Two-dimensional nuclear magnetic resonance (2D NMR) is a widely used technique for structural analysis of small molecular compounds. It can obtain information about the hydrogen-hydrogen correlation, hydrogen-carbon single bond correlation, hydrogen-carbon remote correlation, and hydrogen-hydrogen spatial arrangement of compounds. Thus, 2D NMR has an irreplaceable role in the structure elucidation of small molecular products. However, the sample amount of trace components in phytochemical research is very low, and the traditional sampling method (uniform sampling) has problems of poor spectral quality and too long measure time. Increasing the number of scans results in several hours of the acquisition time for a single two-dimensional spectrum, which in turn causes strain on the NMR machine. The non-uniform sampling (NUS) technique can shorten the acquisition time to a large extent and not affect the quality of 2D NMR data, which greatly improves the efficiency of 2D NMR acquisition. In this paper, fuziline, a small molecular compound in the lateral roots of Aconitum carmichaelii was selected as the research object. Its ¹H-¹³C HSQC, ¹H-¹H COSY, HMBC, and NOESY spectra were acquired by US and NUS methods, respectively. By comparing the integral values of NMR signals of three chemical groups in fuziline, it is confirmed that the NUS technique has the advantages of improving the quality of 2D NMR spectra and shortening the acquisition time in structure elucidation of small molecule compounds. In HMBC spectrum, it was further confirmed that NUS technology can improve the quality of the 2D spectra and the signal resolution. This indicates that NUS technology can improve the efficiency and reliability of the structure elucidation of small molecule compounds.

Objective To establish a model of indirectly induced respiratory tract infection with influenza A subtypes H1N1 and H3N2 in animals,to screen influenza virus hosts,and to provide theoretical support for the clinical control of influenza viruses.Methods Fifty BALB/c mice and 50 Hartley guinea pigs were randomly divided into five groups(10 animals/group for each species):normal control group,virus infects 1 group,virus infects 2 group,close transmission 1 group,and close transmission 2 group.Mice and guinea pigs in virus infects 1 and 2 groups were administered influenza A(H1N1)and influenza A(H3N2)viruses via nasal drip.For both virus infects 1 and 2 groups,animals were housed together with those in the close transmission group at a 1∶1 ratio on the following day.On day 7,the lung function,viral titer and viral load of the nasal tissue,trachea,and lung tissue of each group were measured,and pathological changes of the trachea and lung tissue of animals in the close transmission group were evaluated.Results In mice,the viral titers and viral loads of nasal,tracheal,and lung tissues of virus infects 1 and 2 and the closely transmitted groups 1 and 2 were significantly higher(P＜0.01),pathological scores of the trachea and lung tissues were significantly higher(P＜0.01),and the FVC and FEV20 of virus infects l and 2 groups were significantly lower(P＜0.01)than those in the normal control group.The nasal tissue,trachea and lung tissues of guinea pigs in virus infects 1 and 2 groups and close transmission groups 1 and 2 showed significantly higher viral titers and viral loads(P＜0.01),significantly higher trachea and lung histopathological scores(P＜0.01),and significantly lower FVC and FEV200(P＜0.01)than those of the normal control group.Conclusions In this study,influenza A subtypes H1N1 and H3N2 were used to indirectly induce respiratory tract infections in mice and guinea pigs for analyses of animal lung function,respiratory viral titers,viral load,and pathology.The animal models of the indirect transmission of influenza viruses in the respiratory tract had certain limitations;for example,influenza viruses were transmitted less efficiently among mice than among guinea pigs.The guinea pig model was stable.These findings confirm that guinea pigs are suitable hosts for efficient virus replication and transmission.

