Increased expression of discoidin domain receptor 2 is linked to the degree of cartilage damage in human knee joints: a potential role in osteoarthritis pathogenesis

OBJECTIVE: To investigate the relationship between increased discoidin domain receptor 2 (DDR-2) expression and cartilage damage in osteoarthritis (OA). METHODS: Full-thickness cartilage tissue samples from 16 human knee joints were obtained and the grade of cartilage damage was evaluated according to the Mankin scale. Expression of DDR-2, matrix metalloproteinase 13 (MMP-13), and MMP-derived type II collagen fragments was visualized immunohistochemically. Moreover, upon stimulation with either type II collagen or gelatin, levels of DDR-2 and MMP-13 messenger RNA (mRNA) in primary human articular chondrocytes were assessed by real-time polymerase chain reaction. RESULTS: Immunohistochemical analysis showed an increase in DDR-2 expression in human articular cartilage, which was correlated with the degree of tissue damage. In parallel, the extent of MMP-13 and type II collagen breakdown products was elevated as a function of increased DDR-2 expression and cartilage damage. Furthermore, in vitro experiments revealed an up-regulation of both DDR-2 and MMP-13 mRNA in human articular chondrocytes after stimulation with type II collagen. CONCLUSION: Our data indicate that 3 factors, DDR-2 expression, MMP-13 expression, and the degree of cartilage damage, are linked, such that DDR-2 promotes tissue catabolism, and tissue degradation promotes DDR-2 up-regulation and activation. Thus, the perpetuation of DDR-2 expression and activation can be seen as a vicious circle that ultimately leads to cartilage destruction in OA.     

Intrathecal baclofen for treatment of spasticity of multiple sclerosis patients

We conducted a retrospective study of the case files of 64 multiple sclerosis (MS) patients presenting severe spasticity, who had received intrathecal (IT) baclofen test injections between 1992 and 2004 in a rehabilitation unit. In almost all cases of our series, IT baclofen was proposed to patients who were no longer able to walk. IT baclofen is a safe and effective treatment to reduce spasticity in MS patients. Despite an advanced stage of the disease at the time of pump placement, the complication rate was low and the efficacy of this treatment was maintained over time.     

Detection of anti-aquaporin-4 autoantibodies in the sera of Chinese neuromyelitis optica patients

In this study, we recruited 10 neuromyelitis optica patients, two multiple sclerosis patients and two myelitis patients. Chinese hamster lung fibroblast (V79) cells transfected with a human aquaporin-4-mCherry fusion protein gene were used to detect anti-aquaporin-4 antibody in neuromyelitis optica patient sera by immunofluorescence. Anti-aquaporin-4 autoantibody was stably detected by immunofluorescence in neuromyelitis optica patient sera exclusively. The sensitivity of the assay for neuromyelitis optica was 90% and the specificity for neuromyelitis optica was 100%. The anti-aquaporin-4 antibody titers in sera were tested with serial dilutions until the signal disappeared. A positive correlation was detected between Expanded Disability Status Scale scores and serum anti-aquaporin-4 antibody titers. The anti-aquaporin-4 antibody assay is highly sensitive and specific in the sera of Chinese neuromyelitis optica patients. Detection of aquaporin-4 autoantibody is important for the diagnosis and treatment of neuromyelitis optica.     

131I-chTNT在荷人肝癌裸鼠动物模型中的定位研究

目的评价１３１Ｉ单克隆抗体ｃｈＴＮＴ与肝肿瘤的亲和性，以了解其用于肝肿瘤定位诊断和导向治疗的可能性。方法荷人肝癌裸鼠动物模型腹腔注射５５５ＭＢｑ１３１ＩｃｈＴＮＴ后１、２、３、５、７天，分别作放射免疫显像，并逐日分组杀死，行组织分布测定，并与１３１Ｉ对照组比较。结果实验组注射标记抗体后１天肿瘤组织清晰显影，并持续显示至实验结束。瘤体内放射性维持相对稳定水平，１３１ＩｃｈＴＮＴ在肝癌组织内的有效半减期为６０±１６天。其他脏器组织放射性浓聚少，并逐渐消失。第７天Ｔ／ＮＴ比值达１０６７。结论１３１ＩｃｈＴＮＴ具有导向肝肿瘤的特性，为用于肝癌放射免疫显像和导向治疗提供了依据。     

应用NCCLS EP10-T2评价国产电解质分析仪

目的 评价国产电解质分析仪以寻求适合国情的钾钠氯测定方法。方法 应用美国临床实验室标准化委员会（ＮＣＣＬＳ）颁布的《定理临床实验室方法初步评价试行准则（ＥＰ１０－Ｔ２）》进行初步评价。结果 除远高于临床决定性水平的高钠高氯外，其余１０项总不精密度均小于我国和美国ＣＬＩＡ８８的允许误差范围。结论 ＡＦＴ－５００Ｂ电解质分析仪性能可靠，适合国情，正确使用将有助于许多临床实验室摆脱困扰。