OBJECTIVE: To investigate the impact of bone mass and volume of low-density zones beneath the tibial plateau on the maximum von Mises stresses experienced by the cartilage and meniscus in the knee joint. METHODS: The study included one healthy adult volunteer, from whom CT scans were obtained, and one patient diagnosed with knee osteoarthrisis (KOA), for whom X-ray films were acquired. A static model of the knee joint featuring a low-density zone was established based on a normal knee model. In the finite element analysis, axial loads of 1 000 N and 1 800 N were applied to the weight-bearing region of the upper surface of the femoral head for model validation and subsequent finite element studies, respectively. The maximum von Mises stresses in the femoral cartilage, as well as the medial and lateral tibial cartilage and menisci, were observed, and the stress percentage of the medial and lateral components were concurrently analyzed. Additionally, HE staining, as well as alkaline magenta staining, were performed on the pathological specimens of patients with KOA in various low-density regions. RESULTS: The results of model validation indicated that the model was consistent with normal anatomical structures and correlated with previous calculations documented in the literature. Static analysis revealed that the maximum von Mises stress in the medial component of the normal knee was the lowest and increased with the advancement of the hypointensity zone. In contrast, the lateral component exhibited an opposing trend, with the maximum von Mises stress in the lateral component being the highest and decreasing as the hypointensity zone progressed. Additionally, the medial component experienced an increasing proportion of stress within the overall knee joint. HE staining demonstrated that the chondrocyte layer progressively deteriorated and may even disappear as the hypointensity zone expanded. Furthermore, alkaline magenta staining indicated that the severity of microfractures in the trabecular bone increased concurrently with the expansion of the hypointensity zone. CONCLUSION The presence of subtalar plateau low-density zone may aggravate joint degeneration. In clinical practice, it is necessary to pay attention to the changes in the subtalar plateau low-density zone and actively take effective measures to strengthen the bone status of the subtalar plateau low-density zone and restore the complete biomechanical function of the knee joint, in order to slow down or reverse the progression of osteoarthritis.
Humans ; Finite Element Analysis ; Knee Joint/physiology* ; Tibia/anatomy & histology* ; Cartilage, Articular/physiology* ; Menisci, Tibial/physiopathology* ; Tomography, X-Ray Computed ; Osteoarthritis, Knee/diagnostic imaging* ; Weight-Bearing ; Bone Density ; Adult ; Stress, Mechanical ; Male ; Middle Aged ; Biomechanical Phenomena ; Female

Astragalus membranaceus possesses the function of enhancing immunity, protecting the liver, diuretic, anti-aging, anti-stress, anti-hypertensive, and more extensive antibacterial effects. Polysaccharides, one kind of the major active ingredients of A. membranaceus, are considered to be responsible for their versatile use. Now, a systematic summary of research progress and prospects of polysaccharides from A. membranaceus polysaccharides (AMPs) is necessary to facilitate their further study and application. In this review, the optimal extraction methods, structural features, biological activities, and applications of AMPs were emphasized. The structure-activity relationships are also analyzed and elucidated. Solvent, ultrasonic, microwave, enzyme-assisted, ultra-high pressure, and combined methods have been used to extract AMPs. Among them, solvent extraction is the most commonly used method because it is simple and easy to operate, but the efficiency needs to be improved further. The ultra-high pressure method is the most efficient but has a low economic return. AMPs exhibited various bioactivities, including immunomodulation, antitumor, and antidiabete. The structure-activity relationships revealed that different structure configurations, chain conformations, and physical properties would have different bioactivities. However, the new method for purification of certain polysaccharides, detailed structure-activity relationships (SAR), mechanisms of bioactivities, and quality control of AMPs need to be extensively investigated.

