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.

Objective:To explore the value and related mechanism of preoperative serum sialic acid (SA) on evaluating microvascular invasion (MVI) in patients with intrahepatic cholangiocarcinoma (ICC).Methods:A total of 91 patients who underwent surgical resection and were pathologically diagnosed with ICC from December 2020 to September 2024 at the Oriental Hepatobiliary Surgery Hospital affiliated to the Naval Medical University were included in this retrospective analysis. The patients were divided into non-MVI (41 cases) and MVI groups (50 cases). The general data and laboratory examination indexes were collected and analyzed. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for predicting MVI. The predictive value of serum indicators for MVI was evaluated by receiver operating characteristic curves. The correlation between MVI and SA was analyzed by point-biserial correlation. ICC cells stably overexpressing β-galactoside α2, 6-sialyltransferase 1 (ST6GAL1) were generated through lentiviral transfection. ST6GAL1 protein expression and mRNA expression were detected by Western blot and quantitative real-time polymerase chain reaction, respectively. Sambucus nigra (SNA) lectin fluorescence staining was used to detect α2, 6-sialylation levels on cells. Cell migration ability was assessed by wound healing and Transwell assays, and cell proliferation was evaluated by colony formation assays.Results:Compared with the non-MVI group, patients in the MVI group exhibited significantly higher levels of fibrinogen, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase, SA and 5′-nucleotidase (5′-NT) (all P<0.05). Multivariate logistic regression analysis revealed that SA ( OR=1.01,95% CI 1.01-1.02, P=0.023) was the only independent predictor for MVI. The area under curve of SA in predicting MVI was 0.757 (95% CI 0.640-0.870), sensitivity 67.65%, specificity 77.78%. SA was positively correlated with MVI ( r=0.443, P<0.001). ICC cells overexpressing ST6GAL1 were featured with increased mean fluorescence intensity of SNA lectin, and increased level of α2, 6-sialylation on the cell surface (both P<0.05). The number of colonies formed by hypersialylated ICC cells was also increased ( P<0.05), and both the migration rate and the number of migrating cells were significantly higher ( P<0.05). Conclusions:Serum SA is an independent predictor for MVI in ICC patients. Hypersialylation in ICC cells is associated with higher malignancy.

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 explore the value and related mechanism of preoperative serum sialic acid (SA) on evaluating microvascular invasion (MVI) in patients with intrahepatic cholangiocarcinoma (ICC).Methods:A total of 91 patients who underwent surgical resection and were pathologically diagnosed with ICC from December 2020 to September 2024 at the Oriental Hepatobiliary Surgery Hospital affiliated to the Naval Medical University were included in this retrospective analysis. The patients were divided into non-MVI (41 cases) and MVI groups (50 cases). The general data and laboratory examination indexes were collected and analyzed. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for predicting MVI. The predictive value of serum indicators for MVI was evaluated by receiver operating characteristic curves. The correlation between MVI and SA was analyzed by point-biserial correlation. ICC cells stably overexpressing β-galactoside α2, 6-sialyltransferase 1 (ST6GAL1) were generated through lentiviral transfection. ST6GAL1 protein expression and mRNA expression were detected by Western blot and quantitative real-time polymerase chain reaction, respectively. Sambucus nigra (SNA) lectin fluorescence staining was used to detect α2, 6-sialylation levels on cells. Cell migration ability was assessed by wound healing and Transwell assays, and cell proliferation was evaluated by colony formation assays.Results:Compared with the non-MVI group, patients in the MVI group exhibited significantly higher levels of fibrinogen, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase, SA and 5′-nucleotidase (5′-NT) (all P<0.05). Multivariate logistic regression analysis revealed that SA ( OR=1.01,95% CI 1.01-1.02, P=0.023) was the only independent predictor for MVI. The area under curve of SA in predicting MVI was 0.757 (95% CI 0.640-0.870), sensitivity 67.65%, specificity 77.78%. SA was positively correlated with MVI ( r=0.443, P<0.001). ICC cells overexpressing ST6GAL1 were featured with increased mean fluorescence intensity of SNA lectin, and increased level of α2, 6-sialylation on the cell surface (both P<0.05). The number of colonies formed by hypersialylated ICC cells was also increased ( P<0.05), and both the migration rate and the number of migrating cells were significantly higher ( P<0.05). Conclusions:Serum SA is an independent predictor for MVI in ICC patients. Hypersialylation in ICC cells is associated with higher malignancy.

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.

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.

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.

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 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.