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.

BACKGROUND:Osteosarcoma has a complex pathogenesis and a poor prognosis.While advancements in medical technology have led to some improvements in the 5-year survival rate,substantial progress in its treatment has not yet been achieved. OBJECTIVE:To screen key molecular markers in osteosarcoma,analyze their relationship with osteosarcoma treatment drugs,and explore the potential disease mechanisms of osteosarcoma at the molecular level. METHODS:GSE99671 and GSE284259(miRNA)datasets were obtained from the Gene Expression Omnibus database.Differential gene expression analysis and Weighted Gene Co-expression Network Analysis(WGCNA)on GSE99671 were performed.Functional enrichment analysis was conducted using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes separately for the differentially expressed genes and the module genes with the highest positive correlation to the disease.The intersection of these module genes and differentially expressed genes was taken as key genes.A Protein-Protein Interaction network was constructed,and correlation analysis on the key genes was performed using CytoScape software,and hub genes were identified.Hub genes were externally validated using the GSE28425 dataset and text validation was conducted.The drug sensitivity of hub genes was analyzed using the CellMiner database,with a threshold of absolute value of correlation coefficient|R|>0.3 and P<0.05. RESULTS AND CONCLUSION:(1)Differential gene expression analysis identified 529 differentially expressed genes,comprising 177 upregulated and 352 downregulated genes.WGCNA analysis yielded a total of 592 genes with the highest correlation to osteosarcoma.(2)Gene Ontology enrichment results indicated that the development of osteosarcoma may be associated with extracellular matrix,bone cell differentiation and development,human immune regulation,and collagen synthesis and degradation.Kyoto Encyclopedia of Genes and Genomes enrichment results showed the involvement of pathways such as PI3K-Akt signaling pathway,focal adhesion signaling pathway,and immune response in the onset of osteosarcoma.(3)The intersection analysis revealed a total of 59 key genes.Through Protein-Protein Interaction network analysis,8 hub genes were selected,which were LUM,PLOD1,PLOD2,MMP14,COL11A1,THBS2,LEPRE1,and TGFB1,all of which were upregulated.(4)External validation revealed significantly downregulated miRNAs that regulate the hub genes,with hsa-miR-144-3p and hsa-miR-150-5p showing the most significant downregulation.Text validation results demonstrated that the expression of hub genes was consistent with previous research.(5)Drug sensitivity analysis indicated a negative correlation between the activity of methotrexate,6-mercaptopurine,and pazopanib with the mRNA expression of PLOD1,PLOD2,and MMP14.Moreover,zoledronic acid and lapatinib showed a positive correlation with the mRNA expression of PLOD1,LUM,MMP14,PLOD2,and TGFB1.This suggests that zoledronic acid and lapatinib may be potential therapeutic drugs for osteosarcoma,but further validation is required through additional basic experiments and clinical studies.

Biosensor analysis technology is a kind of technology with high specificity that can convert biological reactions into optical and electrical signals. In the development of drugs for Alzheimer's disease (AD), according to different disease hypotheses and targets, this technology plays an important role in confirming targets and screening active compounds. This paper briefly describes the pathogenesis of AD and the current situation of therapeutic drugs, introduces three biosensor analysis techniques commonly used in the discovery of AD drugs, such as surface plasmon resonance (SPR), biolayer interferometry (BLI) and fluorescence analysis technology, explains its basic principle and application progress, and summarizes their advantages and limitations respectively.

