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Objective:To explore the effect of estrogen-related receptor α (ERRα) on lipopolysaccharide (LPS)-induced vascular endothelial cell apoptosis and tight junction protein degradation.Methods:RPMVECs transfected with shERRα were cultured in vitro and divided into four groups: Normal control group (Ctr group); shERRα knockdown group (shERRα group); normal cells + LPS treated group (LPS group): The cells in the six-well plates were cultured in serum-free medium for 12 h, and then treated with 20 μg/mL LPS for 12 h; and shERRα+LPS group: ERRα knockdown cells were treated as the LPS group. ROS fluorescence kit was used to detect the intracellular ROS levels . Apoptosis ratio was detected by TUNEL staining, AnnexinV-FITC and PI. Cell membrane ZO-1 expression was detected by cellular immunofluorescence, and the levels of apoptosis-related proteins Bcl-2, Bax, Smac, Cytochrome c, and tight junction protein ZO-1, as well as the expression of Occludin, JAM-A and E-Ca at molecular level were detected by Western blot.Results:Compared with the Ctr group and the shERRα group, the ROS level, apoptosis rate (TUNEL test: 16.44 ± 2.55; and flow cytometry test: 23.56 ± 2.22), the expression of pro-apoptotic proteins Bax, Smac and Cytochrome c were increased in the LPS group, while the expression of anti-apoptotic proteins Bcl-2 and tight junction protein were decreased. In the LPS group. Cellular immunofluorescence results showed that the ZO-1 was degraded in the cell membrane and the network structure was broken. Compared with the LPS group, inhibition of ERRα in the shERRα+LPS group increased cell damage.Conclusions:ERRα can negatively regulate the apoptosis and affect the function of pulmonary microvascular endothelial cells, thereby regulating sepsis-induced acute lung injury.
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Motor timing is an important part of sensorimotor control. Previous studies have shown that beta oscillations embody the process of temporal perception in explicit timing tasks. In contrast, studies focusing on beta oscillations in implicit timing tasks are lacking. In this study, we set up an implicit motor timing task and found a modulation pattern of beta oscillations with temporal perception during movement preparation. We trained two macaques in a repetitive visually-guided reach-to-grasp task with different holding intervals. Spikes and local field potentials were recorded from microelectrode arrays in the primary motor cortex, primary somatosensory cortex, and posterior parietal cortex. We analyzed the association between beta oscillations and temporal interval in fixed-duration experiments (500 ms as the Short Group and 1500 ms as the Long Group) and random-duration experiments (500 ms to 1500 ms). The results showed that the peak beta frequencies in both experiments ranged from 15 Hz to 25 Hz. The beta power was higher during the hold period than the movement (reach and grasp) period. Further, in the fixed-duration experiments, the mean power as well as the maximum rate of change of beta power in the first 300 ms were higher in the Short Group than in the Long Group when aligned with the Center Hit event. In contrast, in the random-duration experiments, the corresponding values showed no statistical differences among groups. The peak latency of beta power was shorter in the Short Group than in the Long Group in the fixed-duration experiments, while no consistent modulation pattern was found in the random-duration experiments. These results indicate that beta oscillations can modulate with temporal interval in their power mode. The synchronization period of beta power could reflect the cognitive set maintaining working memory of the temporal structure and attention.
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Objective To study binocular rivalry (BR)objectively and the correlation between fusiform face area (FFA)and visual cortex.Methods Six subjects participated in this study,with one eye presented a normal face expres-sion picture flickered at 8.57 Hz,while the other presented a fearful face flickered at 12 Hz or 15 Hz,respectively.Electro-encephalogram(EEG)was recorded during this process.Steady state visual evoked potential(SSVEP)evoked by two flick-ering rates was analyzed by time-frequency analysis of short time fourier transformation(STFT).The time index of BR was estimated and the correlation coefficient between FFA and visual cortex compared.Results The total average time was (411.6 ±73.8)ms for the left eye and (547.6 ±126.7)ms for the right eye.The switch rate of the two groups was not different,but the left FFA was more sensitive than the right FFA in process of the fearful face.Neither side of FFA had any frequency preference to the flickered fearful face.Conclusion SSVEP can be used as a frequency tag of BR or as a tool to evaluate visual sensation under BR objectively.SSVEP combined with BR can be used in research of neural mechanisms of visual awareness.
