Objective To compare the effect of two different methods of cell seeding on spatial distribution and gene expression of hBMSCs in biocoral scaffold in vitro cultures. Methods The composite of hBMSCs and biocoral scaffold was prepared by traditional seeding (group A) and fibrin glue seeding (group B). The seeding efficiency was measured after 30 minutes of incubation in group B and after 3 hours in group A. At 2, 7, 14 and 21 days after culture, the samples were harvestedand the serial longitudinal sections were cut for each embedded composite. The sections were stained with DAPI and were measured using fluorescence microscope with apotome under serial optical sections. The cell number in every 10 × objective field was automatically measured by AxioVision image analysis software and levels (from seeding surface to bottom L1-L5) or columns (from centre to margin) for comparing cell distribution were set up. The specific osteogenic genes [osteonectin (ON), core binding factor α1 (Cbfα1), osteocalcin (OC)] expression was measured by RT-PCR. Results The seeding efficiency was significantly higher in group B (88.32% ± 4.2%) than in group A (66.51% ± 12.33%, P lt; 0.01). At 2 days after culture, the cell number from L1 to L4 decreased gradully in two groups (P lt; 0.05); in the cell number of different columns, there was no significant difference in group A (Pgt; 0.05) whereas significant difference in group B (P lt; 0.05); there was no significant difference in gene expression between two groups (P gt; 0.05). At 7 days after culture, the cell number was less than that at 2 days in group A and there was significant difference among levels (P lt; 0.05). The cell number and osteogenic gene expression increased sharply and there appeared uniform cell distribution in group B (P gt; 0.05). The gene expression of ON and Cbfα1 in group B was higher than that in group A (Plt; 0.05). At 14 days after culture, the cell number in levels or columns in group A decreased sharply and was less than that at 7 days (P lt; 0.05); whereas the cell number was similar to that at 7 days in group B (P gt; 0.05). The OC gene expression reached the highest level in group B at 14 days. The gene expression was higher in group B than in group A (P lt; 0.05). At 21 days after culture, there was significant difference in the cell number among levels and in the gene expression between group A and group B (P lt; 0.05); there was no significant difference in the cell number among columns in two groups (Pgt; 0.05). In addition, the cell number of most levels and columns in group B was more than that in group A at 7, 14 and 21 days after culture (P lt; 0.05). Conclusion More uniform cell distribution with rapid prol iferation and osteogenic differentiation is available in different levels or columns of scaffold by fibrin glue seeding than by traditional seeding.
ObjectiveTo investigate the associations of preoperative red cell distribution width (RDW) with mortality and morbidity in patients underwent liver transplantation. MethodsThis investigation was a retrospective study, the patients underwent liver transplantation met the inclusion criteria from June 2017 to May 2020 in the West China Hospital of Sichuan University were enrolled. The patients were divided into RDW≤14.5% group and RDW>14.5% group according to the normal RDW critical value (14.5%). The propensity score matching (PSM) was used to adjust the baseline characteristics. The primary outcome was 1-year mortality. The secondary outcomes included 1-year survival, 30-day mortality, incidence of early allograft dysfunction, acute kidney injury, renal replacement therapy, and pulmonary complications, as well as ICU stay and postoperative hospital stay. ResultsA total of 303 patients who met the analysis conditions were included. After PSM, 57 patients in each group were matched. There were no significant differences between the two groups in the baseline data such as the gender, age, body mass index (BMI), initial diagnosis, MELD score, Child-Pugh grade of the recipients, and the gender, age, and BMI of the donors (P>0.05). The 1-year [22.8% (13/57) versus 5.3% (3/57), χ2=7.27, P=0.007] and 30-day [15.8% (9/57) versus 3.5% (2/57), χ2=4.93, P=0.026] mortality of the patients with RDW >14.5% were higher than that of the patients with RDW ≤14.5% . The Kaplan-Meier survival curve showed that the 1-year survival of the patients with RDW ≤14.5% after liver transplantation was better than that of the patients with RDW >14.5% [hazard ratio=4.75, 95%CI (1.78, 12.67), P=0.007], but there were no significant differences between the two groups in the incidence of early graft dysfunction, acute renal injury, renal replacement therapy, and pulmonary complications, as well as postoperative hospital stay and ICU stay (P>0.05). ConclusionPreliminary results of this study indicate that preoperative RDW of patients underwent allogeneic liver transplantation is associated with1-year mortality, 30-day mortality, and 1-year survival.
