336 research outputs found
Cerebrovascular expression of proteins related to inflammation, oxidative stress and neurotoxicity is altered with aging
<p>Abstract</p> <p>Background</p> <p>Most neurodegenerative diseases are age-related disorders; however, how aging predisposes the brain to disease has not been adequately addressed. The objective of this study is to determine whether expression of proteins in the cerebromicrovasculature related to inflammation, oxidative stress and neurotoxicity is altered with aging.</p> <p>Methods</p> <p>Brain microvessels are isolated from Fischer 344 rats at 6, 12, 18 and 24 months of age. Levels of interleukin (IL)-1β and IL-6 RNA are determined by RT-PCR and release of cytokines into the media by ELISA. Vessel conditioned media are also screened by ELISA for IL-1α, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α, (TNFα), and interferon γ (IFNγ). Immunofluorescent analysis of brain sections for IL-1β and IL-6 is performed.</p> <p>Results</p> <p>Expression of IL-1β and IL-6, both at RNA and protein levels, significantly (p < 0.01) decreases with age. Levels of MCP-1, TNFα, IL-1α, and IFNγ are significantly (p < 0.05-0.01) lower in 24 month old rats compared to 6 month old animals. Immunofluorescent analysis of brain vessels also shows a decline in IL-1β and IL-6 in aged rats. An increase in oxidative stress, assessed by increased carbonyl formation, as well as a decrease in the antioxidant protein manganese superoxide dismutase (MnSOD) is evident in vessels of aged animals. Finally, addition of microvessel conditioned media from aged rats to neuronal cultures evokes significant (p < 0.001) neurotoxicity.</p> <p>Conclusions</p> <p>These data demonstrate that cerebrovascular expression of proteins related to inflammation, oxidative stress and neurotoxicity is altered with aging and suggest that the microvasculature may contribute to functional changes in the aging brain.</p
Cerebrovascular expression of proteins related to inflammation, oxidative stress and neurotoxicity is altered with aging
<p>Abstract</p> <p>Background</p> <p>Most neurodegenerative diseases are age-related disorders; however, how aging predisposes the brain to disease has not been adequately addressed. The objective of this study is to determine whether expression of proteins in the cerebromicrovasculature related to inflammation, oxidative stress and neurotoxicity is altered with aging.</p> <p>Methods</p> <p>Brain microvessels are isolated from Fischer 344 rats at 6, 12, 18 and 24 months of age. Levels of interleukin (IL)-1β and IL-6 RNA are determined by RT-PCR and release of cytokines into the media by ELISA. Vessel conditioned media are also screened by ELISA for IL-1α, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α, (TNFα), and interferon γ (IFNγ). Immunofluorescent analysis of brain sections for IL-1β and IL-6 is performed.</p> <p>Results</p> <p>Expression of IL-1β and IL-6, both at RNA and protein levels, significantly (p < 0.01) decreases with age. Levels of MCP-1, TNFα, IL-1α, and IFNγ are significantly (p < 0.05-0.01) lower in 24 month old rats compared to 6 month old animals. Immunofluorescent analysis of brain vessels also shows a decline in IL-1β and IL-6 in aged rats. An increase in oxidative stress, assessed by increased carbonyl formation, as well as a decrease in the antioxidant protein manganese superoxide dismutase (MnSOD) is evident in vessels of aged animals. Finally, addition of microvessel conditioned media from aged rats to neuronal cultures evokes significant (p < 0.001) neurotoxicity.</p> <p>Conclusions</p> <p>These data demonstrate that cerebrovascular expression of proteins related to inflammation, oxidative stress and neurotoxicity is altered with aging and suggest that the microvasculature may contribute to functional changes in the aging brain.</p
Radiometric dating of late Quaternary loess in the northern piedmont of South Tianshan Mountains: Implications for reliable dating
