BACKGROUND:Degenerative scoliosis is defined as a condition that occurs in adulthood with a coronal cobb angle of the spine>10° accompanied by sagittal deformity and rotational subluxation,which often produces symptoms of spinal cord and nerve compression,such as lumbar pain,lower limb pain,numbness,weakness,and neurogenic claudication.The finite element method is a mechanical analysis technique for computer modelling,which can be used for spinal mechanics research by building digital models that can realistically restore the human spine model and design modifications. OBJECTIVE:To review the application of finite element method in the etiology and treatment of degenerative scoliosis. METHODS:The literature databases CNKI,PubMed,and Web of Science were searched for articles on the application of finite element method in degenerative scoliosis published before October 2023.Search terms were"finite element analysis,biomechanics,stress analysis,degenerative scoliosis,adult spinal deformity"in Chinese and English.Fifty-four papers were finally included. RESULTS AND CONCLUSION:(1)The biomechanical findings from the degenerative scoliosis model constructed using the finite element method were identical to those from the in vivo experimental studies,which proves that the finite element method has a high practical value in degenerative scoliosis.(2)The study of the etiology and treatment of degenerative scoliosis by the finite element method is conducive to the prevention of the occurrence of the scoliosis,slowing down the progress of the scoliosis,the development of a more appropriate treatment plan,the reduction of complications,and the promotion of the patients'surgical operation.(3)The finite element method has gradually evolved from a single bony structure to the inclusion of soft tissues such as muscle ligaments,and the small sample content is increasingly unable to meet the research needs.(4)The finite element method has much room for exploration in degenerative scoliosis.

Objective To investigate the levels of radionuclides in food in Beijing, China, and assess the committed effective dose to local residents from food intake. Methods From 2021 to 2022, a total of 65 food samples across 7 categories were collected in Beijing. The activity concentrations of radionuclides, including ¹³⁷Cs, ²¹⁰Pb, ²³⁸U, ²²⁸Ra, ²²⁶Ra, ⁴⁰K, ⁹⁰Sr, ²¹⁰Po, ³H and ¹⁴C, were measured using gamma spectrometry and radiochemical methods. By combining the monitoring results with dietary consumption data of Beijing residents and the internal dose coefficients for Chinese reference adult phantom, the committed effective dose was estimated. Results The levels of radionuclides in food in Beijing were within the normal background range, consistent with related surveys in China and abroad, with activity concentrations below national standard limits. No significant differences were found in the activity concentrations of ¹³⁷Cs, ²³⁸U, ²²⁸Ra, ²²⁶Ra and ⁴⁰K between food samples collected from key areas and those from control areas (P > 0.05). The committed effective doses calculated according to internal dose coefficients for Chinese reference adult male phantom and GB 18871-2002 were 0.26 mSv and 0.19 mSv, respectively. Based on the Chinese reference adult male phantom, the majority of the committed effective dose was attributed to ²¹⁰Pb (45.1%), ²²⁸Ra (37.1%), ²¹⁰Po (12.3%), and ²²⁶Ra (4.7%). Conclusion The levels of radionuclides in food in Beijing fluctuated within the background range, resulting in a low radiation dose burden to the population.

