BACKGROUND:Cervical disc herniation can cause pain in the neck and shoulder area,as well as radiating pain in the upper limbs.The incidence rate is increasing year by year and tends to affect younger individuals.Fully understanding the biomechanical characteristics of the cervical spine in adolescents is of great significance for preventing and delaying the onset of cervical disc herniation in this age group. OBJECTIVE:To reconstruct cervical spine models for both healthy adolescents and adolescent patients with cervical disc herniation utilizing finite element analysis techniques,to analyze the motion range of the C1-T1 cervical vertebrae as well as the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and the cartilage of the small joints. METHODS:A normal adolescent's cervical spine and an adolescent patient with cervical disc herniation were selected in this study.The continuous scan cervical spine CT raw image data were imported into Mimics 21.0 in DICOM format.The C1-T1 vertebrae were reconstructed separately.Subsequently,the established models were imported into the 3-Matic software for disc reconstruction.The perfected models were then imported into Hypermesh software for meshing of the vertebrae,nucleus pulposus,annulus fibrosus,and ligaments,creating valid geometric models.After assigning material properties,the final models were imported into ABAQUS software to observe the joint motion range of the C1-C7 cervical vertebrae segments under different conditions,and to analyze the biomechanical characteristics of the annulus fibrosus,nucleus pulposus,endplates,and small joint cartilage of each cervical spine segment. RESULTS AND CONCLUSION:(1)In six different conditions,the joint motion range of the C1 vertebra in the cervical spine models of both normal adolescent and adolescent patient with cervical disc herniation was higher than that of the other vertebrae.Additionally,the joint motion range of each cervical spine segment in normal adolescent was greater than that in adolescent patient with cervical disc herniation.(2)In the cervical spine model of normal adolescent,the maximum stress values in the annulus fibrosus and nucleus pulposus were found on the left side during C2-3 flexion conditions(0.43 MPa and 0.17 MPa,respectively).In the cervical spine model of adolescent patient with cervical disc herniation,the maximum stress values were found on the left side during C7-T1 flexion conditions(0.54 MPa and 0.18 MPa,respectively).(3)In the cervical spine model of normal adolescent,the maximum stress value on the endplate was found on the left side of the upper endplate of C3 during flexion conditions(1.46 MPa).In the model of adolescent patient with cervical disc herniation,the maximum stress value on the endplate was found on the left side of the lower endplate of C7 during flexion conditions(1.32 MPa).(4)In the cervical spine model of normal adolescent,the maximum stress value in the small joint cartilage was found in the C2-3 left rotation conditions(0.98 MPa).In adolescent patient with cervical disc herniation,the stress in the small joint cartilage significantly increased under different conditions,especially in C1-2,with the maximum stress found during left flexion(3.50 MPa).(5)It is concluded that compared to normal adolescent,adolescent patient with cervical disc herniation exhibits altered cervical curvature and a decrease in overall joint motion range in the cervical spine.In adolescent with cervical disc herniation,there is a significant increase in stress on the annulus fibrosus,nucleus pulposus,and endplates in the C7-T1 segment.The stress on the left articular cartilage of the C1-2 is notable.Abnormal cervical curvature may be the primary factor causing these stress changes.

Lactylation (Kla), a protein post-translational modification characterized by the covalent conjugation of lactyl groups to lysine residues in proteins, is widely present in living organisms. Since its discovery in 2019, it has attracted much attention for its role in regulating major pathological processes such as tumorigenesis, neurodegenerative diseases, and cardiovascular diseases. By mediating core biological processes such as signal transduction, epigenetic regulation, and metabolic homeostasis, lactylation contributes to disease progression. However, the lactylation donor lactyl-CoA has a low intracellular concentration, and the specific enzyme catalyzing lactylation is not yet clear, which has become an urgent issue in lactate research. A groundbreaking study in 2024 found that alanyl-transfer t-RNA synthetase 1/2 (AARS1/2), members of the aminoacyl-tRNA synthetase (aaRS) family, can act as protein lysine lactate transferases, modifying histones and metabolic enzymes directly with lactate as a substrate, without relying on the classical substrate lactyl-CoA, promoting a new stage in lactate research. Although exercise significantly increases lactate levels in the body and can induce changes in lactylation in multiple tissues and cells, the regulation of lactylation by exercise is not entirely consistent with lactate levels. Research has found that high-intensity exercise can induce upregulation of lactate at 37 lysine sites in 25 proteins of adipose tissue, while leading to downregulation of lactate at 27 lysine sites in 22 proteins. The level of lactate is not the only factor regulating lactylation through exercise. We speculate that the lactate transferase AARS1/2 play an important role in the process of lactylation regulated by exercise, and AARS1/2 should also be regulated by exercise. This review introduces the molecular biology characteristics, subcellular localization, and multifaceted biological functions of AARS, including its canonical roles in alanylation and editing, as well as its newly identified lactate transferase activity. We detail the discovery of AARS1/2 as lactylation catalysts and the specific process of them as lactate transferases catalyzing protein lactylation. Furthermore, we discuss the pathophysiological significance of AARS in tumorigenesis, immune dysregulation, and neuropathy, with a focus on exploring the expression regulation and possible mechanisms of AARS through exercise. The expression of AARS in skeletal muscle regulated by exercise is related to exercise time and muscle fiber type; the skeletal muscle AARS2 upregulated by long-term and high-intensity exercise catalyzes the lactylation of key metabolic enzymes such as pyruvate dehydrogenase E1 alpha subunit (PDHA1) and carnitine palmitoyltransferase 2 (CPT2), reducing exercise capacity and providing exercise protection; physiological hypoxia caused by exercise significantly reduces the ubiquitination degradation of AARS2 by inhibiting its hydroxylation, thereby maintaining high levels of AARS2 protein and exerting lactate transferase function; exercise induced lactate production can promote the translocation of AARS1 cytoplasm to the nucleus, exert lactate transferase function upon nuclear entry, regulate histone lactylation, and participate in gene expression regulation; exercise induced lactate production promotes direct interactions between AARS and star molecules such as p53 and cGAS, and is widely involved in the occurrence and development of tumors and immune diseases. Elucidating the regulatory mechanism of exercise on AARS can provide new ideas for improving metabolic diseases and promote health through exercise.

