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.

Objective:To study the diagnostic value of artificial intelligence B-ultrasound image computer-aided diagnosis system (hereinafter referred to as intelligent ultrasound system) in adult goiter.Methods:In June 2022 and March 2023, two phases of thyroid disease survey were carried out in 4 cities in Anhui Province. One village was selected in each city, and 250 adults were selected as survey subjects in each village. Adult bilateral thyroid area was scanned by both intelligent ultrasound system and conventional ultrasound scanning equipment, and the effectiveness of intelligent ultrasound system in the diagnosis of goiter was analyzed based on the results of conventional ultrasound examination. Receiver operating characteristic (ROC) curve was drawn, and Kappa test was used to analyze the consistency between intelligent ultrasound system and conventional ultrasound examination in the diagnosis of goiter. At the same time, Spearman correlation analysis and Bland-Altman method were used to evaluate the consistency of the two methods in measuring thyroid volume.Results:After screening and removing outliers and missing values, a total of 910 adults were included, including 253 males (27.80%) and 657 females (72.20%). The age was (45.92 ± 10.20) years old, ranging from 18 to 60 years old. The sensitivity, specificity, and accuracy of the intelligent ultrasound system for diagnosing adult goiter were 80.00%, 99.67%, and 99.56%, respectively. The area under the ROC curve (AUC) was 0.996, which was consistent with the results of conventional ultrasound examination for diagnosing goiter ( κ = 0.67, P < 0.001). After controlling for variables such as gender, thyroid function, and thyroid nodules, the intelligent ultrasound system showed good consistency with conventional ultrasound examination in the diagnosis of goiter in females, adults with thyroid dysfunction, and adults without thyroid nodules ( κ = 0.66, 0.80, 0.80, P < 0.001). The consistency in the diagnosis of goiter in adults with thyroid nodules was moderate ( κ = 0.56, P < 0.001). Spearman correlation analysis showed a highly positive correlation between the measurement results of adult thyroid volume by intelligent ultrasound system and conventional ultrasound examination ( r = 0.88, P < 0.001). The Bland-Altman method results showed that only 4.62% (42/910) of points in adults were outside the 95% consistency limit, indicating good consistency between intelligent ultrasound system and conventional ultrasound examination in measuring thyroid volume (< 5%). The proportion of points outside the 95% consistency limit in males, adults with thyroid dysfunction, and adults with thyroid nodules was 6.72% (17/253), 5.83% (12/206), and 6.45% (12/186), respectively. Conclusions:The intelligent ultrasound system has certain diagnostic value for adult goiter and has good consistency with conventional ultrasound examination for thyroid volume measurement. However, the accuracy of diagnosis for males and adults with thyroid nodules still needs to be improved.

Objective:To investigate the mechanism of polygonatum and astragalus compound(PA)in inhibiting the progression of lung adenocarcinoma. Methods:CCK-8 assay was used to assess the inhibitory rate of proliferation in A549 and H1299 cells treated with PA at different concentrations and to calculate the half maximal inhibitory concentration(IC50).C57BL/6 mice(KRASG12D/+;TP53flox/flox)were treated with adenovirus carrying Cre enzyme via nasal inhalation to establish a mouse model of primary lung adenocarcinoma.The model mice were fed with PA-containing diet to directly observe the effect of PA on the lung adenocarcinoma tissue.Immunohistochemical staining was used to examine the pathological status of the lung tissue.Bioinformatics analysis indicated that PA affects the progression of lung adenocarcinoma through the apelin-peroxisome proliferator-activated receptor gamma coactivator 1-alpha(PGC1α)-mitochondrial brown fat uncoupling protein 1(UCP1).Real-time quantitative PCR and Western blotting analysis were used to study the effect of PA on the mRNA and protein expression levels of apelin-PGC1α-UCP1 signaling pathway related genes.An ATP detection kit and flow cytometry were used to evaluate the effect of PA on the ATP and mitochondrial ROS production,respectively,in A549 and H1299 cells.siUCP1 was used to silent the expression of UCP1 while Z160 was used to induce UCP1 overexpression in A549 and H1299 cells,and the changes in ATP and mitochondrial ROS production were examined to further investigate whether PA acts on apelin-PGC1α-UCP1 signaling pathway to affect the progression of lung adenocarcinoma. Results:PA could obviously inhibit the proliferation of A549 and H1299 cells with the IC50 values of 10.66 mg/mL for A549 cells and 9.66 mg/mL for H1299 cells.In the mouse primary lung adenocarcinoma model,PA could effectively inhibit the growth of tumor,downregulate apelin-PGC1α-UCP1 signaling pathway and inhibit the expression of lung adenocarcinoma-promoting gene UCP1.In A549 and H1299 cells,PA could significantly inhibit the expression of apelin,PGC1α and UCP1(P＜0.05),promote the production of ATP(P＜0.000 1)and ROS,restore mitochondrial oxidative phosphorylation,and inhibit aerobic glycolysis(P＜0.01).UCP1 silencing could increase the production of ATP(P＜0.01)and mitochondrial ROS and decrease the expression of key glycolysis enzymes hexokinase 2(HK2)and pyruvate kinase isozyme type M2(PKM2)(P＜0.05).Increasing the expression of UCP1 could reduce the ATP production(P＜0.01)and mitochondrial ROS generation in cells while increase the expression of HK2 and PKM2(P＜0.05).Treating cells with PA and Z160 simultaneously(PA+Z160)could reverse the inhibitory effect of PA on the ATP production and glycolysis of tumor cells(P＜0.05). Conclusion:PA can downregulate the apelin-PGC1α-UCP1 signaling pathway,inhibit mitochondrial uncoupling,restore mitochondrial oxidative phosphorylation,inhibit aerobic glycolysis,reverse the Warburg effect,and thus inhibit lung adenocarcinoma progression.

