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991.
Aims
Altered expression of epithelial or stromal caveolin-1 (Cav-1) is observed in various types of human cancers. However, the clinical significance of Cav-1 expression in gastric cancer (GC) remains largely unknown. The present study aims to explore the clinicopathological significance and prognostic value of both tumor cells and cancer associated fibroblasts (CAFs) Cav-1 in GC.Methods and Results
Quantum dots immunofluorescence histochemistry was performed to examine the expression of Cav-1 in 20 cases of gastritis without intestinal metaplasia (IM), 20 cases of gastritis with IM and 286 cases of GC. Positive rates of epithelial Cav-1 in gastritis without IM, gastritis with IM and GC showed a decreasing trend (P = 0.012). Low expression of Cav-1 in CAFs but not in tumor cells was an independent predictor of poor prognosis in GC patients (P = 0.034 and 0.005 respectively in disease free survival and overall survival). Cav-1 level in tumor cells and CAFs showed no significant correlation with classic clinicopathological features.Conclusions
Loss of epithelial Cav-1 may promote malignant progression and low CAFs Cav-1 level herald worse outcome of GC patient, suggesting CAFs Cav-1 may be a candidate therapeutic target and a useful prognostic marker of GC. 相似文献992.
Strontium (Sr) can promote the process of bone formation. To improve bioactivity, porous allograft bone scaffolds (ABS) were doped with Sr and the mechanical strength and bioactivity of the scaffolds were evaluated. Sr-doped ABS were prepared using the ion exchange method. The density and distribution of Sr in bone scaffolds were investigated by inductively coupled plasma optical emission spectrometry (ICP-OES), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray spectroscopy (EDS). Controlled release of strontium ions was measured and mechanical strength was evaluated by a compressive strength test. The bioactivity of Sr-doped ABS was investigated by a simulated body fluid (SBF) assay, cytotoxicity testing, and an in vivo implantation experiment. The Sr molar concentration [Sr/(Sr+Ca)] in ABS surpassed 5% and Sr was distributed nearly evenly. XPS analyses suggest that Sr combined with oxygen and carbonate radicals. Released Sr ions were detected in the immersion solution at higher concentration than calcium ions until day 30. The compressive strength of the Sr-doped ABS did not change significantly. The bioactivity of Sr-doped material, as measured by the in vitro SBF immersion method, was superior to that of the Sr-free freeze-dried bone and the Sr-doped material did not show cytotoxicity compared with Sr-free culture medium. The rate of bone mineral deposition for Sr-doped ABS was faster than that of the control at 4 weeks (3.28±0.23 µm/day vs. 2.60±0.20 µm/day; p<0.05). Sr can be evenly doped into porous ABS at relevant concentrations to create highly active bone substitutes. 相似文献
993.
Background
To isolate plant-derived compounds with antimicrobial activity from the leaves of Mikania micrantha, to determine the compounds configuration, and to evaluate their antimicrobial activity against eight plant pathogenic fungi (Exserohilum turcicum, Colletotrichum lagenarium, Pseudoperonispora cubensis, Botrytis cirerea, Rhizoctonia solani, Phytophthora parasitica, Fusarium solani, and Pythium aphanidermatum,) and four plant pathogenic bacteria (gram negative bacteria: Ralstonia dolaanacearum, Xanthomonas oryzae pv. Oryzae, Xanthomonas Campestris pv. Vesicatoria, and Xanthomonas campestris pv. Citri), and four bacteria (gram positive bacteria: Staphyloccocus aureus, Bacillus subtilis, Micrococcus luteus, and Bacillus cereus).Methods and Results
Antimicrobial constituents of the leaves of M. micrantha were isolated using bioactivity- guided fractionation. The antifungal activity of the isolated compounds was evaluated by the inhibit hypha growth method and inhibit spore germination method. Characterization of antibacterial activity was carried out using the minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs). MIC and MBC were determined by the broth microdilution method. Six compounds – deoxymikanolide, scandenolide, dihydroscandenolide, mikanolide, dihydromikanolide, and m - methoxy benzoic acid – have been isolated from leaves of Mikania micrantha H. B. K. Deoxymikanolide, scandenolide, and dihydroscandenolide were new compounds. The result of bioassay showed that all of isolated compounds were effective against tested strains and deoxymikanolide showed the strongest activity.Conclusions and Significance
The leaves of M. micrantha may be a promising source in the search for new antimicrobial drugs due to its efficacy and the broadest range. Meanwhile, adverse impact of M. micrantha will be eliminated. 相似文献994.
