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1.
J Ahlberg T Yucel L Eriksson H Glaumann 《Virchows Archiv. B, Cell pathology including molecular pathology》1987,53(2):79-88
Persistent liver nodules (hepatocyte nodules, neoplastic nodules) were produced in rat liver by intermittent feeding with 2-acetylaminofluorene. Dense bodies (secondary lysosomes) were purified and characterized from the nodules. The purity of the dense body fraction was 90%. The levels of various lysosomal enzyme activities were lower in these dense bodies in comparison with dense bodies from control liver. Similarly, protein degradation was 50% lower in dense bodies from liver nodules than in control liver. The number of autophagic vacuoles (AVs) in the nodular tissue increased considerably after 3 h vinblastine treatment. We have taken advantage of this expansion in an effort to isolate these organelles from liver nodules. Autophagic vacuoles have been isolated recently from liver and kidney but not from putatively premalignant liver nodules. Fraction purity of AVs from liver nodules was 95%. As with dense bodies, AVs from nodular tissue displayed lower activities of proteinases and lower rates of protein degradation when compared with their counterparts from normal liver tissue. Accordingly, the lower rate of overall protein degradation in liver nodules can be ascribed to a decrease in lysosomal activity. A diminished autophagic sequestration capacity is the most plausible explanation for the decreased rate of proteolysis in cells. This could conceivably give these nodular cells a growth advantage and assist in their selective outgrowth as well as in their transformation from neoplastic into true cancer cells. 相似文献
2.
Rajesh Kalladan Sebastian Worch Hardy Rolletschek Vokkaliga T. Harshavardhan Lissy Kuntze Christiane Seiler Nese Sreenivasulu Marion S. Röder 《Molecular breeding : new strategies in plant improvement》2013,32(1):71-90
Drought is a major limiting factor for barley production, especially in the primary areas of its cultivation. Wild barley represents a major source of favourable alleles for increasing the genetic variation for multiple traits including resistance to both biotic and abiotic stresses. We used advanced backcross quantitative trait locus (AB-QTL) analysis of a BC3-doubled haploid population developed between the cultivated parent Brenda (Hordeum vulgare ssp. vulgare) and the wild accession HS584 (H. vulgare ssp. spontaneum) to study the contribution of wild barley in improving various agronomic and seed quality traits under post-anthesis drought. The experiment was carried out at two different locations (IPK, Gatersleben and Nordsaat, Böhnshausen) and terminal drought was imposed by withholding water or spraying with potassium iodide at 10 days after flowering under greenhouse or field conditions, respectively. QTL analysis indicated that wild barley contributed favourably to most of the traits studied under both control and drought conditions. A total of seven hot-spot QTL regions with co-localizing QTL for various traits harboured more than 80 % of the stable QTL detected in the present study. For yield and thousand-grain weight and their respective drought tolerance indices, most of the QTL were derived from Brenda. On the other hand, for traits like seed length and seed nitrogen content, all the QTL were contributed by HS584, the parent having higher trait value. A significantly reduced carbon/nitrogen (C/N) ratio in the selected contrasting inferior lines compared to superior ones suggests that C/N ratio could be a potential parameter for screening not just seed quality parameters but also grain weight performance under terminal drought. 相似文献
3.
Increasing temperatures resulting from climate change dramatically impact rice crop production in Asia. Depending on the specific stage of rice development, heat stress reduces tiller/panicle number, decreases grain number per plant and lower grain weight, thus negatively impacting yield formation. Hence improving rice crop tolerance to heat stress in terms of sustaining yield stability under high day temperature (HDT), high night temperature (HNT), or combined high day and night temperature (HDNT) will bolster future food security. In this review article, we highlight the phenological alterations caused by heat and the underlying molecular-physiological and genetic mechanisms operating under different types of heat conditions (HDT, HNT, and HDNT) to understand heat tolerance. Based on our synthesis of HDT, HNT, and HDNT effects on rice yield components, we outline future breeding strategies to contribute to sustained food security under climate change. 相似文献
4.
