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51.
Peptide‐Based Fluorescent Probes for Deacetylase and Decrotonylase Activity: Toward a General Platform for Real‐Time Detection of Lysine Deacylation 下载免费PDF全文
Dr. Debra R. Rooker Yuliya Klyubka Dr. Ritika Gautam Prof. Dr. Elisa Tomat Prof. Dr. Daniela Buccella 《Chembiochem : a European journal of chemical biology》2018,19(5):496-504
Histone deacetylases regulate the acetylation levels of numerous proteins and play key roles in physiological processes and disease states. In addition to acetyl groups, deacetylases can remove other acyl modifications on lysines, the roles and regulation of which are far less understood. A peptide‐based fluorescent probe for single‐reagent, real‐time detection of deacetylase activity that can be readily adapted for probing broader lysine deacylation, including decrotonylation, is reported. Following cleavage of the lysine modification, the probe undergoes rapid intramolecular imine formation that results in marked optical changes, thus enabling convenient detection of deacylase activity with good statistical Z′ factors for both absorption and fluorescence modalities. The peptide‐based design offers broader isozyme scope than that of small‐molecule analogues, and is suitable for probing both metal‐ and nicotinamide adenine dinucleotide (NAD+)‐dependent deacetylases. With an effective sirtuin activity assay in hand, it is demonstrated that iron chelation by Sirtinol, a commonly employed sirtuin inhibitor, results in an enhancement in the inhibitory activity of the compound that may affect its performance in vivo. 相似文献
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Isabel Pagani Pietro Demela Silvia Ghezzi Elisa Vicenzi Massimo Pizzato Guido Poli 《International journal of molecular sciences》2022,23(6)
In addition to CD4+ T lymphocytes, myeloid cells and, particularly, differentiated macrophages are targets of human immunodeficiency virus type-1 (HIV-1) infection via the interaction of gp120Env with CD4 and CCR5 or CXCR4. Both T cells and macrophages support virus replication, although with substantial differences. In contrast to activated CD4+ T lymphocytes, HIV-1 replication in macrophages occurs in nondividing cells and it is characterized by the virtual absence of cytopathicity both in vitro and in vivo. These general features should be considered in evaluating the role of cell-associated restriction factors aiming at preventing or curtailing virus replication in macrophages and T cells, particularly in the context of designing strategies to tackle the viral reservoir in infected individuals receiving combination antiretroviral therapy. In this regard, we will here also discuss a model of reversible HIV-1 latency in primary human macrophages and the role of host factors determining the restriction or reactivation of virus replication in these cells. 相似文献
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Filip Alexandrescu Petr Klusáček Stephan Bartke Robert Osman Bohumil Frantál Stanislav Martinát Josef Kunc Lisa Pizzol Alex Zabeo Elisa Giubilato Andrea Critto Alena Bleicher 《Clean Technologies and Environmental Policy》2017,19(5):1323-1334
This article deals with experiences acquired during the process of developing the Timbre Brownfield Prioritization Tool (TBPT). Developing a decision support tool that takes into account the expectations and experiences of its potential users is similar to creating applicable knowledge by the joint action of scientists and heterogeneous actors. Actor network theory is used to explore the construction of this form of applicable knowledge as a process of actor network creation. Following the French sociologist Callon, networks are seen to be initiated and carried out by a group of scientists (tool developers) via four moments of translation, called problematization, interessement, enrolment and mobilization. Each step in the construction of the TBPT—from the initial research question to the final model—can be linked in retrospect to changing configurations of actor networks. Based on the experiences of the tool developers in the Czech Republic, Poland, Germany and Romania, we illustrate how these configurations varied across space and time. This contribution emphasizes the ability to correlate gains in knowledge with the more visible changes in the scope of actor networks in order to highlight achievements but also limitations in acquiring applicable knowledge. 相似文献
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Anna Giovanna Sciancalepore Elisa Mele Valentina Arcadio Francesco Reddavide Francesco Grieco Giuseppe Spano Patrick Lucas Giovanni Mita Dario Pisignano 《Food microbiology》2013
The development of fast, reliable and culture-independent molecular tools to detect bacteria producing biogenic amines deserves the attention of research and ultimately of the food industry in order to protect consumers' health. Here we present the application of a simple, low-cost, fast and sensitive method to perform microdroplet-based multiplex PCR, directly on a food matrix, for the simultaneous detection of bacterial genes involved in biogenic amine biosynthesis. After inoculating wine with Lactobacillus brevis IOEB 9809, cell lysis and DNA amplification are performed in one single step, without preliminary nucleic acid extraction or purification treatments. The assay is performed in about 30 min, requiring 150 nL of starting sample and it enables the detection of down to 15 bacterial cells. With respect to traditional culture techniques, the speed, the simplicity and the cheapness of this procedure allow an effective monitoring of microbial cells during food-making and processing. 相似文献
