Conducting polymers play important roles in tissue engineering and biomaterials. This paper introduces their syntheses and applications to medical engineering.

To observe the changes in hemorheology, endotoxin and TNF ? in blood after hemoperfusion(HP) with adsorbent immobilized polymyxin B (PMB) on sepsis in rats. Wistar rats were randomly divided into three groups:LPS+HP+PMB,LPS+HP and LPS. All the rats received intravenously injection of lipopolysaccharide (LPS, Escherichia coil O111:B4,1mg/kg). Plasma of the rats in the group of LPS+HP+PMB was passed through a column containing sepharose coated activated charcoal immobilized polymyxin B at the 4th hour after LPS injection. The treated plasma was transfused bak after being mixed with blood cells. In LPS+HP group, the column did not contain immobilized polymyxin B. The animals of LPS group received LPS only. Quantitative endotoxin determination in blood was done with limulus amebocyte lysate test,TNF ? of the plasma assayed with ELISA, and hemorheology parameters were also observed after hemoperfusion. In LPS+HP+PMB group, the concentration of plasma was significantly decreased after hemoperfusion, but it was still significantly higher than the baseline value, and there was a decrease of blood cell ratio after hemoperfusion. The results suggest that specific adsorbent could remove endotoxin in the circulation and improve hemorheology.

BACKGROUND: Previous researches indicate that ADp14ARF transfecting positive tumor cell line of p53 can inhibit the proliferation; in addition, the inhibitory effect is superior to transfection negative tumor cell line of p53. Whether simultaneous transfection of p14ARF and p53 genes can increase expression and accumulation of p53 and accelerate apoptosis of tumor cells needs further studies.OBJECTIVE: To construct double plasmid expression vector plRES-p14ARF-p53 by using gene engineering so as to observe the inhibitory effect on proliferation of osteogenic sarcoma cells.DESIGN: Randomized controlled observation.SETTING: Department of Orthopaedics, Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology.MATERIALS: The experiment was carried out in the Public Laboratory Platform, Immune Researching Room, Basic Medical College, Tongji Medical College, Huazhong University of Science and Technology from January 2005 to October 2006. Human osteogenic sarcoma MG-63 cells were provided by Cell Laboratory, Immune Researching Room, Tongji Medical College, Huazhong University of Science and Technology. plRES-p53 plasmid and plRES vector containing p53total-length gene order were provided by Wuhan Jingsai Biology Company.METHODS: Based on gene engineering, p14DNA (0.5 kb) was amplified from cultured L02 cells of normal human hepatic cells into plRES vector. Recombinant plasmid plRES-p14ARF-p53 was determined with polymerase chain reaction (PCR) and restriction enzyme and transfected into human osteogenic sarcoma MG-63 cells through mediation of liposome to screen positive clones. Otherwise, cells were divided into three groups, including blank control group (MG-63cells), blank vector control group (stably transfecting plRES-neo cells) and p14ARF-p53 group (stably transfecting plRES-p14ARF-p53 cells). ① DNA content and cycle of tumor cells were measured by using flow cytometry before and after transfection. ② Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to detect quantitative and semi-quantitative expression of p53 and p14ARF protein in tumor cells after stable transfection. ③Thiazole blue chromatometry and growth curve were used to observe proliferation.MAIN OUTCOME MEASURES: ① DNA content and cycle of osteogenic sarcoma cells; ② expressions of p53 and p14ARF protein in tumor cells; ③ proliferation.RESULTS: Double plasmid expression vector plRES-p14ARF-p53 was constructed successfully. ① DNA content and cycle of osteogenic sarcoma cells: Flow cytometry demonstrated that tumor cells mainly stayed in G1 phase after transfection. ② Protein expression: RT-PCR and Western blot indicated that p14ARF and p53 gene independently expressed in target cell mRNA and protein, respectively. ③ Cell growth: At 24, 48, 72 and 96 hours after MG-63 transfection, inhibitory rates of tumor cells were 33.43%, 69.37%, 66.19% and 75.26%, respectively, which was significant difference as compared with blank vector control group (P ＜ 0.01).CONCLUSION: Wild p53 and p14ARF can synergistically inhibit the proliferation and accelerate the apoptosis of osteogenic sarcoma cells.

