Objective To measure stress distribution of the main bone architecture of the normal adult cadaveric foot and discuss the effect of plantar ligament injury on stress distribution. Methods Seven fresh adult cadaveric feet were used and 10 strain gauges attached to the bones of the longitudinal foot arch,including the calcaneus,navicular,medial cuneiform,1-5 metatarsal trunk,the distal part of the tibia and fibular,respectively.After the loading Was added to 700 N by almighty test machine,resistance strainmeter was used to measure surface strain of these bones.The results were processed statistically. Results The strain was varied based on different bone segments attached and increased with loading.Tensile force was always found at the medial part of the navicular,the distal part of the tibia and fibular,while the others showed compression all the time.Peak strain was found at calcaneus.followed by the second and third metatarsal.Strain on the surface of the bone segments changed greatly with different ligament injury(P＜0.05).Conclusion The bone surface stress of the longitudinal foot arch changes significantly when the plantar ligament is injured.

A new method for chiral separation and purity inspection of landiolol hydrochloride and its stereoisomers was developed by ultra-performance convergence chromatography ( UPC2 ) . The mobile phase was the mixture of supercritical CO2 and methanol/n-butyl alcohol/acetonitrile (1:1:1, V/V) plus 0. 5%NH3?H2O. The separation was carried out on the Daicel CHIRALPAK? IF column (150 mm × 4. 6 mm, 3 μm) with a flow rate of 2. 8 mL/min at 50℃ using 223 nm as detection wavelength. Under the optimized experimental conditions, for R,R-stereoisomer, R,S-stereoisomer and S,R-stereoisomer, the detection limits (LOD, S/N=3) were 0. 3, 0. 4 and 0. 3 mg/L, the linear ranges were 2-300 mg/L, 5-300 mg/L and 2-300 mg/L, the recoveries of spike samples were 103. 4%±2. 5%, 91. 8%±2. 5% and 101. 7%±1. 5%, and the injection repeatabilities were 0. 06%, 0. 09% and 0. 08% (n=6), respectively. The experimental results demonstrate that the UPC2-based method can be used for the analysis and determination of landiolol hydrochloride and its stereoisomers.

Objective To evaluate the stability of the pelvic ring reconstruction using fibular autograft for periacetabular tumor type Ⅱ resection. Methods 6 adult cadaveric specimens were tested. The periacetabular tumor resection models were established according to Ennecking's type Ⅱ resection. The resected pelvic rings were reconstructed with double-fibular graft fixed by four internal fixation techniques including plates, pedicle-rods (PR), lateral-rods (LR) or sacral-iliac rods (SIR). Axial loading from the proximal L3 vertebral body was applied by MTS load cell in the gradient of 0～500 N in the double feet standing state. Images in front view were obtained using CCD camera. Based on Image J software, displacement of the first sacral vertebrae （S1） of the reconstructed pelvis and intact pelvis were calculated using digital maker tracing method with center-of-mass algorithm. Results The rotational movements and vertical displacement of S1 around the normal side femoral head of the reconstructed pelvis in coronary plane were found in simulated bilateral leg standing position. The average vertical load-displacement and load-angular rotation curve of S1 in coronary plane were approximately linear behavior under the vertical load 500 N. The average vertical displacement and angle of S1 in coronary plane had not overacted. The stability of axial direction and rotation had not changed significantly when reconstructed by LR or Plates compared with the intact pelvis, but the SIR did. Conclusion Plates and LR fixation were more stabile for periacetabular tumor type Ⅱ resection.