Objective:To systematically evaluate studies validating the performance of the Global Leadership Initiative on Malnutrition (GLIM) in diagnosing malnutrition.Methods:Seven Chinese and English databases including Embase, Web of Science (WOS), PubMed, CINAHL, Cochrane Library, SinoMed, CNKI, Wanfang Data, and VIP Database were searched for articles on the validation of GLIM criteria published between September 2018 and September 2024. Two researchers independently performed literature screening and data extraction. The concurrent and predictive validity of the criteria was analyzed.Results:A total of 136 papers were included for analysis. The GLIM criteria for diagnosing malnutrition had a sensitivity of 77%, a specificity of 87%, and an area under the curve (AUC) of 0.90. Malnutrition diagnosed by the GLIM criteria predicted prolonged hospital and intensive care unit (ICU) stays, increased readmission and complication rates (both overall and infectious), reduced survivals (median, overall, and disease-free), and increased in-hospital and follow-up mortalities. Both moderate and severe malnutrition predicted decreased overall survival. However, only three studies analyzed the impact of nutritional therapy on the clinical outcomes of malnourished patients.Conclusions:The GLIM criteria accurately differentiate malnutrition and are a valid predictive tool of clinical outcomes. However, the validity criteria in these validation studies were questionable, along with high methodological heterogeneity. Furthermore, there is a lack of studies validating the role of nutritional therapy in improving the clinical outcomes of malnourished patients.

Objective:To describe the prevalence of non-alcoholic fatty liver disease (NAFLD) in people living with HIV in Taizhou, Zhejiang Province, and identify the factors associated with NAFLD in this population.Methods:A cross-sectional survey was conducted from 2021 to 2023. Based on the routine follow-up management of people living with HIV, liver ultrasound examination, physical examination and laboratory test were conducted to collect the information about the diagnosis of NAFLD and biochemical indicators in this population. Logistic regression model was used to identify the factors associated with the prevalence of NAFLD.Results:In the 2 550 study participants, the prevalence of NAFLD was 21.5% (548/2 550), abnormal liver function was found in 23.7% (604/2 550) of the study participants, and liver fibrosis was found in 45.2% (1 152/2 550) of the study participants. Multivariable logistic regression analyses showed that being women (a OR=0.55, 95% CI: 0.42-0.73), being overweight or obese (a OR=3.22, 95% CI: 2.59-4.01), having diabetes (a OR=3.37, 95% CI: 2.15-5.29), having dyslipidemia (a OR=2.96, 95% CI: 2.25-3.89), CD4 + T lymphocyte (CD4) counts <200 cells/μl (a OR=0.61, 95% CI: 0.42-0.88), and receiving Efavirenz (EFV) + Lamivudine (3TC) + Zidovudine (AZT) for antiretroviral therapy (ART)(a OR=1.52, 95% CI: 1.17-1.98) were associated with NAFLD. NAFLD was positively associated with abnormal liver function (a OR=2.01, 95% CI: 1.60-2.52) and inversely associated with liver fibrosis (a OR=0.76, 95% CI: 0.59-0.98). The 45-59 age group (a OR=7.05, 95% CI: 5.65-8.80), CD4 counts <200 cells/μl (a OR=1.45, 95% CI: 1.06-1.97) and receiving Nevirapine (NVP)+3TC+AZT of ART (a OR=1.87,95% CI: 1.44-2.43) were the main factors associated with liver fibrosis. Conclusions:The prevalence of NAFLD in people living with HIV Taizhou was more than 20.0%, with a significant proportion of them having abnormal liver function and liver fibrosis. Being overweight or obese, suffering from diabetes, having dyslipidemia, low CD4 counts, and receiving specific ART were associated with NAFLD. NAFLD, CD4 counts and specific ART were the main factors associated with abnormal liver function and liver fibrosis.

