Objective:To analyze the epidemiological and clinical characteristics of respiratory pathogens in China.Methods:This study was a cross-sectional study, which encompassed 19 core units of the clinical pathogen network and established a three-tiered clinical pathogen surveillance system. Thirty respiratory samples were collected every two weeks from various units from January to December 2024, and the clinical and pathogen diagnostic information were gathered. A total of 11 864 samples were tested using this system. The tier-1 clinical pathogen surveillance system covered influenza A virus (Flu-A), influenza B virus (Flu-B), respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The tier-2 clinical pathogen surveillance system focused on 18 key respiratory pathogens. The tier-3 clinical pathogen surveillance system further clarified whether any emerging infectious diseases had occurred.Results:The tier-1 clinical pathogen surveillance system showed Flu-A predominated in December, Flu-B predominated in January, SARS-CoV-2 peaked in March and August, whereas RSV circulated sporadically throughout the year. Geographic trends were broadly consistent across the seven major regions, although Flu-A detection in December was notably higher in Northeast China (48.1%(111/231)) and East China (36.2%(148/409)), and RSV detection was concentrated in the Northwest and South China from January to March. Data from the tier-2 clinical pathogen surveillance system indicated that Streptococcus pneumoniae, Mycoplasma pneumoniae, rhinovirus, and adenovirus were detected year-round, of these, Streptococcus pneumoniae and rhinovirus showed elevated positive detection rates from August to September, while adenovirus peaked in January. Legionella pneumophila was not detected throughout the year, and other pathogens fluctuated throughout the year without a consistent pattern. The predominant etiologic agents of pediatric pneumonia were Mycoplasma pneumoniae (35.0%(105/300)), rhinovirus (25.7%(77/300)), and adenovirus (17.3%(52/300)), whereas adult pneumonia was mainly caused by Streptococcus pneumoniae (10.5%(29/277)), Staphylococcus aureus (6.9%(19/277)), Mycoplasma pneumoniae (6.9%(19/277)), and Flu-A (6.1%(17/277)). The tier-3 clinical pathogen surveillance system did not identify any emerging respiratory pathogens. Conclusion:Respiratory pathogens in China in 2024 exhibit distinct temporal and spatial distribution patterns and vary among different populations.

Objective:To analyze the epidemiological and clinical characteristics of respiratory pathogens in China.Methods:This study was a cross-sectional study, which encompassed 19 core units of the clinical pathogen network and established a three-tiered clinical pathogen surveillance system. Thirty respiratory samples were collected every two weeks from various units from January to December 2024, and the clinical and pathogen diagnostic information were gathered. A total of 11 864 samples were tested using this system. The tier-1 clinical pathogen surveillance system covered influenza A virus (Flu-A), influenza B virus (Flu-B), respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The tier-2 clinical pathogen surveillance system focused on 18 key respiratory pathogens. The tier-3 clinical pathogen surveillance system further clarified whether any emerging infectious diseases had occurred.Results:The tier-1 clinical pathogen surveillance system showed Flu-A predominated in December, Flu-B predominated in January, SARS-CoV-2 peaked in March and August, whereas RSV circulated sporadically throughout the year. Geographic trends were broadly consistent across the seven major regions, although Flu-A detection in December was notably higher in Northeast China (48.1%(111/231)) and East China (36.2%(148/409)), and RSV detection was concentrated in the Northwest and South China from January to March. Data from the tier-2 clinical pathogen surveillance system indicated that Streptococcus pneumoniae, Mycoplasma pneumoniae, rhinovirus, and adenovirus were detected year-round, of these, Streptococcus pneumoniae and rhinovirus showed elevated positive detection rates from August to September, while adenovirus peaked in January. Legionella pneumophila was not detected throughout the year, and other pathogens fluctuated throughout the year without a consistent pattern. The predominant etiologic agents of pediatric pneumonia were Mycoplasma pneumoniae (35.0%(105/300)), rhinovirus (25.7%(77/300)), and adenovirus (17.3%(52/300)), whereas adult pneumonia was mainly caused by Streptococcus pneumoniae (10.5%(29/277)), Staphylococcus aureus (6.9%(19/277)), Mycoplasma pneumoniae (6.9%(19/277)), and Flu-A (6.1%(17/277)). The tier-3 clinical pathogen surveillance system did not identify any emerging respiratory pathogens. Conclusion:Respiratory pathogens in China in 2024 exhibit distinct temporal and spatial distribution patterns and vary among different populations.

