BACKGROUND:Developmental dysplasia of the hip often leads to limb deformities in children,and the research related to its diagnosis and treatment has been gradually clarified.Recently,the finite element method has been paid attention to by scholars in the research related to developmental dysplasia of the hip because of its advantages. OBJECTIVE:Through literature search and review of the relevant research progress of finite element method in children's developmental dysplasia of the hip and treatment,analyze and summarize its advantages and disadvantages,and explore the direction of further research in the future. METHODS:PubMed,SCI,CBM,and CNKI were searched for relevant articles published from January 2014 to November 2023 with the key words of"developmental dysplasia(dislocation)of the hip,dysplasia of the hip,finite element analysis(method),pavlik harness,fixation in herringbone position,biomechanics,pelvic osteotomies,pemberton,salter,dega,periacetabular osteotomy,children"in Chinese and English.A small number of long-term articles were included,and 62 articles were finally included for analysis through screening. RESULTS AND CONCLUSION:(1)The mechanical environment of hip joint in children with developmental dysplasia of the hip was abnormal.The pressure in acetabulum was uneven.The stress increased and concentrated;the joint contact area decreased,and the local stress concentrated in femoral neck.(2)In the Pavlik sling and herringbone fixation,the mechanical environment of the hip was improved;the concentrated high stress area disappeared and the joint contact area increased,but the excessive abduction angle led to the increase of stress in the acetabulum and the lateral femoral head.(3)After pelvic osteotomy,the stress environment of hip joint and sacroiliac joint was improved.There was no single hinge in the three kinds of osteotomy,and the stress load position was different according to the age of the children.(4)After peri-acetabular osteotomy,the joint contact pressure was close to normal,but it was difficult to recover in patients with non-spherical femoral head.(5)The postoperative X-ray film findings could not show that the joint contact mechanics was the best.(6)It is indicated that the information that cannot be measured in the body can be obtained by using the finite element method,which can be operated in a virtual environment without the limitation of time and ethics.It can directly see the stress change area of normal and developmental dysplasia of the hip,explain the effectiveness of treatment from the point of view of mechanics,establish a specific finite element model and tailor-made operation plan for patients who need osteotomy.There is no standard or unified standard for the finite element modeling of developmental dysplasia of the hip and the material characteristic parameters of children's hip joint.Due to the inherent limitations of finite element method,it is impossible to analyze the model that contains bone,cartilage,ligament,muscle and other elements at the same time.The operation of finite element analysis is difficult,although it has advantages,it is not universal,and the current research sample size is small,which needs to be further expanded and verified.

Addressing the challenge of traditional physical/semi physical simulation methods being difficult to achieve full process and full element simulation of extravehicular activities,virtual reality technology is utilized to break through the limitations of physical environments and establish a virtual reality simulation system for extravehicular activities.Based on the application characteristics of space station extravehicular activity engineering,with the goal of improving system practicality and usability,integrating the visual immersion of virtual images,the ontology of real operation,and the consistency of virtual and real space perception,a three-dimensional scene simulation,multi-mode joystick interaction paradigm,continuous operation actions simulation of extravehicular operations,and interactive operation virtual/real space consistency method that were proposed and designed for the realistic visual perception and extravehicular operation.The system has been successfully applied to astronaut training,program validation,joint exercise,and flight control support for sixteen extravehicular activities from SZ-12 to SZ-18.The results showed that the complete reproduction of the static/dynamic realistic comprehensive scene was achieved on the ground for the human-machine operation in the entire process of extravehicular activity,and the system is an essential and important means of ground simulation for extravehicular activity.