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Objective To establish a key technological system for spider fibroin gene code tandem connection , vector construction , prokaryotic expression and purification using genetic engineering in order to achieve MaSp 1 heterologous ex-pression in Escherichia coli and its separation and purification .Methods Isocaudarner ligation method was used to connect synthetic spider fibroin gene monomer code in tandem , and a recombinant clone concatemer was obtained .The identified recombinant clones were connected with prokaryotic expression vector pET 28a(+), and then transformed into E.coli BL21 (DE3).After being induced by IPTG for 6 hours, the expression product was identified by SDS-PAGE and Western blot-ting.Engineering bacteria were fermented in high density , and the obtained protein was purified through ammonium sulfate fractionation.Results and Conclusion The expression plasmids of MaSp1concatemers were successfully constructed , and the induced expression genetic engineering MaSp 1 protein was of the expected relative molecular mass .In addition, the pu-rity of the purified protein was above 80%.This study has developed crucial technologies for mass production of genetic en-gineering spider silk proteins .
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Objective To investigate the cell survival of the combination of fibrin glue and adiposederived stem cells (ADSCs) in rats when implanted into ischemic myocardium and the improvement of heart function.Methods The rat ADSCs were isolated from the subcutaneous adipose tissues.The surface phenotype of these cells was analyzed by flow cytometry.Myocardial infarction was induced in female rats using coronary artery ligation.One week after MI,surviving rats were randomized (random nuber) into 4 groups,control group (n =10),fibrin group (n =10),cell group (n =10) and combination group (n =10).100 μl of PBS was injected into the ischemic myocardium in control group.100 μl of Fibrin glue were injected into ischemic myocardium in fibrin group.100 μl of ADSCs labeled with DAPI were injected into the infract along the border zone in cell group.ADSCs in 100 μl of fibrin glue were injected into the infract in combination group.Four weeks after the injection the surviving rats underwent examination of heart functions by the Hemodynamics.The rats were killed and their hearts were taken out to undergo immunohistochemistry with 4,6-diamidino-2-phenylindole (DAPI) and actin and factor Ⅶ to measure the area of cardiac infarction and the capillary density.The heart infarcted size was calculated by masson trichrome staining.All data was analyzed by software SPSS 15.0,ANOVA comparison tests and the student t test were used,and P ＜ 0.05 was considered as statistically significant.Results Four weeks after the cells were transplanted,LVSP and + dp/dtmax of combination group were highest among all groups.The heart infarcted size of the combination group was (28.5 ± 3.6) ％,significantly less than those of the cell group (33.33 ± 2.3) ％ and fibrin group (35.96 ± 2.11) ％,both P ＜ 0.05.The capillary density of the combination group was (108.7 ± 11.38) /mm2,significantly greater than those of the cell group and that of the fibrin group,and greater than that of the control group.DAPI and actin double staining detected a varied increase in the number of surviving cardiomyoctyes at the heart infarcted area.Conclusions Transplantation of ADSCs with fibrin glue brings better improvement in cell survival and in restoration of heart function than either cellular or fibrin therapy alone.
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@#ObjectiveTo test and verify whether Ba-alginate-Poly-L-Ornithine-Alginate microcapsules(B-PLO-A) can improve the physical properties and biocompatibility of the traditional BPA microcapsules.MethodsThe B-PLO-A and Ba-alginate-Poly-L-lysine-alginate（B-PLL-A） microcapsules were made by the static generator. The physical property of the microcapsules was evaluated by observing the morphological changes of the microcapsules in the hypotonic environment, changes in diameter of microcapsules in vitro culture and calculating broken microcapsules ratio by shaking method. The biocompatibility was observed by transplanting into peritoneal cavity of rat.ResultsB-PLO-A microcapsules are stronger and more stable in a hypotonic environment than B-PLL-A microcapsules. After 96 h mechanism shaking, the unbroken microcapsules ratio of B-PLO-A and B-PLL-A microcapsules were (99.3±1.0)% and (96.2±1.5)% respectively. The microcapsules were retrieved from peritoneal cavity of rat at 2, 4 and 8 weeks after transplantation, most of the microcapsules were of integrity, rotundity, and surface smooth without obviously bundled by connective tissue. 8 weeks after transplantation the intact microcapsules ratio of B-PLO-A and B-PLL-A microcapsules were (97.3±2.1)% and (95.4±2.4)% respectively.ConclusionB-PLO-A microcapsules as a whole have bettermechanical strength compared with B-PLL-A microcapsules, while maintaining a good biocompatibility.
