Aim To establish a stable hepatic stellate cell ( HSC ) -specific G protein-coupled receptor kinase 2 ( GRK2 ) knockout mice and provide the important animal model for further studying the biological function of GRK2 in HSC. Methods The loxP-labeled Grk2 gene mouse (Grk2

Aim To investigate the therapeutic effect of the MW-9 on ulcerative colitis(UC)and reveal the underlying mechanism, so as to provide a scientific guidance for the MW-9 treatment of UC. Methods The model of lipopolysaccharide(LPS)-stimulated RAW264.7 macrophage cells was established. The effect of MW-9 on RAW264.7 cells viability was detected by MTT assay. The levels of nitric oxide(NO)in RAW264.7 macrophages were measured by Griess assay. Cell supernatants and serum levels of inflammatory cytokines containing IL-6, TNF-α and IL-1β were determined by ELISA kits. Dextran sulfate sodium(DSS)-induced UC model in mice was established and body weight of mice in each group was measured. The histopathological damage degree of colonic tissue was assessed by HE staining. The protein expression of p-p38, p-ERK1/2 and p-JNK was detected by Western blot. Results MW-9 intervention significantly inhibited NO release in RAW264.7 macrophages with IC50 of 20.47 mg·L-1 and decreased the overproduction of inflammatory factors IL-6, IL-1β and TNF-α(P<0.05). MW-9 had no cytotoxicity at the concentrations below 6 mg·L-1. After MW-9 treatment, mouse body weight was gradually reduced, and the serum IL-6, IL-1β and TNF-α levels were significantly down-regulated. Compared with the model group, MW-9 significantly decreased the expression of p-p38 and p-ERK1/2 protein. Conclusions MW-9 has significant anti-inflammatory activities both in vitro and in vivo, and its underlying mechanism for the treatment of UC may be associated with the inhibition of MAPK signaling pathway.

OBJECTIVE To establish the analysis methods of 33 banned pesticides in Ginkgo Biloba leaves and the extracts, and conduct the risk assessment study. METHODS One hundred and thirty-six batches of Ginkgo Biloba leaves and 58 batches of Ginkgo Biloba leaves extract were detected by UPLC-MS and GC-MS. The acute and chronic intake risk of pesticide residues in samples were calculated by point assessment method, and the risk scores of the pesticides were calculated by the Britain veterinary residues matrix ranking. RESULTS Six kinds of banned pesticides were detected in 136 batches of Ginkgo Biloba leaves, the total detection rate was 35.29%, and the detection amount was 0.002−0.210 mg·kg−1. The chronic dietary intake risk was 0.018%−0.620%, and the acute dietary intake risk was 0.000 1%−0.014 0%, indicated that the dietary exposure risk of pesticides in Ginkgo biloba leaves was at a low level. Two kinds of banned pesticides were detected in 58 batches of Ginkgo Biloba leaves extract, the detection rate was 55.17%, and the detection amount was 0.002−1.788 mg·kg−1. The percentage of acceptable daily intake was 0.003%−0.143%, and the percentage of acute reference dose was 0.002 4%, which was also at a low level. Risk ranking results indicated that the risk of phorate was the highest and should be focused on the production and safety supervision. CONCLUSION The method has good stability, high precision and promising repeatability, which can be used for the detection of 33 prohibited pesticides in Ginkgo biloba leaves and their extracts. The results show that the residual amounts of 33 banned pesticides in Ginkgo Biloba leaves and its extracts were extremely low, and there is no significant health risks.

Celastrol and wilforlide A are the main active triterpenoids of the traditional Chinese medicine Lei Gong Teng, which have anti-tumour, anti-inflammatory and immunosuppressive activities, and are the material basis for the clinical efficacy of Lei Gong Teng-related Chinese medicinal preparations. By analysing the biosynthetic pathway of active ingredients, optimizing genetic elements and utilizing "cell factory" to produce triterpenoids heterologously will be an effective way to obtain from Tripterygium wilfordii in the future in a "low-cost and high-efficient" manner. CYP712Ks are the first cytochrome P450s involved in the skeleton modification of friedelane-type and oleanane-type triterpenoids in T. wilfordii, and they can catalyse the generation of polpunonic acid from friedelin and 3-epi-katonic acid from β-amyrin by carboxylation at C-29 position. In this study, four multifunctional TwCYP712K1/2/3/5 were used to clarify the catalytic function and substrate selection preference using in vivo functional characterization in Saccharomyces cerevisiae. The spatial structure of the protein-substrate binding was clarified through homology modeling and molecular docking, and then the differential amino acids in the active pocket of the protein were mutated to clarify the crucial amino acids determining the catalytic function and the selection of substrate structure. A total of 63 mutant elements were constructed, and the amino acid sites affecting the carboxylation function of TwCYP712Ks were analyzed. In particular, the key amino acids affecting the substrate selectivity of TwCYP712K2 towards oleanane-type and friedelane-type triterpenoids were revealed and the TwCYP712K2^F127I and TwCYP712K2^A227T mutants would result in a reversal of the product ratio. In conclusion, four proteins of TwCYP712Ks were semi-rationally designed by homologous protein alignment and mutual mutation to elucidate multiple amino acid sites determining the catalytic function of the proteins, and a series of activity-enhancing or altering mutants were obtained, which provide abundant catalytic elements for the biosynthesis of active triterpenoids from T. wilfordii, and the mechanism of carboxylation in the C-29 position was initially elucidated.

