Objective: To explore the value of metagenomic next-generation sequencing (mNGS) in the etiology diagnosis of bacterial meningitis in children. Methods: The etiological results of 189 children diagnosed with "bacterial meningitis" or "purulent meningitis" or "central nervous system infection" in the Children's Hospital of Fudan University from 1st January 2019 to 31st December 2020 were analyzed retrospectively. The cerebrospinal fluid (CFS) of the children with bacterial meningitis was detected by culture and mNGS respectively, and the difference of pathogen detection rate between the 2 methods was analyzed. According to the age at the time of visit, the children were divided into neonatal group (≤28 days of age) and non-neonatal group (>28 days of age), and χ2 test was used to compare the positive rate between the 2 groups. Taking CFS culture as the gold standard, the sensitivity and specificity of mNGS in the diagnosing of bacterial meningitis in children were analyzed. Results: Among these 189 children with bacterial meningitis, 116 were males and 73 were females. A total of 76 strains of pathogens were detected in blood and (or) CSF cultures, of which 50 strains (65.8%) were Gram-positive bacteria; among those, 18 strains (23.7%) of Streptococcus agalactiae, 17 strains (19.7%) of Escherichia coli and 15 strains (19.7%) of Streptococcus pneumoniae were detected with higher detection rate. The infection rate of Gram-positive bacteria in the non-neonatal group was higher than that in the neonatal group (76.0% (38/50) vs. 50.0% (13/26), χ2=5.24, P=0.020).The same CSF samples of 48 cases were tested by mNGS and culture at the same time, and the detection rate of mNGS was higher than that of CSF culture (20 cases (41.7%) vs. 12 cases (25.0%), χ2=16.45, P<0.001). The consistency of mNGS and culture results was 79.2% (38/48), and the same pathogen was detected in 11 children with both positive mNGS and CSF culture. Taking the results of CSF culture as the gold standard, the sensitivity of mNGS in the diagnosing of bacterial meningitis was 91.7%, and the specificity was 75.0%. Conclusions: The mNGS technology can improve the pathogen detection rate of bacterial meningitis in children, and has a high consistency with CSF culture. In suspected cases where the pathogen cannot be identified by traditional methods, CSF mNGS should be considered timely.

Objective: To explore the etiologies and clinical characteristics of fever of unknown origin (FUO) and to provide clues for early diagnosis of FUO. Methods: The data about etiology, age, sex, clinical course, length of hospital stays and the expression levels of inflammatory factors in fever phase of 357 pediatric inpatients who were diagnosed with FUO in Children's Hospital of Fudan University from 1 January 2016 to 31 December 2020 were collected and retrospectively analyzed. Participants were grouped into infectious disease, inflammatory disease, malignancy and others and according to the classification of diseases and also grouped into those aged<1 year, 1-<3 years,3-<6 years, 6-<12 years and 12-<18 years. Comparisons between groups were performed using the Mann-Whitney U test, Kruskal-Wallis H test and χ² test. Results: Among the 357 patients (217 males and 140 females). The age of onset was 3.9 (1.3, 9.2) years and visiting age was 5.1 (2.0, 9.3) years. The time-consuming of diagnosis was 94 (66, 213) days. The hospital stay was 8 (6, 14) days. The most frequently identified cause of FUO was infectious diseases (163 cases, 45.7%), followed by non-infectious inflammatory diseases (133 cases, 37.2%), malignancy (21 cases, 5.9%) and others (40 cases, 11.2%). The patients at younger age were more likely to be attacked by malignancy, oncologic diagnoses, and others, nevertheless patients at older age were more likely to be attacked by non-infectious inflammatory diseases oppositely (9.8 (3.6, 11.5) vs. 3.0 (1.2, 7.0), 2.3 (1.0, 5.2), 0.9 (0.5, 1.8) years, U=41.30, 15.94, 37.08, all P<0.01);106 (65%) patients were male, and 57 (35%) patients were female. This result indicated that boys were more susceptible to infectious diseases (χ²=14.73, P<0.01). Analysis of inflammatory factors in serum among 103 patients, interleukin (IL)-6 level in 40 infectious diseases patients (9 (2, 38) ng/L) was significantly lower than those of 6 tumor patients (89 (64, 599) ng/L) and 57 non-infectious inflammatory diseases patients (25 (8, 78) ng/L, U=51.05, 15.70, both P<0.05), no significant difference was observed in IL-2, IL-4, IL-10, tumor necrosis factor α and interferon among the groups (all P>0.05). The patients grouped into those aged 1-<3 years and 3-<6 years were more likely to be attacked by infectious diseases (51.3% (59/115) and 57.1% (40/70)), while patients grouped into those aged 6-<12 years and 12-<18 years were more likely to be attacked by non-infectious inflammatory diseases (55.6% (65/117) and 72.4% (21/29)). Conclusions: Infectious disease is still the main cause of FUO in children and the boys are more susceptible to infectious diseases. However, the morbidity of non-infectious inflammatory diseases increases to number 1 in FUO of children over 6 years of age.

