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961.
962.
Elevated temperature is more effective than elevated [CO2] in exposing genotypic variation in Telopea speciosissima growth plasticity: implications for woody plant populations under climate change 下载免费PDF全文
Guomin Huang Paul D. Rymer Honglang Duan Renee A. Smith David T. Tissue 《Global Change Biology》2015,21(10):3800-3813
Intraspecific variation in phenotypic plasticity is a critical determinant of plant species capacity to cope with climate change. A long‐standing hypothesis states that greater levels of environmental variability will select for genotypes with greater phenotypic plasticity. However, few studies have examined how genotypes of woody species originating from contrasting environments respond to multiple climate change factors. Here, we investigated the main and interactive effects of elevated [CO2] (CE) and elevated temperature (TE) on growth and physiology of Coastal (warmer, less variable temperature environment) and Upland (cooler, more variable temperature environment) genotypes of an Australian woody species Telopea speciosissima. Both genotypes were positively responsive to CE (35% and 29% increase in whole‐plant dry mass and leaf area, respectively), but only the Coastal genotype exhibited positive growth responses to TE. We found that the Coastal genotype exhibited greater growth response to TE (47% and 85% increase in whole‐plant dry mass and leaf area, respectively) when compared with the Upland genotype (no change in dry mass or leaf area). No intraspecific variation in physiological plasticity was detected under CE or TE, and the interactive effects of CE and TE on intraspecific variation in phenotypic plasticity were also largely absent. Overall, TE was a more effective climate factor than CE in exposing genotypic variation in our woody species. Our results contradict the paradigm that genotypes from more variable climates will exhibit greater phenotypic plasticity in future climate regimes. 相似文献
963.
Construction of a cell‐surface display system based on the N‐terminal domain of ice nucleation protein and its application in identification of mycoplasma adhesion proteins 下载免费PDF全文
964.
Another functional frame‐shift polymorphism of DEFB126 (rs11467497) associated with male infertility 下载免费PDF全文
Shiwei Duan Changgeng Shi Guowu Chen Ju‐fen Zheng Bin Wu Hua Diao Lindan Ji Yihua Gu Aijie Xin Yancheng Wu Weijin Zhou Maohua Miao Limin Xu Zheng Li Yao Yuan Peng Wang Huijuan Shi 《Journal of cellular and molecular medicine》2015,19(5):1077-1084
DEFB126 rs140685149 mutation was shown to cause sperm dysfunction and subfertility. Indel rs11467497 is another 4‐nucleotide frame‐shift mutation (151bp upstream of rs140685149) that leads to the premature termination of translation and the expression of peptide truncated at the carboxyl terminus. In the present study, we performed a comprehensive association study to check the contribution of rs140685149 and rs11467497 to male infertility. Our results confirmed the previous findings that there was no association between rs140685149 and sperm motility. In contrast, we found a significant association of another indel rs11467497 with male infertility. Moreover, rs11467497 was shown to be associated with higher number of round cells in the infertile males with low sperm motility. Surprisingly, the two mutations commonly existed in the sperm donors (n = 672), suggesting a potential application of the two indels in the screening for eligible sperm donors. Western blotting assays showed the sperms with rs140685149 2‐nt deletion tended to have unstable DEFB126 protein in contrast of no DEFB126 protein expressed in the sperms with rs11467497 4‐nt deletion, suggesting a more severe consequence caused by rs11467497 mutation. In conclusion, our study presented a significant contribution of another functional frame‐shift polymorphism of DEFB126 (rs11467497) to male infertility. 相似文献
965.
966.
Sheng Chen Jingjing Duan Pengju Bian Youhong Tang Rongkun Zheng Shi‐Zhang Qiao 《Liver Transplantation》2015,5(18)
A multifunctional catalyst electrode mimicking external stimuli–responsive property has been prepared by the in situ growth of nitrogen (N)‐doped NiFe double layered hydroxide (N–NiFe LDH) nanolayers on a 3D nickel foam substrate framework. The electrode demonstrates superior performance toward catalyzing oxygen evolution reaction (OER), affording a low overpotential of 0.23 V at the current density of 10 mA cm?2, high Faradaic efficiency of ≈98%, and stable operation for >60 h. Meanwhile, the electrode can dynamically change its color from gray silver to dark black with the OER happening, and the coloration/bleaching processes persist for at least 5000 cycles, rendering it a useful tool to monitor the catalytic process. Mechanism study reveals that the excellent structural properties of electrode such as 3D conductive framework, ultra thickness of N–NiFe LDH nanolayer (≈0.8 nm), and high N‐doping content (≈17.8%) make significant contribution to achieving enhanced catalytic performance, while N–NiFe LDH nanolayer on electrode is the main contributor to the stimuli‐responsive property with the reversible extraction/insertion of electrons from/into N–NiFe LDH leading to the coloration/bleaching processes. Potential application of this electrode has been further demonstrated by integrating it into a Zn–air battery device to identify the charging process during electrochemical cycling. 相似文献
967.
