Amantadine(AMD)residue can accumulate in organisms through the food chain and cause serious harm to human body.AMD can specifically bind to AMD specific aptamer and cause its conformation to change from a random single strand to a stem-loop structure.To avoid the influence of excess nucleotides on binding of aptamer to AMD,the truncation of the AMD original aptamer J was optimized by retaining an appropriate stem-loop structure,and a new type of truncation aptamers was developed in this work.By comparing the truncated aptamer with the original aptamer,it was found that the truncated aptamer J-7 had better affinity and specificity with AMD.The detection limit of AMD was 0.11 ng/mL by using J-7 as specific recognition element and molybdenum disulfide nanosheet(MoS2Ns)as signal amplification element.The developed method base on truncated aptamer J-7 was used for detection of AMD in milk,yogurt and SD rat serum samples for the first time with recoveries of 86.6%-108.2%.This study provided a reference for truncating other long sequence aptamers and provided a more sensitive detection method for monitoring AMD residues in food.

Objective To investigate the effect and mechanism of pomalidomide(POM)on airway inflammation and mucus hypersecretion in rats with chronic obstructive pulmonary disease(COPD).Methods Thirty-six SD rats were randomly divided into control group,model group and POM group,with 12 in each group,half male and half female.The COPD model was established by smoke exposure combined with Klebsiella pneumoniae infection in model group and POM group.The rats in POM group were treated with POM(0.5 mg/kg,once a day for 1 week).The lung function,lung tissue pathology,the proportion of inflammatory cells in bronchoalveolar lavage fluid(BALF)and the levels of serum inflammatory factors tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6 and IL-13 were observed and detected in each group.AB-PAS staining and immunohistochemistry were used to analyze the proliferation of goblet cells and the secretion of mucin(MUC)5AC and MUC5B in airway epithelium of rats.The expression levels of TNF-α receptor 1(TNFR1),IκB kinase(IKK),phosphorylated IKK(p-IKK)and P65 protein in lung tissue were detected by Western blotting.Results Compared with control group,model group showed significant decreased of tidal volume(TV),minute ventilation(MV),forced expiratory vital capacity(FVC),0.1s forced expiratory volume(FEV0.1)and 0.3 s forced expiratory volume(FEV0.3)(P<0.05),increased of the mean linear intercept(MLI)of the alveoli(P<0.01),decreased of the mean alveolar number(MAN)(P<0.01),increased of the proportion of neutrophils and lymphocytes in BALF sediment(P<0.05),and decreased of the proportion of macrophages in BALF sediment(P<0.01);increased of the levels of serum inflammatory factors TNF-α,IL-1β,IL-13 and IL-6(P<0.05),the proportion of goblet cells in airway epithelium(P<0.01),the secretion of MUC5AC and MUC5B in lung tissue(P<0.01),the content of TNFR1 and the ratio of p-IKK/IKK(P<0.01),the content of P65 in nucleus(P<0.01);and decreased of the content of P65 in cytoplasm(P<0.05).Compared with model group,after one week of POM treatment,POM group showed significant improved of the TV,MV,FVC,FEV0.1,FEV0.3,MLI and MAN of rats(P<0.05);decreased of the proportion of neutrophils and lymphocytes in BALF(P<0.05);increased of the proportion of macrophages(P<0.01);decreased of the levels of serum TNF-α,IL-1β,IL-6 and IL-13(P<0.05),the proportion of goblet cells in airway(P<0.01),the secretion of MUC5AC and MUC5B(P<0.01),and the expression of TNFR1,P-IKK and P65(nucleus)(P<0.05);and increased of the level of P65(cytoplasm)(P<0.01).Conclusions POM can improve airway inflammation and mucus hypersecretion in COPD rats,which may be achieved by inhibiting TNF-α/NF-κB signaling pathway.

Objective To systematically evaluate the influencing factors for pulmonary infection after cardiac sur-gery.Methods Literatures were retrieved from PubMed,Embase,Web of Science,the Cochrane Library,CBM,Wanfang,CNKI and VIP databases.The retrieval time was from the establishment of databases to November 22,2022.Meta-analysis was performed with RevMan 5.4 and Stata 15.0 softwares.Results A total of 20 literatures were included in the analysis.Meta-analysis showed that age(≥65 years),mechanical ventilation time(≥5 days),smoking,acute renal damage,perioperative blood transfusion,operation time(≥240 minutes),secondary thora-cotomy,and oxygenation index(PaO2/FiO2≤300 mmHg)were risk factors for postoperative pulmonary infection.Conclusion The existing evidence shows that all of the above 8 factors are risk factors for pulmonary infection after cardiac surgery,which can provide a theoretical basis for health care workers to prevent and treat infection.

