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991.
992.
Maeve O’Leary-Barrett Robert O. Pihl Eric Artiges Tobias Banaschewski Arun L. W. Bokde Christian Büchel Herta Flor Vincent Frouin Hugh Garavan Andreas Heinz Bernd Ittermann Karl Mann Marie-Laure Paillère-Martinot Frauke Nees Tomas Paus Zdenka Pausova Luise Poustka Marcella Rietschel Trevor W. Robbins Michael N. Smolka Andreas Str?hle Gunter Schumann Patricia J. Conrod IMAGEN Consortium 《PloS one》2015,10(6)
Objective
To investigate the role of personality factors and attentional biases towards emotional faces, in establishing concurrent and prospective risk for mental disorder diagnosis in adolescence.Method
Data were obtained as part of the IMAGEN study, conducted across 8 European sites, with a community sample of 2257 adolescents. At 14 years, participants completed an emotional variant of the dot-probe task, as well two personality measures, namely the Substance Use Risk Profile Scale and the revised NEO Personality Inventory. At 14 and 16 years, participants and their parents were interviewed to determine symptoms of mental disorders.Results
Personality traits were general and specific risk indicators for mental disorders at 14 years. Increased specificity was obtained when investigating the likelihood of mental disorders over a 2-year period, with the Substance Use Risk Profile Scale showing incremental validity over the NEO Personality Inventory. Attentional biases to emotional faces did not characterise or predict mental disorders examined in the current sample.Discussion
Personality traits can indicate concurrent and prospective risk for mental disorders in a community youth sample, and identify at-risk youth beyond the impact of baseline symptoms. This study does not support the hypothesis that attentional biases mediate the relationship between personality and psychopathology in a community sample. Task and sample characteristics that contribute to differing results among studies are discussed. 相似文献993.
Traicoff JL Chung JY Braunschweig T Mazo I Shu Y Ramesh A D'Amico MW Galperin MM Knezevic V Hewitt SM 《Journal of biomedical science》2007,14(3):395-405
Summary Alterations in eIF3-p48/INT6 gene expression have been implicated in murine and human mammary carcinogenesis. We examined levels of INT6 protein in human
tumors and determined that breast and colon tumors clustered into distinct groups based on levels of INT6 expression and clinicopathological
variables. We performed multiplex tissue immunoblotting of breast, colon, lung, and ovarian tumor tissues and found that INT6
protein levels positively correlated with those of TID1, Patched, p53, c-Jun, and phosphorylated-c-Jun proteins in a tissue-specific
manner. INT6 and TID1 showed significant positive correlation in all tissue types tested. These findings were confirmed by
immunohistochemical staining of INT6 and TID1. Further evidence supporting a cooperative role for INT6 and TID1 is the presence
of endogenous INT6 and TID1 proteins as complexes. We detected co-immunoprecipitation between INT6 and TID1, as well as between
INT6 and Patched. These findings suggest potential integrated roles for INT6, TID1, and Patched proteins in cell growth, development,
and tumorigenesis. Additionally, these data suggest that the combination of INT6, TID1, and Patched protein levels may be
useful biomarkers for the development of diagnostic assays.
June L. Traico and Joon-Yong Chung contributed equally to this work. 相似文献
994.
