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 discuss the role of M2 macrophages in epithelial-mesenchymal transition(EMT)and cisplatin(DDP)resistance in the non-small cell lung cancer(NSCLC),and to clarify the regulatory mechanism of nuclear factor κB(NF-κB)signaling pathway.Methods:The human monocytic leukemia THP-1 cells were selected and differentiated into M0 macrophages by phorbol myristate acetate(PMA)induction,followed by M2 macrophage polarization through interleukin(IL)-4 and IL-13 stimulation.Western blotting and immunofluorescence methods were used to detect the protein expression levels of CD163,CD86,and arginase-1(Arg-1)in M0 and M2 macrophages.The human NSCLC A549 cells were co-cultured non-contactly with M0 or M2 macrophages in Transwell chambers,and the cells were divided into A549+M0 group(A549 cells co-cultured with M0 macrophages),A549+M2 group(A549 cells co-cultured with M2 macrophages),and A549+M2+BAY11-7082 group(A549 cells co-cultured with M2 macrophages and treated with 10 mmol·L-1 NF-κB inhibitor BAY11-7082).Wound healing assay was used to detect the wound healing rate of the A549 cells in various groups;Transwell assay was used to detect the number of invasion A549 cells in various groups;cell counting kit-8(CCK-8)assay was used to detect the inhibitory rate of proliferation and half maximal inhibitory concentration(IC50)value of the A549 cells after treated with DDP in the co-culture system;Western blotting method was used to detect the expression levels of vimentin,E-cadherin,N-cadherin,transcription factor Snail,phosphorylated P65(p-P65),P-glycoprotein(P-gp),and programmed death-ligand 1(PD-L1)proteins in the A549 cells in various groups.Results:The Western blotting results showed that compared with M0 group,the expression levels of CD163 and Arg-1 proteins in the macrophages in M2 group were significantly increased(P<0.05),while the expression level of CD86 protein was significantly decreased(P<0.05).The immunofluorescence results showed that compared with M0 group,the expression of CD163 protein in the macrophages in M2 group was enhanced and the expression of CD86 protein was weakened.The wound healing assay results showed that at 24 and 48 h of culture,compared with A549+M0 group,the wound healing rate of the A549 cells in A549+M2 group was significantly increased(P<0.05);in the co-culture system,compared with A549+M0 group,the wound healing rate of the A549 cells in A549+M2 group was significantly increased(P<0.05);compared with A549+M2 group,the wound healing rate of the A549 cells in A549+M2+BAY11-7082 group was significantly decreased(P<0.05).The Transwell assay results showed that compared with A549+M0 group,the number of invasion A549 cells in A549+M2 group was significantly increased(P<0.05);compared with A549+M2 group,the number of invasion A549 cells in A549+M2+BAY11-7082 group was significantly decreased(P<0.05);in the co-culture system,compared with A549+M0 group,the number of invasion A549 cells in A549+M2 group was significantly increased(P<0.05).The CCK-8 assay results showed that after treated with 2.50,5.00,10.00,20.00,and 40.00 mg·L-1 DDP,compared with A549+M0 group,the inhibitory rate of proliferation of the A549 cells in A549+M2 group was significantly decreased(P<0.05 or P<0.01),and the IC50 value was significantly increased(P<0.01);in the co-culture system,compared with A549+M0 group,the inhibitory rate of proliferation of the A549 cells in A549+M2 group was significantly decreased(P<0.05 or P<0.01),and the IC50 value was significantly increased(P<0.01);compared with A549+M2 group,the inhibitory rate of proliferation of the A549 cells in A549+M2+BAY11-7082 group was significantly increased(P<0.05),and the IC50 value was significantly decreased(P<0.05).The Western blotting results showed that compared with A549+M0 group,the expression level of E-cadherin proteins in the A549 cells in A549+M2 group was significantly decreased(P<0.05),while the expression levels of N-cadherin,vimentin,and Snail proteins were significantly increased(P<0.05);in the co-culture system,compared with A549+M0 group,the expression levels of vimentin,Snail,N-cadherin,and p-P65 proteins in the A549 cells in A549+M2 group were significantly increased(P<0.05),while the expression level of E-cadherin proteins was significantly decreased(P<0.05);compared with A549+M2 group,the expression levels of vimentin,N-cadherin,and p-P65 proteins in the A549 cells in A549+M2+BAY11-7082 group were significantly decreased(P<0.05),while the expression level of E-cadherin proteins was significantly increased(P<0.05);compared with A549+M0 group,the expression levels of P-gp and PD-L1 proteins in the A549 cells in A549+M2 group were significantly increased(P<0.05);in the co-culture system,compared with A549+M0 group,the expression levels of P-gp and PD-L1 proteins in the A549 cells in A549+M2 group were significantly increased(P<0.05);compared with A549+M2 group,the expression levels of P-gp and PD-L1 proteins in the A549 cells in A549+M2+BAY11-7082 group were significantly decreased(P<0.05).Conclusion:The M2 macrophages can regulate EMT in the NSCLC cells to promote the invasion and metastasis of tumor,and modulate the expressions of P-gp and PD-L1 to enhance DDP resistance,which is associated with the NF-κB signaling pathway.

