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 effect of quercetin on the aging model of bone marrow mesenchymal stem cells established under microgravity. Methods Using 3D gyroscope, a aging model of bone marrow mesenchymal stem cells was constructed, and after receiving quercetin and microgravity treatment, the anti-aging effect of the quercetin was evaluated by detecting related proteins and oxidation indexes. Results Compared to the control group, the expressions of age-related proteins p21, pi6, p53 and RB in the microgravity group significantly increased, while the expressions of cyclin D1 and lamin B1 significantly decreased, with statistical significance (P<0.05). In the microgravity group, mitochondrial membrane potential significantly decreased (P<0.05), ROS accumulation significantly increased (P <0.05), SOD content significantly decreased and MDA content significantly increased (P<0.05). Compared to the microgravity group, the expressions of age-related proteins p21, pi6, p53 and RB in the quercetin group significantly decreased, while the expressions of cyclin D1 and lamin B1 significantly increased, with statistical significance (P<0.05). In the quercetin group, mitochondrial membrane potential significantly increased (P<0.05), ROS accumulation significantly decreased (P<0.05), SOD content significantly increased and MDA content significantly decreased (P<0.05). Conclusions Quercetin can resist oxidation, protect mitochondrial function and normal cell cycle, thus delaying the aging of bone marrow mesenchymal stem cells induced by microgravity.

Aim To prepare tripterygium glycoside nanoparticles and probe into their therapeutic effect on collagen-induced arthritis ( CIA) rats. Methods Tripterygium glycosides polyglycoside nanoparticles were prepared by thin film dispersion method and their quality was assessed. The CIA model was established and drug intervention performed. The body weight, toe swelling degree and arthritis index were measured. The pathological changes of the organs, knee and ankle synovium were observed. The serum levels of kidney function and inflammatory cytokine expression were detected in rats. Results The prepared tripterygium wil-fordii polyglycoside nanoparticles were round particles with uniform distribution and stable properties under electron microscope. Compared with the model group, the swelling of the left and right toes of medication group significantly decreased (P < 0. 01), and the ar-thritis index markedly decreased ( P < 0. 01). Among them, the efficacy of the TG-NPs group was better than that of the TG group. Compared with the normal group, the indexes of heart, spleen, kidney and testis all significantly decreased (P <0. 05, P<0.01). TG-NPs group had a significantly reduced pathological ankle-joint injury in knee cartilage and increased apoptotic synovial cells. Compared with the model group, the serum levels of ALT and BUN and CRE in TG-NPs group were significantly lower (P < 0. 05 ), and IL-1β, TNF-α and IL-6 levels decreased significantly (P <0. 05). Conclusions TG-NPs have good therapeutic effect on CIA through induction of synovial cell apoptosis and decrease of the expression of inflammatory cytokines. By intravenous injection of blood circula-tion, slow and controlled release of drugs can be achieved, the first pass effect caused by oral drug can be avoided, the viscera toxicity can be reduced, which provides an experimental basis for the development of new nanoagents for the treatment of rheumatoid arthritis.

Based on the interaction between supramolecule of traditional Chinese medicine and enterobacteria, the material basis of Rhei Radix et Rhizoma and Coptidis Rhizoma was explored. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) were used to characterize the morphological differences of Rhubarb single decoction, Coptis single decoction and Rhubarb and Coptis co-decoction. An in vitro antibacterial model (E. coli, E. faecium and B. subtilis) was established to evaluate the damage effect of the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma on enterobacteria. Ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to analyze the changes of chemical components of single decoctions and co-decoctions. The co-decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma was turbid after decocting. The spherical particles of 300-400 nm were observed under SEM, and the co-decoction was more uniform and stable than that of single decoction. The interaction between supramolecules formed after the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma and enterobacteria was significantly different from that of single decoction. In the process of interaction between supramolecules and enterobacteria, the spherical state was maintained, and the medicinal ingredients in Coptidis Rhizoma or Rhei Radix et Rhizoma were blocked, which could effectively alleviate the damage to enterobacteria. This study provided a reference for subsequent studies on the regulation of intestinal flora homeostasis by the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma.