Objective:To analyze the epidemiological characteristics of respiratory syncytial virus (RSV) infections in hospitalized children under five years of age with acute respiratory infections in Qingdao, China, from 2023 to 2025.Methods:This cross-sectional study enrolled children under five years hospitalized with acute respiratory infections between May 1, 2023, and June 30, 2025. Nucleic acid testing was performed for six respiratory pathogens. Participants were stratified into seven age groups: 0 to 28 days, 29 days to <6 months, 6 to <12 months, 1 to <2 years, 2 to <3 years, 3 to <4 years, and 4 to <5 years. Intergroup differences were analyzed using Chi-square tests, with Bonferroni correction (adjusted α=0.016 7) for peak rate comparisons across three epidemic seasons. Results:Among 16 613 children, RSV was detected in 3 280 cases (19.74%), representing the highest pathogen detection rate. Infants under one year accounted for 56.37% (1 849/3 280) of RSV-positive cases, with significantly higher positivity rates in the 0-28 days [25.22% (286/1 134)], 29 days to <6 months [26.66% (1 072/4 021)], and 6 to <12 months [24.92% (491/1 970)] groups compared to other age groups ( χ2=314.20, P<0.001). Co-infections occurred in 13.66% (448/3 280) of RSV-positive cases, primarily with rhinovirus (6.13%, 201/ 3 280), followed by adenovirus and Mycoplasma pneumoniae (3.35% each, 110/3 280). Epidemiological surveillance revealed an off-season outbreak from May to July 2023 (duration ≥14 weeks, peak positivity rate 71.15%), while both 2024 (20 weeks, peak 52.55%) and 2025 (24 weeks, peak 46.49%) exhibited typical winter-spring seasonal patterns. The 2023 peak rate significantly exceeded those of subsequent years (all pairwise P<0.016 7). Conclusion:RSV is the predominant pathogen among hospitalized children under five years with acute respiratory infections in Qingdao, with infants under one year representing the highest-risk population. The epidemiological pattern demonstrates a transition from post-pandemic off-season outbreaks to prolonged winter-spring epidemics, highlighting the need for continued surveillance and targeted prevention strategies.

Objective:To describe the prevalence of non-alcoholic fatty liver disease (NAFLD) in people living with HIV in Taizhou, Zhejiang Province, and identify the factors associated with NAFLD in this population.Methods:A cross-sectional survey was conducted from 2021 to 2023. Based on the routine follow-up management of people living with HIV, liver ultrasound examination, physical examination and laboratory test were conducted to collect the information about the diagnosis of NAFLD and biochemical indicators in this population. Logistic regression model was used to identify the factors associated with the prevalence of NAFLD.Results:In the 2 550 study participants, the prevalence of NAFLD was 21.5% (548/2 550), abnormal liver function was found in 23.7% (604/2 550) of the study participants, and liver fibrosis was found in 45.2% (1 152/2 550) of the study participants. Multivariable logistic regression analyses showed that being women (a OR=0.55, 95% CI: 0.42-0.73), being overweight or obese (a OR=3.22, 95% CI: 2.59-4.01), having diabetes (a OR=3.37, 95% CI: 2.15-5.29), having dyslipidemia (a OR=2.96, 95% CI: 2.25-3.89), CD4 + T lymphocyte (CD4) counts <200 cells/μl (a OR=0.61, 95% CI: 0.42-0.88), and receiving Efavirenz (EFV) + Lamivudine (3TC) + Zidovudine (AZT) for antiretroviral therapy (ART)(a OR=1.52, 95% CI: 1.17-1.98) were associated with NAFLD. NAFLD was positively associated with abnormal liver function (a OR=2.01, 95% CI: 1.60-2.52) and inversely associated with liver fibrosis (a OR=0.76, 95% CI: 0.59-0.98). The 45-59 age group (a OR=7.05, 95% CI: 5.65-8.80), CD4 counts <200 cells/μl (a OR=1.45, 95% CI: 1.06-1.97) and receiving Nevirapine (NVP)+3TC+AZT of ART (a OR=1.87,95% CI: 1.44-2.43) were the main factors associated with liver fibrosis. Conclusions:The prevalence of NAFLD in people living with HIV Taizhou was more than 20.0%, with a significant proportion of them having abnormal liver function and liver fibrosis. Being overweight or obese, suffering from diabetes, having dyslipidemia, low CD4 counts, and receiving specific ART were associated with NAFLD. NAFLD, CD4 counts and specific ART were the main factors associated with abnormal liver function and liver fibrosis.

