Objective:To investigate the risk factors associated with post-prematurity respiratory disease (PPRD) in very preterm infants.Methods:A prospective cohort study was conducted, enrolling 369 very preterm infants who were admitted to the neonatal intensive care unit of Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, within one week of birth from January 2019 to June 2023. Data on maternal and infant clinical characteristics, neonatal morbidities, and treatments during hospitalization were collected. The very preterm infants were divided into 2 groups based on whether they developed PPRD. Continuous variables were compared using Mann-Whitney U test, while categorical variables were compared using χ2 tests or continuity correction χ2 test. Multivariate Logistic regression analysis was used to identify the independent risk factors for PPRD in very preterm infants. Results:Among the 369 very preterm infants, 217 cases(58.8%) were male, with a gestational age of 30 (28, 31) weeks at birth and a birth weight of 1 320 (1 085, 1 590) g. Of these, 116 cases (31.4%) developed PPRD, while 253 cases (68.6%) did not. The very preterm infants in the PPRD group had a lower gestational age and lower birth weight (both, P<0.001). The PPRD group also had a higher proportion of males, lower Apgar scores at the 1 th minute after birth and the 5 th minutes after birth, a higher rate of born via cesarean delivery, and a higher incidence of bronchopulmonary dysplasia, more pulmonary surfactant treatment, longer durations of mechanical ventilation, longer total oxygen therapy, and lower Z-score for weight at discharge (all P<0.05). Multivariate Logistic regression analysis showed that gestational age ( OR=0.85, 95% CI 0.73-0.99, P=0.037), born via cesarean delivery ( OR=2.23, 95% CI 1.21-4.10, P=0.010), a duration of mechanical ventilation ≥7 days ( OR=2.51, 95% CI 1.43-4.39, P=0.001), and a Z-score for weight at discharge ( OR=0.82, 95% CI 0.67-0.99, P=0.040) were all independent risk factors for PPRD in very preterm infants. Conclusion:Very preterm infants with a small gestational age, born via cesarean section, mechanical ventilation ≥7 days, and a low Z-score for weight at discharge should be closely monitored for PPRD, and provided with standardized respiratory management after discharge.

BACKGROUND:Bone relies on the close connection between blood vessels and bone cells to maintain its integrity.Bones are in a physiologically hypoxic environment.Therefore,the study of angiogenesis and osteogenesis in hypoxic environment is closer to the microenvironment in vivo. OBJECTIVE:To explore the influence of Wenshen Tongluo Zhitong(WSTLZT)formula on H-type bone microvascular endothelial cell/bone marrow mesenchymal stem cell co-culture system in hypoxia environment and its related mechanism. METHODS:Enzyme digestion method and flow sorting technique were used to isolate and identify H-type bone microvascular endothelial cells.Mouse bone marrow mesenchymal stem cells were isolated and obtained by bone marrow adhesion method.H-type bone microvascular endothelial cell/bone marrow mesenchymal stem cell hypoxic co-culture system was established using Transwell chamber and anoxic culture workstation.WSTLZT formula powder was used to intervene in each group at a mass concentration of 50 and 100 μg/mL.The angiogenic function of H-type bone microvascular endothelial cells in the co-culture system was evaluated by scratch migration test and tube formation test.The osteogenic differentiation ability of bone marrow mesenchymal stem cells in the co-cultured system was evaluated by alkaline phosphatase staining and alizarin red staining.The protein and mRNA expression changes of PDGF/PI3K/AKT signal axis related molecules in H-type bone microvascular endothelial cells in the co-cultured system were detected by Western Blotting and q-PCR,respectively. RESULTS AND CONCLUSION:(1)Compared with the normal oxygen group,the scratch mobility and new blood vessel length of H-type bone microvascular endothelial cells were significantly higher(P<0.05);the osteogenic differentiation capacity of bone marrow mesenchymal stem cells was higher(P<0.05);the expression of PDGF/PI3K/AKT axis-related molecular protein and mRNA increased(P<0.05)in the hypoxia group.(2)Compared with the hypoxia group,scratch mobility and new blood vessel length were significantly increased in the H-type bone microvascular endothelial cells(P<0.05);bone marrow mesenchymal stem cells had stronger osteogenic function(P<0.05);the expression of PDGF/PI3K/AKT axis-related molecular proteins and mRNA further increased(P<0.05)after treatment with different dose concentrations of WSTLZT formula.These findings conclude that H-type angiogenesis and osteogenesis under hypoxia may be related to the PDGF/PI3K/AKT signaling axis,and WSTLZT formula may promote H-type vasculo-dependent bone formation by activating the PDGF/PI3K/AKT signaling axis,thereby preventing and treating osteoporosis.

