IL-1诱导髁状突软骨细胞凋亡的实验研究

观察IL - 1对髁状突软骨 (Mandibularcondylarcartilage ,MCC)细胞增殖及凋亡的影响。 方法下颌骨髁状突软骨取自 6只新生的日本大耳白兔 ,经机械分离及胰蛋白酶、胶原酶联合消化获得MCC细胞。取第2代软骨细胞 ,培养过程中培养液中加入不同浓度 (0 .1μg/L、10 0 μg/L)的IL - 1,采用相差显微镜、流式细胞术及透射电镜对髁状突软骨细胞生物学行为变化进行研究。结果　IL - 1在 1μg/L～ 10 0 μg/L范围内 ,呈剂量效应关系抑制髁状突软骨细胞增殖 ,流式细胞术结果表明MCC细胞多数阻断于G0 /G1期 ,S期细胞比例显著低于对照组(P <0 .0 5 )。同时 10 μg/L及 10 0 μg/LIL - 1可显著诱导细胞凋亡 (凋亡率分别为5 9.47%及 6 3 .73 % ) ,细胞收缩 ,形态变圆。电镜下观 ,胞浆浓缩 ,染色质边集 ,粗面内质网扩张。结论　IL - 1抑制MCC的细胞增殖 ,诱导细胞凋亡的发生 ,可能是其在骨关节病发病中重要作用途径之一。     

下颌髁突软骨细胞凋亡的研究

近年来，有关软骨发育和软骨疾病中软骨细胞凋亡及各种调节因素逐渐受到人们重视。本文对下颌髁突软骨及其病变中的细胞凋亡及调节因素作一综述。     

下颌髁突软骨胞外基质的研究

软骨中胞外基质含量丰富,主要包括胶原、蛋白多糖和结构蛋白。下颌髁突软骨是较特殊的软骨,现对胞外基质在下颌髁突软骨中的分布及其与软骨细胞分化关系作一综述。     

颞颌关节手术非手术侧髁状突软骨氨基多糖的观察

作者采用组织化学方法，观察了实验动物（兔）一侧关节髁突高位切除术后非手术侧关节髁状突软骨氨基多糖含量的变化，结果显示非手术侧髁状突软骨基质中氨基多糖含量减少，并随实验周期的延长而有一定程度的加重。     

髁状突软骨纤维组织的超微结构观察

目的：深入了解髁突内部纤维组织的结构、走行方向、相互间关系及功能。方法：用扫描电镜和透射电镜观察了8例(16侧)家兔，体重为1．5—2．0kg，月龄6个月(动物由同济医学院中心实验室提供)。颞下颌关节髁状突剖面和切削面的超微结构。结果：在扫描电镜下，剖面呈现纵横交错的立体网状结构或者类似海绵状结构；切削处可见浅层的纤细网状纤维，这种纤维与泥土样物混合交织形成软骨的外层；在网状纤维的深层可见三种粗大的纤维平行于髁状突表面走行，其直径分别约为20nm、35nm和100nm。不同部位的纤维的排列、走向不尽相同。透射电镜下，髁状突内部纤维主要是有明显周期性横纹的I型胶原。结论：①髁状突表层存在一层纤细的网状纤维。②深层纵横交错的纤维呈海绵状结构具有传导和分散压力的作用。③纤维的粗细不同可吸收各种振动频率的力，形成了对作用于颞下颌关节各种力的有效缓冲垫。④透射电镜下纤维属I型胶原，说明髁状突软骨属纤维软骨。     

下颌骨髁状突即刻再植的实验研究

为髁状突即刻再植的临床应用提供理论依据。方法　以日本大耳白兔为实验对象 ,切下右侧髁状突后行即刻再植术。左侧作为对照。术后分期处死动物 ,观察骨的愈合、髁状突及关节盘形态和组织学的改变。结果　再植髁状突骨愈合良好。再植髁状突早期有异常的形态学的改变 ,其生长发育受到一定的影响 ,但无关节粘连和强直 ,所有动物可行使正常的咀嚼功能。结论　髁状突即刻再植术可选择性地用于颞下颌关节重建。     

髁状突骨软骨瘤3例

髁状突骨软骨瘤３例孟庆江，吴小英，王建民第四军医大学口腔医学院影像科，郑州市口腔医院骨软骨瘤发生于髁状突者极其少见．现将我院收治的３例，报告如下：ｌ！ｌ＄床资料例１，女，４８岁．右颔部跳痛５年，耳屏前疼痛加重１年，查：右耳屏前触及ＺＣｌｌｌＸＩ．５Ｃ...     