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@#Objective To reconstruct tissue-engineered 3D bronchial model using human bronchial epithelial cells and human embryo lung fibroblast as seeding cells, and liquid collagen mixed Matrigel as scaffold. Methods Human bronchial epithelial cells and human embryo lung fibroblast were mixed with liquid collagen supplementing with matrigel and casted in 12-wells plate to reconstruct cells-collagen sheet. Macroscopic observation, phase-contrast microscopy observation, routine HE staining and immunohistochemistry staining(CK ets) were employed to assess the engineered 3D model. Results We reconstructed engineered 3D bronchial model successfully in vitro by tissue engineering techniques and exerted static stretch onto the collagen sheet. From Macroscopic observation, we gained contracted well sheet. We also observed network structure in phase-contrast microscopy meanwhile the viability of cells was fine. HE staining showed the formation of 3D network structure. The immunohistochemistry staining of CK and Vimentin were positive.Conclusion We reconstructed engineered 3D bronchial model successfully in vitro and seeding cells could implement polarity growing in the scaffold materials then gained the network structure.
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Tissue-engineering bone with porous ,betatricalcium phosphate (3-TCP) ceramic and autologous bone marrow mesenchymal stem cells (MSC) was constructed and the effect of this composite on healing of segmental bone defects was investigated. 10-15 ml bone marrow aspirates were harvested from the iliac crest of sheep, and enriched for MSC by density gradient centrifugation over a Percoll cushion (1. 073 g/ml). After cultured and proliferated, tissue-engineering bones were constructed with these,cellS seeded onto porous f-TCP, and then the constructs were implanted in 8 sheep left metatarsus defect (25 mm in length) as experimental group. Porous ,-TCP only were implanted to bridge same size and position defects in 8 sheep as control group, and 25 mm segmental bone defects of left metatarsus were left empty in 4 sheep as blank group. Sheep were sacrificed on the 6th, 12th, and 24th week postoperatively and the implants samples were examined by radiograph, histology, and biomechanical test. The 4 sheep in blank group were sacrificed on the 24th week postoperatively. The results showed that new bone tissues were observed either radiographic or histologically at the defects of experimental group as early as 6th week postoperatively, but not in control group, and osteoid tissue, woven bone and lamellar bone occurred earlier than in control group in which the bone defects were repaired in "creep substitution" way, because of the new bone formed in direct manner without progression through a cartilaginous intermediate. At the 24th week, radiographs and biomechanical test revealed an almost complete repair of the defect of experimental group, only partly in control group. The bone defects in blank group were non-healing at the 24th week. It was concluded that engineering bones constructed with porous -TCP and autologous MSC were capable of repairing segmental bone defects in sheep metatarsus beyond "creep substitution" way and making it healed earlier. Porous ,-TCP being constituted with autologous MSC may be a good option in healing critical segmental bone defects in clinical practice and provide insight for future clinical repair of segmental defect.
