GPR126, also known as ADGRG6, is one of the most deeply studied aGPCRs. Initially, GPR126 was thought to be a receptor associated with muscle development and was primarily expressed in the muscular and skeletal systems. With the deepening of research, it was found that GPR126 is expressed in multiple mammalian tissues and organs, and is involved in many biological processes such as embryonic development, nervous system development, and extracellular matrix interactions. Compared with other aGPCRs proteins, GPR126 has a longer N-terminal domain, which can bind to ligands one-to-one and one-to-many. Its N-terminus contains five domains, a CUB (complement C1r/C1s, Uegf, Bmp1) domain, a PTX (Pentraxin) domain, a SEA (Sperm protein, Enterokinase, and Agrin) domain, a hormone binding (HormR) domain, and a conserved GAIN domain. The GAIN domain has a self-shearing function, which is essential for the maturation, stability, transport and function of aGPCRs. Different SEA domains constitute different GPR126 isomers, which can regulate the activation and closure of downstream signaling pathways through conformational changes. GPR126 has a typical aGPCRs seven-transmembrane helical structure, which can be coupled to Gs and Gi, causing cAMP to up- or down-regulation, mediating transmembrane signaling and participating in the regulation of cell proliferation, differentiation and migration. GPR126 is activated in a tethered-stalk peptide agonism or orthosteric agonism, which is mainly manifested by self-proteolysis or conformational changes in the GAIN domain, which mediates the rapid activation or closure of downstream pathways by tethered agonists. In addition to the tethered short stem peptide activation mode, GPR126 also has another allosteric agonism or tunable agonism mode, which is specifically expressed as the GAIN domain does not have self-shearing function in the physiological state, NTF and CTF always maintain the binding state, and the NTF binds to the ligand to cause conformational changes of the receptor, which somehow transmits signals to the GAIN domain in a spatial structure. The GAIN domain can cause the 7TM domain to produce an activated or inhibited signal for signal transduction, For example, type IV collagen interacts with the CUB and PTX domains of GPR126 to activate GPR126 downstream signal transduction. GPR126 has homology of 51.6%-86.9% among different species, with 10 conserved regions between different species, which can be traced back to the oldest metazoans as well as unicellular animals.In terms of diseases, GPR126 dysfunction involves the pathological process of bone, myelin, embryo and other related diseases, and is also closely related to the occurrence and development of malignant tumors such as breast cancer and colon cancer. However, the biological function of GPR126 in various diseases and its potential as a therapeutic target still needs further research. This paper focuses on the structure, interspecies differences and conservatism, signal transduction and biological functions of GPR126, which provides ideas and references for future research on GPR126.

Aim To investigate the role of metabolites of eicosapentaenoic acid (EPA) in promoting the transdifferentiation of pancreatic α cells to β cells. Methods Male C57BL/6J mice were injected intraperitoneally with 60 mg/kg streptozocin (STZ) for five consecutive days to establish a type 1 diabetes (T1DM) mouse model. After two weeks, they were randomly divided into model groups and 97% EPA diet intervention group, 75% fish oil (50% EPA +25% DHA) diet intervention group, and random blood glucose was detected every week; after the model expired, the regeneration of pancreatic β cells in mouse pancreas was observed by immunofluorescence staining. The islets of mice (obtained by crossing GCG

Objective To summarize the epidemiological and clinical features of infectious diseases of the central nervous system(CNS)by a single-center analysis.Methods A retrospective analysis was conducted on the data of 1247 cases of CNS infectious diseases diagnosed and treated in the First Medical Center of PLA General Hospital from 2001 to 2020.Results The data for this group of CNS infectious diseases by disease type in descending order of number of cases were viruses 743(59.6％),Mycobacterium tuberculosis 249(20.0％),other bacteria 150(12.0％),fungi 68(5.5％),parasites 18(1.4％),Treponema pallidum 18(1.4％)and rickettsia 1(0.1％).The number of cases increased by 177 cases(33.1％)in the latter 10 years compared to the previous 10 years(P<0.05).No significant difference in seasonal distribution pattern of data between disease types(P>0.05).Male to female ratio is 1.87︰1,mostly under 60 years of age.Viruses are more likely to infect students,most often at university/college level and above,farmers are overrepresented among bacteria and Mycobacterium tuberculosis,and more infections of Treponema pallidum in workers.CNS infectious diseases are characterized by fever,headache and signs of meningeal irritation,with the adductor nerve being the more commonly involved cranial nerve.Matagenomic next-generation sequencing improves clinical diagnostic capabilities.The median hospital days for CNS infectious diseases are 18.00(11.00,27.00)and median hospital costs are ￥29,500(￥16,000,￥59,200).The mortality rate from CNS infectious diseases is 1.6％.Conclusions The incidence of CNS infectious diseases is increasing last ten years,with complex clinical presentation,severe symptoms and poor prognosis.Early and accurate diagnosis and standardized clinical treatment can significantly reduce the morbidity and mortality rate and ease the burden of disease.

