The incidence of dementia increased significantly in the context of an aging population,imposing a significant burden on the economy and society.Therefore,finding the specific mechanism underlying cognitive decline in aging is of paramount significance.Recently,the role of microglia in the initiation and progression of cognitive decline in aging has become a research hotspot.Microglia,the resident immune cells of CNS,play important roles in immunosurveillance,synaptic pruning,damage repair and maintaining immune homeostasis.However,microglia undergo a variety of changes in cell morphology,gene expression and functional status with aging.This article review the impact of normal aging on microglia and the role of microglia in the pathogenesis of cognitive decline in aging,to provide a novel strategy for slowing or preventing the onset of dementia.

Metastasis-associated lung adenocarcinoma transcript 1 ( MALAT1) is a well-established oncogenic long non-coding RNA, the higher expression of which is strongly correlated with cancer events such as tumorigenesis, progression, metastasis, drug resistance, and treatment outcome in solid cancers. Recently, a series of studies has highlighted its potential role in hematological malignancies in terms of these events. Similar to solid cancers, MALAT1 can regulate various target genes via sponging and epigenetic mechanisms, but the miRNAs sponged by MALAT1 differ from those identified in solid cancers. In this review, we systematically describe the role and underlying mechanisms of MALAT1 in multiple types of hematological malignancies, including regulation of cell proliferation, metastasis, stress response, and glycolysis. Clinically, MALAT1 expression is related to poor treatment outcome and drug resistance, therefore exhibiting potential prognostic value in multiple myeloma, lymphoma, and leukemia. Finally, we discuss the evaluation of MALAT1 as a novel therapeutic target against cancer in preclinical studies.

Amino acid surfactants (AAS) have excellent properties such as low toxicity,antibacterial,mildness,and corrosion resistance. In recent years,they have been widely applied in the field of daily chemicals,food and pharmaceutical industry. It is pointed out that the structure at molecular level largely affects the physical and chemical properties of AAS materials. In this work,the structures of solid-state N-lauroyl-L-alanine (NLLA) including intermolecular interactions,molecular local dynamics and molecular assembly were investigated by a variety of solid-state nuclear magnetic resonance (SSNMR) techniques. Based on 2D 1H-1H double quantum-single quantum (2D 1H-1H DQ-SQ),1H-1H DQ sideband pattern and molecular simulation,it was found that there was a stable intermolecular hydrogen bond formed between the carboxyl units of two NLLA molecules. Combined with the study of 2D frequency switched Lee—Goldberg heteronuclear correlation (2D 13C-1H FSLG-HETCOR) and 13C T1,another type of hydrogen bond was probed,which existed between amide units of neighboring molecules. In addition,the conformation of alkyl chain ends was investigated. According to 1D 13C{1H}cross polarization/magic angle spinning (CP/MAS) and 2D 13C-1H FSLG-HETCOR spectra,it was revealed that the alkyl-chain ends had both gauche and trans conformations. Moreover,the trans conformation showed two distinct 13C chemical shifts,originated from two NLLA molecular assembly forms. Accordingly,two NLLA molecular assembly structures were suggested which were transoid form and cisoid form. This work provided a SSNMR investigation strategy for characterizing the molecular local structure and dynamics of AAS materials,which helped task of researching and developing materials with improved chemical and physical properties.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective:To study the serological characteristics of ABO*A2.08 subtype and explore its genetic molecular mechanism.Methods:ABO blood group identification was performed on proband and her family members by routine serological methods.ABO genotyping and sequence analysis were performed by polymerase chain reaction-sequence specific primer(PCR-SSP),and direct sequencing of PCR products from exons 6 and 7 of ABO gene were directly sequenced and analyzed.The effect of gene mutation in A2.08 subtype on structural stability of GTA protein was investigated by homologous protein conserved analysis,3D molecular modeling and protein stability prediction.Results:The proband's serological test results showed subtype Ax,and ABO genotyping confirmed that the proband's genotype was ABO*A207/08.Gene sequencing of the proband's father confirmed the characteristic variation of c.539G＞C in the 7th exon of ABO gene,leading to the replacement of polypeptide chain p.Arg180Pro(R180P).3D protein molecular modeling and analysis suggested that the number of hydrogen bonds of local amino acids in the protein structure was changed after the mutation,and protein stability prediction showed that the mutation had a great influence on the protein structure stability.Conclusion:The mutation of the 7th exon c.539G＞C of ABO gene leads to the substitution of polypeptide chain amino acid,which affects the structural stability of GTA protein and leads to the change of enzyme activity,resulting in the A2.08 phenotype.The mutated gene can be stably inherited.

