力竭运动大鼠心室肌蛋白质组表达特征

目的:采用蛋白质组学技术,建立安静和递增运动负荷训练后力竭大鼠心室肌蛋白质组的差异性表达谱,初步筛选出心室肌对力竭运动产生反应的目标蛋白质。方法:实验于2007-03在湖南师范大学生命科学学院蛋白质化学与蛋白质组学国家教育部重点实验室和省级运动人体科学实验室完成。①实验分组:10只SD雄性大鼠随机分为对照组和运动组,每组5只。②实验方法:运动组经过7周的大强度递增运动负荷训练后(最后一次力竭),对两组心室肌组织的全蛋白进行双向凝胶电泳分离。结果:经图像分析,在运动组的电泳图谱上共展现蛋白质点(338±17)个,对照组展现蛋白质点(352±17)个。运动后差异表达的蛋白质点共有99个。对其中差异表达的9个蛋白质点进行质谱鉴定,共鉴定出7个蛋白质,Stress-70protein,NADH-ubiquinone oxidoreductase Mr75000subnunit,Long-chain specific acyl-CoA dehydrogenase,Tropomyosin-1alphachain在运动后"缺失",Nitrilase family,member2在运动后表达上调在5倍以上,一个相对分子质量为21000的未知蛋白在运动后表达下调在5倍以上,另外有两个点经鉴定均为Myosin-6,在运动后表达量相反。这些蛋白质属于收缩蛋白、能量代谢酶、分子伴侣等。结论:递增运动负荷训练后力竭时,大鼠心室肌蛋白质组明显地发生了反应。运动后"缺失"和下调的蛋白质点与心肌收缩的调控和能量代谢的方式转变以及细胞的应激反应有关,其中,成功筛选出6种在运动医学领域尚未涉足的、具有运动应激特点的目标蛋白质。     

Soluble Plasmodium falciparum antigens contain carbohydrate moieties important for immune reactivity.

The importance of carbohydrate moieties for the antigenicity of purified soluble Plasmodium falciparum antigens from the asexual blood stage was tested. Digestion of the soluble antigens with alpha-D-galactosidase clearly affected the ability of the antigen to react with malaria-immune sera from different geographical origins in crossed immunoelectrophoresis and immunoblotting. Antigens of 220, 180, 80, and 74 kilodaltons were affected by the enzyme treatment. Furthermore, the enzyme digestion reduced the ability of the purified soluble antigen to stimulate lymphocytes from malaria-immune donors. The results might have important implications for the strategy of developing a malaria vaccine.     

Highly Polymorphic Domains of the Human Serum Amyloid A (SAA) Gene GSAA1

The DNA of the human serum amyloid A (SAA) gene GSAA1 contains several repetitive regions within its introns. We have studied length variations at one such region in the 2nd intron by selective amplification using the polymerase chain reaction (PCR) and defined oligonucleotide primers. The lengths of the repetitive regions frequently differ between individual chromosomes and can be transmitted as Mendelian markers, making them useful for genetic linkage analysis.     

Evaluation of maternal plasma creatine kinase activity as a marker of abnormal early pregnancy

We have tested the value of maternal plasma creatine kinase activity for diagnosing ectopic pregnancies obtained after in-vitro fertilization and embryo transfer. Plasma creatine kinase was assayed in 57 patients: 20 normal, 23 miscarriages and 14 ectopic pregnancies, for a total of 240 samples. All values were in the lower part of the normal range except only one in a miscarrying patient. A statistically significant difference was observed for a cut-off value of 45 IU/l between normal and ectopic pregnancies. However, for this cut-off point, the measurement of plasma creatine kinase activity had a sensitivity of 0.50 and a specificity of 0.76 for the diagnosis of ectopic pregnancy. The positive predictive value was 0.69. Creatine kinase activity measurements are thus of no practical value in this particular population, in which an early and specific marker of ectopic implantation would be of paramount interest. The association of human chorionic gonadotrophin (HCG) determinations and ultrasound scanning of the pelvis still remain the best paraclinical support for an early diagnosis of ectopic implantation.      