Objective To observe the therapeutic effect and mechanism of Astragaloside Ⅳ liposomes for influenza A virus infection in mice.Methods Fifty BALB/c mice were randomly divided into normal group(10 mice)and modeling group(40 mice).The modeling group mice were injected with A/PR/8/34(H1N1)influenza virus liquid via nasal drip.The modeling mice were randomly divided into model group,Oseltamivir group,and Astragaloside Ⅳ Liposomes high-and low-dose groups,with 10 mice in each group.The drug was administered by gavage two hours after infection for five days continuously.The appearance of the mice was observed,the body mass,survival condition and lung index as well as viral load in lung were assessed,pathological feature of lung tissue was observed by hematoxylin-eosin(HE)staining method,and mRNA expression levels of monocyte chemoattractant protein 1(MCP-1),macrophage inflammatory protein 1β(MIP-1β),and interferon γ(IFN-γ),CXC chemokine ligand 1(CXCL-1),interleukin(IL)-6,and IL-1β in lung tissues were detected by quantitative polymerase chain reaction(qPCR)method.Enzyme-linked immunosorbent assay(ELISA)was performed to detect the contents of granulocyte-macrophage colony-stimulating factor(GM-CSF)and regulated on activation normal T-cell expressed and secreted(RANTES)in mouse lung tissue.Results Compared with the normal group,mice in the model group showed significant decrease of body mass,shortened survival time(P＜0.001),significantly increased lung index(P＜0.001),significantly increased viral load in lung(P＜0.001),and significantly increased mRNA expression levels of MIP-1β,IFN-γ,CXCL-1,IL-6,IL-1β and MCP-1 in lung tissue(P＜0.05 or P＜0.001),and the structure destruction of lung tissue could be seen in pathology.Compared with the model group,mice in the Astragaloside Ⅳ liposomes high-dose group showed that the decrease in body mass was slowed down,the survival time and survival rate were higher(P＜0.05),and the lung index was significantly decreased(P＜0.05),the viral load in lung was decreased(P＜0.001)and the mRNA expression levels of MIP-1β,IFN-γ,CXCL-1,IL-6,IL-1β and MCP-1 in lung tissue were decreased,and the alveolar structure was relatively intact,and a little connective tissue hyperplasia was seen.Conclusion Astragaloside Ⅳ liposomes can improve the survival time and reduce the viral load of lung tissue in mice with influenza A virus infection,and its mechanism may be related to the inhibition of the expression of inflammatory factors,thus playing an antiviral role.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objective:To investigate two cases of rare pathogenic genes,initiation codon mutations in HBA2 gene,combined with Southeast Asian deletion and their family members to understand the relationship of HBA2:c.2T＞C and HBA2:c.2delT mutations with clinical phenotype.Methods:The peripheral blood of family members was obtained for blood cell analysis and capillary electrophoresis hemoglobin analysis.Gap-PCR and reverse dot blotting(RDB)were used to detect common types of mutations in α-thalassaemia gene.Sanger sequencing was used to analyze HBA1 and HBA2 gene sequence.Results:Two proband genotypes were identified as--SEA/αα with HBA2:c.2T＞C and--SEA/αα with HBA2:c.2delT.HBA2:c.2T＞C/WT and HBA2:c.2delT/WT was detected in family members.They all presented with microcytic hypochromic anemia.Conclusion:When HBA2:c.2T＞C and HBA2:c.2delT are heterozygous that can lead to static α-thalassemia phenotype,and when combined with mild α-thalassemia,they can lead to the clinical manifestations of hemoglobin H disease.This study provides a basis for genetic counseling.

