A growing body of research points out that gut microbiota plays a key role in tumor immunotherapy. By optimizing the composition of intestinal microbiota, it is possible to effectively improve immunotherapy resistance and enhance its therapeutic effect. This article comprehensively analyzes the mechanism of intestinal microbiota influencing tumor immunotherapy resistance, expounds the current strategies for targeted regulation of intestinal microbiota, such as traditional Chinese medicine and plant components, fecal microbiota transplantation, probiotics, prebiotics and dietary therapy, and explores the potential mechanisms of these strategies to improve patients' resistance to tumor immunotherapy. At the same time, the article also briefly discusses the prospects and challenges of targeting intestinal microbiota to improve tumor immunotherapy resistance, which provides a reference for related research to help the strategy research of reversing tumor immunotherapy resistance.

Objective: To establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method based on solid-phase extraction column purification for simultaneous determination of cyromazine and melamine in poultry eggs and meat. Methods: Eggs, quail eggs, and chicken were collected from markets. After homogenization, the sample was extracted with 0.5% formic acid in acetonitrile, subjected to solid-phase extraction using an MCX cartridge, and eluted with 5% ammonia in methanol. The eluate was collected, evaporated to near dryness under nitrogen, and reconstituted in a 10% aqueous methanol solution. Separated using TSK gel Amide-80 column (2.0 mm×150 mm, 5 μm), cyromazine and melamine were simultaneously detected in positive ion multiple reaction monitoring mode via tandem mass spectrometry, with quantification achieved by isotope dilution internal standard methods. Efficiency was enhanced and matrix interference minimized by optimizing conditions such as sample extraction, solid-phase extraction cartridge selection, and instrumental parameters. Calibration curves were constructed, and detection limits, quantification limits, spiked recoveries, and relative standard deviations for (RSD) of cyromazine and melamine were calculated. Results: After method optimization, matrix effects for cyromazine and melamine ranged from 0.97 to 1.04, indicating no significant matrix suppression or enhancement. Both cyromazine and melamine exhibited excellent linearity within the concentration range of 1.0-200.0 ng/mL, with correlation coefficients ≥0.999 5. The limits of detection were 0.3 μg/kg for cyromazine and 0.5 μg/kg for melamine, the quantification limits were 1.0 and 1.5 μg/kg, respectively. At spiked levels of 1.0, 20.0, and 150.0 μg/kg, the average recoveries ranged from 78.6% to 103.1%, with RSD between 3.5% and 6.3%. Among 95 samples tested, cyromazine was detected in 6 samples and melamine in 5 samples; neither cyromazine nor melamine was detected in chicken samples. Conclusion The UPLC-MS/MS method established in this study enables simultaneous detection and accurate quantification of cyromazine and melamine in poultry eggs and meat.

OBJECTIVE: To distinguish the ambiguous genotyping results of human leukocyte antigen (HLA), identify a novel HLA-B allele and analyze the nucleotide sequence. METHODS: A total of 2 076 umbilical core blood samples from the Zhejiang Cord Blood Bank in 2022 were detected using the next generation sequencing technology (NGS) based on the Ion Torrent S5 platform. Among these a rare HLA-B allele with ambiguous combination result containing a base mutation was identified, and was further confimed by the third-generation sequencing (TGS) based on the nanopore technology. RESULTS: The NGS typing result of HLA-B locus showed HLA-B* 46:18, 54:06 or HLA-B*46:01, 54:XX (including a base mutation), and nanopore sequencing confirmed the typing as HLA-B*46:01, 54:XX (including a base mutation). Compared with HLA-B*54:01:01:01, the HLA-B*54:XX allele showed one single nucleotide substitution at position 1014 T>C in exon 6, with no amino acid change. The nucleotide sequence of the novel HLA-B*54:XX has been submitted to the GenBank nucleotide sequence database and the accession number OP853532 was assigned. CONCLUSION A ambiguous genotyping of the HLA-B Locus detected by NGS was distinguished by nanopore sequencing and a new HLA-B allele was successfully identified, which was officially named as HLA-B*54:01:11 by the World Health Organization Nomenclature Committee for Factors of the HLA System.
Humans ; High-Throughput Nucleotide Sequencing ; Alleles ; HLA-B Antigens/genetics* ; Genotype ; Mutation ; Sequence Analysis, DNA ; Base Sequence