OBJECTIVE: Pseudostellaria heterophylla has been paid more attention in recent years, mainly as a medicine food homology plant. The content determination of P. heterophylla is not specified in the Chinese Pharmacopoeia (version 2020). The environmental conditions in different production areas could exert an influence on the quality of P. heterophylla. The purpose of this study is to discriminate P. heterophylla collected from different geographical origins of China. METHODS: In this study, the content of polysaccharide in 28 batches of P. heterophylla was determined using phenol-sulfuric acid. HPLC fingerprints were established under optimised HPLC-PDA methods. Subsequently, the similarity analysis (SA) and the quantification of heterophyllin B were analyzed. The metabolites of P. heterophylla were identified and evaluated using UHPLC-Q Exactive HF orbitrap MS system. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), hierarchical cluster analysis (HCA) and orthogonal PLS-DA (OPLS-DA) were performed based on all peak areas. RESULTS: The polysaccharide content in Guizhou and Jiangsu was higher than that of other production areas, which varied significant from different origins. While the content of heterophyllin B in Anhui and Jiangsu was high. The correlation coefficients of HPLC fingerprints for 28 batches samples ranged from 0.877 to 0.990, and the characteristic map can be used to identify and evaluate the quality of P. heterophylla. The samples from Fujian, Guizhou, Jiangsu provinces can be relatively separated using multivariate statistical analysis including PCA, PLS-DA, HCA, OPLS-DA, indicating that their metabolic compositions were significantly different. Ultimately, a total of 15 metabolites which were filtrated by a VIP-value > 1 and a P-value < 0.05 associated with the separation of different origins were identified. CONCLUSION HPLC fingerprint was established to evaluate the quality and authenticity of P. heterophylla. The present work showed that the difference of geographic distributions had an influence on the internal chemical compositions. A sensitive and rapid untargeted metabolomics approach by UHPLC-Q Exactive HF orbitrap MS was utilized to evaluate P. heterophylla from different origins in China for the first time. Overall, this study provides insights to metabolomics of P. heterophylla and supplies important reference values for the development of functional foods.

ObjectiveTo investigate the identification of kidney Yang deficiency syndrome of patients with osteoporosis（OP）， and to form the clinical syndrome identification rules of traditional Chinese medicine（TCM）. MethodBasic information， etiology， clinical symptoms and other characteristics of 982 OP patients were included， and statistical tests were used to screen the variables associated with kidney Yang deficiency syndrome. Taking the decision tree as the base model， bootstrap aggregation algorithm（Bagging algorithm） was utilized to establish the classification model of kidney Yang deficiency syndrome in OP， generating numerous rules and removing redundancy. Combining least absolute shrinkage and selection operator（LASSO） regression to screen key rules and integrate them to construct an identification model， achieving the identification of kidney Yang deficiency syndrome in OP patients. ResultEighteen key identification rules were screened out， and of these， where 11 rules with regression coefficients>0 correlated positively with the kidney Yang deficiency syndrome， the rule with the highest coefficient was chilliness（present）&feverish sensation over the palm and sole（absent）. The other 7 rules with regression coefficients<0 correlated negatively with the syndrome， the rule with the lowest coefficient was reddish tongue（present）&diarrhea（absent）&deficiency of endowment（absent）. According to the regression coefficients of each key rule， variables with importance>0.2 were ranked as chilliness， reddish tongue， feverish sensation over the palm and sole， cold limbs， clear urine， diarrhea， deficiency of endowment， prolonged illness. The results of the partial dependence analysis of the identification model showed that compared to OP patients without chilliness， those with chilliness（present） had a 0.266 8 higher probability of being identified as having kidney Yang deficiency syndrome， indicating that this variable had the highest impact on identification of the syndrome. Similarly， compared to OP patients without reddish tongue， those with reddish tongue had a 0.141 9 lower probability of being identified as having kidney Yang deficiency syndrome， indicating that this variable had the highest impact on identifying non-kidney Yang deficiency syndrome. The accuracy， sensitivity， specificity and area under receiver operating characteristic curve（AUC） of the established kidney Yang deficiency syndrome identification model in the test set were 0.865 9， 0.853 7， 0.872 0 and 0.931 5， respectively. ConclusionA precise identification model of OP kidney Yang deficiency syndrome is conducted basing on the rule ensemble method of Bagging combining LASSO regression， and the screened key rules can explain the identification process of kidney Yang deficiency syndrome. In this research， according to the regression coefficients of rules， the importance and partial dependence of variables， combined with the thinking of TCM， the influence of patient characteristics on the identification of syndromes is described， so as to reveal the primary and secondary syndromes of identification and assist the clinical identification of kidney Yang deficiency syndrome.