DNA interstrand cross-links are formed by chemotherapy drugs as well as by products of normal oxidative metabolism. Despite their importance, the pathways of cross-link metabolism are poorly understood. Laser confocal microscopy has become a powerful tool for studying the repair of DNA lesions that can be detected by immunofluorescent reagents. In order to apply this approach to cross-link repair, we have synthesized conjugates of 4,5',8-trimethylpsoralen (TMP) and easily detected compounds such as Lissamine rhodamine B sulfonyl chloride (LRB-SC), biotin, and digoxigenin. These conjugates are activated by UVA, and we have analyzed the intracellular localization of DNA damage and DNA reactivity by confocal and immunofluorescence microscopy. The LRB-SC-TMP conjugate 2 appeared mainly in the mitochondria, while the biotin-TMP conjugate 4 preferentially localized in the cytoplasm. Adducts formed by UVA and digoxigenin conjugates of TMP 7a and 4,5'-dimethylangelicin (DMA) 7b, which forms only monoadducts, were largely localized to the nucleus. Exposure of cells incubated with 7a and 7b to a 364 nm UV laser directed toward defined nuclear regions of interest resulted in localized adduct formation which could be visualized by immunofluorescence. Repair-proficient cells were able to remove the photoadducts, while repair-deficient cells were unable to repair the damage. The results indicated that the digoxigenin-TMP conjugate 7a and digoxigenin-DMA conjugate 7b can be used for studying the repair of laser localized DNA monoadducts and cross-links. 相似文献
995.
In this study, dieosin glutathione disulfide (Di-E-GSSG) was synthesized by the reaction of eosin isothiocyanate with GSSG. Di-E-GSSG had low fluorescence which increased approximately 70-fold on reduction of its disulfide bond. The substrate was used to monitor the disulfide reductase activity of PDI. Di-E-GSSG is the most sensitive pseudo substrate for PDI reductase activity reported to date. This probe was further used as an analytical reagent to develop an end point assay for measuring the redox state of PDI. The reduction of Di-E-GSSG by reduced enzyme was studied in the absence of reducing agents and the redox state of PDI was monitored as a function of the stoichiometric changes in the amount of eosin-glutathione (EGSH) generated by the active-site dithiols of PDI. The redox state of PDI was also studied under variable [GSH]/[GSSG] ratios. The results indicate that PDI is in approximately 1/2-reduced state where the [GSH]/[GSSG] ratio is between 1:1 and 3:1, conditions similar to the lumen of endoplasmic reticulum or in the extracellular environment. On the other hand, [GSH]/[GSSG] ratios of > or =8:1, such as in cytosol, all active-site thiols would be reduced. The study was extended to utilize Di-E-GSSG to investigate the effect of variable redox ratios on the platelet surface PDI reductase activity. 相似文献
996.
Determination of cholesterol level in blood is important in clinical applications. In this work, modified Au nanowires-electrochemical biosensor based on MEMS micro-fluidic platform is proposed for estimating total cholesterol in blood. This sensor consists of "aligned" Au nanowires as working electrode, platinum counter electrode deposited on the silicon platform and Ag/AgCl (3M KCl) reference electrode. The "aligned" Au nanowires are immobilized with cholesterol oxidase and cholesterol esterase using specific covalent chemistry. Further, Au nanowires promotes better electron transfer between the enzymes and electrodes, because of their large surface to volume ratio, small diffusion time, large electrical conductivity and their aligned nature. The modified Au nanowires showed a stable calibration line and a quasi-linear relationship between cholesterol level and current response in the range of 1-6 mM (in steps of 1 mM over the baseline blood serum). The sensitivity of the modified electrode was found to be about 69 nA/mM with good storage and interference stability. 相似文献
997.
Dharmendra Kumar Ramesh Chand Lal C. Prasad Arun K. Joshi 《World journal of microbiology & biotechnology》2007,23(11):1647-1651
We developed a new technique for monoconidial culture of the most aggressive isolate in a given population of Bipolaris sorokiniana, to facilitate the evaluation of spot blotch resistance in wheat and barley. Blotched portions of infected barley leaves
were placed on a glass slide in a moist chamber for production of conidia by associated fungal hyphae. Conidia were collected
separately and grown on water agar discs. Individual water agar discs having conidium growth were inoculated on barley leaves.
The conidium producing the earliest symptom with the largest lesion was considered most aggressive. This lesion was incubated
in a moist chamber and the conidial offspring were tested for pathogenicity. When a uniform infection was observed, a small
piece of the lesion was cut using a sterilized scalpel, surface sterilized with NaOCl, and inoculated in the centre of Petri
dishes containing potato dextrose agar medium. The inoculated Petri dishes were incubated at 25 ± 1 °C to yield monoconidial
cultures of the most aggressive isolate. Variability in symptom expression caused by the most aggressive isolate of a given
population was much less than variability in symptom expression caused by all isolates collectively. The techniques will be
useful for plant pathologists and breeders in screening for spot blotch resistance in wheat and barley. 相似文献
998.