Kentaro Inoue Jun Wada Jun Eguchi Atsuko Nakatsuka Sanae Teshigawara Kazutoshi Murakami Daisuke Ogawa Takahiro Terami Akihiro Katayama Atsuhito Tone Izumi Iseda Kazuyuki Hida Masao Yamada Tomohisa Ogawa Hirofumi Makino 《PloS one》2013,8(10)
We analyzed the urine samples of patients with type 2 diabetes at various stages of diabetic nephropathy by lectin microarray to identify a biomarker to predict the progression of diabetic nephropathy. Japanese patients with type 2 diabetes at various stages of nephropathy were enrolled and we performed lectin microarray analyses (n = 17) and measured urinary excretion of fetuin-A (n = 85). The increased signals of urine samples were observed in Siaα2-6Gal/GalNAc-binding lectins (SNA, SSA, TJA-I) during the progression of diabetic nephropathy. We next isolated sialylated glycoproteins by using SSA-lectin affinity chromatography and identified fetuin-A by liquid chromatography–tandem mass spectrometer. Urinary excretion of fetuin-A significantly increased during the progression of albuminuria (A1, 0.40±0.43; A2, 0.60±0.53; A3 1.57±1.13 ng/gCr; p = 7.29×10−8) and of GFR stages (G1, 0.39±0.39; G2, 0.49±0.45; G3, 1.25±1.18; G4, 1.34±0.80 ng/gCr; p = 3.89×10−4). Multivariate logistic regression analysis was employed to assess fetuin-A as a risk for diabetic nephropathy with microalbuminuria or GFR<60 mL/min. Fetuin-A is demonstrated as a risk factor for both microalbuminuria and reduction of GFR in diabetic nephropathy with the odds ratio of 4.721 (1.881–11.844) and 3.739 (1.785–7.841), respectively. Collectively, the glycan profiling analysis is useful method to identify the urine biomarkers and fetuin-A is a candidate to predict the progression of diabetic nephropathy. 相似文献
995.
Myoung Jae Kang Kyoung Min Kim Jun Sang Bae Ho Sung Park Ho Lee Myoung Ja Chung Woo Sung Moon Dong Geun Lee Kyu Yun Jang 《Translational oncology》2013,6(3):282-289
BACKGROUND: Clear cell renal cell carcinoma (CRCC) is the most common malignant tumor of the kidney, and the clinical outcome of CRCC is related with the metastatic potential of CRCC. A significant proportion of metastatic CRCC remains incurable. Recently, immunotherapy against specific targets such as programmed death 1 (PD1) has been adapted for fatal cases of CRCC. MATERIALS AND METHODS: In this study, we aimed to evaluate the potential of tumor-infiltrating PD1-positive lymphocytes or FoxP3-positive regulatory T cells (Tregs) as predictors of the metastatic potential or prognosis of CRCC and investigate possible correlations with Epstein-Barr virus (EBV) infection in 199 cases of CRCC. RESULTS: PD1 positivity, high Treg number, and EBV infection all predicted poor overall survival (OS) by univariate analysis. PD1 positivity and high Treg numbers were also significantly correlated with more distant metastatic relapse (DMR) and poor relapse-free survival (RFS) by univariate analysis. PD1 positivity and high Treg number were independent prognostic indicators for OS. In addition, PD1 positivity was an independent predictor of RFS and DMR. EBV infection was an independent predictor of OS of CRCC. CONCLUSION: This study demonstrates that intratumoral infiltration of PD1-positive or FoxP3-positive lymphocytes can be used as significant prognostic indicators of CRCC and PD1 positivity could be very helpful in the prediction of latent distant metastasis of CRCCs. Therefore, evaluation of the infiltration of PD-positive cells or Tregs in CRCC may be useful diagnostic tools for the selection of patients who could benefit from PD1- or Treg-based immunotherapy. 相似文献
996.
