ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

Background Although current evidence suggests a link between outdoor air pollution and depressive symptoms, the effect of solid fuel use (a significant indoor air pollutant) on depressive symptoms in China's rural middle-aged and elderly population remains poorly understood. Objective To explore the association between solid fuel use for cooking and depressive symptoms among middle-aged and elderly people in rural areas of China, and to provide a basis for the prevention and control of depressive symptoms among residents in rural areas. Methods Data were obtained from the 2020 China Family Panel Studies (CFPS), depressive symptoms were assessed using 8-item Center for Epidemiologic Studies Depression Scale (CES-D), and cooking fuel type was self-reported. Subsequently, two-level binary unconditional logistic regression models were fitted to assess the impact of solid fuel use for cooking on depressive symptoms. Results A total of 7991 participants aged 45 years and older [mean age (58.52±9.18) years] were included in the study, with a mean CES-D score of 6.07±4.48 and a mean positive depressive symptoms rate of 34% (40.54% in the solid fuel group and 30.81% in the clean fuel group, χ²=74.40, P<0.001). After controlling for potential confounding covariates, rural middle-aged and elderly residents in the solid fuel group had a higher risk of reporting depressive symptoms than those in the clean fuel group (OR=1.36, 95%CI: 1.20-1.54), an association that was unaffected by participant characteristics and was positive across age and gender groups. Conclusion There is a positive association between solid fuel use for cooking and depressive symptoms in middle-aged and elderly people in rural areas of China. It is recommended that rural areas promote the upgrading of stoves through the installation of ventilation equipment or the switch from solid cooking fuel to clean fuel. This approach is directed toward reducing exposure to household air pollution, alleviating the prevalence of depression among middle-aged and elderly residents in vast rural areas, and enhancing their mental health.

ObjectiveThis study aims to identify cuproptosis-related gene biomarkers in Alzheimer's disease（AD） using bioinformatics and machine learning methods， validate them at the clinical specimen level， and predict potential traditional Chinese medicine（TCM）. MethodsDifferentially expressed genes in the AD group and normal group were obtained using the Gene Expression Omnibus （GEO） database， and intersections were taken with reported cuproptosis-related genes to obtain differentially expressed cuproptosis-related genes. Machine learning methods were applied to identify core differential genes of cuproptosis in AD. Peripheral blood's single nucleated cells from clinical AD patients were collected， and the relative gene expression was clinically verified by real-time polymerase chain reaction（Real-time PCR）. Potential TCM regulating cuproptosis for AD were predicted by COREMINE database. ResultsA total of 12 cuproptosis-related genes were obtained， mainly involved in pathways of tricarboxylic acid cycle， 2-oxocarboxylic acid metabolism， and carbon metabolism. Five core cuproptosis-related genes， dihydrolipoamide dehydrogenase （DLD）， glutaminase （GLS）， pyruvate dehydrogenase E1 subunit beta （PDHB）， full name nuclear factor （erythroid-derived 2）-related factor 2 （NFE2L2）， and dihydrolipoamide branched-chain transacylase E2 （DBT） were finally screened using four machine methods. Thirty cases each of normal and AD patients were collected clinically. Compared with those in the normal group， minimum mental state examination （MMSE） and Montreal cognitive assessment （MoCA） were significantly decreased in the AD group （P<0.01）， Homocysteine（Hcy）， interleukin（IL）-6， C-reactive protein（CRP） ， and β amyloid protein（Aβ） indexes were significantly increased （P<0.01）， and malondialdehyde（MDA） indexes were decreased （P<0.05）. Superoxide dismutase（SOD） levels were significantly decreased （P<0.01）. The mRNA relative expressions of NFE2L2 and DBT were up-regulated （P<0.05）， and those of DLD， GLS， and PDHB were significantly down-regulated （P<0.01）. The TCM regulating cuproptosis-related genes for the treatment of AD were mainly based on the four Qi such as warmth， calmness， and cold， and the five flavors including bitterness， sweetness， and pungency， and it was attributed to the meridians of the liver， spleen， stomach， and kidney， with the efficacy of tonifying Qi， activating blood， eliminating phlegm， and resoling dampness. ConclusionDLD， GLS， NFE2L2， PDHB， and DBT can be used as novel diagnostic molecular markers for AD cuproptosis-related genes， and the corresponding potential therapeutic TCM can provide new ideas for the treatment of AD by TCM.