Objective To establ ish sophisticated three-dimensional finite element model of the lower cervical spine and reconstruct lower cervical model by different fixation systems after three-column injury, and to research the stress distribution of the internal fixation reconstructed by different techniques. Methods The CT scan deta were obtained from a 27-year-old normal male volunteer. Mimics 10.01, Geomagic Studio10.0, HyperMesh10.0, and Abaqus 6.9.1 softwares were usedto obtain the intact model (C3-7), the model after three-column injury, and the models of reconstructing the lower cervical spine after three-column injury through different fixation systems, namely lateral mass screw fixation (LSF) and transarticular screw fixation (TSF). The skull load of 75 N and torsion preload of 1.0 N•m were simulated on the surface of C3. Under conditions of flexion, extension, lateral bending, and rotation, the Von Mises stress distribution regularity of internal fixation system was evaluated. Results The intact model of C3-7 was successfully establ ished, which consisted of 177 944 elements and 35 668 nodes. The results of the biomechanic study agreed well with the available cadaveric experimental data, suggesting that they were accord with normal human body parameters and could be used in the experimental research. The finite element models of the lower cervical spine reconstruction after three-column injury were establ ished. The stress concentrated on the connection between rod and screw in LSF and on the middle part of screw in TSF. The peak values of Von Mises stress in TSF were higher than those in LSF under all conditions. Conclusion For the reconstruction of lower cervical spine, TSF has higher risk of screw breakage than LSF.
It has been found that in biological studies, the simple linear superposition mathematical model cannot be used to express the feature mapping relationship from multiple activated grid cells' grid fields to a single place cell's place field output in the hippocampus of the cerebral cortex of rodents. To solve this problem, people introduced the Gauss distribution activation function into the area. We in this paper use the localization properties of the function to deal with the linear superposition output of grid cells' input and the connection weights between grid cells and place cells, which filters out the low activation rate place fields. We then obtained a single place cell field which is consistent with biological studies. Compared to the existing competitive learning algorithm place cell model, independent component analysis method place cell model, Bayesian positon reconstruction method place cell model, our experimental results showed that the model on the neurophysiological basis can not only express the feature mapping relationship between multiple activated grid cells grid fields and a single place cell's place field output in the hippocampus of the cerebral cortex of rodents, but also make the algorithm simpler, the required grid cells input less and the accuracy rate of the output of a single place field higher.
Objective To investigate the procedure and clinical effect of revascularization for arterial occlusion in lower extremity. Methods From July 1998 to March 2005, 29 cases of arterial occlusion were treated by microsurgery. Of 29 cases, there 22 males and 7 females, aging 22-86 years, including 9 cases of thromboangiitis obliterans(TAO), 17 cases of arterial sclerosis obstruction(ASO) and 3 cases of diabetic foot(DF). The location was the left in 17 cases, the right in 11 cases and both sides in 1 case. All cases were inspected by color-Doppler ultrasonic scanning before operation. The cases of ASO and DF were checked with MRA. The results of examinations showed that the locations of arteriostenosis and obstruction were: in 9 cases of TAO, the distal superficial femoral artery in 3 cases, popliteal artery in 5 cases, bilateral dorsal metatarsal artery in 1 case; in 17 cases of ASO, common iliac artery in 2 cases, external iliac artery in 4 cases, femoral artery in 10 cases and popliteal artery in 1 case; and were all superficial femoral artery in 3 cases of DF. DSA examination confirmed that there was appropriate outflow in 15 cases. Basing on the location and extent of the arterial occlusion, 11 cases were treated by the primary deep vein arterializing, 16 cases by arterial bypass distribution and 2 cases of extensive common iliac arterial occlusion were amputated in the level of 1/3 distal thigh. Results The postoperative duration of follow-up for all cases was 3 months to 7 years. In 9 cases of TAO, 2 healed by first intention after deterioration, 4 healed after changing dressing and 3 had fresh soft tissue growth after debrided superficial secondary necrosis. In 17 cases of ASO, 13 healed by first intention, 2 healed after changing dressing and 2 were amputated. In 3 cases of DF, 2 healed after changed dressing and debrided, 1 was aggravated with the second toe necrosis. Conclusion Performing primary deep veinarteriolization and arterial bypassdistribution is effective for treatment of arterial occlusion of lower extremity. The arterial reconstructive patency rate can be improved by microsurgical treatment.
