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.

ObjectiveTo study the regulatory effect of the partial sequence within the 3’ untranslated region （3’UTR） of slit guidance ligand 1 （Slit1） （Slit1-3’UTR） on the fibrotic phenotypes of cardiac fibroblasts （CFs） and its potential mechanism. MethodsThe adenovirus vector was used to overexpress the 1526nt sequence of Slit1-3’UTR in ICR neonatal mouse CFs （mCFs）. The expression of fibrosis-related genes in mCFs， such as collagen type 1 alpha1（COL1A1）， collagen type 3 alpha3 （COL3A1） and alpha smooth muscle actin （α-SMA） were detected by Western blot assay. The effect of Slit1-3’UTR 1526nt on the proliferation and migration of mCFs was assessed by EdU staining and Trans-well assays. Angiotensin Ⅱ （Ang Ⅱ） was used to treat mCFs， and the impact of Slit1-3’UTR 1526nt on the fibrotic phenotypes of Ang Ⅱ-induced mCFs was evaluated. After overexpression of Slit1-3’UTR 1526nt， miR-34a-5p mimic was transfected into mCFs， followed by actinomycin D treatment to detect the mRNA stability of Slit1-3’UTR 1526nt， and the levels of miR-34a-5p and its target gene SIRT1（si-SIRT1） in mCFs were determined. The effects of miR-34a-5p and small interfering RNA targeting SIRT1 on the Slit1-3’UTR 1526nt-mediated regulation of fibrotic phenotypes were also determined. ResultsAdenovirus-mediated overexpression of Slit 1-3’UTR 1526nt was achieved in mCFs. Overexpression of Slit 1-3’UTR 1526nt markedly inhibited the expression of the fibrosis-related genes， proliferation and migration of mCFs and fibrotic phenotypes of Ang Ⅱ. The results of actinomycin D assay showed that miR-34a-5p inhibited the stability of Slit1-3’UTR 1526nt in mCFs， while the level of miR-34a-5p was reduced in mCFs with overexpression of Slit1-3’UTR 1526nt. Transfection of miR-34a-5p promoted the fibrotic phenotypes， and reversed the inhibitory effect of Slit1-3’UTR 1526nt on the fibrotic phenotypes of mCFs. Overexpression of Slit1-3’UTR 1526nt significantly increased the level of miR-34a-5p target gene SIRT1 in mCFs. Transfection of miR-34a-5p and si-SIRT1 consistently reversed the inhibitory effects of Slit1-3’UTR 1526nt on the fibrotic phenotypes of mCFs. ConclusionSlit1-3’UTR1526nt inhibits the fibrotic phenotypes of mCFs by binding to miR-34a-5p and increasing the expression of its target gene of SIRT1.

Aim To explore the mechanism of modified Wuzi Yanzong pill to reduce testicular toxicity of Tripterygium wilfordii by means of network pharmacolo-gy.Methods The effective chemical composition and target of modified Wuzi Yanzong Pill to reduce testicu-lar toxicity of Tripterygium wilfordii were analyzed by using multiple databases to understand the mechanism of action.Results The first five compounds of modi-fied Wuzi Yanzong pill are quercetin,sucrose,kaempferol,galactose and ellagic acid,respectively.The first five targets were TP53,SRC,EP300,MAPK3,STAT3;KEGG pathway enrichment analysis mainly concentrated in cancer pathway,lipid and atherosclero-sis,hepatitis B,apoptosis,diabetes complications AGE-RAGE signaling pathway,PI3K-Akt signaling pathway and other signaling pathways.Conclusions The ac-tive components of modified Wuzi Yanzong pill can re-duce the testicular toxicity of Tripterygium wilfordii mainly by interfering with TP53,SRC,EP300,MAPK3,STAT3 and other targets,regulating apoptosis,PI3K-Akt signaling pathway,diabetes complications AGE-RAGE signaling pathway,lipid metabolism and other pathways.

