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 Kurtosis reflecting noise's temporal structure is an effective metric for evaluating noise-induced hearing loss (NIHL), and its threshold is still unclear. Objective To explore the energy range of kurtosis and the threshold of NIHL induced by kurtosis in this energy rangeMethods Using cross-sectional design, 4631 noise-exposed workers in manufacturing industry were selected. The hearing loss and noise exposure data of each worker were collected. Logistic regression model was used to establish the dose-response relationship between noise exposure and hearing loss and estimate the range of energy effects. Restricted cubic spline model was utilized to analyze the dose-response relationship curves of kurtosis to noise-induced hearing loss (NIHI) and high-frequency noise-induced hearing loss (HFNIHL) under different 8 h equivalent sound levels (L_{EX,8 h}), as well as to estimate the kurtosis effect threshold. Results The logistic regression model analysis showed that the prevalence of NIHI and HFNIHL increased significantly with increase of L_{EX,8 h} for steady noise; when L_{EX,8 h} of non-steady noise was 80-100 dB(A), the risk of hearing loss increased with an increase in kurtosis (P<0.05). The restricted cubic spline model showed that when L_{EX,8 h} of non-steady noise was 0-80 dB(A) or >100 dB(A), there was no significant relationship between kurtosis and NIHI or HFNIHL. When L_{EX,8 h} was 80-100 dB(A), there was a significant nonlinear dose-response relationship between kurtosis and NIHL or HFNIHL (P <0.001), and kurtosis > 28.08 exerted effect in elevating NIHI or HFNIHL. Conclusion The effect threshold of kurtosis on NIHL is 28.08 when non-steady noise levels are in the range of 80-100 dB(A). The effect threshold of kurtosis needs further verification.

Background Temporal kurtosis (without frequency weighting, i.e., Z-weighted kurtosis) can evaluate noise-induced hearing loss (NIHL). However, few studies have considered the function of frequency weighting (A- or C-weighted) kurtosis on NIHL. Objective To study the significance of A- and C-weighted kurtosis adjustment for equivalent sound level (L'_{EX,8 h}) in evaluating occupational hearing loss. Methods A cross-sectional survey was used to select 973 noise-exposed workers in seven industries as the subjects. The noise exposure of all workers was assessed by distributions of A-, C-, and Z-weighted kurtosis (e.g., K_A, K_C, and K_Z) and respective adjusted equivalent sound level (e.g., L'_{EX,8 h}-K_A, L'_{EX,8 h}-K_C, and L'_{EX,8 h}-K_Z). The significance of A- and C-weighted kurtosis in evaluating NIHL was evaluated by correlations between three types of L'_{EX,8 h} and NIHL, and improvement of noise-induced permanent threshold shift (NIPTS) underestimation predicted by the ISO prediction model (Acoustics—Estimation of noise-induced hearing loss, ISO 1999-2013). Results The median K_A, K_C, and K_Z were 68.33, 28.22, and 19.82, respectively. The binary logistic regression showed that L_{EX, 8 h}-K_A, L_{EX, 8 h}-K_C, and L'_{EX, 8 h}-K_Z were risk factors for NIHL (OR>1, P<0.001). The receiver operating characteristic (ROC) curve showed that when the outcome variable was noise-induced hearing impairment (NIHI), the areas under the curves corresponding to L'_{EX,8 h}-K_A, L'_{EX,8 h}-K_C, and L'_{EX,8 h}-K_Z were 0.625, 0.628, and 0.625, respectively. When the outcome variable was high-frequency noise-induced hearing loss (HFNIHL), the areas under the curves corresponding to L'_{EX,8 h}-K_A, L'_{EX, 8 h}-K_C, and L'_{EX,8 h}-K_Z were 0.624, 0.623, and 0.622, respectively (P<0.05). The order of underestimation improvement values predicted by L'_{EX,8 h} for NIPTS₁₂₃₄ was: L'_{EX,8 h}-K_A (4.68 dB HL)>L'_{EX,8 h}-K_C (4.38 dB HL)>L'_{EX,8 h}-K_Z (4.28 dB HL) (P<0.001). The order of underestimation improvement values predicted by L'_{EX,8 h}-K for NIPTS₃₄₆ was: L'_{EX,8 h}-K_A (7.20 dB HL)>L'_{EX,8 h}-K_C (6.83 dB HL)>L'_{EX,8 h}-K_Z (6.71 dB HL) (P<0.001). Conclusion The adjustment of A- and C-weighted kurtosis to equivalent sound level L_{EX,8 h} can effectively improve the accuracy of the ISO 1999 prediction model in NIPTS prediction, and compared with the C-weighted, the A-weighted kurtosis can improve the result of the ISO 1999 prediction model in terms of underestimating NIPTS.