Objective To observe the intervention effect of hypericin(HYP)on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced Parkinson's disease(PD)mice model and its mechanism.Methods Thirty C57BL/6 mice were randomly divided into normal,model and experimental groups with 10 mice per group.PD mouse model was established after 7 days of intraperitoneal injection of MPTP,and drug intervention was carried out from the first day of modeling.Normal group and model group were intraperitoneally injected with 500 μL·kg·d-1 0.9％NaCl.The experimental group was intraperitoneally injected with 25 mg·kg·d-1 HYP.The three groups of rats were given the drug once each time for 14 days.The expression levels of tyrosine hydroxylase(TH),Nod-like receptor thermal protein domain protein 3(NLRP3)and ionized calcium binding adapter molecule 1(Iba1)in the striatum of nigra were detected by Western blot.Results The climbing time of normal,model and experimental groups was(5.35±0.43),(9.71±1.19)and(8.07±0.34)s;suspension scores were(2.92±0.15),(1.38±0.28)and(1.96±0.28)points;the relative expression levels of TH protein were 1.04±0.06,0.51±0.09 and 0.75±0.07;the relative expression levels of NLRP3 protein were 0.51±0.03,1.00±0.04 and 0.77±0.06;the relative expression levels of Iba1 protein were 0.68±0.10,1.30±0.28 and 0.89±0.05,respectively.The above indexes in the model group were statistically significant compared with the experimental group and the normal group(all P＜0.01).Conclusion HYP plays a therapeutic role in PD by inhibiting the expression of NLRP3 inflammasome in PD mice.

Objective Viral encephalitis is an infectious disease severely affecting human health.It is caused by a wide variety of viral pathogens,including herpes viruses,flaviviruses,enteroviruses,and other viruses.The laboratory diagnosis of viral encephalitis is a worldwide challenge.Recently,high-throughput sequencing technology has provided new tools for diagnosing central nervous system infections.Thus,In this study,we established a multipathogen detection platform for viral encephalitis based on amplicon sequencing. Methods We designed nine pairs of specific polymerase chain reaction(PCR)primers for the 12 viruses by reviewing the relevant literature.The detection ability of the primers was verified by software simulation and the detection of known positive samples.Amplicon sequencing was used to validate the samples,and consistency was compared with Sanger sequencing. Results The results showed that the target sequences of various pathogens were obtained at a coverage depth level greater than 20×,and the sequence lengths were consistent with the sizes of the predicted amplicons.The sequences were verified using the National Center for Biotechnology Information BLAST,and all results were consistent with the results of Sanger sequencing. Conclusion Amplicon-based high-throughput sequencing technology is feasible as a supplementary method for the pathogenic detection of viral encephalitis.It is also a useful tool for the high-volume screening of clinical samples.

AIM To study the neoflavonoids from Dalbergia cochinchinensis Pierre ex Laness and their anti-hypoxia/reoxygenation injury activities on H9c2 myocardial cells.METHODS The 70%ethanol extract from D.cochinchinensis was isolated and purified by silica gel,Sephadex LH-20 and reverse-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The CCK-8 method was used to detect their activities on H9c2 cells and protective effects on hypoxia-reoxygenation injury of H9c2 cells,and their structure-activity relationship was analyzed.RESULTS Twelve compounds were isolated and identified as latifolin(1),5-O-methyllatifolin(2),mimosifoliol(3),5-O-methydalbergiphenol(4),dalbergiphenol(5),cearoin(6),2,4-dihydroxy-5-methoxy-benzophenone(7),2-hydroxy-4,5-dimethoxybenzophenone(8),melannoin(9),2,2′,5-trihydroxy-4-methoxybenzophenone(10),dalbergin(11),4-methoxydalbergione(12).The dalbergiphenols and dalbergins had little toxicity to H9c2 cells,and dalbergiphenols had strong activity against hypoxia-reoxygenation injury of H9c2 cells.CONCLUSION Compound 8 is a new natural product.Compounds 4,9 are isolated from this plant for the first time.Dalbergiphenols may be the main neoflavonoids against hypoxia-reoxygenation injury of H9c2 cells.

