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951.
Cyclin D1 gene (CCND1) numerical aberrations are independent prognostic indicators of head and neck squamous cell carcinomas (HNSCCs). High epidermal growth factor receptor gene (EGFR) copy number is associated with poor prognosis in lung cancer, but such findings are controversial in oral SCCs (OSCCs). We analyzed copy number status in CCND1 and EGFR in OSCC patients and its association with clinical outcome.EGFR and CCND1 statuses were analyzed in 85 OSCC patients by fluorescence in situ hybridization (FISH) of specimens obtained by fine-needle aspiration biopsy.CCND1 numerical aberration was found in 35 of 85 tumors (41%), and aberrant EGFR copy number was observed in 36 (42%). Gene amplification (GA) was dominant among CCND1 copy number changes (14/35:40%). Balanced trisomy (BT) was the most frequently observed EGFR aberration (17/36:47%). In a multivariate Cox's proportional hazards analysis, CCND1 GA was correlated with disease-free survival (P < 0.001), whereas EGFR BT was significantly correlated with overall survival (P = 0.001). Patients with a combination of CCND1 GA and/or EGFR BT had significantly poorer clinical outcome.CCND1 and EGFR copy number changes were frequent in OSCC and had differing aberration patterns. CCND1 GA and EGFR BT statuses by dual-color FISH were the predominant predictors of clinical outcome. Further investigation is needed to determine the implications for EGFR inhibitor therapy in OSCC.  相似文献   
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Backgrounds

Despite current therapies, acute heart failure (AHF) remains a major public health burden with high rates of in-hospital and post-discharge morbidity and mortality. Carperitide is a recombinantly produced intravenous formulation of human atrial natriuretic peptide that promotes vasodilation with increased salt and water excretion, which leads to reduction of cardiac filling pressures. A previous open-label randomized controlled study showed that carperitide improved long-term cardiovascular mortality and heart failure (HF) hospitalization for patients with AHF, when adding to standard therapy. However, the study was underpowered to detect a difference in mortality because of the small sample size.

Methods

Low-dose Administration of Carperitide for Acute Heart Failure (LASCAR-AHF) is a multicenter, randomized, open-label, controlled study designed to evaluate the efficacy of intravenous carperitide in hospitalized patients with AHF. Patients hospitalized for AHF will be randomly assigned to receive either intravenous carperitide (0.02 μg/kg/min) in addition to standard treatment or matching standard treatment for 72 h. The primary end point is death or rehospitalization for HF within 2 years. A total of 260 patients will be enrolled between 2013 and 2018.