ObjectiveTo evaluate the efficacy of short-segment transpedicular fixation combined with augmentation vertebroplasty in treatment of thoracolumbar burst fractures. MethodsFrom November 2006 to September 2009, 37 patients with thoracolumbar burst fracture were admitted and received transpedicular fixation combined with calcium sulfate cement augmentation vertebroplasty, and the clinical data including fracture types, complications and following-up results were collected for analysis. The multimethod evaluation strategies involved the anterior vertebral body height, the sagittal Cobb's angle, the restoration of nervous function, internal fixation failure, visual analogue scale (VAS) and Oswestry disability index (ODI) were retrospective analyzed. Results All patients were followed up for average 19 months (range, 14-37). There were no internal fixation failure, loss of reduction, neurological complications in all the patients. In 16 patients with partial neurologic deficits, 14 initially improved at the final follow-up, with no deterioration of neurologic functions. The mean time of calcium sulfate cement obvious absorption and union was 3 months and 5 months postoperatively, respectively. The anterior vertebral body height was 55.40％before surgery and 85.46％ after surgery on average, ended up with 82.35％. The sagittai Cobb's angle was improved from 22.45° to 6.86°, ended up with 9.66° on average. The mean VAS and ODI at the final followup were respectively 1.2 and 20.4 on average. ConclusionShort-segment transpedicular fixation combined with augmentation vertebroplasty appears to be effective in achieving stable biomechanics with high security,which seems to be a feasible option in the management of thoracolumbar burst fractures.

Objective: To evaluate the clinical effectiveness of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for single-level lumbar spondylolisthesis treatment with bilateral Spotlight tubular channels. Methods: A total of 21 patients with lumbar spondylolisthesis whom underwent MIS-TLIF via bilateral Spotlight tubular channels were retrospectively analyzed from October 2014 to November 2015. The 21 patients included 11 males and 10 females ranged from 35 to 82 years (average aged 60.7 years). In term of spondylolisthesis category, there were 18 cases of degenerative spondylolisthesis and 3 cases of isthmic spondylolisthesis. With respect to spondylolisthesis degree, 17 cases were grade Ⅰ° and 4 cases were grade Ⅱ°. Besides, 17 cases at L_4-5 and 4 cases at L₅-S₁were categorized by spondylolisthesis levels. Operation duration, blood loss, postoperative drainage and intraoperative exposure time were recorded, functional improvement was defined as an improvement in the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) was also employed at pre and post-operation (3 months and the last follow-up), to evaluate low back and leg pain. Furthermore, to evaluate the recovery of the intervertebral foramen and of lumbar sagittal curvature, average height of intervertebral space, Cobb angles of lumbar vertebrae and operative segments, spondylolisthesis index were measured. At the last follow-up, intervertebral fusion was assessed using Siepe evaluation criteria and the clinical outcome was assessed using the MacNab scale. Radiographic and functional outcomes were compared pre- and post-operation using the paired T test to determine the effectiveness of MIS-TLIF. Statistical significance was defined as P<0.05. Results: All patients underwent a successful MIS-TLIF surgery. The operation time (235.2±30.2) mins, intraoperative blood loss (238.1±130.3) ml, postoperative drainage (95.7±57.1) ml and intraoperative radiation exposure (47.1±8.8) were recorded. Different significance between 3 months post-operative follow-up and pre-operation was exhibited (P<0.01) in respects of lumbar VAS (t=11.1, P<0.01) and leg VAS (t=17.8, P<0.01). Moreover, final follow-up compared with pre-operation, and final follow-up compared with 3 months post-operative follow-up, VAS scores were also statistical difference (P<0.01). At the final follow-up, there were significant differences compared with pre-operation in ODI scores (t=30.1, P<0.01). Comparison between 3 months post-operative follow-up and pre-operation, statistical distinctions were demonstrated (P<0.05) in terms of mean height of intervertebral space (t=-10.9, P<0.01), the Cobb angles of lumbar vertebrae (t=-2.4, P<0.05), operative segments Cobb angles (t=-5.2, P<0.01) and Lumbar spondylolisthesis incidence (t=17.1, P<0.01). In addition, there was statistical difference between final follow-up and pre-operation (P<0.05) as well. For instance, mean height of intervertebral space (t=-10.5, P<0.01), the Cobb angles of lumbar vertebrae (t=-2.7, P<0.05), operative segments Cobb angles (t=-4.2, P<0.01) and Lumbar spondylolisthesis incidence (t=18.6, P<0.01) were involved. All spondylolisthesis vertebrae were restored completely. Lastly, at the last follow-up, 12 cases of grade 1 and 7 cases of grade 2 fusion were present as determined by the Siepe evaluation criteria. McNab scale assessment classified 17 patients having excellent clinical outcome, 3 patients in good and 1 patient having a better clinical outcome. Conclusion MIS-TLIF with bilateral Spotlight tubular channels is a safe and effective approach for single segment lumbar spondylolisthesis.

