1.Drug release, morphology and cytotoxicity of enantiomeric poly(L-Lactic acid)-poly(ethylene glycol)-poly(L-Lactic acid)/poly(D-Lactic acid)-poly(ethylene glycol)- poly(D-Lactic acid) stereocomplex hydrogel
Zhili TIAN ; Yao WU ; Rong LIU ; Yanfeng XIAO ; Bin HE ; Zhongwei GU ; Fang WU
Chinese Journal of Tissue Engineering Research 2011;15(29):5501-5506
BACKGROUND: Recently biodegradable hydrogel has been extensively used to delivery anticancer drug and bioactive macromolecule. However, to protect the activity of the bioactive macromolecule, we need to obtain series of hydrogel which have milder hydrogelation conditions and shorter hydroglation time.OBJECTIVE: To prepare enantiomeric poly(L-Lactic acid) (PLLA)-poly(ethylene glycol (PEG)-PLLA/ poly(D-Lactic acid) (PDLA)-PEG-PDLA stereocomplex hydrogel which has shorter hydroglation time, to physically encapsulate a model drug-lysozyme and sustained release it from the hydrogel. METHODS: Triblock copolymers of PLLA-PEG-PLLA and PDLA-PEG-PDLA were synthesized by ring-opening polymerization of L(D)-lactide using PEG as the initiator and Sn(Oct)2 as the catalyst. The triblock copolymers were characterized by 1H nuclear magnetic resonance, FT-IR and X-Ray diffractometry. A hydrogel was prepared from an aqueous mixture of PLLA20-PEG227-PLLA20 and PDLA21-PEG227-PDLA21 (10 wt% concentration) at room temperature for 12 hours. X-Ray diffractometry test was used to research the gelation mechanism. The release profile of the lysozyme as a model drug from the hydrogel was tested. The morphology of the freeze-dried hydrogel was investigated by scanning electron microscope. The cytotoxicity of the hydrogel was evaluated by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide) assay.RESULTS AND CONCLUSION: Triblock copolymers of PLLA-PEG-PLLA and PDLA-PEG-PDLA were obtained. Both the PEG and PLA blocks in the copolymers could crystallize, but the crystallization of the PEG block was predominant. The stereocomplex formation between the PLLA and PDLA blocks within the hydrogel was confirmed by the X-Ray diffractometry analysis. The release profile of the lysozyme from the hydrogel exhibited a sustained-release pattern with a duration period of 7 days. The hydrogel exhibited a 3D interconnected porous structure with 50-100 μm pore size after being freeze-dried. The mouse fibroblast cell viability percentage was 99.3% after the cells contacted with the 100% extracted liquid for 72 hours.
2.The effects and mechanisms of BTBD10 on the proliferation of islet beta cell
Yu LIU ; Zhaoyan GU ; Xinyu MIAO ; Yahping GONG ; Yujun XIAO ; Jian LI ; Hui TIAN ; Chunlin LI
Chinese Journal of Internal Medicine 2012;51(2):136-139
ObjectiveTo explore the role of BTBD10 overexpression in the proliferation of insulinoma cell line INS-1and its mechanism. MethodsThe recombined expression plasmid of pcDNA4.0-BTBD10 was constructed by gene cloning technique and was transfected into INS-1 cell by lipofectamine 2000. The stable overexpression BTBD10 of INS-1cell was selected at 48th hour after transfection.INS-1 cell proliferation activity was measured by MTT method.The expression of BTBD10,protein kinase B(Akt),phospho-Akt(p-Akt),mammal target of rapamycin (mTOR) and phospho-mTOR (p-mTOR) were determined by Western blot.ResultsThe stable overexpression BTBD10 of INS-1 cell wassuccessfullyconstructed.OverproductionofBTBD10promotedbetacellproliferation.The phosphorylation of Akt and mTOR was increased and the ratio of p-Akt/Akt and p-mTOR/mTOR was enhanced in the INS-1 overexpressed by BTBD10.But the expression of total Akt and mTOR presented no obvious changes. Conclusion The overexpression BTBD10 of INS-1 cell could activate of Akt/mTOR signalling pathway via stimulating phospho-mTOR and Akt,and enhance overall cell protein translation,so as to promote proliferation of INS-1 cell.
