BACKGROUND:The creep characteristics of cancellous bone from necrotic femoral head are important for clinical artificial joint replacement.Therefore,it is necessary to study mechanical properties of cancellous bone at 45°direction.OBJECTIVE:To compare creep properties of normal femoral head and necrotic femoral head at 45°direction based on three-parameter model established creep equation METHODS:A total Of 8 normal and 8 necrotic femoral heads were used.The cancellous bone was harvested at 45° and subjected to creep test on electronic universal testing machine.With simulated temperature field of human body temperature at36.5℃.stress was imposed on the samples by an increase of 5%/s for 7 200 seconds.100 experimental data were collected,and stress relaxation equation was calculated using three-parameter model.RESULTS AND CONCLUSION:The creep curve of the femoral head of normal and necrotic changes was exponential relation.Changes were fast in the first 600 seconds,and strain increased slowly with time,finally entered into balance stage.7 200 s creep of cancellous,bone from necrotic femoral head was less than normal femoral head cancellous bone.Three-parameter model calculation is simple and can well fit the creep of changes in the femoral head.The establishment of such idealized equation quantitatively shows poor visco-elasticity of the necrotic femoral head.

Objective: To assess the peculiarity in fluorine-18 fluorodeoxyglucose (FDG) uptake in patients with bronchial alveolar carcinoma. Methods: From December, 1998 to April, 2002, 22 patients with bronchial alveolar carcinoma (BAC) were imaged with FDG-PET (positron emission tomography) before surgery. Their maximum and mean standard uptake value (SUVmax and SUVmean ) of tumor and SUV of normal lung (SUVlung) were measured. Results: All tumors were detected by FDG-PET. FDG uptake of tumor was higher than that of normal lung (P

Objective To investigate the effect of natural killer (NK) cells treated by serum of severe preeclampsia patient on the function of endothelial cells.Methods Fifteen patients with severe preeclampsia and 15 normal pregnant women from the Obstetrics department,Shengjing Hospital,China Medical University were admitted into this case-control study from January 1,2006 to December 31,2008.NK cells from healthy non-pregnant woman were incubated with 20% serum from severe preeclampsia patients or normal pregnant women for 20 hours.Then,human umbilical vein endothelial cells ( HUVEC) and serum-treated NK cells were co-incubated for 24 hours.Apoptosis of HUVEC was checked by flow cytometry and electronic microscope.Endothelin-1 (ET-1) levels in the supernatants of HUVEC and NK cells were examined by radioimmunologic method.Results In severe preeclampsia group,the percentage of early apoptosis cell (Annexin V-FITC+ /PI+ ) was (23.81±4.79)%,that of late apoptosis cell (AnnexinV-FITC+/PI+ ) was (3.29±1.04) %,while those were (16.59±5.13)% and (2.24±0.72)% respectively in normal pregnant group (P＜0.01).There was no significant difference in dead cells (Annexin V-FITC- /PI+ ).Under electronic microscope,typical morphologic changes of apoptosis were shown in severe preeclampsia group.Level of ET-1 in

Objective To investigate the alteration of nuclear factor kappa B( NF-κB) and tumor necrosis factor-a (TNF-α) mRNA and protein in hippocampus in chronic constrictive injury (CCI) model of rats. Methods Seventy-six male Wistar rats were randomly divided into 2 groups ( n = 38): the CCI group which received the chronic constriction injury and the sham group which received the sham operation as control. The mechanical and thermal nociceptive thresholds were assessed with paw withdrawal latency (PWL) to von Frey filaments and radiant heat at 1d before and ld,4d,7d,14d and 28d after CCI operation. Five animals were sacrificed at each time point for real-time polymerase chain reaction (real-time PCR) and another three animals sacrificed at 7d postoperation for immunofluorescence histochemical staining. Results The thresholds to mechanical and thermal stimuli decreased obviously after operation in CCI group. The expressions of TNF-α and NF-κB mRNA began to increase at ld( (2.079 ±0. 104)times and 4d( ( 1.640 ± 0.064) times) after operation and reached the peak at 7d ((2.748 ±0.147)times, (2.010 ±0.096)times) ,then the expressions of TNF-a mRNA began to decrease,while the expressions of NF-kB mRNA maintained at a high level throughout the experiment. The result of immunofluorescence histochemical staining revealed that NF-kB and TNF-α protein expressions at 7 day increased significantly on the hippocampus,which was consisted with NF-κB and TNF-a mRNA levels. Conclusion The activation NF-κB and TNF-α in hippocampus may be involved in the procession of neuropathic pain.