Adult ; Air Pollutants ; adverse effects ; Humans ; Male ; Military Medicine ; Monitoring, Physiologic ; Noise, Occupational ; adverse effects

Diagnosis, Differential ; Female ; Humans ; Knee Joint ; pathology ; Middle Aged ; Sarcoma, Synovial ; pathology ; Tomography, X-Ray Computed

OBJECTIVE: To summarize the effects of glial cell line-derived neurotrophic factor (GDNF) on ischemia damage to nerve tissue and discuss the possibility of GDNF in repair of spinal cord injury based on the development of microencapsulation technology.DATA SOURCES: A search of Medline from January 1996 to October 2000 was performed for the English articles related to GDNF, ischemia damage to nerve tissue, spinal cord injury and microencapsulation technology by using the key words "glial cell line-derived neurotrophic factor, ischemia damage to nerve tissue, spinal cord injury". Meanwhile, we retrieved Wangfang database for search of the related articles in Chinese by using the same keywords in Chinese.STUDY SELECTION: Articles including intervention group and control group were selected after first review, and those which were significantly non-randomized researches were excluded. Then, the full-texts of the enrolled articles were retrieved. Inclusion criteria: ①randomized controlled study; ②the experiment/clinical research including horizontal control group. Exclusion criteria: duplicated researches.DATA EXTRACTION: Totally 300 articles were selected but only 15 were in coincidence with conclusion criteria. 285 articles were excluded, 264 of them were duplicated and non-randomized researches, and 21 were review articles.DATA SYNTHESIS: GDNF can provide nutrition to dopamine nerve cell in rat's middle brain, so as to decrease dopamine nerve cell's death. Also GDNF can protect dopamine nerve cell in cerebral infarction rats from ischemic injury, inhibit the produce of nitrogen monoxide and reperfusion injury after ischemia. GDNF is an effective protective factor against ischemia damage. Microencapsulation technology has a bright future in treating endocrinopathic neural diseases, and GDNF can play a great role in the development of microencapsulation technology.CONCLUSION: GDNF is a protective factor against ischemia damage to nerve tissue, which can be enhanced by microencapsulation technology.There is a bright future for the research on GDNF in the clinical repair of spinal cord injury.

Objective To investigate the changes of gastric emptying in awake rats after acute myocardial infarction(AMI). Methods The male Wistar rats were submitted to thoracotomy followed by or not by occlusion of the left coronary artery. After 24 h, AMI(n=12)and sham groups (n=9)were fed in gavage(1 ml)with ~(99m)-Tc-DTPA labeled test meal. Half gastric emptying time (GET1/2) and 50min residual rate were measured by single photon emission computed tomography. The rats of AMI group were sacrificed after 50 min. Plasma level of motilin was measured by radioimmunoassay in AMI and sham group respectively(n=9). Results GET1/2 was significantly higher in AMI group[(23.1?4.7)min] than in sham group[(16.0?4.0)min](P

OBJECTIVETo explore the effect of Ginkgo biloba extract (GBE) on the function of alveolar polymorphonuclear neutrophils (PMN) in severe acute pancreatitis (SAP) rats complicated with lung injury (LI).

METHODSForty-eight adult SD rats were randomly divided into three groups, i.e., the sham-operation group, the SAP group, and the GBE treatment group, 16 in each group. The SAP model was successfully induced by retrograde injection of 5% sodium taurocholate solution into the biliopancreatic duct. Rats in the sham-operation group only received flipping of the duodenum. Those in the GBE treatment group received GBE intervention based on SAP model. Equal volume of normal saline was given to rats in the sham-operation group and the SAP group. Rats were sacrificed at 6 and 12 h after operation respectively. The lung tissue was sampled to evaluate the LI score. The wet/dry ratio (W/D) of lung tissues was detected. The activity of myeloperoxidase (MPO) was measured. Alveolar PMN was harvested by bronchoalveolar lavage. The content of neutrophil elastase (NE) in bronchoalveolar lavage fluid (BALF) was measured by enzyme-linked immunoabsorbent assay (ELISA). The percentage of CD11b/CD18 double positive PMN was detected using flow cytometry. The expression of intercellular adhesion molecule-1 (ICAM-1) and NE protein in the lung tissue was detected by Western blot.