T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

Aim To investigate the impact of Cinobu-facini on the proliferation,invasion,and apoptosis of HepG2 cells and the underlying mechanism.Methods The proliferation of HepG2 cells was assessed using the CCK-8 method following treatment with Cinobufaci-ni.The invasion capability of HepG2 cells was evalua-ted through Transwell assay after exposure to Cinobufa-cini.The apoptosis rates of HepG2 cells post Cinobufa-cini intervention were measured using flow cytometry,and the expression levels of VEGF in the culture medi-um of HepG2 cells were determined using enzyme-linked immunoassay.Furthermore,qRT-PCR and Western blot analyses were conducted to assess the im-pact of Cinobufacini on mRNA and protein expression levels related to the CXCL5/FOXD1/VEGF pathway.The interaction between CXCL5 and FOXD1 was inves-tigated via co-immunoprecipitation.Results Cinobufa-cini treatment led to a gradual decrease in HepG2 cell viability in a dose-dependent manner compared to the control group(P＜0.05).Moreover,Cinobufacini sig-nificantly suppressed HepG2 cell invasion(P＜0.05)while enhancing cell apoptosis(P＜0.05).Notably,Cinobufacini exhibited inhibitory effects on the CX-CL5/FOXD1/VEGF pathway,as evidenced by re-duced expression of related mRNA and proteins(P＜0.05).FOXD1 was identified as the binding site of CXCL5.Overexpression of CXCL5 resulted in in-creased proliferation and VEGF secretion by HepG2 cells(P＜0.05),and increased expression of FOXD1 and VEGF(P＜0.05).However,Cinobufacini inter-vention effectively inhibited liver cancer cell prolifera-tion and invasion(P＜0.05),promoted apoptosis(P＜0.05),reduced VEGF secretion by HepG2 cells(P＜0.05),and downregulated the expression of CXCL5 and FOXD1 in HepG2 cells(P＜0.05);but com-pared with the unexpressed group of Cinobufacini,its ability to inhibit cell activity was weakened(P＜0.05),and its ability to inhibit the expression of CX-CL5,FOXD1,and VEGF was weakened(P＜0.05).Conclusion Cinobufacini may inhibit HepG2 cell pro-liferation and invasion and promote HepG2 cell apopto-sis by regulating the CXCL5/FOXD1/VEGF pathway.

Objective To explore feasibility of 3D metal printing technology combined with virtual design proximal clavicle anatomical plate.Methods A 52-year-old male healthy volunteer was retrospectively selected to design proximal clavicle anatomical plate system by using Mimics15.01,NX12.0 and other software.STL data were input into 3D printer to print 1∶1 clavicle model and proximal clavicle anatomical plate.The fit of the plate was tested in vitro and the accuracy of screw position was evaluated by imaging.Printing time of model,nail path design and fabrication time of the anatomical plate at proximal clavicle were recorded.Results The 3D metal printing proximal clavicle anatomical plate fitted well to clavicle model,orienta-tion of proximal clavicle locking screw was accurate,and X-ray and CT scan showed the screw position was good.Printing time of model,the time of nail path design,and the time of making anatomical plate of proximal clavicle were 120,15 and 300 min respectively.Conclusion The proximal clavicular anatomical plate system based on 3D metal printing technology could achieve good lamination of proximal clavicular fracture plate and precise screw placement,providing a new and accurate surgical method for the treatment of the proximal clavicular fracture.

