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How thinking about what could have been affects how we feel about what was
Episodic counterfactual thoughts (CFT) and autobiographical memories (AM) involve the reactivation and recombination of episodic memory components into mental simulations. Upon reactivation, memories become labile and prone to modification. Thus, reactivating AM in the context of mentally generating CFT may provide an opportunity for editing processes to modify the content of the original memory. To examine this idea, this paper reports the results of two studies that investigated the effect of reactivating negative and positive AM in the context of either imagining a better (i.e., upward CFT) or a worse (i.e., downward CFT) alternative to an experienced event, as opposed to attentively retrieving the memory without mental modification (i.e., remembering) or no reactivation. Our results suggest that attentive remembering was the best strategy to both reduce the negative affect associated with negative AM, and to prevent the decay of positive affect associated with positive AM. In addition, reactivating positive, but not negative, AM with or without CFT modification reduces the perceived arousal of the original memory over time. Finally, reactivating negative AM in a downward CFT or an attentive remembering condition increases the perceived detail of the original memory over time
Infection and genotype remodel the entire soybean transcriptome
<p>Abstract</p> <p>Background</p> <p>High throughput methods, such as high density oligonucleotide microarray measurements of mRNA levels, are popular and critical to genome scale analysis and systems biology. However understanding the results of these analyses and in particular understanding the very wide range of levels of transcriptional changes observed is still a significant challenge. Many researchers still use an arbitrary cut off such as two-fold in order to identify changes that may be biologically significant. We have used a very large-scale microarray experiment involving 72 biological replicates to analyze the response of soybean plants to infection by the pathogen <it>Phytophthora sojae </it>and to analyze transcriptional modulation as a result of genotypic variation.</p> <p>Results</p> <p>With the unprecedented level of statistical sensitivity provided by the high degree of replication, we show unambiguously that almost the entire plant genome (97 to 99% of all detectable genes) undergoes transcriptional modulation in response to infection and genetic variation. The majority of the transcriptional differences are less than two-fold in magnitude. We show that low amplitude modulation of gene expression (less than two-fold changes) is highly statistically significant and consistent across biological replicates, even for modulations of less than 20%. Our results are consistent through two different normalization methods and two different statistical analysis procedures.</p> <p>Conclusion</p> <p>Our findings demonstrate that the entire plant genome undergoes transcriptional modulation in response to infection and genetic variation. The pervasive low-magnitude remodeling of the transcriptome may be an integral component of physiological adaptation in soybean, and in all eukaryotes.</p
Simultaneous determination of Deoxynivalenol, Deoxynivalenol-3-Glucoside and Nivalenol in wheat grains by HPLC-PDA with immunoaffinity column cleanup
Deoxynivalenol-3-glucoside (D3G) is a modified mycotoxin formed by the metabolism of plants through the conjugation of deoxynivalenol (DON) with glucose. Toxicology studies of D3G for human and animal health are still under investigation, and the development of practical and reliable methods for its direct determination, especially in cereal matrices, is of great importance. In the present study, a methodology for simultaneous determination of D3G, DON, and nivalenol (NIV) in wheat grains, using immunoaffinity column (IAC) cleanup, separation by C18 column and detection by ultraviolet (UV) absorption, was optimized and in-house validated. The results demonstrated adequate values of D3G recovery from IAC and spiked samples. Intraday precision, linearity, limit of detection and limit of quantification (LOQ) were also adequate for the determination of these mycotoxins. Range of applicability varied from 47.1 to 1000 g/kg for D3G and from 31.3 to 1000 g/kg for DON and NIV, with recovery ranging from 84.7±7.2 % to 112.3±8.1Felipe Trombete is grateful for a doctoral fellowship provided by the Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES)