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Bone Marrow Cells/cytology , Calcium Phosphates/pharmacology , Cells, Cultured , Fractures, Bone/therapy , Implants, Experimental , Mesenchymal Stem Cells/cytology , Metatarsus/injuries , Porosity , Sheep , Tissue EngineeringABSTRACT
Tissue-engineering bone with porous β-tricalcium phosphate (β-TCP) ceramic and autologous bone marrow mesenchymal stem cells (MSC) was constructed and the effect of this composite on healing of segmental bone defects was investigated. 10-15 ml bone marrow aspirates were harvested from the iliac crestof sheep, and enriched for MSC by density gradient centrifugation over a Percoll cushion (1. 073 g/ml). After cultured and proliferated, tissue-engineering bones were constructed with these cells seeded onto porous β-TCP, and then the constructs were implanted in 8 sheep left metatarsus defect (25 mm in length) as experimental group. Porous β-TCP only were implanted to bridge same size and position defects in 8 sheep as control group, and 25 mm segmental bone defects of left metatarsus were left empty in 4 sheep as blank group. Sheep were sacrificed on the 6th, 12th, and 24th week postoperatively and the implants samples were examined by radiograph, histology, and biomechanical test. The 4 sheep in blank group were sacrificed on the 24th week postoperatively. The results showed that new bone tissues were observed either radiographic or histologically at the defects of experimental group as early as 6th week postoperatively, but not in control group, and osteoid tissue, woven bone and lamellar bone occurred earlier than in control group in which the bone defects were repaired in "creep substitution" way, because of the new bone formed in direct manner without progression through a cartilaginous intermediate. At the 24th week, radiographs and biomechanical test revealed an almost complete repair of the defect of experimental group, only partly in control group. The bone defects in blank group were non-healing at the 24th week. It was concluded that engineering bones constructed with porous β-TCP and autologous MSC were capable of repairing segmental bone defects in sheep metatarsus beyond "creep substitution" way and making it healed earlier. Porous β-TCP being constituted with autologous MSC may be a good option in healing critical segmental bonedefects in clinical practice and provide insight for future clinical repair of segmental defect.
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BACKGROUND:Bone marrow derived mesenchymal stem cells (BMMSCs) have multi-differentiation potentials, possessing a repairing capability for the sectional bone defects if combined with degradable porous β-tricalcium phosphate china. This provides a new idea in clinical repair of various bone defects.OBJECTIVE: To explore in radiology the curative effect of implanting porous β-tricalcium phosphate and autogenous BMMSCs compound to treat bone defects.DESIGN: A randomized controlled study with callus growth at various healing periods as subjects for observation. SETTING: Department of Orthopaedics, Renmin Hospital, Wuhan University; Tissue Engineering Center, Research Institute of Basic Medicine,Academy of Military Medical Sciences of Chinese PLAMATERIALS: This experiment was carried out at the Tissue Engineering Center, Research Institute of Basic Medicine, Academy of Military Medical Sciences of Chinese PLA between March and September 2002. Twenty China healthy adult sheep were randomized into the groups of blank control group (4 sheep), simple implantation group (8 sheep) and complex implantation group (8 sheep).METHODS: Under general anesthesia and aseptic condition, 10-15 mL of sheep marrow was extracted; MSCs were separated and cultured before combined with porous β-tricalcium phosphate china for tissue engineering bone construction. Rats in each group were cut off 21mm long metatarsus in the middle section of metatarsus bonestem. Β-tricalcium phosphate china and autogenous MSC compound was implanted into the sheep of the complex implantation group; β-tricalcium phosphate china was implanted into the simple implantation group; and the bone defects in the blank control group remained untouched. Then the incision was sutured.X-ray filming was carried out right after the operation, as well as 1, 3,and 6 months after the operation for radiological appraisal (scored for1 if bone union formed in one surface of bone defect, but scored 0 if no boneunion formed in any surface of bone defect, and scored 4 if bone union formed in front, back, lateral surfaces and the center of bone defect), Xray radiation-resisting density was analyzed to compare the results of bone defect repair.MAIN OUTCOME MEASURES: The postoperative general