TGF—β1在不同发育阶段胎儿髁突软骨中的表达

目的：研究β转化生长因子－1（TGF－β1）在胎儿髁突软骨中表达,探讨该因子在软骨发育中的作用。方法：30例13－33周胎儿分为A、B、C和D四组,应用HE染色和免疫组化S－P法观察髁突软骨TGF－β1的表达。结果：TGF－β1在所观察各组髁突软骨各层中均有表达,成软骨细胞 层表达最强,主要在胞浆。TGF－β1积分光密度在上、中、下三层之间 存在差异（P＜0．05）。平均灰度和平均光密度在不同胎龄组间存在差异（P＜0．05）。A组与B组、A组与C组、B组与D组、C组与D组之间有显著性差异。结论：在髁突软骨不同发育时间、不同分化阶段TGF－β1的表达水平不同。     

胎儿颞下颌关节髁状突软骨的凝集素亲和组化研究

作者应用凝集素亲和组化法对４３例１３周至３８周的髁状突软骨进行研究。目的是观察胎儿ＣＭＣ各部位的特异性糖基及其随胎龄增长的变化。结果显示：ＣｏｎＡ、ＷＧＡ、ＲＣＡ、ＰＳＡ、ＢＳＬ对该组织有反应。ＣｏｎＡ、ＷＧＡ的反应见于整个胎儿期。ＲＣＡ、ＰＳＡ在１８周出现反应。ＢＳＬ在２２周出现反应，后三者反应均较弱。随着胎龄增长，ＣｏｎＡ、ＰＮＡ、ＢＳＬ等在ＣＭＣ不同部位的凝集素结合指数具有显著性或高度显著性     

髁状突骨软骨瘤病1例

目的为偏[牙合]畸形的原因提供一个新的诊断思路。方法报道1例髁状突骨软骨瘤病例,并回顾相关文献。结果1例50岁男性髁状突软骨瘤患者,术前CT检查明确病变部位及大小,全麻下切除病变骨并进行颞下颌关节重建,术后进行颌间牵引,咬合关系恢复良好。结论对状突骨软骨瘤,为避免复发及恶变,须作肿物切除术,如肿物与髁突粘连,须作髁突切除术及颞下颌关节重建,恢复患者的咬合关系。     

TGF-β_1在不同发育阶段胎儿髁突软骨中的表达

目的 :研究β转化生长因子 - 1(TGF - β1)在胎儿髁突软骨中表达 ,探讨该因子在软骨发育中的作用。方法 :30例 13～ 33周胎儿分为A、B、C和D四组 ,应用HE染色和免疫组化S -P法观察髁突软骨TGF - β1的表达。结果 :TGF - β1在所观察各组髁突软骨各层中均有表达 ,成软骨细胞层表达最强 ,主要在胞浆。TGF - β1积分光密度在上、中、下三层之间存在差异 (P <0 .0 5 )。平均灰度和平均光密度在不同胎龄组间存在差异 (P <0 .0 5 )。A组与B组、A组与C组、B组与D组、C组与D组之间有显著性差异。结论 :在髁突软骨不同发育时间、不同分化阶段TGF - β1的表达水平不同。     

Cell fate mediators Notch and Twist in mouse mandibular condylar cartilage

Objective

The objectives of this study were to examine if Twist and Notch 1 are present in the mandibular condylar cartilage (MCC) and whether their gene expression can be altered by exogenous FGF-2 and TGF-β2.

Design

Half-heads from CD-1 mice pups harvested at embryonic day 17 (E17) were fixed, decalcified, and sectioned in the sagittal plane for immunohistochemical detection of Notch and Twist using confocal microscopy. Other mandibular condyles and adjacent ramus from E17 mice were cultured in serum-free DMEM containing 0, 3, or 30 ng/mL of FGF-2 (10–12 condyles per treatment group). This experimental design was repeated with medium containing 0, 3, or 30 ng/mL of TGF-β2. After 3 days of culture, the pooled RNA from each group was extracted for examination of Notch and Twist gene expression using quantitative real-time RT-PCR.

Results

Immunohistochemical examination revealed that Notch and Twist were localized to the prechondroblastic and upper chondroblastic layers of the cartilage. Exogenous FGF-2 up-regulated Notch 1, Twist 1 and Twist 2 gene expression in MCC explants from E17 mice, whilst TGF-β2 had the opposite effect.

Conclusions

The gene expression data demonstrate that MCC explants are sensitive to growth factors known to affect Notch and Twist in other tissues. The subset of cells in which Twist and Notch immunoreactivity was found is suggestive of a role for FGF-2 and TGF-β2 as regulators of cell differentiation of the bipotent MCC cell population, consistent with the role of Notch and Twist as downstream mediators of these growth factors in other tissues.     

