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951.
When people are confronted with feedback that counters their prior beliefs, they preferentially rely on desirable rather than undesirable feedback in belief updating, i.e. an optimism bias. In two pre-registered EEG studies employing an adverse life event probability estimation task, we investigated the neurocognitive processes that support the formation and the change of optimism biases in immediate and 24 h delayed tests. We found that optimistic belief updating biases not only emerged immediately but also became significantly larger after 24 h, suggesting an active role of valence-dependent offline consolidation processes in the change of optimism biases. Participants also showed optimistic memory biases: they were less accurate in remembering undesirable than desirable feedback probabilities, with inferior memories of undesirable feedback associated with lower belief updating in the delayed test. Examining event-related brain potentials (ERPs) revealed that desirability of feedback biased initial encoding: desirable feedback elicited larger P300s than undesirable feedback, with larger P300 amplitudes predicting both higher belief updating and memory accuracies. These results suggest that desirability of feedback could bias both online and offline memory-related processes such as encoding and consolidation, with both processes contributing to the formation and change of optimism biases. 相似文献
952.
A general psychopathology (‘p’) factor captures shared variation across mental disorders. One hypothesis is that poor executive function (EF) contributes to p. Although EF is related to p concurrently, it is unclear whether EF predicts or is a consequence of p. For the first time, we examined prospective relations between EF and p in 9845 preadolescents (aged 9–12) from the Adolescent Brain Cognitive Development Study® longitudinally over two years. We identified higher-order factor models of psychopathology at baseline and one- and two-year follow-up waves. Consistent with previous research, a cross-sectional inverse relationship between EF and p emerged. Using residualized-change models, baseline EF prospectively predicted p factor scores two years later, controlling for prior p, sex, age, race/ethnicity, parental education, and family income. Baseline p factor scores also prospectively predicted change in EF two years later. Tests of specificity revealed that bi-directional prospective relations between EF and p were largely generalizable across externalizing, internalizing, neurodevelopmental, somatization, and detachment symptoms. EF consistently predicted change in externalizing and neurodevelopmental symptoms. These novel results suggest that executive dysfunction is both a risk marker and consequence of general psychopathology. EF may be a promising transdiagnostic intervention target to prevent the onset and maintenance of psychopathology. 相似文献
953.
目的通过应用多重连接依赖式探针扩增(MLPA)技术对3例猫叫综合征(CDCS,5p缺失综合征)进行分析,旨在探索可快速诊断CDCS的分子遗传学方法。方法对3个CDCS患者及其父母、患者1的异卵双生之姐姐,进行MLPA分析,检测CDCS关键区域5p15.33:包括hTERT基因在内的9个位点的基因拷贝数的变化;同时,对相应标本进行染色体G-显带核型分析。结果在接到标本24—48h,MLPA示:3例患儿均存在CDCS关键区域5p15.33包含hTERT在内的基因缺失,其父母及患者1异卵双生之姐姐未见缺失。7—10天后G显带染色体核型分析示:患儿2、3为单纯5号短臂(5p)末端缺失,其父母正常;患儿1病例在国内尚属少见,核型为:45,XY,-22,-5p,4-der(5)t(5;22),携带了一条源于5p和22p易位而来衍生的5号染色体,其父母及异卵双生之姐姐均正常。MLPA与核型分析结果-致:3例患儿均为CDCS患者。结论MLPA是-种可快速诊断CDCS的分子遗传学方法,具有临床应用价值。 相似文献
954.
955.