Objective To discuss the application effect of using a stone extractor balloon catheter to assist in crossing the anastomotic stenosis in treatment of anastomotic biliary stenosis after liver transplantation using endoscopic retrograde cholangiopancreatography(ERCP).Methods Clinical data of 48 patients who developed anastomotic biliary stenosis after liver transplantation and underwent ERCP treatment were collected.Upon unsuccessful use of a dilation catheter to cross the stricture,attempts were made to cross the anastomotic biliary stenosis by using a stone extractor balloon catheter.The success rate of the procedure was recorded,intraoperative conditions were observed,treatment outcomes and complications were analyzed.Results The main presenting symptoms in the 48 patients on admission were abdominal discomfort(32 patients),fever(7 patients),pruritus(4 patients),jaundice(3 patients),and no obvious symptoms(2 patients).Preoperative magnetic resonance cholangiopancreatography(MRCP)examination revealed isolated stricture of the anastomotic site in 35 cases,and stricture associated with stones in 13 cases.Using the stone extractor balloon catheter as a guide,guidewire crossing of the anastomotic stenosis was successful in 26 cases,resulting in a success rate of 54.17%(26/48).Through statistical analysis of the successful group and the failed group,there was a significant difference in whether the distal biliary dilatation between the two groups,and the difference was statistically significant(χ2 = 8.39,P = 0.004).In the 26 successfully treated cases,alanine transaminase(ALT),aspartate transaminase(AST),γ-glutamyl transpeptidase(γ-GT),alkaline phosphatase(ALP),and total bilirubin(TBiL)levels decreased significantly 48 hours after the procedure(P<0.05),and no serious complications occurred.Conclusion The use of a stone extractor balloon catheter significantly increases the success rate of crossing anastomotic stenosis in the treatment of anastomotic biliary stenosis after liver transplantation,especially in cases with distal dilatation of the common bile duct.This approach is safe and worth promoting.

ObjectiveTo investigate the effect of total alkaloids of Corydalis saxicola on a rat model of lipopolysaccharide（LPS）-induced depression， as well as the pharmacokinetic characteristics of 8 of its major components. MethodTwenty-four male SD rats were randomly divided into normal group， model group， fluoxetine group（10 mg·kg^-1） and total alkaloids of C. saxicola group（210 mg·kg^-1）， with 6 rats in each group. In addition to the normal group， the rats were injected intraperitoneally with LPS to establish the inflammation model of depression， and the drug administration was started 1 week after modeling， and the administration groups were gavaged according to the corresponding dose， and the normal and model groups were intragastric administration with equal volume of distilled water， and the administration was performed along with the modeling. After two weeks of continuous administration， the effect of total alkaloids of C. saxicola on the behavior of depressed rats were tested by sucrose preference， forced swimming and open field experiments， the levels of tumor necrosis factor-α（TNF-α）， interleukin（IL）-1β and IL-6 in serum of rats were determined by enzyme-linked immunosorbent assay（ELISA）， the histopathological changes of rat hippocampus were observed by hematoxylin-eosin（HE） staining. After the last administration， blood was collected from orbit according to the set time， and ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry（UPLC-QqQ-MS） was established to simultaneously detect the concentrations of dehydrocavidine， tetrahydropalmatine， coptisine， palmatine， jatrorrhizine， berberine， berberrubine and epiberberine in plasma， and drug-time curves were drawn. The pharmacokinetic parameters were analyzed by DAS 2.0 software. ResultCompared with the normal group， the model group exhibited a decrease in sucrose preference rate， total distance traveled in the open field， as well as an increase in swimming immobility time and serum inflammatory factor expression（P<0.01）. In contrast， compared with the model group， rats in each administration group showed an increase in sucrose preference rate and total distance traveled in the open field， a decrease in swimming immobility time， and a reduction in serum inflammatory factor expression（P<0.05， P<0.01）. Additionally， HE staining results revealed that neurons in the hippocampus of rats from the model group were characterized by loss， disorganization and residual vacuoles， whereas those from the total alkaloids of C.saxicola group displayed an increase in number with orderly arrangement and clear cytoplasm. Pharmacokinetic results showed that the time to peak（t_max） and half-life（t_1/2） of the 8 active ingredients were 0.19-2.06 h and 3.71-8.70 h after continuous administration of total alkaloids of C. saxicola. Among them， the area under the curve（AUC_0-∞） of tetrahydropalmatine was the highest and the t_1/2 was the shortest， and the AUC_0-∞ of coptisine， palmatine， jatrorrhizine， berberine， berberrubine and epiberberine were low. The curves of dehydrocavidine， coptisine， palmatine， berberine and epiberberine showed obvious double peak phenomenon. ConclusionTotal alkaloids of C. saxicola can improve the depression-like behavior of rats， inhibit the expression of inflammatory factors in serum， improve the pathological injury of hippocampus， and has the antidepressant effect. Meanwhile， the effective site is absorbed quickly and eliminated slowly in the depressed model rats， and the efficacy is maintained for a long time.