BACKGROUND:Cardiac dysfunction due to spinal cord injury is an important factor of death in patients with spinal cord injury;however,the specific mechanism is still not clear.Therefore,revealing the mechanism of cardiac dysfunction in spinal cord injury patients is of great significance to improve their quality of life and survival rate. OBJECTIVE:To investigate the mechanism of luteolin in improving serum-induced myocardial cell death in spinal cord injury rats. METHODS:Allen's impact instrument was used to damage the spine T9-T11 of male SD rats to establish a spinal cord injury model meanwhile a sham operation group was set as the control group.The serum of rats of each group was collected.H9c2 cells were divided into a blank control group,a sham operated rat serum group,a spinal cord injury rat serum group and a luteolin pretreatment group.The cells in blank control group were only cultured with ordinary culture medium.The cells in the sham operated rat serum group were treated with medium containing 10%serum from sham operated rat.The cells in the spinal cord injury rat serum group were treated with medium containing 10%serum from spinal cord injury rat.The cells in the luteolin pretreatment group were precultured with a final concentration of 20 μmol/L luteolin for 4 hours and then changed to a medium containing 10%rat serum from spinal cord injury rat.After 24 hours of culture,the survival rate of each group of H9c2 cells was measured by CCK-8 assay.Western blot assay was used to detect the expression of autophagy related protein LC3 and p62 in H9c2 cells in each group. RESULTS AND CONCLUSION:Compared with the blank control group,there was no significant change in cell survival rate in the sham operated rat serum group(P>0.05).Compared with the sham operated rat serum group,the cell survival rate(P<0.01)and the expression of LC3 protein(P<0.05)in spinal cord injury rat serum group was significantly reduced,and the expression of p62 protein was significantly increased(P<0.05).Compared with the spinal cord injury rat serum group,the survival rate of cells in the luteolin pretreatment group significantly increased(P<0.000 1);the expression of LC3 protein significantly increased(P<0.05),and the expression of p62 protein significantly decreased(P<0.05).The results indicate that luteolin may improve myocardial cell death induced by serum from rats with spinal cord injury by promoting autophagy.

BACKGROUND:Parkinson's disease has the main pathological changes in the midbrain,especially in the dense substantia nigra,leading to impaired motor and non-motor function in patients.At present,research is limited by cellular heterogeneity,and its pathogenesis still needs to be further elucidated.In recent years,single-cell RNA sequencing(scRNA-seq)has gradually been applied in neurodegenerative diseases,which is of great significance for understanding intercellular heterogeneity,disease development mechanisms,and treatment strategies. OBJECTIVE:To review the research progress of scRNA-seq technology applied to Parkinson's disease in recent years,providing a theoretical basis for the application of scRNA-seq in the treatment and diagnosis of Parkinson's disease. METHODS:The first author used a computer system to search for relevant literature in the CNKI,WanFang,PubMed,and Web of Science databases,with the Chinese search terms"single-cell RNA sequencing,Parkinson's disease,cell heterogeneity,cell subtypes,dopaminergic neurons,glial cells"and English search terms"single-cell RNA seq,Parkinson disease,heterogenicity,subtypes,dopaminergic neurons,glial cells."71 articles were ultimately included for review and analysis. RESULTS AND CONCLUSION:(1)scRNA-seq is a high-throughput experimental technique that utilizes RNA sequencing at the single-cell level to quantify gene expression profiles in specific cell populations,revealing cellular mysteries at the molecular level.Compared with traditional sequencing techniques,scRNA-seq technology is used to reveal the diversity of cell types and changes in specific gene expression in complex tissues under various physiological and pathological conditions through automatic clustering analysis of cell transcriptome.(2)By using scRNA-seq,the development process of dopaminergic neurons and the unique functional characteristics of various cell subtypes are elucidated,in order to better understand potential therapeutic molecular targets.(3)The use of scRNA-seq analysis has improved our understanding of the response of Parkinson's disease glial cells,enabling us to comprehensively map and characterize different cell type populations,identify specific glial cell subpopulations related to neurodegeneration,and draw valuable single cell maps as reference data for future research.(4)The application of scRNA-seq to detect embryonic mice and stem cells will help improve the in vitro differentiation protocol and quality control of cell therapy,as well as evaluate the overall cell quality and developmental stage of dopaminergic neurons derived from stem cells.