The non-specific accumulation and release of drugs are the main factors affecting the therapeutic effect as well as causing toxic side effects of chemotherapeutic drugs. Nowadays, the application of nanotechnology and responsive drug release is an important strategy to improve the tumor-specific accumulation of drugs and reduce their side effects. In this study, an α-enolase targeted peptide (ETP)-modified polyethylene glycol poly-lysine block copolymer loaded with oxaliplatin prodrug was synthesized first, and then, polymer-coating Fe₃O₄ nanoparticles were prepared by phase transfer dialysis method to improve the blood circulation stability and tumor targeting of oxaliplatin. At the same time, the physicochemical properties, reductant-responsive drug release, cellular uptake, tumor targeting and other biological functions of ETP modified oxaliplatin-loaded Fe₃O₄ nanoparticles were studied in vitro and in vivo. First, the results of reductant-triggered drug release study showed that the drug-loaded nanoparticles could achieve rapid release of more than 80% of the prototype oxaliplatin within 3 h under the reduction conditions simulating the tumor cytoplasmic microenvironment. Secondly, the results of flow cytometry showed that the modification of ETP could increase the ratio of cellular uptake of drug-loaded nanoparticles in tumor cells, and the way that drug-loaded nanoparticles endocytosed by tumor cells were mainly through the energy-dependent and receptor protein and fossin-mediated endocytosis pathway. The animal procedures were approved by the Institutional Animal Care and Use Committee of School of Pharmacy of Fudan University. Moreover, the results of pharmacokinetic experiment showed that the area under the curve (AUC_0-∞) of oxaliplatin could be significantly increased by nano-formulation which was about 5 times than that of free oxaliplatin. Besides, the pharmacokinetic results also showed that the drug-loaded Fe₃O₄ nanoparticles constructed by covalent linkage and chelation had good overall stability in vivo. Finally, the in vivo imaging results showed that ETP modification could increase tumor accumulation of drug-loaded nanoparticles, which would be conducive to the efficacy of oxaliplatin in tumor lesions. In summary, the oxaliplatin-loaded Fe₃O₄ nanoparticles with the capability of reductant-responsive drug release have good drug release characteristics, blood circulation stability and tumor targeting ability, and have the potential to improve the anti-tumor therapeutic effect of oxaliplatin.

Objective:To analyze risk factors for the rupture of basilar tip aneurysms (BTA) using morphological parameters assessed on CTA.Methods:The clinical data and CTA imaging characteristics of 62 patients with BTA from March 2016 to November 2020 in Huanhu Hospital of Tianjin were analyzed retrospectively. The patients were divided into un-rupture ( n=44) and rupture ( n=18) groups according to whether the BTA ruptured. The morphological parameters of aneurysms were measured and recorded. The number, shape and orientation of aneurysms were analyzed by χ 2 test between the two groups. The length (H max), height (H p), neck width (N D), aspect ratio (AR), size ratio (SR), angle of aneurysms (AA), flow angle (FA), basilar vessel angle (BVA), the angle between the proximal long axis of bilateral posterior cerebral artery P1 segment (P1-P1 angle), the angle between the proximal long axis of bilateral superior cerebellar arteries and bifurcation angle (the sum of the angle between the basilar artery and the bilateral posterior cerebral arteries) were analyzed by independent-sample t test between the two groups. On the basis of univariate analysis, logistic regression was used to identify the independent risk factors for BTA rupture. ROC curve analysis was further performed. Results:BTA with irregular shape was more likely to break (χ 2=5.412, P<0.05). The H max[(4.18±2.11)mm], N D [(3.06±1.75)mm], P1-P1 angle (148°±18°) in the rupture group were smaller than those in the un-rupture group [(6.38±2.21)mm, (5.20±1.59)mm, 178°±25°], with statistically significant difference ( P<0.05). While AR (1.19±0.13), BVA (82°±11°), and bifurcation angle (212°±18°) in the rupture group were larger than those in the un-rupture group (1.05±0.18, 70°±10°, 181°±27°), with statistically significant difference ( P<0.05). The logistic regression analysis showed that the shape of aneurysms (β=4.878, OR=11.418, P=0.019), BVA (β=0.165, OR=1.177, P=0.043), and P1-P1 angle (β=-0.223, OR=1.080, P=0.029) were independent risk factors for BTA rupture. The ROC curve analysis showed that the cut-off value of BVA and P1-P1 angle to predict the BTA rupture were 76.7° and 158.5°, and area under curve (AUC) were 0.79 and 0.86, respectively. The AUC of combined BVA with P1-P1 angle was 0.89. Conclusion:The shape of aneurysms, BVA and P1-P1 angle are independent risk factors for BTA rupture. BTA are prone to rupture when the shape of aneurysm is irregular, BVA>76.7 ° and P1-P1 angle<158.5 °.

