OBJECTIVE To analyze the chemical constituents of the active parts of Piper wallichii. METHODS The petroleum ether-extract fraction was prepared from the methanol extract of P. wallichii. Separation and purification were performed using semi-preparative high-performance liquid chromatography. The structures of the compounds were identified by nuclear magnetic resonance spectroscopy. RESULTS Nineteen compounds were isolated from the petroleum ether-extract fraction from the methanol extract of P. wallichii， identified as 3-acetoxybenzyl benzoate （1）， 2-acetoxybenzyl benzoate （2）， 2-methoxybenzyl benzoate （3）， 3-methoxybenzyl benzoate （4）， 4-hydroxy-3-methoxybenzyl benzoate （5）， 3-hydroxybenzyl benzoate（6）， benzyl benzoate （7）， ganschisandrine （8）， lancifolin A （9）， （7R，8R，3′R）-7-acetoxy-3′，4′-dimethoxy-3，4-methylenedioxy-6′-oxo- Δ1′，4′，8′-8.3′-lignan （10）， （7S，8R，3′S）-Δ8′-3′，6′-dihydro-3′-methoxy-3，4-methylenedioxy-6′-oxo-8.3′，7.O.4′-lignan （11）， （7R， 8R，3′S）-Δ8′-3′，6′-dihydro-3′-methoxy-3，4-methylenedioxy-6′-oxo-8.3′，7.O.4′-lignan （12）， isodihydrofutoquinol A （13）， licarin A （14）， licarin B （15）， 2-（2′，5′-dimethoxyphenyl）-3，4- dimethyl-5-（3″，4″-dimethoxyphenyl）- tetrahydrofuran （16）， galgravin （17）， velutin （18）， and piyunin A （19）. CONCLUSIONS Compound 1 is a new benzyl benzoate compound. Compounds 3-5， 8 and 9 are isolated from the Piper genus for the first time， while compounds 2， 6， 10-13 and 15-19 are isolated from P. wallichii for the first time.

Objective: To investigate the Alzheimer's disease (AD) influencing factors among the elderly, so as to provide a basis for early prevention and intervention. Methods: From March to June 2024, participants aged 60 years and above from a sub-district in Haishu District, Ningbo City, Zhejiang Province were selected using a convenience sampling method. Data on demographics, lifestyle, and health status were collected through questionnaire surveys. Depressive symptoms were evaluated using the short-form Geriatric Depression Scale. The Chinese Mini-Mental State Examination (MMSE) was used for the initial screening of AD, and individuals who screened positive were further diagnosed by psychiatrists. Factors affecting AD among the elderly were analyzed using a multivariable logistic regression model. Results: A total of 3 644 individuals were surveyed, comprising 1 526 males (41.88%) and 2 118 females (58.12%). The mean age was (71.85±7.44) years. AD was detected in 200 cases, with a detection rate of 5.49%. Multivariable logistic regression analysis showed that individuals aged ≥65 years (65-<70 years, OR=3.012, 95%CI: 1.007-9.012; 70-<75 years, OR=3.131, 95%CI: 1.059-9.260; 75-<80 years, OR=5.779, 95%CI: 1.989-16.784; ≥80 years, OR=16.810, 95%CI: 5.926-47.685), those who were unmarried, divorced, or widowed (OR=1.973, 95%CI: 1.383-2.815), those with hearing loss (OR=1.573, 95%CI: 1.128-2.193), those with diabetes mellitus (OR=1.958, 95%CI: 1.362-2.814), and those with depressive symptoms (OR=4.143, 95%CI: 2.997-5.728) had a higher risk of AD. Conversely, individuals with an educational level of primary school or above (primary school, OR=0.579, 95%CI: 0.401-0.835; junior high school or above, OR=0.438, 95%CI: 0.259-0.741), and those who engaged in regular physical exercise (OR=0.414, 95%CI: 0.264-0.649) had a lower risk of AD. Conclusions The detection rate of AD was relatively high among the elderly in Haishu District. AD among the elderly was related to age, educational level, marital status, physical exercise, hearing loss, diabetes mellitus, and depressive symptoms.

The continuous emergence of SARS-CoV-2 variants as well as other potential future coronavirus has challenged the effectiveness of current COVID-19 vaccines. Therefore, there remains a need for alternative antivirals that target processes less susceptible to mutations, such as the formation of six-helix bundle (6-HB) during the viral fusion step of host cell entry. In this study, a novel high-throughput screening (HTS) assay employing a yeast-two-hybrid (Y2H) system was established to identify inhibitors of HR1/HR2 interaction. The compound IMB-9C, which achieved single-digit micromolar inhibition of SARS-CoV-2 and its Omicron variants with low cytotoxicity, was selected. IMB-9C effectively blocks the HR1/HR2 interaction in vitro and inhibits SARS-CoV-2-S-mediated cell-cell fusion. It binds to both HR1 and HR2 through non-covalent interaction and influences the secondary structure of HR1/HR2 complex. In addition, virtual docking and site-mutagenesis results suggest that amino acid residues A930, I931, K933, T941, and L945 are critical for IMB-9C binding to HR1. Collectively, in this study, we have developed a novel screening method for HR1/HR2 interaction inhibitors and identified IMB-9C as a potential antiviral small molecule against COVID-19 and its variants.