BACKGROUND:Carnosic acid,a bioactive compound found in rosemary,has been shown to reduce inflammation and reactive oxygen species(ROS).However,its mechanism of action in osteoclast differentiation remains unclear. OBJECTIVE:To investigate the effects of carnosic acid on osteoclast activation,ROS production,and mitochondrial function. METHODS:Primary bone marrow-derived macrophages from mice were extracted and cultured in vitro.Different concentrations of carnosic acid(0,10,15,20,25 and 30 μmol/L)were tested for their effects on bone marrow-derived macrophage proliferation and toxicity using the cell counting kit-8 cell viability assay to determine a safe concentration.Bone marrow-derived macrophages were cultured in graded concentrations and induced by receptor activator of nuclear factor-κB ligand for osteoclast differentiation for 5-7 days.The effects of carnosic acid on osteoclast differentiation and function were then observed through tartrate-resistant acid phosphatase staining,F-actin staining,H2DCFDA probe and mitochondrial ROS,and Mito-Tracker fluorescence detection.Western blot and RT-PCR assays were subsequently conducted to examine the effects of carnosic acid on the upstream and downstream proteins of the receptor activator of nuclear factor-κB ligand-induced MAPK signaling pathway. RESULTS AND CONCLUSION:Tartrate-resistant acid phosphatase staining and F-actin staining showed that carnosic acid dose-dependently inhibited in vitro osteoclast differentiation and actin ring formation in the cell cytoskeleton,with the highest inhibitory effect observed in the high concentration group(30 μmol/L).Carnosic acid exhibited the most significant inhibitory effect during the early stages(days 1-3)of osteoclast differentiation compared to other intervention periods.Fluorescence imaging using the H2DCFDA probe,mitochondrial ROS,and Mito-Tracker demonstrated that carnosic acid inhibited cellular and mitochondrial ROS production while reducing mitochondrial membrane potential,thereby influencing mitochondrial function.The results of western blot and RT-PCR revealed that carnosic acid could suppress the expression of NFATc1,CTSK,MMP9,and C-fos proteins associated with osteoclast differentiation,and downregulate the expression of NFATc1,Atp6vod2,ACP5,CTSK,and C-fos genes related to osteoclast differentiation.Furthermore,carnosic acid enhanced the expression of antioxidant enzyme proteins and reduced the generation of ROS during the process of osteoclast differentiation.Overall,carnosic acid exerts its inhibitory effects on osteoclast differentiation by inhibiting the phosphorylation modification of the P38/ERK/JNK protein and activating the MAPK signaling pathway in bone marrow-derived macrophages.

