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91.
Kim MH Park SC Kim JY Lee SY Lim HT Cheong H Hahm KS Park Y 《Biochemical and biophysical research communications》2006,346(3):681-686
Potide-G, a small (5578.9 Da) antimicrobial peptide, was isolated from potato tubers (Solanum tuberosum L. cv. Golden Valley) through extraction of the water-soluble fraction, dialysis, ultrafiltration and DEAE-cellulose and C18 reverse-phase high performance liquid chromatography. This antimicrobial peptide was heat-stable and almost completely suppressed the proteolytic activity of trypsin, chymotrypsin and papain, with no hemolytic activity. In addition, potide-G potently inhibited growth of a variety of bacterial (Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Clavibacter michiganense subsp. michiganinse) and fungal (Candida albicans and Rhizoctonia solani) strains. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry revealed that the N-terminal sequence (residues from 1 to 11) of the protein is identical to that of potato proteinase inhibitor, a member of the Kunitz superfamily. And like other members of this class of protease inhibitor, potide-G may have a number of beneficial and therapeutic uses. 相似文献
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93.
Justin Perry Linda A. Rymarquis Monica Accerbi Pamela J. Green Simon Prochnik Erika Lindquist Cheong Xin Chan Charles Yarish Senjie Lin Yunyun Zhuang Nicolas A. Blouin Susan H. Brawley 《Journal of phycology》2012,48(4):883-896
Little is known about the genetic and biochemical mechanisms that underlie red algal development, for example, why the group failed to evolve complex parenchyma and tissue differentiation. Here we examined expressed sequence tag (EST) data from two closely related species, Porphyra umbilicalis (L.) J. Agardh and P. purpurea (Roth) C. Agardh, for conserved developmental regulators known from model eukaryotes, and their expression levels in several developmental stages. Genes for most major developmental families were present, including MADS‐box and homeodomain (HD) proteins, SNF2 chromatin‐remodelers, and proteins involved in sRNA biogenesis. Some of these genes displayed altered expression correlating with different life history stages or cell types. Notably, two ESTs encoding HD proteins showed eightfold higher expression in the P. purpurea sporophyte (conchocelis) than in the gametophyte (blade), whereas two MADS domain‐containing paralogs showed significantly different patterns of expression in the conchocelis and blade respectively. These developmental gene families do not appear to have undergone the kinds of dramatic expansions in copy number found in multicellular land plants and animals, which are important for regulating developmental processes in those groups. Analyses of small RNAs did not validate the presence of miRNAs, but homologs of Argonaute were present. In general, it appears that red algae began with a similar molecular toolkit for directing development as did other multicellular eukaryotes, but probably evolved altered roles for many key proteins, as well as novel mechanisms yet to be discovered. 相似文献
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Although macrophages and other immune system cells, especially T cells, have been shown to play disease-promoting roles in atherosclerosis, less is known about the role of antigen presenting cells. Functional, immune stimulating dendritic cells (DCs) have recently been detected in aortic intima, the site of origin of atherosclerosis. We had compared DCs with macrophages in mice with experimental atherosclerosis, to clearly define cell types by developmental and functional criteria. This review summarizes recent advances in studies of DCs in humans and in mouse models of atherosclerosis, as well as providing a simple strategy to measure regulatory T (Treg) cells in the mouse aorta. 相似文献
96.
Association of GNLY Genetic Polymorphisms with Chronic Liver Disease in a Korean Population 总被引:1,自引:0,他引:1
Granulysin (GNLY) is found in cytotoxic granules of cytolytic T lymphocytes and natural killer (NK) cells, which are critical for hepatitis B virus (HBV) clearance. GNLY cytotoxicity plays an important role in the defense against viruses or intracellular bacteria. We hypothesized that genetic variation in the GNLY gene could affect the resistance of hosts against HBV infection. We compared the distribution frequencies of GNLY polymorphisms between an HBV-induced chronic liver disease (CLD) group and a spontaneous recovery (SR) control group to determine whether GNLY polymorphisms play a role in HBV clearance. A total of 117 patients in the SR group and 230 patients in the CLD group were enrolled. Samples derived from complex infections, including hepatitis C and human immunodeficiency virus, and those associated with insufficient clinical information (10 samples in SR and 24 samples in CLD) were excluded from the study. The final analysis included 107 SR and 206 CLD samples. DNA was extracted from peripheral blood, and GNLY genotypes were determined by the GoldenGate(?) method. The genotype distribution of the single-nucleotide polymorphisms (SNPs) rs2886767 (C>T), rs1561285 (G>C), and rs11127 (T>C) were significantly different between the SR and CLD groups in a recessive model (p<0.015). These three SNPs were in a complete linkage disequilibrium (LD) block. Diplotype distributions of haplotype (HT) 1 (C-G-T) and HT2 (T-C-C) were significantly different between the SR and CLD groups in a recessive model (p=0.025) and a dominant model (p=0.008). All p-values remained significant after multiple comparisons. GNLY polymorphism genotypes and diplotypes were associated with the chronicity of HBV. These data suggested that genetic variation of GNLY may be an important factor in HBV clearance through the CD8+ T or NK cell-mediated removal of HBV-infected cells from the host. 相似文献
97.
