Aim To explore the effects of Huannao Yicong decoction(HYD)on the learning and memory ability and brain iron metabolism in APP/PS1 mice and the correlation of HAMP knockout mice and APP/PS1 double transgenic model mice.Methods The ex-periment was divided into five groups,namely,HAMP-/-group(6-month HAMP gene knockout mice),APP/PS1 group(6-month APP/PS1-double-transgenic mice),HAMP-/-+HYD,APP/PS1+HYD,and negative control group(6-month C57BL/6J mice),with six mice in each group.The dose was ad-ministered(13.68 g·kg-1 weight),and the other groups received distilled water for gavage once a day for two months.After the administration of the drug,the mice in each group were tested for learning and memory in the Morris water maze;Biochemical detec-tion was performed to detect iron ion content in each mouse brain;Western blot and RT-qPCR were carried out to analyze hippocampal transferrin(TF),transfer-rin receptor1(TFR1),membrane iron transporter1(FPN1)divalent metal ion transporter 1(DMT1)and β-amyloid protein(Aβ)protein and mRNA expression levels in each group.Results Compared with the normal group,both HAMP-/-mice and APP/PS1 mice had reduced the learning and memory capacity,in-creased iron content in brain tissue,Aβ protein ex-pression increased in hippocampus of HAMP-/-group and APP/PS1 group mice(P＜0.01),the protein and mRNA expression of TF,TFR1 and DMT1 increased in hippocampal tissues of HAMP-/-and APP/PS1 groups(P＜0.01),and the FPN1 protein and mRNA expres-sion decreased(P＜0.01).Compared with the HAMP-and APP/PS1 groups,respectively,HAMP-/-+HYD group and APP/PS1+HYD group had improved learning and memory ability,decreased iron content,decreased Aβ protein expression(P＜0.01),decreased TF,TFR1,DMT1 protein and mR-NA expression(P＜0.01),and increased expression of FPN1 protein and mRNA(P＜0.01).Conclusions There is some association between HAMP-/-mice and APP/PS1 mice,HYD can improve the learning and memory ability of HAMP-/-and APP/PS1 mice and reduce the Aβ deposition.The mechanism may be related to the regulation of TF,TFR1,DMT1,FPN1 expression and improving brain iron overload.

This study was aimed at understanding the detection rate,drug resistance characteristics,virulence characteris-tics,multi-locus sequence typing,and other molecular epidemic and pathogenic characteristics of Campylobacter jejuni and Campylobacter coli in children in Guangdong Province from 2020 to 2022.Anal swabs or stool samples of suspected infection cases in children from 2020 to 2022 were collected from two hospitals in Guangzhou,Guangdong Province.Campylobacter was isolated and cultured through the filtration method,and identified with a microbial mass spectrometry system;antibiotic resist-ance was analyzed with the agar dilution method;bacterial genome nucleic acids were extracted,and whole-genome sequencing was conducted;and drug resistance genes,virulence genes,multi-locus sequence typing,and phylogenetic analysis based on whole-genome single nucleotide polymorphisms were analyzed from whole-genome sequencing results.First,53 strains of Campy-lobacter were detected through continuous routine monitoring in this study,with a positive detection rate of 2.94％.Among them,Campylobacter jejuni accounted for 81.13％(43/53)and Campylobacter coli accounted for 18.87％(10/53).In addition,16 strains of Campylobacter were screened through multi-pathogen surveillance,including 11 strains of Campylobacter jejuni and 5 strains of Campylobacter coli.Drug resistance ex-periments and whole genome sequencing were conducted on 46 Campylobacter isolates,including 33 isolates of Campylobacter jejuni and 13 isolates of Campylobacter coli.The resistance rate of Campylobacter to erythromycin,a widely used clinical treatment,was21.73％(10/46);that to tetracycline was 80.43％(37/46);those to the quinolone antibiotics nalidixic acid and ciprofloxacin were 76.08％(35/46)and 71.73％(33/46)respectively;and that to chloramphenicol was lowest,at 2.17％(1/46).The drug resistance rate was generally higher for Campylobacter coli than Campylobacter jejuni,and the differences in the indicators of erythromycin,gentamicin,streptomycin,telithromycin,and clindamycin were statistically significant.A total of 30 isolates of multidrug-resistant Campylobacter were detected,including nine multidrug-resistant phenotypes.Whole-ge-nome sequence analysis indicated that 46 Campylobacter isolates carried antibiotic resistance genes for antibiotics such as quino-lones,tetracyclines,β-lactams,and aminoglycosides,and carried 128 virulence factor genes in five categories.All 46 isolates of Campylobacter were identified as 35 ST type through MLST typing,and phylogenetic analysis indicated no obvious dominant ST type.Campylobacter coli had more SNPs than Campylobacter jejuni.In conclusion,the positive detection rate of Campy-lobacter in Guangzhou City,Guangdong Province stabilized from 2020 to 2022,and the detection rate of Campylobacter jejuni was higher than that of Campylobacter coli.Campylobacter isolates were resistant to tetracyclines and quinolone,and showed a wide spectrum of multi-drug resistance,which was relatively severe among Campylobacter coli.Resistance genes and drug-resistant phenotypes were correlated and had predictive significance.The virulence genes of Campylobacter jejuni were more a-bundant than those of Campylobacter coli,possibly because of the higher detection rate and pathogenicity of Campylobacter jejuni.The phylogenetic tree showed clear branches with high genetic diversity and no clearly dominant clonal group.