BACKGROUND:Early exercise treatment is the main prevention way for traumatic joint contracture and is also a research focus.Swimming may be a potential intervention for joint contracture due to the special physical properties of water. OBJECTIVE:To explore the effects of swimming on the development of joint contracture in a rat model and study its mechanisms. METHODS:Twenty-four Sprague-Dawley rats were randomly divided into a blank control group(n=8)and a joint contracture group(n=16).After the surgical operation of knee joint contracture rat models,the joint contracture group was randomly subdivided into a surgical control group(n=8)and a swimming treatment group(n=8).Swimming started in the swimming treatment group in the second week after surgery and lasted for a total of 5 weeks.At the 6th week after surgery,the body mass,knee joint range of motion,and quadriceps diameter were tested,and the diameter/body mass index was calculated.Hematoxylin-eosin staining was performed to detect the pathological changes in the knee joint capsule and quadriceps muscle,and Masson staining was used to observe fibrotic changes in the knee joint capsule.Furthermore,the protein expression of transforming growth factor β1 and type I collagen in the knee joint capsule was quantified by immunohistochemical assay and western blot was performed to detect the protein expression of MuRF1 in the quadriceps femoris. RESULTS AND CONCLUSION:Compared with the blank control group,the knee range of motion decreased in the surgical control and swimming treatment groups(P<0.01),and knee extension deficit and arthrogenic extension deficit were significantly increased(P<0.01),the diameter of the quadriceps muscle was decreased(P<0.01),the joint capsule showed significant fibrosis,the quadriceps muscle was atrophied,and the diameter/body mass index was decreased(P<0.01).Compared with the surgical control group,the swimming treatment group showed a significant increase in knee joint range of motion and quadriceps diameter(P<0.01),and significant improvement in joint capsule fibrosis and quadriceps atrophy.Compared with the blank control group,collagen fiber content and expression of transforming growth factor β1 and type I collagen were increased in the joint capsule of rats in both the surgical control group and the swimming treatment group(P<0.01).Compared with the surgical control group,collagen fiber content and expression of transforming growth factor β1 and type I collagen protein in the joint capsule were decreased in the swimming treatment group.Compared with the blank control group,the expression of MuRF1 protein in the quadriceps muscle of rats in the surgical control group and the swimming treatment group was increased(P<0.05).Compared with the surgical control group,the expression of MuRF1 protein in the quadriceps muscle of rats in the swimming treatment group was decreased(P<0.05).To conclude,early swimming intervention reduces transforming growth factor β1 and type I collagen expression in the joint capsule of traumatic joint contracture rats,decreases MuRF1 expression in the quadriceps muscle,and increases joint range of motion and quadriceps diameter,thereby inhibiting the development of joint contracture.

BACKGROUND:Differentially expressed RNA-binding proteins in the intervertebral disc plays a key role in intervertebral disc degeneration,and decreased levels of the RNA-binding protein KRT18 are associated with degenerative disc disease,but its specific role in the nucleus pulposus cells has not yet been fully determined. OBJECTIVE:To investigate the interaction of KRT18 with mRNA and long non-coding RNA on nucleus pulposus cells of the intervertebral disc and its mechanism. METHODS:Normal and degenerated nucleus pulposus cells were obtained from nucleus pulposus samples of patients undergoing interbody fusion for lumbar fracture or intervertebral disc degeneration.iRIP-seq,functional enrichment analysis,and DNA microarray analysis were performed to identify the mRNA and long non-coding RNA binding with KRT18.Subsequently,KRT18 was knocked down in nucleus pulposus cells based on the analysis results,and the expression levels of related genes were detected at the protein and RNA levels through protein immunoblotting and qRT-PCR,respectively. RESULTS AND CONCLUSION:Through iRIP-seq analysis,we identified abundant KRT18 binding sites within the GUAAUC and AGCCUC sequences,indicating that KRT18 may be involved in regulating RNA transcription,translation,stability or play a role in cell signaling pathways.It can stably bind to mature mRNA,among which highly expressed genes include CRLF1,IGFBP4,etc.At the same time,the peak genes of long non-coding RNA binding with it include SNHG25,SNHG12,NEAT1,USP32,EIF4A2 and CDH4.Most of these genes are involved in various biological processes such as apoptosis and inflammation,and can mediate related pathways of extracellular matrix metabolism.KRT18 can regulate their stability,transport,translation,splicing and other functions,thus affecting gene expression and cell function.We further verified through experiments the knockdown of KRT18 in nucleus pulposus cells,and found that the level of extracellular matrix metabolism was inhibited and unbalanced,resulting in intervertebral disc degeneration in vitro.This study investigated the regulatory mechanism of KRT18 from the perspective of its binding with mRNA and long non-coding RNA for the first time,and speculated the potential function of KRT18 in the pathogenesis of intervertebral disc degeneration,laying a foundation for future research on the key functions of KRT18.

