核因子-κB p65在小鼠耳蜗中的表达

目的探讨核因子-κB(nuclear factor-kappa B,NF-κB)在耳蜗的表达情况。方法24只小鼠随机平均分为4组,其中2组分别连续3d和7d于皮下注射卡那霉素(kanamycin,KA),一组鼓室注射脂多糖(lipopolysac-charides LPS),另一组皮下注射等量生理盐水7d作为对照,用多克隆兔抗体NF-κB p65免疫组织化学等染色,观察NF-κB p65在小鼠耳蜗的表达。结果NF-κB p65主要定位在耳蜗的螺旋缘、盖膜、血管纹、螺旋韧带、螺旋神经节和神经纤维。整个耳蜗各回均可观察到免疫反应,而螺旋韧带、盖膜、螺旋突、螺旋神经节和神经纤维均可观察到较强的NF-κB p65免疫反应,Corti器的免疫反应比上述结构要弱一些。Corti器的内、外毛细胞,内、外柱细胞,Deiter细胞和Claudious细胞均可观察到NF-κB p65的免疫反应,这些免疫反应在内沟细胞、Hensen细胞和Claudious细胞显示较弱,而在螺旋神经节较强,内、外毛细胞核未见免疫反应。省去一抗的对照染色未观察到NF-κB p65的阳性反应。用脂多糖和卡那霉素处理的小鼠耳蜗NF-κB p65的免疫反应与注射正常生理盐水的小鼠耳蜗有显著性差异,而注射脂多糖和卡那霉素3d和7d NF-κB p65的免疫反应无差异。结论注射脂多糖和卡那霉素可使NF-κB p65在耳蜗的表达增强。     

高脂血症小鼠模型耳蜗中核因子-κB p65的表达

目的:探讨高脂血症对小鼠耳蜗的影响。方法:20只昆明种小鼠随机平均分为2组,其中1组建立高脂血症模型,另1组作为对照,6周后用多克隆兔抗NF-κB p65免疫组织化学染色,观察NF-κB p65在高脂血症小鼠耳蜗中的表达,并检测小鼠ABR反应阈。结果:在高脂血症小鼠耳蜗中,NF-κB p65主要定位在Corti器、盖膜、血管纹、螺旋韧带、螺旋神经节及其神经纤维,高脂血症小鼠耳蜗NF-κB p65的免疫反应与对照组比较显著增强。高脂血症模型组小鼠ABR反应阈与对照组比较明显增高,差异有统计学意义(P<0.01)。结论:高脂血症可使小鼠耳蜗NF-κB p65表达增强,ABR反应阈增高,表明高脂血症可引起小鼠听力损害。     

Survival of Partially Differentiated Mouse Embryonic Stem Cells in the Scala Media of the Guinea Pig Cochlea

The low regenerative capacity of the hair cells of the mammalian inner ear is a major obstacle for functional recovery following sensorineural hearing loss. A potential treatment is to replace damaged tissue by transplantation of stem cells. To test this approach, undifferentiated and partially differentiated mouse embryonic stem (ES) cells were delivered into the scala media of the deafened guinea pig cochlea. Transplanted cells survived in the scala media for a postoperative period of at least nine weeks, evidenced by histochemical and direct fluorescent detection of enhanced green fluorescent protein (EGFP). Transplanted cells were discovered near the spiral ligament and stria vascularis in the endolymph fluid of the scala media. In some cases, cells were observed close to the damaged organ of Corti structure. There was no evidence of significant immunological rejection of the implanted ES cells despite the absence of immunosuppression. Our surgical approach allowed efficient delivery of ES cells to the scala media while preserving the delicate structures of the cochlea. This is the first report of the survival of partially differentiated ES cells in the scala media of the mammalian cochlea, and it provides support for the potential of cell-based therapies for sensorineural hearing impairment.     