In order to clarify the effects of drought stress training on the quality and drought resistance of Codonopsis pilosula, this study used PEG to simulate drought stress and employed potting with water control for the drought stress training of C. pilosula plants. The polysaccharide content, secondary metabolites, antioxidant system, and photosynthetic pigment system of C. pilosula after drought stress training were analyzed. The results showed that the content of fructans in the root of C. pilosula increased after two rounds of drought stress treatment, and it was significantly higher than that of the control group. The accumulation of fructans in the root of C. pilosula showed an upward trend during the rehydration treatment. The content of lobetyolin and tangshenoside Ⅰ increased after drought stress treatment compared with that of the control group. The rehydration treatment caused first increasing and then decreasing in the content of lobetyolin, while it had no significant effect on the tangshenoside Ⅰcontent. The content of photosynthetic pigments decreased after drought stress treatment, and it gradually increased during the first round of rehydration and the second round of rehydration. Moreover, the increase was faster in the second round of rehydration than in the first round of rehydration. The content of the peroxidation product malondialdehyde(MDA) and the activities of superoxide dismutase(SOD), peroxidase(POD), and catalase(CAT) increased after drought stress treatment compared with those of the control group, and they showed a tendency of decreasing during rehydration. Moreover, the decrease was faster in the second round of rehydration than in the first round of rehydration. When the plants of C. pilosula after drought stress training were again subjected to severe drought stress, the wilting rate decreased significantly, and the biomass increases significantly. This study showed that the drought stress training could promote the accumulation of polysaccharides and secondary metabolites in the root of C. pilosula. When encountering drought stress again, C. pilosula plants could quickly regulate the antioxidant system and delay the decomposition of chlorophyll to respond to drought stress. The findings provide a theoretical basis for the ecological cultivation of C. pilosula in arid and semi-arid areas.
Codonopsis/growth & development* ; Droughts ; Polysaccharides/metabolism* ; Stress, Physiological ; Water/metabolism* ; Antioxidants/metabolism* ; Photosynthesis ; Drought Resistance

PURPOSE: To judge the injury mode and injury severity of the real human body through the measured values of anthropomorphic test devices (ATD) injury indices, the mapping relationship of lumbar injury between ATD and human body model (HBM) was explored. METHODS: Through the ATD model and HBM simulation, the mapping relationship of lumbar injury between the 2 subjects was explored. The sled environment consisted of a semi-rigid seat with an adjustable seatback angle and a 3-point seat belt system with a seatback-mounted D-ring. Three seatback recline states of 25°, 45°, and 65° were designed, and the seat pan angle was maintained at 15°. A 23 g, 47 km/h pulse was used. The validity of the finite element model of the sled was verified by the comparison of ATD simulation and test results. ATD model was the test device for human occupant restraint for autonomous vehicles (THOR-AV) dummy model and HBM was the total human model for safety (THUMS) v6.1. The posture of the 2 models was adjusted to adapt to the 3 seat states. The lumbar response of THOR-AV and the mechanical and biomechanical data on L1 - L5 vertebrae of THUMS were output, and the response relationship between THOR-AV and THUMS was descriptive statistically analyzed. RESULTS: Both THOR-AV and THUMS were submarined in the 65° seatback angle case. With the change of seatback angle, the lumbar spine axial compression force (F_z) of THOR-AV and THUMS changed in the similar trend. The maximum F_z ratio of THOR-AV to THUMS at 25° and 45° seatback angle cases were 1.6 and 1.7. The flexion moment (M_y) and the time when the maximum M_y occurred in the 2 subjects were very different. In particular, the form of moment experienced by the L1 - L5 vertebrae of THUMS also changed. The changing trend of M_y measured by THOR-AV over time can reflect the changing trend of maximum stress of L1 and L2 of THUMS. CONCLUSION The F_z of ATD and HBM presents a certain proportional relationship, and there is a mapping relationship between the 2 subjects on F_z. The mapping function can be further clarified by applying more pulses and adopting more seatback angles. It is difficult to map M_y directly because they are very different in ATD and HBM. The M_y of ATD and stress of HBM lumbar showed a similar change trend over time, and there may be a hidden mapping relationship.
Humans ; Lumbar Vertebrae/injuries* ; Finite Element Analysis ; Biomechanical Phenomena ; Manikins ; Spinal Injuries/physiopathology*

