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991.
Yao-Chang Chiang Li-Ci Ye Kuei-Ying Hsu Chien-Wei Liao Tsai-Wei Hung Wan-Jou Lo Ing-Kang Ho Pao-Luh Tao 《Journal of biomedical science》2015,22(1)
Background
Heroin use among young women of reproductive age has drawn much attention around the world. Although methadone is widely used in maintenance therapy for heroin/morphine addiction, the long-term effects of prenatal exposure to methadone and preventative therapy remain unclear. For revealing this question, female pregnant Sprague–Dawley rats were sub-grouped to receive (1) vehicle, (2) methadone 5 mg/kg at embryonic day 3 (E3) and then 7 mg/kg from E4 to E20, (3) dextromethorphan (DM) 3 mg/kg, and (4) methadone + DM (the rats received methadone followed by DM treatment), subcutaneously, twice a day from E3 to E20. The body weight, natural withdrawal, pain sensitivity, ED50, conditioned place preference and water maze were conducted at different postnatal stages (P1 to P79) of offspring. The quantitative real-time RT-PCR and electrophysiology were also used to measure the gene expression of opioid receptors in the spinal cord and changes of LTP/LTD in the hippocampus, separately.Results
Prenatal exposure to methadone or DM did not affect survival rate, body weight, water maze and LTP or LTD of offspring. However, prenatal methadone significantly increased the withdrawal symptoms, pain sensitivity, addiction liability and decreased the mRNA expression of pain related opioid receptors. Co-administration of DM with methadone in the maternal rats effectively prevented these abnormalities of offspring induced by methadone.Conclusions
Our study clearly showed that co-administration of dextromethorphan with methadone in the maternal rats prevented the adverse effects induced by prenatal methadone exposure. It implies that dextromethorphan may have a potential to be used in combination with methadone for maintenance treatment in pregnant heroin-addicted women to prevent the adverse effects induced by methadone on offspring.Electronic supplementary material
The online version of this article (doi:10.1186/s12929-015-0126-2) contains supplementary material, which is available to authorized users. 相似文献992.
993.
Artificial leaf aids analysis of chlorophyll fluorescence and P700 absorbance in studies involving microalgae 下载免费PDF全文
Hongjin Qiao Xiao Fan Dong Xu Naihao Ye Jiying Wang Shaona Cao 《Phycological Research》2015,63(1):72-76
Measuring chlorophyll fluorescence and P700 absorbance has been widely used to study photosynthesis in both terrestrial plants and algae. However, in order to apply these measurement techniques to study microalgae, a concentrated suspension of algae, which is usually prepared by centrifugation, is required. In this study, instead of using centrifugation, we concentrated microalgae on a nitrocellulose membrane using filtration to create an ‘artificial leaf’ before analysis. Overall, we were able to generate values of the appropriate photosynthetic parameters that were comparable to those obtained when chlorophyll fluorescence and P700 absorbance were measured following centrifugation. There were no statistically significant differences (P > 0.05) between the artificial leaf method and the traditional cuvette method for determining chlorophyll fluorescence or P700 absorbance at appropriate chlorophyll concentrations. We were also able to reduce background noise by using a filter membrane as a carrier. Therefore, an artificial leaf has the potential to be a valuable tool for phycologists interested in studying microalgal photosynthesis by enabling them to eliminate tedious centrifugation steps. In addition, fluorometers commonly used for studying the leaves of higher plants will also be suitable for studying microalgae. 相似文献
994.
Kun Yu Jie Gong Chencui Huang Huiyang Huang Haihui Ye Guizhong Wang Chaoshu Zeng 《Cell stress & chaperones》2015,20(5):853-864
995.