Background: Aging leads to sarcopenia, which is characterized by reduced muscle mass and strength. Many factors, including altered muscle protein turnover, diminished neuromuscular function, hormonal changes, systemic inflammation, and the structure and composition of muscle fibers, play a crucial role in age-related muscle decline. This study explored differences in muscle fiber types contributing to overall muscle function decline in aging, focusing on individuals with hip fractures from falls. Methods: A pilot study at Chungnam National University Hospital collected muscle biopsies from hip fracture patients aged 20 to 80 undergoing surgical treatment. Muscle biopsies from the vastus lateralis and gluteus maximus were obtained during hip arthroplasty or internal fixation. Handgrip strength, calf and thigh circumference, and bone mineral density were evaluated in individuals with hip fractures from falls. We analyzed the relationships between each clinical characteristic and muscle fiber type. Results: In total, 26 participants (mean age 67.9 years, 69.2% male) were included in this study. The prevalence of sarcopenia was 53.8%, and that of femoral and lumbar osteoporosis was 19.2% and 11.5%, respectively. Vastus lateralis analysis revealed an age-related decrease in type IIx fibers, a higher proportion of type IIa fibers in women, and an association between handgrip strength and type IIx fibers in men. The gluteus maximus showed no significant correlations with clinical parameters. Conclusion This study identified complex associations between age, sex, handgrip strength, and muscle fiber composition in hip fracture patients, offering insights crucial for targeted interventions combating age-related muscle decline and improving musculoskeletal health.

Studies have suggested that the nucleus accumbens (NAc) is implicated in the pathophysiology of major depression; however, the regulatory strategy that targets the NAc to achieve an exclusive and outstanding anti-depression benefit has not been elucidated. Here, we identified a specific reduction of cyclic adenosine monophosphate (cAMP) in the subset of dopamine D1 receptor medium spiny neurons (D1-MSNs) in the NAc that promoted stress susceptibility, while the stimulation of cAMP production in NAc D1-MSNs efficiently rescued depression-like behaviors. Ketamine treatment enhanced cAMP both in D1-MSNs and dopamine D2 receptor medium spiny neurons (D2-MSNs) of depressed mice, however, the rapid antidepressant effect of ketamine solely depended on elevating cAMP in NAc D1-MSNs. We discovered that a higher dose of crocin markedly increased cAMP in the NAc and consistently relieved depression 24 h after oral administration, but not a lower dose. The fast onset property of crocin was verified through multicenter studies. Moreover, crocin specifically targeted at D1-MSN cAMP signaling in the NAc to relieve depression and had no effect on D2-MSN. These findings characterize a new strategy to achieve an exclusive and outstanding anti-depression benefit by elevating cAMP in D1-MSNs in the NAc, and provide a potential rapid antidepressant drug candidate, crocin.

Objective To construct mouse BaF3-FIP1L1-PDGFRA(F/P),BaF3-F/P-T674I and BAF3-F/P-D842V pre-B cell strains which stably express F/P fusion protein and its T674I and D842V mutants in order to e-valuate their activity by checking their responses to tyrosine kinase inhibitors(TKIs).Methods Lentivirus infected technique was used to transfect the target gene into BaF3 cells.RT-qPCR was used to detect mRNA expression,and CCK-8 method was used to detect the inhibitory effect of TKIs on the proliferation of stable cell strains.Results The constructed BaF3-F/P,BaF3-F/P-T674I and BAF3-F/P-D842V cell strains all transcripted FIP1L1 and PDGFRA mRNA.They exhibited malignant phenotypic characteristics of proliferation independent of IL-3 and sen-sitivity to corresponding TKIs.Conclusions The pre-B-cell strains stably expressing F/P and its T674I and D842V mutants are successfully constructed,which provide a good cell model for the development of compounds targeting at those molecules.