Objective To explore establishment and finite element analysis of personalized proximal clavicular anatomical plate screw fixation model.Methods A 40-year-old male healthy volunteer was selected and the finite element analysis modules of 3D reconstruction software Mimics 15.01,Hypermesh 2019 and Abaqus 2020 were used.The finite element model of anatomic plate at the proximal clavicle was established,and a vertical load of 250 N was applied to the distal end of long axis of clavicle about 15 mm,then the overall structure,plate and screw displacement cloud image,Mises stress distribution were ob-served.Results The displacement distribution of the overall structure shows the maximum displacement was distributed on the distal clavicle.Under the four conditions of normal upper limb weight,longitudinal clavicle fracture,oblique fracture and shoulder impact violence during fall,longitudinal clavicle fracture and oblique fracture,the maximum displacement were 1.04 mm,1.03 mm,1.35 mm and 1.33 mm,respectively.The displacement cloud map of titanium alloy steel plate showed the largest displacement was distributed near the distal clavicular bone,and the maximum displacement were 0.89 mm,0.88 mm,1.10 mm and 1.09 mm,respectively.The displacement cloud map of titanium alloy screw showed the largest displacement was distribut-ed at the root of the distal screw,and the maximum displacement were 0.88 mm,0.87 mm,1.08 mm and 1.06 mm,respectively.Mises stress distribution showed the maximum stress was mainly distributed on titanium alloy plates and screws,and the stress on the clavicle was very small.Mises stress distribution cloud showed the maximum Mises stress was distributed at the second row of screw holes near the clavicle,and the maximum Mises stress were 673.1,678.1,648.5,654.4 MPa,respectively.The maximum stresses of titanium alloy screws were 414.5,417.4,415.8 and 419.7 MPa,respectively.Conclusion The biomechan-ical changes of personalized proximal clavicular anatomical plates are demonstrated by using 3D finite element method to pro-vide biomechanical data for personalized proximal clavicular anatomical plates.

Objective To evaluate the clinical effect of a new three-phase Chinese medicine(CM)external treatment for acute lateral ankle ligament injuries.Methods From July to December 2023,64 patients with acute lateral ankle ligament in-juries were randomly assigned to receive either the new three-phase CM external treatment combined with the POLICE(pro-tect,optimal loading,ice,compression,elevation)treatment(observation group)or the POLICE treatment(control group),with 32 cases in each group.The observation group consisted of 17 males and 15 females,with an average age of(30.59±3.10)years old ranging from 25 to 36 years old,while the control group included 14 males and 18 females,with an average age of(30.03±3.19)years old ranging from 24 to 37 years old.Visual analogue scale(VAS)evaluation and Figure of 8 measurement were used to evaluate the degree of ankle joint pain and swelling of the subjects at the initial enrollment and after 1 week and sixth weeks of treatment.At the same time,the American Orthopaedic Foot and Ankle Society(AOFAS)and Karlsson Ankle Function Score System were used to evaluate the improvement of ankle joint function in patients at all stages.MRI imaging was employed to observe the degree of biological healing of the anterior talofibular ligament,with the signal to noise ratio(SNR)in-dicating the level of healing.A lower SNR suggests better ligament healing,as it represents lower water content in the ligament.Results All patients completed a 6-week follow-up.There was no significant difference in VAS,AOFAS score and Karlsson score between the two groups before treatment(P＞0.05).After 1 week and 6 weeks of treatment,the VAS,AOFAS score and Karlsson score of the two groups were significantly improved(P＜0.05).After 1 week of treatment,the VAS score of the obser-vation group(3.21±0.87)was lower than that of the control group(4.21±1.50),and the difference was statistically significant(P＜0.05).After 1 weeks of treatment,the AOFAS and Karlsson scores[(50.84±4.70)points,(49.97±4.00)points]of the ob-servation group were higher than those[(46.91±5.56)points,(46.66±5.36)points]of the control group(P＜0.05).MRI images showed that after 6 weeks of treatment,the SNR value of the observation group was significantly lower than that of the control group,and the difference was statistically significant(SNR of the observation group was 75.25±16.59,the contral gruop was 85.81±15.55),(P＜0.05).Conclusion Compared with the control group,the new three-phase CM external treatment is signifi-cantly effective in reducing pain and swelling,enhancing ligament repair quality,and promoting functional recovery of the an-kle joint in patients with acute lateral malleolar ligament injuries.

The main components and working principle of the negative pressure isolation treatment equipment were described,and the classification and application scopes of the negative pressure isolation treatment equipment from foreign countries and China were reviewed.The structure,key technical parameters and characteristics of different types of negative pressure isolation treatment equipment were analyzed under different conditions.The problems of the negative pressure isolation treatment equipment were analyzed,and it's pointed out it would be enhanced in component simplification,comfort,intelligence and multifunctionality.[Chinese Medical Equipment Journal,2024,45(2):97-104]

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]