Aim To design the pyrimidoindole deriva-tive N-butyl-9H-pyrimido[4,5-b]indole-2-carboxamide(BFPI)and synthesize it to investigate whether it in-hibits macrophage pyroptosis and foaming effects through the NLRP3/Caspase-1 pathway.Methods BFPI was synthesized using 2,4,6-triethoxycarbonyl-l,3,5-triazine and 2-aminoindole as starting materials and structurally characterized by 1H NMR,13C NMR,and ESI-MS.The in vitro cultured mouse monocyte macro-phage cell line RAW264.7 was divided into blank,model(PA)and therapeutic(BFPI)groups,and the cells in each group were treated with the corresponding culture medium for 24 h.The proliferative viability was detected by MTT assay,and the formation of intracel-lular lipid droplets was detected by oil red O staining,and NLRP3 was detected by Western-blot and RT-qPCR,caspase-1 and MCP-1 mRNA and protein ex-pression levels by Western blot and RT-qPCR.Results Compared with the blank group,the proliferation vi-ability of cells in the model group significantly de-creased and the formation of lipid droplets significantly increased;compared with the model group,the prolif-eration viability of cells in the treatment group signifi-cantly increased and the formation of lipid droplets sig-nificantly decreased,and the differences were statisti-cally significant(P＜0.01);compared with the blank group,the cellular NLRP3,caspase-1 and MCP-1 mR-NA and protein expression levels of cells in the model group significantly increased;compared with the model group,the expression levels of the above indexes of the cells in the treatment group significantly decreased,and the difference was statistically significant(P＜0.01).Conclusions BFPI contributes to delaying macrophage-derived foam cell formation during athero-genesis by inhibiting macrophage NLRP3,caspase-1,and MCP-1 expression and thereby promoting their pro-liferation and inhibiting lipid phagocytosis.

Aim To explore the improvement effect of Bazi Bushen capsule on thymic degeneration in SAMP6 mice and the possible mechanism.Methods Twenty 12 week old male SAMP6 mice were randomly divided into the model group(SAMP6)and the Bazi Busheng capsule treatment group(SAMP6+BZBS).Ten SAMR1 mice were assigned to a homologous control group(SAMR1).The SAMP6+BZBS group was oral-ly administered Bazi Bushen capsule suspension(2.8 g·kg-1)daily,while the other two groups were orally administered an equal amount of distilled water.After nine weeks of administration,the morphology of the thymus in each group was observed and the thymus in-dex was calculated;HE staining was used to observe the structural changes of thymus tissue;SA-β-gal stai-ning was used to detect thymic aging;flow cytometry was used to detect the proportion of thymic CD3+T cells in each group;Western blot was used to detect the levels of p16,Bax,Bcl-2,and cleaved caspase-3 proteins in thymus;immunofluorescence was applied to detect the proportion of cortical thymic epithelial cells in each group;ELISA was employed to detect IL-7 lev-els in thymus.Results Compared with the SAMP6 group,the thymic index of the SAMP6+BZBS group significantly increased(P＜0.05);the disordered thy-mic structure was significantly improved;the positive proportion of SA-β-gal staining significantly decreased(P＜0.01);the proportion of CD3+T cells apparently increased(P＜0.05);the level of p16 protein signifi-cantly decreased(P＜0.05);the level of Bcl-2 pro-tein significantly increased(P＜0.05),while the lev-el of cleaved caspase-3 protein markedly decreased(P＜0.05);the proportion of cortical thymic epithelial cells evidently increased;the level of IL-7 significantly increased(P＜0.01).Conclusions Bazi Bushen capsule can delay thymic degeneration,inhibit cell ap-optosis in thymus and promote thymic cell development in SAMP6 mice,which may be related to increasing the proportion of cortical thymic epithelial cells and promoting IL-7 secretion.