BACKGROUND:Currently,the verification of the precision of personalized bone models is usually performed by methods such as paired t-tests or intraclass correlation coefficient,but such methods often require the production of large batches of models,which do not satisfy the need for immediate use of personalized models. OBJECTIVE:To study the feasibility of establishing the equivalent model to verify the precision of the personalized bone model rapidly. METHODS:Bone CT images of three adults were randomly obtained for reconstruction.3D printing was used to create personalized bone models,and then the personalized bone models were scanned using CT and reconstructed.Mimics was used to compare the reconstructed models of bone CT images with the bone CT images.Geomagic Studio was used to analyze the fitting deviation between the reconstruction model of personalized bone model CT image and the reconstruction model of skeletal CT image.The 3D-printed personalized bone model was measured against the measurement positions and dimensions marked on the reconstruction model of skeletal CT image,and the error was calculated. RESULTS AND CONCLUSION:(1)By comparing the reconstructed bone CT image model with the bone CT scan image,the two were compatible in terms of anatomical structure and morphology,and the contours almost overlapped.(2)By fitting bias analysis,the standard bias was 0.176,0.226,and 0.143 mm in order,and all the results were<0.25 mm.(3)By measuring and calculating the model,the mean relative errors were 0.44%,0.21%,and 0.13%,and all the results were within 5%error.(4)The constructed equivalent model was in line with the basic conditions for making personalized bone models.The established equivalent model met the clinical needs and design requirements,and it was feasible to use the method of the equivalent model to verify the precision of the personalized bone model quickly.(5)This method could provide a targeted and rapid way to verify the precision of personalized bone models.It could achieve the goal of providing immediate clinical use without the need to produce large batches of models compared to conventional methods such as paired t-tests or intraclass correlation coefficient.

Objective To observe the changes in the symptoms and relevant physiological indicators in subjects after inhaling the hypoxic air produced by a hypoxic air generator at a low altitude prior to their entry into high-altitude environment,and to explore its early warning effect for acute mountain sickness(AMS)among the subjects upon their subsequent entry into high-altitude environment.Methods A total of 50 subjects who were going to visit high-altitude regions were enrolled.All subjects were men,with an average age of(22.00±1.52)years.They continuously inhaled for 30 minutes hypoxic air(which simulated the air at the altitude of 5200 m,with an oxygen content 10.80％)generated by a hypoxic air generator.During this period fingertip oxygen saturation,heart rate,blood pressure,and symptoms of discomfort were observed and recorded.On the fourth day after living at an altitude of 4020 m,the subjects completed the evaluation for the symptom scores of acute mild altitude disease(AMAD).The subjects were divided into a maladjusted group(18 cases)and a well-adjusted group(32 cases)according to whether they experienced discomfort(including drowsiness,dizziness,chest tightness,cold sweating of the hands,etc.)during the inhalation of hypoxic air at a low altitude.After entry into the high-altitude environment,they were divided into an AMS group(28 cases)and a non-AMS group(22 cases)according to whether they experienced AMS after entering the he high-altitude environment.The primary indicator was the incidence of AMS,including the incidence of AMAD and severe acute mountain sickness(SAMS),and the incidence of AMS in the maladjusted group and the well-adjusted group after entering high-altitude environment.The secondary indicator was the relationship between the changes in fingertip oxygen saturation after inhaling hypoxic air at a low altitude and the incidence of AMS and the AMAD symptom scores.Results All 50 subjects traveled by air to the target altitude of 4020 m above sea level at the same time.The AMS incidence among them was 56.0％(28/50),with the incidence of AMAD being 54.0％(27/50)and the incidence of SAMS being 2.0％(1/50).In the single case of SAMS,the patient had high-altitude pulmonary edema.The incidences of AMS after entering high-altitude environment in the maladjusted and well-adjusted groups were 88.9％(16/18)and 37.5％(12/32),respectively,and the difference was statistically significant(P＜0.01).In the 50 subjects,fingertip oxygen saturation decreased rapidly in the first 11 minutes into the inhalation of hypoxic air at a low altitude,with a more pronounced decrease in the AMS group than that in the non-AMS group,and the differences between the groups were statistically significant after 5,9,and 11 minutes(P＜0.05).Fingertip oxygen saturation plateaued in the 50 subjects from the 12th to the 30th minute,with no significant differences between the AMS and non-AMS groups.The mean value of fingertip oxygen saturation within 30 minutes of hypoxic air inhalation was negatively correlated with the AMAD symptom scores after subjects'entry into high-altitude environment(r=-0.300).Conclusion Those who experience symptoms of discomfort after exposure to hypoxic air produced by a hypoxic air generator at a low altitude are more likely to develop AMS and close attention should be paid to the decrease in fingertip oxygen saturation within the first 11 minutes.

