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51.
Ahn Woo-Young; Rass Olga; Fridberg Daniel J.; Bishara Anthony J.; Forsyth Jennifer K.; Breier Alan; Busemeyer Jerome R.; Hetrick William P.; Bolbecker Amanda R.; O'Donnell Brian F. 《Canadian Metallurgical Quarterly》2011,120(4):911
Patients with bipolar disorder (BD) and schizophrenia (SZ) often show decision-making deficits in everyday circumstances. A failure to appropriately weigh immediate versus future consequences of choices may contribute to these deficits. We used the delay discounting task in individuals with BD or SZ to investigate their temporal decision making. Twenty-two individuals with BD, 21 individuals with SZ, and 30 healthy individuals completed the delay discounting task along with neuropsychological measures of working memory and cognitive function. Both BD and SZ groups discounted delayed rewards more steeply than did the healthy group even after controlling for current substance use, age, gender, and employment. Hierarchical multiple regression analyses showed that discounting rate was associated with both diagnostic group and working memory or intelligence scores. In each group, working memory or intelligence scores negatively correlated with discounting rate. The results suggest that (a) both BD and SZ groups value smaller, immediate rewards more than larger, delayed rewards compared with the healthy group and (b) working memory or intelligence is related to temporal decision making in individuals with BD or SZ as well as in healthy individuals. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
52.
Evgeniya S. Grigoryeva Liubov A. Tashireva Vladimir V. Alifanov Olga E. Savelieva Sergey V. Vtorushin Marina V. Zavyalova Nadezhda V. Cherdyntseva Vladimir M. Perelmuter 《International journal of molecular sciences》2022,23(16)
Stemness and epithelial–mesenchymal plasticity are widely studied in the circulating tumor cells of breast cancer patients because the roles of both processes in tumor progression are well established. An important property that should be taken into account is the ability of CTCs to disseminate, particularly the viability and apoptotic states of circulating tumor cells (CTCs). Recent data demonstrate that apoptosis reversal promotes the formation of stem-like tumor cells with pronounced potential for dissemination. Our study focused on the association between different apoptotic states of CTCs with short- and long-term treatment outcomes. We evaluated the association of viable CTCs, CTCs with early features of apoptosis, and end-stage apoptosis/necrosis CTCs with clinicopathological parameters of breast cancer patients. We found that the proportion of circulating tumor cells with features of early apoptosis is a perspective prognosticator of metastasis-free survival, which also correlates with the neoadjuvant chemotherapy response in breast cancer patients. Moreover, we establish that apoptotic CTCs are associated with the poor response to neoadjuvant chemotherapy, and metastasis-free survival expressed at least two stemness markers, CD44 and CD133. 相似文献
53.
Anastasiya Mamaeva Olga Krasnova Irina Khvorova Konstantin Kozlov Vitaly Gursky Maria Samsonova Olga Tikhonova Irina Neganova 《International journal of molecular sciences》2023,24(1)
Human pluripotent stem cells are promising for a wide range of research and therapeutic purposes. Their maintenance in culture requires the deep control of their pluripotent and clonal status. A non-invasive method for such control involves day-to-day observation of the morphological changes, along with imaging colonies, with the subsequent automatic assessment of colony phenotype using image analysis by machine learning methods. We developed a classifier using a convolutional neural network and applied it to discriminate between images of human embryonic stem cell (hESC) colonies with “good” and “bad” morphological phenotypes associated with a high and low potential for pluripotency and clonality maintenance, respectively. The training dataset included the phase-contrast images of hESC line H9, in which the morphological phenotype of each colony was assessed through visual analysis. The classifier showed a high level of accuracy (89%) in phenotype prediction. By training the classifier on cropped images of various sizes, we showed that the spatial scale of ~144 μm was the most informative in terms of classification quality, which was an intermediate size between the characteristic diameters of a single cell (~15 μm) and the entire colony (~540 μm). We additionally performed a proteomic analysis of several H9 cell samples used in the computational analysis and showed that cells of different phenotypes differentiated at the molecular level. Our results indicated that the proposed approach could be used as an effective method of non-invasive automated analysis to identify undesirable developmental anomalies during the propagation of pluripotent stem cells. 相似文献
54.