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Elisa de Almeida Jackix Elisa Bernardes Monteiro Helena Fonseca Raposo Emerielle Cristine Vanzela Jaime Amaya‐Farfán 《Journal of food science》2013,78(12):H1929-H1934
Several studies have shown that fruits and vegetables contribute to protect against degenerative pathologies such as cardiovascular diseases, diabetes, and cancer, mainly due to the presence of dietary fiber (DF) and polyphenols. Taioba (Xanthosoma sagittifolium) is an edible aroid widely grown in many parts of Africa, America, and Asia. The tubers portions of taioba are widely consumed; however, the leafy portions are generally discarded, despite their high nutritive value. In this study, we have partly characterized the DF of lyophiized taioba leaf (LTL), and assessed the possible protective effects on biochemical parameters and on bile acid (BA) production in colon and cecum, when fed to healthy rats for 4 wk. Forty‐five Wistar rats were assigned to either of 5 groups: group 1 received AIN 93G diet (CG: Control); group 2 received AIN 93G containing 2.5% of cellulose + 2.5% inulin (CEIN_5%); group 3 received AIN 93G containing 2.5% of cellulose + 2.5% taioba fiber (CETA_5%); group 4 received AIN 93G containing 5% cellulose + 2.5% taioba fiber (CETA_7.5%); group 5 received AIN 93G containing 5% cellulose + 2.5% of inulin (CEIN_7.5%). LTL showed high contents of total fiber, predominantly comprising insoluble DF with glucose as the major monomer. Rats receiving LTL had increased fecal mass and fat excretion, and improved BA profiles by diminishing the proportion of secondary acids, thus suggesting that consumption of taioba leaf may have the property of lowering the risk of colon cancer. 相似文献
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Objective: Studies examining psychological trauma or posttraumatic stress disorder (PTSD) in ethnoracial or sexual minority groups are relatively few. The Journal of Consulting and Clinical Psychology recently published 4 articles (Balsam, Lehavot, Beadnall, & Circo, 2010; Harrington, Crowther, & Shipherd, 2010; Lester, Resick, Young-Xu, & Artz, 2010; Marshall, Schell, & Miles, 2009) that examine trauma exposure and posttraumatic outcomes in ethnoracial and sexual minority samples. This commentary focuses on the overlap between traumatic stress and diversity studies in order to consider future areas in need of development. Method: Within the framework of a generalized overview of current trends in the study of traumatic stress, an assessment of the strengths and limitations of these 4 articles is provided. Populations and syndromes covered by the articles include ethnoracial differences in child maltreatment and adverse mental health outcomes among sexual minority participants, PTSD symptom elevations among Hispanic Americans, binge eating and the strong Black woman schema, and retention of African American female participants in cognitive behavioral psychotherapy trials for PTSD. Results: Recommendations to enhance culturally competent traumatic stress studies include increasing the examination of within-group cultural variability and key social, contextual, and cultural variables and constructs; examining the temporal sequencing of traumatic events and key transitions in sexual and ethnic minority identity development; and conducting prevention and treatment studies for those sexual minority children most at risk for maltreatment. Conclusions: By following these recommendations, the next generation of studies of traumatic stress studies will be enhanced. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Sobo EJ Billman G Lim L Murdock JW Romero E Donoghue D Roberts W Kurtin PS 《The Joint Commission journal on quality improvement》2002,28(9):498-509
BACKGROUND: The Institute of Medicine's 2001 report on quality delimits six dimensions of optimal care: safety, effectiveness, efficiency, timeliness, patient centeredness, and equity. In fall 2001 parents of pediatric cancer patients were interviewed to determine how well they thought these dimensions were addressed with respect to medication administration. Immediate goals were to identify system weaknesses and devise strategies to prevent future errors. A higher-order goal was to develop and demonstrate a model protocol for rapid-cycle interview assessments. METHODS: Hematology/oncology directors worked with a research expert to develop a semistructured interview protocol. After training, which included directed reading, oral instruction, and role-playing, a convenience sample of 20 English- and Spanish-speaking parents of inpatients was recruited. Parents were asked to characterize current medication administration practices and to describe problems that they had experienced or witnessed. Rapid content analysis techniques were used to identify issues of importance to the parents. FINDINGS: Parents' medication concerns centered on their children's comfort. Parents called for communication improvements, standardization of all nursing procedures and techniques, and a guide or an outline providing a clear understanding of what to expect when and from whom. Viewing these concerns in relation to the Institute of Medicine's quality domains allowed the department to frame an improvement action plan aligned with organizational and national priorities. IMPLICATIONS: With good supervision and limited focused training, inexperienced staff can successfully administer semistructured qualitative interviews and help analyze findings for rapid cycle improvement purposes. The protocol can be adapted for use in organizations interested in rapid qualitative assessments of patient and parent preferences. 相似文献