BACKGROUND:Deep muscle stimulation has the effects of releasing muscle adhesion,relieving muscle spasm,improving and restoring muscle compliance and elasticity.Electromyographic biofeedback therapy can promote nerve recovery and improve lower limb motor function and gait. OBJECTIVE:To observe the effect of the effect of deep muscle stimulation combined with electromyographic biofeedback therapy on the spasm of the triceps surae and gait changes after stroke by using a digital muscle detector and three-dimensional gait analysis system. METHODS:A total of 72 patients who met the inclusion criteria were selected from the Rehabilitation Department of the First Affiliated Hospital of Guangdong Pharmaceutical University from October 2020 to October 2023.And they were enrolled and randomly divided into two groups(n=36 per group):a control group and a combined group.The control group received routine rehabilitation therapies,electromyographic biofeedback and pseudo deep muscle stimulation,while the combined group received true deep muscle stimulation treatment on the basis of the control group,five times per week,for 4 consecutive weeks.The oscillation frequency and dynamic stiffness of the affected gastrocnemius muscle,active range of motion of the ankle dorsiflexion muscle,electromyographic signal of the tibialis anterior muscle,Fugl-Meyer assessment of the lower limbs,and three-dimensional gait analysis parameters were statistically analyzed before and after treatment in two groups. RESULTS AND CONCLUSION:After treatment,oscillation frequency and dynamic stiffness values of the inner and outer sides of the affected gastrocnemius muscle in both groups of patients were significantly reduced compared with before treatment(P<0.05),and the combined group showed a more significant decrease compared with the control group(P<0.05).The active range of motion of the ankle dorsiflexion muscle,electromyographic signal of the tibialis anterior muscle,and Fugl-Meyer scores after treatment were significantly increased or improved compared with before treatment(P<0.05),while the combined group showed a more significant increase or improvement compared with the control group(P<0.05).In terms of gait parameters,the walking speed,frequency,and stride in both groups of patients were significantly increased compared with before treatment(P<0.05),while the combined group showed a more significant increase compared with the control group(P<0.05).The percentage time of support phase on the healthy side was shortened compared with before treatment(P<0.05),while the combined group showed a more significant decrease compared with the control group(P<0.05).In addition,there was no significant difference between the two groups except for the percentage of healthy side support(P>0.05).To conclude,the combination of deep muscle stimulation and electromyographic biofeedback can effectively alleviate triceps spasm in the short term after stroke,improve ankle dorsiflexion function,enhance lower limb motor function,and improve gait.The treatment effect is significant and worthy of clinical promotion and application.

BACKGROUND:There is still no consensus on the optimal internal fixation for the treatment of Pauwels Ⅲ femoral neck fracture,and most of the related finite element analyses have been performed using a single simplified loading condition,and the biomechanical properties of commonly used internal fixation devices need to be further investigated. OBJECTIVE:To analyze the biomechanical characteristics of Pauwels Ⅲ femoral neck fractures treated with cannulated compression screw,dynamic hip screw,and femoral neck system by finite element method under different loading conditions of single-leg standing loads and sideways fall loads. METHODS:The DICOM data of healthy adult femur were obtained by CT scanning,imported into Mimics 15.0 software to obtain the rough model of bone tissue.The data exported from Mimics were optimized by Geomagics software,and then three internal fixation models were built and assembled with the femur model according to the parameters of the clinical application of the cannulated compression screw,dynamic hip screw,and femoral neck system by using Pro/E software.Finally,the three internal fixation models were imported into Ansys software for loading and calculation to analyze the stress distribution and displacement of the femur and the internal fixation under different working conditions of single-leg standing loads and sideways fall loads,as well as the stress characteristics of the calcar femorale and Ward's triangle. RESULTS AND CONCLUSION:(1)Under the single-leg standing load and the sideways fall load,the proximal femoral stress of the three internal fixation models was mainly distributed above the fracture end of the femoral neck.The peak stress of the proximal femoral end,fracture end,Ward triangle,and calcar femorale of the three internal fixation models were the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(2)Under the single-leg standing load and the sideways fall load,the peak displacement of the proximal femur of the three internal fixation models was all located at the top of the femoral head,and the peak displacement was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(3)The peak displacement of the three internal fixation models was all located at the top of the internal fixation device under the single-leg standing and sideways fall loading conditions,and the peak displacement values were the smallest in the femoral neck system internal fixation model and the largest in the cannulated compression screw internal fixation model.(4)The internal fixation stress of the three internal fixation models was mainly distributed in the area near the fracture end of the internal fixation device under the single-leg standing and sideways fall loads,and the peak value of internal fixation stress was the smallest in the femoral neck system model and the largest in the cannulated compression screw model.(5)These results suggest that the mechanical stability of the femoral neck system is the best,but there may be a risk of stress shielding of the fracture end and calcar femorale.The stress of the internal fixation device of the femoral neck system is more dispersed,and the risk of internal fixation break is lower.