Objective To study the pharmacokinetic characteristics of buspirone hydrochloride tablets in healthy adult populations under conditions of fasting and postprandial administration.Methods A single-center,randomized,three-cycle partially repeated crossover trial design was adopted,and 36 subjects were enrolled on fasting/postprandial,one tablet of the test preparation was taken in one cycle,one tablet of reference preparation(5 mg of buspirone tablets)was taken once in each of 2 cycles,the drug concentration of buspirone in plasma was determined by liquid chromatography-tandem mass spectrometry,and the pharmacokinetic parameters were calculated by WinNonlin software.Results Main pharmacokinetics of buspirone after oral administration of test and reference preparations in fasting group,the Cmax was(285.72±286.08)and(308.94±341.03)pg·mL-1;AUC0-t were(577.09±491.10)and(618.62±642.56)pg·mL-1·h;AUC0-∞ were(586.85±510.04)and(655.92±687.95)pg·mL-1·h;tmax was 0.75(0.33-4.00)and 0.75(0.33-1.75)h.Main pharmacokinetics of buspirone after oral administration of test and reference preparations in the postprandial group,the Cmax were(676.36±603.64)and(760.33±610.27)pg·mL-1;AUC0-t were(1 755.58±1 001.69)and(1 743.00±1 073.33)pg·h·mL-1;AUC0-∞ were(1 839.97±1 044.60)and(1 818.00±1 106.95)pg·mL-1·h;tmax was 1.25(0.25-4.50)and 1.00(0.25-3.50)h.The 90％confidence intervals of the AUC0-t and AUC0-∞ geometric mean ratios of the test preparation and the reference preparation in the fasting test and the postprandial test all fell between 80.00％and 125.00％,and the 95％upper confidence limit of of Cmax was ≤0 and geometric mean ratios point estimates fall between 80.00％and 125.00％.Conclusion Two kinds of buspirone hydrochloride are bioequivalent in Chinese healthy adult subject.

Radiation mainly comes from medical radiation,industrial radiation,nuclear waste and atmospheric ultraviolet radiation,etc.,radiation is divided into ionizing radiation and non-ionizing radiation.Studying the effects of ionizing and non-ionizing radiation on drug metabolism,understanding the absorption and distribution of drugs in the body after radiation and the speed of elimination under radiation conditions can provide reasonable guidance for clinical medication.This article reviews the effects of radiation on the pharmacokinetics of different drugs,elaborates the changes of different pharmacokinetics under radiation state,and discusses the reasons for the changes.

AIM To study the amino acids and proteins in 16 batches of commercial fish swim-bladders with different origins.METHODS A high performance liquid chromatography method based on pre-column derivatization using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate(AQC)was developed for the determination of contents and components of 17 amino acids in fish swim-bladders.Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)was performed to analyze the molecular weight distribution of proteins from different fish swim-bladders,and proteins in fish swim-bladders were identified by proteomics method.RESULTS The result showed that the determination of 17 amino acids had a good linear relationship(R2≥0.998 0).The average recovery rate was 85.62%-109.60%and the relative standard deviations of precision,stability and repeatability were less than 3.5%.The total content of the 17 amino acids in 16 batches of fish swim-bladders ranged from 468.31 mg/g to 620.05 mg/g.A total of 688 proteins including 11 collagens were identified from 16 batches of fish swim-bladder samples and a plenty of low-abundance proteins at 52-95 kDa were also detected in fish swim-bladders by SDS-PAGE.CONCLUSION This study provides a good reference for the quality evaluation and further utilization of fish swim-bladders.

Objective This study aimed to investigate the potential relationship between urinary metals copper (Cu), arsenic (As), strontium (Sr), barium (Ba), iron (Fe), lead (Pb) and manganese (Mn) and grip strength. Methods We used linear regression models, quantile g-computation and Bayesian kernel machine regression (BKMR) to assess the relationship between metals and grip strength.Results In the multimetal linear regression, Cu (β=-2.119), As (β=-1.318), Sr (β=-2.480), Ba (β=0.781), Fe (β= 1.130) and Mn (β=-0.404) were significantly correlated with grip strength (P < 0.05). The results of the quantile g-computation showed that the risk of occurrence of grip strength reduction was -1.007 (95％ confidence interval:-1.362, -0.652; P < 0.001) when each quartile of the mixture of the seven metals was increased. Bayesian kernel function regression model analysis showed that mixtures of the seven metals had a negative overall effect on grip strength, with Cu, As and Sr being negatively associated with grip strength levels. In the total population, potential interactions were observed between As and Mn and between Cu and Mn (Pinteractions of 0.003 and 0.018, respectively).Conclusion In summary, this study suggests that combined exposure to metal mixtures is negatively associated with grip strength. Cu, Sr and As were negatively correlated with grip strength levels, and there were potential interactions between As and Mn and between Cu and Mn.

