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Objective:To explore the long-term preservation value and repair effect of normothermic machine perfusion (NMP) on clinically discarded kidneys.Methods:A case of clinical discarded donor kidney was collected, and NMP was carried out in vitro for 9 hours with recovered blood. The dynamic changes of renal appearance, blood gas and biochemistry analysis of perfusate and renal pathology were recorded. Results:In the second to fifth hour of NMP, the appearance of renal was pink and ex vivo normothermic perfusion assessment score (EVNP) was grade Ⅰ. While, the sixth hour and beyond of NMP, the appearance of kidney turned to dark red and EVNP was grade Ⅲ. The renal perfusion blood flow maintained above 150 ml/min in the first 6 hours and decreased significantly after that, and at the end, was only 50 ml/min. During the whole process of perfusion, urine output was maintained at about 100 ml/h. PO 2 remained above 100 mmHg in the first 5 hours of perfusion and from the 6th hour, was lower than 80 mmHg and continued to decline, and was close to 0 at the end of perfusion. The results showed that although the K + concentration changes in blood and urine in the first 5 hours of NMP had a good consistency, the lactic acid level had been rising. In addition, there was no significant change in the histopathology at the fourth hour of perfusion compared with that before zero-point puncture, and the fibrinous thrombus in glomeruli was improved compared with that before perfusion. However, at the sixth hour after perfusion and before the end of perfusion, the pathological changes of renal tissue were significantly worse. There were a large of thrombosis in glomerular blood vessels, renal tubular atrophy and acute tubular necrosis. Conclusions:NMP can realize the evaluation of extended criteria donors before transplantation, and it proves the feasibility and repair potential of NMP in kidney to a certain extent. At the same time, NMP also provides a new way to expand the source of donor kidney and to pre-treat organ in vitro.
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Objective To observe the expression changes of inflammatory cytokines of human tendon-derived stem cells (TDSCs) under uniaxial stretching.Methods TDSCs were isolated from human gracilis tendon by collagenase digestion at very low density.Cells were detected for surface markers by flow cytometry,and tested for multi-differentiation potential in vitro.Repetitive uniaxial stretching was applied on the cells at 0％,4％,8％ or 10％ strain.Under the microscopy,cell alignment was observed after mechanical stretching.Expressions of inflammation factors COX-2 and MMP-1 were detected by qPCR and western blotting.Results TDSCs were successfully isolated from human gracilis tendon.Inflammatory cytokines CD29,CD44 and CD105 were positive,but CD45 and CD14 were negative.TDSCs could differentiate into osteocytes,adipocytes and chondrocytes in vitro.Cells were not realigned4 hours after mechanical stretching.MMP-1 mRNA expression was significantly down-regulated at 4％ strain (0.090 ± 0.007) compared to that at 0％ strain (0.247 ± 0.032,P ＜ 0.05).No significant difference was found in COX-2 mRNA expression at 4％ and 8％ strain (both was 0.005 ±0.001,P ＞0.05).MMP-1 and COX-2 mRNA expressions at 8％ strain (0.168 ± 0.040 and 0.007 ± 0.001)revealed no significant differences from those at 0％ strain (0.134 ±0.075 and 0.006 ±0.003) (P ＞0.05),whereas at 10％ strain MMP-1 and COX-2 mRNA expressions were significantly up-regulated (0.047 ± 0.003 and 0.496 ± 0.036) compared to those at 0％ strain (0.011 ± 0.003 and 0.005 ± 0.003)(P ＜ 0.05).Changes in MMP-1 and COX-2 protein expressions revealed similar trend as their mRNA expressions.In contrast to the setting of 0％ strain,4％ strain induced down-regulated MMP-1 and COX-2 proteins,8％ strain induced no significant changes in MMP-1 and COX-2 proteins,and 10％ strain induced up-regulated COX-2 protein despite minor increase in MMP-1 protein.Conclusions Mechanical stretching can affect the secretion of inflammatory cytokines.Low tensile stretch is associated with decreased expression of inflammatory cytokines while high tensile stretch promotes secretion of inflammatory cytokines.