In mass spectrometry-based proteomics experiments,achieving high-throughput and efficientproteolytic digestion is crucial to ensure optimal protein cleavage and enhance the depth of protein identi-fication (including the number of identified proteins and the coverage of protein amino acid sequences) .Trypsin is the most widely used protease in mass spectrometry-based proteomics due to its ability to spe-cifically cleave the carboxyl terminus of arginine and lysine.However,it was found that Trypsin has some missed enzymatic efficiency for the cleavage of lysine residues.Therefore,in actual proteomics sample preparation,a combination of Trypsin and LysC will be used to ensure adequate cleavage of lysine resi-dues.Our study revealed that the commonly employed LysC-Trypsin tandem cleavage method exerts an impact on the enzymatic cleavage of protein samples by Trypsin due to the subsequent cleavage of Trypsin by initially added LysC.Consequently,we adjusted the order of LysC and Trypsin tandem digestion,with Trypsin cleavage being performed first followed by the addition of LysC to target any missed lysine resi-dues.We comprehensively compared and analyzed three distinct sequential digestion methods,namely Trypsin-Trypsin (T-T),LysC-Trypsin (L-T),and Trypsin-LysC (T-L),in terms of their effects on pro-tein sample preparation quality.The results demonstrated that the Trypsin-LysC sequential digestion ap-proach not only minimizes missed protein lysine/arginine cleavage sites without increasing experimental costs,at the same time yielding peptides with a moderate amino acid sequence length.The use of Tryp-sin-LysC digestion enhances the adsorption and separation of peptide samples in RP-HPLC,as well as improves the depth of protein detection and amino acid sequence coverage during tandem mass spectrome-try analysis.This research work offers a novel technical solution and serves as a valuable reference for proteome sample preparation.

Objective:This study aims to evaluate the impact of Diagnosis-Related-Groups(DRGs)payment on the average total cost,length of stay,service volume,effectiveness,and characteristics of traditional Chinese medicine(TCM)hospitals.Methods:A national medical center specializing in TCM was selected as the research subject.The Difference-in-Difference Model(DID)was utilized to analyze the differences in various indicators between insured patients(intervention group)and uninsured patients(control group)before and after the implementation of the payment reform policy.The reliability and stability of the model were verified through parallel trend tests and placebo tests.Results:The coefficients of DID interaction terms for eleven indicators including average total hospitalization cost,number of cases,length of stay,proportion of medical service revenue,and proportion of herbal medicine revenue were significant(P<0.05).The DID interaction term coefficients for four indicators including herbal medicine usage rate and proportion of non-pharmacological TCM therapy revenue were not significant(P>0.05).Conclusion:DRG payment significantly reduced the per-admission cost,with significant decreases in consumables and medical technology expenses,optimizing cost structure,and a slight decrease in the proportion of herbal medicine costs.It is necessary to further expand the sample size,track policy impacts,and comprehensively evaluate the effects of DRG payment on TCM hospitals in China.

