1.Soluble expression and target study to brain of anti-TfR ScFv.
Bing YAN ; Heng-Qi ZHU ; Pei-Tang HUANG
Chinese Journal of Biotechnology 2004;20(3):342-347
The single-chain antibody gene (ox26-scFv) to transferrin receptor (TfR) was synthesized and amplified by three-step PCR. After sequencing, the gene was cloned into prokaryotic expression vector pTIG-Trx which carried thioredoxin (Trx) gene and a C-terminal His.tag. The Ox26-scFv proteins achieved 31% yields of total bacteria proteins at 20 degrees C, after 0.02mM IPTG induction using the strain E. coli BL21 (DE3). The soluble scFv proteins in cytoplasm suspension were about 35% and the inclusion bodies were about 65%. The soluble products were purified by immobilized metal chelation affinity chromatography (Ni-NTA), a single band with molecular weight 29 kD appeared on SDS-PAGE gel. Rat GH3 cell immunocytochemistry staining showed that Ox26-scFv protein could recognize and bind to transferrin receptor. Injected SD rats with Ox26-scFv proteins by tail veins, the antibodies were detected from brain tissues specially on the brain capillaries 4 h later which indicate that Ox26-scFv proteins have a good target function to brain capillaries and can permeate the blood-brain barrier mediated by the transferrin receptors.
Animals
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Antibodies
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administration & dosage
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genetics
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metabolism
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Antibody Formation
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Base Sequence
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Blood-Brain Barrier
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drug effects
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Drug Delivery Systems
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Genetic Vectors
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Molecular Sequence Data
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Rats
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Rats, Sprague-Dawley
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Receptors, Transferrin
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immunology
2.Construction, expression and preliminary pharmacokinetic analysis of IL-1ra mutants.
Yu-Xin WANG ; Zhi-Xin YANG ; Heng-Qi ZHU ; Xiao-Wei ZHOU ; Pei-Tang HUANG
Chinese Journal of Biotechnology 2006;22(3):472-476
Interleukin-1 receptor antagonist (IL-1ra), a member of IL-1 family, is a naturally occurring IL-1 inhibitor as "receptor antagonist", which blocks biological responses mediated by IL-1. Recombinant human IL-1ra (rhIL-1ra, Kineret) was introduced in clinical trials involving patients with RA. Between 2001 to approximately 2002, rhIL-1 ra was approved by the US Food and Drug Administration and the European Agency for the Evaluation of Medicine Procedure. Unfortunately, 10,000 to 100,000-fold excess amounts of IL-1ra are needed to relieve disease because minimal IL-1 can induce complete biological responses, and the dosage of 100 to approximately 150mg/day in a RA patient is so big that it greatly influence patients' physical, psychological and economical situation. In this study, IL-1ra mutants were established by site-specific mutagenesis to improve its stability. The sites of mutagenesis included R6 K7-AA,R93 K94-AA and K97 R98-AA. IL-1ra and its mutants were expressed in E. coli BL21 (DE3) using pTIG-Trx expressing system with the induction of IPTG. The recombinant proteins were purified by Ni2+ chelate chromatography and Sephadex G75 gel filtration chromatography. The activity of mutants is as high as IL-1ra. We characterized the pharmacokinetic profile of IL-1ra and its mutants. The third mutant's half life is 2.26 times than wt IL-1ra. The study has provided some approaches and experience for further research to improve the metabolism stability of IL-1ra.
Animals
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Escherichia coli
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genetics
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metabolism
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Female
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Humans
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Interleukin 1 Receptor Antagonist Protein
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biosynthesis
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genetics
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pharmacokinetics
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Mutagenesis, Site-Directed
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methods
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Mutant Proteins
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biosynthesis
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pharmacokinetics
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Recombinant Proteins
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biosynthesis
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genetics
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pharmacokinetics
3.Reconstruction of the acetabular in the Crowe III dysplastic hip.
Jing TANG ; Hong-yi SHAO ; Qi-heng TANG ; Qing LIU ; Hai-jun XU ; Yi-xin ZHOU
Chinese Journal of Surgery 2008;46(17):1303-1306
OBJECTIVETo investigate the method and the outcome of the acetabular reconstruction in the Crowe III dysplastic hip.