Objective The aim of this study was to study the antibiotic resistance and resistance genes of methicillin-resistant Staphylococcus aureus (MRSA) in children from Shanghai area,and to determine the relationship between phenotypic and genotypic resistance profiles.Methods In this study,a total of 37 MRSA strains isolated from clinical specimens of hospitalized patients in Children's Hospital of Fudan University from March 2009 to November 2011 were collected.The mecA,ermA,ermB,ermC,aac (6') /aph (2"),aph (3')-Ⅲ,ant (4',4"),and qacA genes were detected by polymerase chain reaction (PCR).Resistance to antibiotics was detected by agar dilution tests.The data analysis was done by chi square test.Results Among the 37 MRSA isolates,all (100.0 ％) were mecA gene positive,9 (24.3％) were ermB gene positive,none was ermA/C gene positive,21 (56.8％) were aac (6')/aph (2") gene positive,10 (27.0％) were aph (3')-Ⅲ gene positive,6 (16.2％) were ant(4',4") gene positive,and 9 were qacA gene positive (24.3％).The positive rate of aac(6')/aph(2") in hospital acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) was significantly higher than that of community acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) (85.7％ vs18.8％,x2=60.340,P=0.000).Among the 37 MRSAisolates,37 (100.0％) were resistant to penicillin,ampicillin-sulbactam,cefazolin,cefoxitin and cefuroxime.The 37 isolates were all susceptible to teicoplanin,vancomycin,and linezolid.The resistant rates to gentamicin,erythromycin,clindamycin,sulfamethoxazole,fosfomycin,rifampicin,and levofloxacin were 51.4％ (19/37),81.1％ (30/37),51.4％ (19/37),16.2％ (6/37),27.0％ (10/37),37.8％ (14/37) and 54.0％ (20/37),respectively.Compared with CA-MRSA,HAMRSA isolates had significantly higher resistance rates to gentamicin (12.5％ vs 81.0％; x2 =17.033,P=0.000),levofloxacin (31.2％ vs 71.4％; x2 =5.903,P=0.017),and rifampin (6.2％ vs 61.9％; x2=11.959,P=0.001).The rate of gentamicin resistance in aac(6')/aph(2") gene carrying strains was significantly higher than strains not carrying the gene (x2 =29.757,P=0.000).Conclusions MRSA in children carry a variety of drug-resistant genes,showed multi-drug resistance.HA-MRSA carries more resistance genes,and has higher rates resistance to antimicrobials than CA-MRSA.

肿瘤细胞具有逃避免疫系统识别和攻击的能力,而这种能力正是肿瘤细胞与免疫系统相互作用的过程中所形成的.传统的肿瘤免疫监视学说已不能完全涵盖这一概念,因此Schreiber和Dunn等于2002年首次提出了肿瘤免疫编辑学说.肿瘤免疫编辑包括免疫监视和免疫逃逸.它反映了免疫系统具有抵抗肿瘤的保护性功能,同时又对肿瘤具有塑型作用,即对肿瘤细胞实施免疫选择压力,使弱免疫原性肿瘤细胞得以逃逸并进一步生长.肿瘤免疫编辑学说的提出不仅具有重要的理论意义,同时对肿瘤的免疫治疗也具有指导作用.