Reliable chronologies are prerequisites when interpreting proxy records in terrestrial archives of Quaternary climate and environmental change. Optically stimulated luminescence (OSL) dating and accelerator mass spectrometry radiocarbon dating (AMS C-14) are commonly used to date late Quaternary loess deposits in the Chinese Loess Plateau, but the range and reliability of the two methods in Central Asia are still debated. In this study, we investigate both fine-grained quartz OSL and AMS C-14 dating of a late Quaternary loess section located at the northern piedmont of the South Tianshan Mountains in Central Asia and discuss the reliability of the two radiometric dating methods. The results show that the OSL and AMS C-14 ages are generally consistent with the stratigraphic sequence when the ages are younger than 25cal ka BP, which means that both can be used to establish a reliable chronology in the Ili Basin. But beyond this age, the OSL dating method seems to be a more reliable approach. The results also supported previous dates based on medium-grained quartz OSL dating of the Ili loess in the southern piedmont of the North Tianshan Mountains. Radiocarbon ages older than 25cal ka BP should be treated with caution, and attention must be paid to the influence of pedoturbation on OSL signals in the Central Asian loess. Multiple dating approaches for mutual authentication and exploring new dating materials are suggested in further loess chronological research. These findings will be helpful in establishing a reliable timescale and in reconstructing high-resolution environmental change in Central Asia
Poly[(acetato-κ2 O,O′)aqua(μ4-1H-benzimidazole-5,6-dicarboxylato-κ6 N 3:O 5,O 5′:O 5,O 6:O 6′)cerium(III)]
In the title compound, [Ce(C9H4N2O4)(C2H3O2)(H2O)]n, the CeIII ion is coordinated by five O atoms and one N atom from four 1H-benzimidazole-5,6-dicarboxylato (L) ligands and by two O atoms from an acetate ligand and one aqua ligand, forming a slightly distorted tricapped trigonal–prismatic geometry. The L ligands are bridging, forming a layered polymer parallel to (010). In the crystal, O—H⋯O and N—H⋯O hydrogen bonds connect the polymer layers into a three-dimensional network
Photocatalysis and Photoelectrochemistry for Solar Fuels
The Sun generates enough energy to power the Earth. However, solar energy should be stored into chemical energy to be conveniently used due to its low energy density and discontinuous radiation. In the last several years, photocatalysis and photoelectrochemistry for solar fuels have reattracted more and more governments’ and people’s interest from all over the world and become a very hot topic. If we utilize the abundant solar energy to convert CO2 into hydrocarbon fuels especially, it would address the problems of global climate change and solar energy storage at the same time. Recently, different new materials and ideas have been proposed and steady scientific progress has been done. However, it is still a key challenge to explore visible-light responsive materials with high photocatalytic activities. The special issue contains eight papers, where 6 papers are related to visible-light activity and 2 papers are related to UV activity
A highly robust and optimized sequence-based approach for genetic polymorphism discovery and genotyping in large plant populations
KEY MESSAGE: This optimized approach provides both a computational tool and a library construction protocol, which can maximize the number of genomic sequence reads that uniformly cover a plant genome and minimize the number of sequence reads representing chloroplast DNA and rRNA genes. One can implement the developed computational tool to feasibly design their own RAD-seq experiment to achieve expected coverage of sequence variant markers for large plant populations using information of the genome sequence and ideally, though not necessarily, information of the sequence polymorphism distribution in the genome. ABSTRACT: Advent of the next generation sequencing techniques motivates recent interest in developing sequence-based identification and genotyping of genome-wide genetic variants in large populations, with RAD-seq being a typical example. Without taking proper account for the fact that chloroplast and rRNA genes may occupy up to 60 % of the resulting sequence reads, the current RAD-seq design could be very inefficient for plant and crop species. We presented here a generic computational tool to optimize RAD-seq design in any plant species and experimentally tested the optimized design by implementing it to screen for and genotype sequence variants in four plant populations of diploid and autotetraploid Arabidopsis and potato Solanum tuberosum. Sequence data from the optimized RAD-seq experiments shows that the undesirable chloroplast and rRNA contributed sequence reads can be controlled at 3–10 %. Additionally, the optimized RAD-seq method enables pre-design of the required uniformity and density in coverage of the high quality sequence polymorphic markers over the genome of interest and genotyping of large plant or crop populations at a competitive cost in comparison to other mainstream rivals in the literature. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00122-016-2736-9) contains supplementary material, which is available to authorized users
