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.

Objective:To determine the status of nutritional literacy and its influencing factors among the peritoneal dialysis (PD) patients. Methods:The patients who underwent PD and long-term follow-up in the Department of Nephrology,General Hospital of Eastern Theater Command between January and October,2023 were enrolled in this study. The status of nutritional literacy in the patients was assessed through collecting and analyzing the data on the patients' general information,the current nutritional status,and laboratory-and dialysis-related indicators. Results:The average score of nutritional literacy in the enrolled patients were (24.49±3.35). Significant differences in nutritional literacy scoring were observed in the different patient subgroups according to the patients' educational background,dialysis time or times of receiving multidisciplinary diet guidance (all P values<0.05). The nutritional literacy levels of PD patients were negatively correlated to the concentrations of serum calcium and prealbumin,and left ventricular posterior wall thickness,and postively correlated to prealbumin level(P<0.05). Basing on multiple linear regression analysis,the times of receiving multidisciplinary diet guidance,educational background and serum prealbumin level were identified as independent influencing factors for the nutritional literacy levels in PD patients,respectively (all P values<0.05). Conclusions:The present study showed that the nutritional literacy of PD patients was in the middle level. In clinical practice,to enhance multidisciplinary diet guidance and management at the early stage of PD could contribute to improve the nutritional status of PD patients. In addition,to increase the patients' nutritional knowledge and health management ability might be also helpful for the nutritional levels of PD patients.

Objective To explore the automated identification and diameter measurement methods for inferior vena cava (IVC) based on clinical ultrasound images of IVC. Methods An automated identification and localization method based on topology and automatic tracking algorithm was proposed. Tracking algorithm was used for identifying and continuously locating to improve the efficiency and accuracy of measurement. Tests were conducted on 18 sets of ultrasound data collected from 18 patients in intensive care unit (ICU),with clinicians' measurements as the gold standard. Results The recognition accuracy of the automated method was 94.44％ (17/18),and the measurement error of IVC diameter was within the range of±1.96s (s was the standard deviation). The automated method could replace the manual method. Conclusion The proposed IVC automated identification and localization algorithm based on topology and automatic tracking algorithm has high recognition success rate and IVC diameter measurement accuracy. It can assist clinicians in identifying and locating IVC,so as to improve the accuracy of IVC measurement.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.

Objective To understand the changing distribution and antimicrobial resistance profiles of Klebsiella strains in 52 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Antimicrobial susceptibility testing was carried out according to the unified CHINET protocol.The susceptibility results were interpreted according to the breakpoints in the Clinical & Laboratory Standards Institute(CLSI)M100 document.Results A total of 241,549 nonduplicate Klebsiella strains were isolated from 2015 to 2021,including Klebsiella pneumoniae(88.0％),Klebsiella aerogenes(5.8％),Klebsiella oxytoca(5.7％),and other Klebsiella species(0.6％).Klebsiella strains were mainly isolated from respiratory tract(48.49±5.32)％.Internal medicine(22.79±3.28)％,surgery(17.98±3.10)％,and ICU(14.03±1.39)％were the top 3 departments where Klebsiella strains were most frequently isolated.K.pneumoniae isolates showed higher resistance rate to most antimicrobial agents compared to other Klebsiella species.Klebsiella isolates maintained low resistance rates to tigecycline and polymyxin B.ESBLs-producing K.pneumoniae and K.oxytoca strains showed higher resistance rates to all the antimicrobial agents tested compared to the corresponding ESBLs-nonproducing strains.The K.pneumoniae and carbapenem-resistant K.pneumoniae(CRKP)strains isolated from ICU patients demonstrated higher resistance rates to majority of the antimicrobial agents tested than the strains isolated from non-ICU patients.The CRKP strains isolated from adult patients had higher resistance rates to most of the antimicrobial agents tested than the corresponding CRKP strains isolated from paediatric patients.Conclusions The prevalence of carbapenem-resistant strains in Klebsiella isolates increased greatly from 2015 to 2021.However,the Klebsiella isolates remained highly susceptible to tigecycline and polymyxin B.Antimicrobial resistance surveillance should still be strengthened for Klebsiella strains.

