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.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Immunoinflammation mediates the development of hypertensive nephropathy,and aberrant activation of the complement system,an important component of the innate immune system,plays an important role in the development of hypertensive nephropathy.Complement inhibition is expected to be a potential strategy for the treatment of hypertensive nephropathy.In this article,we summarized and reviewed relevant studies on the complement system in the development of hypertensive nephropathy,and complement-targeted drug therapy,aiming to provide new ideas for clinicians on the clinical diagnosis and treatment of hypertensive nephropathy.

Objective:To investigate the clinical manifestation, therapy, and prognosis of Susac syndrome and enhance the understanding of this disease.Methods:A case summary was made.The clinical data of two siblings with Susac syndrome treated at Children′s Medical Center, Peking University First Hospital in January 2024 were summarized.Reported cases of pediatric Susac syndrome were reviewed.Results:The onset of the disease in the two siblings was at the age of 3.00 and 6.75 years, with recurrent headaches, tinnitus, hearing loss and encephalopathy symptoms.Cranial magnetic resonance imaging showed multiple cerebral microbleeding and microinfarction lesions, " snowball like" in the corpus callosum and diffuse white matter edema in the brain.Audiometry revealed sensorineural hearing loss.In one case, ophthalmic fluorescein angiography revealed ischemic changes due to branch retinal artery occlusions.No pathogenic variants were detected in gene testing.This child was diagnosed with Susac syndrome, and the symptoms were improved after treatment with Corticosteroids and Rituximab.No relapse was observed during the 9-month follow-up.A total of 20 pediatric cases of Susac syndrome were retrieved, including 18 reported previously and 2 cases from this study.There were 2 boys and 18 girls, with the age of onset ranging from 2.5 to 17.0 years.The common initial symptoms included headache (19 cases), vertigo and tinnitus or hearing loss (9 cases), and vision impairment or visual field defect (4 cases). The symptoms were improved after immunotherapy.Conclusions:With a low incidence, Susac syndrome is rare in children and difficult to diagnose.There may be a genetic predisposition in such disease.Early diagnosis and immunotherapy can low the relapse and improve the prognosis.

Hypercholesterolemia is pathologically characterized by abnormal accumulation of low-density lipoprotein cholesterol,which is closely associated with metabolic dysfunction-associated fatty liver disease and increased cardiovascular risks.Hepatocytes maintain cholesterol homeostasis through LDL receptor-mediated uptake and esterification storage mechanisms.However,chronic cholesterol overload induces mitochondrial dysfunction,reactive oxygen species accumulation,and endoplasmic reticulum stress,leading to hepatocyte injury.Moreover,systemic hypercholesterolemia disrupts gut microbiota balance and impairs short-chain fatty acid and ketone metabolism,exacerbating metabolic disturbances and aggravating hepatic injury through enhanced metabolic stress.In this article,we review the advance of studies on hypercholesterolemia in recent years and summary its association with hepatic injury,which can provide theoretical support for further research.

The aim of this study is to identify the linear Fc-binding epitope for IgG1 on bovine IgG Fc receptor Ⅱ(boFcγRⅡ)to understand the molecular basis of IgG-Fcγ interaction.The boFcγRⅡ molecules were expressed on cell surface of the boFcγR Ⅱ-transfected COS-7 cells.The extracel-lular domain of boFcγRⅡ was expressed in NS0 cells,and the boFcγRⅡ recombinant protein was purified from ascites by Ni-chelation chromatography.Peptides derived from the membrane-distal extracellular domain(EC2)of boFcγR Ⅱ were synthesized and conjugated to a carrier protein of IgG-free bovine serum albumin(BSA).Binding of bovine IgG1 to the different peptides was tested by dot-blot assay,and the IgG-binding peptide was further modified by truncation and mutation to identify the Fc-binding epitope as well as its key amino acids for Fc-binding.The inhibition effect of the Fc-binding peptide was determined by competitive ELISA and Fc-rosetting inhibition assay,re-spectively.The results showed that boFcγR Ⅱ molecules were stably expressed on surface of the transfected COS-7 cells,which showed about 90％rosetting with IgG1-RBCs.The soluble boFcγRⅡ recombinant protein specifically bound to bovine IgG1.The minimal effective peptide of 122FYQDRKSKIF131 of boFcγRⅡ was able to bind bovine IgG1 specifically,suggesting it repre-sents a linear Fc-binding epitope located in the putative C-C'loop of the EC2 domain on the recep-tor.The Ala-substitution of Phe122,Tyr123,Arg126,Lys127,Ser128,Lys129 or Phe131 within the linear epitope led to a complete loss of its IgG1-binding capability,indicating those residues are critical for IgG1-binding on boFcγRⅡ.The Fc-binding peptide inhibited bovine IgG1 binding to the soluble recombinant protein of boFcγRⅡ with IC50 of 20.05 μmol/L,and inhibited the rosette formation of bovine IgG1-sensitized RBCs on the boFcγRⅡ transfected cells with IC50 of 80.15 μmol/L.The re-sults indicate that boFcγRⅡ possesses the linear epitope for Fc-binding,and the Fc-binding pep-tide showed well capability of regulating boFcγR Ⅱ-IgG1 interaction on cell surface,thereby provi-ding a research foundation for understanding the IgG-Fcγ interaction.

