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Recently, accumulating evidence has implicated the dysregulation of autophagy as underlying the pathophysiology of several neurodegenerative diseases. The human neuronal cell line SH-SY5Y was exposed to 1-Methyl-4-phenylpyridinium (MPP+). The mechanism is that the sustained activation of the MAPK/ERK pathway by MPP+ alters autophagy selectively at the maturation step, significant increasing in autophagy formation and delaying in autophagy degradation in SHSY5Y cells. In this study, we provided evidences that estrogen was capable of promoting SHSY5Y cells survival in MPP+-treated group. In particular, the up-regulation of mERα, but not mERβ, was associated with a rapid and transient activation of ERK phosphorylation compatible with promoting autophagy maturation. The up-regulation of mERα changed the sustained activation of ERK phosphorylation in MPP+-treated group into a temporary activation. Taken together, these findings strongly support that the expression of mERα promotes the maturation of autophagosomes into functional autolysosomes by regulating ERK, determining SHSY5Y cells survival.  相似文献   
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Renal cell carcinoma has become the most common subtype of kidney cancer, and has the highest propensity to manifest as metastatic disease. Because of lack of knowledge in events that correlated with tumor cell migration and invasion, few therapeutic options are available. Therefore, in current study, we explore the anti-tumoral effect of a potential chemopreventive natural product, quercetin, combined with anti-sense oligo gene therapy (inhibiting Snail gene). We found that either one of them had the remarkable effects in suppressing cell proliferation and migration, inducing cell cycle arrest and apoptosis in a ccRCC cell line, Caki-2 cells. The combination of both means provides even strong suppressive effects toward these ccRCC cells. Our study, for the first time, provides the possibility of using a novel treatment for renal cancer, by combining natural product and gene therapy.  相似文献   
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Metastases to the breast from extramammary malignancies are extremely rare. Ruling out the diagnosis of primary breast tumor is important in order to decide on clinical management and predict prognosis. We report a case of metastasis to the breast from a pulmonary adenocarcinoma, with extensive micropapillary component, diagnosed concomitantly with the primary tumor. A 52 year-old female patient presented with mammary gland tingling and dyspnea accompanied with fatigued of 4 months duration and a nodular shadows in the front of the upper lobe was found on a chest computed tomography (CT) scan. The original clinical diagnosis was right breast cancer with lung and bone metastasis, or breast and lung double primary cancers. In addition,on physical examination a poorly defined mass was noted in the upper outer quadrant of the right breast. The patient underwent thoracocentesis and breast biopsy. By imageology, cytology, histology and immunohistochemistry, we diagnosed primary lung cancer with metastases to the right breast and bone. The metastatic anatomic sites demonstrated histologically extensive micropapillary component, which is recently recognized as an important prognostic factor. The patient was administered 4 cycles of cisplatin and docetaxel, although no clinical response was seen, the patient is still alive 9 months after diagnosis. The result of immunohistochemistry is a useful supplement in differential diagnosis.  相似文献   
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The objective of the present study was to systematically investigate the influence of molecular weight (MW) and concentration of carboxymethyl chitosan (CMC), which served as non-collagenous protein (NCP) surrogates, on biomimetic mineralization of type I collagen. Supersaturated CMC-stabilized amorphous calcium-phosphate (CMC-ACP) dispersions containing different MWs (20 kDa, 60 kDa, 150 kDa) and concentrations (25, 50, 100, 200, 400 μg ml−1) of CMC were prepared. After mineralization in the aforementioned dispersions for 7 days, the pattern and extent of biomimetic mineralization of collagen scaffolds were investigated. Our study showed that increasing CMC concentration resulted in increasing stability and decreasing particle size of CMC-ACP dispersions. Images from scanning and transmission electron microscopy revealed that intrafibrillar mineralization of collagen was obtained with 20k-200, 60k-100, 60k-200 and 150k-200 CMC-ACP dispersions, with hydroxyapatite (HAp) formation confirmed by Fourier transform infrared spectroscopy and X-ray diffraction measurements, whereas HAp formed extrafibrillar clusters in other collagen scaffolds. Thermogravimetric analysis showed that the combined effect of MW and concentration of CMC contributed to different extents of biomimetic mineralization, and was correlated with the stability and particle size of CMC-ACP dispersions, and the size-exclusion characteristics of type I collagen. The results of this work support the effective function of CMC as NCP analogs, and provide parameters of MWs and concentrations of CMC for applications in hard tissue engineering as well as insights into intersections of mechanisms in biomimetic mineralization.

The study systematically investigated the influence of molecular weight and concentration of CMC on CMC-ACP nanoparticles and biomimetic mineralization.  相似文献   
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Peptide-containing hydrogels have become a research hotspot due to their unique secondary structure and biocompatibility. Herein, we used amino-terminated F127 as a macroinitiator to initiate the ring-opening polymerization of l-lysine(z)-NCA, and the obtained oligo(lysine)-modified F127 (FL) had degrees of polymerization of lysine of 2, 5, and 8. The results showed that the FL hydrogels had reversible temperature-dependent sol–gel transitions, and the introduction of lysine increased the critical gel temperature. In the dilute solution of FL, the micelle size increased and aggregated as the pH increased; the micelle grew into a rod-like shape under alkaline conditions. Scanning electron micrographs showed that the interior of the FL hydrogel had a more complete porous structure. The FL-2 hydrogel loaded with 5-fluorouracil exhibited an approximately linear release trend within 12 h and has good biocompatibility. Therefore, FL hydrogels have potential applications in the field of biomedicine.

Oligo(lysine)-F127 hydrogels have a temperature-responsive sol–gel transition and pH-responsive micelle morphology.  相似文献   
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