雌二醇浓度对大鼠髁突软骨细胞中雌激素受体mRNA表达的影响

目的：探讨雌二醇(estradiol,E2)对体外培养的髁突软骨细胞雌激素受体(estrogen recerptor,ER)基因表达的影响。方法：体外培养大鼠髁突软骨细胞,分别加入浓度为10-12、10-9、10-6、10-3 mmol/L的17β E2 24 h,实时定量PCR法检测所培养的髁突软骨细胞 ERα、ERβmRNA的表达。采用SPSS10.0软件包对结果进行统计学分析。结果：ERα和ERβ在体外培养的髁突软骨细胞中均有表达,17β E2能够上调ERα的基因表达,同时下调ERβ表达。在10-9 mmol/L的17β E2作用下,上调ERα基因表达最为明显。结论：E2浓度的改变可上调ERα的表达并下调ERβ的表达,在生理范围的雌激素浓度下,E2上调ERα基因表达的作用最为明显。     

髁突软骨细胞分离及体外快速扩增

目的 探索在短期内获得大量成活率高、分化良好的下颌髁突软骨（ｍａｎｄｉｂｕｌａｒ ｃｏｎｄｙｌａｒ ｃａｒｔｉｌａｇｅ,ＭＣＣ）方法 采用细胞工程技术进行兔ＭＣＣ细胞的Ｃｙｔｏｄｅｘ－３微载体培养,应用先进的环境挪描电镜技术对培养ＭＣＣ细胞在微载体地面的生长方式进行了动态观察。结果 ＭＣＣ细胞可快速贴附于Ｃｙｔｏｄｅｘ－３微载体表面,但其 展相对较慢。细胞 展后生长加速,到培养后期,细胞密度可达最     

咀嚼负荷对幼兔髁突软骨细胞BrdU标记影响的研究

目的 探讨咀嚼负荷对幼兔髁突软骨发育及软骨细胞中BrdU标记的影响。方法 出生10 d龄的32只幼兔,随机分为喂食固体硬饲料组和喂食粉末软饲料组。连续2周每天每只腹腔注射BrdU （50 mg/kg）,在2、4、6、8周时每组处死4只幼兔,HE观察组织形态学变化测量软硬组髁突厚度变化,免疫组化检测BrdU表达。结果 髁突软骨前部厚度硬食组明显高于软食组,在中部无明显差异,髁突软骨后部厚度软食组高于硬食组。BrdU免疫组化染色显示,发育期髁突软骨各层及软骨下骨骨髓腔内均有BrdU阳性标记,前部的增殖层表达最显著。第2周,硬食组在前、中、后3个部位的BrdU阳性率都高于软食组;第6周,软食组的中、后部位的阳性率高于硬食组;第8周,软硬组均检测不到阳性细胞。结论 软食组在低咀嚼力刺激下,幼兔髁突软骨细胞增殖启动较慢。适当的咀嚼压力能促进髁突软骨细胞的增殖,同时幼兔发育期的髁突生长还受到基因等内环境因素影响。     

Influence of growth hormone on the mandibular condylar cartilage of rats

Growth hormone (GH) stimulates mandibular growth but its effect on the mandibular condylar cartilage is not well understood. OBJECTIVE: This study was designed to understand the influence of GH on mitotic activity and on chondrocytes maturation. The effect of GH on cartilage thickness was also determined. DESIGN: An animal model witt differences in GH status was determined by comparing mutant Lewis dwarf rats with reduced pituitary GH synthesis (dwarf), with normal rats and dwarf animals treated with GH. Six dwarf rats were injected with GH for 6 days, while other six normal rats and six dwarf rats composed other two groups. Mandibular condylar tissues were processed and stained for Herovici's stain and immunohistochemistry for proliferating cell nuclear antigen (PCNA) and alkaline phosphatase (ALP). Measurements of cartilage thickness as well as the numbers of immunopositive cells for each antibody were analysed by one-way analysis of variance. RESULTS: Cartilage thickness was significantly reduced in the dwarf animals treated with GH. PCNA expression was significant lower in the dwarf rats, but significantly increased when these animals were treated with GH. ALP expression was significant higher in the dwarf animals, while it was significantly reduced in the dwarf animals treated with GH. CONCLUSIONS: The results from this study showed that GH stimulates mitotic activity and delays cartilage cells maturation in the mandibular condyle. This effect at the cellular level may produce changes in the cartilage thickness.     

Origin of mandibular condylar cartilage in mice,rats, and humans: Periosteum or separate blastema?

