Aim To observe the role of salvianolic acid B(Sal B)in enhancing the survival of random skin flaps and to preliminarily explore its potential mecha-nisms.Methods The appearance,degree of edema,color and hair condition of the skin flap were evaluated seven days after operation.The vascular network and blood flow of random flaps were measured by laser Doppler flow measurement.HE staining was used to detect the growth of microvessels in random flaps.The expressions of VEGF and CD34 were detected by im-munohistochemistry,the expressions of RIPK1,2 and LC3 Ⅱ were detected by immunofluorescence,and the effects of autophagy related proteins and signaling path-ways were detected by Western blot.Results The ex-perimental results showed that Sal B induced autophagy in the random skin flaps,promoted angiogenesis,and reduced oxidative stress and necrotic apoptosis,signifi-cantly increasing the survival rate of the flaps.Immu-nohistochemistry,immunofluorescence staining,and Western blot confirmed that Sal B induced autophagy in the random skin flaps by activating TFE3 protein.Conclusion Sal B can promote autophagy in cells of random skin flaps and reduce their necrotic apoptosis by activating TFE3 protein.

Objective:To explore the plasma metabolomic characteristics of children with transfusion-dependent thalassemia(TDT),and reveal the changes of metabolic pattern in children with TDT.Methods:23 children with TDT who received regular blood transfusion in Ganzhou Women and Children's Health Care Hospital in 2021 were selected,and 11 healthy children who underwent physical examination during the same period were selected as the control group.The routine indexes between children with TDT and the control group were compared,and then the metabolic composition of plasma samples from children with TDT and the control group was detected by liquid chromatography-mass spectrometry.An OPLS-DA model was established to perform differential analysis on the detected metabolites,and the differential metabolic pathways between the two groups were analyzed based on the differential metabolites.Results:The results of routine testing showed that the indexes of ferritin,bilirubin,total bile acid,glucose and triglycerides in children with TDT were significantly higher than those in healthy controls,while hemoglobin and total cholesterol were significantly lower(all P＜0.05).However there was no significant difference in lactate dehydrogenase between the two groups(P＞0.05).Compared with the control group,190 differential metabolites(VIP＞1)were identified in TDT children.Among them,168 compounds such as arginine,proline and glycocholic acid were significantly increased,while the other 22 compounds such as myristic acid,eleostearic acid,palmitic acid and linoleic acid were significantly decreased.The metabolic pathway analysis showed that the metabolic impact of TDT on children mainly focused on the upregulation of amino acid metabolism and downregulation of lipid metabolism.Conclusion:The amino acid and lipid metabolism in children with TDT were significantly changed compared with the healthy control group.This finding is helpful to optimize the treatment choice for children with TDT,and provides a new idea for clinical treatment.

Objective:To explore the application value of reticulocyte hemoglobin equivalent(Ret-He)for diagnosing latent iron deficiency in female plateletpheresis donors.Methods:A total of 230 female plateletpheresis donors in Fujian Blood Center from January to February 2022 were selected as the research group and divided into three groups:normal group,iron depletion(ID)group and iron deficient erythropoiesis(IDE)group,according to the severity of iron deficiency.The level of hemoglobin(HGB),mean corpuscular volume(MCV),mean corpuscular hemoglobin(MCH),coefficient of variation of red cell distribution width(RDW-CV)and Ret-He were measured by using the Sysmex XN automated hematology analyzer.Chemiluminescence immunoassay was used to detect iron biochemical indexes.Receiver operating characteristic(ROC)curve analysis was performed to evaluate the diagnosic value of relevant indicators in female blood donors with latent iron deficiency.Results:Ret-He in ID group was 32.55(31.15,33.10)pg,which was significantly lower than that in the normal group[33.80(32.73,34.70)pg](P＜0.05),and significantly higher than that in IDE group[30.40(28.70,31.50)pg](P＜0.05).ROC analysis in diagnosis of IDE demonstrated that the area under the curves(AUCs)of HGB,MCV,MCH,RDW-CV and Ret-He were 0.892,0.843,0.909,0.890,0.931,respectively.When the critical value of Ret-He was 32.05 pg,its sensitivity and specificity were 85.90％and 92.60％,respectively.However,all red blood cell parameters had poor diagnostic value for ID.Conclusion:Ret-He is a perfect predictor for latent iron deficiency in female blood donors.Detection of Ret-He can advance the diagnosis of iron deficiency in female blood donors to the IDE stage.

