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271.
Trichoderma species--opportunistic, avirulent plant symbionts 总被引:25,自引:0,他引:25
Trichoderma spp. are free-living fungi that are common in soil and root ecosystems. Recent discoveries show that they are opportunistic, avirulent plant symbionts, as well as being parasites of other fungi. At least some strains establish robust and long-lasting colonizations of root surfaces and penetrate into the epidermis and a few cells below this level. They produce or release a variety of compounds that induce localized or systemic resistance responses, and this explains their lack of pathogenicity to plants. These root-microorganism associations cause substantial changes to the plant proteome and metabolism. Plants are protected from numerous classes of plant pathogen by responses that are similar to systemic acquired resistance and rhizobacteria-induced systemic resistance. Root colonization by Trichoderma spp. also frequently enhances root growth and development, crop productivity, resistance to abiotic stresses and the uptake and use of nutrients. 相似文献
272.
Background
It has been reported that following rehabilitation, only 7% of stroke survivors are able to walk at a level commensurate with community participation. Previous research indicates that treadmill and overground walking training can improve walking capacity in people living in the community after stroke. The main objectives of the AMBULATE trial are to determine (i) whether a 4-month treadmill walking program is more effective than a 2-month program, compared to control, in improving walking capacity, health and community participation and (ii) the "threshold" walking speed that results in sufficient walking capacity that makes walking self-sustaining. 相似文献273.
Dorard C de Thonel A Collura A Marisa L Svrcek M Lagrange A Jego G Wanherdrick K Joly AL Buhard O Gobbo J Penard-Lacronique V Zouali H Tubacher E Kirzin S Selves J Milano G Etienne-Grimaldi MC Bengrine-Lefèvre L Louvet C Tournigand C Lefèvre JH Parc Y Tiret E Fléjou JF Gaub MP Garrido C Duval A 《Nature medicine》2011,17(10):1283-1289
Heat shock proteins (HSPs) are necessary for cancer cell survival. We identified a mutant of HSP110 (HSP110ΔE9) in colorectal cancer showing microsatellite instability (MSI CRC), generated from an aberrantly spliced mRNA and lacking the HSP110 substrate-binding domain. This mutant was expressed at variable levels in almost all MSI CRC cell lines and primary tumors tested. HSP110ΔE9 impaired both the normal cellular localization of HSP110 and its interaction with other HSPs, thus abrogating the chaperone activity and antiapoptotic function of HSP110 in a dominant-negative manner. HSP110ΔE9 overexpression caused the sensitization of cells to anticancer agents such as oxaliplatin and 5-fluorouracil, which are routinely prescribed in the adjuvant treatment of people with CRC. The survival and response to chemotherapy of subjects with MSI CRCs was associated with the tumor expression level of HSP110ΔE9. HSP110 may thus constitute a major determinant for both prognosis and treatment response in CRC. 相似文献
274.
Ada H. V. Repetto-Llamazares Roy H. Larsen Sebastian Patzke Karianne G. Fleten David Didierlaurent Alexandre Pichard Jean Pierre Pouget Jostein Dahle 《PloS one》2015,10(6)
177Lu-DOTA-HH1 (177Lu-HH1) is a novel anti-CD37 radioimmunoconjugate developed to treat non-Hodgkin lymphoma. Mice with subcutaneous Ramos xenografts were treated with different activities of 177Lu-HH1, 177Lu-DOTA-rituximab (177Lu-rituximab) and non-specific 177Lu-DOTA-IgG1 (177Lu-IgG1) and therapeutic effect and toxicity of the treatment were monitored. Significant tumor growth delay and increased survival of mice were observed in mice treated with 530 MBq/kg 177Lu-HH1 as compared with mice treated with similar activities of 177Lu-rituximab or non-specific 177Lu-IgG1, 0.9% NaCl or unlabeled HH1. All mice injected with 530 MBq/kg of 177Lu-HH1 tolerated the treatment well. In contrast, 6 out of 10 mice treated with 530 MBq/kg 177Lu-rituximab experienced severe radiation toxicity. The retention of 177Lu-rituximab in organs of the mononuclear phagocyte system was longer than for 177Lu-HH1, which explains the higher toxicity observed in mice treated with 177Lu-rituximab. In vitro internalization studies showed that 177Lu-HH1 internalizes faster and to a higher extent than 177Lu-rituximab which might be the reason for the better therapeutic effect of 177Lu-HH1. 相似文献
275.
We consider a population subdivided into two demes connected by migration in which selection acts in opposite direction. We explore the effects of recombination and migration on the maintenance of multilocus polymorphism, on local adaptation, and on differentiation by employing a deterministic model with genic selection on two linked diallelic loci (i.e., no dominance or epistasis). For the following cases, we characterize explicitly the possible equilibrium configurations: weak, strong, highly asymmetric, and super-symmetric migration, no or weak recombination, and independent or strongly recombining loci. For independent loci (linkage equilibrium) and for completely linked loci, we derive the possible bifurcation patterns as functions of the total migration rate, assuming all other parameters are fixed but arbitrary. For these and other cases, we determine analytically the maximum migration rate below which a stable fully polymorphic equilibrium exists. In this case, differentiation and local adaptation are maintained. Their degree is quantified by a new multilocus version of $F_\mathrm{ST}$ and by the migration load, respectively. In addition, we investigate the invasion conditions of locally beneficial mutants and show that linkage to a locus that is already in migration-selection balance facilitates invasion. Hence, loci of much smaller effect can invade than predicted by one-locus theory if linkage is sufficiently tight. We study how this minimum amount of linkage admitting invasion depends on the migration pattern. This suggests the emergence of clusters of locally beneficial mutations, which may form ‘genomic islands of divergence’. Finally, the influence of linkage and two-way migration on the effective migration rate at a linked neutral locus is explored. Numerical work complements our analytical results. 相似文献
276.
