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991.
992.
The genome size of the pine fusiform rust pathogen Cronartium quercuum f.sp. fusiforme (Cqf) was determined by flow cytometric analysis of propidium iodide-stained, intact haploid pycniospores with haploid spores of two genetically well characterized fungal species, Sclerotinia sclerotiorum and Puccinia graminis f.sp. tritici, as size standards. The Cqf haploid genome was estimated at ~90 Mb, similar to other Pucciniales species for which reference genome sequences are available. Twenty-three Cqf pycniospore samples were compared that comprised three samples obtained from naturally occurring pine galls and 20 samples obtained after artificial inoculation with parental isolates and their progeny. Significant variation in genome size (>10% of mean) was detected among unrelated as well as sibling Cqf samples. The unexpected plasticity in Cqf genome size observed among sibling samples is likely to be driven by meiosis between parental genomes that differ in size. 相似文献
993.
994.
Jun-Gu Kang Sungjin Ko Heung-Chul Kim Sung-Tae Chong Terry A. Klein Jeong-Byoung Chae Yong-Sun Jo Kyoung-Seong Choi Do-Hyeon Yu Bae-Keun Park Jinho Park Joon-Seok Chae 《The Korean journal of parasitology》2016,54(1):87-91
Deer serve as reservoirs of tick-borne pathogens that impact on medical and veterinary health worldwide. In the Republic of Korea, the population of Korean water deer (KWD, Hydropotes inermis argyropus) has greatly increased from 1982 to 2011, in part, as a result of reforestation programs established following the Korean War when much of the land was barren of trees. Eighty seven Haemaphysalis flava, 228 Haemaphysalis longicornis, 8 Ixodes nipponensis, and 40 Ixodes persulcatus (21 larvae, 114 nymphs, and 228 adults) were collected from 27 out of 70 KWD. A total of 89/363 ticks (266 pools, 24.5% minimum infection rate) and 5 (1.4%) fed ticks were positive for Anaplasma phagocytophilum using nested PCR targeting the 16S rRNA and groEL genes, respectively. The 16S rRNA gene fragment sequences of 88/89 (98.9%) of positive samples for A. phagocytophilum corresponded to previously described gene sequences from KWD spleen tissues. The 16S rRNA gene fragment sequences of 20/363 (5.5%) of the ticks were positive for A. bovis and were identical to previously reported sequences. Using the ITS specific nested PCR, 11/363 (3.0%) of the ticks were positive for Bartonella spp. This is the first report of Anaplasma and Bartonella spp. detected in ticks collected from KWD, suggesting that ticks are vectors of Anaplasma and Bartonella spp. between reservoir hosts in natural surroundings. 相似文献
995.
996.
Organellar nuclear-encoded proteins can be mitochondrial, chloroplastic or localized in both mitochondria and chloroplasts. Most of the determinants for organellar targeting are localized in the N-terminal part of the proteins, which were therefore analyzed in Arabidopsis thaliana. The mitochondrial, chloroplastic and dual N-terminal sequences have an overall similar composition. However, Arg is rare in the first 20 residues of chloroplastic and dual sequences, and Ala is more frequent at position 2 of these two types of sequence as compared to mitochondrial sequences. According to these observations, mutations were performed in three dual targeted proteins and analyzed by in vitro import into isolated mitochondria and chloroplasts. First, experiments performed with wild-type proteins suggest that the binding of precursor proteins to mitochondria is highly efficient, whereas the import and processing steps are more efficient in chloroplasts. Moreover, different processing sites are recognized by the mitochondrial and chloroplastic processing peptidases. Second, the mutagenesis approach shows the positive role of Arg residues for enhancing mitochondrial import or processing, as expected by the in silico analysis. By contrast, mutations at position 2 have dramatic and unpredicted effects, either enhancing or completely abolishing import. This suggests that the nature of the second amino acid residue of the N-terminal sequence is essential for the import of dual targeted sequences. 相似文献
997.
Hampton CR Shimamoto A Rothnie CL Griscavage-Ennis J Chong A Dix DJ Verrier ED Pohlman TH 《American journal of physiology. Heart and circulatory physiology》2003,285(2):H866-H874
We investigated the role of inducible heat shock proteins 70.1 and 70.3 (HSP70.1 and HSP70.3, respectively) in myocardial ischemic preconditioning (IP) in mice. Wild-type (WT) mice and HSP70.1- and HSP70.3-null [HSP70.1/3(-/-)] mice were subjected to IP and examined 24 h later during the late phase of protection. IP significantly increased steady-state levels of HSP70.1 and HSP70.3 mRNA and expression of inducible HSP70 protein in WT myocardium. To assess protection against tissue injury, mice were subjected to 30 min of regional ischemia and 3 h of reperfusion. In WT mice, IP reduced infarct size by 43% compared with sham IP-treated mice. In contrast, IP did not reduce infarct size in HSP70.1/3(-/-) mice. Absence of inducible HSP70.1 and HSP70.3 had no effect, however, on classical or early-phase protection produced by IP, which significantly reduced infarct size in HSP70.1/3(-/-) mice. We conclude that inducible HSP70.1 and HSP70.3 are required for late-phase protection against infarction following IP in mice. 相似文献
998.
Raymond C.S. Seet Chung-Yung J. Lee Erle C.H. Lim June J.H. Tan Amy M.L. Quek Wan-Ling Chong Woan-Foon Looi Shan-Hong Huang Huansong Wang Yiong-Huak Chan Barry Halliwell 《Free radical biology & medicine》2010,48(4):560-566
Oxidative damage has been implicated in the pathogenesis of Parkinson disease (PD) but the literature data are confusing. Using products of lipid and DNA oxidation measured by accurate methods, we assessed the extent of oxidative damage in PD patients. The levels of plasma F2-isoprostanes (F2-IsoPs), hydroxyeicosatetraenoic acid products (HETEs), cholesterol oxidation products, neuroprostanes (F4-NPs), phospholipase A2 (PLA2) and platelet activating factor–acetylhydrolase (PAF-AH) activities, urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG), and serum high-sensitivity C-reactive protein were compared in 61 PD patients and 61 age-matched controls. The levels of plasma F2-IsoPs, HETEs, 7β-and 27-hydroxycholesterol, 7-ketocholesterol, F4-NPs, and urinary 8-OHdG were elevated, whereas the levels of plasma PLA2 and PAF-AH activities were lower, in PD patients compared to controls (p < 0.05). The levels of plasma F2-IsoPs, HETEs, and urinary 8-OHdG were higher in the early stages of PD (p trend < 0.05). There was a significant negative correlation between the cumulative intake of levodopa and urinary 8-OHdG (r = ?0.305, p = 0.023) and plasma total HETEs (r = ?0.285, p = 0.043). Oxidative damage markers are systemically elevated in PD, which may give clues about the relation of oxidative damage to the onset and progression of PD. 相似文献
999.
Wetlands Ecology and Management - The Domaine de la Palissade is a 700-ha nature reserve located at the mouth of the Rhône river in southern France. Since 2006, the tidal wetlands have been... 相似文献
1000.
Ecosystems - Fire suppression has increased fuel load and the risk of catastrophic wildfire in forest and woodland ecosystems across the Western United States. In an effort to reduce fuel load and... 相似文献