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991.
Cellular and Molecular Neurobiology - Histone deacetylases (HDACs) have been described to have both neurotoxic and neuroprotective roles, and partly, depend on its sub-cellular distribution. HDAC...  相似文献   
992.
The ongoing development of the Global Carbon Project (GCP) global methane (CH4) budget shows a continuation of increasing CH4 emissions and CH4 accumulation in the atmosphere during 2000–2017. Here, we decompose the global budget into 19 regions (18 land and 1 oceanic) and five key source sectors to spatially attribute the observed global trends. A comparison of top-down (TD) (atmospheric and transport model-based) and bottom-up (BU) (inventory- and process model-based) CH4 emission estimates demonstrates robust temporal trends with CH4 emissions increasing in 16 of the 19 regions. Five regions—China, Southeast Asia, USA, South Asia, and Brazil—account for >40% of the global total emissions (their anthropogenic and natural sources together totaling >270 Tg CH4 yr?1 in 2008–2017). Two of these regions, China and South Asia, emit predominantly anthropogenic emissions (>75%) and together emit more than 25% of global anthropogenic emissions. China and the Middle East show the largest increases in total emission rates over the 2000 to 2017 period with regional emissions increasing by >20%. In contrast, Europe and Korea and Japan show a steady decline in CH4 emission rates, with total emissions decreasing by ~10% between 2000 and 2017. Coal mining, waste (predominantly solid waste disposal) and livestock (especially enteric fermentation) are dominant drivers of observed emissions increases while declines appear driven by a combination of waste and fossil emission reductions. As such, together these sectors present the greatest risks of further increasing the atmospheric CH4 burden and the greatest opportunities for greenhouse gas abatement.  相似文献   
993.
In Vitro Cellular & Developmental Biology - Plant - Dioscorea deltoidea Wall. ex Griseb. is a critically endangered, commercially important crop of high medicinal value. Several accessions of...  相似文献   
994.
995.
OASS is a specific enzyme that helps Leishmania parasite to survive the oxidative stress condition in human macrophages. SAT C-terminal peptides in several organisms, including Leishmania, were reported to inhibit or reduce the activity of OASS. Small peptide and small molecules mimicking the SAT C-terminal residues are designed and tested for the inhibition of OASS in different organisms. Hence, in this study, all the possible tetra-peptide combinations were designed and screened based on the docking ability with Leishmania donovani OASS (Ld-OASS). The top ranked peptides were further validated for the stability using 50 ns molecular dynamic simulation. In order to identify the better binding capability of the peptides, the top peptides complexed with Ld-OASS were also subjected to molecular dynamic simulation. The docking and simulation results favored the peptide EWSI to possess greater advantage than previously reported peptide (DWSI) in binding with Ld-OASS active site. Also, screening of non-peptide inhibitor of Asinex Biodesign library based on the shape similarity of EWSI and DWSI was performed. The top similar molecules of each peptides were docked on to Ld-OASS active site and subsequently simulated for 20 ns. The results suggested that the ligand that shares high shape similarity with EWSI possess better binding capability than the ligand that shares high shape similarity with DWSI. This study revealed that the tetra-peptide EWSI had marginal advantage over DWSI in binding with Ld-OASS, thereby providing basis for defining a pharmacophoric scaffold for the design of peptidomimetic inhibitors as well as non-peptide inhibitors of Ld-OASS.

Communicated by Ramaswamy H. Sarma  相似文献   

996.
International Journal of Peptide Research and Therapeutics - Antimicrobial peptides are one of the important components of innate immune defense system and play a critical role in controlling...  相似文献   
997.
The effects of two different prey species on the pre-imaginal development and survival of the green lacewing, Chrysopa pallens were determined under laboratory conditions. The developmental duration from first instar to adult emergence was shorter when larvae were fed on Acyrthosiphon pisum (22.56 ± 0.39 d) than on Frankliniella occidentalis (29 ± 0.45 d). The survival rate of lacewings from first instar to adult emergence was 22.6% higher when they were fed on A. pisum than when fed on F. occidentalis. The possible implications of these findings are applicable to mass-rearing of C. pallens and for understanding predator's biology and survival capacity in the presence of prey species evaluated and could be used in the development of an effective biological control program.  相似文献   
998.