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 understand the change in distribution and antimicrobial resistance of bacteria isolated from blood specimens of Hunan Province,and provide for the initial diagnosis and treatment of clinical bloodstream infection(BSI).Methods Data reported from member units of Hunan Province Antimicrobial Resistance Survei-llance System from 2012 to 2021 were collected.Bacterial antimicrobial resistance surveillance method was imple-mented according to the technical scheme of China Antimicrobial Resistance Surveillance System(CARSS).Bacteria from blood specimens and bacterial antimicrobial susceptibility testing results were analyzed by WHONET 5.6 soft-ware and SPSS 27.0 software.Results A total of 207 054 bacterial strains were isolated from blood specimens from member units in Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021,including 107 135(51.7％)Gram-positive bacteria and 99 919(48.3％)Gram-negative bacteria.There was no change in the top 6 pathogenic bacteria from 2012 to 2021,with Escherichia coli(n=51 537,24.9％)ranking first,followed by Staphylococcus epidermidis(n=29 115,14.1％),Staphylococcus aureus(n=17 402,8.4％),Klebsiella pneu-moniae(17 325,8.4％),Pseudomonas aeruginosa(n=4 010,1.9％)and Acinetobacter baumannii(n=3 598,1.7％).The detection rate of methicillin-resistant Staphylococcus aureus(MRSA)decreased from 30.3％in 2015 to 20.7％in 2021,while the detection rate of methicillin-resistant coagulase-negative Staphylococcus(MRCNS)showed an upward trend year by year(57.9％-66.8％).No Staphylococcus was found to be resistant to vancomy-cin,linezolid,and teicoplanin.Among Gram-negative bacteria,constituent ratios of Escherichia coli and Klebsiella pneumoniae were 43.9％-53.9％and 14.2％-19.5％,respectively,both showing an upward trend(both P＜0.001).Constituent ratios of Pseudomonas aeruginosa and Acinetobacter baumannii were 3.6％-5.1％and 3.0％-4.5％,respectively,both showing a downward trend year by year(both P＜0.001).From 2012 to 2021,resistance rates of Escherichia coli to imipenem and ertapenem were 1.0％-2.0％and 0.6％-1.1％,respectively;presenting a downward trend(P＜0.001).The resistant rates of Klebsiella pneumoniae to meropenem and ertapenem were 7.4％-13.7％and 4.8％-6.4％,respectively,presenting a downward trend(both P＜0.001).The resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenem antibiotics were 7.1％-15.6％and 34.7％-45.7％,respectively.The trend of resistance to carbapenem antibiotics was relatively stable,but has de-creased compared with 2012-2016.The resistance rates of Escherichia coli to the third-generation cephalosporins from 2012 to 2021 were 41.0％-65.4％,showing a downward trend year by year.Conclusion The constituent ra-tio of Gram-negative bacillus from blood specimens in Hunan Province has been increasing year by year,while the detection rate of carbapenem-resistant Gram-negative bacillus remained relatively stable in the past 5 years,and the detection rate of coagulase-negative Staphylococcus has shown a downward trend.

