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81.
Regulation of chromatin structure is an essential component of the DNA damage response (DDR), which effectively preserves the integrity of DNA by a network of multiple DNA repair and associated signaling pathways. Within the DDR, chromatin is modified and remodeled to facilitate efficient DNA access, to control the activity of repair proteins and to mediate signaling. The mammalian ISWI family has recently emerged as one of the major ATP-dependent chromatin remodeling complex families that function in the DDR, as it is implicated in at least 3 major DNA repair pathways: homologous recombination, non-homologous end-joining and nucleotide excision repair. In this review, we discuss the various manners through which different ISWI complexes regulate DNA repair and how they are targeted to chromatin containing damaged DNA. 相似文献
82.
Insecticidal Metabolites from the Rhizomes of Veratrum album against Adults of Colorado Potato Beetle,Leptinotarsa decemlineata
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Tuba Aydin Ahmet Cakir Cavit Kazaz Neslihan Bayrak Yasin Bayir Yavuz Taşkesenligil 《化学与生物多样性》2014,11(8):1192-1204
The dried rhizomes of Veratrum album were individually extracted with CHCl3, acetone, and NH4OH/benzene to test the toxic effects against the Colorado potato beetle, Leptinotarsa decemlineata, which is an important agricultural pest. Fifteen compounds in various amounts were isolated from the extracts using column and thin‐layer chromatography. The chemical structures of 14 compounds were characterized as octacosan‐1‐ol ( 1 ), β‐sitosterol ( 2 ), stearic acid ( 3 ), diosgenin ( 4 ), resveratrol ( 5 ), wittifuran X ( 6 ), oxyresveratrol ( 7 ), β‐sitosterol 3‐O‐β‐D ‐glucopyranoside ( 8 ), diosgenin 3‐O‐α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyronoside ( 9 ), oxyresveratrol 3‐O‐β‐D ‐glucopyranoside ( 10 ), jervine ( 11 ), pseudojervine ( 13 ), 5,6‐dihydro‐1‐hydroxyjervine ( 14 ), and saccharose ( 15 ) using UV, IR, MS, 1H‐ and 13C‐NMR, and 2D‐NMR spectroscopic methods. However, the chemical structure of 12 , an oligosaccharide, has not fully been elucidated. Compounds 4, 6, 9 , and 10 were isolated from V. album rhizomes for the first time in the current study. The toxic effects of three extracts (acetone, CHCl3, and NH4OH/benzene) and six metabolites, 2, 2 + 4, 5, 7, 8 , and 11 , were evaluated against the Colorado potato beetle. The assay revealed that all three extracts, and compounds 7, 8 , and 11 exhibited potent toxic effects against this pest. This is the first report on the evaluation of the toxic effects of the extracts and secondary metabolites of V. album rhizomes against L. decemlineata. Based on these results, it can be concluded that the extracts can be used as natural insecticides. 相似文献
83.
Background
Large-scale compilation of gene expression microarray datasets across diverse biological phenotypes provided a means of gathering a priori knowledge in the form of identification and annotation of bimodal genes in the human and mouse genomes. These switch-like genes consist of 15% of known human genes, and are enriched with genes coding for extracellular and membrane proteins. It is of interest to determine the prediction potential of bimodal genes for class discovery in large-scale datasets. 相似文献84.
85.
Agar Guleray Taspinar Mahmut Sinan Yildirim Ertan Aydin Murat Yuce Merve 《Journal of Plant Growth Regulation》2020,39(2):897-904
Journal of Plant Growth Regulation - Heavy metal pollution, which is one of the most important environmental problems, has a significant effect on plant growth and development. Plants influence all... 相似文献
86.
Plasma and inflammatory fluid kininogen levels, and blood and inflammatory fluid free kinin levels were determined in rats 24 h after the injection of carrageenin into an air pouch. Plasma T-kininogen levels increased 7-fold. In the inflammatory fluid levels reached 8 μg/ml. Blood levels of free kinin showed a 5-fold increase. The kinins were identified on HPLC as T-kinin (Ile-Ser-bradykinin) and bradykinin, 63 and 37%, respectively. These results indicate for the first time that free T-kinin as well as bradykinin is released during an inflammatory response in rat and confirms our previous finding that T-kininogen may be a major acutephase protein in inflammation.
