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101.
Hejun Liu Xiaoyu Zhao Gui Xue Chuansheng Chen Qi Dong Xuping Gao Li Yang Chunhui Chen 《Genes, Brain & Behavior》2023,22(1):e12835
Genetic studies on attention have mainly focused on children with attention-deficit/hyperactivity disorder (ADHD), so little systematic research has been conducted on genetic correlates of attention performance and their potential brain mechanisms among healthy individuals. The current study included a genome-wide association study (GWAS, N = 1145 healthy young adults) aimed to identify genes associated with sustained attention and an imaging genetics study (an independent sample of 483 healthy young adults) to examine any identified genes' influences on brain function. The GWAS found that TTLL11 showed genome-wide significant associations with sustained attention, with rs13298112 as the most significant SNP and the GG homozygotes showing more impulsive but also more focused responses than the A allele carriers. A retrospective examination of previously published ADHD GWAS results confirmed an un-reported, small but statistically significant effect of TTLL11 on ADHD. The imaging genetics study replicated this association and showed that the TTLL11 gene was associated with resting state activity and connectivity of the somatomoter network, and can be predicted by dorsal attention network connectivity. Specifically, the GG homozygotes showed lower brain activity, weaker brain network connectivity, and non-significant brain-attention association compared to the A allele carriers. Expression database showed that expression of this gene is enriched in the brain and that the G allele is associated with lower expression level than the A allele. These results suggest that TTLL11 may play a major role in healthy individuals' attention performance and may also contribute to the etiology of ADHD. 相似文献
102.
Four new germacrane-type sesquiterpenes commiphoranes M1-M4 ( 1 - 4 ) together with eighteen sesquiterpenes were isolated from the Resina Commiphora. The structures and relative configurations of new substances were determined by using spectroscopic methods. Biological activity investigation revealed that nine compounds including 7 , 9 , 14 , 16 , (+)- 17 , (−)- 17 , 18 , 19 , and 20 could induce the apoptosis of prostate cancer originated PC-3 cells, through classic apoptosis signaling pathway, even using flow cytometry showed that the compound (+)- 17 caused apoptosis of PC-3 cells more than 40 %, suggesting their potential therapeutic application in the development of novel drugs against prostate cancer. 相似文献
103.
104.
Zhigao Wang Yidan Hu Yiran Dong Liang Shi Yongguang Jiang 《Microbial biotechnology》2023,16(3):534-545
Protein nanowires are critical electroactive components for electron transfer of Geobacter sulfurreducens biofilm. To determine the applicability of the nanowire proteins in improving bioelectricity production, their genes including pilA, omcZ, omcS and omcT were overexpressed in G. sulfurreducens. The voltage outputs of the constructed strains were higher than that of the control strain with the empty vector (0.470–0.578 vs. 0.355 V) in microbial fuel cells (MFCs). As a result, the power density of the constructed strains (i.e. 1.39–1.58 W m−2) also increased by 2.62- to 2.97-fold as compared to that of the control strain. Overexpression of nanowire proteins also improved biofilm formation on electrodes with increased protein amount and thickness of biofilms. The normalized power outputs of the constructed strains were 0.18–0.20 W g−1 that increased by 74% to 93% from that of the control strain. Bioelectrochemical analyses further revealed that the biofilms and MFCs with the constructed strains had stronger electroactivity and smaller internal resistance, respectively. Collectively, these results demonstrate for the first time that overexpression of nanowire proteins increases the biomass and electroactivity of anode-attached microbial biofilms. Moreover, this study provides a new way for enhancing the electrical outputs of MFCs. 相似文献
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107.