Objective To observe the effectiveness of fluorescence labeling-based assay bundle intervention in the prevention and control of multidrug-resistant organism(MDRO)infection.Methods Patients who were detected MDRO in a hospital from January to December 2022 were selected as the research subjects.MDRO monitoring data and implementation status of prevention and control measures were collected.Fluorescence labeling assay was adopted to monitor the cleaning and disinfection effectiveness of the surrounding object surface of the bed units.Based on the bundled prevention and control measures as well as management mode of the pre-intervention group,the post-intervention group implemented enhanced rectification measures for the problems found by the pre-interven-tion group.Changes in relevant indicators between January-June 2022(before intervention)and July-December 2022(after intervention)were compared.Results There were 136 MDRO-infected patients in the pre-intervention group,208 MDRO strains were detected and 10 healthcare-associated infection(HAI)occurred.There were 128 MDRO-infected patients in the post-intervention group,198 MDRO strains were detected and 9 HAI occurred.Af-ter intervention,the total detection rates of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-re-sistant Acinetobacter baumannii(CRAB),and total MDRO from patients decreased significantly compared to before intervention(all P＜0.05).After intervention,the detection rates of MRSA,carbapenem-resistant Pseudomonas aeruginosa(CRPA),CRAB,and total MDRO from the surrounding object surface were all lower than those before intervention(all P＜0.05).The detection rate of MDRO from surrounding object surface before intervention was 34.52％,which showed a decreased trend after intervention(P＜0.05).The clearance rate of fluorescent labeled markers before intervention was 41.84％,which showed an upward trend after implementing intervention measures(from July to December),and increased to 85.00％at the end of intervention(November-December).The comp-liance rates of issuing isolation medical orders,placing isolation labels,using medical supplies exclusively,and cor-rectly handling medical waste after intervention have all increased compared to before intervention(all P＜0.05).Conclusion Adopting fluorescence labeling-based assay bundle intervention can effectively improve the effectiveness of MDRO infection prevention and control.

ObjectiveTo study the effect and mechanism of Yixintai on mitochondrial fission proteins in the rat model of chronic heart failure. MethodTen of 60 SD rats were randomly selected as the sham operation group， and the remaining 50 rats were subjected to ligation of the left anterior descending coronary artery for the modeling of heart failure post myocardial infarction. The successfully modeled rats were randomized into model， low-， medium-， and high-dose （1.4， 2.8， and 5.6 g·kg^-1， respectively） Yixintai， and trimetazidine （10 mg·kg^-1） groups. The rats were administrated with corresponding doses of drugs by gavage， and the rats in the model group and sham operation group were given an equal volume of normal saline by gavage for 28 consecutive days. Enzyme-linked immunosorbent assay （ELISA） was then employed to measure the levels of amino-terminal pro-B-type natriuretic peptide （NT-pro BNP）， B-type natriuretic peptide （BNP）， and adenosine triphosphate （ATP） in the serum. Color Doppler ultrasound imaging was conducted to examine the cardiac function indicators. Hematoxylin-eosin staining and Masson staining were conducted to observe the pathological changes in the heart， and Image J was used to calculate collagen volume fraction （CVF）. Transmission electron microscopy was employed to observe the ultrastructural changes of myocardial cells. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling （TUNEL） was employed to measure the apoptosis rate of myocardial cells. Western blot was employed to determine the protein levels of mitochondrial fission protein 1 （Fis1） and mitochondrial fission factor （Mff） in the outer mitochondrial membrane of the myocardial tissue. ResultCompared with the sham operation group， the model group showed elevated levels of NT-pro BNP and BNP in the serum， decreased ATP content， left ventricular ejection fraction （LVEF）， and left ventricular fraction shortening （LVFS）， increased left ventricular end-diastolic diameter （LVIDd） and left ventricular end-systolic diameter （LVIDs）， disarrangement of myocardial cells， inflammatory cell infiltration， increased collagen fibers and CVF， damaged myocardium and mitochondria， and increased apoptosis rate of myocardial cells， and up-regulated expression of Fis1 and Mff in the cardiac tissue （P<0.01）. Compared with the model group， different doses of Yixintai and trimetazidine lowered the serum levels of NT-pro BNP and BNP （P<0.05）， increased the ATP content （P<0.05）， increased LVEF and LVFS （P<0.01）， decreased LVIDd and LVIDs （P<0.01）. Moreover， the drugs alleviated the myocardial inflammatory damage and fibrosis， reduced CVF （P<0.01）， repaired the myocardial mitochondrial structure， and decreased the apoptosis rate of myocardial cells （P<0.01）. Medium- and high-dose Yixintai and trimetazidine down-regulated the expression of Fis1 and Mff in the myocardial tissue （P<0.05）. ConclusionYixintai can improve mitochondrial structure， reduce myocardial cell apoptosis， and improve cardiac function by inhibiting the expression of Fis1 and Mff in the myocardial tissue.