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Objective To observe the effect of sustained release type Ⅰ collagen-vascular endothelial growth factor (VEGF) on healing of bone-tendon junction injuries.Methods Partial patellectomy was conducted in 72 rabbits divided equally into control group,type Ⅰ collagen group,and collagen type Ⅰ-VEGF group.The scaffold was planted into the bone-tendon interface.Animals were sacrificed at 4,8 and 12 weeks.New bone formation into the patella-patella tendon surface was detected using X-ray films and histological observations.Quality of bone healing was assayed using biomechanical testing.Results At postoperative 4,8 and 12 weeks,X-ray films showed bone formation of type Ⅰ collagen group [(4.1 ± 0.4) mm2,(12.1 ± 0.5) mm2,(13.0 ± 1.2) mm2 respectively] and of collagen type Ⅰ-VEGF group [(3.8 ± 0.4) mm2,(11.0 ± 0.5) mm2,(13.1 ± 1.0) mm2 respectively] were more than that of control group [(2.1 ± 0.6) mm2,(4.1 ± 0.3) mm2,(6.6 ± 0.6) mm2 respectively] (P ＜ 0.05).Histology identified few new bone,massive fibrocyte accumulation and disrupted alignment of tendon fiber in control group,massive new bone formation,neat and orderly alignment of collagen fiber tissues and massive aggrecan expression at postoperative 4 and 8 weeks (fibrous cartage repair in largely) in collagen type Ⅰ-VEGF group,and massive new bone formation but worse alignment of tendon collagen fibers and less aggrecan expression (fibrous repair in largely) in type Ⅰ collagen group.Biomechanical test showed the ultimate tensile strength increased over time in all groups,with significantly higher value at 12 weeks than that at 4 and 8 weeks.At the same time point,ultimate tensile strength ranged in an order as follows:collagen type Ⅰ-VEGF group ＞ collagen type Ⅰ group ＞ control group (P ＜ 0.05).Conclusion Sustained release type Ⅰ collagen-VEGF can accelerate early healing of bone-tendon junction injury and improve the histological and mechanical properties.
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Objective: To develop an indicator system for assessing public hospital performance. Methods:Based on literature research and expert consultation, we formed an indicator system framework and indicators for as-sessing public hospital performance. Using Delphi expert consultation, focus group interviews, focus group discussion and individual in-depth interview qualitative research methods, we constructed a public hospital performance evalua-tion indicators. Results:There are four dimensions, 11 secondary indicators, 30 tertiary indicators in the indicator system, depending on the level of hospital, the indicators and weights are adjusted. Conclusion:The indicator system is suitable for public-interest-oriented performance assessment of public hospitals, and provides basis for the perform-ance assessment system.
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OBJECTIVE@#To investigate the effect of ziprasidone and olanzapine on glucose and lipid metabolism in first-episode schizophrenia.@*METHODS@#A total of 260 schizophrenics were assigned randomly to receive ziprasidone or olanzapine for 6 weeks. The weight was measured at baseline, week 2, 4 and 6. Fasting blood glucose (FBS), fasting insulin, high-density lipoprotein (HDL), total-cholesterol (TC) and triglycerides (TG) were measured at baseline and the end of 6-week treatment. Low-density lipoprotein (LDL) was measured in some patients at baseline and the end of 6-week treatment. Body mass index (BMI) and insulin resistance index (IRI) were counted.@*RESULTS@#A total of 245 patients completed the trial, including 121 ziprasidone patients and 124 olanzapine patients. The average dose was 137.5 mg/d for ziprasidone and 19.5 mg/d for olanzapine. Patients treated with olanzapine had higher weight gain than those treated with ziprasidone [(4.55±3.37) kg vs (-0.83±2.05) kg, P<0.001]. After the treatment, FBS, fasting insulin, HDL, TC, TG, LDL and IRI levels were significantly increased in the olanzapine group (all P values<0.001 ). However, in the ziprasidone group, FBS decreased significantly and HDL and TG levels increased significantly after the 6-week treatment (all P values<0.05). The mean changes of FBS, fasting insulin, TC, TG, LDL and IRI were significantly different in the two groups (all P values<0.001).@*CONCLUSION@#Ziprasidone has less glucose and lipid metabolic effect for first-episode schizophrenia patients in short-term treatment. However, olanzapine induces weight gain and dysfunction of glucose and lipid metabolism significantly, which is associated with increased risk of complications. When the doctors choose antipsychotics in the clinic, they should consider the side effects of the medication.