3.Inhibitory effect of RNA interference on the expression of interleukin-6 receptor in the acute phase of spinal cord injury
Mingyong GAO ; Jiande XIAO ; Zhenyu LI ; Hongyin YAN ; Zheng YU ; Changqing TIAN ; Yang CHEN ; Hongsheng GU
Chinese Journal of Tissue Engineering Research 2007;11(32):6497-6501
BACKGROUND: Pathophysiological mechanism of local microenvironment is complex after central nerve injury; especially,both inflammatory reaction at an acute phase and formation of secondary glial scar have tremendous effects on effective regeneration of axon, regeneration and arrangement of local nerve cells, proliferation and migration of local stem cells;therefore, it becomes a basic reason for blocking nerve repair in an early period. Thus, how to effectively resist inflammatory factors in injured region at an acute phase and how to optimize microenvironment of neural regeneration are the most important strategies for repairing spinal cord injury in recent years.OBJECTIVE: To design, establish and screen the best expression of interleukin-6 receptor (IL-6R) α to inhibit shRNA adenovirus expression vector by using spinal cord injury models.DESIGN: Duplicative measurement study.SETTING: Department of Spine Surgery, the Second People's Hospital of Shenzhen.MATERIALS: A total of 40 healthy Wistar rats, either gender, 8-10 weeks old, were selected in this study. Rabbit-anti-rat glial fibrillary acidic protein (GFAP) antibody Ⅰ was provided by Santa Cruz Compan; siRNA eukaryon expression plasmid pGenesil (cohtaining green fluorescent expression system) was provided by Wuhan Jingsai Bioengineering Company.METHODS: The experiment was carried out in ImmuneOpening Laboratory, Basic Medical Faulty, Tongji Medical College, Huazhong University of Science and Technology, and Medica Laboratory Center, the Second People's Hospital of Shenzhen in November 2006. Three pairs of shRNA template which composed of 19 bp reverse repeated motif of IL-6 receptor (IL-6R) α target sequence with 9 bp spacer were designed and synthesized, then the recombinant adenovirus expression vectors with green fluorescence protein were constructed in vitro respectively. The acute spinal cord injury models were completed, and the adenovirus recombinants were regionally injected post 12 hours after spinal cord injury;in addition, the inhibitory effect of RNA interference (RNAi) on expression of IL-6R in local region after spinal cord injury were detected by using real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot so as to screen adenovirus expression vector which had the best inhibitory effect on expression of IL-6R.MAIN OUTCOME MEASURES: Inhibitory effect of RNAi on expressions of IL-6R RNA and protein in local region after spinal cord injury.RESULTS: Sequence analysis showed that IL-6R-shRNA recombinant adenovirus expression vector was successfully constructed, and optimal IL-6R-shRNA recombinant adenovirus expression vector was screened by using real-time fluorescence quantitative RT-PCR and Western blot. The IL-6R expressions were 49% and 56% at the levels of mRNA and protein, respectively.CONCLUSION: The IL-6R--shRNA recombinant adenovirus expression vector is successfully constructed and screened.The gene expression of IL-6R can be highly inhibited after acute spinal cord injury.