AIM: To study the effects of long-term use of clozapine on tear film stability and ocular surface tissue structure.METHODS: Case-control study was conducted on 45 patients(group 1)who were diagnosed with schizophrenia and treated with clozapine for 3.45±0.72a between March 2021 and December 2021. Another 45 healthy subjects(group 2)served as controls, whose demographic characteristics were similar to those of group 1. Patients' dry eye symptoms were investigated using OSDI questionnaire, tear secretion was detected by the Schirmer I test, ocular surface damage was assessed by the ocular surface staining score, and comprehensive ophthalmic examination was performed on all patients through LipiView ocular surface interferometer, ocular surface integrated analyzer, corneal confocal microscope and slit lamp photographic system.RESULTS: Slit-lamp photography showed diffuse grayish-white spot-like opacification in the corneal stroma of group 1, accompanied by brown star-like opacification in the center of the anterior capsule of the lens. OSDI scores were 38.00(31.50, 48.50)and 15.00(9.00, 19.50)in the two groups respectively. Schirmer test showed that the group 1 was 5.27±2.18mm/5min, while group 2 was 15.62±3.05mm/5min. Corneal fluorescein staining score: 4.00(2.50, 5.00)for group 1 and 1.00(0.00, 1.50)for group 2. The lissamine green staining score for the conjunctiva was 9.00(6.50, 10.00)and 3.00(2.00, 3.50)for the two groups, respectively. LipiView detected lipid layer thickness(LLT), suggesting that the results of group 1 and group 2 were similar, respectively 75.91±15.51 and 77.24±12.11nm; and the results were similar for the lid gland deficiency score, with 1.37±0.26 and 1.29±0.31 points, respectively. The mean tear meniscus height in group 1 was 0.13±0.06mm, which was lower than 0.23±0.04mm of group 2. Non-invasive breakup time(NIBUT)was 6.04±2.62 and 11.4±2.74s in group 1 and group 2 respectively. OSDI score, Schirmer Ⅰ test, ocular surface staining score, tear meniscus height and NIBUT were significantly different between the two groups(P<0.05). Confocal corneal microscopy suggested decreased corneal nerve fiber density with stromal layer inflammatory cell infiltration and pigmentation in group 1.CONCLUSION: The antipsychotic drug clozapine can induce dry eye with a range of ocular surface injuries such as corneal pigmentation, and patients who taking such drugs should be routinely examined by an ophthalmologist.

Adult ; Humans ; Retrospective Studies ; Pneumonia ; Community-Acquired Infections/epidemiology* ; Hospitalization