condition and general observation, as well as the results of the radiological analysis of the bone defects of all sheep.RESULTS: Totally 20 sheep were brought into this xperiment and all entered the stage of result analysis. ① The postoperative general condition:Sheep regained consciousness 2-6 hours after the operation without incision infection and loosing of internal fixation. Their spirit gradually was back to normal 1 week after the operation, at which time the injured legs could touch ground but were incapable of bearing load, and the affected legs could bear load 2 weeks after the operation, walked slightly lamely 3 weeks after the operation, and even moved freely without limp 4 weeks after the operation. ②The general condition 6 months after the operation: In pure implantation group, the surface white hyaline cartilage-like tissues were gradually calcified, with both ends connected with the host bone by bone bridge, but china granules could still be easily observed; while no implantation substance could be observed in compound implantation group,with the boundary between implantation substance and host bone vanished,and bone defect became basically the same as host bone. However there was no bone tissue formed in bone defect at various postoperative time points in the blank control group. ③ Radiological analysis of the bone defects at various postoperative time points: The radiological rating score was obviously higher in complex implantation group at the time poin ts of 3, 6 months after the operation compared with the pure implantation group [(2.3±0.3), (1.8±0.5); (3.3±0.5), (2.6±0.6), P ＜ 0.05]. ④ Radiological analysis of bone callus thickness and the relative value of radiation-resisting density at various postoperative time points: The bone callus thickness in the complex implantation group was obviously lower than that of the pure implantation group at the postoperative time point of 6 months (4.62 vs 7.64, P ＜ 0.05), with relative value of radiation-resisting density obviously higher than that of the pure implantation group (70.4±1.5 vs 61.18±1.2, P ＜ 0.05).CONCLUSION: Radiological appraisal and bone defect density measurement can well reflect the dynamical repairing process of bone defects; the implantation of porous β-tricalcium phosphate china and autogenous BMMSCs compound into sheep can enhance the repair of large sectional bone defect.
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Objective To study the method of preparation and blood sugar lowering effect of oral chitosan-insulin nanoparticles (INS-NPs) in streptozotocin-induced diabetic Wistar rats. Methods The INS-NPs were prepared by an ionic gelation method. The changes in the morphology and size of the INS-NPs were observed with transmission electron microscope and Zetasizer 3000HS, respectively. The blood sugar lowering effect of the INS-NPs was evaluated by monitoring the blood glucose levels in healthy and streptozotocin-induced diabetic rats. Results INS-NPs were spherical in shape with a mean size of 220.6±15.9nm. Entrapment efficiency of INS-NPs was 75.4%±3.2% and the loading efficiency of INS-NPs was 19.5%±2.6%. In vivo blood sugar lowering study showed that the levels of blood glucose of healthy Wistar rats were significantly reduced from 6h to 12h after oral administration of INS-NPs(25U/kg). The blood glucose level of diabetic rats were significantly reduced at 6h after oral administration of INS-NPs (25U/kg), and this effect was maintained for more than 9h, and the levels of blood glucose were kept in normal range for 7h. Conclusion The INS-NPs prepared by ionic gelation method has the blood glucose lowering effect in streptozotocin-induced diabetic Wistar rats.
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BACKGROUND:Sirius red is a strong acid anionic dye. Being not-easyto-fade and specific, sirius red becomes the best dye for collagen staining.Collagen is a major component of extracellular matrix and has some specific physiological functions. Through synthesis and reconstruction of collagen, bone fracture repair will be accomplished.OBJECTIVE: Picric acid-Sirius red stained slides were observed under a polarized light microscopy for evaluation the dynamic changes in the ratio of different collagen types and their distributions in bone fracture healing.DESIGN: It was a controlled observation.SETTING: It was conducted in the Department of Orthopedics, Renmin Hospital, Wuhan University; Department of Traumatic Orthopaedics, Tianjin Hospital; Department of Traumatic Orthopaedics, Jishuitan Hospital,Medical Department, Peking University; Tissue Engineering Center of Institute of Basic Medical Sciences, Academy of Military Medical Sciences of Chinese PLAMATERIALS: It was conducted