Objective:To examine the application of a novel pedagogical approach multidimensional supportive psychological intervention(MSPI)in the clinical practice teaching of andrological nursing care.Methods:Using the Hamilton Depression Scale(HAMD),we assessed the psychology of 100 nursing interns about to enter clinical practice in the Department of Andrology from De-cember 2021 to December 2022.We equally randomized the subjects into an experimental and a control group,the former receiving MSPI and the latter trained on the conventional teaching model without any psychological support intervention.Results:Compared with the baseline,the HAMD scores were significantly decreased in the experimental group after intervention(12.4±2.1 vs 8.9±2.4,P＜0.01),but increased in the controls(13.1±1.8 vs 14.7±1.9,P＜0.01);the skill scores dramatically increased in the experimental group(82.6±4.7 vs 91.2±2.4,P＜0.01),but decreased in the control group after intervention(81.0±3.5 vs 80.4±2.7,P=0.28).Conclusion:MSPI can significantly enhance the learning enthusiasm of nursing students in a short period,re-duce their psychological stress and improve teaching outcomes.This approach,combining psychology with teaching,can also strength-en the mental resilience of nursing students and better confront them with future professional challenges.

AIM To study the chemical constituents from the large polar fraction of the roots of Lindera reflexa Hemsl.and their antitumor activities.METHODS The large polar fraction from the roots of L.reflexa was isolated and purified by silica gel column,Sephadex LH-20 gel column,semi-preparative HPLC and ODS medium pressure column,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The antitumor activities were determined by MTT method.RESULTS Thirteen compounds were isolated and identified as 2,6-dimethoxy-4-hydroxyphenyl-1-O-β-D-glucopyranoside(1),3-hydroxy-4,5-dimethoxyphenol-β-D-glucopyranoside(2),syringin(3),1-O-3,4-dimethoxy-5-hydroxyphenyl-(6-O-3,5-dimethoxygalloyl)-β-D-glucopyranoside(4),p-cymen-7-yl β-D-glucopyranoside(5),pisumionoside(6),staphylionoside D(7),dendranthemoside B(8),lynoiside(9),nudiposide(10),icariside B1(11),(2S)-pinocembrin-7-O-(6-O-α-L-rhamnopyranosyl-β-D-glucopyranoside)(12),(+)-N-(methoxycarbonyl)-N-norboldine(13).Compounds 3 and 13 showed obvious cytotoxicity against human lung cancer cells(A549)and human gastric cancer cells(MGC80-3).CONCLUSION Compounds 1-13 are isolated from the roots of L.reflexa for the first time.Compounds 3 and 13 have good anti-tumor activities.

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.

Objective To summarize the distribution characteristics of healthcare-associated infection(HAI)after esophageal cancer surgery,analyze the relevant risk factors for HAI,provide reference for reducing HAI after esophageal cancer surgery,and improve patients'life quality.Methods Clinical data of patients with esophageal cancer who underwent surgery in a hospital from January to December 2022 were analyzed retrospectively.Postope-rative HAI sites and distribution were summarized.Chi-square test,univariate analysis and multivariate analysis were adopted to conduct correlation analysis on the basic characteristics,surgery-related influencing factors,antimi-crobial use,risk factors and the occurrence of HAI in patients during hospitalization period.Results A total of 404 patients underwent esophageal cancer surgery were included in the analysis,among which 102 cases had 118 epi-sodes of HAI,leading to an incidence and a case incidence of HAI of 25.25％and 29.21％respectively.The major infection sites were lower respiratory tract(n=57,48.31％),pleural cavity(n=31,26.27％),and organ space(n=16,13.56％).Multivariate logistic regression analysis showed that age ≥60 years(OR=2.115,95％CI:1.150-3.890),length of hospital stay ≥25 days(OR=8.388,95％CI:4.491-15.667)and duration of postope-rative antimicrobial use ≥10 days(OR=2.885,95％CI:1.506-5.527)were independent risk factors for the oc-currence of postoperative HAI(all P＜0.05).Conclusion The major HAI in patients after esophageal cancer sur-gery is lower respiratory tract infection,and is caused by multiple factors.Patients aged ≥60 years,with a length of hospital stay ≥25 days,and duration of postoperative antimicrobial use ≥10 days are more likely to develop postope-rative HAI.In order to improve the life quality of patients underwent esophageal cancer surgery,it is rec-ommended to further strengthen perioperative management,optimize the nursing quality for patients during hospi-talization,and use antimicrobial agents rationally to reduce the occurrence of HAI.

