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991.
For the purpose of corneal regenerative medicine, we fabricated human corneal endothelial cell sheets on temperature-responsive dishes, which could be non-invasively harvested as intact, transplantable sheets by simply reducing the culture temperature. Cells demonstrated hexagonal cell shape with numerous microvilli and cilia, and also exhibited abundant cytoplasmic organelles similar to these cells in vivo. Immunofluorescence for type IV collagen and fibronectin revealed that abundant extracellular matrix (ECM) was deposited on the basal surface throughout culture, and the deposited ECM was harvested along with the cell sheets by reducing culture temperature to 20 degrees C. Faint ECM remnants were observed on the dish surfaces after cell sheet detachment. Immunofluorescence for ZO-1 showed that tight junctions were established between cells, and immunoblotting indicated that intact ZO-1 was maintained during cell sheet harvest, while conventional proteolytic cell harvest methods resulted in the degradation of ZO-1. These results suggest that these transplantable corneal endothelial cell sheets can be applied to treat patients with damaged corneas.  相似文献   
992.
993.
The centromere is a chromatin structure essential for correct segregation of sister chromatids, and defects in this region often lead to aneuploidy and cancer. We have previously reported purification of the interphase centromere complex (ICEN) from HeLa cells, and have demonstrated the presence of 40 proteins (ICEN1-40), along with CENP-A, -B, -C, -H and hMis6, by proteomic analysis. Here we report analysis of seven ICEN components with unknown function. Centromere localization of EGFP-tagged ICEN22, 24, 32, 33, 36, 37 and 39 was observed in transformant cells. Depletion of each of these proteins by short RNA interference produced abnormal metaphase cells carrying misaligned chromosomes and also produced cells containing aneuploid chromosomes, implying that these ICEN proteins take part in kinetochore functions. Interestingly, in the ICEN22, 32, 33, 37 or 39 siRNA-transfected cells, CENP-H and hMis6 signals disappeared from all the centromeres in abnormal mitotic cells containing misaligned chromosomes. These results suggest that the seven components of the ICEN complex are predominantly localized at the centromeres and are required for kinetochore function perhaps through or not through loading of CENP-H and hMis6 onto the centromere.  相似文献   
994.
The balance between CD4+ T helper (Th1) lymphocytes producing interferon-γ or Interleukin-4 (Th2) in the lungs may vary among diseases and during the progression of interstitial pneumonia (IP). Both idiopathic pulmonary fibrosis (IPF) and collagen vascular diseases (CVD) are associated with IP, but the clinical course and the response to treatment are different. Since Th1 or Th2 modulating drugs have been proven to alter the lymphocyte balance in vitro, it is important to elucidate the Th1/Th2 profile in patients with active IP. Bronchoalveolar lavage (BAL) was performed in patients who had IPF (n = 12) or CVD (n = 12) with IP, as well as in patients who had bronchoectasis and bronchopneumonia (n = 12). The CVD patients had rheumatoid arthritis (n = 6), Sjogren's syndrome (n = 2), dermatomyositis (n = 1), progressive systemic sclerosis (n = 2), and CREST syndrome (n = 1) as the underlying diseases. IP activity was evaluated by measuring serum KL-6, which is a clinically useful indicator for IP. The Th1/ Th2 balance and the CD4+/CD8+ ratio were determined for lymphocytes obtained from BAL by flow cytometric analysis. In IPF patients, the CD4+/CD8+ ratio was lower than in CVD patients. IPF patients showed Th2 dominance and CVD patients showed Th1 dominance when IP was active as evaluated by the serum KL-6 level. These data indicated that the Th1/Th2 balance of CD4+ T cells in the BAL differs between active IPF and CVD, even though KL-6 is elevated in both diseases. Therefore, the Th1/Th2 profile should be investigated to determine the use of Th1/Th2 modulator therapy for active IP with elevation of KL-6.  相似文献   
995.
目的观察谷氨酸脱羧酶67-绿色荧光蛋白(GAD67-GFP)基因敲入小鼠三叉神经尾侧亚核(Vc)浅层内,表达GFP的GABA能神经元的分布及其与小白蛋白(PV)的共存。方法分别运用原位分子杂交与免疫组织化学相结合;GFP与神经元标记物——神经元核蛋白(NeuN)或PV免疫荧光染色相结合的双重标记方法,在光学显微镜和激光共聚焦显微镜下进行观察。结果1.Vc浅层内90%以上的GFP阳性神经元同时表达GAD67 mRNA,而几乎所有表达GAD67 mRNA的阳性神经元都呈GFP阳性;2.GFP阳性神经元主要分布于Vc的Ⅰ-Ⅱ层内,细胞较小,尤其在Ⅱ层内可见大量密集分布的GFP阳性细胞和突起。GFP阳性神经元分别占Ⅰ、Ⅱ层内NeuN阳性神经元总数的19.4%和24.3%;3.GFP/PV双标神经元主要分布于Vc的Ⅰ-Ⅱ层,这些双标神经元大约占PV阳性神经元的62.4%,占GFP阳性神经元的12.8%。结论在Vc表达GFP的GABA能神经元主要密集分布于与外周伤害性信息传递关系密切的板层内,且大部分PV样阳性神经元属于GABA能神经元。  相似文献   
996.