Objective To investigate the performance of brands and types of high-flow nasal cnnula oxygen therapy(HFNC)devices at different altitudes.Methods Four different models of HFNC devices,including R-80S bi-level non-invasive ventilator integrated with HFNC device,HF-60A HFNC device,HFT-300 HFNC device and H-80A HFNC device,were connected with the gas flow meter,simularted head and QuickLung and then put into a low-pressure chamber.The flow rates of the HFNC devices were set to 10,15,20,25,30,35,40,45,50,55 and 60 L/min,and the simulated altitudes of the low-pressure chamber were set to 6 000,5 000,4 000,3 000,2 000,1 000 and 0 m.The actual output airway flow rates,airway pressure changes and trends of the four HFNC devices were recorded at different setting altitudes and flow rates.SPSS 25.0 software was used for statistical analysis.Results The actual output airway flow rates of the four HFNC devices showed an increasing trend as the altitude rose with the simulated altitude of 6 000 m and the setting flow rate kept constant,which increased slowly and even went to decrease when the altitude and flow rate exceeded some limits.The degree of changes in the flow rate with the increasing altitude varied,and there was no uniform pattern.With the rising of altitude,the actual output airway pressure of the four HFNC devices with the flow rate raning from 10 to 35 L/min also increased gradually,which showed a decreasing trend(turning point)after going up to some certain value when the flow rate exceeded 35 L/min,and the altitude where the turning point appeared was lowered as the flow rate increased.Conclusion The actual output airway flow rates and airway pressure during HFNC rise at a high-altitude environment,and generally considerations have to be taken on required airway pressure,patient comfort and the altitude of the patient's usual place of residence when setting the flow rates of the HFNC device.[Chinese Medical Equipment Journal,2024,45(6):49-58]

Objective To study the in vitro expression of three phenylalanine hydroxylase(PAH)mutants(p.R243Q,p.R241C,and p.Y356X)and determine their pathogenicity.Methods Bioinformatics techniques were used to predict the impact of PAH mutants on the structure and function of PAH protein.Corresponding mutant plasmids of PAH were constructed and expressed in HEK293T cells.Quantitative reverse transcription polymerase chain reaction was used to measure the mRNA expression levels of the three PAH mutants,and their protein levels were assessed using Western blot and enzyme-linked immunosorbent assay.Results Bioinformatics analysis predicted that all three mutants were pathogenic.The mRNA expression levels of the p.R243Q and p.R241C mutants in HEK293T cells were similar to the mRNA expression level of the wild-type control(P>0.05),while the mRNA expression level of the p.Y356X mutant significantly decreased(P<0.05).The PAH protein expression levels of all three mutants were significantly reduced compared to the wild-type control(P<0.05).The extracellular concentration of PAH protein was reduced in the p.R241C and p.Y356X mutants compared to the wild-type control(P<0.05),while there was no significant difference between the p.R243Q mutant and the wild type control(P>0.05).Conclusions p.R243Q,p.R241C and p.Y356X mutants lead to reduced expression levels of PAH protein in eukaryotic cells,with p.R241C and p.Y356X mutants also affecting the function of PAH protein.These three PAH mutants are to be pathogenic.[Chinese Journal of Contemporary Pediatrics,2024,26(2):188-193]

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.

The ICR(Institute of Cancer Research)mouse infection model was constructed to study the pathogenicity of Sal-monella Telelkebir serotype,and the pathogenic identification of mouse isolates was carried out.Observe the bacterial excretion cycle,evaluate the pathogenicity of Salmonella serotype to mice,and calculate the LD50 by the changes in clinical characteris-tics,histopathology and tissue bacterial load of infected mice;by flight mass spectrometry,biochemical identification,serotype identification,molecular typing and other experiments,compared with human isolates;virulence gene analysis was carried out by PCR experiment and whole genome sequencing.The LD50 of Salmonella Telelkebir is 2.67 × 108 CFU/mL;curling and fluffing may occur 0.5 h after infection;autopsy of dead mice showed that the small intestine was severely congested,with more bubbles and fluid accumulation,cecal necrosis,liver apical degeneration and necrosis,necrotic foci on the surface of the kidney and spleen atrophy;the bacterial load of spleen,kidney,lung,liver and jejunum in mice reached its peak at 3 days after infection,while that of heart at 6 days;the bacterial excretion time of the high-dose group exceeded 100 days;The level of CD3 in tissues increased with increasing dose,with inflammatory cell infiltration,myocardial capillary dilation and hyperemia,large area of vacuoles,degeneration and necrosis of hepatocytes,obvious enlargement of splenic sinus,blurred zoning,thickening of glomerular basement membrane,partial exfoliation of ciliated epithelium,atrophy and exfoliation of jejunal villi;PCR and whole genome sequencing revealed Salmonella-related virulence genes such as cdtB,plt A and pltB.This study was the first to successfully establish the ICR mouse model of Salmonella Telelkebir,demonstrating that this serotype of Salmonella has some pathogenicity.

