BACKGROUND:The guinea pig is considered to be the most useful spontaneous model for evaluating primary osteoarthritis in humans because of its similar knee joint structure and close histopathologic features to those of humans. OBJECTIVE:To investigate the pathological process of spontaneous knee osteoarthritis in guinea pigs by analyzing the histopathology of the total knee joint of guinea pigs aged 1 to 18 months. METHODS:Eight healthy female Hartley guinea pigs in each age group of 1,6,10,14,16,and 18 months old were selected.The quadriceps femoris was taken for hematoxylin-eosin staining,and the total knee joint was stained with hematoxylin-eosin and toluidine blue.The histopathology of the cartilage,subchondral bone,synovium,meniscus,and muscles were observed under light microscope.Mankin's score and synovitis score were compared,and the correlation analysis was conducted. RESULTS AND CONCLUSION:As the guinea pig age increased,the Mankin's score increased(P<0.05),and the pathological score of synovitis also gradually increased(P<0.05),and there was a significant positive correlation between the two(r=0.641,P<0.001).The incidence rate of subchondral bone marrow lesion in 18-month-old guinea pigs was 50%,and the incidence of meniscus injury was 37.5%.In addition,osteophyte and narrowing of the joint space were observed,and only a few guinea pigs had inflammation in the quadriceps femoris.To conclude,guinea pigs develop significant cartilage defects,synovial inflammation,subchondral bone lesions,meniscus injury,osteophyte formation,and joint space narrowing as they age,all of which are similar to the pathological processes of primary knee osteoarthritis in humans,making it an ideal model of spontaneous knee osteoarthritis.

A 20-year-old male patient presented to the Department of Dermatology of Peking Union Medical College Hospital with complaints of an 8-year history of facial scarring, swelling of the lower limbs, and a 4-year history of scalp thickening. Physical examination showed thickening furrowing wrinkling of the skin on the face and behind the ears, ciliary body hirsutism, blepharoptosis, and cutis verticis gyrate. Both lower limbs were swollen, especially the knees and ankles. The skin of the palms and soles of the feet was keratinized and thickened. Laboratory examination using bone and joint X-ray showed periostosis of the proximal middle phalanges and metacarpals of both hands, distal ulna and radius, tibia and fibula, distal femurs, and metatarsals.Genetic testing revealed two variants in SLCO2A1, c.1658T > A and c.96+4A > C.Through multidisciplinary consultation, we confirmed the diagnosis of pachydermoperiostosis.

Objectives:This study aims to investigate the impact of different Low-Density Lipoprotein cholesterol(LDL-C)levels on progression of intermediate coronary stenosis,and the associated risk factors leading to the progression of such lesions. Methods:Data were collected on 219 consecutive patients admitted at the Fuwai Central China Vascular Hospital from January 2020 to February 2021,underwent angiographic examinations and diagnosed with intermediate coronary stenosis,with at least one follow-up angiography after 11 months.Offline quantitative flow ratio(QFR)analysis was performed on these cases.Patients were divided into two groups:LDL-C controlled group(LDL-C<1.8 mmol/L,148 patients with 191 vessels)and LDL-C uncontrolled group(LDL-C≥1.8 mmol/L,71 patients with 98 vessels).Coronary artery QFR and anatomical indicators such as minimal lumen diameter,minimal lumen area,percentage diameter stenosis,percentage area stenosis were compared within and between the groups.Further analysis was performed to identify influencing factors leading to changes in coronary physiological parameters derived from QFR. Results:Within the LDL-C controlled group,there was no significant difference in the QFR values of the vessels compared to baseline(P>0.05),whereas in the LDL-C uncontrolled group(P<0.05),a notable decline in QFR was observed.Patients in the LDL-C controlled group had lower rates of maximum diameter and area stenosis and higher minimum lumen diameter and area(all P<0.05).Through multifactorial Logistic regression analysis,it was found that a body mass index＞28 kg/m2,LDL-C≥1.8 mmol/L,and a history of myocardial infarction were independent risk factors leading to the decline in QFR(all P<0.05). Conclusions:It was found that patients in the LDL-C controlled group had higher coronary artery QFR,minimum lumen diameter and area,lower rates of maximum diameter and area stenosis.

