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131.
Pitna Kim Jin Hee Park Chang Soon Choi Inah Choi So Hyun Joo Min Kyoung Kim Soo Young Kim Ki Chan Kim Seung Hwa Park Kyoung Ja Kwon Jongmin Lee Seol-Heui Han Jong Hoon Ryu Jae Hoon Cheong Jung Yeol Han Ki Narm Ko Chan Young Shin 《Neurochemical research》2013,38(3):620-631
Prenatal exposure to alcohol has consistently been associated with adverse effects on neurodevelopment, which is collectively called fetal alcohol spectrum disorder (FASD). Increasing evidence suggest that prenatal exposure to alcohol increases the risk of developing attention deficit/hyperactivity disorder-like behavior in human. In this study, we investigated the behavioral effects of prenatal exposure to EtOH in offspring mice and rats focusing on hyperactivity and impulsivity. We also examined changes in dopamine transporter and MeCP2 expression, which may underlie as a key neurobiological and epigenetic determinant in FASD and hyperactive, inattentive and impulsive behaviors. Mouse or rat offspring born from dam exposed to alcohol during pregnancy (EtOH group) showed hyper locomotive activity, attention deficit and impulsivity. EtOH group also showed increased dopamine transporter and norepinephrine transporter level compared to control group in the prefrontal cortex and striatum. Prenatal exposure to EtOH also significantly decreased the expression of MeCP2 in both prefrontal cortex and striatum. These results suggest that prenatal exposure to EtOH induces hyperactive, inattentive and impulsive behaviors in rodent offspring that might be related to global epigenetic changes as well as aberration in catecholamine neurotransmitter transporter system. 相似文献
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133.
To elucidate the bacterial diversity in biofilms formed on a condenser tube from a nuclear power plant, 16S rRNA gene sequences were examined using a PCR-cloning-sequencing approach. Twelve operational taxonomic units were retrieved in the clone library, and the estimated species richness was low (13.2). Most of the clones (94.7%) were affiliated with α-Proteobacteria; Planctomycetes and γ-Proteobacteria were much rarer. Interestingly, except for one clone belonging to Pseudoalteromonas, most of the sequences displayed sequence similarities <97% of those of the closest type strains. Based on 16S rRNA phylogenetic analysis, most bacteria were assigned to novel taxa above the species level. The low species richness and unusual bacterial composition may be attributable to selective pressure from chlorine in the cooling water. To prevent or control bacterial biofilms in cooling circuits, additional studies of the physiology and ecology of these species will be essential. 相似文献
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135.
Ellen H. Esch Daniel L. Hernández Jae R. Pasari Rose S. G. Kantor Paul C. Selmants 《Plant and Soil》2013,366(1-2):671-682
Background and aims
Exotic species, nitrogen (N) deposition, and grazing are major drivers of change in grasslands. However little is known about the interactive effects of these factors on below-ground microbial communities.Methods
We simulated realistic N deposition increases with low-level fertilization and manipulated grazing with fencing in a split-plot experiment in California’s largest serpentine grassland. We also monitored grazing intensity using camera traps and measured total available N to assess grazing and nutrient enrichment effects on microbial extracellular enzyme activity (EEA), microbial N mineralization, and respiration rates in soil.Results
Continuous measures of grazing intensity and N availability showed that increased grazing and N were correlated with increased microbial activity and were stronger predictors than the categorical grazing and fertilization measures. Exotic cover was also generally correlated with increased microbial activity resulting from exotic-driven nutrient cycling alterations. Seasonal effects, on abiotic factors and plant phenology, were also an important factor in EEA with lower activity occurring at peak plant biomass.Conclusions
In combination with previous studies from this serpentine grassland, our results suggest that grazing intensity and soil N availability may affect the soil microbial community indirectly via effects on exotic cover and associated changes in nutrient cycling while grazing directly impacts soil community function. 相似文献136.
Osmotin or osmotin-like protein, a PR-5 family member, is differentially induced in plants by abiotic and biotic stresses. Here, we demonstrate that the pepper (Capsicum annuum) osmotin-like protein 1 gene, CaOSM1, was required for the defense and hypersensitive cell death response and oxidative burst signaling during Xanthomonas campestris pv. vesicatoria (Xcv) infection. CaOSM1 protein was localized to the plasma membrane in leaf cells of Nicotiana benthamiana. Agrobacterium-mediated transient expression of CaOSM1 in pepper distinctly induced the hypersensitive cell death response and H2O2 accumulation. Knock-down of CaOSM1 in pepper by virus-induced gene silencing increased the susceptibility to Xcv infection, which was accompanied by attenuation of the cell death response and decreased accumulation of H2O2. CaOSM1 overexpression in transgenic Arabidopsis conferred reduced susceptibility and accelerated cell death response and H2O2 accumulation to infection by Pseudomonas syringe pv. tomato and Hyaloperonospora arabidopsidis. Together, these results suggest that CaOSM1 is involved in cell death and oxidative burst responses during plant defense against microbial pathogens. 相似文献
137.