ObjectiveTo evaluate the safety of photoelectric guided navigation unilateral puncture of the percutaneous kyphoplasty (PKP) in the treatment of thoracolumbar osteoporotic vertebral compression fracture (OVCF).MethodsA randomized controlled clinical research was performed between June 2015 and January 2017. Eighty-five cases of OVCF were treated with photoelectric guided navigation unilateral puncture of the PKP (trial group, 43 cases) or C arm fluoroscopy unilateral puncture of the PKP (control group, 42 cases) respectively. There was no significant difference in gender, age, disease duration, segmental fracture, AO classification, bone mineral density, and preoperative visual analogue scale (VAS) score between 2 groups (P>0.05). The concordance rate of puncture path and design path, the incidence of pedicle wall breaking, the incidence of bone cement leakage, and the rate of bone cement distribution center were observed and calculated on postoperative CT images; the intraoperative X-ray exposure frequency, frequency of puncture, operation time, VAS scores before operation and at 2 days after operation, and postoperative blood vessel or nerve injury were recorded and compared.ResultsThe intraoperative X-ray exposure frequency and puncture frequency in trial group were significantly less than those in control group (P<0.05), but there was no significant difference in operation time between 2 groups (t=0.440, P=0.661). The VAS scores of 2 groups at 2 days after operation were significantly improved when compared with preoperative ones (P<0.05), but there was no significant difference in VAS score at 2 days after operation between 2 groups (t=0.406, P=0.685). All the patients were followed up 6-18 months (mean, 10 months). No blood vessel or nerve injury occurred in 2 groups. The incidence of pedicle wall breaking, the incidence of bone cement leakage, the concordance rate of puncture path and design path, and the rate of bone cement distribution center in trial group were 2.33% (1/43), 2.33% (1/43), 86.05% (37/43), and 88.37% (38/43) respectively, all showing significant differences when compared with those of control group [19.05% (8/42), 21.43% (9/42), 45.24% (19/42), and 50.00% (21/42) respectively] (P<0.05).ConclusionIntraoperative photoelectric guided navigation unilateral puncture of the PKP can improve the success rate of target puncture and reduce the incidence of pedicle wall breaking effectively, and achieve better bone cement distribution and better security.
ObjectiveTo summarize the blood routine indexes and predictive systems that can predict the severity of acute pancreatitis (AP). MethodThe recent domestic and foreign literatures on the predictive value of blood routine indexes for the severity of AP were reviewed.ResultsFrom the current research results at domestic and foreign, independent blood routine indexes such as red blood cell distribution width, average platelet volume, hematocrit (TCT), platelet (PLT) count, platelet distribution width, percentage of immature granulocytes (IG%), and some blood routine calculation indexes such as neutrophil to lymphocyte ratio (NLR), PLT to lymphocyte ratio (PLR), red blood cell distribution width to PLT ratio (RPR), neutrophil-monocyte product, and so on, all had different predictive value for the severity of AP. In addition, multiple prediction modes such as blood routine indexes combined with some serological indexes or other scoring systems could also be used to predict the severity of AP. In general, the predictive value of the NLR, IG%, and HCT on the severity of AP had been unanimously recognized by researchers. However, the conclusions of related studies on the predictive values of PLT, PLR, and RPR on the severity of AP were still controversial. ConclusionsAt present, there are a variety of blood routine indexes can be used to predict severity of AP, but their predictive values are different. Further researches are still needed.
