QTL Analysis of Some Agronomic Traits in Rice Under Different Growing Environments

The culm length, panicle length, spikelets per panicle and panicle exsertion were evaluated by using F2：3 population including 200 lines derived from the cross of indica and japonica Milyang 23/Jileng 1 under five different environments of Beijing （natural normal growing environment）, Kunming （natural cold environment）, Gongzhuling of China （cold water irrigation） and Chuncheon of Korea （natural normal growing environment and cold water irrigation）, and QTLs of these traits were analyzed by using SSR markers. The results showed that 44 QTLs related to these agronomic traits were detected under five different growing environments, and these QTLs have been located on 11 chromosomes except chromosome 9. The QTLs for qCLla, qCL1b, qCL5a, qCL6b, qPLla, qPL3a, qPL6b, qPL6c, qPL7b, qSP8b, qSPlc, qSP11a, qSP12, and qPE1 have been detected under more than two growing environments, and those that were little affected by environments, were stable QTLs. Among them, qCLla, qCLlb, qPLla, qSPlc, and qPE1 explained 24.2-55.2%, 22.7-39.9%, 12.5-27.7%, 14.4-33.5%, and 26.6-28.7% of observed phynotypic variation, respectively, which were major genes mainly appearing as overdominance. These QTLs cause the increase in action to culm length, panicle length, spikelets per panicle, and panicle exsertion under cold environment, showing that these QTLs were correlated with cold tolerance.     

Neurons containing NADPH-diaphorase are selectively resistant to quinolinate toxicity

Exposure of cultures of cortical cells from mouse to either of the endogenous excitatory neurotoxins quinolinate or glutamate resulted in widespread neuronal destruction; but only in the cultures exposed to quinolinate, an N-methyl-D-aspartate agonist, was there a striking preservation of the subpopulation of neurons containing the enzyme nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d). Further investigation revealed that neurons containing NADPH-d were also resistant to the toxicity of N-methyl-D-aspartate itself but were selectively vulnerable to the toxicity of either kainate or quisqualate. Thus, neurons containing NADPH-d may have an unusual distribution of receptors for excitatory amino acids, with a relative lack of N-methyl-D-aspartate receptors and a relative preponderance of kainate or quisqualate receptors. Since selective sparing of neurons containing NADPH-d is a hallmark of Huntington's disease, the results support the hypothesis that the disease may be caused by excess exposure to quinolinate or some other endogenous N-methyl-D-aspartate agonist.     

Estrogen modulates Bcl-2 family proteins in ischemic brain injury

Estradiol acts as a neuroprotective factor against brain injury. This study investigated whether estradiol modulates the Bcl-2 family proteins in ischemic brain injury. Adult female rats were ovariectomized and treated with estradiol prior to middle cerebral artery occlusion (MCAO). Brains were collected 24 hr after MCAO, and infarct volumes were analyzed. Estradiol significantly reduces the infarct volume and decreases the positive cells of TUNEL staining in cerebral cortex. In ischemic cerebral cortex, the level of Bcl-2 was decreased, and the level of Bax was significantly increased. Estradiol prevents the injury-induced decrease of Bcl-2 and increase of Bax. In conclusion, our findings suggest that estradiol plays a potent protective role in brain injury through the regulation of Bcl-2 family proteins.     

Chlorogenic acid alleviates the reduction of Akt and Bad phosphorylation and of phospho-Bad and 14-3-3 binding in an animal model of stroke

BackgroundStroke is caused by disruption of blood supply and results in permanent disabilities as well as death. Chlorogenic acid is a phenolic compound found in various fruits and coffee and exerts antioxidant, anti-inflammatory, and anti-apoptotic effects.ObjectivesThe purpose of this study was to investigate whether chlorogenic acid regulates the PI3K-Akt-Bad signaling pathway in middle cerebral artery occlusion (MCAO)-induced damage.MethodsChlorogenic acid (30 mg/kg) or vehicle was administered peritoneally to adult male rats 2 h after MCAO surgery, and animals were sacrificed 24 h after MCAO surgery. Neurobehavioral tests were performed, and brain tissues were isolated. The cerebral cortex was collected for Western blot and immunoprecipitation analyses.ResultsMCAO damage caused severe neurobehavioral disorders and chlorogenic acid improved the neurological disorders. Chlorogenic acid alleviated the MCAO-induced histopathological changes and decreased the number of terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells. Furthermore, MCAO-induced damage reduced the expression of phospho-PDK1, phospho-Akt, and phospho-Bad, which was alleviated with administration of chlorogenic acid. The interaction between phospho-Bad and 14-3-3 levels was reduced in MCAO animals, which was attenuated by chlorogenic acid treatment. In addition, chlorogenic acid alleviated the increase of cytochrome c and caspase-3 expression caused by MCAO damage.ConclusionsThe results of the present study showed that chlorogenic acid activates phospho-Akt and phospho-Bad and promotes the interaction between phospho-Bad and 14-3-3 during MCAO damage. In conclusion, chlorogenic acid exerts neuroprotective effects by activating the Akt-Bad signaling pathway and maintaining the interaction between phospho-Bad and 14-3-3 in ischemic stroke model.     