Two guard cell mitogen‐activated protein kinases,MPK9 and MPK12, function in methyl jasmonate‐induced stomatal closure in Arabidopsis thaliana 下载免费PDF全文
W. Ye M. A. Hossain M. Uraji Y. Nakamura I. C. Mori J. M. Kwak Y. Murata 《Plant biology (Stuttgart, Germany)》2015,17(5):946-952
Methyl jasmonate (MeJA) and abscisic acid (ABA) signalling cascades share several signalling components in guard cells. We previously showed that two guard cell‐preferential mitogen‐activated protein kinases (MAPKs), MPK9 and MPK12, positively regulate ABA signalling in Arabidopsis thaliana. In this study, we examined whether these two MAP kinases function in MeJA signalling using genetic mutants for MPK9 and MPK12 combined with a pharmacological approach. MeJA induced stomatal closure in mpk9‐1 and mpk12‐1 single mutants as well as wild‐type plants, but not in mpk9‐1 mpk12‐1 double mutants. Consistently, the MAPKK inhibitor PD98059 inhibited the MeJA‐induced stomatal closure in wild‐type plants. MeJA elicited reactive oxygen species (ROS) production and cytosolic alkalisation in guard cells of the mpk9‐1, mpk12‐1 and mpk9‐1 mpk12‐1 mutants, as well in wild‐type plants. Furthermore, MeJA triggered elevation of cytosolic Ca2+ concentration ([Ca2+]cyt) in the mpk9‐1 mpk12‐1 double mutant as well as wild‐type plants. Activation of S‐type anion channels by MeJA was impaired in mpk9‐1 mpk12‐1. Together, these results indicate that MPK9 and MPK12 function upstream of S‐type anion channel activation and downstream of ROS production, cytosolic alkalisation and [Ca2+]cyt elevation in guard cell MeJA signalling, suggesting that MPK9 and MPK12 are key regulators mediating both ABA and MeJA signalling in guard cells. 相似文献
996.
Identifying qualitative effects of different grazing types on below‐ground communities and function in a long‐term field experiment 下载免费PDF全文
Catriona A. Macdonald Michael J. Crawley Denis J. Wright Justin Kuczynski Lucinda Robinson Rob Knight Waleed Abu Al‐Soud Søren J. Sørensen Ye Deng Jizhong Zhou Brajesh K. Singh 《Environmental microbiology》2015,17(3):841-854
Herbivory is an important modulator of plant biodiversity and productivity in grasslands, but our understanding of herbivore‐induced changes on below‐ground processes and communities is limited. Using a long‐term (17 years) experimental site, we evaluated impacts of rabbit and invertebrate grazers on some soil functions involved in carbon cycling, microbial diversity, structure and functional composition. Both rabbit and invertebrate grazing impacted soil functions and microbial community structure. All functional community measures (functions, biogeochemical cycling genes, network association between different taxa) were more strongly affected by invertebrate grazers than rabbits. Furthermore, our results suggest that exclusion of invertebrate grazers decreases both microbial biomass and abundance of genes associated with key biogeochemical cycles, and could thus have long‐term consequences for ecosystem functions. The mechanism behind these impacts are likely to be driven by both direct effects of grazing altering the pattern of nutrient inputs and by indirect effects through changes in plant species composition. However, we could not entirely discount that the pesticide used to exclude invertebrates may have affected some microbial community measures. Nevertheless, our work illustrates that human activity that affects grazing intensity may affect ecosystem functioning and sustainability, as regulated by multi‐trophic interactions between above‐ and below‐ground communities. 相似文献
997.
PsMPK7, a stress‐associated mitogen‐activated protein kinase (MAPK) in Phytophthora sojae,is required for stress tolerance,reactive oxygenated species detoxification,cyst germination,sexual reproduction and infection of soybean 下载免费PDF全文
998.
Elena M. Pugacheva Samuel Rivero-Hinojosa Celso A. Espinoza Claudia Fabiola Méndez-Catalá Sungyun Kang Teruhiko Suzuki Natsuki Kosaka-Suzuki Susan Robinson Vijayaraj Nagarajan Zhen Ye Abdelhalim Boukaba John E. J. Rasko Alexander V. Strunnikov Dmitri Loukinov Bing Ren Victor V. Lobanenkov 《Genome biology》2015,16(1)
999.
1000.