实验性微栓塞缺血豚鼠耳蜗cNOS的表达变化

目的 探究一氧化氮（nitricoxide，NO）在一过性微栓塞耳蜗缺血性损伤中的作用。方法 20只豚鼠随机分为实验组和对照组各10只，实验组动物通过磁微粒栓塞造成实验性耳蜗缺血模型；以扫描电镜观察缺血耳蜗听纤毛变化；以免疫组织化学方法观察原生型一氧化氮合酶（constitutive nitric oxide synthase，cNOS）在两组耳蜗的表达变化。结果 实验性耳蜗缺血造成内外毛细胞听纤毛散在的粘结、倒伏或缺失，内毛细胞听纤毛病变明显；内皮型一氧化氮合酶（endothelial NOS，eNOS）表达分布于蜗轴及内侧螺旋板内神经纤维、螺旋神经节、内侧螺旋缘、Corti器细胞及血管纹／螺旋韧带区；神经型一氧化氮合酶（neuron NOS，nNOS）主要分布于蜗轴及内侧螺旋板内神经纤维、螺旋神经节细胞，在Corti器细胞、血管纹细胞及内侧螺旋缘上皮细胞有较弱的表达；实验性缺血组豚鼠耳蜗与正常对照组耳蜗原生型一氧化氮合酶的表达无差异。结论 微栓塞耳蜗缺血引起散在听毛细胞损伤；两种原生型NOS在耳蜗固有表达，分布有交叉，功能存在相互代偿，但未发现因微栓塞缺血而引起变化。     

spontaneous proliferation in organotypic cultures of mouse cochleae

Cells in mammalian cochleae virtually stop proliferation and exit cellular circle before birth. Consequently, hair cells and spiral ganglion neurons destroyed by ototoxic factors cannot be replaced through proliferative regeneration. However, substantial proliferation occurs in organotypic cultures of cochleae from postnatal mice. In the present study, we studied the time course of proliferative growth in cultures of mouse cochlea explants obtained from up to 12 postnatal days. The mitotic nature of this growth was confirmed by bromodeoxyuridine (BrdU) staining and expression of proliferation cell nuclear antigen (PCNA) evaluated with real-time quantitative polymerase chain reaction(RT-PCR). Similar growth time course was found in the cochlear explants of different postnatal ages. The new growth reached its maximum at around 2 days in culture followed by a slow-down, and virtually stopped after 5 days of culture. The possible mechanisms and the significance of this proliferation are discussed.     

喉癌患者多药耐药相关蛋白基因的表达及其临床意义

目的：研究多药耐药相关蛋白基因（ＭＲＰ ｍＲＮＡ）的表达与喉癌患者临床病理特征之间的关系。方法：应用逆转录－多聚酶链反应（ＲＴ－ＰＣＲ）技术,检测了３５例喉癌患者ＭＲＰ ｍＲＮＡ的表达。结果：喉癌组织中ＭＲＰ ｍＲＮＡ阳性表达率为４５．７％（１６／３５）,其阳性表达强度在晚期肿瘤中明显增高（Ｐ〈０．０５）,且与肿瘤颈淋巴结转移明显相关（Ｐ〈０．０１）,结论：ＭＲＰ ｍＲＮＡ在喉癌中的表达,不仅提示     

The Prognostic Role of p16 Expression in Tonsil Cancer Treated by Either Surgery or Radiation

Objectives

Although human papillomavirus (HPV) infection is considered as a favorable prognostic factor in oropharyngeal cancer, the prognosis of HPV-associated tonsil cancer has rarely been studied especially when surgery was the main treatment. In this study, the authors investigated the effect of p16 over-expression (HPV infection) on tonsil cancer prognosis according to the type of treatment, HPV presence by PCR, and expression of p53 and epidermal growth factor receptor (EGFR) by immunohistochemistry (IHC).

Methods

Medical records of 33 tonsil cancer patients were reviewed. Using formalin-fixed and paraffin-embedded tumor specimens, PCR-based genotyping of HPV and IHC of p16, p53 and EGFR were performed. The effects of HPV presence and the expression of IHC markers were analyzed on the recurrence-free survival. Five-year disease-free survival (DFS) rates were evaluated according to p16 expression status.

Results

An over-expression of p16 was observed in 27 (81.9%) out of 33 cases. Surgery-based treatment was provided for 21 (63.6%) patients. There was no association between p16 immunoreactivity and HPV presence, nor with p53 and EGFR expression. Regardless of main treatment modalities, five-year DFS did not differ by p16 expression status (P=0.051). However, over-expression of p16 was associated with a lower recurrence in multivariable analyses (P=0.046).

Conclusion

Regardless of main treatment modalities, an over-expression of p16 (HPV infection) is associated with a lower recurrence in tonsil cancers. However it is not associated with simple HPV presence or p53 and EGFR over-expression.