AIM To analyze the metabolites of nobiletin in rats in vivo based on characteristic ions.METHODS Ten rats were assigned into administration group and control group,and given intragastric administration of the 0.5％CMC-Na suspension of nobiletin(250 mg/kg)and 0.5％CMC-Na solution,respectively,after which plasma,urine and feces were collected,solid phase extraction method was adopted in pretreatment,UHPLC-HRMS analysis was performed.The candidate metabolites were systematically described according to diagnostic product ions,chromatographic retention time,accurate molecular weight and neutral loss fragments,after which accurate metabolites were obtained in the established metabolite data set with-CH3(m/z 15)characteristic ions as a baits.RESULTS A total of 64 metabolites were identified,whose main metabolic pathways were glucuronidation,sulfation,hydrogenation and their compound reactions.CONCLUSION This experiment elucidates the metabolites of nobiletin in rats in vivo,which provides a new reference for its further development.

AIM To optimize the extraction process for uracil,hypoxanthine,xanthine,uridine,thymine,inosine,guanosine and 2'-deoxyguanosine from Pheretima guillelmi(Michaelsen),and to determine their contents.METHODS With solid-liquid ratio,ultrasonic time and ultrasonic temperature as influencing factors,contents of hypoxanthine and total nucleosides as evaluation indices,the extraction process was optimized by orthogonal test.HPLC was adopted in the content determination of varioud nucleosides,the analysis was performed on a 30℃thermostatic Agilent C18 column(4.6 mm×250 mm,5 μm),with the mobile phase comprising of methanol-water flowing at 1 mL/min in a gradient elution manner,and the detection wavelength was set at 260 nm.RESULTS The optimal conditions were determined to be 1∶250 for solid-liquid ratio,60 min for ultrasonic time,and 60℃for ultrasonic temperature.Eight nucleosides showed good linear relationships within their own ranges(R2＞0.999 0),whose average recoveries were 99.11%-103.27%with the RSDs of 0.85%-2.89%.CONCLUSION This stable and reliable method can be used for the extraction and content determination of nucleosides from P.guillelmi.

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 monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Aim To investigate the mechanisms of Ke-chuanting granules(KCT)inhibiting the IL-33/ILC2s pathway and pathogenic T cells to intervene in allergic airway inflammation.Methods Network pharmacolo-gy was utilized to analyze the potential targets and mechanisms of KCT-treated asthma.Allergic asthma models were induced in mice using OVA.Lung histo-pathology was conducted to observe injury changes.ELISA and quantitative PCR were utilized to measure key inflammatory factors and their mRNA expression levels in Th2-type asthma.Western blot was used to detect the phosphorylation levels of relevant proteins in the MAPK pathway.Flow cytometry was performed to evaluate the proportions of ILC2s,Th1,Th 17,Th2 and Treg cells.Results Network pharmacology iden-tified 227 main active components and 143 key targets of KCT in treating asthma,primarily enriched in signa-ling pathways such as MAPK and IL-17.Further vali-dation experiments demonstrated that KCT significantly alleviated lung inflammatory injury in asthmatic mice,reduced the number of B cells,production of I L-4,TNF-α and TGF-β,downregulated JNK phosphoryla-tion levels in lung tissue,as well as mRNA levels of Il-33,Bcl11b,Rorα,Tcf-7,Jun,Mapk3 and Mapk14.KCT intervention reduced the numbers of ILC2s and Th 17 cells in lungs and spleens of mice,and inhibited Th2 cell infiltration in lungs.Conclusions KCT ex-hibits therapeutic effects on allergic airway inflamma-tion in asthma,closely associated with the inhibition of the IL-33/ILC2s pathway,pathogenic T cell subsets,and JNK-MAPK signaling pathway.

Metabolic dysfunction-associated fatty liver disease (MAFLD) is an increasingly common liver disease worldwide. MAFLD is diagnosed based on the presence of steatosis on images, histological findings, or serum marker levels as well as the presence of at least one of the three metabolic features: overweight/obesity, type 2 diabetes mellitus, and metabolic risk factors. MAFLD is not only a liver disease but also a factor contributing to or related to cardiovascular diseases (CVD), which is the major etiology responsible for morbidity and mortality in patients with MAFLD. Hence, understanding the association between MAFLD and CVD, surveillance and risk stratification of MAFLD in patients with CVD, and assessment of the current status of MAFLD management are urgent requirements for both hepatologists and cardiologists. This Taiwan position statement reviews the literature and provides suggestions regarding the epidemiology, etiology, risk factors, risk stratification, nonpharmacological interventions, and potential drug treatments of MAFLD, focusing on its association with CVD.