Objective Metal wear products cause the aseptic loosening of joint prosthesis. To investigate the effect of metal ions Co2+ and Cr3+ on the osteoblast apoptosis, cell cycle distribution, and secretion of alkal ine phosphatase (ALP), and to search a method to prevent and treat aseptic loosening. Methods The mouse calvarial osteoblasts (MC3T3-E1) were cultured in vitro to 3-5 generations (5 × 105 cells/ mL) and divided into 2 groups: the experimental group and the controlgroup. The osteoblasts were cultured in α-MEM medium containing 10%FBS (the control group), and the mixed solution ofCoCl2 and CrCl3 was added after the osteoblasts cultured in α-MEM medium containing 10%FBS attached completely (the experimental group). At 12, 24, and 48 hours after culture, the osteoblast apoptosis and the cell cycle distribution were assessed by flow cytometry; and ELISA method was appl ied to detect ALP content in serum supernatant. Results At 12, 24, and 48 hours after culture, the apoptosis rates in the experimental group (13.90% ± 0.52%, 14.80% ± 0.41%, and 13.40% ± 0.26%) were significantly higher than those in the control group (8.56% ± 0.31%, 8.19% ± 0.24%, and 2.15% ± 0.11%), (P lt; 0.05); G2M (dividing phase) distribution ratio significantly decreased and G0G1 (dormancy stage) distribution ratio significantly increased when compared with those in the control group (P lt; 0.05); and the absorbency (A) values of ALP were 0.955 ± 0.052, 0.624 ± 0.041, and 0.498 ± 0.026 in the exprimental group, and were 1.664 ± 0.041, 1.986 ± 0.024, and 2.192 ± 0.041 in the control group, showing significant differences between 2 groups (P lt; 0.05). Conclusion Metal ions Co2+ and Cr3+ have a marked effect on osteoblasts cell cycle distribution, which can make most of the cells to be in dormancy stage (G0G1), up-regulate the apoptosis rate and inhibit the releasion of ALP from osteoblasts.
Stress distribution of denture is an important criterion to evaluate the reasonableness of technological parameters, and the bite force derived from the antagonist is the critical load condition for the calculation of stress distribution. In order to improve the accuracy of stress distribution as much as possible, all-ceramic crown of the mandibular first molar with centric occlusion was taken as the research object, and a bite force loading method reflecting the actual occlusal situation was adopted. Firstly, raster scanning and three dimensional reconstruction of the occlusal surface of molars in the standard dental model were carried out. Meanwhile, the surface modeling of the bonding surface was carried out according to the preparation process. Secondly, the parametric occlusal analysis program was developed with the help of OFA function library, and the genetic algorithm was used to optimize the mandibular centric position. Finally, both the optimized case of the mesh model based on the results of occlusal optimization and the referenced case according to the cusp-fossa contact characteristics were designed. The stress distribution was analyzed and compared by using Abaqus software. The results showed that the genetic algorithm was suitable for solving the occlusal optimization problem. Compared with the reference case, the optimized case had smaller maximum stress and more uniform stress distribution characteristics. The proposed method further improves the stress accuracy of the prosthesis in the finite element model. Also, it provides a new idea for stress analysis of other joints in human body.
Objective To monitor the distribution of blood perfusion during aortic arch aneurysm surgery under double arterial lines with single pump. Methods We retrospectively analyzed the clinical data of 37 patients underwent aortic arch repair or reconstruction between September 2012 and April 2014. There were 9 females and 28 males at mean age of 48.1±10.8 years ranging from 19.0-72.0 years.We took double arterial lines with single pump for cardiopulmonary bypass (CPB) during the operation and we monitored the perfusion tube flow of both the upper and lower body by blood flow detector. Cerebral blood perfusion was measured by transcranial cerebral Doppler and near-infrared spectroscopy cerebral oxygen saturation (rSO2). Results The mean CPB time of all 37 patients was 195.8±40.5 minutes ranging from 136.0-277.0 minutes and the mean duration time of selective antegrade cerebral perfusion (SCAP) was 21.6±5.6 minutes ranging from 5.0-35.0 minutes. During cooling and rewarming phases, the part of blood flow through axillary artery cannulation ranged from 31.5% to 40.8% of the whole body perfusion. The blood flow of SACP was increased to 15.0 ml / (kg·min) in 2 patients with significantly lower rSO2 and middle cerebral artery blood flow during SACP, and they had an uneventful recovery process after surgery. There were another 2 patients recorded abnormal situation of rSO2 without interventions. One patient died and the other one recovered with compications of spinal cord. Conclusions The technique of double arterial lines with single pump is reasonable and effective. The cerebral perfusion monitoring is helpful to detect abnormal perfusion during aortic arch aneurysm surgery.