Drug-induced liver injury(DILI)is a common adverse drug reaction in clinical practice,which can lead to acute liver failure and even death in severe cases.In recent years,with the continuous introduction of new drugs and the expansion of their usage,the incidence and mortality rates of DILI have shown an upward trend,posing significant challenges to public health and clinical treatment.Macrophages,as a crucial component of the innate immune system,exhibit high plasticity and heterogeneity.They can polarize into pro-inflammatory M1 type or anti-inflammatory M2 type in response to microenvironmental signals.Research has demonstrated that macrophage polarization plays a central regulatory role in the occurrence and progression of DILI by influencing various processes such as inflammatory responses,cell apoptosis,and tissue repair.This review focuses on elucidating the regulatory mechanisms and roles of macrophage polarization in DILI,providing a theoretical framework for developing precise immunotherapeutic strategies.

Objective To investigate the status of population dynamics and distribution changes of Aedes aegypti in Guangdong Province.Methods Continuous monitoring was conducted from May 2018 to July 2024 in Wushi Town and Qishui Town,Leizhou City,Zhanjiang City,Guangdong Province.Additionally,a survey of the distribution of Ae.aegypti along the Leizhou Peninsula coast was carried out.Results The density of Ae.aegypti in Zhanjiang showed a gradual decline from 2018 to 2024.The last detection of adult Ae.aegypti in Wushi Town was in September 2021,and the last larva was found in October 2023.No Ae.aegypti was detected in Qishui Town during surveys from 2021 to 2024.A survey of 18 coastal villages in the Leizhou Peninsula revealed no detections of Ae.aegypti.Conclusions This study provides a basis for understanding the distribution and population density fluctuations of Ae.aegypti,assessing its invasion risk,and scientifically conducting relevant prevention and control efforts.

Post-traumatic stress disorder (PTSD) is a relatively common but complex mental illness with a range of diverse risk factors. Typical symptoms include the re-experience or avoidance of traumatic events, cognitive impairment, and hypervigilance. While the exact pathogenesis of PTSD is unclear, many studies indicate that epigenetic regulation plays a key role in its development. Specifically, numerous studies have indicated that the levels of histone acetylation and methylation, DNA methylation, and noncoding RNA are altered in PTSD patients. Further to this, natural products have been found to achieve epigenetic regulation of PTSD by regulating the expression of epigenetic enzymes, long noncoding RNA (lncRNA), and miRNA, thereby playing a role in improving PTSD symptoms. To date, however, no epigenetic regulation related drugs have been used in the treatment of PTSD. Furthermore, while natural products that can epigenetically regulate PTSD have received increasing levels of attention, there have not yet been any systematic reports on the topic. Here, we summarized the roles and mechanisms of natural products in the epigenetic regulation of PTSD, providing a novel and unique perspective that will help to guide the development and application of new PTSD treatments.