OBJECTIVE To investigate the activation of xanthine oxidase(XO)from the human liver by vitamin K3 and the mechanism.METHODS Using human liver S9(0.1 g·L-1)as the source,XO was incubated with substrate xanthine of 0,2,4,8,and 16 μmol·L-1 at 37℃ for 90 min.The Michaelis constant(Km)of the reaction of xanthine oxidation was determined using the liquid chromatography diode array method.At the concentration of Km,the three-point method(1,10 and 100 μmol·L-1)was used to detect the activity of vitamin K3 activators.The multi-point method(vitamin K3 1,2,5,10,20,50,100,200 and 400 μmol·L-1)was adopted to determine the half effective concentration(EC50)of activated XO.Kinetic parameters(Km and Vmax)and the fit of double reciprocal curves were determined via vitamin K3 of 1/2EC50,EC50 and 2EC50.The changes in kinetic behavior at different concentrations of vitamin K3 were observed and their types of activation were analyzed.The interactions between XO and activator vitamin K3 were explored via molecular docking.RESULTS The Km of XO-mediated xanthine oxidation reac-tion was 4.71 μmol·L-1.As an activator of this reaction,vitamin K3 activated XO in a concentration-dependent manner(according to the logistic fitting formula y=A2+(A1-A2)/(1+(x/x0)^p),with an EC50 of 32.0 μmol·L-1.The kinetic parameters also changed after the addition of vitamin K3.The Km value decreased(4.71-1.34 μmol·L-1)with the increase of vitamin K3 concentrations,while the Vmax value increased(0.08-1.31 μmol·min-1·g-1),leading to an increase in Vmax/Km(17.0-977.6 mL·min·g-1).In addition,the double reciprocal curve fitting found that the activation type of vitamin K3 on XO was mixed.The molecular docking results showed that vitamin K3 bound to the molybdopterin domain of XO and maintained hydrogen bonding interactions with Arg599 and Ser605.CONCLUSION Vitamin K3 is an activator of XO,which can form hydrogen bonds with Arg599 and Ser605 in the XO domain,regu-late its affinity with the substrate xanthine,activate XO and increase the uric acid level.

Objective:To explore the related prognostic factors in patients with aortic dissection (AD) after surgery or interventional therapy, and to construct a multi-factor Cox regression analysis nomogram prediction model.Methods:The clinical data of patients diagnosed with AD in the emergency department of Affiliated Hospital of Jining Medical University of Shandong Province from January 2019 to December 2021 were collected to analyze retrospectively. The survival time was followed up, the survival curve was drawn by Kaplan-Meier method, the difference of survival rate among different Stanford types was tested by Log-Rank test, and Cox regression univariate and multivariate survival analysis was used to screen the prognostic factors. According to the results of multivariate analysis, the death risk nomogram model after AD was established, the differentiation of the model was evaluated by C-index, the accuracy of the model was evaluated by calibration curve, and the clinical benefit of the model was evaluated by decision curve analysis (DCA).Results:A total of 256 patients with AD were included, the mortality rate was 4.45% (37/256), and the overall survival rates at 3 months, 6 months and 12 months after operation were 90.23%, 87.50% and 85.55%, respectively. There was no significant difference in postoperative survival rate among AD patients with different Stanford types (χ 2=2.30, P=0.13). Cox multivariate regression analysis showed that history of hypertension ( HR=3.791, 95% CI 1.150-12.501, P=0.029), number of branch vessels involved ( HR=1.210, 95% CI 1.029-1.422, P=0.021), preoperative left ventricular ejection fraction (LVEF) ( HR=0.936, 95% CI 0.880-0.996, P=0.038) and perioperative complications ( HR=4.024, 95% CI 1.839-8.807, P<0.001) were independent prognostic factors in patients with AD. Furthermore, the predictive nomogram model of 3-month, 6-month and 12-month survival rate in patients with AD was constructed, and the C-index was 0.778. The calibration curve indicated that the accuracy of the model was good, and the clinical benefit of the DCA model was good. Conclusions:Hypertension history, the number of branch vessels involved, preoperative LVEF and perioperative complications are independent risk factors of postoperative death in patients with AD. The nomogram prediction model based on the above factors can be used to evaluate the postoperative survival of patients with AD.