4.Breast fibroadenoma:comparative study of pathological features with varied MRI findings
Xiao-Hong WANG ; Wei-Jun PENG ; Wen-Tao YANG ; Ya-Jia GU ; Tian-Xi YANG ;
Chinese Journal of Radiology 2001;0(05):-
Objective To identify histopathologic correlates for the various MRI appearances of breast fibroadenomas.Methods Thirty-eight fibroadenomas in 33 patients(aged 24—57 years)examined with gadolonium-enhanced MR imaging were observed for signal intensity on T_2-weighted images,contrast enhancement,shape,and internal septation,and these findings were correlated with histopathologic findings.All cases underwent surgery and were proved by pathology.Results(1)The lesion shape was lobular,or round in 34 of 38 fibroadenomas(89.5%).(2)The signal intensity on T_1-weighted images was less than or equal to that of fibroglandular tissue in all cases.The signal intensity on T_2-weighted images was highly varible:high T_2 signal intensity was associated with more myxomatous stromal(mean myxoid-sclerotic index value of 1.9),higher stromal cellularity(mean stromal cellularity index value of 2.2); Fibroadenomas with low T_2 signal intensity had stromal that was nearly uniformly sclerotic(mean myxoid- sclerotic index values of 2.8)and low stromal cellularity(mean stromal-cellularity index value of 1.2). Significant differences were found between these two groups,x~2=11.267 and x~2=10.415(P0.05).The degree of contrast enhancement was proved to be related to ages of patients.The enhancement was more intensely in younger patients.(5)Internal septations were identified within nine of 33 enhancing fibroadenomas (27.3%)and appeared to correlated with collagenous bands at histopatholigic analysis.Conclusions Fibroadenomas demonstrate marked histopathologic variability.The resultant variability in the MR appearance correlated with the degree of myxomatous or sclerotic and stromal cellularity.Lobulation and internal septation,which appear to reflect intrinsic growth patterns of fibroadenomas,may provide more reliable information for distinction.Familiarity with the diagnostic features would facilitate to make the differential diagnosis correctly.
5.Clinical application of percutaneous vertebroplasty in treating osteoblastic spinal metastases
Qinghua TIAN ; Chungen WU ; Yifeng GU ; Tao WANG ; Yv HE ; Hongmei SONG ; Fei YI ; Chengjian HE ; Quanping XIAO ; Yongde CHENG
Journal of Interventional Radiology 2014;(5):411-414
Objective To discuss the feasibility and short-term clinical effectiveness of DSA-guided percutaneous vertebroplasty (PVP) for the treatment of painful osteoblastic metastatic spinal lesions. Methods During the period from Jan. 2010 to Dec. 2011 at authors’ hospital PVP was carried out in 23 patients with osteoblastic spinal metastases (34 lesions in total). Coexisting osteoblastic pathological fracture was found in twelve patients. The WHO standards, visual analogue scale (VAS) and karnofsky-KPS score were used to evaluate the therapeutic results. Results Technical success was achieved in all patients. All patients were followed up for at least 3 months. Of 20 patients who had complete clinical data, complete remission (CR) was obtained in 6, partial remission (PR) in 10, mild remission (MR) in 3 and no remission (NR) in one. The clinical effectiveness (CR+PR) was 80%. The mean VAS scores dropped from preoperative (7.0 ± 1.6) to (2.2 ± 1.9) at 24 hours after the treatment, and to (2.4 ± 2.1) and (2.5 ± 2.1) at one and three months after the treatment respectively. The mean KPS scores rose from preoperative (76.5 ± 10.4) to (86.5 ± 11.8), (88.0 ± 12.0) and (89.0 ± 10.8) at 24 hours and one, three months after the treatment respectively. Small amount leakage of PMMA was observed in 4 cases (17.4%) with no obvious clinical symptoms. Conclusion DSA-guided PVP is a feasible and effective treatment for painful osteoblastic spinal metastases. This therapy can immediately relieve pain and reinforce spine, besides, it can remarkably improve the living quality and
decrease the incidence of paraplegia.
