1.Carbon fiber-reinforced polyetgeretherketone for femoral head prosthesis and its stability:a biomechanical analysis
Zhihua JI ; Bingshen JIA ; Liyi ZHOU ; Kun FU ; Zhibin MENG ; Peng YU ; Dake YUN
Chinese Journal of Tissue Engineering Research 2017;21(15):2325-2330
BACKGROUND: Metal implants have been extensively applied in joint arthoplasty, but the stress shielding effect caused by its high elastic modulus results in a series of complications, such as bone resorption, bone atrophy and prosthesis loosening. Carbon fiber-reinforced polyetheretherketone (CF-PEEK) composites are anisotropic and exhibit more advantages used for prosthesis due to its low elastic modulus and high intensity.OBJECTIVE: To investigate the blood compatibility of CF-PEEK composites, and compare the biomechanical properties after arthroplasty between CF-PEEK composites and Co-Cr-Mo used for femoral head prosthesis. METHODS: (1) The blood compatibility of CF-PEEK composites was evaluated through hemolysis test. (2) Femoral samples from eight fresh cadavers were collected and randomly divided into two groups, followed by subjected to CF-PEEK and Co-Cr-Mo prosthesis replacement, respectively. The displacement between the prosthesis and bone was measured under loading 200, 400, 600, 800 and 1000 N, and the torsional strength after arthroplasty was detected.RESULTS AND CONCLUSION: (1) The hemolysis rate of the CF-PEEK composites was 3.23% < 5%, which was in line with the national standards for biological evaluation of medical devices. (2) The micromovement in distal prosthesis was significantly less than that of proximal prosthesis under different loads in both two groups (P < 0.05). (3) The torsion angle under different loads in the CF-PEEK group was significantly less than that in the Co-Cr-Mo group (P < 0.05), and the torsion stiffness in the CF-PEEK group was significantly higher than that in the Co-Cr-Mo group (P < 0.05). (4) To conclude,the CF-PEEK composites possess good blood compatibility and stability, which can be used as a prosthesis material.
2.Cardioplegia solution plus metformin protects isolated rat hearts
Xin DUAN ; Cun LONG ; Feilong HEI ; Kun YU ; Jinping LIU ; Bingyang JI
Chinese Journal of Thoracic and Cardiovascular Surgery 2017;33(1):44-48
Objective To evaluate the protective value of cardioplegia solution plus metformin in different cardiac arrest time and concentration of metformin in isolated rat hearts .Methods There were 36 male Sprague–Dawley rats divided into six groups randomly, according to the duration of cardioplegic arrest(30 min or 60min) and the concentrations of metformin(50μmol/L or 100 μmol/L) .Langendorff-perfused Sprague-Dawley rat hearts were perfused for 20 minutes with Krebs-Henseleit buffer followed by 30 or 60 minutes of crystalloid cardioplegia or plus metformin (50 or 100 μmol/L) and 60 minutes of reperfu-sion.The left ventricular performance was recorded at 5 time points.The expressions of AMPKαand phosphorylation of AMPKαwere detected by western Blot.The changes of myocardial mitochondria were observed under transmission electron mi-croscope.Results There were no significant differences in Con(A), 50(A) and 100(A) groups in LVDP, ±dp/dtmax and HR.Compared with Con(B) group subjected to 60 minutes of ischemia followed by 60 minutes of reperfusion, the 100(B) group significantly improved myocardial performance , and the ratio of p-AMPKα/AMPKαwas the highest in all 6 groups.The structure of myocardial mitochondria in 100(B) group was better protected than that of Con(B) group.Conclusion These findings suggested that the left ventricular performance was protected in rat heart perfused by cardioplegia plus 100 μmol/L after 60 minutes cardioplegic arrest .The mechanism may be the activation of AMPK and the protection of structures of myocardial mitochondria.