Ertan Kucuksayan Aysegul Cort Mujgan Timur Evrim Ozdemir Suleyman Gultekin Yucel Prof. Dr. Tomris Ozben 《Journal of cellular biochemistry》2013,114(7):1685-1694
Antioxidants may prevent apoptosis of cancer cells via inhibiting reactive oxygen species (ROS). However, to date no study has been carried out to elucidate the effects of strong antioxidant N‐acetylcysteine (NAC) on Bleomycin induced apoptosis in human testicular cancer (NTERA‐2, NT2) cells. For this reason, we studied the effects of Bleomycin and NAC alone and in combination on apoptotic signaling pathways in NT2 cell line. We determined the cytotoxic effect of bleomycin on NT2 cells and measured apoptosis markers such as Caspase‐3, ‐8, ‐9 activities and Bcl‐2, Bax, Cyt‐c, Annexin V‐FTIC and PI levels in NT2 cells incubated with different agents for 24 h. Early apoptosis was determined using FACS assay. We found half of the lethal dose (LD50) of Bleomycin on NT2 cell viability as 400, 100, and 20 µg/ml after incubations for 24, 48, and 72 h, respectively. Incubation with bleomycin (LD50) and H2O2 for 24 h increased Caspase‐3, ‐8, ‐9 activities, Cyt‐c and Bax levels and decreased Bcl‐2 levels. The concurrent incubation of NT2 cells with bleomycin/H2O2 and NAC (5 mM) for 24 h abolished bleomycin/H2O2‐dependent increases in Caspase‐3, ‐8, ‐9 activities, Bax and Cyt‐c levels and bleomycin/H2O2‐dependent decrease in Bcl‐2 level. Our results indicate that bleomycin/H2O2 induce apoptosis in NT2 cells by activating mitochondrial pathway of apoptosis, while NAC diminishes bleomycin/H2O2 induced apoptosis. We conclude that NAC has antagonistic effects on Bleomycin‐induced apoptosis in NT2 cells and causes resistance to apoptosis which is not a desired effect in eliminating cancer cells. J. Cell. Biochem. 114: 1685–1694, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
5.
Aminothiazoles inhibit RANKL‐ and LPS‐mediated osteoclastogenesis and PGE2 production in RAW 264.7 cells 下载免费PDF全文
Anna Kats Maria Norgård Zenebech Wondimu Catalin Koro Hernán Concha Quezada Göran Andersson Tülay Yucel‐Lindberg 《Journal of cellular and molecular medicine》2016,20(6):1128-1138
Periodontitis is characterized by chronic inflammation and osteoclast‐mediated bone loss regulated by the receptor activator of nuclear factor‐κB (RANK), RANK ligand (RANKL) and osteoprotegerin (OPG). The aim of this study was to investigate the effect of aminothiazoles targeting prostaglandin E synthase‐1 (mPGES‐1) on RANKL‐ and lipopolysaccharide (LPS)‐mediated osteoclastogenesis and prostaglandin E2 (PGE2) production in vitro using the osteoclast precursor RAW 264.7 cells. RAW 264.7 cells were treated with RANKL or LPS alone or in combination with the aminothiazoles 4‐([4‐(2‐naphthyl)‐1,3‐thiazol‐2‐yl]amino)phenol (TH‐848) or 4‐(3‐fluoro‐4‐methoxyphenyl)‐N‐(4‐phenoxyphenyl)‐1,3‐thiazol‐2‐amine (TH‐644). Aminothiazoles significantly decreased the number of multinucleated tartrate‐resistant acid phosphatase (TRAP)‐positive osteoclast‐like cells in cultures of RANKL‐ and LPS‐stimulated RAW 264.7 cells, as well as reduced the production of PGE2 in culture supernatants. LPS‐treatment induced mPGES‐1 mRNA expression at 16 hrs and the subsequent PGE2 production at 72 hrs. Conversely, RANKL did not affect PGE2 secretion but markedly reduced mPGES‐1 at mRNA level. Furthermore, mRNA expression of TRAP and cathepsin K (CTSK) was reduced by aminothiazoles in RAW 264.7 cells activated by LPS, whereas RANK, OPG or tumour necrosis factor α mRNA expression was not significantly affected. In RANKL‐activated RAW 264.7 cells, TH‐848 and TH‐644 down‐regulated CTSK but not TRAP mRNA expression. Moreover, the inhibitory effect of aminothiazoles on PGE2 production was also confirmed in LPS‐stimulated human peripheral blood mononuclear cell cultures. In conclusion, the aminothiazoles reduced both LPS‐ and RANKL‐mediated osteoclastogenesis and PGE2 production in RAW 264.7 cells, suggesting these compounds as potential inhibitors for treatment of chronic inflammatory bone resorption, such as periodontitis. 相似文献
6.