6.Metabolic Characteristics of Insulin Secretion and Insulin Sensitivity in Isolated Postchallenge Hyperglycemia
jing-yan, TIAN ; yan-yun, GU ; xian-ling, ZHANG ; hong, LI ; wei-bin, ZHOU ; hong-li, ZHANG ; xiao, WANG ; tian-hong, LUO ; guo, LI ; min, LUO
Journal of Shanghai Jiaotong University(Medical Science) 2006;0(09):-
Objective To evaluate the metabolic characteristics of insulin secretion and insulin sensitivity in isolated postchallenge hyperglycemia(IPH) and to clarify the factors responsible for the development of IPH. Methods(Eight hundred) and fifty subjects were classified into the following three groups based on the results of a 75-g oral glucose tolerance test(OGTT): normal glucose tolerance(NGT),n=557;isolated impaired glucose tolerance(iIGT),n=146;and IPH,n=147.Insulin secretion(insulinogenic index) and insulin sensitivity(insulin sensitivity index) were identified in the three groups. Results From NGT to iIGT and IPH in these subjects,the insulinogenic index and insulin sensitivity index were gradually decreased(P
7.Effect of Amylin on Secretion of Insulin and Glucagon in Rats
jing-yan, TIAN ; hong-li, ZHANG ; yang-yun, GU ; feng-ying, LI ; jia, XU ; xiao, WANG ; tian-hong, LUO ; guo, LI ; min, LUO
Journal of Shanghai Jiaotong University(Medical Science) 2006;0(08):-
Objective To study the effect of amylin on the secretion of glucagon and insulin in isolated rat islets. Methods The models of isolated rat islets were established by collagenase digestion and dextran gradient centrifugation. The influence of various concentrations of amylin on both glucagon and insulin secretion was studied. Results Various concentrations of glucose increased the insulin secretion and decreased the glucagon secretion.Compared with the control, islets exposed to amylin (10~ -10 to 10~ -5 mol/L) for 1 hour showed decreasing glucagon secretion as the glucose increased (0, 5.6 and 11.2 mmol/L) (P
8.Psychological trauma of funnel chest in adolescents and the appropriate age for minimally invasive surgery repair.
Jing ZHAO ; Li LUO ; Li-jun XIAO ; Ling-yun GU ; Tian-sheng SUN
Chinese Medical Journal 2013;126(15):2876-2880
BACKGROUNDFunnel chest has a negative effect on adolescents and it has a strong effect on adolescents' psychological and behavior. This study aimed to investigate the psychological characteristics and factors that affect adolescents with funnel chest and to evaluate the relationship between the patients' age and their physiological and psychological health. We aimed to establish an age model for maximum surgery benefits for funnel chest patients to provide an objective basis for choosing surgery.
METHODSThe study adopted a general evaluation approach to assess the risk and benefits of minimally invasive surgery for funnel chest. The funnel chest index, the Symptom Checklist-90, and the Eysenck Personality Questionnaire were used as assessment tools to observe physiological and psychological features in funnel chest patients. A sample of 234 adolescents with funnel chest was selected from a third-grade class-A hospital in Beijing. Age groups were adopted as an independent variable, and other factors in funnel chest patients were dependent variables.
RESULTSThere was a significant difference in the relapse rate for funnel chest in the different age groups (χ(2) = 11.883, P = 0.008). There was a higher relapse rate in patients of ≤10 or ≥19 years old than in patients of 11-18 years old. There was a significant difference in the SCL-90 total score in the different age groups (F = 12.538, P = 0.0001), the patients older than 13 years had a higher score than those younger than 13 years in the SCL-90. There was a significant difference in the standard score of E (introversion/ extraversion) in the different age groups (F = 10.06, P = 0.0001). There was also a significance in the funnel chest index before surgery in the different psychological scales (P < 0.01), with a higher funnel chest index score associated with more obvious psychological trauma. Age and the number of variables, including the relapse rate, SCL-90 score, standard score of E, and standard score of N in the EPQ were significantly correlated (correlation indices were 0.402, 0.623, -0.505, and 0.473, respectively, P < 0.01).