METHODSFrom January 2001 to June 2007, 43 cases (54 hips) were diagnosed osteoarthritis secondary to Crowe III dysplastic hip. Total hip arthroplasty was performed in all cases. The Harris score was 39 pre-operation. The method of the acetabular reconstruction included acetabular deepening (group A), medial-wall osteotomy (group B), femoral head bone grafting (group C). Radiography data and Harris score were taken to evaluate the clinical outcome.
RESULTSThe method of the acetabular reconstruction included acetabular deepening in 27 cases (34 hips), medial-wall osteotomy in 12 cases (15 hips), femoral head bone grafting in 4 cases (5 hips). Forty cases were followed up by the mean time of 29 months. The bone union time of the osteotomy and bone grafting were 4 - 5 months postoperation. In the three groups the obliquity angle of the cup were (41.0 +/- 7.5) degrees , (46.0 +/- 7.7) degrees , (39.0 +/- 11.0) degrees ; the anteversion angle of the cup were (10.0 +/- 2.8) degrees , (9.0 +/- 2.5) degrees , (4.0 +/- 1.9) degrees ; the rotation center of the hip was shift superiorly (8.4 +/- 3.6) mm, (7.3 +/- 2.6) mm, (1.2 +/- 0.5) mm; the rotation center of the hip were shift internally (7.0 +/- 1.5) mm, (9.9 +/- 1.7) mm, (-2.7 +/- 1.2) mm, and the Harris score were 89, 91, 86 at the follow up. The complication included deep venous thrombosis in 2 cases, pulmonary embolism in 2 cases, sciatic nerve palsy in 4 cases.
CONCLUSIONAcetabular deepening, medial-wall osteotomy, femoral head bone grafting can be used in reconstruction of the acetabular in the Crowe III dysplastic hip.
Acetabulum ; surgery ; Adult ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Hip ; methods ; Bone Transplantation ; Female ; Follow-Up Studies ; Hip Dislocation, Congenital ; complications ; surgery ; Humans ; Male ; Middle Aged ; Osteoarthritis, Hip ; etiology ; surgery ; Osteotomy ; Treatment Outcome
4.Eliminating impingement optimizes patellar biomechanics in high knee flexion.
Qi-heng TANG ; Yi-xin ZHOU ; Jing TANG ; Hong-yi SHAO ; Guang-zhi WANG
Chinese Medical Journal 2010;123(16):2244-2248
BACKGROUNDWe investigated the impact of eliminating the impingement between extensor mechanism and tibial insert on patellar tracking and patellar ligament tension in high knee flexion.
METHODSSix cadaveric specimens were tested on an Oxford-type testing rig. The Genesis II knee system was implanted into each specimen knee with the traditional tibial insert and high-flex insert successively. Compared to traditional insert, the high-flex insert was characterized with a chambered anterior post and a chambered anterior lip which eliminates patella-post and patellar ligament-anterior lip impingements. The patella was tracked with an NDI Optotrak Certus system. The patellar ligament tension was measured using a NKB S-type tension transducer.
RESULTSThere was a decrease of resultant patellar translation relative to the femur with statistically significant (P<0.05) at 90 degrees to 150 degrees of knee flexion and a decrease of patellar ligament tension with statistical significance (P<0.05) at 100 degrees, 120 degrees, 130 degrees, and 140 degrees of flexion using high-flex insert compared to traditional insert.
CONCLUSIONSEliminating the impingement between extensor mechanism and implant in high knee flexion altered patellar tracking and reduced patellar ligament tension, which would facilitate high knee flexion.
Biomechanical Phenomena ; Humans ; In Vitro Techniques ; Knee Joint ; physiology ; Ligaments, Articular ; physiology ; Patellar Ligament ; physiology ; Range of Motion, Articular ; physiology
5.Clinical results and peri-operative complications of total knee arthroplasty for patients with different ages.
Yi-Xin ZHOU ; Hong-Yi SHAO ; Jing TANG ; Qi-Heng TANG
Chinese Journal of Surgery 2009;47(11):833-836
OBJECTIVETo analyze the clinical results and complications of total knee arthroplasty (TKA) performed for patients with different ages.
METHODSFrom January 2004 to March 2005,212 patients (300 knees) were followed up, all patients were divided into 6 groups according to the age. All the complications and knee society scores (KSS) were documented and retrieved for analysis.
RESULTSKSS of all groups was significantly improved after TKA. The patients whose age was 70 years or older, and underwent bilateral TKA achieved the best improvement of knee function. The complication rate increased with the patients' age.
