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Identification and characterization of SNO regulated genes (SRGs) in plant immunityCui, Beimi January 2015 (has links)
A conspicuous feature of plants responding to pathogen invasion is the synthesis of nitric oxide (NO), a redox signal. NO regulates protein function by S-nitrosylation, the addition of an NO moiety to a cysteine thiol to form an S-nitrosothiol. A key theme of NO function is reprogramming plant immune-related gene expression. However, it is still not clear how the NO signal is translated into transcriptional changes. Here we explored the potential role of a sub-group of SNO Regulated Genes (SRGs) uncovered by global expression profiling. Firstly, transgenic plants containing the SRG1 or SRG3 promoter fused to glucuronidase gene GUS together with qRT-PCR assays confirmed that transcripts of SRGs could be induced by NO and pathogen challenge, suggesting that SRGs may be involved in NO signalling related to plant immunity. More importantly, transient and stable overexpression of SRG genes induced hypersensitive response (HR)-like cell death development, which is often associated with pathogen effector-triggered immunity. Furthermore, transgenic plants constitutively expressing SRG genes exhibited enhanced ROS accumulation, PR1 transcript accumulation, and increased resistance to Pseudomonas syringae (Pst) DC3000 compared with Col-0 wild type plants. In contrast, lines with T-DNA insertions into SRG genes exhibited susceptibility to Pst DC3000. These data suggested SRGs act as the positive regulators in plant immunity. In order to further explore how NO regulates these SRGs in plant immunity, we focused on SRG1 and found SRG1 could be S-nitrosylated in vitro and in vivo. Moreover, electrophoretic mobility shift assays showed SRG1 could bind to an AGT motif and the transcriptional activity was blunted in the presence of NO, suggesting that the DNA binding activity of SRG1 is redox-modulated. Further, a transient repression activity assay showed that SRG1 has repression activity and this activity was impaired in the gsnor1-3 mutant, which has a high S-nitrosothiols level. These data suggested NO could block SRG1 transcriptional activity in vitro and in vivo. Furthermore when the SRG1 overexpression line was crossed with gsnor1-3 the SRG1-mediated resistance related phenotypes were suppressed. These data demonstrated NO negatively regulates SRG1 transcriptional activity during plant immunity. SRG1 may therefore be an important regulator of NO signalling and subsequent regulate transcription during plant immunity. Additionally, NO may negatively feedback to inhibit transcriptional activity of SRG1 to control its repression activity, to enable the activation of plant immunity.
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Computational characterization of IRE-regulated genes in Glossina morsitansDashti, Zahra Jalali Sefid January 2013 (has links)
Philosophiae Doctor - PhD / Blood feeding is a habit exhibited by many insects. Considering the devastating impact
of these insects on human health, it is important to focus research on understanding the
biology behind blood-feeding, disease transmission and host-pathogen interactions. Such knowledge would pave the way for developing efficient preventative measures.
Iron an important element for species survival, is at the center of events controlling tsetse’s fitness and reproductive success. Hence, targeting genes involved in iron trafficking and sequestration would present possible means of preventing disease transmission. Considering the dynamic and multi-factorial nature of iron metabolism, a well-coordinated regulatory system is expected to be at work. Despite extensive literature on the mechanism of iron regulation and key factors responsible in maintaining its homeostasis in human, less attention has been given to understand such system in insects, especially the blood-feeding insects. The availability of the genome sequences for several insect disease vectors allows for a more detailed analysis on the identification and characterization of events controlling and preventing iron-induced toxicity following a blood-meal. The International Glossina Genome Initiative (IGGI) has coordinated the sequencing and annotation of the Glossina morsitans genome that has led to the identification of 12220 genes. This knowledge-base along with current understanding of the IRE system in regulating iron metabolism, allowed for investigating the UTRs of Glossina genes for the presence of these elements. Using a combination of motif enrichment and IRE-stem loop structure prediction, an
IRE-mediated regulation was inferred for 150 genes, among which, 72 were identified
with 5’-IREs and 78 with 3’-IREs. Of the identified IRE-regulated genes, the ferritin
heavy chain and MRCK-alpha are the only known genes to have IREs, while the rest
are novel genes for which putative roles in regulating iron levels in tsetse fly have been
assigned in this study. Moreover, the functional inference of the identified genes further
points to the enrichment of transcription and translation. Furthermore, several hypothetical proteins with no defined functions were identified to be IRE-regulated. These include TMP007137, TMP009128, TMP002546, TMP002921, TMP003628, TMP004581, TMP008259, TMP012389, TMP005219, TMP005827, TMP007908, TMP009332, TMP01- 3384, TMP009102, TMP010544, TMP010707, TMP004292, TMP006517, TMP014030, TMP009821 and TMP003060 for which an iron-regulatory mechanism of action may be inferred. We further report 26 IRE-regulated secreted proteins in Glossina, that present good candidates for further investigation pertaining to the development of novel vector control strategies. Using the predicted data on the identified IRE-regulated genes and their functional classification, we derived at 29 genes with putative roles in iron trafficking, where several unknown and hypothetical proteins are included. Thus a novel role is inferred for these genes in cellular binding and transport in the context of iron metabolism. It is therefore possible that these genes may have evolved in Glossina, such that they compensate for the absence of an IRE- regulated mechanism for transferrin. Additionally, we propose 14 IRE-regulated genes involved in immune and stress response, which may indeed play crucial roles at the host pathogen interface through their possible mechanisms of iron sequestration.