Objective:To investigate the current situation of the use of transjugular intrahepatic portosystemic shunt (TIPS) for portal hypertension, which should aid the development of TIPS in China.Methods:The China Portal Hypertension Alliance (CHESS) initiated this study that comprehensively investigated the basic situation of TIPS for portal hypertension in China through network research. The survey included the following: the number of surgical cases, main indications, the development of Early-TIPS, TIPS for portal vein cavernous transformation, collateral circulation embolization, intraoperative portal pressure gradient measurement, commonly used stent types, conventional anticoagulation and time, postoperative follow-up, obstacles, and the application of domestic instruments.Results:According to the survey, a total of 13 527 TIPS operations were carried out in 545 hospitals participating in the survey in 2021, and 94.1% of the hospital had the habit of routine follow-up after TIPS. Most hospitals believed that the main indications of TIPS were the control of acute bleeding (42.6%) and the prevention of rebleeding (40.7%). 48.1% of the teams carried out early or priority TIPS, 53.0% of the teams carried out TIPS for the cavernous transformation of the portal vein, and 81.0% chose routine embolization of collateral circulation during operation. Most of them used coils and biological glue as embolic materials, and 78.5% of the team routinely performed intraoperative portal pressure gradient measurements. In selecting TIPS stents, 57.1% of the hospitals woulel choose Viator-specific stents, 57.2% woulel choose conventional anticoagulation after TIPS, and the duration of anticoagulation was between 3-6 months (55.4%). The limitation of TIPS surgery was mainly due to cost (72.3%) and insufficient understanding of doctors in related departments (77.4%). Most teams accepted the domestic instruments used in TIPS (92.7%).Conclusions:This survey shows that TIPS treatment is an essential part of treating portal hypertension in China. The total number of TIPS cases is far from that of patients with portal hypertension. In the future, it is still necessary to popularize TIPS technology and further standardize surgical indications, routine operations, and instrument application.

Objective:To analyze the treatment efficacy, safety and dose parameters of optimized hippocampus-avoidance prophylactic cranial irradiation (HA-PCI) in limited-stage small cell lung cancer (LS-SCLC) and explore the corresponding dosimetric parameters under the condition of narrowing the hippocampus avoidance region as hippocampus region plus 2 mm in three dimensions.Methods:Clinical data of patients with LS-SCLC receiving HA-PCI (hippocampus avoidance region defined as hippocampus region plus 2 mm in three dimensions) in Cancer Hospital Chinese Academy of Medical Sciences from August 2014 to June 2020 were retrospectively analyzed. Dose parameters of HA-PCI and adverse events were analyzed using descriptive statistics analysis. Changes of neurocognitive function, such as mini-mental state examination (MMSE) and Hopkins verbal learning test-revised (HVLT-R) scores, were evaluated by analysis of variance and Kruskal-Wallis H test. Overall survival (OS), progression-free survival (PFS) and intracranial PFS (iPFS) were calculated using Kaplan-Meier method. The cumulative incidence of local-regional recurrence (LRR), extracranial distant metastases (EDM), and locoregional recurrence (LR) were investigated under competing risk analysis. Results:A total of 112 patients were included, the median follow-up time was 50 months (95% CI: 45.61-54.38). The median volume of hippocampus was 4.85 ml (range: 2.65-8.34 ml), with the average dose ≤9 Gy in 106 patients (94.6%), ≤8 Gy in 92 patients (82.1%). The median volume of hippocampus avoidance area was 15.00 ml (range: 8.61-28.06 ml), with the average dose ≤12 Gy in 109 patients (97.3%), ≤10 Gy in 101 patients (90.2%). The 2-year cumulative LRR, EDM, LR rates were 16.9%, 23.2% and 28.5%, respectively. The 5-year cumulative LRR, EDM, LR rates were 23.2%, 26.9% and 33.3%, respectively. The 2-year iPFS, PFS and OS rates were 66.1% (95% CI: 57.9%-75.4%), 53.6% (95% CI: 45.1%-63.7%) and 80.4% (95% CI: 73.3%-88.1%), respectively. The most common grade I-Ⅱ adverse events were nausea (33.9%) and dizziness (31.3%), and only 1 patient developed grade Ⅲ nausea and dizziness. MMSE ( n=57) and HVLT-R tests ( n=56) showed no significant decline. Conclusions:Optimized HA-PCI can achieve similar dose limitation with favorable efficacy and light toxicity. No significant decline is observed in short-term neurocognitive function in evaluable patients.

