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1.

Background

Since recent reports have shown that (-)-Epigallocatechin-3-gallate (EGCG) could be used for treating proliferative and inflammatory disorders, we explored its use for the management of corneal chemical burns.

Materials and methods

Initially, EGCG was assayed on the rabbit corneal epithelial cell line RCE1(5T5) to establish the best testing conditions, and to avoid unwanted outcomes in the experimental animals. Then, we studied its effects on cell proliferation, cell cycle progression and cell differentiation. Afterwards, we instilled EGCG in experimental grade II corneal alkali burns in mice, three times a day up to 21 days, and evaluated by slit lamp examination and histological sections of corneal epithelial, corneal endothelial and stromal edema, as well as the presence of inflammatory cells and neovascularization.

Results

EGCG reduced cell growth and led to a decline in the proportion of proliferative cells in a concentration dependent manner. At 10 μM, EGCG promoted cell differentiation, an effect not related with apoptosis or cytotoxicity. When 10 μM EGCG was instilled in corneal alkali burns in mice three times a day up to 21 days, EGCG significantly reduced corneal opacity and neovascularization. The improved clinical appearance of the cornea was associated to a controlled epithelial growth; epithelial morphology was similar to that observed in normal epithelium and contrasted with the hyperproliferative, desquamating epithelium observed in control burn wounds. EGCG reduced corneal, stromal and endothelial edema, and wound inflammation.

Conclusion

This work constitutes the first evidence for the use of EGCG in the acute phase of a corneal alkali burn, representing a possible novel alternative to improve patient outcomes as an add-on therapy.  相似文献   
2.
3.
Many cellular signaling pathways are involved in the development of cancer. Depending on the tumor entity, the nature as well as the mode of activation can differ. Some signaling pathways frequently show changes as all tumor cells have to fulfill some basic requirements such as independence from growth factors or insensitivity against apoptosis. In this review, the possibilities of a tumor to manipulate signaling pathways to reach these goals are exemplified based on an archetypical melanoma cell. In addition, new therapeutic options based on the knowledge of signaling pathways will be discussed.  相似文献   
4.
What is the value of bcl-2 protein detection for histopathologists?   总被引:15,自引:0,他引:15  
  相似文献   
5.
骨外型牙源性钙化上皮瘤1例报告   总被引:2,自引:0,他引:2  
牙源性钙化上皮瘤是一种良性肿瘤,也称Pindborg瘤,可分为骨内型和骨外型2种,主要发生于颌骨内,偶见于颌骨外。本文报告1例发生于口底的牙源性钙化上皮瘤,其临床症状与口底皮样囊肿相似.术后经组织病理学确诊,主要组织病理学特征是嗜酸性环状钙化团块。因其具有局部侵袭性,为避免复发,提倡完整切除肿物。  相似文献   
6.
BACKGROUND: To understand the immunopathological features of oral lichen planus (OLP), we analyzed the expression of chemokines in the epithelial cell layers. Methods: Epithelia from OLP or healthy gingiva were collected by laser microdissection. The chemokine and chemokine receptor expressions in the epithelia were analyzed by DNA microarray. RESULTS: High levels of MIP-3alpha/LARC/CCL20 and its receptor CCR6 were expressed in the lesional epithelia. Furthermore, DC-CK1/CCL18, ELC/CCL19, SDF-1/CXCL12 and CXCR4 expressions were also increased. Immunohistologial analysis showed that high numbers of Langerhans cells (LCs) were present in the epithelia of OLP. Lesional epithelia also expressed high levels of the ligands specific for CXCR3 (e.g. MIG/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11) and CCR5 (e.g. RANTES/CCL5). CONCLUSIONS: Infiltration of LCs is orchestrated by CCR6. Further, LCs residing in the lesional epithelia may be a mature phenotype. Moreover, infiltration of T cells in OLP could be mediated by signaling pathways through CXCR3 and CCR5.  相似文献   
7.
本研究建立了大鼠气管上皮细胞体内-体外转化模型,大鼠气管内滴注苯并芘,三天后处死大鼠,消化气管上皮细胞,接种于无血清完全培养基。细胞形成集落后,换为选择培养基继续培养五周,统计转化率。结果显示,25mg/kg和50mg/kg的苯并芘可诱导大鼠气管上皮细胞转化及微核增加,用同样方法研究了煤焦沥青提取物,结果表明,剂量为8mg/kg和25mg/kg的煤焦沥青提取物能明显诱导大鼠气管上皮细胞转化。  相似文献   
8.
Summary Formation of epithelial tissues in culture so that they become facsimiles in their structure of such tissues in nature requires procedures that comply with several spatial imperatives: a) three-dimensional growth; b) histophysiologic conditions that provide, concurrently, gradients of maturation and of diffusion of metabolites; and c) growth as layers of cells without free edges. Many steps have been required in the evolution of these methods. Two systems are described here in sufficient detail to serve as a manual. Three-dimensional growth of masses of epithelial tissue is accomplished in matrix culture using Gelfoam sponge and collagen-coated cellulose sponge. Radial gradient culture, a recent development, provides conditions that comply with the requirements of histophysiologic gradients and of epithelial tissue growth in layers without interruption in their continuity.  相似文献   
9.
We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described.  相似文献   
10.
Infiltration of CD8(+)TCRalphabeta(+) T-effector populations (CD8 effectors) into graft epithelial compartments has long been recognized as a key lesion in progression of clinical renal allograft rejection. While the afferent phase of allograft immunity is increasingly well-defined, the efferent pathways by which donor-reactive CD8-effector populations access and ultimately destroy the graft renal tubules (rejection per se) have received remarkably little attention. This is an important gap in our knowledge of transplantation immunology, because epithelial compartments comprise the functional elements of most commonly transplanted organs including not only kidney, but also liver, lung, pancreas, and intestine. Furthermore, there is increasing evidence that attack of graft epithelial elements by CD8-effector populations not only causes short-term graft dysfunction but is also a major contributor to development of chronic allograft nephropathy and late graft loss, which now represent the salient clinical problems. Recent studies of the T-cell integrin, alpha(E)beta(7) (CD103), have provided insight into the mechanisms that promote interaction of CD8 effectors with graft epithelial compartments. The purpose of this communication is to review the known properties of the CD103 molecule and its postulated role in the efferent phase of renal allograft rejection.  相似文献   
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