Objective To investigate changes in the distribution and antimicrobial resistance of bacteria isolated from cerebrospinal fluid(CSF)specimens in Hunan Province,and provide reference for correct clinical diagnosis and rational antimicrobial use.Methods Data reported by member units of Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021 were collected according to China Antimicrobial Resistance Surveillance Sys-tem(CARSS)technical scheme.Data of bacteria isolated from CSF specimens and antimicrobial susceptibility tes-ting results were analyzed with WHONET 5.6 and SPSS 20.0 software.Results A total of 11 837 bacterial strains were isolated from CSF specimens from member units of Hunan Province Antimicrobial Resistance Surveillance Sys-tem from 2012 to 2021.The top 5 strains were coagulase-negative Staphylococcus(n=6 397,54.0％),Acineto-bacter baumannii(n=764,6.5％),Staphylococcus aureus(n=606,5.1％),Enterococcus faecium(n=465,3.9％),and Escherichia coli(n=447,3.8％).The detection rates of methicillin-resistant coagulase-negative Staphyloco-ccus(MRCNS)and methicillin-resistant Staphylococcus aureus(MRSA)were 58.9％-66.3％and 34.4％-62.1％,respectively.No Staphylococcus spp.were found to be resistant to vancomycin,linezolid,and teicoplanin.The de-tection rate of Enterococcus faecium was higher than that of Enterococcus faecalis,and the resistance rates of En-terococcus f aecium to penicillin,ampicillin,high concentration streptomycin and levofloxacin were all higher than those of Enterococcus faecalis(all P=0.001).Resistance rate of Streptococcus pneumoniae to penicillin was 85.0％,at a high level.Resistance rate of Escherichia coli to ceftriaxone was＞60％,while resistance rates to enzyme inhibitors and carbapenem antibiotics were low.Resistance rate of Klebsiella pneumoniae to ceftriaxone was＞60％,to en-zyme inhibitors piperacillin/tazobactam and cefoperazone/sulbactam was＞30％,to carbapenem imipenem and me-ropenem was about 30％.Resistance rates of Acinetobacter baumannii to most tested antimicrobial agents were＞60％,to imipenem and meropenem were 59.0％-79.4％,to polymyxin B was low.Conclusion Among the bac-teria isolated from CSF specimens,coagulase-negative Staphylococcus accounts for the largest proportion,and the overall resistance of pathogenic bacteria is relatively serious.Bacterial antimicrobial resistance surveillance is very important for the effective treatment of central nerve system infection.

Objective To explore characteristics of co-infection of Chlamydia pneumoniae(Cpn)and severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),and identify their effect on SARS-CoV-2-induced inflammatory response.Methods Patients with coronavirus disease 2019(COVID-19)who received treatment in a hospital in Chenzhou City from December 20,2022 to February 20,2023 were selected.According to the severity of COVID-19,severe and critical cases were classified as the severe symptom group,while mild and moderate cases were classified as the mild symptom group.Meanwhile,according to the age of patients(≥18 years old as adults,＜18 years old as juveniles),they were divided into the adult severe symptom group,adult mild symptom group,juvenile severe symptom group,and juvenile mild symptom group.Propensity score was adopted to match age,gender,and under-lying diseases of patients in severe symptom and mild symptom group in a 1∶1 ratio.Bronchoalveolar lavage fluid(BALF),throat swabs,and serum specimens of patients were collected.Cpn IgG/IgM antibody was detected by enzyme-linked immunosorbent assay(ELISA),levels of 12 common cytokines(including interleukin-8[IL-8])in BALF were detected by flow cytometry,differences among groups were compared.Results A total of 102 patients were included,with 61 severe and critical(severe symptom)patients,as well as 41 mild and moderate(mild symp-tom)patients.There were 71 patients aged ≥18 years and 31 juvenile patients aged＜18 years.There were 39 pa-tients in the adult severe symptom group and 32 in the adult mild symptom group,and 30 pairs were successfully matched through propensity score analysis.There were 22 patients in the juvenile severe symptom group and 9 in the juvenile mild symptom group,and 8 pairs were successfully matched through propensity score analysis.Among COVID-19 patients,the positive rates of Cpn IgG and IgM were 36.27％(n=37)and 8.82％(n=9),respective-ly,with 1 case positive for both Cpn IgG and IgM.The level of interferon(IFN)-α in serum specimens from adult patients with severe symptom combined with positive Cpn IgG was higher than that of IgG negative patients(P=0.037).There was no statistically significant difference in the levels of other cytokines in BALF and serum speci-mens between the two groups of patients(all P＞0.05).The levels of IL-8 and IL-17 in serum specimens of patients with positive Cpn IgG in the adult mild symptom group were both higher than those in Cpn IgG negative patients(both P＜0.05).The levels of IL-8 in both BALF and serum specimens from Cpn IgM positivity patients in the ju-venile mild symptom group were higher than those from patients with negative Cpn IgM(both P＜0.05).Logistic regression analysis results showed that Cpn IgG and IgM positivity were not risk factors for the development of se-vere COVID-19.Conclusion Combined Cpn infection is not a risk factor for the development of severe symptom in COVID-19 patients,and Cpn infection has limited impact on the secretion of inflammatory factors caused by SARS-CoV-2.