Conclusion

The design of LASCAR-AHF will provide data of whether carperitide reduces the risk of mortality and rehospitalization for HF in selected patients with AHF.
  相似文献   
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PURPOSE: The corneal epithelium provides a barrier that is both important for corneal homeostasis and dependent on tight junctions (TJs) between adjacent epithelial cells. The authors examined the effects of tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, on barrier function and the expression of TJ proteins in simian virus 40-transformed human corneal epithelial (HCE) cells. METHODS: The barrier function of cultured HCE cells was evaluated by measurement of transepithelial electrical resistance (TER). The subcellular distribution of the TJ proteins zonula occludens-1 (ZO-1) and occludin and that of the p65 subunit of nuclear factor-kappaB (NF-kappaB) were determined by immunofluorescence staining. The expression of ZO-1 and occludin and the phosphorylation and degradation of the NF-kappaB inhibitory protein IkappaB-alpha were examined by immunoblot analysis. RESULTS: TNF-alpha induced a decrease in the TER of HCE cells in a concentration- and time-dependent manner. It also induced the disappearance of ZO-1 from the interfaces of neighboring HCE cells without affecting the localization of occludin. The abundance of neither ZO-1 nor occludin was affected by TNF-alpha. TNF-alpha induced the phosphorylation and downregulation of IkappaB-alpha and the translocation of the p65 subunit of NF-kappaB to the nucleus. The NF-kappaB inhibitor curcumin blocked the effects of TNF-alpha on TER and the subcellular localization of ZO-1 at late phase. CONCLUSIONS: TNF-alpha disrupted the barrier function of HCE cells, apparently by affecting the localization of ZO-1 at TJs in a manner dependent on NF-kappaB at late phase. This action of TNF-alpha may contribute to the loss of corneal epithelial barrier function associated with ocular inflammation.  相似文献   
958.
The cornea: stasis and dynamics   总被引:1,自引:0,他引:1  
Nishida T 《Nippon Ganka Gakkai zasshi》2008,112(3):179-212; discussion 213
The physiological roles of the cornea are to conduct external light into the eye, focus it, together with the lens, onto the retina, and to provide rigidity to the entire eyeball. Good vision thus requires maintenance of the transparency and proper refractive shape of the cornea. Although the cornea appears to be a relatively static structure, dynamic processes operate within and around the cornea at the tissue, cell, and molecular level. In this article, I review the mechanisms responsible for maintenance of corneal homeostasis as well as the development of new modes of treatment for various corneal diseases. I. The static cornea: structure and physiological functions. The cornea is derived from ectoderm, so that it can be considered as transparent skin. It is devoid of blood vessels and manifests the highest sensitivity in the entire body. The surface of the cornea is covered by tear fluid, which serves both as a lubricant and as a conduit for regulatory molecules. The cornea is also supplied with oxygen and various nutrients by the aqueous humor and a loop vascular system in addition to tear fluid. The cornea interacts with its surrounding tissues directly as well as indirectly through tear fluid or aqueous humor, with such interactions playing an important role in the regulation of corneal structure and functions. The resident cells of the cornea-epithelial cells, fibroblasts (keratocytes), and endothelial cells--also engage in mutual interactions through network systems. These interactions as well as those with infiltrated cells and regulation by nerves contribute to the maintenance of the normal structure and functions of the cornea as well as to the repair of corneal injuries. II. The dynamic cornea: maintenance of structure and functions by network systems. Developments in laser and computer technology have allowed observation of the cells and collagen fibers within the cornea. Furthermore, progress in cell and molecular biology has allowed characterization of dynamic network systems-including cell-cell and cell-extracellular matrix interactions as well as cytokines and neural factors-that contribute to the maintenance of corneal transparency and shape. III. Disruption of network systems: persistent corneal epithelial defects and corneal ulcer. Selection of the appropriate treatment for pathologic lesions of the cornea and the accompanying decrease in visual acuity requires localization of the lesion with regard to the epithelium, stroma, or endothelium of the cornea. In certain instances, however, it is not possible to determine the cause of the problem within the cornea. In such cases, the cause of the pathologic lesion and the target for treatment may lie in the surrounding tissues or environment. For example, corneal epithelial wound healing may be delayed, leading to the development of persistent epithelial defects, as a result of disruption of intercellular junctions between epithelial cells, an abnormality of the corneal basement membrane, altered concentrations of various cytokines in tear fluid, a lowered corneal sensation, or allergic reactions in the lid conjunctiva. Loss of corneal epithelial barrier function can further allow inflammatory cytokines present in tear fluid, together with infiltrated cells, to activate keratocytes and elicit excessive degradation of collagen in the stroma, thereby giving rise to corneal