Ho Sung Park Jun Sang Bae Sang Jae Noh Kyung Min Kim Ho Lee Woo Sung Moon Myoung Ja Chung Myoung Jae Kang Dong Geun Lee Kyu Yun Jang 《Translational oncology》2013,6(3):370-381
BACKGROUND: Recently, deleted in breast cancer 1 (DBC1) has been suggested as a poor prognostic indicator of various human cancers and may possibly have a role as a coactivator of androgen receptor (AR). However, their roles in lymphoma are still unknown. MATERIALS AND METHODS: We investigated the effect of the expression of DBC1 and AR in diffuse large B cell lymphoma (DLBCL). Immunohistochemical expression of DBC1 and AR were evaluated in 101 DLBCL samples by tissue microarray. RESULTS: Positive expression of DBC1 and AR was seen in 73% and 70% of DLBCL, respectively. In total DLBCL patients, DBC1 and AR expression were significantly associated with high clinical stage, elevated serum lactate dehydrogenase levels, and high international prognostic index scores, and they predicted shorter overall survival (OS) and relapse-free survival (RFS) by univariate analysis. DBC1 expression was also an independent prognostic indicator by multivariate analysis (OS, P = .017; RFS, P = .004). Especially, both DBC1 and AR expression significantly correlated with shorter OS and RFS in non-germinal center B cell (non-GCB)-type DLBCL by univariate analysis. In multivariate analysis, DBC1 expression was an independent prognostic predictor for OS (P = .035) and AR expression significantly correlated with RFS (P = .005). CONCLUSION: We demonstrate that the expression of DBC1 and AR are significant prognostic indicators for DLBCL patients, especially for unfavorable non-GCB-type DLBCL. 相似文献
997.
Eunjung Lee Ki-Woong Jeong Areum Shin Bonghwan Jin Hum Nath Jnawali Bong-Hyun Jun Jee-Young Lee Yong-Seok Heo Yangmee Kim 《BMB reports》2013,46(12):594-599
The anti-inflammatory activity of eriodictyol and its mode of action were investigated. Eriodictyol suppressed tumor necrosis factor (mTNF)-α, inducible nitric oxide synthase (miNOS), interleukin (mIL)-6, macrophage inflammatory protein (mMIP)-1, and mMIP-2 cytokine release in LPS-stimulated macrophages. We found that the anti-inflammatory cascade of eriodictyol is mediated through the Toll-like Receptor (TLR)4/CD14, p38 mitogen-activated protein kinases (MAPK), extracellular-signalregulated kinase (ERK), Jun-N terminal kinase (JNK), and cyclooxygenase (COX)-2 pathway. Fluorescence quenching and saturation-transfer difference (STD) NMR experiments showed that eriodictyol exhibits good binding affinity to JNK, 8.79 × 105 M-1. Based on a docking study, we propose a model of eriodictyol and JNK binding, in which eriodictyol forms 3 hydrogen bonds with the side chains of Lys55, Met111, and Asp169 in JNK, and in which the hydroxyl groups of the B ring play key roles in binding interactions with JNK. Therefore, eriodictyol may be a potent anti-inflammatory inhibitor of JNK. [BMB Reports 2013; 46(12): 594-599] 相似文献
998.
采用析因设计法(Plackett-burman)对影响Chlorella zofingiensis高产虾青素的相关因素进行评价,发现硝酸钠、光照强度、二价铁离子及醋酸钠浓度对虾青素产量影响显著.利用中心组合设计(central composite design)及响应面分析对影响虾青素产量的关键因素做进一步的优化,得到较佳的试验点为二价铁离子浓度0.41 mmol/L,硝酸钠浓度0.8 mmol/L,醋酸钠浓度37.1 mmol/L,光照强度650 E/m2×s.优化后虾青素产量从7.890mg/L提高到19.81mg/L,比优化前提高了2.5倍. 相似文献
999.
功能性包涵体的研究进展 总被引:1,自引:0,他引:1
利用原核系统表达外源重组蛋白的一个特点是表达蛋白多以包涵体形式存在。在过去人们一直认为包涵体是错误折叠、无生物活性的蛋白,需要经过变复性的过程重新获得有生物活性、可溶的蛋白,因而变复性条件的摸索迄今仍然是该领域的难点。但近几年的研究表明包涵体并非都是无生物活性的,功能性包涵体(或者称为非传统意义包涵体) 概念的提出是该领域的一个重大研究进展。由于功能性包涵体本身具有生物活性,可在非变性条件下提取,目前已经在生命科学的基础研究、生物制药、生物材料、生物催化等领域展现出良好的应用前景。重点从功能性包涵体的定义、形成机理、提取条件等近期研究进展进行综述,以期为原核细胞表达和工业生产重组蛋白药物提供新的思路。 相似文献
1000.