Objective:To evaluate the effectiveness of staged modular theory and practice lectures in laparoscopic training.Methods:In this study, a large group of medical students and a large group of residents were selected, and each of the two groups was divided into an experimental group and a control group respectively. The experimental group received staged modular theory and practice lectures based on the conventional trainings, and the control group only underwent conventional laparoscopic skills training and instruction. Before and after the training, the completion time of 6 basic laparoscopic operations, laparoscopic suture time, suture quality and the number of accidental injuries were recorded and scored in each group according to the assessment criteria. SPSS 26.0 was used for statistical analysis of the assessment data. Independent samples t-test or Mann-Whitney U test was used for inter-group comparison between the two large groups, and paired samples t-test or Wilcoxon sign rank sum test was used for intra-group comparison before and after the training. Results:Compared with the control group, the experimental group of medical students that had undergone staged modular theory and practice lectures had a shorter time to complete basic laparoscopic operations, faster speed of suturing ( t=6.18, P<0.001) and higher quality of suturing ( t=4.17, P<0.001) and fewer accidental injuries ( Z=-2.03, P=0.043); the experimental group of residents that had undergone staged modular theoretical and practical lectures had a shorter time to complete basic laparoscopic operations, faster speed of suturing ( t=3.31, P=0.002) and higher quality of suturing ( t=3.68, P=0.001) and fewer accidental injuries ( Z=-2.44, P=0.015). Conclusion:The staged modular theory and practice lectures are able to further improve the quality of basic laparoscopic skills training.

Objective:To explore a new technology that can protect the lungs and heart better by utilizing the dose distribution attributes of the half-field and the characteristics of the VMAT (volumetric modulated arc therapy) technology.Methods:A three-dimensional water tank was used to measure the dose of symmetrical field and half field edge and analyze them comparatively. A total of 50 patients with left breast cancer receiving the postoperative radiotherapy were selected. Among them, 25 patients were performed conserving surgery and 25 patients were performed radical mastectomy. After the operation, all the patients received the prescription dose of 50 Gy in 25 fractions. Based on the Eclipse system, the symmetrical field continuous arc VMAT technology and the semi-field segmented arc VMAT technology were used to design the plan. Besides, the dose suitability data and the treatment efficiency of target areas and organs at risk were compared and analyzed.Results:The radiation size of half-field did not increase with the increased depth in the water mode. The symmetric field gradually enlarged due to the angle of tensor factor, increased to about 2 cm at the depth of 30 cm, and the delivery dose in the half-field was lower than that in the symmetric field. The closer the field edge is, the more obvious it is. Compared with the symmetric field continuous arc plan, the half-field segmental arc VMAT plan significantly improved the delivery dose of the lungs and heart ( t=-4.11, -4.42, P=0.00), in which the mean values of V5, V30, and Dmean for the whole structure of the heart were reduced by 52.5%, 65.5%, and 47%, respectively. The left anterior descending coronary artery, which was closely related to the target area, had a decrease of more than 20%. The mean values of V5, V10, V20, and Dmean of the affected lung were reduced by 21.6%, 24.8%, 25.0%, and 23.2%, respectively. The mean values of the doses of other endangered healthy organs, and the execution time of half-field segment arc plan were also better than the continuous arc plan. Conclusions:For breast cancer radiotherapy, the combination of half-field and VMAT can give full play to the advantages of half-field and VMAT, and significantly reduce the irradiated dose of the heart, affected lung, and healthy side of the breast.