BACKGROUND:Spinal canal decompression using uniportal endoscopic surgery is a new minimally invasive surgery in the treatment of lumbar spinal stenosis.However,this technique needs a steep learning curve and high requirements for surgical equipment and instruments,which limits its clinical application.We previously use the spinal endoscopy as a monitoring endoscopy and combined with unilateral biportal endoscopy to propose a hybrid technique of spinal endoscopy to achieve coaxial endoscopic operation and hands-separate operation. OBJECTIVE:To compare the clinical outcome of hybrid technique and uniportal endoscopic surgery in treatment of lumbar spinal stenosis with bilateral lower limb pain symptoms. METHODS:Ninety patients diagnosed of lumbar spinal stenosis with bilateral symptoms were included and retrospectively analyzed at First People's Hospital,Shanghai Jiao Tong University from August 2020 to August 2022.44 cases were included in group A(hybrid technique group),while 46 cases were included in group B(uniportal endoscopic surgery).The nerve decompression was observed during the surgery.Operation time,hospital stay time,and expenses were recorded in both groups.The visual analog scale scores of lower back pain and both lower extremities pain,Oswestry disability index scores of quality of life and excellent and good rate of modified Macnab criteria were recorded and compared at preoperative,postoperative 3 days,and postoperative 3 and 6 months. RESULTS AND CONCLUSION:(1)The operation time of group A was significantly shorter than that of group B(P<0.05).(2)The lower back pain and lower extremity pain of the severe side at postoperative 3 days,and 3 and 6 months were significantly relieved in both groups(P<0.05).The visual analog scale score of lower extremity pain on the mild side was significantly decreased at postoperative 3 days,3 and 6 months than preoperative score in the group A(P<0.05).The visual analog scale score of lower extremity pain on the mild side was significantly decreased at postoperative 3 days than preoperative score in the group B(P<0.05).The visual analog scale scores of lower extremity pain on the mild side at postoperative 3 and 6 months did not show significant difference than preoperative score in the group B.The comparison between the two groups showed that there was no significant difference in the visual analog scale scores of postoperative lower back pain and lower extremity pain of the severe side(P>0.05).The visual analog scale scores of lower extremity pain on the mild side in the group A were significantly lower than those of group B at postoperative 3 and 6 months(P<0.05).(3)The Oswestry disability index scores of both groups at postoperative 3 day were significantly lower than preoperative score(P<0.05),and there was no significant difference between the two groups 3 days after operation.Oswestry disability index scores of group A at postoperative 3 and 6 months were significantly decreased than preoperative score(P<0.05).The Oswestry disability index scores of group B at postoperative 3 and 6 months did not show significant differences than preoperative score(P>0.05).The comparison between the two groups showed the Oswestry disability index scores of group A were significantly lower than group B at postoperative 3 and 6 months(P<0.05).(4)The results of modified Macnab showed that the excellent and good rate of group A was significantly higher than that of group B(95%,78%,P<0.05).(5)It is indicated that the hybrid technique is a new spinal endoscopy technique,which has the advantages of less trauma and faster recovery as a minimally invasive surgery.The clinical outcome of hybrid technique is superior to that of uniportal endoscopic surgery in the treatment of lumbar spinal stenosis with bilateral symptoms.Additionally,it also has the advantages of good operational flexibility and high decompression efficiency as an open surgery.