BACKGROUND: The loop-mediated isothermal amplification (LAMP) method is a novel technique for the amplification of specific DNA sequences. OBJECTIVES: To establish the LAMP method for amplifying Epstein-Barr virus (EBV) DNA and to examine its reliability for the detection of EBV DNA in clinical specimens. STUDY DESIGN: Sera from 108 patients, who were initially suspected of primary EBV infection, were tested by the EBV LAMP method, and the results were compared with those of the real-time PCR assay. Serological examination was regarded as the standard diagnostic method. RESULTS: To diagnose primary EBV infection, the sensitivity of LAMP was 86.4% and the specificity was 100%. The sensitivity of the real-time PCR assay was 84.1% and the specificity was 98.4%. Longitudinal analysis showed that the detection rate of EBV DNA in serum by the LAMP method decreased with time in accordance with the decrease of the EBV load. EBV DNA could not be detected in serum 40 days after onset of symptoms. CONCLUSIONS: These results indicate that the sensitivity and specificity of the LAMP method are comparable to those of real-time PCR and that detecting EBV DNA in serum by this method is potentially useful for diagnosing primary EBV infection.  相似文献   
997.
In order to evaluate the contribution of FBN1, FBN2, TGFBR1, and TGFBR2 mutations to the Marfan syndrome (MFS) phenotype, the four genes were analyzed by direct sequencing in 49 patients with MFS or suspected MFS as a cohort study. A total of 27 FBN1 mutations (22 novel) in 27 patients (55%, 27/49), 1 novel TGFBR1 mutation in 1 (2%, 1/49), and 2 recurrent TGFBR2 mutations in 2 (4%, 2/49) were identified. No FBN2 mutation was found. Three patients with either TGFBR1 or TGFBR2 abnormality did not fulfill the Ghent criteria, but expressed some overlapping features of MFS and Loeys-Dietz syndrome (LDS). In the remaining 19 patients, either of the genes did not show any abnormalities. This study indicated that FBN1 mutations were predominant in MFS but TGFBRs defects may account for approximately 5-10% of patients with the syndrome.  相似文献   
998.
Post-operative adhesions often cause severe complications such as bowel obstruction and abdominopelvic pain. Previously, we reported that transplantation of a mesothelial cell sheet is effective for preventing adhesion in rat model. We also proposed a new technique for harvesting autologous mesothelial cells from tunica vaginalis without intra-abdominal maneuvers. In this study, we examined whether an autologous mesothelial cell sheet can prevent post-operative peritoneal adhesions in a canine adhesion model. Mesothelial cells were isolated from the tunica vaginalis of male beagles. Isolated cells were cultured on fibrin gel. We named this construct the "mesothelial cell sheet." Animals underwent surgery to induce peritoneal adhesion formation and were then transplanted with the mesothelial cell sheets (sheet group, n = 4), fibrin gel (fibrin group, n = 4), or no materials (sham group, n = 4). Four weeks after the transplantation, we evaluated adhesion formation and scored adhesion levels. The abdominal wall transplanted with the mesothelial cell sheet was covered with mesothelium. The total adhesion score of the sheet group was significantly lower than that of the fibrin group and the sham group. These results indicated that transplantation of an autologous mesothelial cell sheet is effective for preventing post-operative adhesion formation in the canine adhesion model. Our mesothelial cell sheet has the potential to be a powerful adhesion prophylactic material in surgery.  相似文献   
999.
We previously reported that angiotensin II type 1 receptor (AT1R) blockade attenuates renal inflammation/fibrogenesis in immune-mediated glomerulonephritis via angiotensin II type 2 receptor (AT2R). In the present study, further in vivo experiments revealed that AT2R was expressed in tubular epithelial cells of nephritic kidneys in mice, and feedback activation of the renin-angiotensin system during AT1R blockade significantly reduced p-ERK, but not intranuclear nuclear factor-kappaB, levels via AT2R. This led to reduction in mRNA levels of the proinflammatory mediator monocyte chemoattractant protein-1 and overall interstitial inflammation and subsequent fibrogenesis. Specific blockade of ERK expression in tubular epithelium by anti-sense oligodeoxynucleotides also attenuated interstitial inflammation, mimicking the anti-inflammatory action of AT2R in nephritic kidneys. Alternatively, we succeeded in confirming such an AT(2)R function by demonstrating that AT1R blockade did not confer renoprotection in nephritic, AT2R gene-deficient mice. Additional in vitro experiments revealed that AT2R activation did not affect nuclear factor-kappaB activation by tumor necrosis factor-alpha in cultured tubular epithelial cells, although it inhibited ERK phosphorylation, which reduced monocyte chemoattractant protein-1 mRNA levels. These results suggest that feedback activation of AT2Rs in tubular epithelium of nephritic kidneys plays an important role in attenuating interstitial inflammation.  相似文献   
1000.
For cartilage reconstruction, it is still difficult to obtain a sufficient volume of cartilage and to maintain its functional phenotype for a long period. Utilizing tissue stem cells is one approach to overcome such difficulties. We show here the presence of cartilage progenitor cells in the ear perichondrium of adult rabbits by 5-bromo-2'-deoxyuridine labeling, clonogenicity, and differentiation analyses. Long-term label-retaining cells were demonstrated in the perichondrium. Cells from the perichondrium, that is, perichondrocytes were mechanically isolated using a raspatory and maintained in D-MEM/F-12 medium with 10% FCS. They proliferated more vigorously than chondrocytes from the cartilage. Perichondrocytes could differentiate into adipocytes as well as osteocytes in differentiation induction medium. For cartilage reconstruction in vivo, perichondrocytes were seeded on collagen sponge scaffolds and implanted in nude mice. After 4 weeks, the composites with perichondrocytes generated the same weight of cartilaginous tissue as those with chondrocytes. They produced glycosaminoglycan and type II collagen as shown by RT-PCR and immunohistochemical examination. On the contrary, rabbit bone marrow mesenchymal stem cells used as control could regenerate significantly smaller cartilage than perichondrocytes in the implant study. Based on these findings, we propose that the perichondrium containing tissue progenitor cells is one of the potential candidates for use in reconstructing cartilage and new therapeutic modalities.  相似文献   
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