New Zealand is the southernmost limit of the common dolphin's (genus Delphinus) distribution in the Pacific Ocean. In this area, common dolphins occur in both coastal and oceanic habitats, exhibit seasonal and resident occurrence, and present high morphological variability. Here we investigated the population structure and the taxonomic identity of common dolphins (Delphinus sp.) within New Zealand waters using 14 microsatellite loci, 577 bp of the mtDNA control region, and 1,120 bp of the mtDNA cytochrome b gene across 90 individuals. We found high genetic variability and evidence of population expansion. Phylogenetic analyses conducted to clarify the taxonomic status of New Zealand common dolphins did not show any clustering reflecting geographic origin or morphotypes. The microsatellite analysis showed genetic differentiation between Coastal and Oceanic putative populations, while mtDNA revealed significant genetic differentiation only between the Hauraki Gulf and other putative groups. Our results suggest that differences in habitat choice and possible female site fidelity may play a role in shaping population structure of New Zealand common dolphins. 相似文献
277.
A high prevalence of epilepsies in specific immunological diseases suggests that the immune system may play a role in the pathogenesis of epilepsy or might be associated with it. In this study the frequency of anticardiolipin antibodies (aCL), antinuclear antibodies (ANA) and anti-beta2-glycoprotein I antibodies (anti-beta2-GPI) in 40 children with epilepsy and in 38 healthy subjects was determined. Positive aCL was found in 3 patients, and anti-beta2-GPI in 1 patient. In control group they were negative. ANA antibodies were negative in both groups. Duration of epilepsy < 1 year was observed in all three patients with positive aCL. No statistically significant difference was found concerning the presence of these antibodies between patients and controls. There was no statistically significant correlation of age, sex, age at the onset of epilepsy, duration of epilepsy, type of epilepsy, seizure frequency or specific antiepileptic medications with the presence of any measured antibodies. 相似文献
278.
Mangrove sediment is well known for its susceptibility to anthropogenic pollution, including polycyclic aromatic hydrocarbons
(PAHs), but knowledge of the sediment microbial community structure with regards to exposure to PAHs is limited. The study
aims to assess the effects of PAHs on the bacterial community of mangrove sediment using both 16s rDNA polymerase chain reaction-denaturing
gradient gel electrophoresis (PCR-DGGE) and traditional enrichment methods. Both the exposure time and the PAH concentration
reduced the microbial diversity, as determined by the DGGE bands. Although PAHs could act as carbon sources for microorganisms,
PAHs, at a concentration as low as 20 mg l−1, posed a toxic effect to the microbial community. Sequencing of DGGE bands showed that marine bacteria from the genera of
Vibrio, Roseobacter, and Ferrimonas were most abundant after PAH exposure, which suggests that both marine and terrestrial bacteria coexisted in the mangrove
sediment, but that the marine microbes were more difficult to isolate using the traditional culture method. DGGE determination
further demonstrated that the consistency among triplicates of the enriched consortia was significantly less than that of
the sediment slurries. The present study reveals that the mangrove sediment microbial structure is susceptible to PAH contamination,
and complex microbial community interactions occur in mangrove sediment. 相似文献
279.
Goldsteins G Keksa-Goldsteine V Ahtoniemi T Jaronen M Arens E Akerman K Chan PH Koistinaho J 《The Journal of biological chemistry》2008,283(13):8446-8452
This work demonstrates how increased activity of copper-zinc superoxide dismutase (SOD1) paradoxically boosts production of toxic reactive oxygen species (ROS) in the intermembrane space (IMS) of mitochondria. Even though SOD1 is a cytosolic enzyme, a fraction of it is found in the IMS, where it is thought to provide protection against oxidative damage. We found that SOD1 controls cytochrome c-catalyzed peroxidation in vitro when superoxide is available. The presence of SOD1 significantly increased the rate of ROS production in mitoplasts, which are devoid of outer membrane and IMS. In response to inhibition of respiration with antimycin A, isolated mouse wild-type mitochondria increased ROS production, but the mitochondria from mice lacking SOD1 (SOD1(-/-)) did not. Also, lymphocytes isolated from SOD1(-/-) mice produced significantly less ROS than did wild-type cells and were more resistant to apoptosis induced by inhibition of respiration. Moreover, an increased amount of the toxic mutant G93A SOD1 in the IMS increased ROS production. The mitochondrial dysfunction and cell damage paradoxically induced by SOD1-mediated ROS production may be implicated in chronic degenerative diseases. 相似文献
280.
Valentina Folgiero Paolo Avetrani Giulia Bon Selene E. Di Carlo Alessandra Fabi Cecilia Nisticò Patrizia Vici Elisa Melucci Simonetta Buglioni Letizia Perracchio Isabella Sperduti Laura Rosanò Ada Sacchi Marcella Mottolese Rita Falcioni 《PloS one》2008,3(2)