BACKGROUND:In the initial stage of multiple sclerosis,central immune cells activate and release a large number of inflammatory factors,causing white matter demyelination and even involving gray matter neurons.The equilibrium of differentiation between different subsets of CD4+ T cells plays an important role in the progression of experimental autoimmune encephalomyelitis.The previous results of the research group showed that the active ingredient astragalus glycoprotein in astragalus can regulate the immune response in experimental autoimmune encephalomyelitis mice,and whether it has a regulatory effect on the differentiation of T cell subsets has not been determined. OBJECTIVE:To explore the therapeutic effects and immune regulatory mechanisms of astragaloside IV on experimental autoimmune encephalomyelitis mice. METHODS:Female C57BL/6 mice were divided into the normal control group,experimental autoimmune encephalomyelitis disease model group,and astragaloside IV treatment group(n=8 per group).Myelin oligodendrocyte glycoprotein peptides 35-55 were used for experimental autoimmune encephalomyelitis model induction in the last two groups.On day 10 to 28 after immunization,the astragaloside IV treatment group was treated with 40 mg/kg per day astragaloside IV intragastrically.Body weight and clinical scores of mice in each group were recorded from the immunization day to the 28th day.On the 28th day after immunization,the mouse spinal cord was taken and made into frozen sections for hematoxylin-eosin staining and Lux fast blue staining to observe pathological changes in the spinal cord.Percentage of splenic T cell subsets was detected using flow cytometry.Western blot assay was used to determine the protein expression of interferon-γ,interleukin-17 and interleukin-6 in the spinal cord.Levels of interferon-γ,interleukin-17,interleukin-6 and interleukin-4 in supernatants of cultured splenocytes were determined by ELISA. RESULTS AND CONCLUSION:(1)Compared with the experimental autoimmune encephalomyelitis disease model group,astragaloside IV could reduce the degree of weight loss in experimental autoimmune encephalomyelitis mice(P<0.05),ameliorate clinical symptoms(P<0.05),inhibit the infiltration of inflammatory cells and alleviate myelin loss(P<0.01,P<0.05).(2)Compared with the experimental autoimmune encephalomyelitis disease model group,astragaloside IV could inhibit the proportion of CD4+T cell subsets expressing interferon-γ(P<0.001)and interleukin-17(P<0.001),but increase percentages of CD4+ interleukin-10+(P<0.001)and CD4+ transforming growth factor-β+(P<0.01)T cell subsets.(3)Astragaloside IV could inhibit the expression of interferon-γ(P<0.05,P<0.01),interleukin-17(P<0.05,P<0.05),and interleukin-6(P<0.05,P<0.05)in the spinal cord and spleen,and up-regulate the expression of interleukin-4(P<0.01)in spleen.(4)These findings confirm that astragaloside IV alleviates clinical symptoms in experimental autoimmune encephalomyelitis mice,which may be related to regulating the splenic T cell subsets,therefore,inhibiting the infiltration of inflammatory cells into the center and reducing the demyelination.