Clinical and genetic analysis of Korean patients with Marfan syndrome: possible ethnic differences in clinical manifestation

Yoo E‐H, Woo H, Ki C‐S, Lee HJ, Kim D‐K, Kang I‐S, Park P, Sung K, Lee CS, Chung T‐Y, Moon JR, Han H, Lee S‐T, Kim J‐W. Clinical and genetic analysis of Korean patients with Marfan syndrome: possible ethnic differences in clinical manifestation. Marfan syndrome (MFS) is an autosomal dominant disorder of the fibrous connective tissue caused by mutations in the fibrillin‐1 (FBN1) gene. Although clinical and genetic analyses have been performed in various populations, there have been few studies in Korea. The aim of this study was to investigate the clinical characteristics and genetic background of Korean patients with MFS. In 39 Korean patients with MFS who met the Ghent criteria, the most common clinical finding was aortic dilatation and/or dissection (94.9%), whereas only 35.9% of patients had ectopia lentis. The majority of MFS patients had fewer than four of the skeletal findings required to fulfill the major skeletal Ghent criterion for MFS. Only 21% of Korean patients had major skeletal abnormalities and most cases showed only minor skeletal involvement. FBN1 gene mutations were detected in 35 out of 39 patients (89.7%), which is similar to rates presented in the previous reports. These results suggest that some clinical features in Korean patients with MFS differed from those reported in Western MFS patients.     

Effect of platform switching on peri-implant bone levels: a randomized clinical trial

Objective: The concept of platform switching has been introduced to implant dentistry based on observations of reduced peri‐implant bone loss. However, randomized clinical trials are still lacking. This study aimed to test the hypothesis that platform switching has a positive impact on crestal bone‐level changes. Material and methods: Two implants with diameters of 4 mm were inserted epicrestally into one side of the posterior mandibles of 25 subjects. After 3 months of submerged healing, the reentry surgery was performed. On the randomly placed test implant, an abutment 3.3 mm in diameter was mounted, resulting in a horizontal circular step of 0.35 mm (platform switching). The control implant was straight, with an abutment 4 mm in diameter. Single‐tooth crowns were cemented provisionally. All patients were monitored at short intervals over the course of 1 year. Standardized radiographs and microbiological samples from the implants' inner spaces were obtained at baseline (implant surgery), and after 3, 4, and 12 months. Results: After 1 year, the mean radiographic vertical bone loss at the test implants was 0.53±0.35 mm and at the control implants, it was 0.58±0.55 mm. The mean intraindividual difference was 0.05±0.56 mm, which is significantly <0.35 mm (P=0.0093, post hoc power 79.9%). The crestal bone‐level changes depended on time (P<0.001), but not on platform switching (P=0.4). The implants' internal spaces were contaminated by bacteria, with no significant differences in the total counts between the test and the control at any time point (P=0.98). Conclusions: The present randomized clinical trial could not confirm the hypothesis of a reduced peri‐implant bone loss at implants restored according to the concept of platform switching. To cite this article:
Enkling N, Jöhren P, Klimberg V, Bayer S, Mericske‐Stern R, Jepsen S. Effect of platform switching on peri‐implant bone levels: a randomized clinical trial.
Clin. Oral Impl. Res. 22 , 2011; 1185–1192.
doi: 10.1111/j.1600‐0501.2010.02090.x     

Assessment of the involvement of the macrophage migration inhibitory factor–glucocorticoid regulatory dyad in the expression of matrix metalloproteinase‐2 during periodontitis

Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine and counter‐regulator of endogenous glucocorticoids (GCs). It is implicated in acute and chronic inflammatory diseases. This study investigated the role of the MIF–GC regulatory dyad in the expression and release of matrix metalloproteinase‐2 (MMP‐2) during periodontitis, in vivo and in vitro. In a Mif‐knockout (KO) mouse model of ligature‐induced periodontitis, gingival tissues and blood were collected and analysed for levels of interleukin‐6 (IL‐6), MIF, MMP‐2, and corticosterone. In addition, human gingival fibroblasts (HGFs) were tested for production of IL‐6 and MMP‐2 after stimulation with hydrocortisone (HC), MIF, tumour necrosis factor‐alpha (TNF‐α), or Fusobacterium nucleatum, a pathogen known to elicit immune responses during periodontitis. Wild‐type (WT) mice showed a local and systemic increase of MIF levels during inflammation, which was confirmed by increased local IL‐6 concentrations. Systemic GC levels were reduced in WT and Mif‐KO mice during inflammation, with overall lower concentrations in Mif‐KO mice. In vivo and in vitro, MMP‐2 production was not dependent on MIF or inflammatory stimuli, but was inhibited by HC. Therefore, MIF does not appear to stimulate expression of MMP‐2 in the gingival tissues, whereas GC upregulates MIF and downregulates MMP‐2. Our findings further suggest that MIF may regulate systemic GC levels.