Rtt107 Phosphorylation Promotes Localisation to DNA Double-Stranded Breaks (DSBs) and Recombinational Repair between Sister Chromatids
Efficient repair of DNA double-stranded breaks (DSB) requires a coordinated response at the site of lesion. Nucleolytic resection commits repair towards homologous recombination, which preferentially occurs between sister chromatids. DSB resection promotes recruitment of the Mec1 checkpoint kinase to the break. Rtt107 is a target of Mec1 and serves as a scaffold during repair. Rtt107 plays an important role during rescue of damaged replication forks, however whether Rtt107 contributes to the repair of DSBs is unknown. Here we show that Rtt107 is recruited to DSBs induced by the HO endonuclease. Rtt107 phosphorylation by Mec1 and its interaction with the Smc5–Smc6 complex are both required for Rtt107 loading to breaks, while Rtt107 regulators Slx4 and Rtt101 are not. We demonstrate that Rtt107 has an effect on the efficiency of sister chromatid recombination (SCR) and propose that its recruitment to DSBs, together with the Smc5–Smc6 complex is important for repair through the SCR pathway
Dramatic Co-Activation of WWOX/WOX1 with CREB and NF-κB in Delayed Loss of Small Dorsal Root Ganglion Neurons upon Sciatic Nerve Transection in Rats
BACKGROUND:Tumor suppressor WOX1 (also named WWOX or FOR) is known to participate in neuronal apoptosis in vivo. Here, we investigated the functional role of WOX1 and transcription factors in the delayed loss of axotomized neurons in dorsal root ganglia (DRG) in rats. METHODOLOGY/PRINCIPAL FINDINGS:Sciatic nerve transection in rats rapidly induced JNK1 activation and upregulation of mRNA and protein expression of WOX1 in the injured DRG neurons in 30 min. Accumulation of p-WOX1, p-JNK1, p-CREB, p-c-Jun, NF-kappaB and ATF3 in the nuclei of injured neurons took place within hours or the first week of injury. At the second month, dramatic nuclear accumulation of WOX1 with CREB (>65% neurons) and NF-kappaB (40-65%) occurred essentially in small DRG neurons, followed by apoptosis at later months. WOX1 physically interacted with CREB most strongly in the nuclei as determined by FRET analysis. Immunoelectron microscopy revealed the complex formation of p-WOX1 with p-CREB and p-c-Jun in vivo. WOX1 blocked the prosurvival CREB-, CRE-, and AP-1-mediated promoter activation in vitro. In contrast, WOX1 enhanced promoter activation governed by c-Jun, Elk-1 and NF-kappaB. WOX1 directly activated NF-kappaB-regulated promoter via its WW domains. Smad4 and p53 were not involved in the delayed loss of small DRG neurons. CONCLUSIONS/SIGNIFICANCE:Rapid activation of JNK1 and WOX1 during the acute phase of injury is critical in determining neuronal survival or death, as both proteins functionally antagonize. In the chronic phase, concurrent activation of WOX1, CREB, and NF-kappaB occurs in small neurons just prior to apoptosis. Likely in vivo interactions are: 1) WOX1 inhibits the neuroprotective CREB, which leads to eventual neuronal death, and 2) WOX1 enhances NF-kappaB promoter activation (which turns to be proapoptotic). Evidently, WOX1 is the potential target for drug intervention in mitigating symptoms associated with neuronal injury
Therapeutic Vaccination With Recombinant Adenovirus Reduces Splenic Parasite Burden in Experimental Visceral Leishmaniasis
Therapeutic vaccines, when used alone or in combination therapy with antileishmanial drugs, may have an important place in the control of a variety of forms of human leishmaniasis. Here, we describe the development of an adenovirus-based vaccine (Ad5-KH) comprising a synthetic haspb gene linked to a kmp11 gene via a viral 2A sequence. In nonvaccinated Leishmania donovani–infected BALB/c mice, HASPB- and KMP11-specific CD8+ T cell responses were undetectable, although IgG1 and IgG2a antibodies were evident. After therapeutic vaccination, antibody responses were boosted, and IFNγ+CD8+ T cell responses, particularly to HASPB, became apparent. A single vaccination with Ad5-KH inhibited splenic parasite growth by ∼66%, a level of efficacy comparable to that observed in early stage testing of clinically approved antileishmanial drugs in this model. These studies indicate the usefulness of adenoviral vectors to deliver leishmanial antigens in a potent and host protective manner to animals with existing L. donovani infection
Optical imaging and spectroscopy for the study of the human brain: status report.