Recently, diffusion models have emerged as a promising paradigm for molecular design and optimization. However, most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geometries, with limited research on molecular sequence diffusion models. The International Union of Pure and Applied Chemistry (IUPAC) names are more akin to chemical natural language than the Simplified Molecular Input Line Entry System (SMILES) for organic compounds. In this work, we apply an IUPAC-guided conditional diffusion model to facilitate molecular editing from chemical natural language to chemical language (SMILES) and explore whether the pre-trained generative performance of diffusion models can be transferred to chemical natural language. We propose DiffIUPAC, a controllable molecular editing diffusion model that converts IUPAC names to SMILES strings. Evaluation results demonstrate that our model outperforms existing methods and successfully captures the semantic rules of both chemical languages. Chemical space and scaffold analysis show that the model can generate similar compounds with diverse scaffolds within the specified constraints. Additionally, to illustrate the model's applicability in drug design, we conducted case studies in functional group editing, analogue design and linker design.

Objective To investigate the effect and mechanism of melatonin on the anoikis of melanoma cells.Methods The drug concentration of melatonin inhibiting melanoma cell line B16-F10 was optimized based on the effect on CCK-8 assay.An anti-anoikis of melanoma cell model was developed and divided it into four groups:The blank control group,the TrkB activator group,the melatonin group and the melatonin+TrkB activator group.Calce-in AM/EthD-1 fluorescence double staining was used to detect the anoikis of melanoma cells.Reactive oxygen spe-cies were detected using the fluorescent probe DCFH-DA.Western blot was used to detect the expression of Nrf2 protein and TrkB protein in each group.Results Melatonin significantly inhibited the proliferation of melanoma cells in a time-and dose-dependent manner with IC50 of 1×10-7 μmol/L.Its inhibitory effect was found to be related to in-duction of anoikis of melanoma cells.Melatonin could upregulate the generation of cellular reactive oxygen species(P<0.05),while addition of TrkB activator antagonized this effect.Melatonin could reduce the expression of Nrf2 protein and TrkB protein in melanoma cells(P<0.05),and the addition of TrkB activator could inhibite the effect of melatonin on the expression of Nrf2 protein and TrkB protein(P<0.05).Conclusions Melatonin can inhibit the pro-liferation of melanoma cell line B16-F10 through the mechanism of inducing anoikis.

Objective To explore the role of Schlafen4(SLFN4)in acute pneumonia induced by hypervirulent Klebsiella pneumoniae(hvKp)via intratracheal aerosolization.Methods Differential expression gene Slfn4 was identified after infection with hvKp based on RNA sequencing(RNA-seq)and single-cell RNA sequencing(scRNA-seq)data before Slfn4-/-mice were obtained via CRISPR/Cas gene editing technology.Slfn4-/-mice and wild mice were challenged via intratracheal aerosolization.Mortality and weight changes were recorded for 14 d,while pathological changes and expression levels of interleukin-6(IL-6),IL-17A,IL-1β,and tumor necrosis factor-α(TNF-α)were detected at 48 h post-infection.Results SLFN4 expression was significantly increased in wild mice after infection with hvKp.Survival was significantly increased,and weight loss was mitigated before gradual recovery in Slfn4-/-mice after infection.The knockout of SLFN4 attenuated alveolar wall thickening,diminished neutrophil infiltration,and suppressed pro-inflammatory cytokine production(IL-6,IL-17A,IL-1β,TNF-α)in the lung at 48 h post-infection.Conclusion The deletion of SLFN4 may suppress the expression of specific pro-inflammatory cytokines and attenuate neutrophil over-recruitment in the lung,thereby alleviating pneumonia in mice after hvKp infection.

Objective To explore the biological functions of pyroptosis-related genes in pneumonic plague using bioinformatics methods,and to evaluate their potential applicability as diagnostic markers.Methods The pneumonic plague-related dataset GSE220123 was retrieved from the Gene Expression Omnibus(GEO)database and screened for differentially expressed pyroptosis-related genes(DE-PRGs).The functions of DE-PRGs were studied via Gene Ontology(GO),Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses,and immune infiltration analysis.The hub genes were identified via protein-protein interaction(PPI)network analysis,and further screened for key genes with sustained high expression characteristics based on differential expression analysis.The relative expression levels of the key genes were verified using the reverse transcription real-time quantitative PCR(qPCR)method.Results A total of 17 DE-PRGs were screened,and PPI network analysis revealed 7 Hub genes.Among them,Casp4 continued to be up-regulated during the course of pneumonic plague.The results of reverse transcription qPCR were consistent with the those of bioinformatic analyses.Conclusion DE-PRGs play a crucial role in the immune response of pneumonic plague,especially Casp4,which has significant applications as a diagnostic biomarker and potential therapeutic target for pneumonic plague.