at Tissue Engineering Center of Institute of Basic Medical Sciences, Academy of Military Medical Sciences of Chinese PLA from March 2002 to September 2003. Three healthy adult Chinese sheep, male and in weight from 25 to 35 g, were selected.METHODS: All the animals were anesthesized and sterilized; a transverse osteotomy of the trunk of metatarsus was performed; and the end of fracture was fixed with a six-hole Medoff sliding plate. At the post-operative month 1, 3 and 6, samples were taken from bone fractures. After decalcification with EDTA, they were stained with Picric acid-sirius red, and the types and distribution of collagens were observed under a polarized light microscopy.MAIN OUTCOME MEASURES: Types and distributions of collagens in bone lesion in different period of bone healing were investigated.RESULTS: Three sheep used in this study entered the statistical analysis.①Morphological features of various collagens under a polarized light microscopy postoperatively: Type Ⅰ collagen packed tightly, with a strong refraction and yellow, orange or red thick fibres. Type Ⅱ collagen formed a loose reticulation with fibres exhibiting different colour and a weak refraction. Thin fibres of type Ⅲ collagen with weak refraction and green colour formed a loose reticulation. ②Quantitative studies on various collagens under a polarized light microscopy postoperatively: At postoperative month 1,red or orange fibres (type Ⅰ collagen) were rarely seen in bone fracture,while green fibres (typical of type Ⅲ collagen) were dominant with a disorder pack. At postoperative month 3, red or orange fibres increased significantly and the ratio of type Ⅲ collagen reduced. The collagen fibres assembled regularly. At postoperative month 6, thick yellow-red collagen became dominant and thin green type Ⅲ collagen decreased dramatically and arranged in an obvious oblique, spiral and crossed orientations.CONCLUSION: Picric acid-sirius red stain combined with polarized light microscopy technique is not only capable of identifing type Ⅰ and type Ⅲ collagens in bone fraction, but also can reflect the morphological features,distribution and the ratio of these two type collagens. This approach has the virtues of easiness in operation, strong specificity and high sensitivity.
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In order to study the chondrogenic phenotype differentiation of adult sheep bone marrow-derived mesenchymal stem cells (MSCs) in a defined medium as potential seed cells for cartilage tissue engineering. MSCs were isolated by density centrifugation with Percoll solution from bone marrow aspirated from sheep iliac crest. The third passage of MSCs were induced with H-DMEM containing TGF-beta3, IGF-I, Dexamethasone and VitC. The shape and ultrastructure of cells were observed, toluidine blue stain for GAG and immunohistochemistry for type II collagen were applied for chondrogenic phenotype identification. After 14 days of induction, MSCs changed from a spindle-like appearance to a polynal shape, a large amount of endoplasmic reticulum, Golgi complex and mitochondria were observed, and the differentiation of MSCs chondrogenic phenotype was verified by positive staining of toluidine blue and immunohistochemistry. MSCs derived from bone marrow can differentiate to chondrogenic phenotype when induced in vitro and can be used as optimal seed cells for cartilage tissue engineering.
Subject(s)
Animals , Bone Marrow Cells , Cell Biology , Cell Differentiation , Cell Separation , Cells, Cultured , Chondrocytes , Cell Biology , Chondrogenesis , Mesenchymal Stem Cells , Cell Biology , Phenotype , Sheep , Tissue EngineeringABSTRACT
In order to study the chondrogenic phenotype differentiation of adult sheep bone marrow-derived mesenchymal stem cells (MSCs) in a defined medium as potential seed cells for cartilage tissue engineering. MSCs were isolated by density centrifugation with Percoll solution from bone marrow aspirated from sheep iliac crest. The third passage of MSCs were induced with H-DMEM containing TGF-beta3, IGF-I, Dexamethasone and VitC. The shape and ultrastructure of cells were observed, toluidine blue stain for GAG and immunohistochemistry for type II collagen were applied for chondrogenic phenotype identification. After 14 days of induction, MSCs changed from a spindle-like appearance to a polynal shape, a large amount of endoplasmic reticulum, Golgi complex and mitochondria were observed, and the differentiation of MSCs chondrogenic phenotype was verified by positive staining of toluidine blue and immunohistochemistry. MSCs derived from bone marrow can differentiate to chondrogenic phenotype when induced in vitro and can be used as optimal seed cells for cartilage tissue engineering.
