Neurological disorders, including Alzheimer’s disease (AD), Parkinson’s disease (PD), cerebral ischemia, and multiple sclerosis (MS), impose an escalating global health burden and remain largely incurable. These disorders arise from multifactorial and interconnected pathological processes, such as chronic neuroinflammation, oxidative stress, protein misfolding and aggregation, demyelination, and neurovascular dysfunction. Despite substantial advances in elucidating disease-associated molecular mechanisms, current therapeutic strategies are predominantly symptomatic and fail to effectively halt or reverse disease progression. This limitation highlights the urgent need to identify endogenous regulatory molecules capable of coordinating neuronal survival, synaptic maintenance, inflammatory control, and tissue repair within the central nervous system (CNS). Pleiotrophin (PTN) is a heparin-binding, growth-associated cytokine that has emerged as a key regulator of neural development, plasticity, and regeneration. Structurally, PTN contains multiple high-affinity heparin-binding domains that facilitate interactions with extracellular matrix components and cell surface proteoglycans, enabling spatially restricted and context-dependent signaling. Through these molecular properties, PTN functions as a multifunctional organizer of neural growth, plasticity, and tissue remodeling across developmental and adult stages. Its diverse biological effects are executed through a multi-receptor signaling system that integrates extracellular cues with intracellular programs governing cellular survival, migration, and differentiation. Notably, PTN displays a highly dynamic and cell type-specific expression pattern in the central nervous system, being enriched in neural progenitor cells during development and later restricted to discrete neuronal populations, neural stem cells, and non-neuronal niche cells—including astrocytes, pericytes, and vascular endothelial cells—which serve as critical sources of PTN under physiological and pathological conditions. PTN expression is tightly regulated during development and exhibits pronounced plasticity in response to pathological stimuli. Under physiological conditions, PTN is transiently expressed during critical windows of neural growth and synaptogenesis, supporting neuron-glia interactions and myelin formation. In contrast, in pathological contexts such as amyloid β-protein (Aβ) accumulation in AD, dopaminergic neuron degeneration in PD, demyelination in MS, and ischemic brain injury, PTN expression is frequently dysregulated, suggesting an active role in disease-associated remodeling rather than a passive bystander effect. Importantly, accumulating evidence indicates that PTN exerts a dual and context-dependent influence on neurological disorders. On the one hand, aberrant PTN signaling may contribute to maladaptive responses, including sustained glial activation, dysregulated neuroinflammation, extracellular matrix remodeling, and enhanced Aβ deposition. On the other hand, PTN displays robust neuroprotective and reparative functions by promoting neuronal survival, enhancing oligodendrocyte maturation and remyelination, and stimulating post-injury angiogenesis, thereby facilitating tissue repair and functional recovery. At the mechanistic level, PTN signaling is characterized by extensive cross-talk among receptor-dependent pathways. Activation of anaplastic lymphoma kinase (ALK) triggers canonical PI3K-AKT-mTOR and MAPK cascades that support neuronal survival and axonal integrity. PTN binding to protein tyrosine phosphatase receptor type Z1 (PTPRZ1) induces conformational inhibition of its phosphatase activity, resulting in increased phosphorylation of downstream effectors such as β-catenin, Fyn, and Src, which regulate neuronal migration and synaptic stabilization. Syndecan-3 (SDC3) functions as both a co-receptor and an independent signaling mediator by capturing extracellular PTN, amplifying ALK- and PTPRZ1-dependent signaling, and directly modulating cytoskeletal dynamics through PKC and ERK pathways. In parallel, PTN interaction with αVβ3 integrin contributes to remodeling of the neurovascular niche, linking angiogenesis with neurogenesis and neural repair. From a translational perspective, therapeutic strategies targeting PTN can be broadly classified into 3 categories: direct enhancement of PTN signaling through exogenous protein supplementation or gene therapy-mediated upregulation, pharmacological modulation of PTN-associated receptor pathways and downstream signaling nodes, and exploitation of PTN as a dynamic biomarker to inform disease stratification and therapeutic responsiveness. These complementary approaches underscore the growing interest in PTN-centered interventions across a spectrum of neurological disorders. In summary, PTN functions not merely as a classical trophic factor but as a central signaling hub integrating inflammatory regulation, neural regeneration, and vascular remodeling within the CNS. This review aims to synthesize current insights into PTN’s molecular architecture, multi-receptor signaling mechanisms, and disease-specific functions, and to highlight emerging therapeutic strategies targeting PTN. By conceptualizing PTN as a dynamic modulator of neuronal resilience rather than a static biomarker, we propose that precise modulation of PTN signaling may offer promising avenues for therapeutic development in neurodegenerative and neuroinflammatory diseases.

