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991.
Verticillium dahliae represents one of the main limiting factors in olive production in the Mediterranean countries. Increasing shortage of fresh water and land, increase the pressure on using alternative sources of marginal or saline water, and land previously cropped with V. dahliae host plants. The objective of the present study was to evaluate the influence of salinity on V. dahliae expression in olive stem cuttings. V. dahliae‐inoculated cuttings of cvs. Picual, Frantoio, Mansanillo and Barnea, showed higher senescence symptoms than their non‐inoculated controls. Colonization levels obtained in cv. Picual were significantly higher than in cv. Frantoio. Manzanillo was the most sensitive cultivar to salinity alone, with significant senescence symptoms in 4 and 6 dS/m NaCl treatments. When cv. Manzanillo was exposed to both salinity and V. dahliae, significantly higher senescence symptoms were obtained as compared with each of them separately. Senescence symptoms of cv. Picual exposed to V. dahliae, whether or not in combination with saline solutions, were significantly higher than those when cuttings were exposed to a saline solution alone. In cv. Frantoio, which is more resistant to salinity than the other cultivars, significantly high senescence symptoms were observed only in combination of V. dahliae and high saline concentration (8 dS/m). The fungal colonization index in cv. Manzanillo in high salinity (8 dS/m) was significantly higher than in the treatment without salt. In cv. Barnea, colonization index in 8 dS/m salinity was significantly higher than in the 4 dS/m concentration or control (fresh water). In conclusion, our findings demonstrate the interaction between V. dahliae and saline irrigation in various cultivars. Thus, stem cuttings could serve as an effective screening method in breeding olive clones for V. dahliae resistance, salt tolerance and their interaction. 相似文献
992.
993.
Guy Levin Sharon Kulikovsky Varda Liveanu Benjamin Eichenbaum Ayala Meir Tal Isaacson Yaakov Tadmor Noam Adir Gadi Schuster 《The Plant journal : for cell and molecular biology》2021,106(5):1260-1277
Although light is the driving force of photosynthesis, excessive light can be harmful. One of the main processes that limits photosynthesis is photoinhibition, the process of light-induced photodamage. When the absorbed light exceeds the amount that is dissipated by photosynthetic electron flow and other processes, damaging radicals are formed that mostly inactivate photosystem II (PSII). Damaged PSII must be replaced by a newly repaired complex in order to preserve full photosynthetic activity. Chlorella ohadii is a green microalga, isolated from biological desert soil crusts, that thrives under extreme high light and is highly resistant to photoinhibition. Therefore, C. ohadii is an ideal model for studying the molecular mechanisms underlying protection against photoinhibition. Comparison of the thylakoids of C. ohadii cells that were grown under low light versus extreme high light intensities found that the alga employs all three known photoinhibition protection mechanisms: (i) massive reduction of the PSII antenna size; (ii) accumulation of protective carotenoids; and (iii) very rapid repair of photodamaged reaction center proteins. This work elucidated the molecular mechanisms of photoinhibition resistance in one of the most light-tolerant photosynthetic organisms, and shows how photoinhibition protection mechanisms evolved to marginal conditions, enabling photosynthesis-dependent life in severe habitats. 相似文献
994.
Chia-Jung Chang Ho-Chang Kuo Jeng-Sheng Chang Jong-Keuk Lee Fuu-Jen Tsai Chiea Chuen Khor Li-Ching Chang Shih-Ping Chen Tai-Ming Ko Yi-Min Liu Ying-Ju Chen Young Mi Hong Gi Young Jang Martin L. Hibberd Taco Kuijpers David Burgner Michael Levin Jane C. Burns Sonia Davila International Kawasaki Disease Genetics Consortium? Korean Kawasaki Disease Genetics Consortium? Taiwan Kawasaki Disease Genetics Consortium? Yuan-Tsong Chen Chien-Hsiun Chen Jer-Yuarn Wu Yi-Ching Lee 《PloS one》2013,8(8)
The BLK and CD40 loci have been associated with Kawasaki disease (KD) in two genome-wide association studies (GWAS) conducted in a Taiwanese population of Han Chinese ancestry (Taiwanese) and in Japanese cohorts. Here we build on these findings with replication studies of the BLK and CD40 loci in populations of Korean and European descent. The BLK region was significantly associated with KD susceptibility in both populations. Within the BLK gene the rs2736340-located linkage disequilibrium (LD ) comprising the promoter and first intron was strongly associated with KD, with the combined results of Asian studies including Taiwanese, Japanese, and Korean populations (2,539 KD patients and 7,021 controls) providing very compelling evidence of association (rs2736340, OR = 1.498, 1.354–1.657; P = 4.74×10−31). We determined the percentage of B cells present in the peripheral blood mononuclear cell (PBMC) population and the expression of BLK in the peripheral blood leukocytes (leukocytes) of KD patients during the acute and convalescent stages. The percentage of B cells in the PBMC population and the expression of BLK in leukocytes were induced in patients in the acute stage of KD. In B cell lines derived from KD patients, and in purified B cells from KD patients obtained during the acute stage, those with the risk allele of rs2736340 expressed significantly lower levels of BLK. These results suggest that peripheral B cells play a pathogenic role during the acute stage of KD. Decreased BLK expression in peripheral blood B cells may alter B cell function and predispose individuals to KD. These associative data suggest a role for B cells during acute KD. Understanding the functional implications may facilitate the development of B cell-mediated therapy for KD. 相似文献
995.
Myrsini Kaforou Victoria J. Wright Tolu Oni Neil French Suzanne T. Anderson Nonzwakazi Bangani Claire M. Banwell Andrew J. Brent Amelia C. Crampin Hazel M. Dockrell Brian Eley Robert S. Heyderman Martin L. Hibberd Florian Kern Paul R. Langford Ling Ling Marc Mendelson Tom H. Ottenhoff Femia Zgambo Robert J. Wilkinson Lachlan J. Coin Michael Levin 《PLoS medicine》2013,10(10)
996.