A study was performed to investigate the efficiency of microbial inoculants after encapsulating in alginate supplemented with humic acid on plant growth. Two promising plant growth promoting rhizobacteria were identified by 16S rDNA sequencing as Pseudomonas putida CC-FR2-4 and Bacillus subtilis CC-pg104, which were further characterized by biochemical analyses and inoculated to Lectuca sativa L. seedlings as free cells and entrapped in beads. Significant increase in shoot height after 21 days of growth was observed with encapsulated CC-pg104 inoculated plants. Highest increase in root length was observed with CC-pg104 free-cell inoculated plants, followed by plants inoculated with encapsulated CC-pg104. Results clearly demonstrated that inoculation of the encapsulated bacterial isolates promoted plant growth similar to their respective free cells and could be a novel and feasible technique for application in agricultural industry. 相似文献
999.
Plastid DNA is absent in pollen or sperm cells of Arabidopsis thaliana. Accordingly, plastids and mitochondria, in a standard genetic cross, are transmitted to the seed progeny by the maternal parent only. Our objective was to test whether paternal plastids are transmitted by pollen as an exception. The maternal parent in our cross was a nuclear male sterile (ms1-1/ms1-1), spectinomycin-sensitive Ler plant. It was fertilized with pollen of a male fertile RLD-Spc1 plant carrying a plastid-encoded spectinomycin resistance mutation. Seedlings with paternal plastids were selected by spectinomycin resistance encoded in the paternal plastid DNA. Our data, in general, support maternal inheritance of plastids in A. thaliana. However, we report that paternal plastids are transmitted to the seed progeny in Arabidopsis at a low (3.9 x 10(-5)) frequency. This observation extends previous reports in Antirrhinum majus, Epilobium hirsutum, Nicotiana tabacum, Petunia hybrida, and the cereal crop Setaria italica to a cruciferous species suggesting that low-frequency paternal leakage of plastids via pollen may be universal in plants previously thought to exhibit strict maternal plastid inheritance. The genetic tools employed here will facilitate testing the effect of Arabidopsis nuclear mutations on plastid inheritance and allow for the design of mutant screens to identify nuclear genes controlling plastid inheritance. 相似文献
1000.
Sethi A Maurya A Tewari V Srivastava S Faridi S Bhatia G Khan MM Khanna AK Saxena JK 《Bioorganic & medicinal chemistry》2007,15(13):4520-4527
A series of new pregnane derivatives and its glycosides were synthesized in order to find new 'leads' against some important targets. The 3beta-hydroxy-16alpha-(2-hydroxy ethoxy) pregn-5-en-20-one (5) was synthesized from 3beta-hydroxy-5,16-pregnadiene-20-one (2) by adopting general modified procedure using BF(3):Et(2)O as a catalyst. Reduction of 5, with sodium borohydride yielded 3beta,20beta-dihydroxy-16alpha-(2-hydroxy ethoxy) pregn-5-en (7) as the major isolable product. O-alkylation of the C-20-oxime-pregnadiene (9) with 1,5-dibromopentane yielded 20-(O-5-bromopentyl)-oximino-3beta-hydroxy-pregn-5,16-diene (11). Synthesis of C-16 substituted pregnane glycosides (20) and (21) were accomplished with the imidate method using BF(3):Et(2)O. The synthesis of 4-chlorobenzoate (3) and 2-chlorobenzoate (4), derivatives of 2 were also accomplished. These compounds were evaluated for their anti-dyslipidemic and anti-oxidant activity and amongst them compounds 3 and 7 showed more lipid lowering and anti-oxidant activity. 相似文献