ObjectiveTo compare the histological staining performance of four various tissue fixatives, including a self-developed fixative, for preparing paraffin sections of rat eyeball tissue. MethodsTwenty 5-week-old male Sprague-Dawley (SD) rats were randomly divided into 4 groups (n=5 per group). After anesthesia by intraperitoneal injection of Zoletil™ 50 at a dose of 45 mg/kg body weight, the rats were euthanized by exsanguination via the abdominal aorta. Bilateral eyeballs were carefully extracted intact and fixed for 72 h in 10% formaldehyde fixative, glutaraldehyde-formaldehyde mixed fixative, Davidson's fixative, and self-developed fixative, respectively. After fixation, the eyeballs were longitudinally sectioned along the optic nerve, with the portions containing the optic nerve preserved. The tissues were then dehydrated, embedded, and sectioned. Following hematoxylin and eosin (HE) staining, histological staining quality was compared among ocular structures including the cornea, lens, and retina. ResultsThe overall appearance of rat eyeballs showed marked shrinkage in the 10% formaldehyde group and the glutaraldehyde-formaldehyde group, whereas the eye morphology remained round and intact in the modified Davidson's fixative group and self-developed fixative group. The corneal stroma exhibited obvious rupture, and the cells were arranged in folded arrangement in the modified Davidson's fixative group, 10% formaldehyde group, and self-developed fixative group. In contrast, the corneal cells in the glutaraldehyde-formaldehyde group were neatly arranged, showing no rupture or folding, and exhibited clear staining, indicating the highest quality of corneal sectioning among all groups. In the 10% formaldehyde group, cracks were observed in the equatorial and cortical regions of the lens, but the lens fiber structure remained intact. The lenses in the modified Davidson's fixative group showed extensive rupture and detachment. The glutaraldehyde-formaldehyde group displayed only slight cracks at the equator. In the self-developed fixative group, mild red folding was limited to the peripheral lens region, with the remaining structures intact and unbroken. These findings indicated that the glutaraldehyde-formaldehyde and self-developed fixative groups achieved the best lens sectioning quality. The retina was severely detached from the choroid/sclera layer, with extensive rupture of each cellular layer in the 10% formaldehyde fixative group. In the glutaraldehyde-formaldehyde group, partial detachment between the retina and choroid/sclera was observed. The outer plexiform layer and nerve fiber layer showed separation with edema, while the cells in all layers were neatly arranged. In both the Davidson's fixative and the self-developed fixative groups, the retina remained intact without rupture, and no structural separation was observed in any layer. Both demonstrated advantages in preserving the integrity and orderly arrangement of all retinal layers; however, the self-developed fixative group exhibited greater contrast. ConclusionThe choice of fixative significantly affects the morphological preservation of various structures in the rat eye. The self-developed fixative demonstrates the best overall performance in maintaining overall eye morphology, the structural integrity of the lens, and retinal adhesion. For studies focusing solely on the corneal structure, the glutaraldehyde-formaldehyde mixed fixative is recommended. The 10% formaldehyde fixative exhibits unsatisfactory fixation effects for all the aforementioned ocular structures and is not recommended for detailed morphological studies of eyeball tissues.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To explore the predictive value of growth differentiation factor 15(GDF-15)for atrial fibrillation(AF)in patients with coronary heart disease(CHD).Methods A prospective observation cohort of 1261 elderly CHD patients was randomly sampled from the First Medical Center of Chinese PLA General Hospital from January 2012 to December 2015.ELISA was used to detect GDF-15 level in all the subjects,and their baseline data were collected.Until March 2023,93 patients were lost during the follow-up period,and finally 1168 patients completed the follow-up,with a median time of 9.4 years.According to AF occurred or not during the period,the eligible patients were divided into an AF group(197 cases)and a non-AF group(971 cases),and based on their medical history,also assigned into a stable angina pectoris(SAP,n=304)and an acute coronary syndrome group(ACS,n=864).Logistic regression analysis was used to determine whether GDF-15 is a risk factor for AF in elderly CHD patients.ROC curve was plotted to assess the predictive value of GDF-15,guideline recommended CHARGE-AF scoring model,and their combination for AF events in the patients.Results The AF group had significantly advanced age,larger proportions of smoking history,type 2 diabetes,hypertension,old myocardial infarction,stroke,ACS and administration of statins,higher ratio of angiotensin converting enzyme inhibi-tor/angiotensin receptor blocker,and elevated levels of GDF-15 and N-terminal pro-B-type natri-uretic peptide,and lower left ventricular ejection fraction,SAP incidence,and low-density lipopro-tein cholesterol,total cholesterol and triglycerides levels when compared with the non-AF group(P＜0.05,P＜0.01).Multivariate logistic regression analysis showed that GDF-15 was not a risk factor for AF in elderly CHD patients(OR=0.92,95％CI:0.74-1.16,P=0.489),but was a risk factor for AF in SAP patients(OR=1.38,95％CI:1.07-2.79,P=0.015),and in ACS patients,still not a risk factor for AF(OR=0.81,95％CI:0.63-1.05,P=0.814).ROC curve analysis showed that the AUC value of GDF-15 combined with the CHARGE-AF scoring model in predic-ting AF was 0.682 in the elderly CHD patients,0.746 in the SAP patients,and 0.680 in the ACS patients.Conclusion Elevated GDF-15 level is an independent risk factor and predictor of AF in elderly SAP patients.In SAP patients,the combination of GDF-15 and CHARGE-AF scoring model further improves the predictive performance of AF occurrence.