A flexible two-stage constrained multi-objective evolutionary algorithm based on autonomic regulation
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The core element in solving constrained multi-objective problems (CMOPs) with evolutionary algorithms is simultaneously balancing objective optimization and constraint satisfaction. Maintaining this balance becomes more challenging for existing algorithms when dealing with complex CMOPs, as various complex feasible regions often result in CMOPs with very different characteristics. To address this issue, we propose a more flexible two-stage evolutionary algorithm based on automatic regulation (ARCMO), which can effectively control evolutionary trends to adapt to complex CMOPs. Specifically, the first stage performs a fast global search and passes the population information to the second stage. The second stage consists of two dynamically complementary sub-processes: the exploration subprocess and the convergence subprocess. The ratio of these two subprocesses is dynamically adjusted based on information from the first stage, allowing ARCMO to adapt to CMOPs with different complexities. Experiments on several recently proposed benchmark suites and real-world application problems show that ARCMO is more adaptable than the contender algorithms when solving different complex CMOPs
Poly[(μ-1H-benzimidazole-5,6-dicarboxylato)lead(II)]
The crystal structure of the two-dimensional polymeric title compound, [Pb(C9H4N2O4)]n, comprises one crystallographically independent PbII atom and one fully deprotonated 1H-benzimidazole-5,6-dicarboxylate (H2
L) ligand. The PbII atom is seven-coordinated by six O atoms and one N atom from the H2
L ligands, giving a capped octahedral coordination geometry. The structure is a layered two-dimensional coordination polymer extending parallel to (100) with N—H⋯O hydrogen bonds interactions between the layers, stabilizing the crystal structure
Sculpting the maturation, softening and ethylene pathway: The influences of microRNAs on tomato fruits
<p>Abstract</p> <p>Background</p> <p>MicroRNAs (miRNAs), a ubiquitous class of short RNAs, play vital roles in physiological and biochemical processes in plants by mediating gene silencing at post-transcriptional (PTGS) level. Tomato is a model system to study molecular basis of fleshy fruit ripening and senescence, ethylene biosynthesis and signal transduction owing to its genetic and molecular tractability. To study the functions of miRNAs in tomato fruit ripening and senescence, and their possible roles in ethylene response, the next generation sequencing method was employed to identify miRNAs in tomato fruit. Bioinformatics and molecular biology approaches were combined to profile the miRNAs expression patterns at three different fruit ripening stages and by exogenous ethylene treatment.</p> <p>Results</p> <p>In addition to 7 novel miRNA families, 103 conserved miRNAs belonging to 24 families and 10 non-conserved miRNAs matching 9 families were identified in our libraries. The targets of many these miRNAs were predicted to be transcriptional factors. Other targets are known to play roles in the regulation of metabolic processes. Interestingly, some targets were predicted to be involved in fruit ripening and softening, such as Pectate Lyase, beta-galactosidase, while a few others were predicted to be involved in ethylene biosynthesis and signaling pathway, such as ACS, EIN2 and CTR1. The expression patterns of a number of such miRNAs at three ripening stages were confirmed by stem-loop RT-PCR, which showed a strong negative correlation with that of their targets. The regulation of exogenous ethylene on miRNAs expression profiles were analyzed simultaneously, and 3 down-regulated, 5 up-regulated miRNAs were found in this study.</p> <p>Conclusions</p> <p>A combination of high throughput sequencing and molecular biology approaches was used to explore the involvement of miRNAs during fruit ripening. Several miRNAs showed differential expression profiles during fruit ripening, and a number of miRNAs were influenced by ethylene treatment. The results suggest the importance of miRNAs in fruit ripening and ethylene response.</p
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