Propolis is a natural substance collected by honey bees from various plants such as, poplar, palm, pine, conifer secretions, gums, resins, mucilage and leaf buds. It is collected and brought very painstakingly by honey bees to be used for sealing cracks and crevices occurring in their hives. Originally, it as an antiseptic meant for preventing bee-hive from microbial infections along with preventing decomposition of intruders. Additionally, propolis has been used in folk medicine for centuries. The biological characteristics of propolis depend upon its chemical composition, plant sources, geographical zone and seasons. More than 300 compounds have been identified in propolis such as, phenolic compounds, aromatic acids, essential oils, waxes and amino acids. Many scientific articles are published every year in different international journals, and several groups of researchers have focused their attention on the chemical compounds and biological activity of propolis.  相似文献   
999.
Systemic lupus erythematosus(SLE) is a complex autoimmune syndrome characterized by various co-existing autoantibodies(auto Abs) in patients' blood.However,the full spectrum of auto Abs in SLE has not been comprehensively elucidated.In this study,a commercial platform bearing 9400 antigens(Proto Array) was used to identify auto Abs that were significantly elevated in the sera of SLE patients.By comparing the auto Ab profiles of SLE patients with those of healthy controls,we identified 437 Ig G and 1213 Ig M auto Abs that the expression levels were significantly increased in SLE(P 0.05).Use of the Proto Array platform uncovered over 300 novel auto Abs targeting a broad range of nuclear,cytoplasmic,and membrane antigens.Molecular interaction network analysis revealed that the antigens targeted by the auto Abs were most significantly enriched in cell death,cell cycle,and DNA repair pathways.A group of auto Abs associated with cell apoptosis and DNA repair function,including those targeting APEX1,AURKA,POLB,AGO1,HMGB1,IFIT5,MAPKAPK3,PADI4,RGS3,SRP19,UBE2 S,and VRK1,were further validated by ELISA and Western blot in a larger cohort.In addition,the levels of auto Abs against APEX1,HMGB1,VRK1,AURKA,PADI4,and SRP19 were positively correlated with the level of anti-ds DNA in SLE patients.Comprehensive auto Ab screening has identified novel auto Abs,which may shed light on potential pathogenic pathways leading to lupus.  相似文献   
1000.
Mitochondrion plays a significant role in a variety of biological functions. Because of their diverse character and location in the cellular systems, mitochondria commonly get exposed to various extrinsic and intrinsic cellular stresses. The present study reports a novel approach to detection of mitochondrial dysfunction based on tryptophan autofluorescence of its proteins in mouse liver, using laser‐induced fluorescence (LIF) as a tool. Mitochondria, isolated from the mouse liver, were initially tested for purity and integrity using lactate dehydrogenase and succinate dehydrogenase (SDH) assays. Mitochondrial stress was induced by treating the isolated mitochondria with heavy metals at 10 and 0.01 mM for sodium arsenite and mercuric chloride, respectively. Upon treatment with the heavy metal, tryptophan autofluorescence quenching was recorded at 281 nm excitation. The functional integrity of the mitochondria treated with heavy metals was evaluated by measuring SDH and cytochrome c oxidase activities at various concentrations of mitochondria, which showed impaired activity as compared to control upto a concentration of 6.25 μg. A significant shift was also observed in the autofluorescence of proteins upto the level below 1 μg, suggesting their conformational change and hence altered structural integrity of mitochondria. Circular dichroism spectroscopy data of the mitochondrial proteins treated with heavy metals further validates their conformational change as compared to untreated control. The present study clearly shows that the LIF can be a novel detection tool to detect altered structural integrity of cellular mitochondria upon stress, and it also possesses the potentiality to combine with other interdisciplinary modalities.  相似文献   
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