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111.
Koh PO Cho GJ Choi WS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1019-1022
Estradiol acts as a neuroprotective factor against ischemic brain injury. This study investigated whether estradiol modulates neuroprotective mechanism through the activation of Akt and its downstream target such as Bad in global ischemic injury. Adult female gerbils were ovariectomized and treated with estradiol prior to ischemic injury. Transient cerebral ischemia was accomplished by bilateral clipping of the common carotid artery for 5 min. Brains were collected on 1, 3, 5 day after injury. In hippocampal CA1 region of non-treated gerbils, most of neuronal cells exhibited pyknotic nuclei and showed the positive reaction of TUNEL staining on 5 day after injury. However, estradiol significantly reduced the neuronal cell death. Potential activation was measured by phosphorylation of Akt at Ser473 and Bad at Ser136 using western blot analysis. The levels of pAkt and pBad were significantly decreased in non-treated gerbils on 1-5 day after injury. However, estradiol prevents the global ischemic injury-induced decrease of pAkt and pBad. Our findings suggest that estradiol prevents cell death due to global ischemic injury and that Akt activation and Bad phosphorylation by estradiol mediated these protective effects. 相似文献
112.
Jens Wohlers In-Ock Koh Wolfram Thiemann Wolfgang Rotard 《Water, air, and soil pollution》2009,196(1-4):101-113
Pesticides presently being discharged into the aquatic environment are not only toxic but also only partially biodegradable, they are not easily removed by conventional water treatment plants. Air ionization devices using an atmospheric pressure corona discharge process show great promise in improving degradation of chemical and biological contaminants in water purification plants. In order to assess the effectiveness of this air ionization apparatus, laboratory scale degradation experiments were carried out systematically in a bubble column reactor containing a variety of pesticides such as triazines, carbamates, phenyl urea derivates and chlorophenols relative to the addition of humic acid and inorganic chemicals as well as to pH variation. Chemical oxygen demand (COD) decreased with air ionization treatment and the rate of the biological oxygen demand related to this (BOD/COD) showed improved pesticide biodegradability. Changes in water toxicity were monitored by Daphnia- and Luminescence Bacteria tests. This novel water treatment process is shown to be a potent oxidation technique for persistent organic pollutants such as pesticides. 相似文献
113.
Sung JH Kim MO Koh PO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(1):35-41
Nicotinamide attenuates neuronal cell death related to focal cerebral ischemic injury. This study investigated whether nicotinamide exerts a neuroprotective effect through the activation of Raf- mitogen-activated protein kinase kinase (MEK)-ERK and its downstream targets, including p90 ribosomal S6 kinase (p90RSK) and Bad. Adult male Sprague-Dawley rats were treated with nicotinamide (500 mg/kg) or vehicle 2 hr after the onset of middle cerebral artery occlusion (MCAO). Brains were collected 24 hr after MCAO. In the present study, nicotinamide significantly reduces the volume of infarct regions and decreases the number of positive cells by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining in the cerebral cortex. Nicotinamide prevents injury-induced decrease in Raf-1, MEK1/2, and ERK1/2 phosphorylation. As part of the downstream cascade, nicotinamide inhibits the injury-induced decrease in p90RSK and Bad phosphorylation. Moreover, nicotinamide prevents the injury-induced increase in cleaved caspase-3 levels. These findings suggest that nicotinamide protects neuronal cells against cerebral ischemic injury and that MEK-ERK-p90RSK cascade activation by nicotinamide contributes to these neuroprotective effects. 相似文献
114.
Navjot S. Sodhi Lian Pin Koh Dewi M. Prawiradilaga Idris Tinulele Tommy Han Tong Tan 《Biological conservation》2005,122(4):547-558
Unprecedented deforestation is currently underway in Southeast Asia. Since this trend is likely to continue, it is critical to determine the value of human-modified habitats (e.g., mixed-rural habitat) for conserving the regional native forest avifauna. The impacts of ongoing deforestation on the highly endemic avifauna (33%) of Sulawesi (Indonesia) are poorly understood. We sampled birds in primary and secondary forests in the Lore Lindu National Park in central Sulawesi, as well as the surrounding plantation and mixed-rural habitats. Species richness, species density and population density of forest birds showed a consistent decreasing trend in the following order: primary forests > secondary forests > mixed-rural habitat > plantations. Although primary forests contained the highest proportion (85%) of a total of 34 forest species recorded from our point count surveys, 40-yr old secondary forests and the mixed-rural habitat showed high conservation potential, containing 82% and 76% of the forest species, respectively. Plantations recorded only 32% of the forest bird species. Fifteen forest species had the highest abundance in primary forests, while two species had higher abundance outside primary forests. Our simulations revealed that all forest birds that were sensitive to native tree cover could be found in areas with at least 20% continuous native tree cover. Our study shows that although primary forests have the highest conservation value for forest avifauna, the potential of degraded habitats, such as secondary forests and the mixed-rural habitat, for conserving forest species can be enhanced with appropriate land use and management decisions. 相似文献
115.