Objective:To evaluate the effect of TBK1 overexpression on hypoxia-reoxygenation (H/R) injury in isolated mouse cardiomyocytes subjected to high glucose and the relationship with mitochondrial autophagy.Methods:Normally cultured log-phase HL-1 mouse cardiomyocytes were inoculated in a 6-well plate at a density of 1×10 6 cells/ml and were divided into 4 groups ( n=10 each) using a random number table method: control group (group C), high glucose group (group HG), high glucose and H/R group (group HG+ H/R), and TBK1 overexpression group (group TBK1). The cells were incubated in culture medium with 1% fetal bovine serum and 1% double antibody for 24 h when the cell density reached 50%.When the cell density reached 80%, pcDNA3.1 (+ ) was used as a vector to achieve TBK1 overexpression.The cells were cultured with high glucose medium (33 mmol/L) for 24 h, exposed to 94% N 2+ 5% CO 2+ 1% O 2 for 24 h in an incubator at 37℃ followed by 12 h reoxygenation in an incubator containing 5% CO 2 at 37°C to establish the model of H/R injury to cardiomyocytes subjected to high glucose.After reoxygenation, CCK-8 assay was used to detect cell viability, the activity of lactic dehydrogenase (LDH) in supernatant was detected using LDH kit, mitochondrial contents were determined using Mito-Tracter green fluorescent probe, and the expression of TBK1 and mitophagy-related proteins PINK1, Parkin, LC3B and P62 was detected by Western blot. Results:Compared with group C, the cell viability was significantly decreased, the activity of LDH in supernatant was increased, mitochondrial contents were decreased, the expression of TBK1, PINK1, Parkin and LC3B was down-regulated, and the expression of P62 was up-regulated in HG group and HG+ H/R group ( P<0.05). Compared with group HG, the cell viability was significantly decreased, the activity of LDH in supernatant was increased, mitochondrial contents were decreased, the expression of TBK1, PINK1, Parkin and LC3B was down-regulated, and the expression of P62 was up-regulated in group HG+ H/R ( P<0.05). Compared with group HG+ H/R, the the cell viability was significantly increased, the activity of LDH in supernatant was decreased, mitochondrial contents were increased, the expression of TBK1, PINK1, Parkin and LC3B was up-regulated, and the expression of P62 was down-regulated in group TBK1 ( P<0.05). Conclusion:The mechanism by which TBK1 overexpression reduces the H/R injury is related to restoring mitophagy in isolated mouse cardiomyocytes subjected to high glucose.

Objective To summarize the clinical features of patients with diffuse coronary artey diseases,and evaluate the clinical efficacy of off-pump coronary artery bypass grafting(OPCABG) combined with selective coronary venous bypass grafting (SCVBG).Methods Retrospectively analyzed the clinical data of 61 patients with diffuse right coronary stenosis undergoing operation of OPCABG + SCVBG from January 2007 to December 2013,and couducted the comparative study of the patients who underwent OPCABG during the same period based on propensity score.Patients were divided into SCVBG group(61 cases,underwent OPCABG + SCVBG) and control group(60 cases,matched by propensity score and underwent OPCABG without SCVBG).Results Compared with control group,the rate of myocardial infarction in SCVBG group was higher (67.2％ vs.46.7c％,P ＜0.05),the heart rate was faster[(69.92 ± 15.82) bpm vs.(64.48 ± 13.72) bpm,P ＜ 0.05],the low density lipoprotcin and triglyceride were higher[(2.67 ± 0.78) mmol/L vs.(2.37 ± 0.78) mmol/L (1.84 ± 0.79) mmol/L vs.(1.36 ± 0.60) mmol/L,both P ＜ 0.05] and the troponin I was higher in the first postoperative day [0.85 (0.29,3.15)μg/L vs.5.09 (2.02,13.03)μg/L,P ＜ 0.05].The perioperative(postoperative) mortality(1.6％ vs.0) and the long-term survival curve difference had no statistically significance(P ＞0.05).Conclusion Patients with coronary artery disease should pay more attention to the control of heart rate and blood lipids,poorly controlled heart rate and high blood lipids are the important factors for the development of coronary heart disease.The exact efficacv of selective coronary vein arterialization for diffuse coronary artery disease is confirmed through the small sample comparative study.