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Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Benzodiazepines , Therapeutic Uses , Blood Glucose , Lipid Metabolism , Olanzapine , Piperazines , Therapeutic Uses , Schizophrenia , Drug Therapy , Thiazoles , Therapeutic UsesABSTRACT
Neural stem/progenitor cells (NSCs) can spontaneously differentiate into neurons and glial cells in the absence of mitogen fibroblast growth factor-2 (FGF-2) or epidermal growth factor (EGF) in medium and the spontaneous differentiation of NSCs is mediated partially by endogenous ciliary neurotrophic factor (CNTF). This study examined the relationship of FGF-2 and CNTF in the spontaneous differentiation of adult hippocampal progenitor cells (AHPs). AHPs were cultured in the medium containing different concentration of FGF-2 (1-100 ng/mL). Western blotting and immunofluorescence staining were applied to detect the expression of the astrocytic marker GFAP, the neuronal marker Tuj1, the oligodendrocytic marker CNPase and, Nestin, the marker of AHPs. The expression of endogenous CNTF in AHPs at early (passage 4) and late stage (passage 22) was also measured by Western blotting. The results showed that FGF-2 increased the expression of Nestin, dramatically inhibited the expression of GFAP and Tuj1 and slightly suppressed the expression of CNPase. FGF-2 down-regulated the expression of endogenous CNTF in AHPs at both early (passage 4) and late stage (passage 22). These results suggested that FGF-2 could inhibit the spontaneous differentiation of cultured AHPs by negatively regulating the expression of endogenous CNTF in AHPs.
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Neural stem/progenitor cells (NSCs) can spontaneously differentiate into neurons and glial cells in the absence of mitogen fibroblast growth factor-2 (FGF-2) or epidermal growth factor (EGF) in medium and the spontaneous differentiation of NSCs is mediated partially by endogenous ciliary neurotrophic factor (CNTF). This study examined the relationship of FGF-2 and CNTF in the spontaneous differentiation of adult hippocampal progenitor cells (AHPs). AHPs were cultured in the medium containing different concentration of FGF-2 (1-100 ng/mL). Western blotting and immunofluorescence staining were applied to detect the expression of the astrocytic marker GFAP, the neuronal marker Tuj1, the oligodendrocytic marker CNPase and, Nestin, the marker of AHPs. The expression of endogenous CNTF in AHPs at early (passage 4) and late stage (passage 22) was also measured by Western blotting. The results showed that FGF-2 increased the expression of Nestin, dramatically inhibited the expression of GFAP and Tuj1 and slightly suppressed the expression of CNPase. FGF-2 down-regulated the expression of endogenous CNTF in AHPs at both early (passage 4) and late stage (passage 22). These results suggested that FGF-2 could inhibit the spontaneous differentiation of cultured AHPs by negatively regulating the expression of endogenous CNTF in AHPs.
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Animals , Male , Rats , Cell Differentiation , Physiology , Ciliary Neurotrophic Factor , Metabolism , Fibroblast Growth Factor 2 , Metabolism , Hippocampus , Metabolism , Physiology , Rats, Wistar , Stem Cells , Metabolism , PhysiologyABSTRACT
Objective To observe the change and its clinical significance of serum B-type brain natriuretic peptide (BNP) concentration in patients with acute cerebral hemorrhage. Methods The plasma BNP level was measured by microparticle enzyme immunosorbent assay (MEIA) method in 100 patients with acute cerebral hemorrhage. The blood volume of cerebral hemorrhage was computed respectively. The Glasgow Coma Scale (GCS) and National Institutes of Health Stroke Scale (NIHSS) were used to evaluate nerve function on the 1st, 3rd, 7th and 15th day after admission, and the Glasgow Out-come Scale (GOS) was used when the patient was discharged from hospital or died. Results The plasma BNP level at the 2nd day after admission was positively correlated with the blood volume of cerebral hemorrhage in patients with acute cerebral hemorrhage (r=0.367, P=0.000), with NIHSS score at the 1st, 3rd, 7th and 15th after admission (r=0.491, 0.444, 0.427 and 0.458, all P=0.000), and with GOS score (r=0.507, P=0.000). In addition, it was negatively correlated with GCS score at the 1st, 3rd, 7th and 15th after admission (r=-0.553, -0.429, -0.473 and -0.501, all P=0.000). Conclusions The plasma level of BNP is good for predicting the strike of cerebral hemorrhage patient′s condition, it is likely to provide a original thread for judge the severe degree of patient′s condition.