Objective The effect of intra-aortic balloon counterpulsation combined with recombinant human brain natriuretic peptide(rhBNP)treatment on ventricular remodeling after percutaneous coronary intervention(PCI)in elderly patients with acute anterior wall myocardial infarction.Methods A retrospective analysis was con-ducted on 66 elderly patients with acute anterior myocardial infarction who underwent emergency PCI in our hospital from January 2018 to June 2023.They were divided into a control group(n=32)who underwent PCI+rhBNP,and a study group(n=32)who underwent PCI+rhBNP+intra-aortic balloon counterpulsation.Blood pressure,lactic acid level,mechanical complications,ventricular remodeling,inflammatory factors,myocardial enzymology,ox-LDL level were detected and compared between the two groups.Results Before treatment,Lactic acid,diastolic blood pressure,systolic blood pressure,left ventricular end-systolic diameter(LVESD),left ventricular end-diastolic diameter(LVEDD),left ventricular posterior wall thickness(LVPWT),left ventricular remodeling index(LVRI),left ventricular ejection fraction(LVEF),homocysteine(Hcy),interleukin-6(IL-6)and myocardial troponin were compared between the two groups.Myocardial troponin T(cTnT),lactate dehydrogenase(LDH),creatine kinase isoenzyme(CK-MB),oxidized low density lipoprotein(ox-LDL)levels(P>0.05);At 3 months follow-up after discharge,the levels of lactic acid,LVESD,LVEDD,LVPWT,LVRI,Hcy,IL-6,cTnT,LDH,CK-MB and ox-LDL were decreased,and the levels were lower in the study group,and the levels of diastolic blood pressure,systolic blood pressure and LVEF were increased,and the levels were higher in the study group(P<0.05).The pro-portion of mechanical complications between the two groups before and after treatment were compared(P>0.05).Conclusion In elderly patients with acute anterior myocardial infarction after emergency PCI,intra-aortic balloon counterpulsation combined with rhBNP could alleviate ventricular remodeling,myocardial injury,reduce inflamma-tory injury,improve oxidative stress response,and regulate tissue perfusion.

BACKGROUND:The highest incidence of spinal fracture is in the thoracolumbar segment,and its symptoms are back pain,posterior convexity deformity,activity limitation,or with spinal cord nerve injury causing lower limb pain,numbness,and even paraplegia and other complications.The finite element method is a digital computer modeling technique,which can simulate the physical model and carry out force analysis realistically.OBJECTIVE:To review the application of finite element method in thoracolumbar spine fractures.METHODS:We searched the Chinese and English literature databases PubMed,Web of Science,and CNKI for relevant literature on the application of the finite element analysis method in spinal thoracolumbar fracture published before March 2024.The search terms in Chinese and English were:finite element analysis methods,biomechanical phenomena,stress analysis,thoracolumbar fractures,spinal fractures.Finally,55 papers were included.RESULTS AND CONCLUSION:(1)The exploration of thoracolumbar fractures caused by different etiologies(osteoporotic,traumatic,and pathological)through the finite element method is conducive to a deeper understanding of the biomechanics of various types of thoracolumbar fractures,and to improve the individualized and fine-tuned treatment of thoracolumbar fractures.(2)The finite element analysis of a single sample or a small number of samples has the chance,and a larger number of samples are required for the future finite element analysis to reduce the chance caused by the sample.(3)The rigid structure of bones alone cannot meet the biomechanical working conditions of the integrity of the physical object,and future finite element models need to incorporate all the structures of the physical object(e.g.,soft tissues,such as muscles and ligaments)as far as possible.(4)The finite element method has been used in more studies on osteoporotic and traumatic thoracolumbar spine fractures,which will need to be more in-depth in the future,and less in the field of pathologic thoracolumbar fractures,which has a wider scope for future research.

BACKGROUND:The asymmetrical biomechanical environment of adolescent idiopathic scoliosis can lead to further wedge deformation of the vertebral body,which may affect cardiopulmonary function and compress nerves in severe cases.Adolescent idiopathic scoliosis with different degrees of scoliosis should be treated with exercise,bracing,and surgery.However,the mechanical mechanism of selecting an orthopedic approach remains unclear due to the individual variability of patients.OBJECTIVE:To investigate the biomechanical mechanism of different orthopedic modalities for the treatment of adolescent idiopathic scoliosis to provide a basis for clinical selection of treatment modalities based on the spine model of adolescent idiopathic scoliosis patients.METHODS:Based on the CT images of an adolescent idiopathic scoliosis patient,a scoliosis model(C7-L5)was reconstructed in Mimics software in three dimensions,and lateral thrust force was applied at the T8/T9 thorax and vertical distraction force was applied over the C7 vertebra with the magnitude of 20,40,60,80,100,and 120 N.The intervertebral disc stress and vertebral displacement in concave and convex sides,and Cobb angle of the spine were analyzed under two orthopedic modalities.RESULTS AND CONCLUSION:(1)With lateral thrust,there was no significant change in the C7T1-T7T8 intervertebral disc.The concave and convex stress of T7T8-L4L5 segment decreased first and then increased with the increase of lateral thrust force.The correction effect of lateral thrust on the segment near T8T9 was obvious and weakened with the extension of the segment to the cephalic and caudal ends.At 120 N of lateral thrust,the thoracic Cobb angle changed from 53.2° to 32.5° and the lumbar Cobb angle changed from 50.2° to 43.9°.(2)With the vertical distraction,the thoracic intervertebral disc stresses first decreased and then increased,and all the lumbar disc stresses decreased.The C7 displacement was the most obvious,and the correction effect gradually diminished with the segment extended to the caudal end.At a vertical distraction force of 120 N,the thoracic Cobb angle changed from 53.2° to 39.4° and the lumbar Cobb angle changed from 50.2° to 47.6°.(3)It is concluded that both orthopedic modalities provide improvement in the degree of scoliosis,with the thoracic correction being greater than the lumbar correction.Also,the asymmetric stress distribution on the concave and convex sides is improved,which contributes to normal bone growth.A vertical distraction approach is appropriate for larger Cobb angles,and a lateral thrust approach is appropriate for smaller Cobb angles.The results of this study help to understand the mechanism of spinal orthosis and provide a theoretical basis for the choice of orthopedic approach.

