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Metal ionophores are considered as potential anti-dementia agents, and some are currently undergoing clinical trials. Many metals are known to accumulate and distribute abnormally in the aging brain. Alterations in zinc metal homeostasis in the glutaminergic synapse could contribute to ageing and the pathophysiology of Alzheimer’s disease (AD). The present study was designed to investigate the effect of metal ionophores on long term administration of zinc in D-galactose induced senescent mice. The ageing model was established by combined administration of zinc and D-galactose to mice for 6 weeks. A novel metal ionophore, PBT-2 was given daily to zinc-induced d-galactose senescent mice. The cognitive behaviour of mice was monitored using the Morris Water Maze. The anti-oxidant status and amyloidogenic activity in the ageing mouse was measured by determining mito-oxidative parameters and deposition of amyloid β (Aβ) in the brain. Systemic administration of both zinc and D-galactose significantly produced memory deficits, mito-oxidative damage, heightened acetylcholinesterase enzymatic activity and deposition of amyloid-β. Treatment with PBT-2 significantly improved behavioural deficits, biochemical profiles, cellular damage, and curbed the deposition of APP in zinc-induced senescent mice. These findings suggest that PBT-2, acting as a metal protein attenuating compound, may be helpful in the prevention of AD or alleviation of ageing.  相似文献   
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Even though significant breakthroughs with over 18% power conversion efficiencies (PCEs) in polymer:non‐fullerene acceptor (NFA) bulk heterojunction organic solar cells (OSCs) have been achieved, not many studies have focused on acquiring a comprehensive understanding of the underlying mechanisms governing these systems. This is because it can be challenging to delineate device photophysics in polymer:NFA blends comprehensively, and even more complicated to trace the origins of the differences in device photophysics to the subtle differences in energetics and morphology. Here, a systematic study of a series of polymer:NFA blends is conducted to unify and correlate the cumulative effects of i) voltage losses, ii) charge generation efficiencies, iii) non‐geminate recombination and extraction dynamics, and iv) nuanced morphological differences with device performances. Most importantly, a deconvolution of the major loss processes in polymer:NFA blends and their connections to the complex BHJ morphology and energetics are established. An extension to advanced morphological techniques, such as solid‐state NMR (for atomic level insights on the local ordering and donor:acceptor π? π interactions) and resonant soft X‐ray scattering (for donor and acceptor interfacial area and domain spacings), provide detailed insights on how efficient charge generation, transport, and extraction processes can outweigh increased voltage losses to yield high PCEs.  相似文献   
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Potato late blight, caused by the oomycete pathogen Phytophthora infestans, significantly hampers potato production. Recently, a new Resistance to Phytophthora infestans (Rpi) gene, Rpi-amr1, was cloned from a wild Solanum species, Solanum americanum. Identification of the corresponding recognized effector (Avirulence or Avr) genes from P. infestans is key to elucidating their naturally occurring sequence variation, which in turn informs the potential durability of the cognate late blight resistance. To identify the P. infestans effector recognized by Rpi-amr1, we screened available RXLR effector libraries and used long read and cDNA pathogen-enrichment sequencing (PenSeq) on four P. infestans isolates to explore the untested effectors. Using single-molecule real-time sequencing (SMRT) and cDNA PenSeq, we identified 47 highly expressed effectors from P. infestans, including PITG_07569, which triggers a highly specific cell death response when transiently coexpressed with Rpi-amr1 in Nicotiana benthamiana, suggesting that PITG_07569 is Avramr1. Here we demonstrate that long read and cDNA PenSeq enables the identification of full-length RXLR effector families and their expression profile. This study has revealed key insights into the evolution and polymorphism of a complex RXLR effector family that is associated with the recognition by Rpi-amr1.  相似文献   
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Journal of Plant Biochemistry and Biotechnology - Pigeonpea, an important legume crop is a good host plant for lac cultivation in North East India. In the present study, sixty-three polymorphic EST...  相似文献   