3.Correlations between HIV-1 subtypes and changes in CD4+T cell count over time
Kun FANG ; Xiaoshan LI ; You GE ; Yu JI ; Yue SONG ; Guoping DU ; Wenjuan YAN ; Pingmin WEI
Chinese Journal of Microbiology and Immunology 2017;37(6):461-466
Objective To understand the correlations between HIV-1 subtypes and changes in CD4+T cell count over time in patients with different subtypes of HIV-1 infection.Methods A total of 94 patients who were diagnosed with HIV-1 infection in Nanjing and received at least twice CD4+T cell counting test before antiretroviral therapy (ART) were recruited in this study.Descriptive analysis was used to present the rates of CD4+T cell decline for different HIV-1 subtypes.Logistic regression analysis and nonparametric test were conducted to investigate the factors responsible for CD4+T cell decline and to analyze the correlations between the rates of CD4+T cell decline and HIV-1 subtypes.Results The median monthly rate of CD4+T cell decline was-2.20 [interquartile range (IQR):-11.36-2.13] cell/μl.Of all patients,25.5% (24/94) had a significant decline (≥30%) in CD4+T cell count.Compared with the patients infected with CRF01_AE,those infected with CRF07_BC (OR=0.28,95%CI: 1.7-6.5) or other subtypes (OR=0.16,95%CI: 1.0-2.9) had a lower risk of significant decline in CD4+T cell count.In addition,results of the nonparametric test showed that the patients infected with CRF01_AE (M=-21.54,IQR:-30.97——11.92 cell/μl) had a faster CD4+T cell loss than those infected with CRF07_BC (M=-11.26,IQR:-14.06——5.63 cell/μl) (P=0.033).Conclusion HIV-1 subtype is associated with the rate of CD4+T cell decline.It is important to monitor the changes in CD4+T cell count in patients infected with CRF01_AE and to carry out timely ART.
4.Risk factors and outcomes of severe hemolysis during extracorporeal membrane oxygenation:a 5-year ;single-center retrospective analysis
Lin LYU ; Guodong GAO ; Jinxiao HU ; Qiang HU ; Jingxin YAO ; Cun LONG ; Feilong HEI ; Bingyang JI ; Jinping LIU ; Kun YU
Chinese Critical Care Medicine 2016;28(6):518-522
Objective To investigate the risk factors of severe hemolysis during extracorporeal membrane oxygenation (ECMO). Methods The clinical data of adult patients undergoing ECMO after cardiac surgery admitted to Fuwai Hospital from December 2010 to October 2015 were retrospectively analyzed. Demographic characteristics, renal function, primary disease, operation data, ECMO related data and outcomes were recorded. Patients were divided into normal free hemoglobin (FHB) group (FHB ≤ 500 mg/L) and severe hemolysis group (FHB > 500 mg/L) according to the FHB level during ECMO support. The parameters before and after ECMO support were compared between the two groups. Logistic regression was used to identify the independent risk factors of severe hemolysis. Results A total of 81 patients including 19 patients with severe hemolysis was enrolled, and 62 in normal FHB group. There was no difference in cardiopulmonary bypass (CPB) time, clamping time, lactate level before ECMO, cardiopulmonary resuscitation, intra-aortic balloon pump use and central catheter insertion between two groups. The maximums of serum creatinine (SCr) and FHB levels were higher in severe hemolysis group as compared with those in normal FHB group [maximal SCr (μmol/L): 281.02±164.11 vs. 196.67±87.31, maximal FHB (mg/L): 600 (600, 700) vs. 200 (100, 300)], the incidence of clots in circuit or oxygenator, infection, and hemofiltration in severe hemolysis group was increased [26.3% (5/19) vs. 4.8% (3/62), 31.6% (6/19) vs. 12.9% (8/62), 36.8% (7/19) vs. 14.5% (9/62), all P < 0.1]. As well as outcomes including the rate of site of surgery or intubation bleeding and acute renal failure [ARF, 57.9 % (11/19) vs. 30.6% (19/62), 94.7% (18/19) vs. 41.9% (26/62)], and the survival rate was lowered [10.5% (2/19) vs. 51.6% (32/62), all P < 0.05]. As result of univariate analysis, clots in circuit or oxygenator, infection and hemofiltration were associated with severe hemolysis. It was showed by logistic regression analysis that the clots in circuit or oxygenator was a risk factor of severe hemolysis during ECMO [odds ratio (OR) = 6.262, 95% confidence interval (95%CI) = 1.244-31.515, P = 0.026]. Conclusions The clots in circuit or oxygenator were independent risk factors of severe hemolysis during ECMO. Severe hemolysis can induce the increase of the rate of bleeding in the operation site or intubation and the rate of ARF, and decrease of the survival rate.
