staining,periodic acid-Schiff(PAS)staining,immunohistochemistry,and terminal dexynucleotidyl transferase-mediated dUTP nick-end labeling(TUNEL)staining,were used to observe the effects of PS-NPs on airway inflammation,mucus secretion,alveolar structure,and the proliferation and apoptosis of alveolar type Ⅱ epithelial cells(AT2 cells)in severe asthma mice.The CCK-8 assay and Annexin Ⅴ/PI double staining were performed to evaluate the effects of PS-NPs on the proliferation and apoptosis of the mouse AT2 cell line MLE-12.DNA damage in AT2 cells caused by PS-NPs was detected by using anti-γ-H2A.X immunofluorescence staining.The expression of genes in the ATR/Chk1/p53 signaling pathway was detected by real-time fluorescent quantitative polymerase chain reaction(qPCR),Western blotting,Tyramide signal amplification(TSA)multiplex immunofluorescence staining,and immunofluorescence co-localization,respectively.The ATR-specific inhibitor Ceralasertib(AZD6738)was administrated to MLE-12 cells in combination with PS-NPs to evaluate the recovery effect on cell proliferation and apoptosis.Results·Flow cytometry revealed that exposure to PS-NPs increased the total number of inflammatory cells and the number of each type of inflammatory cells in the BALF of mice with severe asthma,with a predominance of neutrophils.H-E and PAS staining showed significant increase in airway inflammatory cell infiltration and mucus secretion,as well as disruption of alveolar structure.In vitro,the CCK-8 assay demonstrated significant,dose-dependent inhibition of MLE-12 cell proliferation by PS-NPs.The Annexin V/PI double staining assay indicated a higher apoptosis rate of(56.20±3.84)%in PS-NP-exposed cells compared to(23.22±2.52)%in the control group.Immunofluorescence staining demonstrated that PS-NPs were phagocytosed by MLE-12 cells and localized around the nucleus.TUNEL staining confirmed enhanced apoptosis in AT2 cells in vivo.The immunofluorescence assay revealed that compared to the control group,the expression of the DNA damage marker γ-H2A.X increased in the experimental group.qPCR,Western blotting,and TSA multiplex staining results showed that PS-NP-induced elevated expression of mRNA and proteins was related to the ATR/Chk1/p53 pathway in MLE-12 cells.Moreover,immunofluorescence co-localization also confirmed the induction of ATR and p53 proteins in AT2 cells in vivo.The ATR-specific inhibitor Ceralasertib partially restored the PS-NP-induced inhibition of cell proliferation and enhancement of apoptosis in MLE-12 cells.Conclusion·NPs exposure leads to DNA damage in AT2 cells,activating the ATR/Chk1/p53 signaling pathway and exacerbating airway inflammation and alveolar damage in mice with severe asthma.

Objective To develop an MRI-based habitat radiomics model for the preoperative prediction of endometrial cancer(EC)molecular subtypes.Methods Patients with pathologically proven EC from two hospitals were included in the training(n=270)and testing(n=70)cohorts.All patients had preoperative MRI and histological and molecular diagnoses.First,the tumor was divided into habitat subregions based on diffusion-weighted imaging(DWI)and contrast-enhanced(CE)images.Subsequently,habitat radiomic features were extracted from different subregions of T1-weighted imaging(T1WI),T2-weighted imaging(T2WI),DWI,and CE images.Three machine learning classifiers,including logistic regression,support vector machines,and random forests,were applied to develop predictive models for p53-abnormal endometrial cancer,with model performance validated.The model demonstrating the best overall predictive performance was selected as the habitat radiomics model.Using the same procedure,a whole-region radiomics model based on T1WI,T2WI,DWI,and CE sequences and a clinical model were constructed.The performance of the models was evaluated using receiver operating characteristic curves,and DeLong's test was employed to compare differences between the models.Decision curve analysis was used to assess the clinical benefits of the models'application.Results After feature selection,eight habitat radiomic features were retained to construct the habitat radiomics model,ten features for the whole-region radiomics model,and three clinical features for the clinical model.The habitat radiomics model achieved the highest area under the curve(AUC),with 0.855(0.788-0.922)in the training cohort and 0.769(0.631-0.907)in the testing cohort.DeLong's test showed that the habitat radiomics model outperformed the whole-region radiomics model in the training cohort(P=0.001),but there was no significant difference in the testing cohort(P=0.543).In both cohorts,the habitat radiomics model outperformed the clinical model(P=0.007,training cohort;P=0.038,testing cohort).Decision curve analysis(DCA)demonstrated that this model provided clinical benefit for diagnosis within a threshold probability range of approximately 0.2-0.8.Conclusion The MRI-based habitat radiomics model can accurately predict p53-abnormal EC,outperforming both the whole-region radiomics model and the clinical model,and is useful for the non-invasive molecular subtyping of endometrial cancer before surgery.