RESULTSCompared with the sham-operation group, significant pathologic lesion occurred in the lung tissue of rats in the SAP group; the pathologic LI score, lung tissue W/D ratio, MPO, and NE content in BALF significantly increased, the expression of ICAM-1 and NE in the lung tissue was obviously up-regulated, and the percentage of CD11b/CD18 double positive PMN significantly increased (P < 0.01). Compared with the SAP group, pathological lesion of the lung tissue was obviously attenuated, and the above indices were all significantly declined in the GBE treatment group (P < 0.01).

CONCLUSIONSExpression of ICAM-1 in the lung tissue and the percentage of D11b/ CD18 double positive PMN were up-regulated in SAP rats complicated with LI, resulting in the adherence of PMN to pulmonary vascular endothelial cells, and then activating PMN to release NE and aggravate LI. GBE could alleviate LI through down-regulating the expression ICAM-1 and CD11b/CD18, and hindering the adherence and activation of PMN to pulmonary vascular endothelial cells.

Animals ; Bronchoalveolar Lavage Fluid ; cytology ; Ginkgo biloba ; chemistry ; Intercellular Adhesion Molecule-1 ; metabolism ; Lung Injury ; drug therapy ; etiology ; metabolism ; Neutrophils ; metabolism ; Pancreatic Elastase ; metabolism ; Pancreatitis ; complications ; drug therapy ; metabolism ; Plant Extracts ; pharmacology ; Rats ; Rats, Sprague-Dawley

Aim To determine whether membrane cytokeratin 8(CK8 )and BCRP expression cooperatively contributed to multidrug resistance(MDR)in MCF-7/MX cells.Methods MCF-7/MX cells were transfected with specific anti CK8-siRNAs and anti BCRP-siRNAs via LipofectAMINE2000.The expression of CK8 and BCRP was determined using Western blot,and membrane staining was observed by laser confocal microscopy.Sensitivity to chemical drugs was examined by Sulforhodamine B method.Results The expression levels of cell surface CK8 and BCRP were obviously reduced by siRNAs,and inhibition of CK8 and BCRP expression could effectively restore the sensitivity to drugs and reverse MDR phenotype of MCF-7/MX cells.Conclusions CK8 together with BCRP may play significant roles in conferring the multifactorial MDR phenotype of MCF-7/MX cells,but may act independently via potentially different mechanisms.Combinational approaches that target multiple drug-resistance-related molecules/pathways in cancer cells may represent more efficacious strategies to overcome MDR.

OBJECTIVETo explore the effect of fixation of Kirschner needle and thread cancellous bone screw through the sinus tarsi interstice for the treatment of calcaneal fractures.

METHODSFrom January 2009 to December 2012,20 patients with calcaneal fracture were treated by minimally invasive Kirschner wire and threaded cancellous bone screw fixation and bone graft,including 12 males and 8 females with an average age of 39 years old ranging from 21 to 65. Among them, 8 cases were left foot, 12 were right foot. According to Sanders's classification, 8 cases were type II, 10 cases were type III, 2 cases were type IV.

RESULTSAll patients were followed up from 6 to 16 months with an average of 12 months. The incision were healed. Böhler angle were increased from preoperative (17.75 +/- 4.22) degrees to postoperative (26.85 +/- 7.37) degrees (t = 4.308, P = 0.000). Gissane angle were reduced from preoperative (137.05 +/- 24.91) degrees to postoperative (113.75 +/- 13.17) degrees (t = 7.083, P = 0.000). At 3 months after operation, the scores of AOFAS were 85.50 +/- 7.99; the results were excellent in 5 feet and good in 11 feet, fair in 3 feet, and poor in 1 foot.

CONCLUSIONMinimally invasive fixation of Kirschner needle and thread cancellous bone screw fixation is a simple operation, it can get reliable fixation, easy to remove, low cost, less postoperative complications, and it is a good treatment of calcaneal fracture.

Adult ; Aged ; Bone Screws ; Bone Wires ; Calcaneus ; injuries ; surgery ; Female ; Fracture Fixation, Internal ; methods ; Humans ; Male ; Middle Aged