Objective To understand the growth and development status and differences between small for gestational age(SGA)and appropriate for gestational age(AGA)preterm infants during corrected ages 0-24 months,and to provide a basis for early health interventions for preterm infants.Methods A retrospective study was conducted,selecting 824 preterm infants who received regular health care at the Guangzhou Women and Children's Medical Center from July 2019 to July 2022,including 144 SGA and 680 AGA infants.The growth data of SGA and AGA groups at birth and corrected ages 0-24 months were analyzed and compared.Results The SGA group had significantly lower weight and length than the AGA group at corrected ages 0-18 months(P<0.05),while there were no significant differences between the two groups at corrected age 24 months(P>0.05).At corrected age 24 months,85%(34/40)of SGA and 79%(74/94)of AGA preterm infants achieved catch-up growth.Stratified analysis by gestational age showed that there were significant differences in weight and length at corrected ages 0-9 months between the SGA subgroup with gestational age<34 weeks and the AGA subgroups with gestational age<34 weeks and≥34 weeks(P<0.05).In addition,the weight and length of the SGA subgroup with gestational age≥34 weeks showed significant differences compared to the AGA subgroups with gestational age<34 weeks and≥34 weeks at corrected ages 0-18 months and corrected ages 0-12 months,respectively(P<0.05).Catch-up growth for SGA infants with gestational age<34 weeks and≥34 weeks mainly occurred at corrected ages 0-12 months and corrected ages 0-18 months,respectively.Conclusions SGA infants exhibit delayed early-life physical growth compared to AGA infants,but can achieve a higher proportion of catch-up growth by corrected age 24 months than AGA infants.Catch-up growth can be achieved earlier in SGA infants with a gestational age of<34 weeks compared to those with≥34 weeks.

Objective To investigate the clinical effect of unilateral percutaneous vertebroplasty(PVP)combined with 3D printing technology for the treatment of thoracolumbar osteoporotic compression fracture.Methods A total of 77 patients with thoracolumbar osteoporotic compression fractures from October 2020 to April 2022 were included in the study,all of which were vertebral body compression fractures caused by trauma.According to different treatment methods,they were di-vided into experimental group and control group.Thirty-two patients used 3D printing technology to improve unilateral transpedicle puncture vertebroplasty in the experimental group,there were 5 males and 27 females,aged from 63 to 91 years old with an average of(77.59±8.75)years old.Forty-five patients were treated with traditional bilateral pedicle puncture vertebroplasty,including 7 males and 38 females,aged from 60 to 88 years old with an average of(74.89±7.37)years old.Operation time,intraoperative C-arm X-ray times,anesthetic dosage,bone cement injection amount,bone cement diffusion good and good rate,complications,vertebral height,kyphotic angle(Cobb angle),visual analogue scale(VAS),Oswestry disability index(ODI)and other indicators were recorded before and after surgery,and statistically analyzed.Results All patients were followed up for 6 to 23 months,with preoperative imaging studies,confirmed for thoracolumbar osteoporosis com-pression fractures,two groups of patients with postoperative complications,no special two groups of patients'age,gender,body mass index(BMI),time were injured,the injured vertebral distribution had no statistical difference(P＞0.05),comparable data.Two groups of patients with bone cement injection,bone cement dispersion rate,preoperative and postoperative vertebral body height,protruding after spine angle(Cobb angle),VAS,ODI had no statistical difference(P＞0.05).The operative time,intra-operative fluoroscopy times and anesthetic dosage were statistically different between the two groups(P＜0.05).Compared with the traditional bilateral puncture group,the modified unilateral puncture group combined with 3D printing technology had shorter operation time,fewer intraoperative fluoroscopy times and less anesthetic dosage.The height of anterior vertebral edge,kyphosis angle(Cobb angle),VAS score and ODI of the affected vertebrae were statistically different between two groups at each time point after surgery(P＜0.05).Conclusion In the treatment of thoracolumbar osteoporotic compression fractures,3D printing technology is used to improve unilateral puncture PVP,which is convenient and simple,less trauma,short operation time,fewer fluoroscopy times,satisfactory distribution of bone cement,vertebral height recovery and kyphotic Angle correction,and good functional improvement.