BACKGROUND:Astrocytes play an important role in the pathology of central nervous system diseases.The phenotypic and functional changes in astrocytes suggest that it may be an effective therapeutic target for central nervous system diseases.Our previous studies have confirmed that astragaloside can inhibit the lipopolysaccharide-induced astrocyte inflammatory response.Whether astragaloside can regulate the phenotype and function of astrocytes through Notch-1 and its downstream signaling pathway remains unclear. OBJECTIVE:To explore the effect of astragaloside on astrocyte activation and inflammatory response induced by inflammation and its possible mechanism. METHODS:Cerebral cortex astrocytes derived from neonatal C57BL/6 mouse were cultured in vitro.CCK-8 assay was used to determine the optimum concentration of astragaloside and Notch active inhibitor DAPT.The astrocytes were divided into five groups:PBS group,lipopolysaccharide group,lipopolysaccharide + astragaloside group,lipopolysaccharide + DAPT group and lipopolysaccharide + DAPT + astragaloside group.The secretion level of inflammatory factors was detected by ELISA,and the level of nitric oxide was detected by Griess method.The astrocytes and splenic mononuclear cells were co-cultured in Transwell chamber to observe the migration of CD4T cells.The expression of astrocyte activation marker GFAP,A1 marker C3 and A2 marker S100A10 as well as Notch 1 and Jag-1 was detected by immunofluorescence staining.The expressions of CFB,C3,S100A10,PTX3,Notch-1,Jag-1,and Hes were detected by western blot assay. RESULTS AND CONCLUSION:(1)According to the results of CCK8 assay,the final concentration of astragaloside was selected as 25 μmol/L and the final concentration of DAPT was 50 μmol/L for follow-up experiments.(2)Compared with PBS group,interleukin-6,interleukin-12 and nitric oxide secretion levels in the lipopolysaccharide group were significantly increased(P<0.05,P<0.05,P<0.01).Compared with the lipopolysaccharide group,interleukin-6(all P<0.05),interleukin-12(P>0.05,P<0.05,P<0.05)and nitric oxide(P<0.05,P<0.01,P<0.01)secretion significantly reduced in the lipopolysaccharide + astragaloside group,lipopolysaccharide +DAPT group,lipopolysaccharide + DAPT + astragaloside group.(3)Compared with the PBS group,the expression of GFAP that is the marker of activated astrocytes and the migration of CD4 T cells were significantly increased in the lipopolysaccharide group(P<0.01).Compared with the lipopolysaccharide group,astrocyte activation was significantly inhibited and CD4 T cell migration was significantly reduced in the lipopolysaccharide + astragaloside,lipopolysaccharide +DAPT,lipopolysaccharide + DAPT + astragaloside group(P<0.05,P<0.05,P<0.01).(4)Compared with the PBS group,the expressions of A1 markers C3 and CFB in the lipopolysaccharide group were increased(P<0.01,P<0.05),and the expressions of A2 markers S100A10 and PTX3 were decreased(P<0.01,P<0.05).Compared with the lipopolysaccharide group,C3(all P<0.01)and CFB(both P<0.05)were significantly reduced and S100A10(all P<0.01)and PTX3(P<0.05,P<0.05 and P>0.05)were increased in the lipopolysaccharide + astragaloside,lipopolysaccharide +DAPT,lipopolysaccharide + DAPT + astragaloside group.(5)Compared with the PBS group,the expressions of Jag-1,Notch-1 and Hes in the lipopolysaccharide group were significantly increased(all P<0.01).Compared with the lipopolysaccharide group,the expressions of Jag-1(all P<0.01),Notch-1(all P<0.01)and Hes(P<0.05,P<0.01 and P<0.01)were significantly reduced in the lipopolysaccharide + astragaloside,lipopolysaccharide +DAPT,lipopolysaccharide + DAPT + astragaloside group.(6)The results indicate that astragaloside can promote the transformation of astrocytes from A1 to A2 by regulating Notch-1 signaling pathway,reduce the secretion of inflammatory factors and the migration of CD4 T cells,and thus inhibit astrocyte activation and inflammatory response.

ObjectiveTo observe the effect of Buyang Huanwutang in treating diabetic peripheral neuropathy （DPN） by inhibiting pyroptosis through AMP-activated protein kinase （AMPK）/UNC-51-like kinase 1 （ULK1） mitophagy pathway. MethodSixty male SPF SD rats （6-7 weeks old） were used in animal experiments and numbered according to their body mass. They were then randomly divided into four groups by computer： normal group， model group， α-lipoic acid group（60 mg·kg^-1）， and Buyang Huanwutang group（15 g·kg^-1）， with 15 rats in each group. The diabetic model was established by injection of streptozocin （STZ）. After successful modeling， the α-lipoic acid group and the Buyang Huanwutang group were given corresponding drugs， and the normal group and the model group were given normal saline. Sensory nerve conduction velocity （SNCV） and paw withdrawal threshold （PWT） were measured at the end of administration for 12 weeks. Immunohistochemistry and Western blot were used to detect the expression of phosphorylated AMP activated protein kinase （p-AMPK）， phosphorylated UNC-51-like kinase 1 （p-ULK1）， protein involved in microtubule-associated protein 1 light chain 3 （LC3）， selective autophagy receptors （p62/SQSTM1）， Beclin1， NOD receptor protein structure domain-related proteins 3 （NLRP3）， Caspase-1 （Caspase-1）， and interleukin-1 beta （IL-1β） in dorsal root ganglia （DRG）. Immunofluorescence was used to detect the expression of the N-terminal gasdermin D （N-GSDMD）. ResultCompared with those in the normal group， rats in the model group had increased fasting blood glucose （P<0.01） and significantly reduced SNCV， PWT （P<0.01）， LC3Ⅱ/LC3Ⅰ， Beclin1， p-AMPK/AMPK， and p-ULK1/ULK1 （P<0.01）. In addition， p62， NLRP3， N-GSDMD/GSDMD， IL-1β， and cleaved Caspase-1/Caspase-1 were significantly increased （P<0.01）. Compared with those in the model group， SNCV and PWT were increased （P<0.01） in each administration group， and LC3Ⅱ/LC3Ⅰ， Beclin1， p-AMPK/AMPK， and p-ULK1/ULK1 were significantly increased （P<0.05， P<0.01）. p62， N-GSDMD/GSDMD， cleaved Caspase-1/Caspase-1， NLRP3， and IL-1β decreased （P<0.05， P<0.01）. Compared with the α-lipoic acid group， the Buyang Huanwutang group had significantly increased SNCV， PWT （P<0.05）， LC3Ⅱ/LC3Ⅰ， and p-ULK1/ULK1 （P<0.05） and significantly decreased NLRP3 and N-GSDMD/GSDMD （P<0.05）. ConclusionBuyang Huanwutang regulates mitophagy and inhibits pyroptosis through the AMPK/ULK1 pathway to prevent and treat DPN， and its therapeutic effect may be better than α-lipoic acid.