This study was aimed to investigate the effect of hypoxia on lipopolysaccharide (LPS)-induced CXC-chemokine ligand-10 (CXCL10) expression and the underlying mechanism. C57BL/6J mice were randomly divided into control, hypoxia, LPS, and hypoxia combined with LPS groups. The LPS group was intraperitoneally injected with 0.5 mg/kg LPS, and the hypoxia group was placed in a hypobaric hypoxia chamber (simulated altitude of 6 000 m). The serum and hippocampal tissue samples were collected after 6 h of the treatment. The levels of CXCL10 in the serum and hippocampal tissue of mice were detected by ELISA. The microglia cell line BV2 and primary microglia were stimulated with hypoxia (1% O₂) and/or LPS (100 ng/mL) for 6 h. The mRNA expression level of CXCL10 and its content in culture supernatant were detected by real-time quantitative PCR and ELISA, respectively. The phosphorylation levels of nuclear factor κB (NF-κB) signaling pathway-related proteins, p65 and IκBα, were detected by Western blot. Moreover, after NF-κB signaling pathway being blocked with a small molecular compound, PDTC, CXCL10 mRNA expression level was detected in the BV2 cells. The results showed that in the LPS-induced mouse inflammatory model, hypoxia treatment could promote LPS-induced up-regulation of CXCL10 in both serum and hippocampus. Compared with the cells treated with LPS alone, the expression of CXCL10 mRNA and the content of CXCL10 in the culture supernatant of BV2 cells treated with hypoxia combined with LPS were significantly increased. The CXCL10 mRNA level of primary microglial cells treated with hypoxia combined with LPS was significantly up-regulated. Compared with the cells treated with hypoxia or LPS alone, the phosphorylation levels of p65 and IκBα in the BV2 cells treated with hypoxia combined with LPS were significantly increased. PDTC blocked the induction of CXCL10 gene expression by LPS in the BV2 cells. These results suggest that hypoxia promotes LPS-induced expression of CXCL10 in both animal and cell models, and NF-κB signaling pathway plays an important role in this process.
Animals ; Mice ; Chemokines, CXC/pharmacology* ; Hypoxia ; Ligands ; Lipopolysaccharides/pharmacology* ; Mice, Inbred C57BL ; Microglia/metabolism* ; NF-kappa B/metabolism* ; NF-KappaB Inhibitor alpha/pharmacology* ; RNA, Messenger/metabolism*

Objective: The docking and superantigen activity sites of staphylococcal enterotoxin-like W (SElW) and T cell receptor (TCR) were predicted, and its SElW was cloned, expressed and purified. Methods: AlphaFold was used to predict the 3D structure of SElW protein monomers, and the protein models were evaluated with the help of the SAVES online server from ERRAT, Ramachandran plot, and Verify_3D. The ZDOCK server simulates the docking conformation of SElW and TCR, and the amino acid sequences of SElW and other serotype enterotoxins were aligned. The primers were designed to amplify selw, and the fragment was recombined into the pMD18-T vector and sequenced. Then recombinant plasmid pMD18-T was digested with BamHⅠand Hind Ⅲ. The target fragment was recombined into the expression plasmid pET-28a(+). After identification of the recombinant plasmid, the protein expression was induced by isopropyl-beta-D- thiogalactopyranoside. The SElW expressed in the supernatant was purified by affinity chromatography and quantified by the BCA method. Results: The predicted three-dimensional structure showed that the SElW protein was composed of two domains, the amino-terminal and the carboxy-terminal. The amino-terminal domain was composed of 3 α-helices and 6 β-sheets, and the carboxy-terminal domain included 2 α-helices and 7 antiparallel β-sheets composition. The overall quality factor score of the SElW protein model was 98.08, with 93.24% of the amino acids having a Verify_3D score ≥0.2 and no amino acids located in disallowed regions. The docking conformation with the highest score (1 521.328) was selected as the analysis object, and the 19 hydrogen bonds between the corresponding amino acid residues of SElW and TCR were analyzed by PyMOL. Combined with sequence alignment and the published data, this study predicted and found five important superantigen active sites, namely Y18, N19, W55, C88, and C98. The highly purified soluble recombinant protein SElW was obtained with cloning, expression, and protein purification. Conclusions: The study found five superantigen active sites in SElW protein that need special attention and successfully constructed and expressed the SElW protein, which laid the foundation for further exploration of the immune recognition mechanism of SElW.
Humans ; Enterotoxins/genetics* ; Superantigens/genetics* ; Catalytic Domain ; Selenoprotein W/metabolism* ; Receptors, Antigen, T-Cell

Objective: To establish a dynamic syndromic surveillance system in the border areas of Yunnan Province based on information technology, evaluate its effectiveness and timeliness in the response to common communicable disease epidemics and improve the communicable disease prevention and control in border areas. Methods: Three border counties were selected for full coverage as study areas, and dynamic surveillance for 14 symptoms and 6 syndromes were conducted in medical institutions, the daily collection of information about students' school absence in primary schools and febrile illness in inbound people at border ports were conducted in these counties from January 2016 to February 2018 to establish an early warning system based on mobile phone and computer platform for a field experimental study. Results: With syndromes of rash, influenza-like illness and the numbers of primary school absence, the most common communicable disease events, such as hand foot and mouth disease, influenza and chickenpox, can be identified 1-5 days in advance by using EARS-3C and Kulldorff time-space scanning models with high sensitivity and specificity. The system is easy to use with strong security and feasibility. All the information and the warning alerts are released in the form of interactive charts and visual maps, which can facilitate the timely response. Conclusions: This system is highly effective and easy to operate in the detection of possible outbreaks of common communicable diseases in border areas in real time, so the timely and effective intervention can be conducted to reduce the risk of local and cross-border communicable disease outbreaks. It has practical application value.
Humans ; Influenza, Human ; Sentinel Surveillance ; Syndrome ; China ; Cell Phone