Objective:To investigate the feasibility of single breath-hold TFE-EPI in non-contrast coronary MRA on 3.0 T MRI.Methods:Both single breath-hold TFE-EPI and free breathing TFE were conducted in 23 healthy volunteers. Acquisition time between the two sequences were compared by paired- t-test analysis. Signal-noise-ratio (SNR), contrast-noise-ratio (CNR),image artifacts and distortion,vessel acuity were evaluated on the aorta(Ao), right coronary artery proximal(RCA-pro), right coronary artery middle (RCA-mid), left anterior descending proximal(LAD-pro) and left circumflex proximal(LCX-pro). Nonparametric analyses were conducted for the comparison. Results:The acquisition time decreased 96.51% in TFE-EPI compared with TFE [(16.3±2.2)s vs.(466.9±101.3)s, t=21.49, P<0.01]. There was no statistical significance in SNR comparison in all the vessel evaluation (all the P>0.05). TFE-EPI showed better CNR in RCA-mid than TFE ( Z=2.65, P=0.008). TFE-EPI showed less image artifacts and distortion in RCA-mid than TFE ( Z=2.00, P=0.046). TFE-EPI also showed better vessel acuity in both RCA-pro and RCA-mid than TFE ( Z=3.88, P<0.001; Z=3.42, P=0.001). Conclusion:Single breath-hold TFE-EPI could greatly shorten scan time while ensuring image quality in coronal artery imaging and has a broad application in future.

Objective:To investigate the efficacy of 3D-printed quantitative bone implants assisting second-stage Masquelet technique for the treatment of long-segment bone defect following Gustilo type IIIB and IIIC tibial fractures.Methods:A retrospective case series analysis was made on 26 patients with long-segment bone defect following Gustilo type IIIB and IIIC tibial fractures treated in Wuxi Ninth People′s Hospital from July 2015 to December 2020, including 20 males and 6 females; aged 19-63 years [(46.5±4.5)years]. Gustilo classification was type IIIB in 23 patients and type IIIC in 3. In the first stage, all patients had thoroughly emergent debridement, removal of all free bone pieces, restoration of the length and force line plus externally fixion, and vacuum sealing drainage (VSD) of the residual wound. After 2-7 days, the external fixation was removed and replaced by internal fixation, with the bone cement filling in the defect area and the free flap covering the wound. The length of tibial bone defect was 5-14 cm [(6.3±0.4)cm], and the tibial defect volume was 12.2-73.1 cm 3 [(33.6±9.2)cm 3]. In the second stage (6-19 weeks after injury), the bone cement was removed, followed by autologous bone grafting. Prior to bone grafting, digital technology was used to accurately calculate the bone defect volume, and an equal volume of bone harvesting area was designe to produce the 3D printed osteotomy template. Bone grafting was conducted after bone removal according to the osteotomy template during operation. The success rate of one-time iliac bone extraction, bone harvesting time, and bleeding volume were recorded. Pain in the bone extraction area was evaluated by visual analogue score (VAS) at 1 day and 1 month after operation and at the last follow-up. Wound healing, complications, and bone healing were observed. Life quality was evaluated by health survey brief form (SF-36) including scores of physical component summary (PCS) and mental component summary (MCS) before bone grafting and at the last follow-up. Results:All the patients were followed up for 13-53 months [(32.3±12.5)months]. One-time iliac bone extraction was successful in all the patients. Bone harvesting time was 15-30 minutes [(21.0±2.5)minutes]. The bleeding volume was 50-120 ml [(62.3±29.0)ml]. The VAS was 1-4 points [(1.2±0.9)points] at 1 day after operation, higher than these (0.0±0.0)points at 1 month after operation and at the last follow-up (all P<0.01). Totally, 25 patients obtained wound healing after operation, except for 1 patient with superficial wound infection after bone grafting that was healed by dressing change. There was 1 patient with bone infection after 3 months of bone grafting that was healed by repeated surgery with Masquelet technique in the first and second stage. Besides, 2 patients had symptoms of cutaneous nerve injury in the iliac donor area. The time of bone healing was 4-7 months [(5.8±0.8)months]. The scores of PCS and MCS in SF-36 at the last follow-up were (73.6±12.8)points and (83.6±13.2)points, significantly higher than those before bone grafting [(46.8±0.5)points, (60.7±2.0)points] (all P<0.01). Conclusion:Second-stage Masquelet technique with 3D printed quantitative bone implants for the treatment of long-segment bone defect following Gustilo type IIIB and IIIC tibial fractures is associated with shortened bone harvesting time, attenuated pain, reduced complications, accelerated bone healing and improved function.