Pyroptosis is the programmed death of cells accompanied by an inflammatory response and is widely involved in the development of a variety of diseases, such as infectious diseases, cardiovascular diseases, and neurodegeneration. It has been shown that cellular scorching is involved in the pathogenesis of pulmonary arterial hypertension ( PAH) in cardiovascular diseases. Patients with PAH have perivascular inflammatory infiltrates in lungs, pulmonary vasculopathy exists in an extremely inflam-matory microenvironment, and pro-inflammatory factors in cellular scorching drive pulmonary vascular remodelling in PAH patients. This article reviews the role of cellular scorch in the pathogenesis of PAH and the related research on drugs for the treatment of PAH, with the aim of providing new ideas for clinical treatment of PAH.

Aim To discover the potential active compounds and possible mechanisms in rheumatoid arthritis (RA) treatment with Zhi-Huang-Zhi-Tong powder (ZHZTP) by using network pharmacology and in vitro study. Methods The active ingredient targets and disease targets of Zhihuang Zhitong Powder were searched and screened by database; they intersected to get a common target; and the "drug-component-target" relationship network diagram was constructed for GO and KEGG enrichment analysis of the overlapping genes; then the core components were docked with the core targets. Finally, based on the inflammation model of HUVECs in vitro, the efficacy and mechanism of Zhihuang Zhitong powder were verified by MTT method, plate scratch test and Western blot. Results Active compounds involved in RA treatment were screened in the present study, and the top two were ursolic acid and emodin, all playing crucial roles in RA treatment with ZHZTP. Additionally, the key target was AKTA, TNF and IL-6. GO and KEGG enrichment analysis revealed that ZHZTP regulated BP, MF and CC, and also focused on regulating AKTA, TNF and IL-6 signaling pathway. Molecular docking showed that interactions between key active compounds and key targets were stable. In vitro ZHZTP significantly inhibited cell viability and migration of TNF-a-stimulated HUVECs, and the involved mechanism may be associated with PI3K/AKT/m-TOR signaling. Conclusions The present study reveals that the potential active compounds of ZHZTP are ursolic acid and emodin, and moreover, the involved mechanisms of ZHZTP for RA treatment are associated with PI3 K/AKT/m-TOR signaling.

Objective To investigate the expression of CD4+T cell subtypes and related inflammatory factors in patients with neutrophil-predominant frequent acute exacerbation chronic obstructive pulmonary disease(NE-FE-COPD).Methods COPD patients who were treated in the hospital from March 2019 to March 2021 were selected as the research objects.According to different phenotypes,they were divided into the infrequent exacerbator COPD group(IECOPD group,n=11),the eosinophilic dominant frequent acute plus severe COPD group(Eos-FE-COPD group,n=13),and the neutrophil dominant frequent exacerbator COPD group(NE-FE-COPD group,n=15).Patients with normal lung function and smoking history＞10 packs/year were the control group(CTRL group,n=9).Bronchoalveolar lavage fluid(BALF)was collected from each group,and the expression of CD4+T cell subtypes and inflammatory factors were detected by flow cytometry.The correlation between BALF and lung function and the frequency of acute exacerbation was ana-lyzed.CD4+CD28nullT cells and CD4+CD28+T cells were co-cultured with human airway epithelial cells(hAECs)and divided into co-culture group and Control group.The damage of hAECs was observed by immu-nofluorescence staining,and the mRNA and protein expression levels of ZO-1 and occludin were detected by RT-qPCR and Western blot.Results The proportion of CD4+CD28nullT cells and IL-1β level in BALF in the NE-FE-COPD group were higher than those in the CTRL group,the IE-COPD group,and the Eos-FE-COPD group,and the difference was statistically significant(P＜0.05).The proportion of CD4+CD28nullT cells and IL-1βlevel were negatively correlated with lung function(P＜0.05),and positively correlated with acute ex-acerbation frequency(P＜0.05).Compared with the Control group,hAECs tight junctions were damaged in the co-culture group,and mRNA and protein expression levels of ZO-1 and occludin decreased,with statistical significance(P＜0.05).Conclusion CD4+CD28nullT cells and IL-1β may be involved in the occurrence and de-velopment of NE-FE-COPD.