Objective : To investigate the drug resistance and pathogenicity of six clinical isolates of Klebsiella pneu- moniae (Kp) ，and to provide a basis for prevention and treatment of Kp infection． Methods : The six strains from different hospitals were isolated ，cultured ，and identified by species-specific gene khe． Their whole genome se- quences (WGS) were obtained using next-generation sequencing technology (NGS) ．Based on the WGS，the cap- sular serotypes，sequence types (ST) and drug-resistance genes of six strains were identified．The capsular sero- type genes and virulence genes were validated or identified using PCR. Broth microdilution tests were conducted to validate their drug susceptibility，and mice were challenged with Kp aerosols by MicroSprayer aerosolizer to evaluate their pathogenicity. Results : The six strains were all serotype K2 but belonged to four ST types ( ST14 ，ST65， ST700，and ST86) ，and collectively carried six virulence genes and 23 drug-resistance genes．All the six strains were resistant to ampicillin，but only one strain was multidrug-resistant．Four strains exhibited high mucoid charac- teristics．Five strains could cause mortality in mice，which were preliminary identified as high virulence strains. Conclusion For the six Kp clinical isolates from different sources，only one strain named NY 13294 is both multi- drug-resistant and highly virulent，and other four highly virulent strains are resistant to one or two types of antibiot- ics.

Objective To establish two golden hamster models infected with hypervirulent Klebsiella pneumoniae via aerosolized intratracheal(i.t.)and intranasal(i.n.)inoculation,and compare their properties.Methods Golden hamsters of 4 to 5 weeks old were exposed to K.pneumoniae NTUH-K2044 via i.t.route and i.n.route respectively.The survival of these golden hamsters was observed and recorded within 14 days of infection before the 50%lethal dose(LD50),survival rate,bacterial respiratory deposition rate,lung bacterial load and histopathology of the infected golden hamsters in the two groups were detected.Results The LD50 of the i.t.route(3×104 CFU)was lower than that of the i.n.route(7×105 CFU)in golden hamsters.After 4×106 CFU NTUH-K2044 infection,the golden hamsters in the i.t.group had 96.46%of the bacteria deposited and colonized in the lung,developed lobar pneumonia and died without exception within 4 days of infection,while those in the i.n.group had 95.62%of the bacteria deposited in the mouth and nose initially before the bacteria moved down to the trachea for colonization and were cleared out gradually.This group mainly acquired bronchopneumonia with relatively mild lung lesions,with a 14-day survival rate of 70%.Conclusion Inoculation routes can make a difference to the disease type of respiratory tract infections in animal models.The i.t.route mainly causes lobar pneumonia with severe lung lesions,while the i.n.route leads to bronchopneumonia with mild lung lesions.The two animal models established above may be utilized for pathogenesis investigation and treatment efficacy evaluation of Klebsiella pneumoniae.

Objective To establish an inhalation infection pneumonia model of C57BL/6J mice with highly virulent and multi-drug resistant Pseudomonas aeruginosa(PA)strain F291007,and to study the microbiological,pathological and immunological characteristics of this model.Methods The strain F291007 was isolated and identified before the bacterial suspension was administered to the mice via aerosolized intratracheal inoculation to establish the pneumonia infection model.In the course of infection,the conditions and survival of the mice were observed,and the bacterial loads,the histopathological states and the cytokine expression levels in the major organs were detected.Finally,three key cytokines were blocked to observe the survival of mice.Results The strain F291007 was isolated and identified.After lethal dose infection,all the mice died within 24 h.After sub-lethal dose infection,a large number of immune cells in the body were capable of phagocytosis and killing of invading pathogens,which was manifested as rapid clearance of bacteria in lungs and the exponential decrease of bacterial load with the passage of time.The pathological changes in lungs were most severe at 1 to 3 days but gradually recovered.After infection,interleukin-6(IL-6),IL-17A and tumor necrosis factor-α(TNF-α)in alveolar lavage fluid and serum were significantly increased at 1 to 3 days.After blocking of these three cytokines with specific antibodies,the survival rates of infected mice decreased significantly.Conclusion A mouse model of gradually-recovered pneumonia infection caused by PA inhalation has been established,suggesting that the first one to three days are critical to immune response after infection through multiple indicators.This mouse model can be used for research on the pathogenesis,immunoregulation and treatment evaluation of highly virulent and multi-drug resistant PA inhalation pneumonia infection.