Objective: Based on physical activity (PA) and sedentary behavior (SB) variables on weekdays and weekends, the study aims to cluster the physical activities inside and outside kindergartens and to explore the cluster characteristics of different children using physical fitness indicators, so as to provide new strategies and methods for early childhood education and health. Methods: From March to June 2019, 291 children aged 3-6 years from 6 kindergartens in Nanchang were recruited by a stratified cluster random sampling method. The ActiGraph GT3X-BT triaxial accelerometer was used to measure and analyze the PA and SB levels inside and outside the kindergarten. A twostep clustering algorithm model was employed for cluster analysis. Physical fitness were measured and evaluated according to the "National Physical Fitness Measurement Standard Manual (Preschool Section)". Differences in physical fitness among different clusters of children were compared, and the cluster characteristics of different children were analyzed. Results: The clustering algorithm model indicated that based on six indicators, including PA and SB inside the kindergarten on weekdays, and PA and SB outside the kindergarten on both weekdays and weekends, children could be divided into three categories:active inside (high PA, low SB inside), active outside (high PA outside), and inactive (low PA, high SB both inside and outside). The average silhouette coefficient of the model was 0.3, indicating good clustering results. Both the active inside and active outside children showed significantly higher PA inside on weekdays, PA outside on weekdays and weekends, daily low intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) than the inactive children ( F=157.91, 80.79 , 95.86, 95.52, 124.74, P <0.05). After adjusting for gender and age, the physical fitness scores of both active outside ( 19.03 ±0.47) and active inside (19.11±0.40) were significantly higher than those of the inactive children (17.94±0.31). Additionally, active inside children (3.91±0.14) also showed significantly better performance in continuous double-leg jumps, compared to inactive children (3.45±0.11) ( P <0.05). Conclusion Children active inside and those active outside perform well in PA. Future research should focus on the proportion of structured and unstructured PA time to enhance the overall physical fitness of children.

Objective To investigate the effects of N-acetyl-D-glucosamine(GlcNAc)on acute pancreatitis in rats.Methods Twenty male SD rats were randomly divided into a control group,AP group,low GlcNAc + AP group and high GlcNAc + AP group,with five rats in each group.Acute pancreatitis was induced in AP group,low GlcNAc + AP group and high GlcNAc + AP group by two intraperitoneal injections of 2.5 g/kg L-arginine with a 1 hour interval.Among them,low GlcNAc + AP group and high GlcNAc + AP group were administered 50 and 200 mg/kg GlcNAc,respectively,by intraperitoneal injection at 24 hours before the first intraperitoneal injection of L-arginine.Group control and AP were intraperitoneally injected with the same volume of normal saline.After 24 h,the rats were sacrificed,and serum and pancreatic tissues were collected.Pancreatic tissue morphology was observed by HE staining,and serum levels of amylase(AMY),lipase(LPS),interleukin-1β(IL-1β),interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),superoxide dismutase(SOD)and malondialdehyde(MDA)were measured by enzyme-linked immunosorbent assay.Protein expression of nuclear factor E2-related factor 2(NRF2),heme oxygenase-1(HO-1),and peroxisome proliferator-activated receptor-γ(PPAR-γ)in pancreatic tissue was detected by Western Blot.Cluster of differentiation(CD)86,CD206 and macrophage markers(F4/80)were detected by immunofluorescence.Expression of CD86 and CD206 in pancreatic tissue was detected by immunohistochemistry.Results(1)Compared with control group,AMY,LPS,IL-1β,IL-6,TNF-α,and MDA levels and pancreatic CD86 expression in AP group were significantly increased(P<0.05),while SOD activity,protein expression levels of NRF2,HO-1,and PPAR-γ,and pancreatic CD206 expression were significantly decreased(P<0.05).(2)Compared with AP group,serum IL-1β,IL-6,TNF-α,MDA,and LPS and the pancreatic CD86 expression in low GlcNAc + AP group were significantly decreased(P<0.05).The PPAR-γ protein level in the pancreas was significantly increased(P<0.05).(3)Compared with AP group,serum AMY,LPS,IL-1β,IL-6,TNF-α,and MDA and pancreatic CD86 expression in high GlcNAc + AP group were significantly decreased(P<0.05),while serum SOD,and NRF2,HO-1,PPAR-γ,and pancreatic CD206 expression were significantly increased(P<0.05).(4)Compared with low GlcNAc + AP group,serum LPS,IL-1β and IL-6 in high GlcNAc + AP group were significantly decreased(P<0.05).Pancreatic expression of HO-1,PPAR-γ,and pancreatic CD206 were significantly increased(P<0.05).Conclusion GlcNAc treatment attenuates acute pancreatitis injury in AP rats,possibly by activating the NRF2/HO-1 signaling pathway to inhibit oxidative stress and promoting M2 macrophage polarization to attenuate pancreatic injury in AP rats.