Objective To explore the severity of loneliness among the elderly in communities in Shanghai,and to identify factors associated with social and emotional loneliness respectively.Methods A cross-sectional study was conducted in older adults aged 65 years or above in Pudong New Area,Jing'an District and Huangpu District in Shanghai from Mar to Jun 2021.In Pudong New Area,multi-stage stratified random sampling was conducted based on the age and gender distribution of Shanghai,while in Huangpu District and Jing'an District convenience sampling was conducted.A total of 635 samples were included in the study.Loneliness was assessed using the De Jong Gierveld Loneliness Scale with social and emotional loneliness subscales.Logistic regression analyses were conducted to identify factors associated with social and emotional loneliness.Results Among the 635 participants,only 53 older adults(8.4%)were not lonely.Female(OR=0.46,95%CI:0.31-0.70),higher self-efficacy(OR=0.97,95%CI:0.94-1.00),more objective social support(OR=0.96,95%CI:0.93-0.99)were associated with less severe social loneliness.Meanwhile,higher level of education(secondary education,OR=0.56,95%CI:0.34-0.95;college or above,OR=0.30,95%CI:0.11-0.83)and higher self-efficacy(OR=0.96,95%CI:0.93-0.99)were associated with less severe emotional loneliness,while depression(OR=3.41,95%CI:1.76-6.60)and worse social capital(OR=2.02,95%CI:1.29-3.16)were associated with more severe emotional loneliness.Conclusion Up to 91.6%of the elderly in our study sample were moderately lonely or above.The factors associated with social loneliness include self-efficacy,gender and social support.The factors associated with emotional loneliness are self-efficacy,education level,depression,and social capital.

Objective To explore the role of endothelial cells in angiogenesis and myocardial remodeling in heart failure based on MAPKs pathway mediated by tumor endothelial marker 1(TEM1).Methods Sixty-four mice were equally randomized into four groups:sham operation,myocardial infarction(MI),MI+sh-NC and MI+ sh-TEM1.On the 7th day after MI,the changes of EndMT in the infarct border area were detected by immunofluo-rescence staining,and the cardiac function of mice was evaluated by echocardiography on the 28th day.Mouse aortic endothelial cells(MAECs)were divided into three groups:control,Vector and rTEM1.In addition,MAECs were pretreated with MAPK inhibitor SB203580,and the cells were treated with rTEM1 for 48 h.The changes of EndMT and MAPKs signaling pathways in endothelial cells were evaluated by Western blot.Results In the myocardium at the border of infarction,the level of TEM1-1 increased slightly on the 1st day after MI,reached the peak on the 7th day,and then decreased on the 28th day.Compared with Vector group,the expression of VE-Cadherin protein in the rTEM1 group decreased significantly(P<0.05),and the levels of α-SMA and vimentin,relative migration distance,the number of invading cells,and the number of branching formation increased signifi-cantly(P<0.05).SB203580 reversed these changes of MAECs induced by rTEM1.Compared with the MI group,the co-staining level of CD31+Vimentin+ in the MI+sh-TEM1 group decreased significantly(P<0.01).On the 28th day,the LVEF and LVFS in the MI+sh-TEM1 group were significantly higher than those in MI group(P<0.05).Compared with the MI group,the expressions of p-P38/P38 and p-JNK/JNK in the endothelial cells of the MI+sh-TEM1 group decreased.Conclusion EndMT and angiogenesis induced by TEM1 participate in the pathogenesis of cardiac fibroblasts induced by MI,which may be mechanically related to the activation of MAPKs signaling pathway.

Objective To investigate the prevalence of Echinococcus infections in small rodents around human residential areas in Yushu City, Qinghai Province in 2023, so as to provide insights into precision echinococcosis control. Methods One or two quadrats, each measuring 50 m × 50 m, were randomly assigned in Shanglaxiu Township and Longbao Township, Yushu City, Qinghai Province on June 2023, respectively, and 300 plate-type mouse traps, each measuring 12.0 cm × 6.5 cm, were assigned in each quadrat. Small rodents were captured during the period between 10 : 00 and 18 : 00 each day for 4 days. Then, all captured small rodents were identified and dissected, and liver specimens with suspected Echinococcus infections were subjected to pathological examinations. The Echinococcus cytochrome c oxidase 1 (cox1) gene was amplified using PCR assay, and the sequence of the amplified product was aligned to that was recorded in the GenBank to characterize the parasite species. In addition, a phylogenetic tree of Echinococcus was generated based on the cox1 gene sequence using the neighbor-joining method. Results A total of 236 small rodents were captured in Shanglaxiu and Longbao townships, Yushu City, including 65 Qinghai voles and 51 plateau pikas in Shanglaxiu Township, and 62 Qinghai voles and 58 plateau pikas in Longbao Township, and there was no significant difference in the constituent ratio of small rodents between the two townships (χ² = 0.294, P > 0.05). Seven plateau pikas and 12 Qinghai voles were suspected to be infected with Echinococcus by dissection, and pathological examinations showed unclear structure of hepatic lobules and disordered hepatocyte arrangement in livers of small rodents suspected of Echinococcus infections. PCR assay identified E. shiquicus DNA in 7 Qinghai voles, which were all captured from Shanglaxiu Township. Phylogenetic analysis showed that the cox1 gene sequence of Echinococcus in small rodents was highly homologous to the E. shiquicus cox1 gene sequence reported previously. Conclusion Plateau pika and Qinghai vole were predominant small rodents around human residential areas in Yushu City, Qinghai Province in 2023, and E. shiquicus infection was detected in Qinghai voles.