Four pyrazines were isolated from the n-butanol fraction of Hypecoum erectum L. by using various chromatographic methods, including MCI gel, ODS, silica gel and semi-preparative HPLC. The structures of the isolated compounds were identified as hyperectpyrazin A (1), 1′S-(6-methylpyrazin-2-yl)-ethane-1′,2′-diol (2), 2-hydroxymethyl-6-methylpyrazin (3) and pyrazine-2-carboxylic acid (4) by spectroscopy methods (1D NMR, 2D NMR, UV, IR, MS, etc.). The absolute configuration of compound 2 was determined by using the Mo₂(OAc)₄ induced CD analysis for the first time. Compound 1 was a new compound, compounds 2-4 were isolated from H. erectum for the first time. Compounds 1-4 were evaluated for their inhibition against acetylcholinesterase and nitric oxide generation induced by lipopolysaccharide-RAW264.7 macrophage cells. At a concentration of 50 μmol·L^-1, compounds 2 and 4 displayed inhibitory effects on acetylcholinesterase with the inhibition rates of 44.40% and 43.99%, respectively.

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 explore the relevant risk factors of H.pylori infection,and provide reference for prevention and treatment of H.pylori in this area,and further provide theoretical basis for the prevention and treatment of gastric cancer.Methods A total of 1200 residents in four districts of Haikou city were investigated by questionnaire and urea 14 C breath test by holistic stratified random sampling to calculate the population infection rate and analyze the risk factors of infection.Results The total infection rate was 32.5％,which was lower than the national H.pylori infection rate.No consumption of fruits and vegetables,no habit of washing hands before meals,and people with gastrointestinal symptoms,are independent risk factors of H.pylori infection.No consumption of pickled products is of great significance to prevent H.pylori infection.Conclusion The prevalence of H.pylori infection in the population of Haikou is lower than the national average,and H.pylori infection is closely related to the poor living habits of residents.

Objective The purpose of this study was to investigate the bacterial communities of biting midges and ticks collected from three sites in the Poyang Lake area,namely,Qunlu Practice Base,Peach Blossom Garden,and Huangtong Animal Husbandry,and whether vectors carry any bacterial pathogens that may cause diseases to humans,to provide scientific basis for prospective pathogen discovery and disease prevention and control. Methods Using a metataxonomics approach in concert with full-length 16S rRNA gene sequencing and operational phylogenetic unit(OPU)analysis,we characterized the species-level microbial community structure of two important vector species,biting midges and ticks,including 33 arthropod samples comprising 3,885 individuals,collected around Poyang Lake. Results A total of 662 OPUs were classified in biting midges,including 195 known species and 373 potentially new species,and 618 OPUs were classified in ticks,including 217 known species and 326 potentially new species.Surprisingly,OPUs with potentially pathogenicity were detected in both arthropod vectors,with 66 known species of biting midges reported to carry potential pathogens,including Asaia lannensis and Rickettsia bellii,compared to 50 in ticks,such as Acinetobacter lwoffii and Staphylococcus sciuri.We found that Proteobacteria was the most dominant group in both midges and ticks.Furthermore,the outcomes demonstrated that the microbiota of midges and ticks tend to be governed by a few highly abundant bacteria.Pantoea sp7 was predominant in biting midges,while Coxiella sp1 was enriched in ticks.Meanwhile,Coxiella spp.,which may be essential for the survival of Haemaphysalis longicornis Neumann,were detected in all tick samples.The identification of dominant species and pathogens of biting midges and ticks in this study serves to broaden our knowledge associated to microbes of arthropod vectors. Conclusion Biting midges and ticks carry large numbers of known and potentially novel bacteria,and carry a wide range of potentially pathogenic bacteria,which may pose a risk of infection to humans and animals.The microbial communities of midges and ticks tend to be dominated by a few highly abundant bacteria.

Objective To develop a portable medical oxygen purity analyzer capable of real-time detection of multi-compo-nent gases in medical oxygen or aviation oxygen to ensure the safety of oxygen consumption.Methods The portable medical oxygen purity analyzer with STM3F103RC as the main controller involved in a management module,an oxygen detection module,a carbon monoxide/chlorine detection module,a flow/carbon dioxide detection module and a dew point detection module as its hardware components,which had its human-machine interface programmed with DGUS supervision,control and data acquisition(SCADA)software and system program developed with C language under Keil MDK environment.The performance verification of the analyzer developed was carried out in terms of oxygen detection error and stability and errors for measuring carbon monoxide,chlorine and carbon dioxide.Results The analyzer showed high precision when used to detect oxygen with high volume fraction,with long-term stability and the absolute error restrained within±0.1％;the erros for measuring carbon monoxide,chlorine and carbon dioxide were all limited within±5％FS to meet the desired requirements.Condusion The portable medical oxygen purity analyzer developed with high precision,stability and portability can be used for detection of medical oxygen and aviation oxygen.[Chinese Medical Equipment Journal,2024,45(3):36-40]