Using the subcellular localization analysis, we further categorized the putative IRE regulated genes into several subcellular localizations, where the majority of genes were
found within the nucleus and the cytosol. The detection of the conserved motifs in a set of genes, is an interesting yet sophisticated area of research, that allows for identifying either co-regulated or orthologous genes, while further providing support for the putative function of a set of genes that would otherwise remain uncharacterized. This is based on the notion that co-regulated genes are often coexpressed to carry out a specific function. As such, 14 regulatory elements were identified in the 5’- and 3’-UTRs of IRE-regulated genes, involved in embryonic development and reproduction, inflammation and immune response, signaling pathways and neurogenesis
as well as DNA repair. This study further proposes several IRE-regulated genes as targets for micro-RNA regulation through identifying micro-RNA binding sites in their 3’UTRs. Using a motif clustering approach we clustered IRE-regulated genes based on the number of motifs they share. Significantly co-regulated genes sharing two or more motifs were determined as critical targets for future investigation. The expression map of IRE-regulated genes was analyzed to better understand the events taking place from 3 hours to 15 days following a blood meal. Re-analysis of Anopheles microarray chip showed the significant expression of three cell envelope and transport genes as early response and six as late response to a blood meal, which could indeed be assigned a putative role in iron trafficking. Genes identified in this study with implications
in iron metabolism, whose timely expression allows for maintaining iron homeostasis,
represent good targets for future work. Considering the important role of evolution in species adaptation to habits such as Hematophagy, it is of importance to identify evolutionary signatures associated with these changes. To distinguish between evolutionary forces that are specific to iron-metabolism in blood-feeding insects and those that are found in other insects, the IRE-regulated genes were clustered into orthologous groups using several blood feeding and non-blood feeding insect species. Assessment of different evolutionary scenarios using the Maximum Likelihood
(ML) approach, points to variations in the evolution of IRE-regulated genes between the two insect groups, whereby several genes indicate an increased mutation rate in the
BF-insect group relative to their non-blood feeding insect counterparts. These include
TMP003602 (phosphoinositide3-kinase), TMP009157 (ubiquitin-conjugating enzyme9),
TMP010317 (general transcription factor IIH subunit1), TMP011104 (serine-pyruvate mitochondrial), TMP013137 (pentatricopeptide Transcription and translation), TMP013886 (tRNA(uridine-2-o-)-methyl-transferase-trm7) and TMP014187 (mediator 100kD).
Additionally, we have indicated the presence of positively selected sites within seven
blood-feeding IRE-regulated genes namely TMP002520 (nucleoporin), TMP008942 (eukaryotic translation initiation factor 3), TMP009871(bruno-3 transcript) , TMP010317
(general transcription factor IIH subunit1), TMP010673 (ferritin heavy-chain protein),
TMP011104 (serine-pyruvate mitochondrial) and TMP011448 (brain chitinase and chia).
Thus the results of this study provides an in depth understanding of iron metabolism in
Glossina morsitans and confers important targets for future validations based on which
innovative control strategies may be designed.