Objective To evaluate the effects of high-fat diet on the pharmacokinetics of metronidazole in Chinese healthy adult subjects.Methods This program is designed according to a single-center,randomized,open,single-dose trial.Forty-seven healthy subjects were assigned to receive single dose of metronidazole tablets 200 mg in either fasting and high-fat diet state,and blood samples were taken at different time points,respectively.The concentrations of metronidazole in plasma were determined by high performance liquid chromatography-mass spectromentry.Results The main pharmacokinetic parameters of metronidazole in fasting state and high-fat diet state were as follows:Cmax were(4 799.13±1 195.32)and(4 044.17±773.98)ng·mL-1;tmax were 1.00 and 2.25 h;t1/2 were(9.11±1.73)and(9.37±1.79)h;AUC0_t were(5.59±1.19)x 104 and(5.51±1.18)x 104 ng·mL-1·h;AUC0_∞ were(5.79±1.33)x 104 and(5.74±1.32)× 104 ng·mL-1·h.Compared to the fasting state,the tmaxof the drug taken after a high fat diet was delayed by 1.25 h(P＜0.01),Cmax,AUC0_t,AUC0-∞ were less or decreased in different degrees,but the effects were small(all P＞0.05).Conclusion High-fat diet has little effects on the pharmacokinetic parameters of metronidazole,which does not significantly change the degree of drug absorption,but can significantly delay the time to peak.

Objective To evaluate the bioequivalence of metronidazole tablet and reference formulation in Chinese healthy subjects.Methods A single-dose,two-cycle,randomized,open,self-crossover trial was designed with 48 healthy subjects randomly assigned to fasting or postprandial group.For each group,a single oral dose of metronidazole tablet(200 mg)or a reference preparation(200 mg)per cycle were enrolled.The concentration of metronidazole in plasma was measured by high performance liquid chromatography tandem mass spectrometry(HPLC-MS/MS).The non-compartmental model was applied to calculate the pharmacokinetic parameters for bioequivalence analysis via SAS 9.3 software.Results The main pharmacokinetic parameters of test and reference metronidazole tablets in the fasting group were as follows,the Cmax were(4 855.00±1 383.97)and(4 799.13±1 195.32)ng·h·mL-1;the AUC0-t were(54 834.68±12 697.88)and(55 931.35±11 935.28)ng·h·mL-1;the AUC0-∞ were(56 778.09±13 937.76)and(57 922.83±13 260.54)ng·h·mL-1;the Tmax were respectively 1.17 and 1.00 h;t1/2 were(8.99±1.76)and(9.11±1.73)h,respectively.The ratio of the geometric mean and its 90％confidence intervals(CI)of Cmax,AUC0-t and AUC0-∞ were all within the equivalent interval of 80.00％-125.00％.As for postprandial conditions,the main pharmacokinetic parameters of test and reference metronidazole tablets were as follows,the Cmax were(4 057.08±655.08)and(4 044.17±773.98)ng·h·mL-1;the AUC0-t were(55 956.42±12 228.12)and(55 121.04±11 784.55)ng·h·mL-1;the AUC0-∞ were(58 212.83±13 820.00)and(57 350.38±13 229.46)ng·h·mL-1;the Tmax were 2.50 and 2.25 h;the t1/2 were(9.37±1.68)and(9.37±1.79)h,respectively.The ratio of the geometric mean and 90％CI of Cmax,AUC0-t and AUC0-∞ were all within the equivalent interval of 80.00％-125.00％.Conclusion The two preparations were bioequivalent to Chinese healthy adult volunteers under both fasting and fed conditions.