PURPOSE: To investigate the incidence and influencing factors of bone loss in patients with spinal cord injury (SCI). METHODS: A retrospective case-control study was conducted. Patients with SCI in our hospital from January 2019 to March 2023 were collected. According to the correlation between bone mineral density (BMD) at different sites, the patients were divided into the lumbar spine group and the hip joint group. According to the BMD value, the patients were divided into the normal bone mass group (t > -1.0 standard deviation) and the osteopenia group (t ≤ -1.0 standard deviation). The influencing factors accumulated as follows: gender, age, height, weight, cause of injury, injury segment, injury degree, time after injury, start time of rehabilitation, motor score, sensory score, spasticity, serum value of alkaline phosphatase, calcium, and phosphorus. The trend chart was drawn and the influencing factors were analyzed. SPSS 26.0 was used for statistical analysis. Correlation analysis was used to test the correlation between the BMD values of the lumbar spine and bilateral hips. Binary logistic regression analysis was used to explore the influencing factors of osteoporosis after SCI. p < 0.05 was considered statistically significant. RESULTS: The incidence of bone loss in patients with SCI was 66.3%. There was a low concordance between bone loss in the lumbar spine and the hip, and the hip was particularly susceptible to bone loss after SCI, with an upward trend in incidence (36% - 82%). In this study, patients with SCI were divided into the lumbar spine group (n = 100) and the hip group (n = 185) according to the BMD values of different sites. Then, the lumbar spine group was divided into the normal bone mass group (n = 53) and the osteopenia group (n = 47); the hip joint group was divided into the normal bone mass group (n = 83) and the osteopenia group (n = 102). Of these, lumbar bone loss after SCI is correlated with gender and weight (p = 0.032 and < 0.001, respectively), and hip bone loss is correlated with gender, height, weight, and time since injury (p < 0.001, p = 0.015, 0.009, and 0.012, respectively). CONCLUSIONS The incidence of bone loss after SCI was high, especially in the hip. The incidence and influencing factors of bone loss in the lumbar spine and hip were different. Patients with SCI who are male, low height, lightweight, and long time after injury were more likely to have bone loss.
Humans ; Spinal Cord Injuries/complications* ; Male ; Female ; Retrospective Studies ; Incidence ; Adult ; Bone Density ; Middle Aged ; Case-Control Studies ; Osteoporosis/etiology* ; Lumbar Vertebrae ; Bone Diseases, Metabolic/etiology* ; Aged ; Risk Factors

OBJECTIVES: To investigate the clinical sub-phenotype (SP) of pediatric acute kidney injury (AKI) and their association with clinical outcomes. METHODS: General status and initial values of laboratory markers within 24 hours after admission to the pediatric intensive care unit (PICU) were recorded for children with AKI in the derivation cohort (n=650) and the validation cohort (n=177). In the derivation cohort, a least absolute shrinkage and selection operator (LASSO) regression analysis was used to identify death-related indicators, and a two-step cluster analysis was employed to obtain the clinical SP of AKI. A logistic regression analysis was used to develop a parsimonious classifier model with simplified metrics, and the area under the curve (AUC) was used to assess the value of this model. This model was then applied to the validation cohort and the combined derivation and validation cohort. The association between SPs and clinical outcomes was analyzed with all children with AKI as subjects. RESULTS: In the derivation cohort, two clinical SPs of AKI (SP1 and SP2) were identified by the two-step cluster analysis using the 20 variables screened by LASSO regression, namely SP_d1 group (n=536) and SP_d2 group (n=114). The simplified classifier model containing eight variables (P<0.05) had an AUC of 0.965 in identifying the two clinical SPs of AKI (P<0.001). The validation cohort was clustered into SP_v1 group (n=156) and SP_v2 group (n=21), and the combined derivation and validation cohort was clustered into SP1 group (n=694) and SP2 group (n=133). After adjustment for confounding factors, compared with the SP1 group, the SP2 group had significantly higher incidence rates of multiple organ dysfunction syndrome and death during the PICU stay (P<0.001), and SP2 was significantly associated with the risk of death within 28 days after admission to the PICU (P<0.001). CONCLUSIONS This study establishes a parsimonious classifier model and identifies two clinical SPs of AKI with different clinical features and outcomes.The SP2 group has more severe disease and worse clinical prognosis.
Humans ; Acute Kidney Injury/diagnosis* ; Prognosis ; Male ; Female ; Child ; Child, Preschool ; Phenotype ; Infant ; Logistic Models ; Adolescent