ulcer. IV. Development of new drugs for corneal diseases. We have attempted to apply the results of basic scientific research to the development of new drugs for corneal diseases that remain difficult to treat. The process of authorization for new drugs from the Ministry of Health, Labor, and Welfare takes more than two decades, however. The path from the bench to clinical practice is thus a long one. 1. Development of eyedrops for treatment of persistent corneal epithelial defects. We demonstrated the clinical efficacy of fibronectin eyedrops for the treatment of persistent epithelial defects of the cornea. However, the possibility of blood-borne infections has interfered with the development of serum-derived fibronectin as a drug. An automated machine for the preparation of autologous fibronectin eyedrops has therefore recently been developed. Furthermore, in seeking an alternative to fibronectin eyedrops, we are investigating the effects of a peptide corresponding to the second cell-binding domain of fibronectin on corneal epithelial wound healing. Considering that urokinase-type plasminogen activator may be expressed at the site of corneal epithelial defects and facilitates epithelial migration, the potential clinical application of annexin V, which stimulates the secretion of urokinase-type plasminogen activator for the treatment of persistent corneal epithelial defects is also now under investigation in Japan. 2. Development of eyedrops for treatment of neurotrophic keratopathy. Substance P, a neurotransmitter, stimulates corneal epithelial migration in a synergistic manner with insulin-like growth factor (IGF)--1. We have shown that eyedrops containing both the substance P-derived peptide FGLM-amide and the IGF-1--derived peptide SSSR are effective for the treatment of persistent corneal epithelial defects in individuals with diabetic keratopathy or neurotrophic keratopathy, both of which are associated with a reduction in corneal sensation. 3. Development of drugs for corneal ulcer. Treatment of corneal infection with antibiotics does not necessarily halt the process of corneal ulceration, which is characterized by excessive degradation of stromal collagen, or resolve persistent corneal epithelial defects. In addition to eyedrops for the treatment of persistent corneal epithelial defects, we have therefore also been working on the development of new drugs for the treatment of corneal ulcer. To this end, we have established an experimental system in which corneal fibroblasts are cultured in a three-dimensional collagen gel. With this system, we have shown that triptolide and steroids inhibit collagen degradation by corneal fibroblasts. Triptolide or its derivatives are thus potential drugs for the treatment of corneal ulcer and would work by acting directly on corneal fibroblasts rather than by inhibiting the secreted enzymes(matrix metalloproteinases) responsible for collagen degradation.  相似文献   
959.
BACKGROUND: The anti-tumor necrosis factor (TNF)-alpha agent has been shown to be effective for the treatment of various inflammatory diseases, including rheumatoid arthritis and inflammatory disorders of the colon. It also appears to be effective for treatment of macular edema secondary to uveitis. CASE: A 57-year-old woman complained of blurred vision in both eyes. Inflammatory cells in the anterior chamber, vitreous opacity, and cystoid macular edema (CME) were detected in both eyes. Her corrected visual acuity was 0.1 OD and 0.3 OS. Macular thickness measured by optical coherence tomography was 784 and 714 microm for the right and left eyes, respectively. She had active rheumatoid arthritis, and treatment with etanercept was started. The extent of CME decreased gradually after the treatment was begun, with the macular thickness having decreased to 204 and 190 microm in the right and left eyes, respectively, and visual acuity having improved to 0.9 OD and 1.2 OS by 4 months after the beginning of treatment. CONCLUSION: These results suggest that etanercept may be effective for the treatment of CME secondary to uveitis, and they implicate TNF-a in the pathogenesis of uveitic CME.  相似文献   
960.
Wakuta M  Chikama T  Takahashi N  Nishida T 《Cornea》2008,27(1):107-110
PURPOSE: To describe a case of bilateral corneal epithelial dysplasia in which each lesion was characterized by both laser confocal biomicroscopy and cytokeratin immunofluorescence. METHODS: A 52-year-old Japanese woman with bilateral corneal epithelial dysplasia was treated by corneal epithelial debridement. We observed the affected area with laser confocal biomicroscopy before and after treatment and examined the immunofluorescence of cytokeratins to examine the characteristics of the abnormal epithelial cells. RESULTS: Laser confocal biomicroscopy revealed the atypical epithelial cells in all layers of the corneal epithelium as well as the reconstituted normal structure of the corneal epithelium after epithelial debridement. Immunofluorescence of cytokeratin 12 (K12) and K4 revealed the presence of four types of cells (those positive for one, both or neither of these cytokeratins) in each lesion. CONCLUSION: Cells expressing both K12 and K4 probably represented dysplastic cells that had invaded the cornea via the limbus and adopted characteristics of corneal epithelial cells. Cells lacking both K12 and K4 were probably either undifferentiated cells or epithelial cells in which cytokeratin expression had not been initiated.  相似文献   
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