Objective To investigate the changing distribution and antibiotic resistance profiles of clinical isolates of Staphylococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Staphylococcus according to the unified protocol of CHINET(China Antimicrobial Surveillance Network)using disk diffusion method and commercial automated systems.The CHINET antimicrobial resistance surveillance data from 2015 to 2021 were interpreted according to the 2021 CLSI breakpoints and analyzed using WHONET 5.6.Results During the period from 2015 to 2021,a total of 204,771 nonduplicate strains of Staphylococcus were isolated,including 136,731(66.8％)strains of Staphylococcus aureus and 68,040(33.2％)strains of coagulase-negative Staphylococcus(CNS).The proportions of S.aureus isolates and CNS isolates did not show significant change.S.aureus strains were mainly isolated from respiratory specimens(38.9±5.1)％,wound,pus and secretions(33.6±4.2)％,and blood(11.9±1.5)％.The CNS strains were predominantly isolated from blood(73.6±4.2)％,cerebrospinal fluid(12.1±2.5)％,and pleural effusion and ascites(8.4±2.1)％.S.aureus strains were mainly isolated from the patients in ICU(17.0±7.3)％,outpatient and emergency(11.6±1.7)％,and department of surgery(11.2±0.9)％,whereas CNS strains were primarily isolated from the patients in ICU(32.2±9.7)％,outpatient and emergency(12.8±4.7)％,and department of internal medicine(11.2±1.9)％.The prevalence of methicillin-resistant strains was 32.9％in S.aureus(MRSA)and 74.1％in CNS(MRCNS).Over the 7-year period,the prevalence of MRSA decreased from 42.1％to 29.2％,and the prevalence of MRCNS decreased from 82.1％to 68.2％.MRSA showed higher resistance rates to all the antimicrobial agents tested except trimethoprim-sulfamethoxazole than methicillin-susceptible S.aureus(MSSA).Over the 7-year period,MRSA strains showed decreasing resistance rates to gentamicin,rifampicin,and levofloxacin,MRCNS showed decreasing resistance rates to gentamicin,erythromycin,rifampicin,and trimethoprim-sulfamethoxazole,but increasing resistance rate to levofloxacin.No vancomycin-resistant strains were detected.The prevalence of linezolid-resistant MRCNS increased from 0.2％to 2.3％over the 7-year period.Conclusions Staphylococcus remains the major pathogen among gram-positive bacteria.MRSA and MRCNS were still the principal antibiotic-resistant gram-positive bacteria.No S.aureus isolates were found resistant to vancomycin or linezolid,but linezolid-resistant strains have been detected in MRCNS isolates,which is an issue of concern.

Objective To predict the structure and antigenic epitope of the Strongyloides stercoralis serine protease inhibitor 1 (Ss-SRPN-1) protein using bioinformatics tools, and to construct prokaryotic expression plasmids for expression of recombinant Ss-SRPN-1 protein, so as to provide the basis for unraveling the function of the Ss-SRPN-1 protein. Methods The amino acid sequence of the Ss-SRPN-1 protein was downloaded from the NCBI database, and the physicochemical properties, structure and antigenic epitopes of the Ss-SRPN-1 protein were predicted using bioinformatics tools, including ExPASy, SWISS-MODEL and Protean. Primers were designed according to the nucleotide sequences of Ss-SRPN-1, and the Ss-SRPN-1 gene was amplified, cloned and sequenced with genomic DNA extracted from the infective third-stage larvae of S. stercoralis as a template. The Ss-SRPN-1 protein sequence was cloned into the pET28a (+) expression vector and transformed into Escherichia coli BL21 (DE) cells for induction of the recombinant Ss-SRPN-1 protein expression. The recombinant Ss-SRPN-1 protein was then purified and identified using Western blotting and mass spectrometry. Results Bioinformatics analysis showed that the Ss-SRPN-1 protein, which was composed of 372 amino acids and had a molecular formula of C₁₉₄₈H₃₀₄₆N₄₈₈O₅₇₅S₁₆, was a stable hydrophilic protein, and the subcellular localization of the protein was predicted to be extracellular. The Ss-SRPN-1 protein was predicted to contain 11 dominant B-cell antigenic epitopes and 20 T-cell antigenic epitopes. The Ss-SRPN-1 gene with a length of 1 119 bp was successfully amplified, and the recombinant plasmid pET28a (+)/Ss-SRPN-1 was constructed and transformed into E. coli BL21(DE) cells. The expressed recombinant Ss-SRPN-1 protein had a molecular weight of approximately 43 kDa, and was characterized as a Ss-SRPN-1 protein. Conclusions The recombinant Ss-SRPN-1 protein has been expressed successfully, and this recombinant protein may be a potential vaccine candidate against strongyloidiasis.

BACKGROUND: Core muscle functional strength training (CMFST) has been reported to reduce injuries to the lower extremity. However, no study has confirmed whether CMFST can reduce the risk of low back pain (LBP). OBJECTIVE: This study identified the effects of CMFST on the incidence of LBP in military recruits. DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: We performed a prospective, open-label, randomized, controlled study in a population of young healthy male naval recruits from a Chinese basic combat training program. Participants were randomly assigned to either the core group or the control group. In additional to normal basic combat training, recruits in the core group underwent a CMFST program for 12 weeks, while recruits in the control group received no extra training. MAIN OUTCOME MEASURES: At the beginning of the study and at the 12th week, the number of participants with LBP was counted, and lumbar muscle endurance was measured. In addition, when participants complained of LBP, they were assessed using the visual analog scale (VAS) and Roland Morris Disability Questionnaire (RMDQ). RESULTS: A total of 588 participants were included in the final analysis (295 in the core group and 293 in the control group). The incidence of LBP in the control group was about twice that of the core group over the 12-week study (20.8% vs 10.8%, odds ratio: 2.161-2.159, P < 0.001). The core group had better lumbar muscle endurance at 12 weeks than the control group ([200.80 ± 92.98] s vs [147.00 ± 84.51] s, P < 0.01). There was no significant difference in VAS score between groups, but the core group had a significantly lower RMDQ score at week 12 than the control group (3.33 ± 0.58 vs 5.47 ± 4.41, P < 0.05). CONCLUSION This study demonstrated that the CMFST effectively reduced the incidence of LBP, improved lumbar muscle endurance, and relieved the dysfunction of LBP during basic military training.
Humans ; Low Back Pain/prevention & control* ; Male ; Military Personnel ; Muscles ; Prospective Studies ; Resistance Training ; Treatment Outcome