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81.
Background contextIt was recently demonstrated that the postnatal transition from a notochordal to a fibrocartilaginous nucleus pulposus (NP) is accomplished exogenously by chondrocytes migrating from hyaline cartilage end plates (CEs) into the ectopic notochordal NP region. Although our previous in vivo studies showed evidences for the migration of CE chondrocyte from hyaline CEs into the notochordal NP, it is unknown whether CE chondrocytes of the intervertebral disc (IVD) really have a motile property. In addition, the effect of notochordal cells on this property has not been elucidated.PurposeThe purpose of this in vitro study was to demonstrate whether CE chondrocytes of the IVD are capable of migration, and whether there is any biological link between notochordal cells and CE chondrocytes that may regulate the CE chondrocyte migration.Study design/settingIn vitro cell migration assays were performed using rat IVDs.MethodsNotochordal cells and chondrocytes were obtained from the NP and CE tissues, respectively, and were cultured separately. The different numbers of notochordal cells and the supernatant (conditioned medium) that contained soluble factors produced by notochordal cells were used to demonstrate their effects on the migration of CE chondrocytes. Bovine serum albumin (BSA) and lysophosphatidic acid (LPA) were used as negative and positive controls, respectively.ResultsCompared with BSA, LPA, notochordal cells (N=4×, 2×, 1×, and 0.5×105), and its conditioned media (unconcentrated and fivefold concentrated) significantly increased migration of CE chondrocytes (p<.05 in all comparisons). Particularly, notochordal cells and its conditioned media increased migration in a number- and concentration-dependent manner, respectively.ConclusionsThis study demonstrates that CE chondrocytes of the IVD are capable of migration and that soluble factors produced by notochordal cells stimulate the migration. These results provide a plausible explanation to the question of why CE chondrocytes of the IVD migrate into the ectopic NP region during the natural transition from the notochordal to fibrocartilaginous NP.  相似文献   
82.
The neutral lipids existing in the intercellular spaces of the stratum corneum (SC) provide a permeability barrier to prevent water loss. Nile red is the most sensitive lipid stain for tissue sections. However, due to the extremely flattened morphology of corneocytes and the resolution limits of the light microscope, Nile red staining is seldom used as a fluorescent probe for the lipid-rich SC. In this study, we modified the traditional method for visualization of intracellular lipid by adding 4% potassium hydroxide after Nile red staining. This modified method not only allowed visualization of lipids existing in the intercellular membrane regions and the lateral junctions of the adjoining corneocytes, but also clearly demonstrated small lipid droplets within pathological corneocytes. These features were not observed with the traditional staining method. Thus, this modified Nile red staining method greatly improved the resolution of the SC lipids under light microscopy and should be useful for studying lipid depositions in both normal and pathological SC.  相似文献   
83.
Parenchymal disease in the allograft lung is associated with interstitial remodeling believed to be mediated by matrix metalloproteinases (MMPs). Recent studies suggest high levels of MMP-9 are associated with bronchiolitis obliterans syndrome (BOS) in lung transplant recipients. Since BOS occurs late in the posttransplant period and may be preceded by episodes of acute rejection or infection, which are associated with interstitial remodeling, we examined MMP profiles in allograft bronchoalveolar lavage (BAL) fluid in the early posttransplant period (preceding BOS). Gelatin zymography, protein array analysis and specific ELISA on BAL fluids from transplanted lungs indicated that MMP-8, MMP-9 and TIMP-1 were strongly expressed in allograft BAL fluid from stable patients, or those with infection or rejection compared to BAL fluid from normal volunteers. Elevated expression of MMP-8, MMP-9 and TIMP-1 occurred early, and was sustained for the 3.2 years covered in this study. Elevations of MMP-8, MMP-9 and TIMP-1 in the first 2 years posttransplant appear to be associated with lung transplantation itself, and not infection or rejection. These data suggest that ongoing and clinically silent MMP activity could perpetuate progressive disease in the allograft lung.  相似文献   
84.
OBJECTIVE: Pamidronate has been studied as a therapeutic drug for various osteopenic diseases. However, avascular osteonecrosis in the jawbone has been recently reported in patients receiving pamidronate. The objective of this study was to examine the effect of pamidronate on bone regeneration in a controlled animal model. MATERIALS AND METHODS: To determine the effect of parmidronate on bone healing in a local bony defect area, a rabbit calvarial bony defect model was used and poly L-lactide-co-glycolide (PLGA) used as a drug carrier material. Four defect groups were made in each rabbit calvaria and the defects were treated as follows: untreated bony defect (group 1), PLGA only (group 2), 2 mg of pamidronate with PLGA (group 3), and 3 mg of pamidronate with PLGA (group 4). Bone healing was evaluated by radiography and histology at 1, 2, 4, 6, and 8 weeks after surgery. RESULTS: In radiographic analysis, radiopacity was lower in pamidronate groups than non-operated rabbit calvarial bone at all observation points (P < .05). In histological analysis, the initial bone formation at 1 week was not different among groups, but it was much lower in the pamidronate groups than in the control or PLGA group after 2 weeks. Newly formed bone at 1 week underwent avascular necrosis after 2 weeks in both pamidronate groups. Avascular necrosis was not observed until 8 weeks in both topically applied pamidronate groups. CONCLUSION: Collectively, pamidronate inhibits bone healing in rabbit calvarial bony defect and it may explain the avascular necrosis of the jaws in patients receiving pamidronate.  相似文献   
85.