BACKGROUND:Early diagnosis and treatment of intervertebral disc degeneration is particularly important.Pyroptosis of nucleus pulposus cells plays an important role in the early process of intervertebral disc degeneration,but the role of pyroptosis-related molecules of nucleus pulposus cells in early intervertebral disc degeneration and related molecular markers are still unclear. OBJECTIVE:To explore the diagnostic and therapeutic value of differentially expressed genes related to pyroptosis during intervertebral disc degeneration. METHODS:Public datasets of the GEO database were integrated for differential analysis,and intersected with 33 pyroptosis-related genes previously reported.Using Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes,pathway enrichment analysis was performed in genes related to pyroptosis during intervertebral disc degeneration.Enrichment analysis of the intervertebral disc degeneration dataset was conducted using gene set enrichment analysis.To construct the immune cell spectrum in intervertebral disc degeneration samples,the correlation between the differentially expressed pyroptosis-related genes and immune cells was analyzed.Protein interaction networks were built.Screening of the Hub gene to identify key genes associated with intervertebral disc degeneration in protein interaction networks.The receiver operating characteristic curve of the differentially expressed pyroptosis-related genes was plotted,and the area under the curve was calculated.The clinical diagnostic value of target genes was explored.qRT-PCR was applied to verify the difference in the expression of pyroptosis-related genes between normal human nucleus pulposus cells and degenerated human nucleus pulposus cells with intervertebral discs. RESULTS AND CONCLUSION:(1)4426 differentially expressed genes associated with intervertebral disc degeneration were obtained,and 14 differentially expressed pyroptosis-related genes were obtained after the intersection.(2)Gene Ontology and Kyoto Encyclopedia of Genes and Genomes revealed important enrichment pathways,mainly related to inflammation,cell cycle,infection and NOD-like receptor pathway.Gene set enrichment analysis showed that pathways such as amino acid metabolism and P53 transcription regulation were significantly enriched in patients with intervertebral disc degeneration.Immune infiltration analysis suggested that the occurrence and development of intervertebral disc degeneration were closely related to immune cells.(3)A total of five Hub genes were screened,namely IL1-β,Caspase-1,AIM2,Caspase-5,and NLRC4.(4)Acquisition and identification of key biomarkers for intervertebral disc degeneration:After intersecting the two datasets of GEO with the pyroptosis-related gene,it was found that NLRP3 had significant expression differences,and the receiver operating characteristic curve showed that NLRP3 had clinical diagnostic significance.(5)qRT-PCR showed that the expression of Hub genes such as IL1-β,Caspase-5 and NLRC4 was significantly increased in the nucleus pulposus cells of intervertebral disc degeneration(P<0.05),and there was no difference in Caspase-1,AIM2 and NLRP3 expression(P>0.05).(6)It is suggested that cell pyroptosis plays an important mechanism in the occurrence and development of intervertebral disc degeneration,among which pyroptosis-related molecules NLRP3,IL1-β,Caspase-5 and NLRC4 have early diagnosis and treatment value.