Sleep is an essential process conserved from flies to humans. The importance of sleep is underscored by its tight homeostatic control. Through a forward genetic screen, we identified a gene, sleepless, required for sleep in Drosophila. The sleepless gene encodes a brain-enriched, glycosylphosphatidylinositol-anchored protein. Loss of SLEEPLESS protein caused an extreme (>80%) reduction in sleep; a moderate reduction in SLEEPLESS had minimal effects on baseline sleep but markedly reduced the amount of recovery sleep after sleep deprivation. Genetic and molecular analyses revealed that quiver, a mutation that impairs Shaker-dependent potassium current, is an allele of sleepless. Consistent with this finding, Shaker protein levels were reduced in sleepless mutants. We propose that SLEEPLESS is a signaling molecule that connects sleep drive to lowered membrane excitability. 相似文献
116.
HAN Long-zhi QIAO Yong-li ZHANG San-yuan CAO Gui-lan YE Chang-rong XU Fu-rong DAI Lu-yuan YeJong-doo Koh Hee-jong 《中国农业科学(英文版)》2006,5(1):15-22
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. 相似文献
117.
The ability of institutionalized retardates in scaling musical preferences was compared with that of normals. The retardates' scale values and scale forms obtained by two kinds of scaling procedures are very similar to those of normals. Deficits, however, are observed in their lower internal consistency and relative uncertainty and in higher response polarization and perseveration. 相似文献
118.
Neurons containing NADPH-diaphorase are selectively resistant to quinolinate toxicity 总被引:14,自引:0,他引:14
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. 相似文献
119.
Joni Kujansuu Koh Yasue Takayoshi Koike Anatoly P. Abaimov Takuya Kajimoto Takashi Takeda Morihiko Tokumoto Yojiro Matsuura 《Journal of Wood Science》2007,53(2):87-93
An analysis was performed on the climatic responses of the radial growth of Larix gmelinii (Rupr.) Rupr. on contrasting north-facing and south-facing slopes in Tura, central Siberia. We developed chronologies of
tree-ring width for four plots, designated as north-upper, northlower, south-upper, and south-lower. Both residual and standard
chronologies of tree-ring widths exhibited a significant positive correlation with temperature from the end of May until early
June in all four plots. The chronologies of ring width did not reveal any major difference in the response to temperature
among the four plots. The standard chronologies of ring widths on the north-facing slope were negatively correlated with precipitation
during the winter (October–April) and in early and mid-May, whereas the residual chronologies did not reveal clear relationships
with precipitation during the winter and May. The significant correlation between ring width and temperature from the end
of May until early June indicates that temperatures in springtime play a significant role in the radial growth of L. gmelinii. The negative correlations between standard chronologies of tree-ring width and precipitation in the winter and in May on
the north-facing slope indicate that lowfrequency fluctuations in snowfall have negative effects on the radial growth. However,
these effects vary and depend on the microscale topography.
Part of this report was presented at the 55th Annual Meeting of the Japan Wood Society, March 2005, Kyoto 相似文献
120.
Siew Yoong Lee Kent M. Eskridge Woon Yuen Koh Milford A. Hanna 《Industrial Crops and Products》2009,29(2-3):427-436
The aim of this study was to use a supersaturated split-plot design to identify the significant effects of ten ingredients, each at two levels, and two levels of screw speed on selected properties of starch-based packaging foams. Supersaturated designs are special types of fractional factorial designs that allow for evaluating many factors with a minimal amount of experimental material. Rice starch foams were prepared with a twin-screw extruder. The ingredients used were α-cellulose (fiber), potato starch, poly(lactic acid), polystyrene, glycerol, sodium chloride, talc, sodium bicarbonate, citric acid and moisture content of the feed. The properties studied were radial expansion ratio, unit density, bulk spring index, bulk compressibility and Young's modulus. The results showed that the ingredients identified to have significant effects on the properties were the high levels of talc, citric acid, moisture content and the low level of fiber. Low screw speed was found to have greater effect on the properties of the foams than did the high screw speed. It was concluded that the supersaturated split-plot design was successful in identifying the significant ingredients and screw speed that should be used to further investigate the extrusion of starch-based packaging foams. 相似文献