Anna Kats Natalija Gerasimcik Tuomas Nreoja Jonas Nederberg Simon Grenlv Ekaterina Lagnhed Suchita Desai Gran Andersson Tülay Yucel‐Lindberg 《Journal of cellular and molecular medicine》2019,23(2):1152-1163
Inflammatory mediator prostaglandin E2 (PGE2) contributes to bone resorption in several inflammatory conditions including periodontitis. The terminal enzyme, microsomal prostaglandin E synthase‐1 (mPGES‐1) regulating PGE2 synthesis is a promising therapeutic target to reduce inflammatory bone loss. The aim of this study was to investigate effects of mPGES‐1 inhibitors, aminothiazoles TH‐848 and TH‐644, on PGE2 production and osteoclastogenesis in co‐cultures of periodontal ligament (PDL) and osteoclast progenitor cells RAW 264.7, stimulated by lipopolysaccharide (LPS), and bone resorption in RANKL‐mediated peripheral blood mononuclear cells (PBMCs). PDL and RAW 264.7 cells were cultured separately or co‐cultured and treated with LPS alone or in combination with aminothiazoles. Multinucleated cells stained positively for tartrate‐resistant acid phosphatase (TRAP) were scored as osteoclast‐like cells. Levels of PGE2, osteoprotegerin (OPG) and interleukin‐6, as well as mRNA expression of mPGES‐1, OPG and RANKL were analysed in PDL cells. PBMCs were treated with RANKL alone or in combination with aminothiazoles. TRAP‐positive multinucleated cells were analysed and bone resorption was measured by the CTX‐I assay. Aminothiazoles reduced LPS‐stimulated osteoclast‐like cell formation both in co‐cultures and in RAW 264.7 cells. Additionally, aminothiazoles inhibited PGE2 production in LPS‐stimulated cultures, but did not affect LPS‐induced mPGES‐1, OPG or RANKL mRNA expression in PDL cells. In PBMCs, inhibitors decreased both osteoclast differentiation and bone resorption. In conclusion, aminothiazoles reduced the formation of osteoclast‐like cells and decreased the production of PGE2 in co‐cultures as well as single‐cell cultures. Furthermore, these compounds inhibited RANKL‐induced bone resorption and differentiation of PBMCs, suggesting these inhibitors for future treatment of inflammatory bone loss such as periodontitis. 相似文献
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8.
Nese Sari Kathryn E. Fisher Philip N. Bryan John Orban 《Biomolecular NMR assignments》2007,1(2):209-211
Main chain assignments are described for a 266-residue subtilisin mutant, Sbt70, in its 35 kDa complex with an N-terminal
prodomain. The assignments provide the basis for understanding how the prodomain assists folding of subtilisin at a residue-specific
level. 相似文献
9.
Bulut V Ilhan F Yucel AY Onal S Ilhan Y Godekmerdan A 《Memórias do Instituto Oswaldo Cruz》2001,96(5):669-671
Hydatid disease is caused by Echinococcus granulosus. In this study, we aimed to investigate the benefit of monitoring cases with hydatid cyst by means of immune components in patients in a long-term follow-up after surgery. Eighty-four preoperative and postoperative serum samples from 14 cases undergoing surgery for hydatid disease were evaluated in terms of immune parameters, such as total and specific IgE, IgG, IgM, IgA and complement. Total and specific IgE were determined by ELISA. Specific IgG levels were measured by indirect hemagglutination.Total IgG, IgM, IgA and complement (C3 and C4) were detected by nephelometry. Imaging studies were also carried out during the follow-up. In none of the patients hydatid cysts were detected during the follow-up. Total IgE levels in the sera of the patients decreased to normal six months after surgery. Although specific IgE against echinococcal antigens decreased one year after operation, levels were still significantly high. There were no changes in the levels of anti-Echinococcus IgG and total IgG in follow-up period. Additionally, other parameters, such as IgA, IgM, C3 and C4, were not affected. 相似文献
10.
Human serum butyrylcholinesterase (BChE) has been converted into a stable but less active desensitized form when heated at
45°C for 24 h. The desensitized BChE follows Michaelis-Menten kinetics, whereas native enzyme exhibits slightly negative cooperativity
with respect to butyrylthiocholine binding. In this study, we investigated the effects of Ni2+, Co2+, and Mn2+ on the desensitized BChE. It is found that all three ions were noncompetitive inhibitors of the desensitized BChE, and K
i
values have been determined as 7.816±1.060 mM, 48.722±4.635 mM, and 84.795±5.249 mM for Ni2+, Co2+, and Mn2+, respectively. In our previous study, these ions were linear mixed-type inhibitors of the native BChE. This finding confirms
that desensitized BChE changes to a different conformation than native BChE. From the comparison of K
i
values of the trace elements, it can be said that Ni2+ is a more effective inhibitor of the desensitized BChE than Co2+ and Mn2+. 相似文献