Objective To clarify the expression and distribution of brain⁃derived neurotrophic factor (BDNF) in the cerebrum of plateau yaks and cattle, and to explore the relationship between BDNF function and the adaptability of altitude hypoxia. Methods Five yaks and five cattles were selected.The content and distribution of BDNF in frontal lobe, temporal lobe, parietal lobe, occipital lobe, cerebrum white matter and hippocampus of yak and cattle were analyzed by Real⁃time PCR, Western blotting and Immunohistochemistry. Results Real⁃time PCR result showed that BDNF mRNA expression in the cerebrum of yaks and cattles was highest in temporal cortex, followed by hippocampus, parietal cortex, occipital cortex and frontal cortex, and lowest in white matter. Western blotting results showed that the content of BDNF protein in the cerebrum of yaks was the highest in temporal cortex,followed by hippocampus. The content of BDNF protein in other tissues was parietal cortex, frontal cortex and cerebrum white matter, and the content of BDNF protein was the lowest in occipital cortex. The content of BDNF protein intlecerebrum of cattles was the highest in the temporal cortex, followed by the hippocampus. The content of BDNF protein in other tissues was parietal cortex, occipital cortex and frontal cortex in descending order, and the protein content in cerebrum white matter was the lowest. Immunohistochemical results showed that the positive expression of BDNF protein in the cerebrum of yaks and cattles was basically similar, mainly distributed in the granulosa cells and glial cells in the frontal cortex, temporal cortex, parietal cortex and occipital cortex, glial cells in cerebrum white matter, pyramidal cell layer and polyform cell layer in the hippocampus. There was the small amount of distribution in Martinotti cells and the molecular layer of hippocampus in the cerebral cortex. Conclusion BDNF mRNA and protein are distributed and expressed in different brain regions of yaks and cattles, but the expression level different, which is speculated to be closely related to the specific functions of different cerebrum regions. The expression level of the cerebrum of yak is higher than that of cattle except occipital cortex, suggesting that it is related to the altitude hypoxic environment. BDNF may play an important role in enhancing hypoxic tolerance and protecting internal environmental homeostasis in the process of animal adaptation to hypoxic environment.

Objective To investigate the prevalence of tick-borne rickettsial infections in selected areas of Liupanshui City, Guizhou Province, 2023, so as to provide insights into the management of tick-borne rickettsioses in the city. Methods Ticks were captured from the body surface of bovines and sheep in Gaoxing Village, Dashan Township, Liupanshui City, Guizhou Province during the period between April and June, 2023, and tick species were identified using morphological and molecular biological techniques. In addition, tick-borne Rickettsia was identified using a nested PCR assay, including spotted fever group rickettsiae (SFGR), Coxiella spp., Anaplasma spp., Ehrlichia spp., and Orientia spp., and positive amplified fragments were sequenced and aligned with known sequences accessed in the GenBank database. Results A total of 200 ticks were collected and all tick species were identified as Rhipicephalus microplus. Nestle PCR assay combined with sequencing identified ticks carrying Candidatus Rickettsia jingxinensis (40.50%), Coxiella burnetii (1.50%), and Coxiella-like endosymbionts (27.00%), and Anaplasma spp., Ehrlichia spp. or Orientsia spp. was not detected. Conclusions R. microplus carried Candidatus R. jingxinensis, C. burnetii, and Coxiella-like endosymbionts in selected areas of Liupanshui City, Guizhou Province. Intensified monitoring of tickborne rickettsial infections is needed in livestock and humans to reduce the damages caused by rickettsioses.

The expression level of NOD-like receptors(NLRP3)inflammasome is significantly elevated in breast cancer tissues,and a high level of NLRP3 inflammasomes is closely associated with breast cancer metastasis.Activation of NLRP3 inflammasome can induce the release of inflammatory factors into the tumor microenvironment(TME).These inflammatory factors,by signaling to cancer cells,reshape the TME to promote tumor growth and invasion,ultimately facilitating the process of epithelial-mesenchymal transition.This equips cancer cells with the ability to establish distant metastases and increase the formation of metastatic lesions.This review addresses the current research status and prospects of NLRP3 inflammasomes in the breast cancer TME and their role in breast cancer metastasis.The goal is to provide new insights for the study of breast cancer metastasis mechanisms and treatment strategies.