Objective:To isolate and identify SARS-CoV-2 epidemic strains and analyze the sequence characteristics of the virus strains following serial passages.Methods:Eleven nasopharyngeal swabs positive for SARS-CoV-2 antigen were collected from December 2022. Quantitative real-time PCR was used to detect SARS-CoV-2 nucleic acid, and positive specimens were inoculated onto Vero cells for virus isolation. The isolated strains were identified by Western blot and indirect immunofluorescence assay. The morphology of the isolated strains was observed using transmission electron microscopy. Nucleic acid was extracted from the isolates and passaged viruses for further sequencing and analysis.Results:All 11 specimens tested positive for SARS-CoV-2 using quantitative real-time PCR. SARS-CoV-2 strains were successfully isolated from seven specimens, and could be adaptively cultured, passaged, and expanded on Vero cells, achieving a peak titer exceeding 10 6.25 50% cell culture infectious dose (CCID 50)/ml. Western blot and indirect immunofluorescence results showed that the isolates could be specifically recognized by monoclonal antibodies and convalescent serum against SARS-CoV-2. Transmission electron microscopy revealed oval-shaped viral particles with diameters of approximately 100 nm. Next-generation sequencing of the viral isolates demonstrated a sequence homology greater than 99.50% with the Wuhan-Hu-1 reference strain (NC_045512) and 99.98% among the seven isolated strains, and all of the isolates belonged to the Omicron BF.7 variant. Sequence analysis after continuous passage and plaque purification of the BJ-NVSI-20230005 isolate showed that compared with passages 1-3, passages 4-6 had one nucleotide site mutation (C→T) in the ORF1ab gene and a deletion of 3 bp in the E gene, which resulted in a change from leucine to phenylalanine and the deletion of valine, respectively. Polymorphisms were observed in the sequences of plaque-purified clones. Conclusions:The seven successfully isolated SARS-CoV-2 strains all belong to the SARS-CoV-2 BF.7 variant, which is consistent with the prevalence trend in mainland China in December 2022.

Objective:To explore mechanism of Fasudil reducing Aβ1-42 induced BV2 cell injury based on NLRP3 inflamma-some.Methods:BV2 cells were divided into:normal control group,Aβ stimulation group,Aβ+Fasudil intervention group,Aβ+MCC950(NLRP3 inhibitor)intervention group.Cell morphology was observed under microscope.Cell activity was determined of by CCK8.NO release was measured by Griess.NLRP3,caspase 1 and IL-18 expressions were detected by immunofluorescence staining.NLRP3,ASC,caspase 1,IL-1β and IL-18 expressions were detected by Western blot.Results:Compared with normal control group,BV2 cells in Aβ stimulation group were activated and showed amoeba-like shape,cell activity was decreased,NO production was increased,NLRP3,ASC,caspase 1,IL-1β and IL-18 expressions were increased.Fasudil intervention and MCC950 intervention inhibited cell injury induced by Aβ1-42 in which BV2 cell morphology tended to be normal,cell activity was increased,while produc-tion of NO was reduced,and NLRP3,ASC,caspase 1,IL-1β and IL-18 expressions were down-regulated,there was no significant difference between Fasudil intervention group and MCC950 intervention group.Conclusion:Fasudil may alleviate Aβ1-42 induced BV2 cell injury and inflammatory reaction by inhibiting NLRP3 inflammasome activation.