Hyo Jae Kang Young Sik Park Chang-Hoon Lee Sang-Min Lee Jae-Joon Yim Chul-Gyu Yoo Young Whan Kim Sung Koo Han Jong-Yil Chai Jinwoo Lee 《The Korean journal of parasitology》2013,51(5):569-572
Dirofilariasis is a rare disease in humans. We report here a case of a 48-year-old male who was diagnosed with pulmonary dirofilariasis in Korea. On chest radiographs, a coin lesion of 1 cm in diameter was shown. Although it looked like a benign inflammatory nodule, malignancy could not be excluded. So, the nodule was resected by video-assisted thoracic surgery. Pathologically, chronic granulomatous inflammation composed of coagulation necrosis with rim of fibrous tissues and granulations was seen. In the center of the necrotic nodules, a degenerating parasitic organism was found. The parasite had prominent internal cuticular ridges and thick cuticle, a well-developed muscle layer, an intestinal tube, and uterine tubules. The parasite was diagnosed as an immature female worm of Dirofilaria immitis. This is the second reported case of human pulmonary dirofilariasis in Korea. 相似文献
138.
Chinese hamster ovary (CHO) cells, that are widely used for production of therapeutic proteins, are subjected to apoptosis and autophagy under the stresses induced by conditions such as nutrient deprivation, hyperosmolality and addition of sodium butyrate. To achieve a cost-effective level of production, it is important to extend the culture longevity. Until now, there have been numerous studies in which apoptosis of recombinant CHO (rCHO) cells was inhibited, resulting in enhanced production of therapeutic proteins. Recently, autophagy in rCHO cells has drawn attention because it can be genetically and chemically controlled to increase cell survival and productivity. Autophagy is a global catabolic process which involves multiple pathways and genes that regulate the lysosomal degradation of intracellular components. A simultaneous targeting of anti-apoptosis and pro-autophagy could lead to more efficient protection of cells from stressful culture conditions. In this regard, it is worthwhile to have a detailed understanding of the autophagic pathway, in order to select appropriate genes and chemical targets to manage autophagy in rCHO cells, and thus to enhance the production of therapeutic proteins. 相似文献
139.
Sowbiya Muneer Bok Rye Lee Dong Won Bae Tae Hwan Kim 《Acta Physiologiae Plantarum》2013,35(10):3037-3045
In order to characterize the significance of sulfur (S) nutrition in protein expression under iron (Fe)-deficient conditions, gel-based proteomic analysis was performed with the leaves of Brassica napus exposed to S and Fe combined treatments: sufficient in S and Fe (+S/+Fe, control), sufficient S but Fe deprived (+S/?Fe), deprived S but sufficient Fe (?S/+Fe), and deprived S and Fe (?S/?Fe). The resulting data showed that 15 proteins were down-regulated due to production of oxidative damage as indicated by H2O2 and O 2 ?1 localizations and due to leaf chlorosis in leaves in S-deprived leaves either in presence (?S/+Fe) or absence of Fe (?S/?Fe), whereas these down-regulated proteins were well expressed in the presence of S (+S/?Fe) compared to control (+S/+Fe). In addition, two proteins were up-regulated under S-deprived condition in presence (?S/+Fe) and absence of (?S/?Fe) Fe. The functional classification of these identified proteins was estimated that 40 % of the proteins belong to chloroplast precursor, and rest of the proteins belongs to hypothetical proteins, RNA binding, secondary metabolism and unknown proteins. On the other hand, five protein spots from S deprived (?S/+Fe) and ten spots from Fe deprived (?S/?Fe) conditions were absent, whereas they were well expressed in presence of S (+S/?Fe) compared to control plants (+S/+Fe). These results suggest that sulfur nutrition plays an important role in alleviating protein damage in Fe-deficient plants and adaptation to Fe-deficiency in oilseed rape. 相似文献
140.
Seung Hwan Lee Kyoung-Hee Kang Eun Young Kim Tong Un Chae Young Hoon Oh Soon Ho Hong Bong Keun Song Jonggeon Jegals Si Jae Park Sang Yup Lee 《Biotechnology letters》2013,35(10):1631-1637
We have previously analyzed the proteome of recombinant Escherichia coli producing poly(3-hydroxybutyrate) [P(3HB)] and revealed that the expression level of several enzymes in central metabolism are proportional to the amount of P(3HB) accumulated in the cells. Based on these results, the amplification effects of triosephosphate isomerase (TpiA) and fructose-bisphosphate aldolase (FbaA) on P(3HB) synthesis were examined in recombinant E. coli W3110, XL1-Blue, and W lacI mutant strains using glucose, sucrose and xylose as carbon sources. Amplification of TpiA and FbaA significantly increased the P(3HB) contents and concentrations in the three E. coli strains. TpiA amplification in E. coli XL1-Blue lacI increased P(3HB) from 0.4 to 1.6 to g/l from glucose. Thus amplification of glycolytic pathway enzymes is a good strategy for efficient production of P(3HB) by allowing increased glycolytic pathway flux to make more acetyl-CoA available for P(3HB) biosynthesis. 相似文献