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L'ostéopathie, quel chemin vers une profession de santé ? / Osteopathy, which way to a health profession ?Dahdouh, Fadi 09 January 2015 (has links)
L’ostéopathie, depuis la loi du 4 mars 2002, n’est plus considérée comme un exercice illégal de la médecine. Néanmoins, le législateur a créé avec les décrets de 2007 un titre partagé entre des médecins et des non-médecins, sans créer une profession de santé. Sa nature controversée et son régime ambigu rendent l’ostéopathie en position inédite dans le paysage sanitaire français. Les textes définissent un titre, et non une profession ; les recommandations de l’organisation mondiale de la santé encouragent vers une reconnaissance d’une médecine complémentaire et l’Europe incite via ses directives à reconnaître une profession réglementée. En France, la règle est souvent née de la pratique et la réalité du terrain doit être confrontée à la règle. Sans oublier que le patient doit rester avant tout le moteur, l’axe principal ainsi que le repère qui doit animer les juristes, les professionnels et les législateurs. / Osteopathy is no longer considered as an illegal practice of medicine after the Act of the 4th of March 2002. However, following the 2007 decrees, the legislature created a shared title be-tween physicians and non-physician, without creating a health profession. Its controversial nature and its ambiguous regime have put the osteopathy in unique position in the French health landscape. The texts define a title, not a profession. The recommendations of the World Health Organization encourage the recognition of complementary medicine and Europe via its guidelines incites to recognize a pro-regulated profession. In France, the rule is often born of practice and the reality must be faced by the rule. Without forgetting the fact that the patient must remain primarily the engine, the main axis and the benchmark that should animate law-yers, professionals and legislators.
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Analysis of Actors and Discourse in the Amendment of Ontario’s Regulated Health Professions Act, 1991, to Support Interprofessional CollaborationKapral, Olena January 2013 (has links)
Identifying how policy proposals are selected by policy-makers is an important question for scholars. This thesis evaluates the use of discourse and the role of actors in the exchange of ideas to support interprofessional collaboration (IPC) among Ontario’s regulatory colleges. A variation of discourse analysis was developed, based on the seven areas of reality that are constructed by language, to evaluate the interactions between state and policy actors. I argue that actors did not appear to engage in meaningful discourse because the state established the parameters of the consultative processes, which suggests the expert consultative processes were tools to legitimize the policy process for Bill 179. The state appears to have increasingly greater control of both the content and context of policy- making in this field. Further evaluation of the interactions between health professional organizations and the state is needed to better understand the importance of discourse in the health policy process.
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Optimizing mental health for student success at university: a case for self-regulated learningDavis, Sarah K. 04 January 2021 (has links)
Mental health is one of the biggest issues facing governments around the globe (Keyes, 2013). Mental health is a state of well-being wherein individuals realize their potential, cope with normal life stressors, work productively, and contribute to society (World Health Organization, 2014). Findings from the American College Health Assessment survey reveal the vast majority of postsecondary students in Canada and the United States report (a) feeling inundated and exhausted by their academic work, and (b) experiencing levels of stress and anxiety compromising physical and mental health, academic learning, and personal success (ACHA, 2019). Self-regulated learning (SRL) is a key component of student success at university, however despite the large body of research establishing the role of SRL in student success at university, there is a paucity of research on mental health and SRL at university. To date mental health and SRL have been underexamined as dynamic processes that develop over time as highly situated, metacognitive processes. The purpose of this multi-paper dissertation was twofold: (a) to examine the interplay between self-regulated learning and mental health in student success at university, and (b) to explore a variety of methods and analyses examining this interplay. Davis and Hadwin (2019) examined psychological well-being (PWB) and SRL and how they differ between groups of students with different levels of within-person PWB during an academic semester of a learning-to-learn course. Davis, Milford, and MacDonald (2019) used multi-level modelling to further examine the associations over time between students’ PWB and academic engagement, goal attainment, goal satisfaction, and rating of mental health and well-being challenge. Finally, Davis, Rostampour, Hadwin, and Rush (2020) built on the findings of Papers 1 and 2 by using a case study approach to examine mental health and adaptive regulation exhibited by two contrasting groups of students (i.e., the high mental health group and the low mental health group) in a university learning-to-learn course. There were five main findings from the studies in this dissertation. First, there is a positive relation between PWB and SRL. Second, mental health is a condition and product affecting learning. Third, students’ mental health affects metacognitive standards and is a target of learning goals. Fourth, students’ mental health affects their engagement in adaptive regulation of learning. Fifth, including mental health in online SRL diary tools may benefit all students. Finally, the main findings from this dissertation provide two directions for future research: (a) considering the interplay of mental health SRL as a heuristic process fueled by metacognition where students take an active role, experiment, and consider feedback in their learning, and (b) situating mental health within metacognitive SRL interventions. / Graduate
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Exploring the Impact on Self-regulated Learning: a Comparative Analysis of Learner Experiences Using Problem-based Learning, Game Play, and Computer-based InstructionNajmi, Anjum A. 08 1900 (has links)