Objective To summarize our experience in the diagnosis and management of popliteal artery entrapment syndrome (PAES). Methods This is a retrospective study on 10 patients (13 limbs)who were admitted for symptoms of claudication and the diagnosis of popliteal entrapment was established either with angiography,computed tomographic angiography,magnetic resonance angiogram or during the operation in recent 7 years (2002-2009).All patients were treated surgically. Results The mean age at the time of presentation was (25 ±7) years old (range,17-41 years).Claudication was the most frequent presenting symptom (12 limbs).The surgical procedures consisted of simple musculotendinous dissociation in 1 limb,thrombectomy with balloon angioplasty in 1 limb,musculotendinous dissociation plus thromboendarterectomy with autogenous saphenous vein (ASV)patch angioplasty in 2 limbs,ASV graft interposition or bypass in 6 limbs and graft interposition or bypass in 3 limbs.At a median follow-up of (35 ±27) months (range,2 months-7 years),there were no intraoperative or long-term postoperative complications and all the patients were cured. Conclusions PAES is an unusual but important cause of peripheral vascular insufficiency especially in young patients.A combined approach is necessary for diagnosis.Popliteal artery release alone or with vein bypass or reconstruction is the treatment of choice.

Objective To provide a device and an effective method for tail vein injection in mice. Methods Doing the tail vein injection in mice with the self-designed device which is consisted of constant temperature part, lighting part and holding part.The difficulty and time of injection with and without the device were compared.Results It was faster and more accurate to perform the tail vein injection in mice with this self-designed device.Conclusion Using this self-designed device can significantly improve the efficiency and save the injection time.

Objective:To investigate the differences in related indices of ulcerative colitis (UC) respectively induced by free drinking and intragastric administration of dextran sodium sulfate (DSS) in mice to provide experimental reference for the optimization of UC model.Methods:Totally 30 C57BL/6 mice were randomly divided into the normal control group,free drinking group and intragastric administration group with 10 ones in each.The mice drank water freely with free drinking or intragastric administration of 3% DSS solution at the dose of 4 g·kg-1·day-1 for 7 days to establish the UC model.The differences in disease activity index (DAI),histological damage sore and activity of myeloperoxidase (MPO) among the groups were compared.Results:Two mice died during the experiment in the free drinking group,and DAI of survival mice was (8.8±1.6).There was no death of mice in intragastric administration group,and DAI was (9.0±0.8),and there was no significant difference in DAI between the groups (P>0.05),while the coefficient of variation in the free drinking group was higher than that in the intragastric administration group (18.7 vs 8.6).The colonic histological damage score of the free drinking group and the intragastric administration group was 24.8±4.2 and 27.0±2.8,respectively,which was typical inflammatory change with no significant difference (P>0.05),while the coefficient of variation of the free drinking group was higher than that of the intragastric administration group (16.9 vs 10.4).MPO of the normal control group,free drinking group and intragastric administration group was (0.41±0.03),(2.32±0.34) and (2.05±0.18) U·g-1,respectively.Compared with the normal control group,significant difference in MPO was shown in the free drinking group and the intragastric administration group (P<0.01),while there was no significant difference in MPO between the groups (P>0.05),and the coefficient of variation in the free drinking group was higher than that in the intragastric administration group (14.7 vs 8.8).Conclusion:Both free drinking and intragastric administration of DSS can successfully induce the UC model in mice.Compared with the free drinking group,the intragastric administration group has low mortality rate and low coefficient of variation.Therefore,intragastric administration has more advantages than free drinking in inducing the UC model in mice.

Objective To investigate the effect of remote ischemic postconditioning on brain injury after asphyxial cardiac arrest-resuscitation in rats.Methods Sixty-nine male Sprague-Dawley rats were randomly divided into 3 groups (n =23 each) using a random number table:sham operation group (group S),asphyxial cardiac arrest-resuscitation group (group CA-CPR),and remote ischemic postconditioning group (group RIPost).The animals were anesthetized with intraperitoneal 1％ pentobarbital 40 mg/kg,intubated and mechanically ventilated.Asphyxia was induced by occlusion of the tracheal tube and resuscitation was started 8 min later.In RIPost group,RIPost was produced by 3 cycles of 15 min occlusion of the right hind femoral artery-15 min release of the right hind femoral artery after restoration of spontaneous circulation (ROSC).Neurological deficits were evaluated and scored at 24 h,72 h and 7 days after ROSC.Neuron specific enolase (NSE) concentration in serum was assessed at 48 h after ROSC by ELISA.At 3 days after ROSC,the number of viable neurons in hippocampal CA1 region was recorded (by N issl's staining).Morris water maze test was used to quantify spatial learning and memory deficits after ROSC.Results Compared with group S,the neurological deficit score at each time point and the number of viable neurons in hippocampal CA1 region were significantly decreased,the NSE concentration in serum was increased,the escape lantency was prolonged,and the target quadrant residence time percentage and distance percentage were decreased in CA-CPR and RIPost groups.Compared with group CA-CPR,the neurological deficit score at each time point and the number of viable neurons in hippocampal CA1 region were significantly increased,the NSE concentration in serum was decreased,the escape lantency was shortoned,and the target quadrant residence time percentage and distance percentage were increased in group RIPost.The damage to neurons in hippocampal CA1 region was significantly mitigated in group RIPost as compared with group CA-CPR.Conclusion Remote ischemic postconditioning can reduce brain injury after asphyxial cardiac arrest-resuscitation in rats.