Objective To investigate the differences in visual perception between children with autism spectrum disorder(ASD)and typically developing(TD)children when watching different intention videos,and to explore the feasibility of machine learning algorithms in objectively distinguishing between ASD children and TD children.Methods A total of 58 children with ASD and 50 TD children were enrolled and were asked to watch the videos containing joint intention and non-joint intention,and the gaze duration and frequency in different areas of interest were used as original indicators to construct classifier-based models.The models were evaluated in terms of the indicators such as accuracy,sensitivity,and specificity.Results When using eight common classifiers,including support vector machine,linear discriminant analysis,decision tree,random forest,and K-nearest neighbors(with K values of 1,3,5,and 7),based on the original feature indicators,the highest classification accuracy achieved was 81.90% .A feature reconstruction approach with a decision tree classifier was used to further improve the accuracy of classification,and then the model showed the accuracy of 91.43% ,the specificity of 89.80% ,and the sensitivity of 92.86% ,with an area under the receiver operating characteristic curve of 0.909(P<0.001).Conclusions The machine learning model based on eye-tracking data can accurately distinguish ASD children from TD children,which provides a scientific basis for developing rapid and objective ASD screening tools.[Chinese Journal of Contemporary Pediatrics,2024,26(2):151-157]

Streptococcus anginosus group(SAG)used to be considered as normal oral flora.With the advance-ment of diagnostic techniques,an increasing number of case reports confirm that SAG group can be an opportunistic pathogen causing a series of fatal infection.Therefore,this article reviews the diseases caused by SAG as opportu-nistic pathogens and its related pathogenic mechanisms.

BACKGROUND:Pulsed electromagnetic fields,as an important physical therapy,are exactly effective in the treatment of osteoarthritis,but the mechanism has not been fully clarified. OBJECTIVE:To observe the effect of pulsed electromagnetic field on the degeneration of knee joint cartilage in aged rats. METHODS:Eight 6-month-old Sprague-Dawley rats were selected as the young group and were subjected to normal diet with no treatment.Sixteen 22-month-old Sprague-Dawley rats were randomly divided into old group(n=8)and pulsed electromagnetic field group(n=8).The rats in the pulsed electromagnetic field group were subjected to a pulsed electromagnetic field intervention,once a day,5 days per week for continuous 8 weeks.The rats in the old group were given no treatment.All rats were anesthetized and executed after 8 weeks for the detection of relevant indexes. RESULTS AND CONCLUSION:Compared with the young group,serum type Ⅱ collagen C-terminal peptide level was increased in the old group(P<0.05);compared with the old group,serum type Ⅱ collagen C-terminal peptide level was decreased in the pulsed electromagnetic field group(P<0.05).Micro-CT showed that the bone volume fraction,bone mineral density,and number of bone trabeculae decreased(P<0.05)and the trabecular separation increased(P<0.05)in the tibia of rats in the aged group compared with the young group;and the bone volume fraction,bone density,and number of trabeculae increased(P<0.05)and the trabecular separation decreased(P<0.05)in the tibia of rats in the pulsed electromagnetic field group compared with the aged group.The tibial plateau Safranin O-fast green staining showed that the articular cartilage structure of rats in the aged group was disorganized,and the number of chondrocytes was obviously reduced,and the tidal line could not be distinguished.The above results were improved in the pulsed electromagnetic field group.RT-qPCR and western blot assay showed that the mRNA and protein expression levels of matrix metalloproteinase 1,matrix metalloproteinase 13,P53 and P21 in the articular cartilage and subchondral bone of rats were elevated in the aged group compared with the young group(P<0.05)and decreased in the pulsed electromagnetic field group compared with the old group(P<0.05).To conclude,pulsed electromagnetic fields may improve osteoarthritis in aged rats by inhibiting chondrocyte senescence,alleviating articular cartilage degradation and inhibiting subchondral bone osteoporosis through suppressing the expression of P53/P21.

Atrial fibrillation(AF)is the most common arrhythmia in the world and is closely related to mortality of patients.So far,number of patients in China has approached 10 million.Identifying manageable risk factors for AF and developing appropriate prevention strategies possess critical significance in reducing occurrence of fatal AF and costs on healthcare system.Risk factors for AF include obesity,hypertension,diabetes,obstructive sleep apnea,etc.Alcohol consumption,smoking and a sedentary lifestyle have also been recognized as important factors in occur-rence and development of AF.The present article makes a review on role of modifiable risk factors of AF in occur-rence,development and treatment of AF and mechanisms of each potential risk factor associated with AF.

Ankylosing spondylitis (AS) combined with lower cervical fracture is often categorized into unstable fracture, with a high incidence of neurological injury and a high rate of disability and morbidity. As factors such as shoulder occlusion may affect the accuracy of X-ray imaging diagnosis, it is often easily misdiagnosed at the primary diagnosis. Non-operative treatment has complications such as bone nonunion and the possibility of secondary neurological damage, while the timing, access and choice of surgical treatment are still controversial. Currently, there are no clinical practice guidelines for the treatment of AS combined with lower cervical fracture with or without dislocation. To this end, the Spinal Trauma Group of Orthopedics Branch of Chinese Medical Doctor Association organized experts to formulate Clinical guidelines for the treatment of ankylosing spondylitis combined with lower cervical fracture in adults ( version 2024) in accordance with the principles of evidence-based medicine, scientificity and practicality, in which 11 recommendations were put forward in terms of the diagnosis, imaging evaluation, typing and treatment, etc, to provide guidance for the diagnosis and treatment of AS combined with lower cervical fracture.