Objective:To understand the epidemiological and clinical characteristics of human infection with avian influenza A(H3N8) virus and the molecular biological characteristics of the pathogen, and provide scientific evidence for the prevention and control of human infection with avian influenza A(H3N8) virus.Methods:An epidemiological investigation was conducted for a case of human infection with avian influenza A(H3N8) virus in Changsha in May 2022 to collect the information about exposure history, route of infection, onset and treatment, potential contacts and other possible exposures for a descriptive analysis. Nucleic acid detection and gene sequencing were used to detect the pathogen and analyze the genetic characteristics.Results:The case had a history of exposure to live poultry trading market 6 days before the onset of illness. Subtypes H3 and N8 of avian influenza virus were detected in live poultry markets. Deep gene sequencing showed that the virus had adaptive mutations in mammals, reduced sensitivity to alkamine agent, and no resistance mutations related to neuraminidase inhibitors and polymerase inhibitors were detected.Conclusion:The case was infected due to exposure to the live poultry market environment contaminated by avian influenza A(H3N8) virus, and no human to human transmission was found.

Objective:To establish a lectin enzyme-linked immunosorbent assay (lectin-ELISA) for the dection of sialylated fetuin-A and to explore the clinical diagnostic value of sialylated fetuin-A in hepatocellular carcinoma (HCC).Methods:From January 2017 to December 2020, 300 HCC patients and 160 disease controls, including 36 liver cirrhosis subgroups and 124 chronic hepatitis B subgroups, were collected from Shanghai Eastern Hepatobiliary Surgery Hospital. At the same time, 100 healthy subjects were collected as healthy controls. Lectin-ELISA method for detecting sialylated fetuin A was established based on the principle that Sambucus nigra lectin (SNA) can recognize the structure of α-2, 6-linked sialic acid residues. Differences between groups were compared using t-test or analysis of variance. Logistic regression method was used to establish the multi-index joint detection model, and receiver operating characteristic curve (ROC) was used to evaluate the efficacy of single index and joint detection model in the diagnosis of HCC.Results:A lectin-ELISA method for the detection of serum Sia-fetuin A was established. The linear regression coefficient of the system was 0.978 5, and the precision evaluation and interference experiments were in line with the clinical detection requirements. Using this method to detect serum Sia-fetuin A levels in each group, the levels of HCC group, disease control group and healthy control group were 1.362±0.310, 1.199±0.370, 1.086±0.420, respectively, and the three groups decreased in turn. The areas under the curve of Sia-fetuin A, α-fetoprotein, and their combined detection models for differential diagnosis of HCC were 0.790, 0.809, and 0.860, respectively. The diagnostic model had a sensitivity of 79.3% (238/300) and a specificity of 95.0% (247/260). Among the 300 patients in the HCC group, 138 (46%) patients were negative for serum AFP (<20 μg/L), and their serum Sia-fetuin A level was 1.364±0.305. Combining the disease control group and the healthy control group into the non-Cancer group, the serum Sia-fetuin A level was 1.146±0.381. The serum level of Sia-fetuin A in AFP-negative HCC patients was higher than that in non-HCC group ( t=6.134, P<0.001). The areas under the curve of Sia-fetuin A and the combined diagnostic model for the diagnosis of AFP-negative HCC were 0.776 and 0.919, respectively. The combined diagnostic model had a sensitivity of 93.4% (129/138) and a specificity of 77.3% (201/260). Conclusion:Serum Sia-fetuin A and combined determination model can provide a new auxiliary diagnostic index for AFP-negative HCC.