T. Wiltshire R. B. Ervin H. Duan M. A. Bogue W. C. Zamboni S. Cook W. Chung F. Zou L. M. Tarantino 《Genes, Brain & Behavior》2015,14(3):271-280
Initial sensitivity to psychostimulants can predict subsequent use and abuse in humans. Acute locomotor activation in response to psychostimulants is commonly used as an animal model of initial drug sensitivity and has been shown to have a substantial genetic component. Identifying the specific genetic differences that lead to phenotypic differences in initial drug sensitivity can advance our understanding of the processes that lead to addiction. Phenotyping inbred mouse strain panels are frequently used as a first step for studying the genetic architecture of complex traits. We assessed locomotor activation following a single, acute 20 mg/kg dose of cocaine (COC) in males from 45 inbred mouse strains and observed significant phenotypic variation across strains indicating a substantial genetic component. We also measured levels of COC, the active metabolite, norcocaine and the major inactive metabolite, benzoylecgonine, in plasma and brain in the same set of inbred strains. Pharmacokinetic (PK) and behavioral data were significantly correlated, but at a level that indicates that PK alone does not account for the behavioral differences observed across strains. Phenotypic data from this reference population of inbred strains can be utilized in studies aimed at examining the role of psychostimulant‐induced locomotor activation on drug reward and reinforcement and to test theories about addiction processes. Moreover, these data serve as a starting point for identifying genes that alter sensitivity to the locomotor stimulatory effects of COC. 相似文献
968.
Zhenglu Deng Siyu Yan Hui Hu Zhigui Duan Lanxuan Yin Shenke Liao Yubai Sun Dazhong Yin Guolin Li 《Proteomics》2015,15(1):148-159
To investigate biochemical mechanisms for the tetracycline‐induced steatosis in rats, targeted proteins of oxidative modification were profiled. The results showed that tetracycline induced lipid accumulation, oxidative stress, and cell viability decline in HepG2 cells only under the circumstances of palmitic acid overload. Tetracycline administration in rats led to significant decrement in blood lipids, while resulted in more than four times increment in intrahepatic triacylglycerol and typical microvesicular steatosis in the livers. The triacylglycerol levels were positively correlated with oxidative stress. Proteomic profiles of carbonylated proteins revealed 26 targeted proteins susceptible to oxidative modification and most of them located in mitochondria. Among them, the long‐chain specific acyl‐CoA dehydrogenase was one of the key enzymes regulating fatty acid β‐oxidation. Oxidative modification of the enzyme in the tetracycline group depressed its enzymatic activity. In conclusion, the increased influx of lipid into the livers is the first hit of tetracycline‐induced microvesicular steatosis. Oxidative stress is an essential part of the second hit, which may arise from the lipid overload and attack a series of functional proteins, aggravating the development of steatosis. The 26 targeted proteins revealed here provide a potential direct link between oxidative stress and tetracycline‐induced steatosis. 相似文献
969.
Trinary Layered Double Hydroxides as High‐Performance Bifunctional Materials for Oxygen Electrocatalysis 下载免费PDF全文
Li Qian Zhiyi Lu Tianhao Xu Xiaochao Wu Yang Tian Yaping Li Ziyang Huo Xiaoming Sun Xue Duan 《Liver Transplantation》2015,5(13)
Layered double hydroxides (LDHs) are a family of high‐profile layer materials with tunable metal species and interlayer spacing, and herein the LDHs are first investigated as bifunctional electrocatalysts. It is found that trinary LDH containing nickel, cobalt, and iron (NiCoFe‐LDH) shows a reasonable bifunctional performance, while exploiting a preoxidation treatment can significantly enhance both oxygen reduction reaction and oxygen evolution reaction activity. This phenomenon is attributed to the partial conversion of Co2+ to Co3+ state in the preoxidation step, which stimulates the charge transfer to the catalyst surface. The practical application of the optimized material is demonstrated with a small potential hysteresis (800 mV for a reversible current density of 20 mA cm?2) as well as a high stability, exceeding the performances of noble metal catalysts (commercial Pt/C and Ir/C). The combination of the electrochemical metrics and the facile and cost‐effective synthesis endows the trinary LDH as a promising bifunctional catalyst for a variety of applications, such as next‐generation regenerative fuel cells or metal–air batteries. 相似文献
970.
Yu-xing?Jin Ge-ning?JiangEmail author Hui?Zheng Liang?Duan Jia-an?Ding 《Molecular genetics and genomics : MGG》2015,290(2):573-584
The association between common variations (rs10937405, rs4488809) on 3q28 and lung cancer has been widely evaluated in various ethnic groups, since it was first identified through genome-wide association approach. However, the results have been inconclusive. To derive a more precise estimation of the relationship and the effect of factors that might modify the risk, we performed this meta-analysis. The random-effects model was applied, addressing heterogeneity and publication bias. A total of 10 articles involving 36,221 cases and 58,108 controls were included. Overall, the summary per-allele OR of 1.19 (95 % CI 1.14–1.25, P < 10?5) and 1.17 (95 % CI 1.10–1.23, P < 10?5) was found for the rs10937405 and rs4488809 polymorphisms, respectively. Significant results were also observed in heterozygous and homozygous when compared with wild genotype for these polymorphisms. Significant results were found in East Asians when stratified by ethnicity, whereas no significant associations were found among Caucasians. After stratifying by sample size, study design, control source and sex, significant associations were also obtained. In addition, our data indicate that these polymorphisms are involved in lung cancer susceptibility and confer its effect primarily in lung adenocarcinoma when stratified by histological subtype. Furthermore, significant associations were also detected both never-smokers and smokers for these polymorphisms. In conclusion, this meta-analysis demonstrated that rs10937405 and rs4488809 are a risk factor associated with increased non-small cell lung cancer susceptibility, particularly for East Asian populations. 相似文献