Aim To investigate the effects of berberine(BBR)combined with 5'-n-ethylformamidoadenosine(NECA)on myocardial H9c2 and HL-1 cell damage induced by hypoxia/reoxygenation(H/R).Methods H9c2 and HL-1 cells were divided into the Control group,BBR group,NECA group,combined administra-tion group,H/R group,BBR+H/R group,NECA+H/R group,and combined administration+H/R group.CCK-8 was used to detect cell viability in each group.The TMRE kit was used to detect MMP.DCFH-DA was used to detect ROS content.The Mito SOX Red fluorescent probe was used to detect mitochondrial su-peroxide.The expressions of COX Ⅳ,Tom20,and Tim23 were detected by Western blot.The expression of COX Ⅳ and Tom20 genes was detected by qRT-PCR.Results In H9c2 cells,the cell viability and TMRE fluorescence intensity in the H/R group were significantly decreased compared with the Control group.The protein expressions of COX Ⅳ,Tom20,and Tim23,gene expressions of COX Ⅳ and Tom20,ROS,and mitochondrial superoxide contents were significant-ly increased.Compared with the H/R group,the cell viability of BBR and NECA were enhanced after ad-ministration alone.The contents of ROS and mitochon-drial superoxide were significantly decreased.In HL-1 cells,cell viability in the H/R group was significantly decreased compared with the Control group.The con-tents of ROS and mitochondrial superoxide were signifi-cantly increased.Compared with the H/R group,BBR and NECA alone and combined administration en-hanced cell viability.The contents of ROS and mito-chondrial superoxide were significantly decreased.Conclusion The administration of BBR and NECA a-lone or in combination can reduce the production of mi-tochondrial superoxide and cell ROS,thereby allevia-ting mitochondrial damage,alleviating oxidative stress damage,and ultimately reducing H/R-induced myocar-dial cell damage.

Objective: To analyze the drug resistance and multilocus sequence typing of five types of diarrheagenic Escherichia coli (DEC) isolated from diarrhea outpatients of diarrhea comprehensive monitoring designated hospital in Qingpu District, Shanghai from 2015 to 2019. Methods: From January 2015 to December 2019, five types of DEC, isolated and identified from diarrhea outpatient cases' anal swabs of the Qingpu branch of Zhongshan Hospital were collected to determine the minimal inhibitory concentration by using the micro broth dilution susceptibility test. The strains, resistant to the third-generation cephalosporins or carbapenems, or producing ESBLs, were selected based on the results of sensitivity tests and determined by WGS. The MLST typing of DEC was analyzed based on the WGS technology and the minimum spanning tree was constructed by BioNumerics 7.6 software to analyze the local dominant flora. Results: A total of 513 strains of DEC were detected and isolated from 4 494 anal swabs, with a detection rate of 11.42%. About 500 strains were tested for drug sensitivity to nine antibiotics in four classes, including 330 strains of enterotoxigenic E.coli (ETEC), 72 strains of enteroaggregative E.coli (EAEC), 95 strains of enteropathogenic E.coli (EPEC), 1 strain of enterohemorrhagic E.coli (EHEC), and 2 strains of enteroinvasive E.coli (EIEC). From 2015 to 2019, the resistance rate of cefotaxime-clavulanic acid was significantly different (P<0.05). The resistance rate of virulence types of DEC to nalixic acid was significantly different (P<0.05). About 71 strains of DEC were determined by WGS, and 77 drug-resistant genes were detected. Strains were classified into 32 ST subtypes, with the dominant genotypes being ST-1491 (29.6%, 21/71) and ST-10 Complex (23.9%, 17/71). All ST-1491 produced ESBLs, which were bla_CTX-M gene mutant strains. The dominant type of ST-10 complex was ST-218 (35.3%, 6/17). In addition, 8 strains of EAEC, 14 strains of EPEC and 49 strains of ETEC were classified into 7, 14 and 18 ST subtypes, respectively. Conclusion: The drug resistance of DEC strains from the diarrhea outpatient case of Qingpu District is serious. The ST types of EAEC and EPEC are highly polymorphic. The dominant ST types of DEC are basically consistent with the common genotypes in southeast China.