Konstantin B. Shumaev Olga V. Kosmachevskaya Elvira I. Nasybullina Enno K. Ruuge Alexey F. Topunov 《International journal of molecular sciences》2023,24(1)
Carbonyl stress occurs when reactive carbonyl compounds (RCC), such as reducing sugars, dicarbonyls etc., accumulate in the organism. The interaction of RCC carbonyl groups with amino groups of molecules is called the Maillard reaction. One of the most active RCCs is α-dicarbonyl methylglyoxal (MG) that modifies biomolecules forming non-enzymatic glycation products. Organic free radicals are formed in the reaction between MG and lysine or Nα-acetyllysine. S-nitrosothiols and nitric oxide (•NO) donor PAPA NONOate increased the yield of organic free radical intermediates, while other •NO-derived metabolites, namely, nitroxyl anion and dinitrosyl iron complexes (DNICs) decreased it. At the late stages of the Maillard reaction, S-nitrosoglutathione (GSNO) also inhibited the formation of glycation end products (AGEs). The formation of a new type of DNICs, bound with Maillard reaction products, was found. The results obtained were used to explain the glycation features of legume hemoglobin—leghemoglobin (Lb), which is a lysine-rich protein. In Lb, lysine residues can form fluorescent cross-linked AGEs, and •NO-derived metabolites slow down their formation. The knowledge of these processes can be used to increase the stability of Lb. It can help in better understanding the impact of stress factors on legume plants and contribute to the production of recombinant Lb for biotechnology. 相似文献
55.
Luciano J. Quitão-Teixeira Ingrid Aguiló-Aguayo Afonso M. Ramos Olga Martín-Belloso 《Food and Bioprocess Technology》2008,1(4):364-373
The effects of high-intensity pulsed electric fields (HIPEF) on oxidative enzymes and color of fresh carrot juice were studied.
A response surface methodology (RSM) was used to evaluate the effect of pulse polarity (mono or bipolar mode), pulse width
(from 1 to 7 μs), and pulse frequency (from 50 to 250 Hz) on color and peroxidase (POD) inactivation of carrot juice treated
by HIPEF. The total treatment time and the electric field strength were set at 1,000 μs and 35 kV/cm, respectively, at a temperature
below 35°C. The physicochemical characteristics of carrot juice were measured. There was a linear relationship between electrical
conductivity and temperature of the carrot juice. The results showed that HIPEF-treated carrot juice at 35 kV/cm for 1,000 μs
applying 6 μs pulse width at 200 Hz in bipolar mode led to 73.0% inactivation of POD. The color coordinates did not change
significantly. Therefore, HIPEF was effective in POD inactivation and carrot juice color preservation. 相似文献
56.
Comprehensive Review of Patulin Control Methods in Foods 总被引:1,自引:0,他引:1
Matthew M. Moake Olga I. Padilla‐Zakour Randy W. Worobo 《Comprehensive Reviews in Food Science and Food Safety》2005,4(1):8-21
The mycotoxin, patulin (4‐hydroxy‐4H‐furo [3, 2c] pyran‐2[6H]‐one), is produced by a number of fungi common to fruit‐ and vegetable‐based products, most notably apples. Despite patulin's original discovery as an antibiotic, it has come under heavy scrutiny for its potential negative health effects. Studies investigating these health effects have proved inconclusive, but there is little doubt as to the potential danger inherent in the contamination of food products by patulin. The danger posed by patulin necessitates its control and removal from foods products, creating a demand for handling and processing techniques capable of doing so, preferably at low cost to industry. With this being the case, much research has been devoted to understanding the basic chemical and biological nature of patulin, as well as its interaction within foods and food production. While past resarch has elucidated a great deal, patulin contamination continues to be a challenge for athe food industry. Here, we review in depth the past research on patulin with an emphasis upon its influence within the food industry, including its regulation, health effects, biosynthesis, detection, quantification, distribution within foods, and control, during the various stages of apple juice production. Finally, key areas where future patulin research should focus to best control the patulin contamination problem within the food industry are addressed. 相似文献
57.
Phenol‐enriched olive oils modify paraoxonase‐related variables: A randomized,crossover, controlled trial 下载免费PDF全文
58.
众多植物多糖中,阿拉伯半乳聚糖对嗜黏蛋白阿克曼菌(Akkermansia muciniphila,Akk)模式菌株(DSM 22959)的促生长效果最佳.为进一步探究阿拉伯半乳聚糖对Akk代谢物的影响,本研究将阿拉伯半乳聚糖作为部分碳源对Akk进行体外发酵培养,确定了阿拉伯半乳聚糖的补充量以便于Akk发酵液样本的后续分... 相似文献
59.
Aleksandra A. Kuznetsova Olga S. Fedorova Nikita A. Kuznetsov 《International journal of molecular sciences》2022,23(12)
DNA polymerases catalyze DNA synthesis during the replication, repair, and recombination of DNA. Based on phylogenetic analysis and primary protein sequences, DNA polymerases have been categorized into seven families: A, B, C, D, X, Y, and RT. This review presents generalized data on the catalytic mechanism of action of DNA polymerases. The structural features of different DNA polymerase families are described in detail. The discussion highlights the kinetics and conformational dynamics of DNA polymerases from all known polymerase families during DNA synthesis. 相似文献
60.