Cytokinin oxidase regulates rice grain production

Most agriculturally important traits are regulated by genes known as quantitative trait loci (QTLs) derived from natural allelic variations. We here show that a QTL that increases grain productivity in rice, Gn1a, is a gene for cytokinin oxidase/dehydrogenase (OsCKX2), an enzyme that degrades the phytohormone cytokinin. Reduced expression of OsCKX2 causes cytokinin accumulation in inflorescence meristems and increases the number of reproductive organs, resulting in enhanced grain yield. QTL pyramiding to combine loci for grain number and plant height in the same genetic background generated lines exhibiting both beneficial traits. These results provide a strategy for tailormade crop improvement.     

An oral vaccine against NMDAR1 with efficacy in experimental stroke and epilepsy

The brain is generally considered immunoprivileged, although increasing examples of immunological responses to brain antigens, neuronal expression of major histocompatibility class I genes, and neurological autoimmunity have been recognized. An adeno-associated virus (AAV) vaccine generated autoantibodies that targeted a specific brain protein, the NR1 subunit of the N-methyl-D-aspartate (NMDA) receptor. After peroral administration of the AAV vaccine, transgene expression persisted for at least 5 months and was associated with a robust humoral response in the absence of a significant cell-mediated response. This single-dose vaccine was associated with strong anti-epileptic and neuroprotective activity in rats for both a kainate-induced seizure model and also a middle cerebral artery occlusion stroke model at 1 to 5 months following vaccination. Thus, a vaccination strategy targeting brain proteins is feasible and may have therapeutic potential for neurological disorders.     

Kilimanjaro ice core records: evidence of holocene climate change in tropical Africa

Six ice cores from Kilimanjaro provide an approximately 11.7-thousand-year record of Holocene climate and environmental variability for eastern equatorial Africa, including three periods of abrupt climate change: approximately 8.3, approximately 5.2, and approximately 4 thousand years ago (ka). The latter is coincident with the "First Dark Age," the period of the greatest historically recorded drought in tropical Africa. Variable deposition of F- and Na+ during the African Humid Period suggests rapidly fluctuating lake levels between approximately 11.7 and 4 ka. Over the 20th century, the areal extent of Kilimanjaro's ice fields has decreased approximately 80%, and if current climatological conditions persist, the remaining ice fields are likely to disappear between 2015 and 2020.     

Imaging doped holes in a cuprate superconductor with high-resolution Compton scattering

The high-temperature superconducting cuprate La(2-x)Sr(x)CuO(4) (LSCO) shows several phases ranging from antiferromagnetic insulator to metal with increasing hole doping. To understand how the nature of the hole state evolves with doping, we have carried out high-resolution Compton scattering measurements at room temperature together with first-principles electronic structure computations on a series of LSCO single crystals in which the hole doping level varies from the underdoped (UD) to the overdoped (OD) regime. Holes in the UD system are found to primarily populate the O 2p(x)/p(y) orbitals. In contrast, the character of holes in the OD system is very different in that these holes mostly enter Cu d orbitals. High-resolution Compton scattering provides a bulk-sensitive method for imaging the orbital character of dopants in complex materials.     

Spin transition zone in Earth's lower mantle

Mineral properties in Earth's lower mantle are affected by iron electronic states, but representative pressures and temperatures have not yet been probed. Spin states of iron in lower-mantle ferropericlase have been measured up to 95 gigapascals and 2000 kelvin with x-ray emission in a laser-heated diamond cell. A gradual spin transition of iron occurs over a pressure-temperature range extending from about 1000 kilometers in depth and 1900 kelvin to 2200 kilometers and 2300 kelvin in the lower mantle. Because low-spin ferropericlase exhibits higher density and faster sound velocities relative to the high-spin ferropericlase, the observed increase in low-spin (Mg,Fe)O at mid-lower mantle conditions would manifest seismically as a lower-mantle spin transition zone characterized by a steeper-than-normal density gradient.     

Suppressive effect of the ethanolic extract of adlay bran on cytochrome P-450 enzymes in rat liver and lungs

Adlay ( Coix lachryma-jobi L. var. ma-yuen Stapf) is a grass crop and is reported to protect against various diseases such as cancer. To investigate the effect of the ethanolic extract of adlay bran (ABE) on drug-metabolizing enzymes and glutathione-related antioxidant enzymes in rats, three groups of eight male Sprague-Dawley rats each were fed a control diet or a diet containing 5 or 10% ABE for 4 weeks. Significant decreases in microsomal cytochrome P-450 (CYP) 1A1-catalyzed ethoxyresorufin O-deethylation, CYP2C-catalyzed diclofenac 4-hydroxylation, CYP2D-catalyzed dextromethorphan O-demethylation, and CYP3A-catalyzed testosterone 6β-hydroxylation in the liver and CYP1A1-catalyzed ethoxyresorufin O-deethylation in the lungs of rats fed ABE were observed. Immunoblot analyses also showed decreases of CYP1A1, 1A2, 2C6, 2C11, 2D1, 2E1, 3A1, and 3A2 in the liver and CYP1A1 in the lungs. Furthermore, rats fed the 10% ABE diet had a higher glutathione content and glutathione peroxidase, glutathione reductase, and glutathione S-transferase activities in the lungs, but such an increase was not noted in the liver. Inhibition of various CYP-catalyzed enzyme reactions by ABE in rat and human liver microsomes had also been shown. The results of this study indicate that ABE feeding may suppress CYP enzyme activities and CYP protein expression in the liver and lungs of rats. Moreover, the increase of the antioxidant potential by ABE is tissue-specific.     