CONCLUSIONSThere are higher complication rates after surgery and relapse rates when funnel chest patients are too young or too old. There is more obvious psychological trauma in patients with a high funnel chest index. Our results indicate that the best age for surgery for funnel chest is 14-16 years.
Adolescent ; Adult ; Age Factors ; Child ; Funnel Chest ; psychology ; surgery ; Humans ; Minimally Invasive Surgical Procedures ; Psychological Tests ; Psychology, Adolescent
9.Expression of human tumstatin in Pichia pastoris and its bioactivity.
Qu-Liang GU ; Tian-Yuan ZHANG ; Jin-Xian LUO ; Jing-Jing GAN ; Fan XIAO
Chinese Journal of Biotechnology 2006;22(3):451-456
Human tumstatin(hTumstatin)cDNA was amplified from recombinant plasmid pET-3c-tum, cloned in frame with the signal sequence in yeast vector pPICZalphaA and transformed into Pichia pastoris GS115 by electroporation. The expression of hTumstatin in GS115(pPICZalpha-tum)was then induced by methanol and secreted into the culture medium, with a yield of 25mg/L as shown by SDS-PAGE and Western blotting. The expressed hTumstatin was purified to more than 85% purity using a simple one-step SP-Sepharose cation exchange chromatography. The MTT and chick chorioallantoic membrane assay showed that the yeast produced hTumstatin could inhibit the proliferation of human umbilical vein endothelial cells and the neovascularization induced by bFGF. Hoechst 33258 fluorescent staining also demonstrated the apoptotic change in endothelial cellular nuclear morphology.
Angiogenesis Inhibitors
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metabolism
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Autoantigens
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genetics
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metabolism
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Cell Proliferation
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Cells, Cultured
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Collagen Type IV
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genetics
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metabolism
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DNA, Complementary
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genetics
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Electroporation
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Endothelial Cells
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cytology
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Humans
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Pichia
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genetics
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metabolism
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Recombinant Proteins
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genetics
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metabolism
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Umbilical Cord
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cytology
10.Effect of inducible nitric oxide synthase on intestinal microcirculation in endotoxic shock.
En-Yi SHI ; Xiao-Jing JIANG ; Han BAI ; Tian-Xiang GU ; Nakajima YOSHIKI
Acta Physiologica Sinica 2005;57(1):39-44
To investigate the changes of intestinal microcirculation in endotoxic shock and the effect of inducible nitric oxide synthase (iNOS) on intestinal microcirculation, endotoxic shock was induced by intravenous injection of lipopolysaccharide (LPS) in mice. Mean arterial pressure (MAP) was monitored throughout the experimental procedure. The velocity and flux of red blood cell (RBC) in villus tip arteriole and capillaries were measured by FITC-labeled erythrocytes and intravital microscopy. The effect of iNOS was determined by targeted disruption of mice iNOS-gene and administration of S-methylthiourea sulfate (SMT), a selective inhibitor of iNOS, before LPS injection. No significant differences in MAP, RBC velocity and flux at baseline were found among wild type mice, SMT pretreated mice and iNOS-gene knockout mice. LPS induced a dramatic fall of MAP in wild type mice. The decrease of MAP was significantly restored in iNOS-gene knockout mice and in wild type mice received SMT before LPS injection. The velocity and flux of RBC in villus tip arteriole and capillaries decreased markedly after LPS injection in wild type mice, while significantly higher velocity and flux of RBC were found in iNOS-gene knockout mice and SMT-pretreated mice both 60 and 120 min after LPS injection. The results demonstrate that iNOS plays an essential role in the intestinal microcirculation disturbance which occurs in endotoxic shock.
Animals
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Intestines
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blood supply
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Lipopolysaccharides
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Male
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Mice
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Mice, Knockout
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Microcirculation
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physiology
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Nitric Oxide Synthase Type II
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genetics
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physiology
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Shock, Septic
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chemically induced
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physiopathology