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Reed canary grass (RCG, Phalaris arundinacea L.) is a suitable energy crop for cultivation in northern peatlands. However, the atmospheric impact of RCG cultivation as influenced by harvest frequency and fertilization is not clear. Here, we compared the biomass yield and greenhouse gas (GHG) balance for RCG cultivation in peatlands affected by cutting frequency and fertilizer managements. The managements included one-cut (OC) and two-cut (TC) systems that were either fertilized (TC-F) or unfertilized (TC-U) after the first cut in summer. Biomass yield of OC, TC-F and TC-U were 12, 16 and 11 Mg dry biomass per hectare per year, respectively. GHG fluxes of CO2, N2O and CH4 were measured with closed chamber techniques in the period between first and second (final) harvest of the TC managements, i.e. from 15 June to 23 September 2011. In the GHG monitoring period of 100 days, all systems were net sources of CO2 corresponding to 64?±?3, 217?±?15 and 50?±?23 g?CO2-C?m?2 (mean?±?standard error, n?=?3) from the OC, TC-F and TC-U systems, respectively. In the same period, emissions of N2O from TC-F were ten times higher as compared to OC and TC-U. Emissions of CH4 were negligible from all systems. The TC systems could not improve the GHG balance during cultivation (271, 663 and 210 g CO2e-C?m?2 emissions from the OC, TC-F and TC-U systems, respectively), but in a broader GHG life cycle perspective, the increased biomass yield by TC-F could replace more fossil fuel and offset at least some of the higher emissions from the system.  相似文献   
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Over the past decades the role of nitric oxide (NO) and reactive oxygen species (ROS) in signaling and cellular responses to stress has witnessed an exponential trend line. Despite advances in the subject, our knowledge of the role of NO and ROS as regulators of stress and plant growth and their implication in signaling pathways is still partial. The crosstalk between NO and ROS during root formation offers new domains to be explored, as it regulates several plant functions. Previous findings indicate that plants utilize these signaling molecules for regulating physiological responses and development. Depending upon cellular concentration, NO either can stimulate or impede root system architecture (RSA) by modulating enzymes through post-translational modifications. Similarly, the ROS signaling molecule network, in association with other hormonal signaling pathways, control the RSA. The spatial regulation of ROS controls cell growth and ROS determine primary root and act in concert with NO to promote lateral root primordia. NO and ROS are two central messenger molecules which act differentially to upregulate or downregulate the expression of genes pertaining to auxin synthesis and to the configuration of root architecture. The investigation concerning the contribution of donors and inhibitors of NO and ROS can further aid in deciphering their role in root development. With this background, this review provides comprehensive details about the effect and function of NO and ROS in the development of RSA.  相似文献   
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Candida albicans and Aspergillus fumigatus are dangerous fungal pathogens with high morbidity and mortality, particularly in immunocompromised patients. Innate immune-mediated programmed cell death (pyroptosis, apoptosis, necroptosis) is an integral part of host defense against pathogens. Inflammasomes, which are canonically formed upstream of pyroptosis, have been characterized as key mediators of fungal sensing and drivers of proinflammatory responses. However, the specific cell death pathways and key upstream sensors activated in the context of Candida and Aspergillus infections are unknown. Here, we report that C. albicans and A. fumigatus infection induced inflammatory programmed cell death in the form of pyroptosis, apoptosis, and necroptosis (PANoptosis). Further, we identified the innate immune sensor Z-DNA binding protein 1 (ZBP1) as the apical sensor of fungal infection responsible for activating the inflammasome/pyroptosis, apoptosis, and necroptosis. The Zα2 domain of ZBP1 was required to promote this inflammasome activation and PANoptosis. Overall, our results demonstrate that C. albicans and A. fumigatus induce PANoptosis and that ZBP1 plays a vital role in inflammasome activation and PANoptosis in response to fungal pathogens.  相似文献   
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