Foong Ying Wong Natalia Liem Chen Xie Fui Leng Yan Wing Cheong Wong Lingzhi Wang Wei-Peng Yong 《PloS one》2012,7(12)
Although gemcitabine is highly active in several cancer types, intrinsic and acquired drug resistance remains a major challenge. Overexpression of Bcl-2 has been associated with gemcitabine resistance. The aim of this study is to determine whether gossypol can overcome gemcitabine resistance in cell lines with high level of Bcl-2 expression in combination drug therapy. Our study demonstrated that in 10 cell lines derived from different cancers, high Bcl-2 baseline expression was observed in cell lines that were resistant to gemcitabine (GEM-R). Furthermore, synergistic effect of combination therapy was observed in gemcitabine-resistant (GEM-R) cell lines with high Bcl-2 expression, but not in a gemcitabine-sensitive (GEM-S) cell lines regardless of Bcl-2 expression. Gossypol treatment resulted in the decrease of anti-apoptotic genes such as Bcl-2 and Bcl-xl and an upregulation of the pro-apoptotic gene, Noxa. Furthermore, the addition of gossypol to gemcitabine resulted in lower expressions of anti-apoptotic genes compared to gemcitabine alone. Gene expression profiling in GEM-R and GEM-S cell lines suggest that anti-apoptotic genes such as pAkt and PI3KR2 may play important role in gemcitabine resistance, while pro-apoptotic Bcl-2 related genes (Bad, Caspase-6 and Calpain-1) may regulate synergistic interaction in combination therapy. 相似文献
98.
Park Y Kim MH Park SC Cheong H Jang MK Nah JW Hahm KS 《Journal of microbiology and biotechnology》2008,18(10):1729-1734
Chitosan, a cationic polysaccharide, has been widely used as a dietary supplement and in a variety of pharmacological and biomedical applications. The antifungal activity and mechanism of action of low molecular weight water-soluble chitosan (LMWS-chitosan) were studied in fungal cells and vesicles containing various compositions of fungal lipids. LMWS-chitosan showed strong antifungal activity against various pathogenic yeasts and hyphae-forming fungi but no hemolytic activity or cytotoxicity against mammalian cells. The degree of calcein leakage was assessed on the basis of lipid composition (PC/CH; 10:1, w/w). Our result showing that LMWS-chitosan interacts with liposomes demonstrated that chitosan induces leakage from zwitterionic lipid vesicles. Confocal microscopy revealed that LMWS-chitosan was located in the plasma membrane. Finally, scanning electron microscopy revealed that LMWS-chitosan causes significant morphological changes on fungal surfaces. Its potent antibiotic activity suggests that LMWS-chitosan is an excellent candidate as a lead compound for the development of novel anti-infective agents. 相似文献
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100.
MCL1 expression has been found to be up-regulated during infection with virulent Mycobacterium tuberculosis. We investigated the genetic polymorphisms in MCL1 as potential candidate gene for a host genetic study of clinical TB infection. We have sequenced exons and their boundaries of MCL1, including the 1.5 kb promoter region, to identify polymorphisms, and eight polymorphisms were identified. The genetic associations of polymorphisms in MCL1 with clinical TB patients (n=486) and normal controls (n=370) were analyzed. Using statistical analyses, one common promoter polymorphism (MCL1- 324C > A) which is absolutely linked with three other SNPs in the promoter and 3'UTR regions, were found to be significantly associated with increased risk of clinical TB disease. The frequency of the A-bearing genotype of -324C > A was higher in clinical TB patients than in normal controls (P=0.0008, OR= 1.68). Our findings suggest that polymorphisms in MCL1 might be one of genetic factors for the risk of clinical tuberculosis development. 相似文献