Histochemical study on neurodegeneration in the olfactory bulb after transient forebrain ischaemia in the Mongolian gerbil

In the present study, we investigated the ischaemia-related neurodegeneration in the main and accessory olfactory bulb (AOB) after 5 min transient forebrain ischaemia in the Mongolian gerbil using the acid fuchsin staining method. Between 5 and 15 days after ischaemia, acid fuchsin positive cells markedly increased in the external plexiform layer (EPL), mitral cell layer (ML) and glomerular layer (GL) of the main olfactory bulb (MOB), and in the mixed cell layer (MCL) and GL of the AOB. By 30 days after ischaemia reperfusion, acid fuchsin positive neurons were shrunken and showed low acidophilia in somata. Many necrotic vacuoles were found in the EPL and GL of the MOB 30 days after ischaemia. At this time, necrotic vacuoles were very few in the AOB. Therefore, our results suggest that the GL and EPL of the MOB are vulnerable to ischaemic damage at a later time after ischaemic insult, and that the AOB is more resistant to ischaemic damage as compared with the MOB.     

Nonproteolytic neuroprotection by human recombinant tissue plasminogen activator

Human recombinant tissue plasminogen activator (tPA) may benefit ischemic stroke patients by dissolving clots. However, independent of thrombolysis, tPA may also have deleterious effects on neurons by promoting excitotoxicity. Zinc neurotoxicity has been shown to be an additional key mechanism in brain injuries. Hence, if tPA affects zinc neurotoxicity, this may provide additional insights into its effect on neuronal death. Independent of its proteolytic action, tPA markedly attenuated zinc-induced cell death in cortical culture, and, when injected into cerebrospinal fluid, also reduced kainate seizure-induced hippocampal neuronal death in adult rats.     

Fortification of sulfited tannin from the bark of Acacia mangium with phenol–formaldehyde for use as plywood adhesive

The Acacia mangium tree contains 10% bark (v/v), of which about 20% are extractives. Extraction of this bark using a combination of water and sulfite medium can produce between 15% and 25% tannin materials (dry weight). In this work, several extraction conditions such as bark size, plantation site, extraction time and extraction medium were studied. The results showed that by using either hot water or a sulfite medium, a reasonable amount of tannin yield can be obtained. Bark size of less than 1-mm mesh size gave relatively high tannin yield irrespectively of the extraction medium used. Using a 600:100:2:0.5 (w/w) ratio of water:bark:sodium sulfite:sodium carbonate, and reacted at 75 °C for 3 h improved the tannin yield by at least 30%. The extracts were reasonably reactive towards formaldehyde as shown by their high Stiasny number; water extract, 60–70% and aqueous sulfite–carbonate extracts, 85–90%. The gluing results showed that the shear strength of the plywood can meet the requirements of the European Standards EN 314-1 and EN 314-2:1993. Incorporation of low molecular weight PF resin (10 parts) and PF (10 parts) improved the shear strength from 0.96 MPa to 1.43 MPa after a 72 h boiling test. This study showed that A. mangium tannin blended with commercial plywood phenol–formaldehyde resin, low molecular weight PF and paraformaldehyde as a cross-linker can be used to bond Kedondong (Canarium spp.) wood veneers suitable for both interior and exterior grade plywood.     

Dye-resist properties of reactive dye-resist agents in acid dyeing of silk

The dye-resist effect of reactive dye-resist agents in acid dyeing of silk was investigated. The dye-resist agent containing dichlorotriazine achieved a higher resist effectiveness than others since they make a charge barrier against diffusion in the silk fiber periphery due to the high reactivity of dichlorotriazine group. Especially, the increase in the number of ionic groups in acid dyes leads to better electrostatic repulsion of reactive dye resist agent treated silk and thus improves the resist effectiveness. However, the hydrophobicity effect of acid dyes on the dye-resist properties was relatively minor.     

Seeing the forest for the deer: Do reductions in deer-disturbance lead to forest recovery?

High levels of deer browsing can prevent canopy tree regeneration, but little is known about changes to forest size-structure following long-term deer herd reductions. We monitored changes in forest stand structure and composition in southwestern Ontario, Canada, over 28-years using permanent plots. Our study site was the largest remaining tract of Carolinian (deciduous) forest in Canada (11 km²), a habitat type that contains up to a fifth of Canada’s species at risk and is under intense anthropogenic pressures. We recorded declines in all tree size classes between 1981 and 1996, during which densities of white-tailed deer (Odocoileus virginianus) reached a peak of 55 deer km⁻². Despite significant and sustained deer herd reductions between 1996 and 2009, which reduced deer densities to 7 deer km⁻², there was limited recruitment of small trees and declines in basal area of tree species that were sensitive to deer browsing. Our results suggest that recovery from herbivory is a protracted process during which canopy tree regeneration may continue to decline despite a reduction in browsing pressure due to deer culling. Large declines in canopy-tree densities in Carolinian forests may lead to forest size-structures and herbaceous plant communities that resemble rare oak savanna habitat, creating difficult decisions for conservation managers aiming to protect rare and endangered species within native ecosystems. We recommend that managers protect Carolinian forest stands and encourage canopy tree regeneration by increasing seed sources of native trees. While deer control is essential in reducing forest damage, our results highlight the need to explore other forms of active management to expedite otherwise slow increases in tree density.