Aim To investigate the intervention effect of Rehmannia radix water extract on bleomycin(BLM)-induced pulmonary fibrosis in mice combined with metabolomics and to reveal the potential mechanism,in order to provide new ideas for clinical treatment of pul-monary fibrosis.Methods Male C57BL/6N mice were randomly divided into the control group,model group,pirfenidone group(positive control,PFD,270 mg·kg-1),and low dose(DH-L,4.55 g·kg-1)group,medium dose(DH-M,9.1 g·kg-1)group and high dose(DH-H,18.2 g·kg-1)group of Rehman-nia.Except for the control group,BLM(5 mg·kg-1)was instilled into the trachea to establish the model of pulmonary fibrosis in the other groups.The survival rate,lung index and blood oxygen saturation of mice in each group were evaluated.HE and Masson staining were used to observe the pathological changes of lung tissue.WBP was used to detect lung function.Flow cytometry was used to detect the apoptosis of primary lung cells,ROS and immune cells.ELISA was used to detect the levels of fibrosis markers and inflammatory factors(α-SMA,collagen Ⅰ,collagen Ⅲ,TGF-β1,TNF-α,IL-1 β,and IL-6).Biochemical method was employed to detect the contents of GSH-Px,T-SOD and MDA.Liquid chromatograph mass spectrometer(LC-MS)metabolomics was used to analyze the changes of serum metabolic profile.Results Water extract of Re-hmannia significantly increased the survival rate,oxy-gen saturation and lung function of mice with pulmona-ry fibrosis,reduced the lung coefficient,ameliorated pathological damage and collagen deposition in lung tissue,reduced the levels of apoptosis and oxidative stress,and down-regulated the levels of inflammatory factors in lung tissue.It regulated the levels of metabo-lites such as bile acid metabolism,sphingolipid metabo-lism,and unsaturated fatty acid metabolism.Conclu-sions Water extract of Rehmannia inhibits lung injury and collagen deposition in mice with pulmonary fibrosis by inhibiting inflammatory response,which may be a-chieved by regulating the levels of inflammatory factors through the metabolic pathways of bile acid and sphin-golipid.

Objective:To investigate the clinical efficacy of Zhuangdan Yanshi Decoction combined with dapoxetine hydrochlo-ride in the treatment of premature ejaculation with cholestasis and phlegm disturbance.Methods:A total of 120 patients diagnosed with premature ejaculation and treated in the Andrology Outpatient Department of Shaanxi Provincial Hospital of Traditional Chinese Medicine from March to December in 2022 were selected and randomly divided into treatment group and control group,with 60 cases in each group.The incubation period of intravaginal ejaculation(IELT),the Diagnostic Scale of Premature Ejaculation(PEDT),the Premature Ejaculation Assessment Scale(PEP),the 5-item Sexual Function Evaluation of Chinese Premature Ejaculation Patients(CIPE-5)and the improvement of traditional Chinese medicine symptom scores were compared before and after the treatment.And the adverse reactions were recorded as well.Results:A total of 105 cases were ultimately included,with 55 cases in the treatment group and 50 cases in the control group.Measurable improvements in IELT,PEDT scores,PEP scores,CIPE scores and TCM symptom scores had been found after treatment in both of two groups(P＜0.05).Moreover,the improvement in the treatment group was superi-or to that in the control group(P＜0.05).The total effective rate in the treatment group was 89.1％,which was higher than that(84％)in the control group,with no statistically significant difference between the two groups(P＞0.05).The incidence of adverse reactions in the treatment group was 9.1％,which was 24％in the control group.There was significantly difference between two groups(P＜0.05).Conclusion:The combination therapy with Zhuangdan Yanshi Decoction and dapoxetine hydrochloride for premature ejaculation associated with cholestasis and phlegm disturbance syndrome is definite,and it can reduce the side effects of drugs,which is better than oral dapoxetine hydrochloride alone.