Eleven compounds were isolated from the ethyl acetate fraction of the 95% aqueous ethanol extract of the roots of Sophora tonkinensis by silica gel, ODS, Sephadex LH-20 column chromatography, and semi-preparative RP-HPLC. Their structures were identified as 7-hydroxy-8-isopentenylchromone (1), furo[2,3-f]-1,3-benzodioxole-7-carboxylic acid (2), 6-[3-(2′,4′-dihydroxyphenyl)acryloyl]-7-hydroxy-2,2-dimethyl-8-(3-methyl-2-butenyl)-2H-benzopyran (3), flemichapparin B (4), tectorigenin (5), genistein (6), 6-hydroxy-1,3-benzodioxole-5-carboxylic acid (7), vanillic acid (8), protocatechuic acid (9), 2,4-dihydroxybenzoic acid (10), and p-hydroxybenzoic acid (11) through extensive spectroscopic data (IR, UV, HR-ESI-MS, and NMR spectra). Among them, compounds 1 and 2 were new compounds. In addition, compound 3 showed significant α-glucosidase and protein tyrosine phosphatase-1B (PTP1B) inhibitory activities with IC₅₀ values of 5.595 and 0.320 μmol·L^-1, respectively.

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 investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

Objective To establish an evaluation system of pathogen detection rate of hospitalized patients before antimicrobial treatment based on process and outcome indicators,and study its application effect.Methods Hospi-talized patients with therapeutic antimicrobial treatment in a tertiary first-class hospital from July 2022 to June 2023 were selected as the study objects.Difference in process and outcome indicators were compared between before(Ju-ly-December 2022,control group)and after(January-June 2023,intervention group)the implementation of inter-vention in the evaluation system for pathogen detection rate of hospitalized patients before antimicrobial treatment.Results 41 577 and 27 052 hospitalized patients received therapeutic antimicrobial agents were included in the inter-vention group and control group,respectively.Pathogen detection rate and the accurate pathogen detection rate in the intervention group were both higher than those in the control group(74.2％vs 62.8％and 90.3％vs 82.5％,respectively),both with statistically significant differences(both P＜0.001).The goal achievement rate and im-provement rate for pathogen detection rate were 237.5％and 18.2％respectively,the goal achievement rate and im-provement rate for accurate pathogen detection rate were 104.0％and 9.5％respectively.For the process indica-tors,the conformity rate of detection and diagnosis,accurate collection rate,timely transfer rate,acceptance rate of pathogen specimens in the intervention group were all higher than those in the control group,differences were all statistically significant(all P＜0.001).For the outcome indicators,detection rates of targeted indicators and blood culture specimens,pathogen detection rate before treatment of restricted and special grade antimicrobial agent,as well as detection rate of sterile body fluid specimens in the intervention group were all higher than those in the con-trol group,with statistical significance(all P＜0.05).In addition,the positive rate of blood culture specimens in-creased from 18.5％before intervention to 21.7％after intervention,with statistically significant difference(P＜0.05).Conclusion The establishment of indicator evaluation system can improve the detection rate and accurate detection rate of pathogens before antimicrobial treatment,as well as the management quality and connotation of indicators.

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.

This study was aimed at investigating the pathogenic and molecular characteristics of Klebsiella pneumoniae(KP)in fecal samples of diarrhea cases in a district of Beijing.Fecal samples from diarrhea cases in an outpatient department in a district of Beijing from 2018 to 2021 were collected,and used for isolation and culture of KP.The KP strains isolated strains were subjected to drug resistance phenotype testing and whole-genome sequencing.Multilocus sequence typing and whole-genome phyletic evolution analysis were performed on the sequencing results.The cases'epidemiological and clinical characteristics were analyzed.From 2018 to 2021,1 103 fecal samples were collected and detected.The total detection rate of KP was 10.43％(115/1 103),and the infection rate of KP mixed with other diarrhea-causing pathogens was 42.61％(49/115).The positivity rate was slightly high(12.47％,61/489)a-mong females and was highest in young adults 16-45 years of age.Small peaks were observed in January,April to May,and August to September.The gastrointestinal symptoms in cases were mainly nausea and watery stool,and the suspicious food was unknown.Ampicillin,tetracycline,and sulfafurazole were the top three antibiotics to which these 115 KP strains showed resistance,and 29 strains were resistant to multiple antibiotics.The strains were divided into 72 sequence types,among which ST23 was dominant.According to the phylogenetic tree,the strains were divided into four main branches,among which 14 ST23 strains had a very close genetic relationship with the highly virulent NTUH-K2044 reference strain.KP infection persisted in fecal samples from diarrhea cases in the district of Beijing.Women and young adults were particularly susceptible.The drug resistance of KP strains in this region was very serious,and the ST types were diverse.Moreover,the ST23 pathogenic strains were closely related to high virulence strains.