The ability to transfer what you know to new and different contexts is a sign of successful learning. While students often graduate from college with the required number of courses many lack the skills necessary to apply appropriate strategies to solve problems in different contexts, to reason, and think critically. More than a decade ago the Boyer Report (1995) pointed to this fact as a sign that Universities were falling short in adequately supporting their undergraduate populations. As a result, it is not uncommon to see educational institutions introducing new courses and programs geared towards helping students learn better. This study explores learner experiences and the impact on self-regulated learning within a distributed learning setting when motivated by problem-based learning, game play, and computer-based instruction. In this study the instructional design of the course introduced undergraduate students to authentic learning experiences in which students engaged in collaborative problem solving and learning activities framed within the narrative of an alternate reality game. Fifteen self-regulated learning constructs were examined. The comparison group engaged with problem solving tasks and computer-based instruction. Additionally, the study used the theory Learning and Teaching as Communicative Action and its four communicative actions as a lens to understand the full range of student interactions and how they constructed knowledge. The research design employed computer-mediated discourse analysis to examine qualitative data. Data was triangulated through constant-comparative coding of student communication in the form of web logs, emails, student assignments, and semi-structured interviews. Review and consensus building was embedded in the process of identifying emerging codes and categories, and used to support emergent inferences before the final themes were identified and mutually agreed upon. Finally, to evaluate the outcome of the instructional design, pre and posttest measures were used among groups using a two-sample t-test. Statistical significance was used to determine changes in learning outcomes while select qualitative codes were examined and reviewed to gauge student satisfaction with the instructional approach. Results indicated substantial qualitative and quantitative differences among the three versions of the course related to self-regulated learning practices and communicative action in particular in terms of student interaction, and knowledge construction. Additional, findings revealed differences in epistemic beliefs about learning, which in turn influenced how students chose to learn. These outcomes are presented and discussed along with the implications for instructional design.
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Self-regulated Learning Characteristics of Successful Versus Unsuccessful Online Learners in ThailandSamruayruen, Buncha 05 1900 (has links)
The purpose of this study was to identify the existing level of self-regulated learning (SRL) among Thai online learners, to examine the relationship between SRL and academic achievement based on a) course completion and b) course grades, and to investigate differences in SRL as they correlate to demographic factors. A mixed-methods research design with modified MSLQ online surveys and semi-structured interviews was used during the process of data collection. One hundred eighty-eight of the 580 online learners enrolled in the certificate programs of the Thailand Cyber University Project responded to the surveys; 7 of these also participated in the interview process. The findings indicated that Thai online learners reported high levels of SRL characteristics. Independent sample t-test results revealed that successful learners were higher in SRL learning strategies than those who did not succeed the course. Results from multiple regression analyses indicated that critical thinking and time/study environmental management were significant predictors of academic course grade with a small effect size (R2 = .113). Comparison of mean differences revealed that some SRL characteristics were different among demographic subgroups determined by factors including gender, age range, marital status, and Internet use; female reported a significantly higher level of task value than male; younger learners had a significantly higher level of test anxiety than older learners; married learners reported a significantly higher level of self-efficacy and task value than single learners; online learners who had more Internet experience reported a significantly higher level of self-efficacy, metacognitive self-regulation, and time/study environmental management than those who had less Internet experience. In addition, the qualitative findings confirmed that participants reported the use of learning strategies in four categories, with a high number of references to metacognitive self-regulation and elaboration, and a low number of references to critical thinking and time/study environmental management. Furthermore, the qualitative results revealed that Thai online learners used different tools for social and personal activities, communication, and information searching.
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Factors Released From Embryonic Stem Cells Inhibit Apoptosis in h9c2 Cells Through PI3K/Akt but Not ERK PathwaySingla, Dinender, Singla, Reetu D., McDonald, Debbie E. 01 August 2008 (has links)
We recently reported that embryonic stem cells-conditioned medium (ES-CM) contains antiapoptotic factors that inhibit apoptosis in the cardiac myoblast H9c2 cells. However, the mechanisms of inhibited apoptosis remain elusive. In this report, we provide evidence for the novel mechanisms involved in the inhibition of apoptosis provided by ES-CM. ES-CM from mouse ES cells was generated. Apoptosis was induced after exposure with H2O2 (400 μm) in H9c2 cells followed by the replacement with ES-CM or culture medium. H9c2 cells treated with H2O2 were exposed to ES-CM, and ES-CM plus cell survival protein phosphatidylinositol 3-kinase/Akt inhibitor, LY-294002, or extracellular signal-regulated kinase (ERK1/2) inhibitor, PD-98050. After 24 h, H9c2 cells treated with ES-CM demonstrated a significant increase in cell survival. ES-CM significantly inhibited (P < 0.05) apoptosis determined by terminal deoxynucleotidyl transferase dUTP-mediated nickend labeling staining, apoptotic ELISA, and caspase-3 activity. Importantly, enhanced cell survival and inhibited apoptosis with ES-CM was abolished with LY-294002. In contrast, PD-98050 shows no effect on ES-CM-increased cell survival. Furthermore, H2O2-induced apoptosis is associated with decreased levels of phosphorylated (p)Akt activity. Following treatment with ES-CM, we observed a decrease in apoptosis with an increase in pAkt, and the increased activity was attenuated with the Akt inhibitor, suggesting that the Akt pathway is involved in the decreased apoptosis and cell survival provided by ES-CM. In contrast, we observed no change in ES-CM-decreased apoptosis or pERK with PD-98050. In conclusion, we suggest that ES-CM inhibited apoptosis and is mediated by Akt but not the ERK pathway.