SEO Dong-Hwan† Seock-Yeon HWANG† Jikhyon HAN Sang-Kyun KOH Iksoo KIM Kang Sun RYU Chi-Young YUN 《Entomological Research》2004,34(3):207-211
This study was performed to explore novel and valuable uses of insect resources, important subjects of the natural compound used in bio‐industries. The whole bodies of two crickets, Gryllus bimaculatus and Teleogryllus emma, selected from medicinal insect species, were carefully ground and treated with 80% EtOH. The insect extracts were solubilized and separated by hexane, butanol, and D.W according to their polarities. Three types of extracts, a D.W fraction (G1) and a boiling extract (G2) of an introduced cricket, G. bimaculatus, and a D.W fraction (T1) of a Korean local cricket, T. emma, were prepared to assay immune stimulating activity of cricket originated compounds. The all of three treated cricket extracts showed to increase IL‐4, IFN‐, and TNF‐α. Among those extract, extract G2, boiled extract from G. bimaculatus, was the best immune–enhancing fraction. The results of this study could be fundamental information for further works to use insects as natural resources having plenty of potentials and varieties. 相似文献
108.
The application of sensory methodology for measuring deodorizing effect of an air conditioner equipped with electric plasma was introduced. Deodorizing effect was measured using chemical and sensory methods at different time (0, 30 and 60 min) and mode (control, blowing and cooling) of an air conditioner. Smoke from a roll of cigarette in a closed room was used as a source of odor and the concentrations of acetic acid and ammonia were measured as odorous chemical components. As one of the sensory methods triangle test was used and as a first step to obtain deodorizing effects by triangle test, the threshold of each panelist was obtained as the log dilution ratio of odor concentration at which the difference from odorless air was detected. The odor concentration at each time and mode was calculated using the threshold of the panel and the deodorizing effect was obtained on the basis of the odor concentration. In addition to a triangle test, scaling methods such as category scaling or magnitude estimation were used to measure deodorizing effect of an air conditioner. Deodorizing effects by scaling methods were calculated based on odor intensity with time at each mode. The regression analysis was done between the efficacy of deodorizing effect by sensory test and those by acetic acid and ammonia, the R2 values of the regression equations for triangle test, category scale, and magnitude estimation were 0.84, 0.72 and 0.69, respectively. Deodorizing effect by triangle test explained the decrease of acetic acid and ammonia better than those by category scaling or magnitude estimation while high cost and time consuming labor involved in triangle tests reduced the merit. The results of this study demonstrated that various sensory methods could be used to measure deodorizing effect of air conditioners and further researches on fast and reliable methods are needed to establish the official procedures. 相似文献
109.
A multistage affinity cross-flow filtration (mACFF) process for protein purification is proposed. The process is mathematically modelled taking into account a case of rapid equilibrium binding of a target protein to its macroligand. The process performance, i.e., dimensionless breakthrough volume (Q b + )and recovery yield (REC) to obtain a desired purity is analysed by computer simulations. The results indicate that Q b + increases with the increase of stage number (n) due to the increase of affinity binding efficiency. In addition, REC also increases with the increase of n, especially for lower affinity systems, even though the feed loading is the same as the corresponding breakthrough volume that increases with n. Thus both feed loading and recovery yield can be enhanced by raising the stage number. Incompletely permeable membranes reject the target and contaminant proteins. So they delay the appearance of the breakthrough point and compromise the contaminant washing efficiency. Hence although Q b + increases with the increase of membrane rejection coefficient (R), REC decreases when the feed loading equals that of Q b + . However, when the feed loading is kept unchanged and equals Q b + at R=0, REC does not decrease, but slightly increases with the increase of R. This result indicates that incompletely permeable membranes may also be employed for the mACFF process. In general, the model gives a predictive evaluation of the mACFF process successfully. 相似文献
110.
为研究水稻蜡质基因(waxy)5'上游调控区中存在的顺式作用元件,我们将水稻waxy基因翻译起始声、(ATG)5'上游3.4kb(-2118~+1291bP)片段经外切核酸酶ExoⅢ部分酶解,得到一系列5'端缺失的片段。将这些缺失片段分别与gus基因编码区连接,构建成融合质粒,经PEG介导引入水稻原生质体,26℃培养48h后,定量测定GUS酶活力,并以同时导入的由35S启动子指导的荧光素酶(LUC)基因表达的酶活力作为内对照。结果表明,GUS酶活性随5’上游调控区长度的减少而逐渐减弱。由─861bp缺失至─640bP时,gus基因表达水平有较明显的降低,推测在该区域中可能存在一个顺式作用元件区。 相似文献