Objective To design an experimental device for simulating the interface micro motion of bone trabecular prosthesis and carry out the finite element analysis.Methods The experimental device was composed of a screw-in cylinder with threads,a flexible hinge,a micro-motion rod,a trabecular prosthesis,a connecting rod and a fixation post.A model of the experimental device was constructed with SolidWorks software,and then imported into ABAQUS software to establish a finite element model.An axial displacement load was applied to the femur to analyze the effects of the position of the flexible hinge,the gap between the prosthesis and the femur and the length of the connecting rod on the micro motion.Results The interface micro motion produced by the experimental device increased with the distance of the flexible hinge from the lower end of the screwed-in cylinder;the gap between the prosthesis and the femur did not affect the interface micro motion when the gap was not lower than 20 μm;the interface micro motion rose with the length of the connecting rod.Conclusion The experimental device can accurately simulate the micro motion of different bone trabecular prosthesis interfaces,and can be used for studying the effect of the interface micro motion on osseointegration.[Chinese Medical Equipment Journal,2024,45(1):25-30]

OBJECTIVE To evaluate the consistency between the quetiapine LC-MS/MS kit and the laboratory-built method(reference method) in the detection results of quetiapine therapeutic drug monitoring. METHODS A total of 120 remaining plasma samples were collected from patients receiving quetiapine therapeutic drug monitoring from March to October in 2021. The plasma concentration of quetiapine was detected by kit and reference method respectively. The analysis of correlations and consistency was performed by outlier analysis, linear regression and Bland-Altman method. RESULTS No outliers were detected. The linear regression equation was Y=1.018X+4.400(r=0.998), indicating a good correlation. The Bland-Altman plot analysis showed good agreement between the two measurements. CONCLUSION The detection results of quetiapine LC-MS/MS kit and reference method are in good agreement. The kit can be used for clinical quetiapine treatment drug monitoring.

OBJECTIVE To establish the quality standard of Triadica cochinchinensis and to perform the acute toxicity study. METHODS Appearance properties, powder microscopic identification, and thin-layer chromatography(TLC) identification were researched. The specific chromatogram was established by HPLC. The content of cadmium(Cd), lead(Pb), arsenic(As), copper(Cu), and mercury(Hg) was determined by inductively coupled plasma-mass spectrometry(ICP-MS). Acute toxicity was studied by maximum dose. RESULTS The outer skin of herbs was dark brown, and the inner surface was light yellow brown and fibrous. Besides, crystal sheath fiber was common, and calcium oxalate clusters arranges in rows. In the TLC diagram of the test product, the fluorescent spots of the same color were displayed at the corresponding position of the control product(scopoletin, isofraxidin). Five common peaks were calibrated in the characteristic map and the three characteristic peaks(scopoletin, isofraxidin, dimethylfraxetin) were recognized. The content of the measured heavy metal elements was lower than the national limit standard. The linear correlation coefficient was R2 > 0.999. The precision, stability, repetitive RSD were < 10%. The average recovery rate of the added sample was 80%−120%, and the RSD was < 10%. The maximum dose of the acute toxicity test was 184.09 g·kg−1. The 14 d internal body mass, food intake, organ-body ratios, the serum glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, blood urea nitrogen, and creatinine were not significantly different by comparing with the normal controls. Therefore, no significant toxicity was observed. CONCLUSION The established standard can provide a reference for evaluating the quality of Triadica cochinchinensis. The heavy metal content of ten batches of medicinal materials is within the safe range. Acute toxicity test show that there is no obvious significant adverse teactions after oral administration, and the safe dose range is large, which can provide a reference for the subsequent development and utilization.