Objective : To investigate the effect of laminarin(LAM) on nonproliferative diabetes retinopathy by high throughput sequencing(RNA-seq). Methods : The diabetes model was established by intraperitoneal injection of streptozotocin(STZ), and the effect of LAM on diabetic mice was observed.C57BL/6 mice were randomly divided into three groups: Control group, Model group, and LAM group, with 8 mice in each group. After 8 weeks of modeling, the LAM group received a 4-week intraperitoneal injection of LAM treatment. Changes in blood glucose and body weight of the three groups of mice were recorded, HE staining was performed to examine retinal lesions, and RNA-seq was used to identify differentially expressed genes(DEGs) in diabetic retinopathy(DR) under the action of STZ and LAM. Results : STZ successfully established the model of DR, and LAM reduced the blood sugar in diabetic mice to a certain extent and improved the pathological morphology of retinal structural looseness in diabetic mice. After RNA-seq analysis of DEGs, it was found that there were a total of 214 DEGs in the retina of the Model group mice compared to the Control group. Enrichment analysis revealed that DR could exacerbate the lesions through the PI3K Akt signaling pathway. There were a total of 42 DEGs in the retina of the Model group and LAM group mice, and enrichment showed that LAM improved the lesions through the neutrophil extracellular trap pathway. Early growth response factor 1(Egr1), FBJ osteosarcoma oncogene(Fos), nuclear receptor subfamily 4A member 1(Nr4a1), and salt-induced kinase 1(Sik1) were regulated by STZ, and LAM significantly regulated their expression, which might be closely related to LAM′s treatment of diabetic retinopathy. Conclusion DEGs can exacerbate the severity of diabetic retinopathyviathe PI3K-Akt signaling pathway. LAM can mitigate diabetic retinopathyviathe neutrophil extracellular trap pathway. Egr1, Fos, Nr4a1, and Sik1 are key genes involved in LAM treatment of STZ-induced DR.

Objective:To study the molecular mechanism of functional defect of protein C (PC) caused by point mutations of human protein C gene (PROC) N355S,G392E and T314A. Methods:The wild-type and mutant plasmids (PCWT,PCN355S,PCG392E,PCT314A) of PROC gene were constructed and transiently transfected into HEK293 cells. The expression of mutant proteins in vitro were tested. The mRNA level changes of wild-type and mutant PC after 24 h of transfection were detected by real-time PCR. Western blot and ELISA were used to detect the changes of intracellular and extracellular protein levels of wild-type and mutant PC. The supernatant of cells transfected for 24-48 h was concentrated by ultrafiltration. The protein in the concentrated solution was quantified,and PC activation and enzyme kinetics tests were performed. Clustal Omega multiple sequence alignment was used to analyze the conservation of amino acid mutation sites. The effect of mutation on PC protein structure was analyzed by PyMOL software. Results:The relative expression abundances of PROC mRNA in PCN355S,PCG392E and PCT314A groups were 1.14±0.46,0.96±0.08 and 1.08±0.17,respectively,and there were no significant differences compared with 1.02±0.24 in PCWT group (P>0.05). Western blot analysis of the lysates of transfected cells showed that the content of PCT314A recombinant protein slightly decreased and the band became relatively lighter. The ELISA results of the concentrated cell culture supernatants showed that the PC:Ag levels of PCN355S and PCG392E were 98.8％±2.4％ and 101.4％±3.1％,respectively,with no significant differences compared with PCWT,while PCT314A decreased compared with PCWT (PC:Ag:88.6％±3.2％) (P<0.05). The results of enzyme kinetics test showed that APCN355S (Km=338.3±43.2,Vmax=2.015±0.12),APCG392E (Km=292.2±28.4,Vmax=1.893±0.07) and APCT314A (Km=299.5±24.6,Vmax=1.775±0.06) showed an increase in Km and a decrease in Vmax compared with APCWT (Km=238.2±4.58,Vmax=3.205±0.06). Multiple sequence alignment suggested that the three mutations be highly conservative in different species. The structural model suggested that the amino acid substitutions of N355S,G392E and T314A mutations collide with the surrounding amino acid groups,causing distortion of the surrounding structure,which may have adverse effects on the folding and biological function of PC. Conclusion:The N355S,G392E and T314A mutations in the PROC gene cause functional defects in PC by weakening the binding between PC and substrate. These three mutations have caused serious spatial collisions in the protein structure,affecting the folding of PC and the reactivity of active sites.