This study explored the effects and underlying mechanism of Raf kinase inhibitory protein(RKIP)on apoptosis in mast cells sensitized by Echinococcus granulosus cyst fluid.Bone marrow-derived mast cells(BMMCs)were isolated and cultured from RKIP knockout(KO)and wild-type(WT)C57BL/6 mice.Cells were divided into control and sensitized groups.The sensitized group was incubated for 24 h in RPMI1640 medium containing 10%serum from mice infected with E.granulosus,then activated for 3 h or 6 h with E.granulosus cyst fluid.The control group was incubated for 24 h in RPMI1640 medium,and then received an equal vol-ume of PBS.Cells and supernatants were collected for analysis.Flow cytometry was used to detect the expression of CD117 and FcεRⅠα on BMMCs.The levels of β-hexosaminidase,IL-4,and TNF-α in the supernatant were quantified with ELISA.Western blot analy-sis was used to assess expression changes in RKIP,apoptosis-related proteins,and pathway proteins in BMMC before and after sensi-tization.Flow cytometry analysis revealed that after 4 weeks of induction,the CD117 and FcεRⅠα double-positivity rates on both WT and KO BMMC exceeded 90%.ELISA indicated that the E.granulosus cyst fluid resulted in significantly greater β-hexosaminidase re-lease(F=16.88,P<0.05),and levels of IL-4(F=16.51,P<0.05)and TNF-α(F=9.78,P<0.05)in the KO sensitized group than the WT sensitized group.With respect to the WT control group,the WT sensitized group showed significantly down-regulated pro-tein expression levels of RKIP(F=8.20,P<0.05)and Bcl-2(F=101.40,P<0.01)after 3 h,but significantly up-regulated levels of p-PI3K(F=8.04,P<0.05),p-Akt(F=32.52,P<0.01),p-P65(F=13.29,P<0.05),and cleaved-caspase-3(F=46.34,P<0.01).With respect to the WT sensitized group,the KO sensitized group showed significantly up-regulated protein expression of p-PI3K(F=8.45,P<0.05),p-Akt(F=8.58,P<0.05),p-P65(F=11.02,P<0.05),and Bcl-2(F=84.50,P<0.001)after 3 h,but significantly down-regulated expression of cleaved-caspase-3(F=15.66,P<0.05).In conclusion,RKIP may inhibit the PI3K/Akt/NF-κB pathway,thereby inducing apoptosis in mast cells sensitized by E.granulosus cyst fluid.This process may help ease aller-gic reactions caused by mast cells in echinococcosis,thus offering a promising new approach for preventing and treating such reactions.