Objective To investigate the effects of Tuina targeting different body parts on the behaviors and gut microflora of rat models with valproic acid(VPA)-induced autistic spectrum disorder(ASD). Methods Twenty female Sprague Dawley(SD)rats with 12.5 d of pregnancy were randomly divided into VPA model group[intraperitoneal injection of VPA(600 mg/kg),n=15]and saline group(intraperitoneal injection of equal amount of normal saline,n=5).The offspring male rats injected with saline were secleted as control group.The offspring male rats injected with VPA were randomly divided into VPA,dorsal,and abdominal groups(n=7 in each group).On the 21st day after birth,three-chamber social test,open field test,and marble-burying test were carried out to observe the social abilities,anxiety behaviors,and stereotypi-cal behaviors of rats in the four groups.Rats in dorsal and abdominal groups underwent Tuina for 14 d,twice a day.On the 35th day,behavioral tests were conducted again,and in-testinal contents were taken for species composition and structural analysis,as well as mark-er and differential species analysis. Results(i)According to behavioral observations,compared with VPA group,the social and movement time in the central open field of rats in dorsal group increased significantly(P<0.05),and the number of buried marbles decreased markedly(P<0.01),indicating improve-ment on their social abilities,anxiety behaviors,and stereotypical behaviors as consequences of dorsal Tuina;and the number of buried marbles was reduced as well in abdominal group when compared with VPA group(P<0.05),suggesting the improvement on their stereotypi-cal behaviors following abdominal Tuina.In the marble-burying test,the number of marbles buried in dorsal group was less than in abdominal group,and the stereotypical behaviors were improved more significantly(P<0.05),and there were no significant differences in the three-chamber social and open field tests between the two groups(P>0.05).(ii)In accor-dance with intestinal microflora detection results,compared with VPA group,both dorsal and abdominal groups showed increased richness(P<0.05)and elevated diversity(P<0.05 in dorsal group and P<0.01 in abdominal group)in intestinal microflora.The results of differen-tial analysis indicated that at the phylum level,compared with VPA group,the relative abun-dance of Firmicutes in rats in abdominal group showed a significant reduction trend(P<0.05);at the genus level,compared with VPA group,the relative abundance of Lactobacillus in rats in dorsal and abdominal groups decreased significantly(P<0.05).Dorsal group also showed significant increase in the genus Blautia in the analysis of marker species compared with VPA group(P<0.05). Conclusion Tuina impacted the behavior and gut microflora structure of ASD model rats.Dorsal intervention had a significant effect on social abilities,anxiety behaviors,and stereo-typical behaviors of ASD model rats,while abdominal intervention only had an obvious effect on stereotypical behaviors.Both dorsal and abdominal interventions increased the richness and diversity of gut microflora of ASD model rats,with abdominal intervention improving the intestinal microbial diversity more significantly and resulting in a more uniform species dis-tribution.

Objective:To investigate the efficacy and side effects of concurrent chemoradiotherapy with or without nimotuzumab in the treatment of locally advanced nasopharyngeal carcinoma after neoadjuvant chemotherapy.Methods:In the prospective study, 100 patients with stage Ⅲ-Ⅳa locally advanced nasopharyngeal carcinoma (except T 3N 0M 0 stage) who met the inclusion criteria were randomly divided into the experimental and control groups using the random number table method. Patients in both groups were treated with neoadjuvant chemotherapy using TPF (paclitaxel liposome, cisplatin, and 5-fluorouracil) regimen for 2 cycles. At 2 weeks after chemotherapy, concurrent chemoradiotherapy plus nimotuzumab targeted therapy was given in the experimental group, and concurrent chemoradiotherapy was delivered in the control group. The main observation index was the distant metastasis-free survival (DMFS) rate. Log-rank test and multivariate Cox regression analysis were used. Results:The objective remission rate and complete remission rate in the experimental and control groups were 100% vs. 98% ( P=1.000) and 92.0% vs. 80% ( P=0.084). The 3-year DMFS in the experimental and control groups were 91.4 % vs. 76.1 % ( P=0.043). The 3-year progression-free survival (PFS), locoregional recurrence-free survival (LRFS) and overall survival (OS) in two groups were 87.3 % vs. 74.1 % ( P=0.097), 94.5 % vs. 85.6 % ( P=0.227) and 90.5% vs. 85.2% ( P=0.444). Subgroup analysis showed that patients with age<60 years ( HR=0.34, 95% CI=0.12-0.94, P=0.037), neutrophil-to-lymphocyte ratio (NLR)≤4 ( HR=0.34, 95% CI=0.13-0.89, P=0.028) received concurrent chemoradiotherapy plus nimotuzumab obtained better PFS. Multivariate analysis showed that NLR was an independent risk factor for disease progression ( HR=5.94, 95% CI=1.18-29.81, P=0.030) and distant metastasis ( HR=13.76, 95% CI=1.52-124.36, P=0.020). Conclusions:Compared with concurrent chemoradiotherapy alone, concurrent chemoradiotherapy combined with nimotuzumab after neoadjuvant chemotherapy can significantly increase DMFS rate for patients with locally advanced nasopharyngeal carcinoma. The incidence of side effects is similar in two groups. Concurrent chemoradiotherapy plus nimotuzumab after neoadjuvant chemotherapy may be a preferred treatment strategy for locally advanced nasopharyngeal carcinoma.