T-kinin T-kininogen Bradykinin Inflammation Acute-phase protein Carrageenin 相似文献
87.
Trichotoxin A40. Purification by counter-current distribution and sequencing of isolated fragments 总被引:2,自引:0,他引:2
The isolation of the membrane-modifying polypeptide antibiotics from the mycelium of Trichoderma viride 5242 was optimized via extraction with dichloromethane and chromatography on Sephadex LH-20. The components trichotoxin A40 and A50 were separated from each other and purified by multiplicative counter-current distribution. The sequence of proteinase-resistant trichotoxin A40 was determined by combined gas chromatography and mass spectrometry of three isolated N-acetylated dodecapeptides and two N-prolylhexapeptides obtained after selective trifluoroacetolysis. Including amino acid exchanges due to natural microheterogeneity, the sequence is Ac-Aib-Gly(LAla)-Aib-LLeu-Aib-LGln-Aib-Aib-Aib(LAla )-LAla-Aib-Aib-LPro-LLeu -Aib-DIva(Aib)-LGlu-LValol. In contrast to the eicosapeptide alamethicin, trichotoxin A40 contains only 18 residues, with a higher proportion of alpha-aminoisobutyric acid (Aib), C-terminal L-valinol (Vol), one D-isovaline (Iva) and no proline at the N-terminal part. 相似文献
88.
Xinbo Yang Erkan Aydin Hang Xu Jingxuan Kang Mohamed Hedhili Wenzhu Liu Yimao Wan Jun Peng Christian Samundsett Andres Cuevas Stefaan De Wolf 《Liver Transplantation》2018,8(20)
Minimizing carrier recombination at contact regions by using carrier‐selective contact materials, instead of heavily doping the silicon, has attracted considerable attention for high‐efficiency, low‐cost crystalline silicon (c‐Si) solar cells. A novel electron‐selective, passivating contact for c‐Si solar cells is presented. Tantalum nitride (TaN x ) thin films deposited by atomic layer deposition are demonstrated to provide excellent electron‐transporting and hole‐blocking properties to the silicon surface, due to their small conduction band offset and large valence band offset. Thin TaNx interlayers provide moderate passivation of the silicon surfaces while simultaneously allowing a low contact resistivity to n‐type silicon. A power conversion efficiency (PCE) of over 20% is demonstrated with c‐Si solar cells featuring a simple full‐area electron‐selective TaNx contact, which significantly improves the fill factor and the open circuit voltage (Voc) and hence provides the higher PCE. The work opens up the possibility of using metal nitrides, instead of metal oxides, as carrier‐selective contacts or electron transport layers for photovoltaic devices. 相似文献
89.
90.
Aydin Ece Bekir Sami Uyamik Akin IŞcan Pelin Ertan M. Ramazan Yiğitolu 《Biological trace element research》1997,59(1-3):31-39
In order to evaluate serum copper and zinc status in children with iron deficiency anemia (IDA), 60 children with IDA aged
1–14 yr and 64 healthy children as controls aged 1–14 yr were included the study. Serum copper levels were higher in children
with IDA (189 ± 49 (Μg/dL) than those of controls (163 ± 37 Μg/dL) (p = 0.001). Serum zinc levels were lower in the patient group (109 ± 59 Μg/dL) than those of control subjects (135 ± 56 Μg/dL)
(p = 0.017). In addition, there were statistically significant negative correlations between hematological parameters and serum
copper levels in the patient group, but not in controls. No correlation between hematological parameters and serum zinc levels
were found in both patient and control groups, except positive correlation between mean corpuscular volume (MCV) and serum
zinc level in patients.
It was concluded that at the time of managing children with IDA, zinc deficiency must be borne in mind and if necessary treatment
should be initiated with zinc. 相似文献