Objective: To identify the risk factors in mortality of pediatric acute respiratory distress syndrome (PARDS) in pediatric intensive care unit (PICU). Methods: Second analysis of the data collected in the "efficacy of pulmonary surfactant (PS) in the treatment of children with moderate to severe PARDS" program. Retrospective case summary of the risk factors of mortality of children with moderate to severe PARDS who admitted in 14 participating tertiary PICU between December 2016 to December 2021. Differences in general condition, underlying diseases, oxygenation index, and mechanical ventilation were compared after the group was divided by survival at PICU discharge. When comparing between groups, the Mann-Whitney U test was used for measurement data, and the chi-square test was used for counting data. Receiver Operating Characteristic (ROC) curves were used to assess the accuracy of oxygen index (OI) in predicting mortality. Multivariate Logistic regression analysis was used to identify the risk factors for mortality. Results: Among 101 children with moderate to severe PARDS, 63 (62.4%) were males, 38 (37.6%) were females, aged (12±8) months. There were 23 cases in the non-survival group and 78 cases in the survival group. The combined rates of underlying diseases (52.2% (12/23) vs. 29.5% (23/78), χ²=4.04, P=0.045) and immune deficiency (30.4% (7/23) vs. 11.5% (9/78), χ²=4.76, P=0.029) in non-survival patients were significantly higher than those in survival patients, while the use of pulmonary surfactant (PS) was significantly lower (8.7% (2/23) vs. 41.0% (32/78), χ²=8.31, P=0.004). No significant differences existed in age, sex, pediatric critical illness score, etiology of PARDS, mechanical ventilation mode and fluid balance within 72 h (all P>0.05). OI on the first day (11.9(8.3, 17.1) vs.15.5(11.7, 23.0)), the second day (10.1(7.6, 16.6) vs.14.8(9.3, 26.2)) and the third day (9.2(6.6, 16.6) vs. 16.7(11.2, 31.4)) after PARDS identified were all higher in non-survival group compared to survival group (Z=-2.70, -2.52, -3.79 respectively, all P<0.05), and the improvement of OI in non-survival group was worse (0.03(-0.32, 0.31) vs. 0.32(-0.02, 0.56), Z=-2.49, P=0.013). ROC curve analysis showed that the OI on the thind day was more appropriate in predicting in-hospital mortality (area under the curve= 0.76, standard error 0.05,95%CI 0.65-0.87,P<0.001). When OI was set at 11.1, the sensitivity was 78.3% (95%CI 58.1%-90.3%), and the specificity was 60.3% (95%CI 49.2%-70.4%). Multivariate Logistic regression analysis showed that after adjusting for age, sex, pediatric critical illness score and fluid load within 72 h, no use of PS (OR=11.26, 95%CI 2.19-57.95, P=0.004), OI value on the third day (OR=7.93, 95%CI 1.51-41.69, P=0.014), and companied with immunodeficiency (OR=4.72, 95%CI 1.17-19.02, P=0.029) were independent risk factors for mortality in children with PARDS. Conclusions: The mortality of patients with moderate to severe PARDS is high, and immunodeficiency, no use of PS and OI on the third day after PARDS identified are the independent risk factors related to mortality. The OI on the third day after PARDS identified could be used to predict mortality.
Female ; Male ; Humans ; Child, Preschool ; Infant ; Child ; Critical Illness ; Pulmonary Surfactants/therapeutic use* ; Retrospective Studies ; Risk Factors ; Respiratory Distress Syndrome/therapy*