5.Influence of bicortical anchorage on the natural frequencies of dental implant.
Kun WANG ; De-hua LI ; Ji-xiang ZHOU ; Cong-ji ZHANG ; Bao-lin LIU ; Yu-long LI
West China Journal of Stomatology 2006;24(1):86-88
OBJECTIVETo investigate the influences of bicortical anchorage on values of natural frequencies of dental implants utilizing the 3-dimensional finite element analysis.
METHODSUsing the commercial code of Solidworks, 3-D models of a screw-shaped dental implant and a mandibular bone segment were generated. After the 3-D implant-bone complex was meshed by ABAQUS software, effects of bicortical anchorage on the buccolingual and axial first-order natural frequencies of the implant were computed.
RESULTSBicortical anchorage increased both the buccolingual and axial natural frequencies remarkably. As the bicortical anchorage got deeper, the frequencies correspondingly got higher.
CONCLUSIONBicortical anchorage can increase the buccolingual and axial primary stability of dental implants.
Dental Implantation, Endosseous ; Dental Implants ; Dental Stress Analysis ; Finite Element Analysis ; Humans ; Mandible
6.Expression of chemokine receptor CXCR4 in colorectal carcinoma and its relationship with clinicopathological parameters.
Liang YU ; Yun SHEN ; Ji-Kun LI ; Yu-Hao SUN ; Yi-Cheng WANG ; Jian-Hai ZHANG
Chinese Journal of Gastrointestinal Surgery 2008;11(5):482-486
OBJECTIVETo investigate the expression of chemokine receptor CXCR4 in colorectal carcinoma and its relationship with the clinicopathological parameters, and to reveal the role of CXCL12/CXCR4 in the invasion and metastasis of colorectal carcinoma.
METHODSCXCR4 expression was studied in 53 colorectal cancer tissues and 27 normal tissues by immunohistochemistry. Its relationship with clinicopathological characteristics of colorectal cancer patients were analyzed. The CXCR4 expression in tumor and normal specimens and its metastatic sites were assessed by RT-PCR and Western blot.
RESULTSFifty-three colorectal cancer patients,collected from July 2005 to February 2007 in our hospital,were enrolled in this study. CXCR4 was positive in 39 cancer tissue specimens(73.6%) and its high expression rate (in > 50% of cells) was 45.3%. High CXCR4 expression rate was significantly higher in patients with lymph node metastases (N(1)+N(2): 65.4%) than that in those without metastases(N(0) 25.9%). There were also associations between the high CXCR4 expression and the vascular and lymphatic vessel invasions (P<0.01). Meanwhile, there was a rising trend of high expression rate according to American Joint Committee on Cancer (AJCC) stage and pathologic grade,but no significant difference was found(P>0.05). There were no significant correlation of CXCR4 expression with clinicopathological parameters such as tumor location, tumor size, depth of tumor invasion(P>0.05). In addition, the CXCR4 mRNA expression in primary tumor specimens (n=27) from AJCC stage IIII( patients was significantly higher than that in normal tissues. CXCR4 mRNA expression of liver metastasis specimens(n=5) was significantly higher as compared with the primary colorectal cancer specimens(P<0.01).