Objective To evaluate the application effect of telemedicine robot on the postoperative follow-up of liver transplantation recipients from donation after cardiac death (DCD). Methods A total of 100 recipients undergoing liver transplantation from DCD in the First Affiliated Hospital of Xi 'an Jiaotong University from January 2014 to December 2017 were recruited in this investigation. According to differnt follow-up patterns, all recipients were divided into the research group (n=50, follow-up by telemedicine robot) and control group (n=50, follow-up by traditional telephone). The compliance (medication compliance, self-monitoring, life compliance and follow-up compliance), follow-up time and follow-up satisfaction at postoperative 3 months of all DCD liver transplantation recipients were analyzed and statistically compared between research group and control group. Results The scores of medication compliance, self-monitoring, life compliance, follow-up compliance and the total score of compliance in the research group were significantly higher than those in the control group (all P < 0.05). The each follow-up time of liver transplantation recipients in the research group was (9±4) min, significantly shorter than (13±4) min in the control group (t=-4.452, P < 0.001). The score of satisfaction during postoperative follow-up in the research group was 19.8±2.6, significantly higher than 16.2±3.1 in the control group (t=6.234, P < 0.001). Conclusions The application effect of telemedicine robot on the postoperative follow-up of liver transplantation recipients from DCD is satisfactory, deserves widespread application in clinical practice. It is expected to become an indispensable part of the postoperative follow-up of liver transplantation recipients from DCD.

Objective: To explore the mechanical changes and distributions of pressure in each characteristic intervertebral disc after short segment unilateral pedicle screw fixation in Chinese mini-pigs. Methods: Six characteristic spine segments of 6-week-old Chinese mini-pigs (T3-4、T11-12、T15-L1、L3-4、L4-5 segments with adjacent upper and lower vertebrae) were chosen as experimental models. A biomechanical machine and pressure sensitive film were used to measure the pressure on the vertebral columns when they were subjected to pressures of 200 N as unfixed group. Compression was carried out under vertical, 5 °flexion, 5 °extension and 5 °lateral bending, respectively. Then the PCF (posterior cervical fixation) system were fixed on all segments (left side) as fixed group, and biomechanical tests were repeated to obtain data. A Fujitsu densitometer (Japan) was used to measure the pressure on each direction of the pressure sensitive film. Results: In vertical pressures, 5° flexion and 5°extension conditions, the posterior pressure of T3-4、T11-12、T15-L1、L3-4 and L4-5 intervertebral discs were decreased after fixation, the differences were statistically significant; The fixed side pressures of T3-4、T11-12、T15-L1、L3-4 and L4-5 in the fixed group were significantly lower than those in the unfixed group in the corresponding segments and load conditions, and the differences were statistically significant. The concave disc pressures of T3-4、T11-12、T15-L1、L3-4 and L4-5 in the fixed group were 0.83±0.12, 0.93±0.12, 0.50±0.05, 0.60±0.10 and 0.55±0.08 MPa respectively, which were lower than those of the unfixed group 1.70±0.18, 1.79±0.14, 1.84±0.22, 1.74±0.28, 1.60±0.23 MPa, and the differences were statistically significant. The total disc pressure of the fixed group was significantly lower than that of the non-fixed group in vertical compression, 5 degree flexion and 5 degree extension, and the differences were statistically significant. Conclusion Unilateral pedicle screw fixation can decrease the pressure on fixed side of fixed group in all conditions and change the distribution of pressure. The posterior pressure decreased particularly. Short- segment unilateral pedicle screw fixation can decrease the average pressure of intervertebral disc, which is an excellent surgery in curing scoliosis in young children.