Objective:This study aimed to explore the molecular mechanisms of the maladaptation of H3N2 influenza virus in chicken embryos, provide a theoretical basis for the restoration of H3N2 influenza vaccine production in chicken embryos.Methods:Samples of respiratory secretions from patients with influenza-like symptoms (Influenza-like Illness, ILI) caused by H3N2 influenza virus were inoculated into chicken embryos and Madin-Darby Canine Kidney cells (MDCK), respectively. After isolating the virus, hemagglutination experiments were conducted to detect hemagglutination titers and hemagglutination inhibition experiments were used to compare antigenic differences; further, whole-genome sequencing of H3N2 influenza virus was performed using second-generation high-throughput gene sequencing (Next Generation High-Throughput Gene Sequencing, NGS), and key amino acid sites of mutations were identified through sequence alignment; combined with sialic acid receptor binding experiments, the differences in the binding of wild-type and mutant receptor binding sites (RBS) to sialic acid receptors were compared; finally, molecular docking and molecular dynamics simulation method were used to explore the specific molecular mechanisms of how mutation sites affect the differences in the affinity of the RBS pocket for sialic acid receptors.Results:The hemagglutination assay result indicated that both chicken embryos and MDCK cells could isolate the influenza virus, and the hemagglutination inhibition test showed that no antigenic differences were produced in the isolated strains. NGS analysis revealed that the H3N2 virus underwent an F195Y mutation in the (RBS) region of the hemagglutinin (HA) protein after adaptation through chicken embryo passages. Receptor-binding experiments demonstrated that the F195Y mutation enhanced the virus′s binding ability to α2, 3-linked sialic acid glycan (Neu5Acα2-3Galβ1-4GlcNAcβ-PAA, 3′SLN), while the mutation did not affect the affinity of the RBS pocket for α2, 6-linked sialic acid glycan (Neu5Acα2-6Galβ1-4GlcNAcβ-PAA, 6′SLN). Molecular docking and molecular dynamics simulation result indicate that the F195Y mutation, by replacing a hydrophobic amino acid with a hydrophilic one, leads to a significant decrease in the structure of the RBS pocket, enhancing the binding stability of the H3N2 influenza virus with α2, 3-sln. This is specifically manifested by an increase in binding time and an increase in the number of hydrogen bonds at the RBS site with the receptor. Furthermore, the F195Y mutation does not alter the binding of the virus to other receptors.Conclusions:The F195Y mutation in the RBS pocket of H3N2 influenza virus is a key site affecting the viral chicken embryo inadaptability.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that affects upper and lower motor neurons, and its mechanism has not been fully elucidated. In recent years, studies have shown that TAR DNA binding protein-43 (TDP-43) can affect neuronal function through multiple pathways and is closely related to the clinical manifestations and prognoses of ALS patients, suggesting that TDP-43 pathology may be an important target for the diagnosis and treatment of ALS. This article reviews the research progress on role of TDP-43 pathology in pathological mechanism of ALS and its application in diagnosis and treatment of ALS, aiming to provide reference for diagnosis and treatment of ALS.