Objective:To analyze the application value of MCV,MCH and HbA2 in screening for thalassemia in the population of childbearing age in Quanzhou area,and to determine the optimal screening cut-off value of relevant indicators in this area. Methods:2725 couples of childbearing age were included in the study and underwent routine blood test,capillary hemoglobin electrophoresis,and α and β thalassemia gene test. Statistical methods were used to analyze the distribution of thalassemia genotypes,and compare the performance of MCV,MCH,and HbA2 in screening various types of thalassemia. According to the ROC curve,the best cut-off values of MCV,MCH and HbA2 in screening for thalassemia in this area were determined. Results:In this study,a total of 1801 thalassemia carriers were detected,including 1341 cases of α-thalassemia,420 cases of β-thalassemia,and 40 cases of αβ compound thalassemia. The most common genotypes of α-thalassemia and β-thalassemia were--SEA/αα and β654/βN,respectively. ROC curves were drawn to evaluate the performance of MCV,MCH and HbA2 in screening for α-thalassemia,mild β-thalassemia,αβ compound thalassemia,silent α-thalassemia,mild α-thalassemia,and intermediate α-thalassemia. The maximum areas under the curves (AUC) were 0.747,0.865,0.724,0.486,0.812,0.841;0.747,0.846,0.703,0.479,0.796,0.903;0.613,0.980,0.909,0.465,0.674,0.996,respectively;and the best cut-off values corresponding to the three screening indicators were 76.15fl,71.95fl,77.35fl,86.15fl,75.41fl,61.15fl;24.35pg,21.51pg,25.45pg,28.65pg,24.01pg,20.51pg;2.45％,3.05％,3.55％,3.25％,2.45％,1.65％,respectively. Conclusion:The levels of MCV,MCH and HbA2 are correlated with the phenotype of thalassemia,and the detection of these indicators is of great significance for the prevention and control of thalassaemia.

Objective:To investigate the clinical effect of extraperitoneal robot-assisted laparoscopic modified Y-V plasty(LMYVP)in the treatment of refractory bladder neck contracture(BNC).Methods:We retrospectively analyzed the clinical data on 10 cases of refractory BNC after transurethral resection of the prostate between September 2020 and January 2023,all with a history of recurrent urethral dilatation and at least two failures in transurethral surgical treatment of scarring.After definite diagnosis and re-moval of some of the scar tissues to flatten the elevated bladder neck under the cystoscope,we performed robot-assisted LMYVP using the da Vinci Si robotic system and a four-port extraperitoneal approach.The surgical procedure involved an inverted T-shaped incision in the bladder neck and urethral stricture ring,an inverted V-shaped excision of the scar area at the 3-9 o'clock position on the ventral side of the prostatic urethra,continuous full-layer suturing of the bladder neck and inverted V-shaped urethra with 3-0 barbed thread,and indwelling of an F20 silicone catheter for 2 weeks.At 3 months after surgery,we performed cystoscopic examination,measured the maximum urinary flow rate(Qmax),and obtained the IPSS and quality of life(QOL)scores of the patients.Results:Operations were successfully completed in all the cases.At 3 months after surgery,the patients showed significantly increased Qmax([3.65±1.27]vs[20.3±1.77]ml/s,P＜0.05),IPSS(5.9±2.02 vs 30±1.15,P＜0.05)and QOL score(1.3±0.95 vs 5.2±0.79,P＜0.05)compared with the baseline.Cystoscopy revealed a wide and flat bladder neck with good survival and hemody-namics of the bladder flap.All the patients met the criteria for clinical cure at a median follow-up of 13.2 months.Conclusion:Extraper-itoneal robot-assisted LMYVP provides a new strategy for urinary tract reconstruction in the management of refractory BNC,with the ad-vantages of minimal invasiveness,high efficiency and high success rate.