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221.
Summary A murine anti-(human gastric carcinoma) monoclonal antibody, GL-013 (IgG1), which reacts with a high-molecular-mass glycoprotein from colorectal tumour tissue [Yang and Price (1989) Anticancer Res 9: 1707], was examined for reactivity against a panel of purified and partially purified antigens associated with tumours of the gastrointestinal tract. These included carcinoembryonic antigen (CEA), normal cross-reacting antigen, Y-hapten glycoproteins, and perchloric acid extracts and glycolipid preparations from colorectal tumours. While the GL-013 antibody failed to bind to these antigens, it was found to react strongly with synthetic peptides with sequences based upon that reported for the protein core of a human gastrointestinal mucin [Barnd et al. (1989) Proc Natl Acad Sci USA 86: 7159; Gum et al. (1989) J Biol Chem 264: 6480]. In control tests, a series of other anti-(colorectal tumour) antibodies (IgG1 and IgG3), with broad reactivity towards gastrointestinal carcinomas, as well as an anti-CEA antibody, (IgG1) failed to react with the synthetic peptides. It is concluded that the anti-(gastric carcinoma) monoclonal antibody GL-013 binds to a threonine-rich peptide epitope expressed within the protein core of gastrointestinal mucins. Present address: Cancer Research Institute, China Medical University, Shenyang, Liaoning, People's Republic of China  相似文献   
222.
Onychomycosis caused by Scopulariopsis brumptii   总被引:1,自引:0,他引:1  
Scopulariopsis brumptii was isolated from nail lesions in left hand of a 42 year-old-farmer. The direct microscopic examination of the nail samples revealed light brown, septate, branched fungal hyphae along with thick-walled spherical cells. The histopathological examination showed involvement of internal phase of the nail plate. Amongst the antimycotics tested against S. brumptii In vitro oxiconazole was found to be the most active with MIC value of 10 g/ml–1. This report documents the first instance of onychomycosis caused by S. brumptii.  相似文献   
223.
微囊藻属多肽类酶抑制剂研究进展   总被引:5,自引:0,他引:5  
本文综述了微囊藻属蓝藻多肽类酶抑制剂的产生、结构特征、药理活性以及应用前景。  相似文献   
224.
The solid‐phase synthesis, structural characterization, and biological evaluation of a small library of cancer‐targeting peptides have been determined in HepG2 hepatoblastoma cells. These peptides are based on the highly specific Pep42 motif, which has been shown to target the glucose‐regulated protein 78 receptors overexpressed and exclusively localized on the cell surface of tumors. In this study, Pep42 was designed to contain varying lengths (3–12) of poly(arginine) sequences to assess their influence on peptide structure and biology. Peptides were effectively synthesized by 9‐fluorenylmethoxycarbonyl‐based solid‐phase peptide synthesis, in which the use of a poly(ethylene glycol) resin provided good yields (14–46%) and crude purities >95% as analyzed by liquid chromatography–mass spectrometry. Peptide structure and biophysical properties were investigated using circular dichroism spectroscopy. Interestingly, peptides displayed secondary structures that were contingent on solvent and length of the poly(arginine) sequences. Peptides exhibited helical and turn conformations, while retaining significant thermal stability. Structure–activity relationship studies conducted by flow cytometry and confocal microscopy revealed that the poly(arginine) derived Pep42 sequences maintained glucose‐regulated protein 78 binding on HepG2 cells while exhibiting cell translocation activity that was contingent on the length of the poly(arginine) strand. In single dose (0.15 mM) and dose‐response (0–1.5 mM) cell viability assays, peptides were found to be nontoxic in human HepG2 liver cancer cells, illustrating their potential as safe cancer‐targeting delivery agents. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
225.
侵袭性真菌感染治疗新进展   总被引:5,自引:0,他引:5  
随着免疫受损人群的增多,近年来侵袭性真菌感染的发生率逐渐升高,由此导致的致病率也逐年上升.如何及时诊断并有效的治疗侵袭性真菌感染已成为临床上面临的挑战之一.该文就侵袭性真菌感染的流行病学、病因学及现有的治疗策略等方面进行综述.  相似文献   
226.
Wnt proteins are secreted glycoproteins that bind to the N-terminal extra-cellular cysteine-rich domain of the Frizzled (Fzd) receptor family. The Fzd receptors can respond to Wnt proteins in the presence of Wnt co-receptors to activate the canonical and non-canonical Wnt pathways. Recent studies indicated that, among the Fzd family, Fzd7 is the Wnt receptor most commonly upregulated in a variety of cancers including colorectal cancer, hepatocellular carcinoma and triple negative breast cancer. Fzd7 plays an important role in stem cell biology and cancer development and progression. In addition, it has been demonstrated that siRNA knockdown of Fzd7, the anti-Fzd7 antibody or the extracellular peptide of Fzd7 (soluble Fzd7 peptide) displayed anti-cancer activity in vitro and in vivo mainly due to the inhibition of the canonical Wnt signaling pathway. Furthermore, pharmacological inhibition of Fzd7 by small interfering peptides or a small molecule inhibitor suppressed β-catenin-dependent tumor cell growth. Therefore, targeted inhibition of Fzd7 represents a rational and promising new approach for cancer therapy.  相似文献   
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Highlights
  • •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
  • •Using patient derived xenograft (PDX) tumors can overcome this limitation.
  • •The large PDX HLA peptidomes expand significantly those of the original biopsies.
  • •The HLA peptidomes of the PDX tumors included many tumor antigens.
  相似文献   
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