CONCLUSIONSChemokine receptor CXCR4 is associated with the progression of colorectal carcinoma. High CXCR4 expression is associated with metastasis. The CXCL12-CXCR4 signaling pathway may be a potential novel target of therapy for patients with colorectal cancer.
Adult ; Aged ; Aged, 80 and over ; Colorectal Neoplasms ; metabolism ; pathology ; Female ; Humans ; Liver Neoplasms ; secondary ; Male ; Middle Aged ; Neoplasm Staging ; RNA, Messenger ; genetics ; Receptors, CXCR4 ; metabolism
7.Ablation of segmental glissonian pedicle by ultrasound-guided radiofrequency in precision liver resection in a porcine model.
Ji-ye CHEN ; Yu-kun LUO ; Kai JIANG ; Jia-hong DONG
Chinese Journal of Surgery 2012;50(6):547-550
OBJECTIVETo demonstrate the ablation of segmental glissonian pedicle by ultrasound-guided radiofrequency in precision liver resection in porcine model.
METHODSThe study was carried out on 6 Bama miniature pigs. Coagulative desiccation of the vessels feeding the segment to be resected was induced by introduction of a "cooled-tip" radiofrequency electrode under intraoperative ultrasound guidance at the level of the vessels. Then, an area of marked discoloration on the surface of the liver became obvious. Liver parenchymal transection followed without any form of hepatic inflow occlusion. Three segments (segment 3, 5, and 6) were resected on each pig. The criteria studied the local and general tolerance, the change of blood flow parameters of each segmental arterial and portal branches, and the microscopic appearance of the segmental arterial, portal and biliary tract branches. Using t test as the statistical methods.
RESULTSPostoperative mortality and morbidity were 0 and all serum parameters had normalized by 14 days. Demarcation area was obtained in 15 segments. The flow rate of the resected segmental portal branches was 0 cm/s after radiofrequency and the value of the arterial branches was (28 ± 18) cm/s which was significantly lower than pre-radiofrequency, which were (10.2 ± 3.0) cm/s and (60 ± 17) cm/s (t = 14.439, 5.502; P = 0.000). There was no significant difference in the flow rate of the remnant segmental arterial and portal branches among pre-radiofrequency, post-radiofrequency and 14 days after operation. On microscopic observation, the mean ablated length of segmental portal, arterial and biliary tract branches were (1.6 ± 0.4) cm, (1.2 ± 0.4) cm, and (1.7 ± 0.3) cm respectively.
CONCLUSIONSThe ablation of the segmental glissonian pedicle by ultrasound-guided radiofrequency is quick, safe and effective. The probe needs to be away from vessels feeding segments 1.5 cm at least to avoid thermal injuries.
Animals ; Catheter Ablation ; methods ; Female ; Hepatectomy ; methods ; Male ; Swine ; Swine, Miniature ; Ultrasonography
8.An accessory limb with an imperforate anus.
Kun Bo PARK ; Yeon Mee KIM ; Ji Yong PARK ; Mi Lim CHUNG ; Yu Jin JUNG ; So Hyun NAM
Annals of Surgical Treatment and Research 2014;87(4):213-216
Congenital accessory limbs are very rare anomalies with many causative factors. We describe the case of a 1-day-old female neonate-born to a healthy, 27-year-old mother-who presented with an accessory limb (foot) attached to the buttock and an imperforate anus. We also provide a review of the relevant literature.
Adult
;
Anus, Imperforate*
;
Buttocks
;
Extremities*
;
Female
;
Humans
9.Synaptic Reorganization of Dentate Mossy Fibers and Expression of Calcium Binding Proteins in Hippocampal Sclerosis of Temporal Lobe Epilepsy.