The clock gene Rev-erbα, also known as nuclear receptor subfamily 1 group D member 1 (Nr1d1), is a crucial regulatory factor in organisms. It exhibits circadian rhythmic expression in metabolically active tissues such as skeletal muscles, heart, liver, and adipose tissue, responding to various environmental stimuli. Rev-erbα plays a significant role in regulating circadian rhythms, metabolic homeostasis, and other physiological processes, earning its designation as an “integrator” of the circadian system and metabolism. Rev-erbα establishes complex connections with other clock genes through the transcriptional-translational feedback loop (TTFL), which is important for the rhythmic output of biological clock system and for the relative stability of phases and cycles. Mitochondrial biogenesis is a physiological process initiated by cells to maintain energy homeostasis by using existing mitochondria as a template for self-growth and division. As the “energy factory” of organism, disruptions in mitochondrial biogenesis are closely associated with the development of various diseases. Studies have shown that not only the factors involved in mitochondrial biogenesis have circadian oscillations, but also the morphology, dynamics and energy metabolism of mitochondria themselves have cyclic fluctuations throughout the day, suggesting that mitochondrial biogenesis is regulated by the biological clock system, in which the clock gene Rev-erbα plays a key role, it drives mitochondrial biogenesis and synergistically regulates autophagy to normalize a number of physiological processes in the body. Rev-erbα is sensitive to both internal and external environmental changes, and disruptions in circadian rhythms, metabolic diseases, and aging are significant inducers of changes in Rev-erbα expression, and its concomitant inflammation and oxidative stress may be an intrinsic mechanism for inhibiting mitochondrial biogenesis. Therefore, the enhancement of mitochondrial biogenesis by regulating the Rev-erbα activity status may be an important way to improve the pathology and promote the health of organism. Exercise, as a commonly accepted non-pharmacological tool, plays an important role in enhancing mitochondrial biogenesis and promoting health. It has been found that there is a close relationship between exercise and Rev-erbα. On the one hand, exercise stimulation directly affects the expression of Rev-erbα, especially high-intensity and long-term regular exercise; on the other hand, Rev-erbα achieves indirect regulation of exercise capacity by mediating processes such as skeletal muscle mitochondrial biogenesis and autophagy, muscle mass maintenance, energy metabolism and skeletal muscle regeneration. Based on the above findings, it is hypothesized that Rev-erbα may serve as a key bridge between exercise and mitochondrial biogenesis. Exercise enhances the transcriptional response of Rev-erbα in the nucleus, upregulates the expression of Rev-erbα protein in cytoplasm, activates the AMP-activated proteinkinase (AMPK)/ silent information regulator 1 (SIRT1)/peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) pathway, regulates Ca²⁺ flux and downstream signaling molecules; meanwhile, exercise can upregulate antioxidant gene expression and alleviate oxidative stress through Rev-erbα, which ultimately enhances the function of mitochondria, and promotes mitochondrial biogenesis. In conclusion, the clock gene Rev-erbα emerges as a crucial target for exercise-induced enhancement of mitochondrial biogenesis. In this paper, the biological characteristics ofRev-erbα, the role of Rev-erbα in regulating mitochondrial biogenesis and the factors that may influence it, the interaction between exercise and Rev-erbα, and the potential mechanism of exercise-induced mitochondrial biogenesis via Rev-erbα are sorted out and discussed, which can provide theoretical references to the mechanism of exercise-promoted mitochondrial biogenesis.