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Objective To examine the reliability,validity and sensitivity of Montgomery-Asberg Depression Rating Scale (MADRS) for patients with current major depression disorder (MDD). Methods One hundred and twenty-two current MDD (DSM-Ⅳ) patients were administered with MADRS, Hamilton Rating Scale for Depression-17 item version (HAMD) and Clinical Global Impression of Severity (CGI-S) at baseline, 12 patients were selected to complete rater agreement test,and 47 patients receiving antidepressant treatment were followed up at 2,4,6 and 8 week and administered with MADRS and HAMD. Correlation analysis, reliability analysis and effect size (ES) calculation were used to determine the reliability,validity and sensitivity to changes during drug treatment. Results Intra rater reliability for MADRS was 0. 954. Baseline item-total score correlations were between 0. 445 and 0. 770 (P ＜ 0. 01 ), and the average correlation was 0. 629. The Cronbach α coefficient was 0. 847. The criterion related validity with HAMD and CGI-S was 0. 853 and 0. 672 (P＜0.01) ,respectively. The re-test reliability for MADRS at 2,4,6 and 8 week was 0. 737 ,0. 651,0. 543 and 0. 524 (P＜0. 01 ) ,respectively.MADRS had higher ES than HAMD when taken as clinical endpoint outcome measurement (0.41 vs 0.40,0.87 vs 0. 72,1.14 vs 0. 88,1.20 vs 0. 96 for 2nd,4th,6th and 8th week, respectively). Conclusion MADRS has good reliability and validity for patients with MDD. It is more sensitive to assess drug effect than HAMD.
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ObjectiveTo establish rabbit knee joint cartilage injury models to evaluate effects of the type Ⅱ collagen sponge in repair of the articular cartilage.MethodsThe type Ⅱ collagen sponge was prepared according to previous method and the pore size of the sponges was measured based on the collagen autofluorescence characteristics.The type Ⅱ collagen sponge was transplanted into the injury lesions of the animal model for experimental study.The regeneration of the cartilage defects was observed by using MRI, histologic HE staining, Safranin O, sirius red polarized light staining, areas determination of the newly grown cartilage and immunohistochemistry of type Ⅱ collagen.ResultsAutofluorescent images of confocal microscope layer scanning showed that the pore size was (93.26 + 38.40) μm in diameter, suitable for chondrocyte growth.Comparison between MRI and H&E staining results showed quicker effusion absorption in the treatment groups than that in the control group, while the level of inflammatory response in the treatment group was lower than that in the control group.The sporadic cartilage signals first appeared at the 6th week.The newly formed cartilage with the expression of glycosaminoglycan and type Ⅱ collagen matrix was confirmed by Safranin O staining and immunohistochemical analysis.The sirius red polarized light staining showed that areas of the newly formed cartilage were significantly larger in the treatment group than that in the control group (P ＜ 0.01).Conclusion The type Ⅱ collagen sponge developed from purification can effectively repair the damaged cartilage tissues of the rabbit knee joints, as has been verified either by MRI or histology.
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Objective To observe the effect on succinate dehydrogenase (SDH) of mitochondria in myocardium and liver in sepsis rats treated with edaravone. Methods 30 Sprague-Dawley rats were divided into 3 groups: sham operated group ( group A ), controlled operated group ( group B ), treated group with edaravone (group C). The model of sepsis rats was made by the way of caecum ligated and punctured and 20mg/kg lactate levofloxacin was subcutaneously injected (sci) 15min before and 3h after operation in three group. 5mg/kg edaravone were sci 15min before and 3h after operation in group C. Liver and myocardium were taken from all of them 18h after operation. The activities of SDH in myocardial and hepatic mitochondria were detected, pathological change of mitochondria in liver and myocardium were observed. Results The activities of SDH in myocardial and hepatic mitochondria in group B [ (0. 21 ± 0. 07 ) U/mgprot, (0. 23± 0. 08 ) U/mgprot ] were significantly decreased compared with group A [ ( 0. 33 ± 0. 10 ) U/mgprot, ( 0. 38±0. 12)U/mgprot]. The activities of those in group C[ (0.31 ±0. 08) U/mgprot, (0. 36 ±0. 11)U/mgprot] were significantly increased than group B. Myocardial and hepatic mitochondria swelling and endocytoplasmic reticulum expanding were found in group B by electron microscope, while it showed normal in group C. Conclusion Hepatic and myocardial mitochondrial structure were destroyed and activities of SDH were decreased in sepsis rats. They could be effectively protected by edaravone.