Objective:This study aimed to explore the molecular mechanisms of the maladaptation of H3N2 influenza virus in chicken embryos, provide a theoretical basis for the restoration of H3N2 influenza vaccine production in chicken embryos.Methods:Samples of respiratory secretions from patients with influenza-like symptoms (Influenza-like Illness, ILI) caused by H3N2 influenza virus were inoculated into chicken embryos and Madin-Darby Canine Kidney cells (MDCK), respectively. After isolating the virus, hemagglutination experiments were conducted to detect hemagglutination titers and hemagglutination inhibition experiments were used to compare antigenic differences; further, whole-genome sequencing of H3N2 influenza virus was performed using second-generation high-throughput gene sequencing (Next Generation High-Throughput Gene Sequencing, NGS), and key amino acid sites of mutations were identified through sequence alignment; combined with sialic acid receptor binding experiments, the differences in the binding of wild-type and mutant receptor binding sites (RBS) to sialic acid receptors were compared; finally, molecular docking and molecular dynamics simulation method were used to explore the specific molecular mechanisms of how mutation sites affect the differences in the affinity of the RBS pocket for sialic acid receptors.Results:The hemagglutination assay result indicated that both chicken embryos and MDCK cells could isolate the influenza virus, and the hemagglutination inhibition test showed that no antigenic differences were produced in the isolated strains. NGS analysis revealed that the H3N2 virus underwent an F195Y mutation in the (RBS) region of the hemagglutinin (HA) protein after adaptation through chicken embryo passages. Receptor-binding experiments demonstrated that the F195Y mutation enhanced the virus′s binding ability to α2, 3-linked sialic acid glycan (Neu5Acα2-3Galβ1-4GlcNAcβ-PAA, 3′SLN), while the mutation did not affect the affinity of the RBS pocket for α2, 6-linked sialic acid glycan (Neu5Acα2-6Galβ1-4GlcNAcβ-PAA, 6′SLN). Molecular docking and molecular dynamics simulation result indicate that the F195Y mutation, by replacing a hydrophobic amino acid with a hydrophilic one, leads to a significant decrease in the structure of the RBS pocket, enhancing the binding stability of the H3N2 influenza virus with α2, 3-sln. This is specifically manifested by an increase in binding time and an increase in the number of hydrogen bonds at the RBS site with the receptor. Furthermore, the F195Y mutation does not alter the binding of the virus to other receptors.Conclusions:The F195Y mutation in the RBS pocket of H3N2 influenza virus is a key site affecting the viral chicken embryo inadaptability.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that affects upper and lower motor neurons, and its mechanism has not been fully elucidated. In recent years, studies have shown that TAR DNA binding protein-43 (TDP-43) can affect neuronal function through multiple pathways and is closely related to the clinical manifestations and prognoses of ALS patients, suggesting that TDP-43 pathology may be an important target for the diagnosis and treatment of ALS. This article reviews the research progress on role of TDP-43 pathology in pathological mechanism of ALS and its application in diagnosis and treatment of ALS, aiming to provide reference for diagnosis and treatment of ALS.

Objective To explore the efficacy and safety of TACE combined with propranolol for treating giant infantile hepatic hemangioma(IHH).Methods Ten infants with giant IHH who underwent TACE combined with propranolol were retrospectively enrolled.The technical success rate,complications and recurrence were recorded.The therapeutic effect was evaluated according to clinical symptoms and changes of IHH volume before and 6 months after TACE.Results Totally 15 times of TACE were successfully performed in 10 infants,with technical success rate of 100%.Bleomycin-lipiodol emulsion+poly(vinyl alcohol)(PVA)+coil embolization were performed in 3 cases,while bleomycin-lipiodol emulsion+PVA embolization were performed in 7 cases.Complications of TACE included subcutaneous hematoma around the puncture site in 1 case and transient hypothermia within 24 h after TACE in 2 cases,all alleviated after symptomatic treatments.No other complication occurred.Six months after the last TACE,significantly effective was observed in 9 cases(9/10,90.00%),while effective was noticed in 1 case(1/10,10.00%),with total therapeutic effective rate of 100%.No serious complication such as gallbladder necrosis,liver necrosis,death,nor recurrence of hepatic hemangioma occurred during follow-up.Conclusion TACE combined with propranolol was effective and safe for treating giant IHH.

With the widespread use of carbapenem antibiotics,the clinical detection rate of carbapenem-resistant Gram-negative bacilli has shown a significant increase.Carbapenem-resistant Gram-negative bacilli isolates are often extensively or fully resistant,resulting in limited antimicrobial treatment options and high morbidity and mortality rates,posing a serious public health threat.The clinical treatment of carbapenem-resistant Gram-negative bacilli includes the use of single or combination antimicrobials such as polymyxin,tigecycline,and fosfomycin.A number of new antimicrobials and therapeutic approaches are under development.The clinical management of carbapenem-resistant Gram-negative infections is severely challenged by the limited choice of antimicrobial agents.Therefore,this article reviews the current status and progress of antimicrobial treatment for carbapenem-resistant Gram-negative bacilli to providing clinical reference.

Objective A HPLC-quantitative analysis of multi-components by single marker(QAMS)was established to determine 5 ingredients including uracil,uridine,hypoxanthine,inosine and guanosine in Periplaneta americana.Methods Separation took place on a Agilent ZORBAX SB-Aq column(250 mm×4.6 mm,5 μm)by gradient elution of methanol-0.01 mol·L-1 potassium dihydrogen phosphate at 20℃with a flow rate of 1.0 mL·min-1.The detection wavelength was 260 nm and the injection amount was 10 μL.The relative correction factors(fa/b)was calculated for the other four components with uridine as an internal standard.The content of 5 ingredients in 10 batches of Periplaneta americana was determined by QAMS.Results were compared with those of external standard method(ESM).Results Five nucleosides showed good linear relationships in their own ranges(r＞0.999 5),and the average recoveries ranged from 97.0%to 100.8%.The relative correction factors of uracil,hypoxanthine,inosine and guanosine were 0.908 0,1.005 3,1.969 5 and 1.303 4,respectively.Conclusion The established method is accurate and stable.It can provide theoretical reference for the quality control of Periplaneta americana.

