Selective over-expression of endothelin-1 in endothelial cells exacerbates inner retinal edema and neuronal death in ischemic retina

The level of endothelin-1 (ET-1), a potent vasoconstrictor, was associated with retinopathy under ischemia. The effects of endothelial endothelin-1 (ET-1) over-expression in a transgenic mouse model using Tie-1 promoter (TET-1 mice) on pathophysiological changes of retinal ischemia were investigated by intraluminal insertion of a microfilament up to middle cerebral artery (MCA) to transiently block the ophthalmic artery. Two-hour occlusion and twenty-two-hour reperfusion were performed in homozygous (Hm) TET-1 mice and their non-transgenic (NTg) littermates. Presence of pyknotic nuclei in ganglion cell layer (GCL) was investigated in paraffin sections of ipsilateral (ischemic) and contralateral (non-ischemic) retinae, followed by measurement of the thickness of inner retinal layer. Moreover, immunocytochemistry of glial fibrillary acidic protein (GFAP), glutamine synthetase (GS) and aquaporin-4 (AQP4) peptides on retinal sections were performed to study glial cell reactivity, glutamate metabolism and water accumulation, respectively after retinal ischemia. Similar morphology was observed in the contralateral retinae of NTg and Hm TET-1 mice, whereas ipsilateral retina of NTg mice showed slight structural and cellular changes compared with the corresponding contralateral retina. Ipsilateral retinae of Hm TET-1 mice showed more significant changes when compared with ipsilateral retina of NTg mice, including more prominent cell death in GCL characterized by the presence of pyknotic nuclei, elevated GS immunoreactivity in Müller cell bodies and processes, increased AQP-4 immunoreactivity in Müller cell processes, and increased inner retinal thickness. Thus, over-expression of endothelial ET-1 in TET-1 mice may contribute to increased glutamate-induced neurotoxicity on neuronal cells and water accumulation in inner retina leading to edema. © 2011 Cheung et al.published_or_final_versio

Changes in Staff Expectations, Competence, and Confidence in Providing EOL Care after Launching a 2-year End-of-life Care Pilot Project in Care and Attention Home

Conference Theme: Clinical, Legal and Administrative ChallengesFree Paper Presentation Ipublished_or_final_versio

Oestrogenic activity of mimosine on MCF-7 breast cancer cell line through the ERα-mediated pathway

Hormone replacement therapy has been a conventional treatment for postmenopausal symptoms in women. However, it has potential risks of breast and endometrial cancers. The aim of this study was to evaluate the oestrogenicity of a plant-based compound, mimosine, in MCF-7 cells by in silico model. Cell viability and proliferation, ERα-SRC1 coactivator activity and expression of specific ERα-dependent marker TFF1 and PGR genes were evaluated. Binding modes of 17β-oestradiol and mimosine at the ERα ligand binding domain were compared using docking and molecular dynamics simulation experiments followed by binding interaction free energy calculation with molecular mechanics/Poisson-Boltzmann surface area. Mimosine showed increased cellular viability (64,450 cells/ml) at 0.1 μM with significant cell proliferation (120.5%) compared to 17β-oestradiol (135.2%). ER antagonist tamoxifen significantly reduced proliferative activity mediated by mimosine (49.9%). Mimosine at 1 μM showed the highest ERα binding activity through increased SRC1 recruitment at 186.9%. It expressed TFF1 (11.1-fold at 0.1 μM) and PGR (13.9-fold at 0.01 μM) genes. ERα-mimosine binding energy was -49.9 kJ/mol, and it interacted with Thr347, Gly521 and His524 of ERα-LBD. The results suggested that mimosine has oestrogenic activity

在香港護理安老院舍推行生命晚期照護服務–成本效益分析

Conference Theme: Ageing at Home-Mobilizing Community Participation for Long Term Care of Elderlypostprin

Preclinical analysis of the anti-tumor and anti-metastatic effects of Raf265 on colon cancer cells and CD26(+) cancer stem cells in colorectal carcinoma

© 2015 Chow et al.Background: In colorectal carcinoma (CRC), activation of the Raf/MEK/ERK signaling pathway is commonly observed. In addition, the commonly used 5FU-based chemotherapy in patients with metastatic CRC was found to enrich a subpopulation of CD26+ cancer stem cells (CSCs). As activation of the Raf/MEK/ERK signaling pathway was also found in the CD26+ CSCs and therefore, we hypothesized that an ATP-competitive pan-Raf inhibitor, Raf265, is effective in eliminating the cancer cells and the CD26+ CSCs in CRC patients. Methods: HT29 and HCT116 cells were treated with various concentrations of Raf265 to study the anti-proliferative and apoptotic effects of Raf265. Anti-tumor effect was also demonstrated using a xenograft model. Cells were also treated with Raf265 in combination with 5FU to demonstrate the anti-migratory and invasive effects by targeting on the CD26+ CSCs and the anti-metastatic effect of the combined treatment was shown in an orthotopic CRC model. Results: Raf265 was found to be highly effective in inhibiting cell proliferation and tumor growth through the inhibition of the RAF/MEK/ERK signaling pathway. In addition, anti-migratory and invasive effect was found with Raf265 treatment in combination with 5FU by targeting on the CD26+ cells. Finally, the anti-tumor and anti-metastatic effect of Raf265 in combination with 5FU was also demonstrated. Conclusions: This preclinical study demonstrates the anti-tumor and anti-metastatic activity of Raf265 in CRC, providing the basis for exploiting its potential use and combination therapy with 5FU in the clinical treatment of CRC.published_or_final_versio

Prognostic significance of CD26 in patients with colorectal cancer

Background: CD26, dipeptidyl peptidase IV, was discovered firstly as a membrane-associated peptidase on the surface of leukocyte. We previously demonstrated that a subpopulation of CD26+ cells were associated with the development of distant metastasis, enhanced invasiveness and chemoresistance in colorectal cancer (CRC). In order to understand the clinical impact of CD26, the expression was investigated in CRC patient's specimens. This study investigated the prognostic significance of tumour CD26 expression in patients with CRC. Examination of CD26+ cells has significant clinical impact for the prediction of distant metastasis development in colorectal cancer, and could be used as a selection criterion for further therapy. Methods: Tumour CD26 expression levels were studied by immunohistochemistry using Formalin-fixed paraffin embedded (FFPE) tissues in 143 patients with CRC. Tumour CD26 expression levels were correlated with clinicopathological features of the CRC patients. The prognostic significance of tumour tissue CD26 expression levels was assessed by univariate and multivariate analyses. Result: CD26 expression levels in CRC patients with distant metastasis were significantly higher than those in non-metastatic. High expression levels of CD26 were significantly associated with advanced tumour staging. Patients with a high CD26 expression level had significantly worse overall survival than those with a lower level (p<0.001). Conclusions: The expression of CD26 was positively associated with clinicopathological correlation such as TNM staging, degree of differentiation and development of metastasis. A high CD26 expression level is a predictor of poor outcome after resection of CRC. CD26 may be a useful prognostic marker in patients with CRC. © 2014 Lam et al.published_or_final_versio

Acupuncture improves cognitive function: A systematic review

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