This study explored the effects and underlying mechanism of Raf kinase inhibitory protein(RKIP)on apoptosis in mast cells sensitized by Echinococcus granulosus cyst fluid.Bone marrow-derived mast cells(BMMCs)were isolated and cultured from RKIP knockout(KO)and wild-type(WT)C57BL/6 mice.Cells were divided into control and sensitized groups.The sensitized group was incubated for 24 h in RPMI1640 medium containing 10%serum from mice infected with E.granulosus,then activated for 3 h or 6 h with E.granulosus cyst fluid.The control group was incubated for 24 h in RPMI1640 medium,and then received an equal vol-ume of PBS.Cells and supernatants were collected for analysis.Flow cytometry was used to detect the expression of CD117 and FcεRⅠα on BMMCs.The levels of β-hexosaminidase,IL-4,and TNF-α in the supernatant were quantified with ELISA.Western blot analy-sis was used to assess expression changes in RKIP,apoptosis-related proteins,and pathway proteins in BMMC before and after sensi-tization.Flow cytometry analysis revealed that after 4 weeks of induction,the CD117 and FcεRⅠα double-positivity rates on both WT and KO BMMC exceeded 90%.ELISA indicated that the E.granulosus cyst fluid resulted in significantly greater β-hexosaminidase re-lease(F=16.88,P<0.05),and levels of IL-4(F=16.51,P<0.05)and TNF-α(F=9.78,P<0.05)in the KO sensitized group than the WT sensitized group.With respect to the WT control group,the WT sensitized group showed significantly down-regulated pro-tein expression levels of RKIP(F=8.20,P<0.05)and Bcl-2(F=101.40,P<0.01)after 3 h,but significantly up-regulated levels of p-PI3K(F=8.04,P<0.05),p-Akt(F=32.52,P<0.01),p-P65(F=13.29,P<0.05),and cleaved-caspase-3(F=46.34,P<0.01).With respect to the WT sensitized group,the KO sensitized group showed significantly up-regulated protein expression of p-PI3K(F=8.45,P<0.05),p-Akt(F=8.58,P<0.05),p-P65(F=11.02,P<0.05),and Bcl-2(F=84.50,P<0.001)after 3 h,but significantly down-regulated expression of cleaved-caspase-3(F=15.66,P<0.05).In conclusion,RKIP may inhibit the PI3K/Akt/NF-κB pathway,thereby inducing apoptosis in mast cells sensitized by E.granulosus cyst fluid.This process may help ease aller-gic reactions caused by mast cells in echinococcosis,thus offering a promising new approach for preventing and treating such reactions.

[Objective] To understand the resistance mechanisms, virulence characteristics, and pathogenicity of hypervirulent Klebsiella pneumoniae (hvKp), which causes pyogenic liver abscess (PLA), and to provide related data for clinical treatment of infection caused by this type of bacteria. [Methods] We collected three strains of Klebsiella pneumoniae isolated from the liver abscess fluid of patients with liver abscesses in various departments of The First Affiliated Hospital of Xi’an Jiaotong University. The hypervirulent phenotypes were determined by the wire test, and drug sensitivity was assessed using the VITEK 2 compact automatic microbiological analyzer. Molecular characteristics such as podocarp serotypes, multi-locus sequence typing (MLST), virulence genes, and drug resistance genes were identified through whole-genome sequencing. Additionally, a mouse infection model was established to evaluate pathogenicity. [Results] The isolates were sticky, with mucous thread pulling length >5 mm, all of which exhibited high viscosity phenotypes. Except 146007, which is a multidrug-resistant bacterium, the other two strains had higher antibiotic sensitivity. Whole genome sequencing revealed that the isolates were of high-virulence type, carrying the toxin plasmid rmpADC/rmpA2, iron uptake system, bacterial hairs, secretion system, and other virulence factors. All the three isolates tested positive for rmpA/rmpA2 combined with iucA/iutA, indicating they could be classified as hvKp. Multiple resistance genes were detected, such as β-lactamase like blaTEM, blaSHV, and blaCTX-M. The isolates were highly pathogenic to mice, as evidenced by the diseased organs of the deceased mice observed on autopsy. [Conclusion] The three strains of hvKp isolated in this study carried multiple drug-resistant genes and were highly pathogenic, which suggests that in laboratories and clinical practices it is imperative to promptly identify and adopt necessary disposal strategies to prevent further spread of hvKp.