Sang Pyo KIM ; Seung Pil KIM ; Seung Che CHO ; Young Rok CHO ; Ji Min JEON ; Yu Na KANG ; Kun Young KWON ; Eun Sook CHANG
Korean Journal of Pathology 1998;32(5):328-336
This study was designed to identify expression of calcium-binding proteins and synaptic reorganizations of dentate mossy fibers in hippocampal sclerosis of human temporal lobe epilepsy. Hippocampal neuronal density was quantitively analyzed in temporal lobe epilepsy group (n=50) to investigate the degree of hippocampal sclerosis and it was compared with that of autopsy control (n=3). To verify the distribution of calcium-binding proteins in neurons of epileptic hippocampi, the parvalbumin (PV)-immunoreactive and calbindin-D28K (CB)-immunoreactive neurons were quantitively analyzed in each area of Ammon's horn by immunohistochemical stain. Also, to clarify synaptic reorganizations of the dentate mossy fibers, a part of each hippocampus was examined under light microscopy and transmission electron microscopy using Timm sulphide silver method. In epileptic hippocampi, severity of hippocampal sclerosis (HS) was graded four, which consisted of 3 cases with no HS, 6 mild HS, 12 moderate HS, and 29 severe HS. The hippocampal neuronal loss was most prominent in CA1, followed by CA4 and CA2. Expression of calcium-binding proteins was more prevalent in CA2 of all groups. The proportion of PV-immunoreactive neurons in CA1 and CA4 significantly increased in the moderate and severe HS group, whereas the proportion of CB-immunoreactive neurons did not correlated with the severity of HS. Timm granules were noted in inner molecular supragranular layer of dentate gyrus of epileptic hippocampi and they tended to increase in proportion along with the severity of hippocampal sclerosis. Transmission electron microscopy showed that supragranular Timm granules corresponded to synaptic terminals of mossy fibers. These results suggest that parvalbumin appears to have more protective effect against neuronal loss and that mossy fiber synaptic reorganization seems to play a major role in pathogenesis of hippocampal sclerosis of human temporal lobe epilepsy.
Autopsy
;
Calbindin 1
;
Calcium*
;
Calcium-Binding Proteins*
;
Dentate Gyrus
;
Epilepsy, Temporal Lobe*
;
Hippocampus
;
Humans
;
Microscopy
;
Microscopy, Electron, Transmission
;
Nerve Fibers, Myelinated
;
Neurons
;
Presynaptic Terminals
;
Sclerosis*
;
Silver
;
Temporal Lobe*
10.Identification of the related substances in docetaxel injection by LC-MS/MS.
Ya-Kun RAO ; Meng WANG ; Li DING ; Bing LIU ; Cheng JI ; Zheng-Yu YAN
Acta Pharmaceutica Sinica 2012;47(6):779-784
The related substances in docetaxel injection were identified by LC-MS/MS. Ethyl acetate was used to extract the injection to remove the pharmaceutical excipients. HPLC separation was carried out on a Hedera ODS-2 column (150 mm x 2.1 mm, 5 microm) with a mobile phase consisting of acetonitrile - 0.1% acetate acid aqueous solution (40: 60). Electrospray ionization source was set in the positive mode for the LC-ESI-MS/MS, and the ion monitoring modes were full scan and product ion scan. According to the mass spectra of the related substances, the fragment profiles were explained, and the chemical structures were elucidated. Docetaxel and its main related substances were well separated. Nine related substances in docetaxel injection were detected by LC-MS/MS. Their chemical structures were proposed, and four of them were identified in the docetaxel injection for the first time. The established LC-MS/MS method is effective in the separation and identification of the related substances in docetaxel injection. The test results are useful for its quality control.
Antineoplastic Agents
;
administration & dosage
;
analysis
;
chemistry
;
Chromatography, High Pressure Liquid
;
Drug Contamination
;
Injections
;
Molecular Weight
;
Quality Control
;
Spectrometry, Mass, Electrospray Ionization
;
Tandem Mass Spectrometry
;
Taxoids
;
administration & dosage
;
analysis
;
chemistry