目的:建立人早孕期绒毛细胞滋养细胞(villous cytotrophoblasts,VCT)及绒毛外细胞滋养细胞(extravillous cytotrophoblasts,EVCT)的分离、培养方法.方法:利用不同的胰酶消化条件,收集人早孕期绒毛组织的VCT及EVCT并分别培养.倒置显微镜、扫描电镜观察VCT及EVCT的形态学特征;免疫细胞化学鉴定细胞来源及纯度.结果:胰酶短期、温和消化获得的EVCT,可生长于Matrigel包被的培养器皿上,并表达特异性标志物c-crbB-2;延长消化时间、增加胰酶浓度获得的VCT,种植于塑料或玻璃培养器皿上可聚集并融合形成合体滋养细胞.VCT不表达c-crbB-2.结论采用不同的胰酶消化及体外培养条件,可简单、快捷地分别获得高纯度人早孕期VCT及EVCT.

目的:研究HIV-1协同受体CXCR4、CCR5及CXCR4的特异性配体SDF-1在人胎盘组织的表达,探索HIV-1子宫内垂直传播的分子机制.方法:半定量RT-PCR检测早、中、晚孕期胎盘及早孕滋养细胞CXCR4、CCR5 mRNA水平;免疫组化和免疫细胞化学检测早孕胎盘及原代培养滋养细胞CXCR4、CCR5蛋白表达;原位杂交及免疫组化分析SDF-1在早孕胎盘的表达;ELISA测定滋养细胞SDF-1的动态分泌水平.结果:各孕期胎盘表达CXCR4及CCR5 mRNA;CXCR4蛋白定位于滋养细胞,而CCR5蛋白定位于绒毛基质中.滋养细胞可转录并翻译SDF-1,且能分泌可溶性SDF-1.结论:滋养细胞同时表达CXCR4及SDF-1,SDF-1可能通过降调CXCR4而拮抗X4-HIV-1感染胎儿细胞;R5-HIV-1或许能通过滋养层裂隙感染CCR5+基质细胞和/或Hofbauer细胞,从而发生子宫内垂直传播.

目的:研究早孕期绒毛组织及滋养细胞18种趋化因子受体的转录水平,以揭示趋化因子受体在母-胎界面生理性调节作用.方法:提取人早孕期绒毛组织及滋养细胞总RNA,半定量RT-PCR检测绒毛组织和滋养细胞18种趋化因子受体mRNA的表达水平.结果:CXCR4及CXCR6在绒毛组织中普遍高表达;CCR6、CCR7、XCR1及CX3CR1呈普遍中等表达;CCR1～CCR5、CCR8～CCR10、CXCR1～CXCR3在部分绒毛组织中表达,部分绒毛组织不表达或表达量很低;早孕人绒毛组织不表达CXCR5.早孕期滋养细胞表达CCR1、CCR3～CCR5、CCR8～CCR9、CXCR1～CXCR4、CXCR6、XCR1、CX3CR1;不表达CCR2、CCR6、CCR7、CCR10及CXCR5.结论:早孕期绒毛组织及滋养细胞表达多种趋化因子受体,它们在正常妊娠中具有重要的生理学意义.

趋化性细胞因子(chemokine)及其受体在生理及病理情况下对白细胞间交流及移行起至关重要的作用,调控着白细胞在血管、淋巴及其他组织、器官间的迁移和募集.自1996年发现趋化性细胞因子受体CCR5和CXCR4是HIV-1感染人T淋巴细胞的协同受体后,对趋化性细胞因子及其受体的研究不断深入.

母-胎界面的滋养细胞、蜕膜淋巴细胞和蜕膜基质均表达多种趋化因子及其受体.滋养细胞分泌的MIP-lα募集外周血中CD56brightNK细胞至母-胎界面;蜕膜血管表达SLC,特异性趋化CD56brightNK细胞.除募集蜕膜淋巴细胞外,母-胎界面的趋化因子及其受体尚参与固有免疫应答,并调节滋养细胞侵袭、分化及胎盘形成.滋养细胞固有表达CXCR4和CCR5,HIV-1利用CXCR4或CCR5人侵胎儿细胞,导致HIV-1经子宫垂直传播.滋养细胞及蜕膜细胞分泌的IL-8在炎症相关的早产中具有重要作用.