邻近皮瓣修复面部皮肤缺损   总被引:1,自引:0,他引:1  
目的 探讨邻近皮瓣修复面部皮肤缺损的应用效果。方法 162例面部病变切除后皮肤缺损患者,其中先天性色素痣63例,基底细胞癌28例,鳞状细胞癌6例,其他皮肤病变65例。均采用邻近皮瓣即时修复,其中菱形皮瓣57例、双叶皮瓣8例,A-T皮瓣23例、V-Y皮瓣13例、Z成形术23例、推进皮瓣27例、鼻状皮瓣11例。结果 162例皮瓣存活良好,手术切口1期愈合,存活后皮瓣颜色与邻近部位无明显差异,术后无眼睑、眉毛、鼻梁及口角牵扯歪钭,术后3个月切口不显露。结论 邻近皮瓣是修复面部较大皮肤缺损的良好方法,手术外观效果好。  相似文献   
86.
原发性三叉神经痛的LEKSELL-C伽玛刀治疗   总被引:1,自引:0,他引:1  
目的 探讨伽玛刀治疗原发性三叉神经痛的方法和效果.方法 对28例原发性三叉神经痛采用LEKSELL-C型伽玛刀治疗,均沿三叉神经走行在三叉神经根近桥脑处选择双靶点治疗.中心剂量75~85Gy,50%等剂量线限定靶点.结果 随访3~11个月,疼痛消失时间平均在术后3.5个月.按疼痛缓解评分,在随访时点,总有效率为96%.结论 LEKSELL-C型伽玛刀是治疗原发性三叉神经痛安全和有效的方法之一.  相似文献   
87.
荧光示踪法研究逆行岛状皮瓣静脉回流   总被引:3,自引:0,他引:3  
目的探讨采用荧光示踪法研究逆行岛状皮瓣静脉回流的可行性,并初步观察静脉回流规律。方法20只新西兰大白兔,每只取耳静脉血0.ImL,分离RBC并用FITC标记。流式细胞仪检测已标记的RBC阳性率及荧光强度,倒置荧光显微镜观察其形态。取20只新西兰大白兔,在动物双侧后肢内侧分别建立4cm&#215;3cm隐动、静脉逆行岛状皮瓣模型(n=10)和顺行岛状皮瓣模型(n=10),血管蒂长3cm。将一侧后肢随机设定为实验组,皮瓣制备后注射已标记的RBC悬液5pL;对侧为对照组,不注射示踪剂。实验组按顺行和逆行皮瓣分成两组,即顺行皮瓣组和逆行皮瓣组,每组10个;再根据注入示踪剂途径不同,分为动脉和静脉2个亚组,每亚组5个皮瓣。注射示踪剂5S后取下皮瓣立即冷冻,取连续的3张冰冻切片(5~7pm),其中2张行HE染色和GENMED染色,另]张不染色直接压片,荧光显微镜观察荧光分布。结果流式细胞仪分析FITC标记的RBC阳性率在99%以上,荧光强度均≥10。;倒置荧光显微镜下标记的RBC呈均匀分布的绿色荧光,荧光强度均匀、稳定。冰冻切片显示实验组皮瓣蒂部均出现荧光,对照组未见荧光。顺行岛状皮瓣组荧光主要分布在静脉腔、静脉壁、动脉内膜和外膜;逆行岛状皮瓣组荧光分布在动脉内膜、外膜和静脉壁。结论荧光示踪剂可用于静脉回流研究,顺行岛状皮瓣静脉主要通过静脉腔、静脉壁、动脉内膜和外膜回流;逆行岛状皮瓣静脉主要通过动脉内膜、外膜和静脉壁的“迷宫式途径”回流。  相似文献   
88.
目的:总结Ⅰ期在第2足趾游离移植再造拇(手)指中行趾甲延长的临床应用经验.方法:采用趾甲延长方法对9例(男7,女2例)第2足趾移植再造拇(手)指的患者进行了趾甲延长术,其中拇指8例,食指1例.年龄18~46岁,平均25岁.在再造指距甲根皮缘5 mm处,去除1块矩形皮肤,勿损伤皮下血管网.其高度2 mm,宽度与趾甲相等,将U形皮瓣向近端柔和推剥并缝合.结果:1例术后供区发生表浅感染,经换敷料逐渐愈合.再造的拇(手)指全部成活,可延长趾甲2~3 mm,改善了再造拇(手)指的外形,无指甲生长畸形发生.随访7个月~2年(平均13个月),趾甲外形较好.结论:在第2足趾游离移植再造拇(手)指中应用Ⅰ期趾甲延长术,使趾甲从短小向纵向延长,缩小手指甲与足趾甲之间差异,能改善再造拇(手)指甲外形,且不影响再造指的活动功能,是一种简单有效的手术方法.  相似文献   
89.
90.
S L Lee 《JAMA》1991,266(2):217-218
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