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 establish a inductively coupled plasma-mass spectrometry(ICP-MS)method for 7 elemental impurities,cadmium(Cd),lead(Pb),arsenic(As),mercury(Hg),cobalt(Co),vanadium(V)and nickel(Ni)in medicinal excipient potassium sorbate according to the latest requirement of The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use(ICH)Q3D.Methods After dissolving the sample with 2％nitric acid solution,the potassium sorbate sample was digested by closed ultra-high pressure microwave digestion technology,and the elements rhenium(Re),rhodium(Rh),germanium(Ge),scandium(Sc)and bismuth(Bi)were used as internal standards to correct the matrix interference and drift.Results The 7 elements showed good linearity in the specified concentration range(r＞0.998 0).The detection limits were between 0.002-0.042 ng/g,the recovery rates were between 85％-106％,and the RSDs of each element precision were＜5％.The content of elemental impurities in 13 batches of domestic and imported potassium sorbate samples from different manufacturers was determined legally,and none exceeded the limit,which was in line with the provisions of ICH.Conclusion The established method is simple,accurate,sensitive,specific and reproducible.In this test,the elemental impurity residues in potassium sorbate are screened,which can not only grasp the overall quality level of potassium sorbate,but also ensure the safety of potassium sorbate as medicinal excipients,and provides a methodological basis for the revision of the Chinese Pharmacopoeia.

Objective:To investigate the mechanism of excessive inflammation in the lung of C3H/HeN(C3H) mice following Chlamydia muridarum(Cm) airway infection.Methods:Chlamydial pneumonitis was induced in C3H and C57BL/6(C57) mice by intranasal inoculation with 1×103IFU (inclusion forming unites) of Cm strains.The expression of TLR2,TLR4 and MyD88 mRNA in the lung at different time point post-infection was measured by RT-PCR.Results:Cm infection induced Toll-like receptors expression in two strains of mice.The expression of TLR2 and TLR4 mRNA,especially TLR2 mRNA(P<0.001 or P<0.05),were significantly higher in highly susceptible C3H mice on day 7 and day 14 d post-infection compared with C57 mice.Further studies showed that the expression of MyD88 mRNA was also significantly higher in C3H mice on day 7 post-infection,and maintained high expression untill the day 14.Conclusion:Cm lung infection induced high level of TLR2,TLR4 and MyD88 mRNA expression in C3H mice,which may associate with excessive inflammation in C3H mice.

Objective To study the effects of ibuprofen on the growth and development of oligodendrocytes. Methods A total of 6 clean and healthy adult female SD (Sprague Dawley) rats were used for extracting and culturing of oligodendrocytes(OLs).Lysophosphatidic acid(LPA)was then added,and the morphological changes of OLs pre-treatment and post-treatment were observed. Then 6 newborn rats (born 24-48 h) were used for mixed glial cell extraction from the cortex, then the OPCs were inoculated into the culture plates and randomly divided into control group, ibuprofen group, lysophosphatidic acid(LPA)group and LPA+ibuprofen group.After the adhering of the cells in each group for three days, cell morphology was observed,and the drugs were added as interventions.The control group was treated with normal saline, and the other 3 groups were added with saline solution of ibuprofen(100 μmol/L),LPA(1.0 μmol/L)and the mixture of them. The cell morphological changes were observed after 7-day intervention.The morphology of OPCs and OLs were observed by immunofluorescence staining through OPCs'specific immune markers (platelet-derived growth factor receptor alpha, PDGFR-α)and OLs'specific immune markers(myelin basic protein,MBP)along with cell count of mature OLs.Western blot assay was used to detect the relative expression level of MBP in each group. Results After the treatment with LPA to the mature OLs,protrusions were shrinking and became very sparse.The morphology of cells developed well in each group after cell adhering for 3 days. After drug intervention for 7 days, more cell protrusions and branches were observed in ibuprofen group and LPA+ibuprofen group than those of the control group and LPA group.The results of cell count showed that the number of MBP positive cells was significantly higher in the ibuprofen group and LPA+ibuprofen group than that in the control group and LPA group(P<0.01).The results of Western blot assay showed that the MBP protein expression was significantly less in LPA group than the other three groups (P<0.01), and the expression was significantly higher in the ibuprofen group than that of LPA+ibuprofen group (P<0.01). Conclusion LPA has a toxic effect on the growth and development of OPCs, and it has an inhibitory effect on the normal growth of mature OLs. A certain concentration of ibuprofen can significantly inhibit the cytotoxicity of LPA on OPCs and OLs,and promote the formation and maintenance of mature OLs.