Objective To establish a model of indirectly induced respiratory tract infection with influenza A subtypes H1N1 and H3N2 in animals,to screen influenza virus hosts,and to provide theoretical support for the clinical control of influenza viruses.Methods Fifty BALB/c mice and 50 Hartley guinea pigs were randomly divided into five groups(10 animals/group for each species):normal control group,virus infects 1 group,virus infects 2 group,close transmission 1 group,and close transmission 2 group.Mice and guinea pigs in virus infects 1 and 2 groups were administered influenza A(H1N1)and influenza A(H3N2)viruses via nasal drip.For both virus infects 1 and 2 groups,animals were housed together with those in the close transmission group at a 1∶1 ratio on the following day.On day 7,the lung function,viral titer and viral load of the nasal tissue,trachea,and lung tissue of each group were measured,and pathological changes of the trachea and lung tissue of animals in the close transmission group were evaluated.Results In mice,the viral titers and viral loads of nasal,tracheal,and lung tissues of virus infects 1 and 2 and the closely transmitted groups 1 and 2 were significantly higher(P＜0.01),pathological scores of the trachea and lung tissues were significantly higher(P＜0.01),and the FVC and FEV20 of virus infects l and 2 groups were significantly lower(P＜0.01)than those in the normal control group.The nasal tissue,trachea and lung tissues of guinea pigs in virus infects 1 and 2 groups and close transmission groups 1 and 2 showed significantly higher viral titers and viral loads(P＜0.01),significantly higher trachea and lung histopathological scores(P＜0.01),and significantly lower FVC and FEV200(P＜0.01)than those of the normal control group.Conclusions In this study,influenza A subtypes H1N1 and H3N2 were used to indirectly induce respiratory tract infections in mice and guinea pigs for analyses of animal lung function,respiratory viral titers,viral load,and pathology.The animal models of the indirect transmission of influenza viruses in the respiratory tract had certain limitations;for example,influenza viruses were transmitted less efficiently among mice than among guinea pigs.The guinea pig model was stable.These findings confirm that guinea pigs are suitable hosts for efficient virus replication and transmission.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

Objective:To analyze the efficacy of transjugular intrahepatic portosystemic shunt (TIPS) combined with main splenic artery embolization in the treatment of patients with portal hypertension upper gastrointestinal bleeding complicated with extensive portal vein thrombosis (PVT).Methods:This study was a prospective, single-center, open-label, single-arm clinical trial. In the first phase, 81 patients with portal hypertension upper gastrointestinal bleeding who were admitted to Beijing Shijitan Hospital, Capital Medical University from January 2018 to December 2018 were consecutively enrolled, including 57 males and 24 females, with the age of (51.3±10.4) years. During TIPS surgery, the pressure of the portal vein before and after the balloon blocking the splenic artery was measured to clarify the contribution of the splenic artery to portal hypertension. In the second stage, from January 2019 to December 2022, 104 patients with portal hypertension upper gastrointestinal bleeding complicated with extensive PVT were re-enrolled, including 71 males and 33 females, with the age of (50.9±12.5) years. TIPS combined with main splenic artery embolization was performed, and portal vein pressure was measured before and after embolization. Follow up on the postoperative esophageal and gastric varices of the patients in the second stage.Results:The portal vein pressures before and after the first stage of balloon occlusion of the splenic artery were (35.2±8.4) mmHg (1 mmHg=0.133 kPa) and (24.2±6.3) mmHg, respectively. The pressure after occlusion was lower than that before occlusion, and the difference was statistically significant ( t=10.54, P<0.001). The portal vein pressures before and after the second stage embolization were (36.1±9.5) mmHg and (21.1±4.7) mmHg respectively. The pressure after embolization was lower than that before embolization, and the difference was statistically significant ( t=13.47, P<0.001). In the second stage, among the 104 patients, the proportion of those whose varicose veins disappeared or improved 6 months after the operation was 43.3%(45/104) and 51.0%(53/104), respectively. There were no patients with aggravation or rebleeding due to rupture. One year later, 8 patients (7.7%) had aggravated or ruptured esophageal and gastric varices with bleeding. Two years later, 12 patients (11.5%) had aggravated or bleeding. Conclusion:TIPS combined with main splenic artery embolization can effectively reduce the portal vein pressure in patients with portal hypertension upper gastrointestinal bleeding complicated with extensive PVT, improve the degree of esophageal and gastric varices, and reduce the risk of gastrointestinal bleeding.