Mechanochemical-assisted extraction and antioxidant activities of kaempferol glycosides from Camellia oleifera Abel. meal

A mechanochemical-assisted extraction (MCAE) method was proposed and investigated for the fast extraction of two kaempferol glycosides (kaempferol-3-O-[2-O-β-D-galactopyranosyl-6-O-α-L-rhamnopyranosyl]-β-D-glucopyranoside and kaempferol-3-O-[2-O-β-D-xylopyranosyl-6-O-α-L-rhamnopyranosyl]-β-D-glucopyranoside) from Camellia oleifera Abel. meal. The effects of operating parameters in terms of NaOH content, grinding time, extraction time, and ratio of solution to solid were evaluated by means of response surface methodology (RSM). Under the optimal conditions with a ratio of material to NaOH of 20:1 (g/g), a milling time of 15 min, and a ratio of solution to solid of 20:1 (mL/g) for 60 min, the maximum extraction yields of the two kaempferol glycosides reached 13.34 and 13.83%, respectively. The antioxidant activity of kaempferol glycosides extract was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay and ferric thiocyanate (FTC) assay. Compared with the heat reflux extraction (HRE) method, the yield and the antioxidant activities of the extracts from MCAE with water as solvent were higher and stronger.     

Identification of methanol-soluble compounds in sesame and evaluation of antioxidant potential of its lignans

The methanol extract of sesame (Sesamum indicum) seeds was fractionated and purified with the assistance of conventional column chromatography to afford 29 compounds including seven furofuran lignans. Among these isolates, (+)-samin (1) was obtained from the natural source for the first time. In addition, (-)-asarinin (30) and sesamol (31) were generated by oxidative derivation from (+)-sesamolin (2) and (+)-sesamin (3), two abundant lignans found in sesame seeds. To evaluate their in vitro antioxidant potential, the seven isolated lignans (1-7) and the two derivatives (30 and 31) were examined for the scavenging activities on DPPH free radicals and superoxide anions. Moreover, the capability of chelating ferrous ions and reducing power of these sesame lignans were also measured. The results suggest that, besides the well-known sesamolin and sesamin, the minor sesame lignans (+)-(7S,8'R,8R)-acuminatolide (5), (-)-piperitol (6), and (+)-pinoresinol (7) are also adequate active ingredients and may be potential sources for nutritional and pharmacological utilization.     

Antioxidative caffeoylquinic acids and flavonoids from Hemerocallis fulva flowers

Tumor necrosis factor-α (TNF-α)-induced reactive oxygen species (ROS) production in HepG2 was used to screen hepatocyte protective compounds from the flowers of Hemerocallis fulva. Three new polyphenols, n-butyl 4-trans-O-caffeoylquinate (1), kaempferol 3-O-{α-L-rhamnopyranosyl(1→6)[α-L-rhamnopyranosyl(1→2)]}-β-D-galactopyranoside (2), and chrysoeriol 7-O-[β-D-glucuronopyranosyl(1→2)(2-O-trans-feruloyl)-β-D-glucuronopyranoside (3), together with four caffeoylquinic acid derivatives (4-7), eight known flavones (8-15), one naphthalene glycoside, stelladerol (16), one tryptophan derivative (17), adenosine (18), and guanosine (19) were isolated from the bioactive fractions of the aqueous ethanol extract of H. fulva flowers. The structures of isolated compounds were characterized by means of spectroscopic data. Compounds 1-3 were described as first isolated natural products. Among the above-mentioned compounds, the caffeoylquinic acid derivatives are the major components with potent free radical scavenging activity in HepG2 cells and are for the first time isolated from H. fulva flowers. A convenient ultraperformance liquid chromatography (UPLC) method was also developed to simultaneously separate and identify caffeoylquinic acids and flavonoids promptly.     

Metabolite profiles for Antrodia cinnamomea fruiting bodies harvested at different culture ages and from different wood substrates

Antrodia cinnamomea is a precious edible fungus endemic to Taiwan that has long been used as a folk remedy for health promotion and for treating various diseases. In this study, an index of 13 representative metabolites from the ethanol extract of A. cinnamomea fruiting body was established for use in quality evaluation. Most of the index compounds selected, particularly the ergostane-type triterpenoids and polyacetylenes, possess good anti-inflammation activity. A comparison of the metabolite profiles of different ethanol extracts from A. cinnamomea strains showed silmilar metabolites when the strains were grown on the original host wood (Cinnamomum kanehirai) and harvested after the same culture time period (9 months). Furthermore, the amounts of typical ergostane-type triterpenoids in A. cinnamomea increased with culture age. Culture substrates also influenced metabolite synthesis; with the same culture age, A. cinnamomea grown on the original host wood produced a richer array of metabolites than A. cinnamomea cultured on other wood species. We conclude that analysis of a fixed group of compounds including triterpenoids, benzolics, and polyacetylenes constitutes a suitable, reliable system to evaluate the quality of ethanol extract from A. cinnamomea fruiting bodies. The evaluation system established in this study may provide a platform for analysis of the products of A. cinnamomea.