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OBJECTIVE@#To compare the effect of 7 antipsychotic drugs on the life quality of schizophrenia patients including chlorpromazine, sulpiride, clozapine, risperidone, olanzapine, quetiapine, and aripiprazole.@*METHODS@#A total of 1,227 stable schizophrenic patients within 5 years onset who took 1 of the 7 study medications as maintenance treatment were followed up for 1 year at 10 China sites. Patients were evaluated by the short form-36 health survey (SF-36) at the baseline and at the end of 1 year.@*RESULTS@#The life quality was improved obviously at the end of the follow-up. There was significant difference in body pain, vitality, and mental health (P<0.05) among these antipsychotic drugs.@*CONCLUSION@#All 7 antipsychotic drugs can improve the life quality of schizophrenia patients. Atypical antipsychotic drugs, especially olazapine and quetiapine, are superior to typical antipsychotic drugs in improving life quality.
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Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Antipsychotic Agents , Therapeutic Uses , Benzodiazepines , Therapeutic Uses , Dibenzothiazepines , Therapeutic Uses , Follow-Up Studies , Olanzapine , Quality of Life , Quetiapine Fumarate , Schizophrenia , Drug Therapy , Surveys and QuestionnairesABSTRACT
BACKGROUND: Polyvinyl alcohol (PVA) displays limitation to cell adsorbability. Can collagen improve the adsorbability of PVA to cells?OBJECTIVE: To develop a novel type composite of PVA and collagen, and explore the feasibility to serve as soft tissue substitute.DESIGN: Single sample observation.SETTING: Guangzhou Red Cross Hospital, Jinan University Medical College, Guangzhou Institute of Traumatic Surgery.MATERIALS: Fifteen New Zealand rabbits of 2.0-3.0 kg, either male or female, were provided by Medical Experimental Animal Center of Guangdong Province. The experiment was carried out in the Laboratory of Guangzhou Institute of Traumatic Surgery, and the experimental procedure was accorded with the animal ethical standards. Bovine typeI collagen was purchased from Guangzhou Trauer Biotechnology Co., Ltd. and PVA-124 from Guangzhou Chemical Reagent and Instrumentation Co., Ltd.METHODS: The experiment was performed in Guangzhou Red Cross Hospital, Jinan University Medical College between July 2003 and December 2006. ①Preparation of PVA-collagen material: 5 g/L bovine type I collagen was mixed with 5% PVA-124 at a ratio of 1 : 1. The mixture was freeze-dried at vacuum until becoming gelatinous. The internal structure was observed under the use of scanning electron microscope. ②Cytotoxicity test: PVA-collagen composite was cut into pieces of 10 mm×5 mm× 1 mm, put into 48-well culture plate after sterilized by Y ray, cultured with 1×104 3T3 cells in each well. Cell growth was observed under scanning electron microscope and laser scanning confocal microscope. ③Embedding test in vivo: Two longitudinal incisions were cut at the two sides of spine. The subcutaneous tissue was separated bluntly to form subcutaneous lacuna. Four pieces of PVA-collagen material were implanted in the lacuna and fixed. Nine specimens and the surrounding tissues were harvested from three rabbits each at one, four, eight and sixteen weeks postoperatively for pathological observation.MAIN OUTCOME MEASURES: The internal structure of gel film under scanning electron microscope, cytotoxicity test and embedding test in vivo results.RESULTS: ①Internal structure of PVA-collagen material:PVA-collagen material showed white gel shape after freeze-drying at vacuum. Penetrating three-dimensional pores were observed in the surface and inner section under scanning electron microscope. ②Cytotoxicity test results showed that 3T3 cells grew normally on the PVA-collagen material. ? Embedding test in vivo results suggested that one week after PVA-collagen implantation, foreign body reaction occurred, and the interface between material and tissue was clear. Four weeks later, only rare lymphocyte infiltration was observed, and a great amount of fibroblast hyperplasia formed collagen fibrils and false simple cuboidal epithelium coating material. In 8 weeks, no lymphocyte infiltration, neutrophilic granulocyte infiltration or foreign body giant cell were found; dense capsule wall and capsule coating material generated from a great amount of fibroblasts were observed. In 16 weeks, extending collagen fibrils were found arranged regularly with shrank nucleus, showing long ovoid or long fusiform in shape; no new formation small vessels, lymphocyte, neutrophilic granulocyte infiltration or foreign body giant cell infiltration were observed. The capsule wall was stable and thinned. CONCLUSION: PVA-collagen composite has good cell compatibility and tissue compatibility but no toxic or adverse effect. It can serve as in vivo implant.