This report is the second part of a comprehensive two-part series aimed at reviewing an extensive and diverse toolkit of novel methods to explore brain health and function. While the first report focused on neurophotonic tools mostly applicable to animal studies, here, we highlight optical spectroscopy and imaging methods relevant to noninvasive human brain studies. We outline current state-of-the-art technologies and software advances, explore the most recent impact of these technologies on neuroscience and clinical applications, identify the areas where innovation is needed, and provide an outlook for the future directions
Dissociation of Motor Task-Induced Cortical Excitability and Pain Perception Changes in Healthy Volunteers
Background: There is evidence that interventions aiming at modulation of the motor cortex activity lead to pain reduction. In order to understand further the role of the motor cortex on pain modulation, we aimed to compare the behavioral (pressure pain threshold) and neurophysiological effects (transcranial magnetic stimulation (TMS) induced cortical excitability) across three different motor tasks. Methodology/Principal Findings Fifteen healthy male subjects were enrolled in this randomized, controlled, blinded, cross-over designed study. Three different tasks were tested including motor learning with and without visual feedback, and simple hand movements. Cortical excitability was assessed using single and paired-pulse TMS measures such as resting motor threshold (RMT), motor-evoked potential (MEP), intracortical facilitation (ICF), short intracortical inhibition (SICI), and cortical silent period (CSP). All tasks showed significant reduction in pain perception represented by an increase in pressure pain threshold compared to the control condition (untrained hand). ANOVA indicated a difference among the three tasks regarding motor cortex excitability change. There was a significant increase in motor cortex excitability (as indexed by MEP increase and CSP shortening) for the simple hand movements. Conclusions/Significance: Although different motor tasks involving motor learning with and without visual feedback and simple hand movements appear to change pain perception similarly, it is likely that the neural mechanisms might not be the same as evidenced by differential effects in motor cortex excitability induced by these tasks. In addition, TMS-indexed motor excitability measures are not likely good markers to index the effects of motor-based tasks on pain perception in healthy subjects as other neural networks besides primary motor cortex might be involved with pain modulation during motor training
Therapeutic targeting of CK2 in acute and chronic leukemias
Phosphorylation can regulate almost every property of a protein and is involved in all fundamental cellular processes. Thus, proper regulation of phosphorylation events is critical to the homeostatic functions of cell signaling. Indeed, deregulation of signaling pathways underlies many human diseases, including cancer.[1] The importance of phosphorylation makes protein kinases and phosphatases promising therapeutic targets for a wide variety of disorders.[2] CK2, formerly known as casein kinase II, was discovered in 1954, [3] although only recently, and especially over the last two decades, it has become one of the most studied protein kinases, due to its ubiquity, pleiotropy and constitutive activity. In particular, appreciation of its pleiotropy has completely changed our vision of CK2 biology, from an ordinary cell homeostasis-maintaining enzyme to a master kinase potentially implicated in many human physiological and pathological events. CK2 is responsible for about 25% of the phosphoproteome,[4] as it catalyzes the phosphorylation of >300 substrates.[5] This partly explains the CK2 interconnected roles that underlie its involvement in many signaling pathways. However, CK2 prevalent roles are promotion of cell growth and suppression of apoptosis. Accordingly, several lines of evidence support the notion that CK2 is a key player in the pathogenesis of cancer. High levels of CK2 transcript and protein expression, as well as increased kinase activity are associated with the pathological functions of CK2 in a number of neoplasias.[6] It was only over the last decade, after extensive analyses in solid tumors, that basic and translational studies have provided evidence for a pivotal role of CK2 in driving the growth of different blood cancers as well, although the first report demonstrating increased CK2 expression in acute myelogenous leukemia (AML) dates back to 1985.[7] Since then, CK2 overexpression/activity has been demonstrated in other hematological malignancies, including acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL) and chronic myelogenous leukemia (CML). [8] With the notable exceptions of CML and pediatric ALL, many patients with leukemias still have a poor outcome, despite the development of protocols with optimized chemotherapy combinations. Insufficient response to first-line therapy and unsalvageable relapses present major therapeutic challenges. Moreover, chemotherapy, even if successful, could have deleterious long-term biological and psychological effects, especially in children.[9] Furthermore, CML patients can develop resistance to tyrosine kinase inhibitors (TKIs), while both primary chemoresistant and relapsed pediatric ALL cases still remain an unresolved issue.[9
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