Sang Hwa Lee Hyunkyung Kim Wook Youn Kim Hye Seung Han So Dug Lim Wan Seop Kim Sehun Kim Tae Sook Hwang 《Pathology international》2013,63(5):252-259
We evaluated p53, KRAS, BRAF and CTNNB1 mutation and p53, WT1, p16 and beta‐catenin expression in 31 ovarian high‐grade serous adenocarcinoma. Twenty‐five (80.6%) tumors contained functional mutations of p53; three frameshift, four nonsense and 19 missense mutations. None of the tumors showed KRAS, BRAF or CTNNB1 mutation. In all 18 tumors with missense mutations, ≥60% of tumor cells were strongly positive for p53 immunostaining whereas all tumors with frameshift or nonsense mutations were completely negative. Missense mutation was correlated with diffuse and strong imunoreaction and frameshift/nonsense mutation was correlated with completely negative immunoreaction (P = 0.000). Tumors with wild‐type p53 revealed a wide range of immunostaining patterns. In 27 (87.1%) and 18 (58.1%) tumors, ≥50% of tumor cells were moderate to strongly positive for WT1 and p16, respectively. A considerable intratumoral heterogeneity for p16 expression was present. None of the tumors demonstrated nuclear beta‐catenin expression. p53 mutations appear to be a powerful molecular marker for ovarian high‐grade serous adenocarcinoma. Using p53 with an appropriate interpretation criteria together with WT1, p16 and beta‐catenin, most of the high‐grade serous adenocarcinoma could be distinguished from other ovarian tumors. 相似文献
956.
Inken Padberg Sabrina Janßen Thomas F. Meyer 《International journal of medical microbiology : IJMM》2013,303(8):463-474
Epidemiological data exist to support a positive association between Chlamydia trachomatis (Ctr) infection and gynecological cancers; however, putative cellular mechanisms for this association are lacking. Here, we identified Ctr-induced perturbations to host cell phenotypes in vitro that persisted after clearance of infection and could directly contribute to host cell transformation. In particular, human telomerase catalytic subunit (hTERT) mRNA expression and catalytic subunit activity were increased in acute infected late passage IMR90E1A cells. hTERT upregulation was accompanied by recruitment of ceramide, a known regulator of hTERT, to the chlamydial inclusion and was abrogated following doxycycline-mediated infection clearance. In cells cleared of Ctr infection, average telomere length was slightly increased and immunofluorescence staining of the DNA damage marker γH2A.X was reduced after clearance of infection compared with cells that had not been infected. Reduced p53 binding to the promoter of the cell cycle checkpoint regulator p21 was also detected in cells cleared of infection and p21 levels were reduced; moreover, this cell population exhibited increased resistance to etoposide-induced DNA damage. Thus, Ctr infection altered cell aging and survival pathways, which persisted after infection clearance. Cells that survive infection are likely to exhibit altered physiology, as evidenced by an increased resistance to DNA damage-induced apoptosis, which may support cellular transformation. 相似文献
957.
958.
959.
目的:探讨胡桃醌通过p38/c-Jun氨基末端激酶(JNK)丝裂原活化蛋白激酶(MAPK)信号通路调控口腔鳞癌Tac8113细胞增殖和凋亡。方法:体外培养口腔鳞癌Tac8113细胞,分别给予终浓度为0,5,10,20μmol·L^-1的胡桃醌,继续培养24 h,检测细胞增殖、细胞凋亡和活性氧(ROS)水平,同时检测Tac8113细胞中p38、p-p38、JNK、p-JNK和Caspase-3蛋白表达水平。结果:与空白对照组比较,给予胡桃醌处理后,Tac8113细胞增殖率降低,Tac8113细胞凋亡率和ROS水平增加(P<0.05),且随着胡桃醌剂量增加,细胞增殖率、凋亡率和ROS变化越显著(P<0.05)。与空白对照组比较,给予胡桃醌处理后,Tac8113细胞p38和JNK蛋白表达变化不显著(P>0.05);p-p38、p-JNK和Caspase-3蛋白表达增加(P<0.05),且随着胡桃醌剂量增加,增加越显著(P<0.05)。结论:胡桃醌可能通过激活p38/JNK MAPK信号通路来诱导Tac8113细胞凋亡,从而达到抑制Tac8113细胞的目的。 相似文献
960.