Objective:To investigate the nutritional risk status of children in PICU and analyze its influencing factors.Methods:From July 2021 to February 2023,all children aged 1 to 18 years admitted to PICU of Beijing Children's Hospital were investigated by using the pediatric Yorkhill Malnutrition Scoring tool(PYMS)and the clinical data questionnaire.Results:A total of 492 children in PICU were enrolled.The first nutritional risk screening results showed that there were 32 cases of no/low nutritional risk(6.5%),76 cases of medium risk(15.4%),and 384 cases of high risk(78.1%).The incidence of medium/high nutritional risk was as high as 93.5%.The PYMS score of nutritional risk in PICU was(2.61±1.42).The results of multiple linear regression analysis showed that weight,fever time before admission,white blood cells,body mass index,primary diagnosis,father's education,and diet before illness were the main influencing factors of nutritional risk of children in PICU(P<0.05).Conclusion:Children in PICU are in a state of high nutritional risk.It is suggested that children in PICU should carry out nutritional screening in a standardized manner,identify children with high nutritional risk and its influencing factors early.To actively conduct nutritional assessment and nutritional intervention could improve the clinical outcome of children in PICU.

Hepatocellular carcinoma(HCC)is a common malignant tumor worldwide,and its incidence and mortality are among the highest for many years.Due to its insidious onset,most patients are already at advanced stages when diagnosed.Improving the prognosis and survival rate of patients through conversion therapy has become a research focus lately.In recent years,with the continuous progress of biotechnology and drug development,new therapies represented by targeted and immunotherapy drugs have been widely used in HCC conversion therapy.Compared with other conversion therapy regimens,these drugs can effectively prolong the progression free survival and overall survival of patients and have advantages such as controllable adverse reactions.In addition,the combination of targeted drugs and immunotherapy drugs also plays a positive role in improving the survival benefit of HCC patients.This article aims to review the latest research progress of targeted therapy and immunotherapy in the first-and second-line treatments of HCC,and to discuss their safety and future development.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

The phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/Akt/mTOR)signaling pathway plays a crucial role in the regulation of renal fibrosis by participating in inflammatory response,oxidative stress and autophagy.Paeoniflorin exhibits remarkable efficacy in treating myocardial and liver fibrosis.This article provides a comprehensive review on the research progress of paeoniflora in preventing and treating renal fibrosis through modulation of the PI3K/Akt/mTOR signaling pathway,offering novel insights for traditional Chinese medicine-based approaches to prevent and treat renal fibrosis.

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.