Objective: To understand the population structure of food-borne Staphylococcus (S.) aureus in China. Methods: Whole genome sequencing was used to analyze 763 food-borne S. aureus strains from 16 provinces in China from 2006 to 2020. Multilocus sequence typing (MLST), staphylococcal protein A gene (spa) typing, and staphylococcal chromosome cassettemec (SCCmec) typing were conducted, and minimum spanning tree based on ST types (STs) was constructed by BioNumerics 7.5 software. Thirty-one S. aureus strains isolated from imported food products were also included in constructing the genome phylogenetic tree. Results: A total of 90 STs (20 novel types) and 160 spa types were detected in the 763 S. aureus isolates. The 72 STs (72/90, 80.0%) were related to 22 clone complexes. The predominant clone complexes were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, accounting for 82.44% (629/763) of the total. The STs and spa types in the predominant clone complexes changed over the years. The methicillin-resistant S. aureus (MRSA) detection rate was 7.60%, and 7 SCCmec types were identified. The ST59-t437-Ⅳa (17.24%, 10/58), ST239-t030-Ⅲ (12.07%, 7/58), ST59-t437-Ⅴb (8.62%, 5/58), ST338-t437-Ⅴb (6.90%, 4/58) and ST338-t441-Ⅴb (6.90%, 4/58) were the main types in MRSA strains. The genome phylogenetic tree had two clades, and the strains with the same CC, ST, and spa types clustered together. All CC7 methicillin sensitive S. aureus strains were included in Clade1, while 21 clone complexes and all MRSA strains were in Clade2. The MRSA strains clustered according to the SCCmec and STs. The strains from imported food products in CC398, CC7, CC30, CC12, and CC188 had far distances from Chinese strains in the tree. Conclusions: In this study, the predominant clone complexes of food-borne strains were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, which overlapped with the previously reported clone complexes of hospital and community-associated strains in China, suggesting that close attention needs to be paid to food, a vehicle of pathogen transmission in community and food poisoning.
Humans ; Staphylococcus aureus/genetics* ; Methicillin-Resistant Staphylococcus aureus/genetics* ; Multilocus Sequence Typing ; Phylogeny ; Staphylococcal Infections/epidemiology* ; China/epidemiology*

To clarify the content characteristics of the main active components and mineral elements of Cynomorium songaricum under different habitat conditions, and further explore the relationship between the quality of C. songaricum and habitats, this study took C. songaricum from 25 different habitats in China as the research object, and measured the contents of 8 main active components and 12 mineral elements separately. Diversity analysis, correlation analysis, principal component analysis and cluster analysis were carried out. The results showed that the genetic diversity of total flavonoids, ursolic acid, ether extract, potassium(K), phosphorus(P) and zinc(Zn) in C. songaricum was high. The coefficient of variation of crude polysaccharide, ether extract, gallic acid, protocatechuic aldehyde, catechin, epicatechin, calcium(Ca), sodium(Na), magnesium(Mg), sulfur(S), iron(Fe), manganese(Mn), selenium(Se) and nickel(Ni) were all over 36%, indicating that the quality of C. songaricum was significantly affected by habitats. There were strong synergistic and weak antagonistic effects among the contents of the 8 active components, and complex antagonistic and synergistic effects among the contents of the 12 mineral elements. Principal component analysis revealed that crude polysaccharide, ursolic acid, catechin, epicatechin and total flavonoids could be used as the characteristic components to evaluate the quality of C. songaricum, and Na, copper(Cu), Mn and Ni were the characteristic elements to evaluate the quality of C. songaricum. In cluster ana-lysis, the second group with the main active components as cluster center had better quality in terms of the content of active substances, and the second group with the mineral elements as cluster center had higher utilization potential in the exploitation of mineral elements. This study could provide a basis for resource evaluation and breeding of excellent varieties of C. songaricum in different habitats, and provide a reference for cultivation and identification of C. songaricum.
Cynomorium ; Catechin ; Plant Breeding ; Selenium ; Ethers ; Ethyl Ethers ; Flavonoids ; Plant Extracts