Objective To investigate the relationship between brain white matter lesions (WML) and triglyceride glucose (TyG) index in non-diabetic elderly individuals based on magnetic resonance imaging. Methods A total of 523 non-diabetic elderly individuals aged ≥ 60 years were selected from Jinan, Shandong Province, China from June 2018 to December 2019. According to the quartiles of TyG index, there were 133 participants in the first quartile (Q1) group, 127 in the second quartile (Q2) group, 132 in the third quartile (Q3) group, and 131 in the fourth quartile (Q4) group. All participants underwent brain magnetic resonance imaging to evaluate paraventricular, deep, and total WML volumes, as well as Fazekas scores. Results Compared with Q1, Q2, and Q3 groups, Q4 group showed significant increase in periventricular, deep, and total WML volumes (P < 0.05). The proportion of participants with a Fazekas score ≥ 2 in the periventricular, deep, and total WML was higher in the Q4 group compared with the Q1 and Q2 groups (P < 0.05). The proportion of participants with a Fazekas score ≥ 2 in deep WML was higher in Q4 group than in Q3 group (P < 0.05). TyG index was significantly positively correlated with periventricular, deep, and total WML volumes (r = 0.401, 0.405, and 0.445, P < 0.001). After adjusting for confounding factors, TyG index was still significantly positively correlated with periventricular, deep, and total WML volumes (P < 0.001). Logistic regression analysis showed that compared with Q1 group, the risk of Fazekas score ≥ 2 in periventricular WML was 1.950-fold (95% confidence interval [CI]: 1.154-3.294, P = 0.013) in Q3 group and 3.411-fold (95% CI: 1.984-5.863, P < 0.001) in Q4 group, the risk of Fazekas score ≥ 2 in total WML was 2.529-fold (95%CI: 1.444-4.430, P = 0.001) in Q3 group and 4.486-fold (95%CI: 2.314-8.696, P < 0.001) in Q4 group. The risk of Fazekas score ≥ 2 in deep WML was 2.953-fold (95%CI: 1.708-5.106, P < 0.001) in Q4 group compared with Q1 group. Conclusion Increased TyG index is an independent risk factor for WML in non-diabetic elderly individuals.

OBJECTIVE: This study reports the first imported case of Lassa fever (LF) in China. Laboratory detection and molecular epidemiological analysis of the Lassa virus (LASV) from this case offer valuable insights for the prevention and control of LF. METHODS: Samples of cerebrospinal fluid (CSF), blood, urine, saliva, and environmental materials were collected from the patient and their close contacts for LASV nucleotide detection. Whole-genome sequencing was performed on positive samples to analyze the genetic characteristics of the virus. RESULTS: LASV was detected in the patient's CSF, blood, and urine, while all samples from close contacts and the environment tested negative. The virus belongs to the lineage IV strain and shares the highest homology with strains from Sierra Leone. The variability in the glycoprotein complex (GPC) among different strains ranged from 3.9% to 15.1%, higher than previously reported for the seven known lineages. Amino acid mutation analysis revealed multiple mutations within the GPC immunogenic epitopes, increasing strain diversity and potentially impacting immune response. CONCLUSION The case was confirmed through nucleotide detection, with no evidence of secondary transmission or viral spread. The LASV strain identified belongs to lineage IV, with broader GPC variability than previously reported. Mutations in the immune-related sites of GPC may affect immune responses, necessitating heightened vigilance regarding the virus.
Humans ; China/epidemiology* ; Genome, Viral ; Lassa Fever/virology* ; Lassa virus/classification* ; Molecular Epidemiology ; Phylogeny