Objective:To construct a prediction model of pancreatic fistula after pancreaticoduodenectomy and explore its application value.Methods:The retrospective case-control study was conducted. The clinicopathological data of 285 patients with periampullary diseases who underwent pancreaticoduodenectomy in the the First Affiliated Hospital of Harbin Medical University from January 2015 to September 2018 were collected. There were 183 males and 102 females, aged (56±14)years, with a range from 12 to 84 years. According to the random numbers showed in the computer, patients were randomly divided into training dataset consisting of 214 patients and validation dataset consisting of 71 patients, with a ratio of 3∶1. The training dataset was used to construct prediction model, and the validation dataset was used to evaluate performance of prediction model. Observation indicators: (1) incidence of postoperative pancreatic fistula; (2) construction of prediction model of pancreatic fistula after pancreaticoduodenectomy; (3) validation of prediction model of pancreatic fistula after pancreaticoduodenectomy. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed by the t test. Measurement data with skewed distribution were represented as M (range), and comparison between groups was analyzed using the Mann-Whitney rank sum test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test. Univariate analysis and multivariate analysis were conducted using the Logistic regression model. The accuracy of prediction model was analyzed by drawing receiver operating characteristic curve and calculating area under curve (AUC). Results:(1) Incidence of postoperative pancreatic fistula: of 214 patients in the training dataset, 45 patients had postoperative pancreatic fistula, including 39 of grade B and 6 of grade C, respectively. (2) Construction of prediction model of pancreatic fistula after pancreaticoduodenectomy. Results of univariate analysis showed that body mass index(BMI), diameter of the main pancreatic duct on computed tomography (CT) scan, diameter of the main pancreatic duct by intraoperative exploration, pancreas texture, and level of amylase in ascites at the postoperative first day were related factors for pancreatic fistula after pancreaticoduodenectomy ( χ2=32.450, 15.789, 19.577, 4.559, Z=-7.962, P<0.05). Results of multivariate analysis showed that BMI>25 kg/m 2, diameter of the main pancreatic duct by intraoperative exploration <3 mm and level of amylase in ascites at the postoperative first day >2 651U/L were independent risk factors for pancreatic fistula after pancreaticoduodenectomy ( odds ratio=0.148, 4.286, 0.086, 95% confidence interval: 0.058-0.376, 1.736-10.580, 0.032-0.231, P<0.05). Based on results of multivariate analysis, a prediction model of pancreatic fistula after pancreaticoduodenectomy was built: the predicted value of pancreatic fistula=Exp[0.452-1.914(BMI)+ 1.455(diameter of the main pancreatic duct by intraoperative exploration)-2.451(level of amylase in ascites at the postoperative first day)]/1+ Exp[0.452-1.914(BMI)+ 1.455(diameter of the main pancreatic duct by intraoperative exploration)-2.451(level of amylase in ascites at the postoperative first day)]. The model had the AUC of 0.888 (95% confidence interval : 0.832-0.943, P<0.05). (3) Validation of prediction model of pancreatic fistula after pancreaticoduodenectomy: in the validation dataset, the prediction model of pancreatic fistula after pancreaticoduodenectomy had the AUC of 0.868 (95% confidence interval: 0.780-0.957, P<0.05). There was no significant difference in the AUC between the training dataset and validation dataset ( Z=0.514, P>0.05). Conclusions:BMI>25 kg/m 2, diameter of the main pancreatic duct by intraoperative exploration <3 mm and level of amylase in ascites at the postoperative first day >2 651 U/L are independent risk factors for pancreatic fistula after pancreaticoduodenectomy. Construction of a prediction model of pancreatic fistula after pancreaticoduo-denectomy can effectively predict the risks of postoperative pancreatic fistula.

Objective:To establish UPLC fingerprint method and 2 contents determination methods of Buddleja officinalis; To provide a reference for improving the quality control standard and evaluation of Buddleja officinalis from different habitats.Methods:UPLC method was used to establish the fingerprints of 17 batches of Buddleja officinalis. The similarity evaluation, clustering analysis, principal component analysis and orthogonal partial least squares discriminant analysis were used to compare the quality differences of Buddleja officinalis from different habitats. The contents of acteoside and linarin in Buddleja officinalis were determined.Results:There were 12 common peaks in UPLC fingerprints of Buddleja officinalis, six of which were identified as echinacoside, acteoside, cynaroside, isoacteoside, linarin, and apigenin. The fingerprint similarity of 17 batches of Buddleja officinalis was more than 0.9; Buddleja officinalis from different habitats were classified into 2 groups. Five differential markers were determined by OPLS-DA analysis. The order of significance was acteoside > peak 3 > echinacoside > isoacteoside > linarin. Edgeworthia chrysantha was identified by the method of fingerprint as counterfeit. The results of content determination showed that the content of Buddleja officinalis in Hubei and Sichuan was the high and stable.Conclusion:The method can effectively analyze the differences of Buddleja officinalis from different habitats, and provide reference for the quality control of Buddleja officinalis.