Our understanding of facial anatomy has changed significantly over the past decade. With the emergence of numerous minimally invasive facial rejuvenation techniques, facial anatomy theory witnesses continuous development. Nowadays, temporal region-related surgeries are developing towards being with less trauma and higher safety, and further in-depth anatomical studies are conducted on the temporal branch of the facial nerve. Familiarity with the course direction, branch distribution, and position of body surface projection of the temporal branch of the facial nerve is of great importance to protect the temporal branch of the facial nerve and its branches from injury. This article summarizes and analyzes the current relevant literature thus provides critical morphological data for head and neck plastic surgery and aesthetic surgery, along with some guidance in clinical application.

Our understanding of facial anatomy has changed significantly over the past decade. With the emergence of numerous minimally invasive facial rejuvenation techniques, facial anatomy theory witnesses continuous development. Nowadays, temporal region-related surgeries are developing with trends of less trauma and higher safety, and further in-depth anatomical studies are conducted on the temporal branch of the facial nerve. Familiarity with the course direction, branch distribution, and position of body surface projection regarding the temporal branch of the facial nerve is crucial to protect these branches from injury. This article summarizes and analyzes the current relevant literatures thus provides critical morphological data for head and neck plastic surgery and aesthetic surgery, along with some guidance in clinical application.

OBJECTIVE: To evaluate the prospective association between cumulative resting heart rate (cumRHR) and rapid renal function decline (RRFD) in a cohort of individuals aged 60 and older. METHODS: In the Tianjin Chronic Kidney Disease Cohort Study, the individuals who underwent three consecutive physical examinations between 2014 and 2017, with estimated glomerular filtration rate (eGFR) greater than 60 mL/min per 1.73 m² and aged 60 years or older were enrolled. A total of 27,564 patients were prospectively followed up from January 1, 2017 to December 31, 2020. The 3-year cumRHR was calculated. The primary outcome was RRFD, defined as an annualized decline in eGFR of 5 mL/min per 1.73 m² or greater. Logistic and restricted spline regression models and subgroup analysis were used to investigate the association of cumRHR with RRFD after adjusting for all confounders. RESULTS: During a median follow-up of 3.2 years, a total of 4,347 (15.77%) subjects developed RRFD. In fully-adjusted models, compared with the lowest quartile of cumRHR, the odds ratio (OR) for the highest was 1.44 (1.28-1.61), P < 0.001. Furthermore, each 1-standard deviation (27.97 beats/min per year) increment in cumRHR was associated with a 17% (P < 0.001) increased risk of RRFD, with a linear positive correlation (P for non-linear = 0.803). Participants with a 3-year cumRHR ≥ 207 (beats/min) * year (equivalent to ≥ 69 beats/min per year in 3 years) were found to be at a higher risk of RRFD. CONCLUSIONS The cumRHR is significantly associated with a higher risk of RRFD among older adults. These results might provide an effective goal for managing and delaying the decline of renal function in the older adults.

Our understanding of facial anatomy has changed significantly over the past decade. With the emergence of numerous minimally invasive facial rejuvenation techniques, facial anatomy theory witnesses continuous development. Nowadays, temporal region-related surgeries are developing towards being with less trauma and higher safety, and further in-depth anatomical studies are conducted on the temporal branch of the facial nerve. Familiarity with the course direction, branch distribution, and position of body surface projection of the temporal branch of the facial nerve is of great importance to protect the temporal branch of the facial nerve and its branches from injury. This article summarizes and analyzes the current relevant literature thus provides critical morphological data for head and neck plastic surgery and aesthetic surgery, along with some guidance in clinical application.

Our understanding of facial anatomy has changed significantly over the past decade. With the emergence of numerous minimally invasive facial rejuvenation techniques, facial anatomy theory witnesses continuous development. Nowadays, temporal region-related surgeries are developing with trends of less trauma and higher safety, and further in-depth anatomical studies are conducted on the temporal branch of the facial nerve. Familiarity with the course direction, branch distribution, and position of body surface projection regarding the temporal branch of the facial nerve is crucial to protect these branches from injury. This article summarizes and analyzes the current relevant literatures thus provides critical morphological data for head and neck plastic surgery and aesthetic surgery, along with some guidance in clinical application.