ObjectiveTo investigate if mandibular condylar cartilage is derived from the periosteum of the ossifying mandible or from a separate, programmed blastema.Materials and methodsFetal mice at E14.0–16.0, fetal rats at E16.0–18.0, and human embryos at 9 and 10 wks of gestation were used. The initial formation of rat condylar cartilage was investigated by using serial sections and enzyme-histochemistry to detect alkaline phosphatase activity. Histological observations of serial sections of human fetuses as well as 3D-reconstruction models were also analyzed. The expression of collagen type mRNA in developing rat condylar cartilage was directly compared with that in mice by performing in situ hybridization.ResultsAn anlage of the rat condylar process (condylar anlage) was clearly identified in the posterior position of the ossifying mandible and was continuous with it at E16.0. Newly formed rat condylar cartilage was observed at E16.5 and was continuous with the ossifying mandible. Mesenchymal cells in the condylar anlage at E16.0 showed alkaline phosphatase activity and chondrocytes in the newly formed condylar cartilage also showed enzymatic activity. Thus, rat mandibular condylar cartilage that derives from alkaline phosphatase-positive periosteum-like cells is continuous with the ossifying mandible, as previously demonstrated in mice, but rapid differentiation into hypertrophic chondrocytes in rats is not remarkable compared to that in mice. The condylar anlage and the newly formed cartilage were also continuous with the ossifying mandible in human embryos.ConclusionsMammalian mandibular condylar cartilage derives from the periosteum of the ossifying mandible in mice, rats, and humans.     

Incisor disocclusion in rats affects mandibular condylar cartilage at the cellular level

The effect of altered occlusion on the mandibular condylar cartilage remains unclear. OBJECTIVE: This study investigated the effect of unilateral incisor disocclusion on cartilage thickness, on mitotic activity and on chondrocytes maturation and differentiation in the mandibular condylar cartilage of rats. DESIGN: The upper and lower left incisors were trimmed 2mm every second day in five rats. In other five rats, the incisor occlusion was not altered. Condylar tissues from both sides of each mandible were processed and stained for Herovici's stain and immunohistochemistry for bromodeoxyuridine (BrdU), transforming growth factor-beta1 (TGF-beta1), alkaline phosphatase (ALP) and osteocalcin (OCN). Measurements of cartilage thickness and the numbers of immunopositive cells for each antibody were analysed by one-way analysis of variance (ANOVA). RESULTS: No significant differences were observed in cartilage thickness after 7 days of unilateral incisor disocclusion. However, the numbers of immunopositive cells for BrdU as a marker of DNA synthesising cells, TGF-beta1 as a marker of chondrocytes differentiation, and ALP and OCN as markers of chondrocytes maturation, were significant higher in the cartilage cells on both sides when incisor occlusion was unilaterally altered. Interestingly, alkaline phosphatase was highly expressed on the condylar side of incisor disocclusion, whereas osteocalcin was highly expressed on the side opposite to the incisor disocclusion. CONCLUSIONS: It is demonstrated that after 7 days, unilateral incisor disocclusion affects the mandibular condylar cartilage at the cellular level by increasing the mitotic activity and by accelerating chondrocytes maturation. Chondrocytes maturation appears more accelerated on the side opposite to incisor disocclusion.     

不同静压力对新生SD大鼠髁突软骨细胞增殖与凋亡的影响

目的：探讨不同静压力对髁突软骨细胞增殖与凋亡的影响。方法：对培养到第3代新生SD大鼠髁突软骨细胞加载0、12、24、36kPa静压力1h后立即收集样本，用流式细胞仪检测细胞凋亡与增殖指数的变化。结果：随着压力的增加（0、12、24、36kPa），除24kPa外，细胞增殖指数和凋亡指数在加力结束时（0h）均减少（P〈0．05），其中，细胞增殖指数在36kPa加力结束时减幅最大，细胞凋亡指数则在12kPa加力结束时减幅最大。结论：在0、12、24、36kPa力值范围内，软骨细胞增殖、凋亡与应力值存在一定的关系，但这并非是简单的线性关系。     

人髁突软骨细胞培养及细胞库建立

目的　建立生物学性状稳定的髁突软骨细胞库 ,为颞下颌关节髁突软骨缺损及关节盘的生物性修复奠定基础。方法　髁突软骨取自因母体健康原因需终止妊娠的人胚胎 ,经机械分离及胰蛋白酶、胶原酶联合消化获得 ,应用微载体培养技术进行髁突软骨细胞的体外扩增 ,采用液氮深低温保存细胞 ,并定期 (2周、1个月 )对复苏软骨细胞生物学特性鉴定。结果　微载体培养技术可在短期内获得大量的、高成活率的髁突软骨细胞。经液氮冻存的软骨细胞在细胞增殖动力学、表型特征及细胞代谢方面无显著变化 ,基本上保持了原代培养软骨细胞的生物学特性。结论　成功的建立了髁突软骨细胞库 ,可为应用组织工程技术修复关节软骨缺损及重建关节盘的研究提供良好的供体细胞