Objective To explore the effect of propranolol on femoral fracture healing in mice through regulation of microRNA-92a-3p(miR-92a-3p)and its mechanism.Methods C57BL/6J male mice were randomly divided into sham group(equal amount of 0.9％NaCl),model group(equal amount of 0.9％NaCl),experimental group(50 mg·kg-1 propranolol administration),inhibitor group(mice were injected with 100 mg·kg-1 miR-92a-3p inhibitor via tail vein on the basis of the experimental group).Femur was severed and molded in all mice except sham operation group.X-ray was used to observe bone healing.Quantitative real time polymerase chain reaction was used to detect the expression of miR-92a-3p in femur tissues.The expression level of bone formation and bone metabolism markers was detected by enzyme linked immunosorbent assay.Western blot was used to detect the expression of pathway-related proteins.Results The X-ray scores of femur in sham group,model group and experimental group were 11.20±2.60,4.70±1.50 and 9.60±2.40,respectively;the relative expression levels of miR-92a-3p in sham operation group,model group,experimental group and inhibitor group were 1.00±0.09,0.73±0.06,0.90±0.07 and 0.78±0.06;alkaline phosphatase levels were(35.21±2.63),(43.16±3.29),(67.58±5.37)and(49.62±4.05)U·L-1,respectively;crosslaps levels were(4.57±0.52),(8.41±0.91),(4.26±0.67)and(5.73±0.84)ng·mL-1,respectively;the relative expression levels of brain derived neurotrophic factor were 1.00±0.14,0.58±0.05,0.83±0.09 and 0.71±0.06,respectively;the relative expression levels of phospho-tyrosine kinase receptor B were 1.00±0.12,0.62±0.05,0.89±0.08 and 0.76±0.07,respectively;the relative expression levels of phospho-extracellular regulated protein kinases were 1.00±0.11,0.54±0.04,0.78±0.07 and 0.65±0.05,respectively.The above indexes in the model group were compared with those in the sham group,those in the experimental group were compared with those in the model group,and those in the inhibitor group were compared with those in the experimental group,and the differences were statistically significant(P＜0.05,P＜0.001).Conclusion Propranolol can promote femoral fracture healing in mice,which may be achieved by up-regulating miR-92a-3p activation of brain derived neurotrophic factor/tyrosine kinase receptor B/extracellular regulated protein kinases signaling pathway.

Objective To analyze the magnetic resonance images (MRI) of patients with spinal epidural lipomatosis (SEL) in high-altitude areas and to determine the optimal cut-off value for diagnosis with epidural fat thickness. Methods This retrospective study included patients who underwent lumbosacral MRI examination for lumbosacral pain in Ping’an District Hospital of Traditional Chinese Medicine, Haidong City, China from January 1, 2021 to December 31, 2022. The epidural fat thickness in vertebral segments T12/L1 to L5/S1 was compared between the SEL group and the non-SEL group. The diagnostic efficacy with different cut-off values at each vertebral segment was evaluated. Between-group comparisons were performed using the t-test, Mann-Whitney U test, chi-square test, or modified chi-square test. The area under the receiver operating characteristic (AUC) was used to evaluate the diagnostic efficiency. The DeLong test was used to compare AUC between the two groups. Results A total of 370 patients were included (60 in the SEL group and 310 in the non-SEL group). There were no significant differences in age, sex, height, body weight, and body mass index between the two groups (all P > 0.05). At different vertebral segments, the epidural fat thickness was significantly higher in the SEL group than in the non-SEL group (all P < 0.05). The cut-off values for SEL diagnosis with epidural fat thickness in segments T12/L1 to L5/S1 were 2.23, 4.25, 4.85, 5.57, 7.21, and 8 mm, respectively. The AUC of MRI SEL diagnosis with epidural fat thickness in segment L5/S1 was the highest (0.945, 95% confidence interval [CI]: 0.916-0.966, P < 0.001). SEL diagnosis with epidural fat thickness > 8 mm in segment L5/S1 was the most accurate, with an AUC of 0.931 (95% CI: 0.901-0.955, P < 0.001), a sensitivity of 95.0%, and a specificity of 91.3%; this AUC was significantly higher than those of diagnosis with other cut-off values (all P < 0.05). Conclusion SEL patients have significantly increased epidural fat in the spinal canal. Epidural fat thickness > 8 mm in segment L5/S1 can be used for diagnosis of SEL with improved efficiency and accuracy.