Objective:To investigate the effects of psychological stress on odour preference choices of mice and the related neural mechanisms.Methods:C57BL/6 male mice were randomly divided into control group and stress group.An unpredictable mild stress(UMS)model was established in the stress group using mild stress stimuli like fasting,restraint,and circadian rhythm disruption combined with open field tests.Then,the preferences for food extract odour and female urine odour was examined in control and UMS male mice.The specific brain regions activated during dual odour preference tests in UMS mice were identified by the expression of the neuronal activity-related c-Fos.Further,chemogenetic manipulation was used to validate key brain areas influencing UMS mice's odour preferences.Results:Control mice showed no clear preference for either odour,while UMS mice demonstrated a significant preference for fe-male urine.During the dual odour preference test,an increase in c-Fos positive neurons is observed in the medial pre-optic area(MPOA)and posterior dorsal part of medial amygdala(MePD)of UMS mice.Activating MePD resulted in male mice preferring female urine odour,while inhibiting MePD reduced this preference.The manipulation of MPOA did not affect the outcome of the dual-choice odour preference test.Conclusion:UMS male mice has a significant prefer-ence for female urine odour,and MePD is a key brain region regulating this behavior.

Objective:To investigate the effects of psychological stress on odour preference choices of mice and the related neural mechanisms.Methods:C57BL/6 male mice were randomly divided into control group and stress group.An unpredictable mild stress(UMS)model was established in the stress group using mild stress stimuli like fasting,restraint,and circadian rhythm disruption combined with open field tests.Then,the preferences for food extract odour and female urine odour was examined in control and UMS male mice.The specific brain regions activated during dual odour preference tests in UMS mice were identified by the expression of the neuronal activity-related c-Fos.Further,chemogenetic manipulation was used to validate key brain areas influencing UMS mice's odour preferences.Results:Control mice showed no clear preference for either odour,while UMS mice demonstrated a significant preference for fe-male urine.During the dual odour preference test,an increase in c-Fos positive neurons is observed in the medial pre-optic area(MPOA)and posterior dorsal part of medial amygdala(MePD)of UMS mice.Activating MePD resulted in male mice preferring female urine odour,while inhibiting MePD reduced this preference.The manipulation of MPOA did not affect the outcome of the dual-choice odour preference test.Conclusion:UMS male mice has a significant prefer-ence for female urine odour,and MePD is a key brain region regulating this behavior.

T cell infiltration and proliferation in tumor tissues are the main factors that significantly affect the therapeutic outcomes of cancer immunotherapy. Emerging evidence has shown that interferon-gamma (IFNγ) could enhance CXCL9 secretion from macrophages to recruit T cells, but Siglec15 expressed on TAMs can attenuate T cell proliferation. Therefore, targeted regulation of macrophage function could be a promising strategy to enhance cancer immunotherapy via concurrently promoting the infiltration and proliferation of T cells in tumor tissues. We herein developed reduction-responsive nanoparticles (NPs) made with poly (disulfide amide) (PDSA) and lipid-poly (ethylene glycol) (lipid-PEG) for systemic delivery of Siglec15 siRNA (siSiglec15) and IFNγ for enhanced cancer immunotherapy. After intravenous administration, these cargo-loaded could highly accumulate in the tumor tissues and be efficiently internalized by tumor-associated macrophages (TAMs). With the highly concentrated glutathione (GSH) in the cytoplasm to destroy the nanostructure, the loaded IFNγ and siSiglec15 could be rapidly released, which could respectively repolarize macrophage phenotype to enhance CXCL9 secretion for T cell infiltration and silence Siglec15 expression to promote T cell proliferation, leading to significant inhibition of hepatocellular carcinoma (HCC) growth when combining with the immune checkpoint inhibitor. The strategy developed herein could be used as an effective tool to enhance cancer immunotherapy.