Christina Drevinge Lars O. Karlsson Marcus St?hlman Thomas Larsson Jeanna Perman Sundelin Lars Grip Linda Andersson Jan Borén Malin C. Levin 《PloS one》2013,8(4)
Myocardial ischemia is associated with intracellular accumulation of lipids and increased depots of myocardial lipids are linked to decreased heart function. Despite investigations in cell culture and animal models, there is little data available on where in the heart the lipids accumulate after myocardial ischemia and which lipid species that accumulate. The aim of this study was to investigate derangements of lipid metabolism that are associated with myocardial ischemia in a porcine model of ischemia and reperfusion. The large pig heart enables the separation of the infarct area with irreversible injury from the area at risk with reversible injury and the unaffected control area. The surviving myocardium bordering the infarct is exposed to mild ischemia and is stressed, but remains viable. We found that cholesteryl esters accumulated in the infarct area as well as in the bordering myocardium. In addition, we found that expression of the low density lipoprotein receptor (LDLr) and the low density lipoprotein receptor-related protein 1 (LRP1) was up-regulated, suggesting that choleteryl ester uptake is mediated via these receptors. Furthermore, we found increased ceramide accumulation, inflammation and endoplasmatic reticulum (ER) stress in the infarcted area of the pig heart. In addition, we found increased levels of inflammation and ER stress in the myocardium bordering the infarct area. Our results indicate that lipid accumulation in the heart is one of the metabolic derangements remaining after ischemia, even in the myocardium bordering the infarct area. Normalizing lipid levels in the myocardium after ischemia would likely improve myocardial function and should therefore be considered as a target for treatment. 相似文献
997.
998.
Agnes N. Kiragga Barbara Castelnuovo Rachel Musomba Jonathan Levin Andrew Kambugu Yukari C. Manabe Constantin T. Yiannoutsos Noah Kiwanuka 《PloS one》2013,8(12)
Background
In sub-Saharan Africa, a large proportion of HIV positive patients on antiretroviral therapy (ART) are lost to follow-up, some of whom are dead. The objective of this study was to validate methods used to correct mortality estimates for loss-to-follow-up using a cohort with complete death ascertainment.Methods
Routinely collected data from HIV patients initiating first line antiretroviral therapy (ART) at the Infectious Diseases Institute (IDI) (Routine Cohort) was used. Three methods to estimate mortality after initiation were: 1) standard Kaplan-Meier estimation (uncorrected method) that uses passively observed data; 2) double-sampling methods by Frangakis and Rubin (F&R) where deaths obtained from patient tracing studies are given a higher weight than those passively ascertained; 3) Nomogram proposed by Egger et al. Corrected mortality estimates in the Routine Cohort, were compared with the estimates from the IDI research observational cohort (Research Cohort), which was used as the “gold-standard”.Results
We included 5,633 patients from the Routine Cohort and 559 from the Research Cohort. Uncorrected mortality estimates (95% confidence interval [1]) in the Routine Cohort at 1, 2 and 3 years were 5.5% (4.9%–6.3%), 6.6% (5.9%–7.5%) and 7.4% (6.5%–8.5%), respectively. The F&R corrected estimates at 1, 2 and 3 years were 11.2% (5.8%–21.2%), 15.8% (9.9%–24.8%) and 18.5% (12.3% –27.2%) respectively. The estimates obtained from the Research Cohort were 15.6% (12.8%–18.9%), 17.5% (14.6%–21.0%) and 19.0% (15.3%–21.9%) at 1, 2 and 3 years respectively. Using the nomogram method in the Routine Cohort, the corrected programme-level mortality estimate in year 1 was 11.9% (8.0%–15.7%).Conclusion
Mortality adjustments provided by the F&R and nomogram methods are adequate and should be employed to correct mortality for loss-to-follow-up in large HIV care centres in Sub-Saharan Africa. 相似文献999.
David A. Bowden Ashley A. Rowden Andrew R. Thurber Amy R. Baco Lisa A. Levin Craig R. Smith 《PloS one》2013,8(10)
Cold seep communities with distinctive chemoautotrophic fauna occur where hydrocarbon-rich fluids escape from the seabed. We describe community composition, population densities, spatial extent, and within-region variability of epifaunal communities at methane-rich cold seep sites on the Hikurangi Margin, New Zealand. Using data from towed camera transects, we match observations to information about the probable life-history characteristics of the principal fauna to develop a hypothetical succession sequence for the Hikurangi seep communities, from the onset of fluid flux to senescence. New Zealand seep communities exhibit taxa characteristic of seeps in other regions, including predominance of large siboglinid tubeworms, vesicomyid clams, and bathymodiolin mussels. Some aspects appear to be novel; however, particularly the association of dense populations of ampharetid polychaetes with high-sulphide, high-methane flux, soft-sediment microhabitats. The common occurrence of these ampharetids suggests they play a role in conditioning sulphide-rich sediments at the sediment-water interface, thus facilitating settlement of clam and tubeworm taxa which dominate space during later successional stages. The seep sites are subject to disturbance from bottom trawling at present and potentially from gas hydrate extraction in future. The likely life-history characteristics of the dominant megafauna suggest that while ampharetids, clams, and mussels exploit ephemeral resources through rapid growth and reproduction, lamellibrachid tubeworm populations may persist potentially for centuries. The potential consequences of gas hydrate extraction cannot be fully assessed until extraction methods and target localities are defined but any long-term modification of fluid flow to seep sites would have consequences for all chemoautotrophic fauna. 相似文献
1000.