In recent years, the development of host-acting antibacterial compounds has gradually become a hotspot in the field of anti-infection. Through research on the interaction mechanism between hosts and pathogenic bacteria, it has been found that the immune system is one of the key targets of host-acting antibacterial compounds. There is a communication system called the quorum sensing system in microorganisms, which mainly adjusts the structure of multi-microbial community and coordinates the group behavior. When the quorum sensing molecules secreted by microorganisms reach a threshold concentration, the quorum sensing system is activated and the overall gene expression of the microorganism is changed. In addition to regulating the density of microorganisms, quorum sensing molecules can also act as a link between pathogenic microorganisms and hosts, entering the host immune system and playing a role in affecting the morphological structure of immune cells, secreting cytokines, and inducing apoptosis, leading to host immune injury and causing host immune dysfunction.The key mechanism of 3-oxo-C12-HSL and other acyl-homoserine lactone (AHL) molecules in the innate immune system has been extensively studied. The lipid solubility allows AHLs to pass through the plasma membrane of host immune cells easily and induce dissolution of lipid domains. Then, it acts through signaling pathways such as p38MAPK and JAK-STAT, further influencing the immune cell’s defense response to bacteria and potentially leading to cell apoptosis. Additionally, the human lactonase paraoxonase 2, which can degrade3-oxo-C12-HSL, has been found in macrophage. It acts as an immune regulator that promotes macrophage phagocytosis of pathogens and is hypothesized to have the ability to reduce bacterial resistance. The mechanism of quorum sensing molecules in the adaptive immune system is less studied, the current results suggest that 3-oxo-C12-HSL is closely related to the mitochondrial pathway in host immune cells. For example, 3-oxo-C12-HSL induces apoptosis of Jurkat cells by inhibiting the expression of three mitochondrial electron transport chain proteins; it can also trigger mitochondrial dysfunction and induce mast cell apoptosis through Ca²⁺ signaling.Among the quorum sensing molecules, the AHLs have the greatest impact on plant immune system. The different effects on plant resistance depends on the chain lengths of acyl groups in bacterial-produced AHLs. Short-chain AHLs (C4-HSL and C8-HSL) induce plant resistance to pathogenic bacteria mainly through the auxin pathway and jasmonic acid pathway. Long-chain AHL (3-oxo-C14-HSL) is commonly used in hosts against fungal pathogens by inducing stomata defense responses, and the reaction process is related to salicylic acid. Diffusible signal factor molecules also interfere with the stomatal immunity caused by pathogens. It may act through the formin nanoclustering-mediated actin assembly and MPK3 pathway to inhibit the innate immunity of Arabidopsis. In summary, AHLs induced different plant pathways and affects the plant-bacteria interactions to trigger plant immunity. As a quorum sensing molecule of fungi, farnesol has similar effects on host immunity as AHLs, such as stimulating cytokine secretion and activating an inflammatory response. It also plays a unique role on dendritic cell differentiation and maturation. In addition, studies have found that farnesol has a protective effect on autoimmune encephalomyelitis, which may be related to its effect on the composition of intestinal microorganisms of the host.Therefore, targeting the host immune system and quorum sensing molecules to develop antibacterial compounds can effectively inhibit the invasion of pathogens and subserve the host to resist the influence of pathogenic bacteria. This article will review the mechanism of host immune responses triggered by important quorum sensing molecules, aiming to explore the targets of host-acting antibacterial compounds and provide new directions for the prevention or treatment of causative infectious sources and the development of related drugs.

Biomacromolecule drugs have been increasingly used in clinical practice due to their distinct advantages, including precise targeting, small dose, high safety and activity. However, owing to their high molecular weight, strong hydrophilicity, and poor stability in the gastrointestinal tract, the oral bioavailability of the biomacromolecule drugs remains extremely poor. As a novel and innovative technology for active drug delivery, gastrointestinal microneedles hold immense potential in the oral delivery of biomacromolecule drugs because of their low-invasive nature and high permeation enhancement effects. This review primarily summarizes the actuating force, design strategies, fabrication techniques, and applications of gastrointestinal microneedles for the oral delivery of biomacromolecule drugs. Additionally, the challenges and further perspectives in the development this technology are presented, aiming to promote the subsequent research and clinical translation of gastrointestinal microneedles, and to provide a new efficient and safe strategy for oral delivery of biomacromolecule drugs.