Objective To compare image quality and clinical usefulness between single breath-hold three-dimensional magnetic resonance cholangiopancreatography with compressed sensing(3D BH-CS-MRCP)and with gradient and spin-echo(3D BH-GRASE-MRCP)and conventional three-dimensional breath-triggered magnetic resonance cholangiopancreatography(3D RT-MRCP).Methods A retrospective analysis was performed in 48 patients(26 males and 22 females,mean age of 53.14±15.19 years),who underwent 3D BH-GRASE-MRCP,3D BH-CS-MRCP and 3D RT-MRCP from September to December 2023.Pancreaticobiliary duct visibility,motion artifacts,background suppression,and overall image quality were scored on a 5-point scale by two radiologists.The relative contrast ratio of three bile duct segmentations(common bile duct,left and right intrahepatic bile ducts)were calculated,and the acquisition time of the three sequences was recorded.Friedman test with a post-hoc test was performed to compare image acquisition time,qualitative and quantitative results.Results The acquisition time was significantly shorter in the two breath-hold groups than for conventional 3D RT-MRCP(P＜0.001).There were no significant differences in overall image quality,motion artifacts,common bile duct and primary branch of intrahepatic bile duct among the three groups.The relative contrast ratio,intrahepatic biliary secondary branch visibility and background suppression score of 3D RT-MRCP and BH-CS-MRCP were significantly higher than those of BH-GRASE-MRCP(P＜0.01).The pancreatic duct(proximal,middle,distal)visibility score of 3D RT-MRCP was significantly better than that of BH-GRASE-MRCP(P=0.002,0.043,0.001),but the gallbladder and gallbladder duct visibility score of BH-GRASE-MRCP was higher than that of 3D RT-MRCP(P=0.036).There was no significant difference between 3D RT-MRCP and BH-CS-MRCP scores except for the middle and distal pancreatic duct visibility.Conclusion Breath-hold 3D MRCP with GRASE and CS can give us feasible options for pancreaticobiliary diagnosis,which significantly shortens the acquisition time without reducing the overall image quality.Compared with BH-GRASE-MRCP,BH-CS-MRCP has better consistency in pancreaticobiliary duct visibility and background suppression.

Plutonium isotopes(238Pu,239Pu,240Pu and 241Pu)in the environment are important"fingerprint"nuclides in the study of nuclear activity traceability.The content of plutonium isotopes in the environmental metrics is usually very low,and the measurement of these isotopes,especially 238Pu,using mass spectrometry is seriously interfered with by the coexisting 238U.The analysis of several plutonium isotopes in soil usually requires combination of multiple measurement techniques,which leads to a long analysis time and large uncertainty in the isotope ratio.In this work,the hydrous titanium oxide(HTiO)precipitated by the hydrolysis of titanium oxydichloride(TiOCl2)under near-neutral condition was used to preconcentrate plutonium from the soil digestion solution,and the highly efficient decontamination of 238U in the sample was achieved by TK200 resin column chromatography with a decontamination factor of 108.Simulation resuts of density functional theory(DFT)showed that NH3 was considered as a promising reaction gas to eliminate the interference of 238U from 238Pu measurement using mass spectrometry due to the significant discrepancy of the chemical reactivity of U+and Pu+with the reactive gas NH3.Experiments confirmed that by optimizing the flow rates of collision gas(He)and reaction gas(NH3),the interference of 238U could be effectively suppressed,and the decontamination factor of 238U was 104.Combined with chemical separation,the overall decontamination factor of 238U could reach 1012 by using the developed method.By combining chemical separation and tandem quadrupole inductively coupled plasmon-mass spectrometry(ICP-MS/MS)measurement,the simultaneous determination of four ultra-trace plutonium isotopes in soil was realized,and the detection limit of plutonium isotopes was at the femtogram level.Analysis of the international standard reference materials(NIST-SRM-4357 and IAEA-384)showed that the established method could be successfully used for the accurate analysis of ultra-trace four plutonium isotopes(238Pu,239Pu,240Pu and 241Pu)in soil samples.