CONCLUSIONSTKA predictably alleviates knee pain and restores knee function. Aging itself does not compromise clinical results of TKA. However perioperative complication rate is a little bit higher in aged patient group and simultaneously bilateral TKA patient group.
Age Factors ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee ; Female ; Humans ; Male ; Middle Aged ; Postoperative Complications ; Retrospective Studies ; Treatment Outcome
6.Accuracy of three different electronic apex locators in determination of perforation with various conditions in vitro.
Yue-heng LI ; Zhi ZHOU ; Yu-qi ZHENG ; Ning GAN ; Yu-ying TANG ; Rui LI ; Jiao CHEN
West China Journal of Stomatology 2011;29(3):272-275
OBJECTIVETo evaluate accuracy of Propex, Raypex 5, Root ZX electronic apex locator in positions of the perforation with different irrigations in the root canal.
METHODSPerforation lengths were measured with Propex, Raypex 5, Root ZX electronic apex locators in 19 extracted human teeth embedded in model after simulate perforation preparation by ultrasonic ET40 and compared with the actual canal length measurements taken before embedding the teeth in model. Measurements were taken with the different canal contents. RESULTS; Propex, Raypex 5, and Root ZX could locate the positions of the perforation with different irrigations in the root canal. The differences between actual root canal perforation length and measured root canal perforation length of same electronic apex locators in different irrigations were no statistically significant (P > 0.05). Meanwhile, the differences between actual root canal perforation length and measured root canal perforation length of three kinds of electronic apex locators in same irrigations were not statistically significant (P > 0.05).
CONCLUSIONPropex, Raypex 5, and Root ZX electronic apex locators can detect perforation accurately.
Dental Pulp Cavity ; Humans ; In Vitro Techniques ; Molar ; Odontometry ; Root Canal Therapy ; Tooth Apex ; Tooth Root
7.Analysis of the failure mechanisms of the revision hip arthroplasties.
Liang ZHANG ; Yi-Xin ZHOU ; Xin-Hua ZHOU ; Jing TANG ; Qi-Heng TANG ; Li-Ang ZHANG ; Sheng-Jun GUO
Chinese Journal of Surgery 2009;47(3):164-167
OBJECTIVETo investigate the failure mechanisms of revision hip arthroplasties and evaluate the effects of surgical technique, prosthesis design and patient-related risk factors on different failure mechanisms.
METHODSA review of all revision hip arthroplasties from November 1995 to June 2008 identified 30 patients who underwent 30 revisions with 18 males and 12 females. The overall mean age for primary arthroplasties was 49 years (range 25-68 years) and 53 years (range 27-72 years) for index revision arthroplasties and the average interval between these two operations was 43.8 months (0-156 months). The failure mechanisms of index revision arthroplasties and primary arthroplasties were assessed and compared. Direct comparisons were made of data for the different age categories in terms of time to failures and reasons for failures.
RESULTSRegarding revision or prosthesis removal as the end point of the study, the reasons for 30 revision arthroplasties were aseptic loosening in 22 hips (73.3%), infection in 4 hips (13.3%), periprosthetic fracture in 3 hips and instability in 1 hip (3.3%). The overall mean age for last arthroplasties or prosthesis removal was 58 years (range 38-77 years) with an average interval of 78.8 months (range 1-216 months) from previous revision arthroplasties. The mean time to failure for patients above 60 years of age was significantly shorter than patients below 60 years of age (P < 0.01).
CONCLUSIONThe majority of failure mechanisms of revision hip arthroplasties are ineffective fixation of revisional implants and recurrence of local infection, which reveals the limitations to joint reconstruction philosophy and surgical technique.
Adult ; Aged ; Arthroplasty, Replacement, Hip ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Periprosthetic Fractures ; etiology ; Prosthesis Failure ; Reoperation ; Retrospective Studies ; Risk Factors ; Surgical Wound Infection ; etiology ; Treatment Failure
8.Concentration polarization of low density lipoprotein at the distal end of carotid stenosis promotes atherogenesis.