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This study sought to explore a new compound polyvinyl alcohol-collagen as a wound dressing. To make the polymer, Polyvinyl alcohol (PVA) and collagen type I were put together in the ratio of 3:1, at the same time, polyethlene glycol as porogen was added, and the material was dried by air to be a membrane in shape. Then the ultimate tensile load, the hole diameter, porosity, and water absorption were measured. The cell biocompatibility was tested as well. The results showed the PVA-collagen blend had the average hole 100-150 microm in diameter, and the porosity about 90%. The ultimate tensile load reached 8.10 +/- 0.28 MPa, and water absorption was up to 185.42% +/- 6.93%. 3T3 cells grew well on the PVA-collagen member. Therefore, the PVA-collagen memberane is characterized not only by its ideal biomechanical ability and biocompability, but also by its ideal hole diameter, porosity and water absorption. It may have the potential for use as a wound dressing in vivo.
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Humans , Biocompatible Materials , Chemistry , Collagen , Chemistry , Occlusive Dressings , Polyvinyl Alcohol , ChemistryABSTRACT
Objective To investigate the effects of B.adolescentis and L.acidophilus in treatment of dextran sulphate sodium (DSS)-induced ulcerative colitis(UC) in mice and their potential mechanisms. Methods Seventy-five BABL/C mice were randomly divided into control,saline (NS),B.adolescentis BF0624 treatment (B),L.acidophilus LT0637 treatment (L) and salicylazosulpha-pyridine treatment (S) groups.Except control group,the other four groups were received DSS to induce ulcerative colitis. The weight-loss,fecal trait and bleeding were recorded every day.Colonic length and histological scores were evaluated on day 3,5 and 7.The gene and protein expression of hot shock protein (HSP)70, glucocorticoid receptor (GR),interleukin (IL)-10 and tumor necrosis factor (TNF)-α were detected by Western blot and reverse polymerase chain reaction (RT-PCR) respectively.Results B.adolescentis BF0624 and L.acidophilus LT0637 could relieve the inflammatory reaction of the experimental UC.The DAI scores were 1.84±0.4 in L group on day 3,which was lower than that in NS group (2.8±1.0).The DAI scores in all treatment groups were decreased on day 5.Compared with NS group[(8.1±0.6)cm ], the colon length on day 8 were (9.0±0.6)cm in B group,(9.35±0.6)era in L group and (8.8±1.1)cm in S group (P＜0.05).The colonic mucosa was improved pathohistologically in L group (6.0±1.0) on day 8.The expression of HSP70 and IL-10 in B and L groups were up-regulated and the expression of TNF-α was down-regulated.Conclusions Both B.adolescentis BF0624 and L.acidophilus LT0637 were effective in treatment of acute ulcerative colitis.The potential mechanism of two probiotics may be related with up-regulation of HSPT0 and IL-10 expressions and down-regulation of TNF-α expression.