Subject(s)
Bone Marrow Cells/cytology , Cell Differentiation , Cell Separation , Cells, Cultured , Chondrocytes/cytology , Chondrogenesis , Mesenchymal Stem Cells/cytology , Phenotype , Sheep , Tissue EngineeringABSTRACT
Objective To explore the method and technique to gain adequate seed cells for cartilage tissue engineering Methods hTERT gene was introduced into rabbit mandibular condylar chondrocytes by eukaryotic vector Rapidly proliferated immortalized chondrocytes in positive clones in micro carrier rotary cell culture system (RCCS) were screened and selected The growth of immortalized chondrocytes and the metabolic rate were observed Collagen type Ⅱ expression of immortalized chondrocytes of the experimental groups was observed The immunohistochemical results were compared with those of the control groups Results The immortalized chondrocytes in experimental groups could grow rapidly with a high metabolic rate and shorter population doubling time (PD) ( P
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Objective To explore the feasibility of the construction and formation of cartilage with immortalized chondrocytes by tissue engineering technology in vitro . Methods Human telomerase reverse transcriptase(hTERT) gene was introduced into rabbit mandibular condylar chondrocytes by eukaryotic vector. After screening with G418, the positive clones were amplified for culture. Normal or immortalized chondrocyte loaded cytoskeleton ? tricalcium phosphate (? TCP) complexes were incubated in vitro for 1～2 d and then implanted into subcutaneous tissue of nude mouse. The complexes of immortalized chondrocyte ? TCP and chondrocyte ? TCP or ? TCP alone were established as the experimental group and control groups respectively. The specimens were harvested within 3 and 6 months after surgical procedure for histological and immunohistochemical observation. Results In experimental groups and control group 1, the complexes packed with cartilage like tissue were found, but there was only a little fiber like tissue formed in control group 2. Immunohistochemistry revealed strong positive staining with safranine O, toluidine blue and collagen type II and obvious formation of cartilage. There was significant difference between the experimental group and the control groups( P
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<p><b>OBJECTIVE</b>To study telomerase activity and expression of oncogenes c-myc and p53 in tongue cancer, analyse the interaction among them, and assess their possible correlations with tongue cancer clinicopathological features.</p><p><b>METHODS</b>To detective the telomerase activity by TRAP and examine the positive expression of c-myc and p53 in tongue cancer by hybridization in situ.</p><p><b>RESULTS</b>A high telomerase activity existed in lower differentiated tongue cancer (P < 0.05); the positive expression of c-myc increased significantly in lower grade tongue cancer (P < 0.05) and the positive expression of p53 decreased increasingly in tongue cancer accompanied with lymph node metastasis (P < 0.05).</p><p><b>CONCLUSION</b>Telomerase may play a key role in the tumorigenesis of tongue cancer. Meantime, c-myc and p53 exerts important effect on telomerase activation during the course of tongue cancer generation and development.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Adenocarcinoma , Genetics , Metabolism , Carcinoma, Squamous Cell , Genetics , Metabolism , Lymphatic Metastasis , Proto-Oncogene Proteins c-myc , Genetics , Telomerase , Metabolism , Tongue Neoplasms , Genetics , Metabolism , Tumor Suppressor Protein p53 , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the feasibility of growing tissue-engineered cartilage using chondrocytes seeded onto a biodegradable porous bioceramic, the beta-tricalcium phosphate (beta-TCP).</p><p><b>METHODS</b>A porous bioceramic template of beta-TCP was created in the shape of a disc. Chondrocytes isolated from rabbit articular cartilage were seeded on the beta-TCP template and then kept in rotatory cell culture system (RCCS) for 1 week prior to subcutaneous transplantation into athymic mice. The three-dimensional structure was well-maintained 16 weeks after implantation. After 4, 8, 16 weeks, the specimens were harvested and examined macroscopically, histologically and immunohistochemically.</p><p><b>RESULTS</b>Gross morphological and histological analysis of the specimens from the chondrocyte-beta-TCP complex demonstrated new cartilage construction. The overall configuration of the experimental specimens closely resembled the structure of beta-TCP template.</p><p><b>CONCLUSION</b>These findings suggest that porous bioceramic (beta-TCP) is a good "matrix" for chondrocyte, and can be used for cartilage engineering.</p>