Dang-Heng WEI ; Gui-Xue WANG ; Chao-Jun TANG ; Lin-Qi YE ; Li YANG ; Ling-Hong DENG ; Lu-Shan LIU ; Zuo WANG ; Chao-Ke TANG
Acta Physiologica Sinica 2007;59(6):831-839
To test the hypothesis that concentration polarization of atherogenic lipids may occur in the arterial system and play an important role in localization of atherosclerosis, we simulated and measured in vitro the luminal surface concentration of low density lipoprotein (LDL) in local stenosis at the distal end of carotid artery by number simulation and laser scanning confocal microscopy, then we designed carotid stenosis model to test the role of LDL concentration polarization in atherogenesis. The in vitro experiment showed that the luminal surface LDL concentration was higher than the bulk concentration as predicted by the concentration polarization theory. The relative luminal surface LDL concentration changed with the flow velocity and ratio of stenosis. The wall concentration of LDL was highest in the round tube with 40% stenosis at the same velocity, while the wall concentration of LDL was higher when Re was 250 than Re was 500 at the same extent of narrowness. The animal experiment also revealed that general atherogenic plaques obviously occurred at the distal end of local stenosis where concentration polarized. The results strongly support our hypothesis that concentration polarization of lipoproteins occurs in local stenosis at the distal end of carotid artery, and this in turn promotes the localization of atherosclerosis which develops in the arterial system.
Animals
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Atherosclerosis
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physiopathology
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Carotid Stenosis
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physiopathology
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Disease Models, Animal
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Lipoproteins, LDL
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metabolism
9.An observation of taurine transport alterations in calcification of myocardial cells in vitro.
Yan-rong SHI ; Shu-heng WANG ; Ding-fang BU ; Yong-fen QI ; Lin GAO ; Yong-zheng PANG ; Chao-shu TANG
Acta Academiae Medicinae Sinicae 2002;24(4):359-363
OBJECTIVETo observe the alterations of taurine transport, taurine transporter (TAUT) and cysteine sulfinate decarboxylase (CSD) mRNA in the calcification of myocardial cells in vitro.
METHODS3H-taurine measured the amount of taurine uptake. TAUT and CSD mRNA consents were measured using competitive quantitative RT-PCR in cultured and calcified myocardial cells.
RESULTSIn calcification of myocardial cells, taurine concentration was decreased by 27% (P < 0.05), taurine uptake was markedly reduced, Vmax reduced by 39% (P < 0.01), there were no statistical significance of Km values between the two groups. TAUT mRNA decreased by 45% (P < 0.01), but CSD mRNA increased by 25% (P < 0.05).
CONCLUSIONSThe data suggest that there were impediment of taurine transport in calcification of myocardial cells, as TAUT mRNA level was decreased, but CSD mRNA concentration was improved.
Animals ; Biological Transport ; Calcinosis ; metabolism ; pathology ; Calcium ; metabolism ; Carboxy-Lyases ; metabolism ; Cells, Cultured ; Myocytes, Cardiac ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Rats ; Taurine ; biosynthesis ; genetics ; metabolism
10.Lecithin-cholesterol acyltransferase gene 608C/T polymorphism associated with atherosclerotic cerebral infarction.
Xiao-yan ZHU ; Hong-wei XU ; Rong-yao HOU ; Heng-fang LIU ; Bo XIAO ; Xiao-su YANG ; Qi-dong YANG ; Bei-sha TANG
Chinese Journal of Medical Genetics 2006;23(4):419-422
OBJECTIVETo explore the distribution of lecithin-cholesterol acyltransferase gene (LCAT) 608C/T polymorphism in Chinese Han population and the relationship of the polymorphism association with the occurrence of atherosclerotic cerebral infarction.
METHODSThe lecithin:cholesterol acyltransferase gene 608C/T polymorphism is identified by polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP)and restriction fragment length polymorphism (RFLP) in 150 patients with ACI and 122 healthy controls matching age and sex.
RESULTSThe distribution of LCAT 608C/T gene polymorphism was in accordance with Hardy-Weinberg equilibrium. The CT genotype frequency (14.0%) and T allele frequency (7.0%) in ACI group were significantly higher than those in control group (P<0.05). The concentration of high density lipoprotein cholesterol (HDL-C) in 608CC subgroups were significantly higher than those in 608CT subgroups both in ACI group and in control group (P<0.05).
CONCLUSIONThe LCAT 608C/T polymorphism is possibly a predisposing factor in ACI happening of Chinese Han population. T allele frequency is possibly concerned with the metabolism of HDL-C.
Aged ; Alleles ; Cerebral Infarction ; etiology ; genetics ; Female ; Gene Frequency ; Genotype ; Humans ; Intracranial Arteriosclerosis ; complications ; Male ; Middle Aged ; Phosphatidylcholine-Sterol O-Acyltransferase ; genetics ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Polymorphism, Single Nucleotide ; Polymorphism, Single-Stranded Conformational ; genetics