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To detect the cellular immunity state of New Zealand white rabbit immunized by pig type II collagen. The New Zealand white rabbit was immunized by type II collagen for sixty days. The plasma was collected at a regular interval and the anti-type II collagen antibodies were examined. At the sixtieth day, the peripheral circular lymphocytes and the lymphocytes separated from spleen cells of rabbit and lymph nodes were collected and were stimulated by type II collagen in vivo again. The regulation of reactive cellular proliferation caused by the stimulation was detected. The experiment samples were divided into two groups. The first group was the positive control group by adding different concentrations of PHA and the non-specific immunity was assayed. The different concentrations of type II collagen were added to the second group and the specific immunity was assayed. The lymphocytes of normal rabbits showed proliferation by PHA stimulation but no proliferation by the first stimulation of type II collagen. Obvious proliferation due to the stimulation of both PHA and type II collagen in the immunized rabbit were observed. It shows that certain concentration of heterogeneous collagen may cause an increase of anti-type II collagen antibody in immunized rabbit and may cause a proliferation of lymphocytes in rabbit spleen and peripheral blood. The heterogeneous type II collagen causes cellular immunity in vivo.
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Animals , Female , Male , Rabbits , Cell Division , Collagen Type II , Allergy and Immunology , Cytotoxicity, Immunologic , Histocompatibility Antigens , Lymphocytes , Cell Biology , Allergy and Immunology , Spleen , Cell Biology , Swine , Transplantation, HeterologousABSTRACT
[Objective]Porous collagen type Ⅱ matrices crosslinked by 1-ethyl-3-(3-dimethyl aminopropyl)carbodⅡmide(EDC) and N-hydroxysucinimide(NHS) were developed as scaffolds for cartilage tissue engineering.[Method]Collagen type Ⅱ matrix was crosslinked by EDC/NHS,and then freeze-dried to achieve collagen scaffolds.The porous characteristics of the prepared scaffolds were tested by using diffenent methods,including laser scanning confocal microscopy (LSCM),scanning electron microscopy (SEM) and mechanical testing machine.The chondrocytes labeled by GFP were planted in crosslinked collagen type Ⅱ,and observed by LSCM.[Result](1) The mechanical properties of cross-linked matrices increased significantly,reaching 2.18?0.47MPa.(2)The degradation of cross-linked matrices decreased by 8.28% after 4 hours.The pore size was about 90?m,and their average porosity and water capacity reached 93.39% and 97.78%,respectively.3.Chondrocytes were in good condition in the crosslinked collagen.[Conclusion]The present work indicates that EDC/NHS-crosslinked collagen type Ⅱ could keep the properties and biocompatibility of collagen,besides,the mechanical strength increased and the degradation was decreased.It will be suitable for cartilage tissue engineering purposes.
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Recently,tissue-engineered chondrocyte transplantation has been tried to treat full-thickness cartilage defects.Of the many scaffold materials being investigated,collagen,with good biocompatibility,biodegradable and biological activity,has been shown to have many advantageous features for the proliferation,the attachment and the differentiation.The present article reviews the applications and prospects of collagen in cartilage tissue engineering.
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Embryonic stem cell possess multi-directional differentiation capacity and can differentiate into all sorts of cells of three germ layers,it has the widely use in the treatment of tissue repair.Recent study shows that,embryonic stem cells can differentiate into cartilage cells in the effect of cytokines,hormones,micro-environment etc.In the is review,the author explore several studies and review the effects of different factors to the differentiation of embryonic stem cell to chondrocyte.
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[Objective]To investigate the feasibility of the fabrication of tissue-engineered anterior cruciate ligament(ACL)in vitro by studying biocompatibility and mechanical property of the braided polyvinyl alcohol(PVA)materials.[Method]Firstly,human ACL cells and NIH3T3 cells were isolated,expanded in vitro and seeded onto the surface of the braided PVA scaffold materials,the adhesion,proliferation and three-dimensional growth of cells on the scaffold were observed by SEM.Secondly,the biomechanical properties of the braided PVA scaffold materials were measured with electro-biomechanical machine.[Result]The braided PVA scaffold materials had no cytotoxicity,ACL and NIH3T3 cells adhered,grew and proliferated well both on the surface and in the holes of the braided PVA scaffold materials.The maximum load,the maximum strain and ultimate tensile stress of the braided PVA scaffold materials respectively were 169.78?9.18N,11.67?1.38% and 52.21?2.88MPa.[Conclusion]The braided PVA scaffold materials possess good biomechanical properties and biocompatibility,it may become an ideal biomaterial for fabricating tissue-engineering ACL if the biomechanical properties can be improved.