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Self-Regulated learning and academic performance among pupils at Qhakaza High School in Kwa-Zulu Natal Province, South Africa.Ngcobo, Sinethemba January 2018 (has links)
A dissertation submitted to the Faculty Of Arts in fulfillment of the requirements for the Degree of Masters in the Department of Sociology at the University Of Zululand, 2018 / In spite of numerous initiatives, resources and infrastructural provision, the continuous decline in Learners’ academic performance remains a global phenomenon that threatens economic development. Scholars have therefore been interested in unravelling factors that enhance or impede academic performance. Self-regulated learning (SRL) refers to a self-initiated and directed learning process; this agentic angle of the social cognitive theory introduces human agency as a solution to students declining academic performance. Self-regulated learning encompasses motivation, self-judgement, self-efficacy, cognition and assessment feedback. Current literature on self-regulated learning and academic performance is limited to subject specific investigations, which seek to determine suitable learning strategies for specific learning areas. The present study investigated the relationship between components of self-regulated learning and academic performance. The purpose of the study was to determine whether self-regulated learning could improve, the academic performance of high school students. Learners’ perceived levels of motivation, self-judgement, self-efficacy, cognition, assessment feedback and their self-reported academic performance were collated using a self-report questionnaire. Motivation, self-judgement, self-efficacy, cognition and assessment feedback are components of SRL. Each variable provides a skill or strategy that is linked to academic success. In a survey, (n=101), data was collected using the Likert scale type self-report questionnaires from grade 10 learners at Qhakaza High School, KwaDlangezwa, in the Kwa-Zulu Natal Province of South Africa. In the first order of analysis, responses were reduced using Principal Components Analysis (PCA), to determine how questionnaire items contributed to the variables of interest. Furthermore, bivariate correlations and hierarchical stepwise linear regressions were carried out to establish simple relationships between the dependent and independent variables. The results showed that cognition and assessment feedback were the only two variables of self-regulated learning which were positively related to Learners’ academic performance. The result thus indicated, contrary to many past, studies that the perceived level of motivation, perceived level of self-judgement and perceived level of self-efficacy were statistically insignificant as predictors of Learners’ academic performance. The results of this study thus showed that cognition and assessment feedback are learning strategies that should be fostered towards improving Learners’ academic performance in high schools. Cognition and assessment feedback are two variables, which are mostly facilitated or provided by teachers. This implies that contrary to the propositions of the SRL’s agentic component, Learners’ responsibilities for their own learning outcomes may not be relevant in the sample of this study as none of the self-directed variables of perceived level of motivation, perceived level of self-judgement and perceived level of self-efficacy were correlated to academic performance. The main conclusion of the study was that not all components of self-regulated learning influence academic performance. It was therefore recommended that the teacher-learner approach should be revised to suit the contemporary classroom environments, since students still struggle with self-directed learning. / Prestige Bursary
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Maximizing Feedback for Self-Regulated LearningHemerda, Jodie Maria 01 January 2016 (has links)
Application of clearly defined feedback types, which have been correlated with improved student performance, has great potential for maximizing instructor use of feedback and its effect on a learner's self-regulatory learning (SRL) for optimized learning. Within SRL, where learner performance is influenced by a recursive internal process, instructional feedback plays a critical role. Yet, the characteristics of external feedback that influence SRL to improve performance are unclear in the literature. Within a theoretical framework where feedback catalyzes self-regulation, this quantitative study sought to integrate feedback type research to expand the SRL model. Data were graded assignments from 23 undergraduate level and 8 graduate level online university courses randomly selected from a pool of 86 possible courses. Applying non-experimental logistic regression and using descriptive statistics, feedback was categorized to determine the quantity of each of the 5 feedback types [task correctness (FC), task elaboration (TE), task process (FP), self-regulation (FR), and personal or self-related (FS)], as well as how they correlated with improved performance. The results indicate that the feedback types were not normally distributed, FS was statistically not present and FE was most used, and the logistical regression indicated that the presence of FC and FR was minimally associated with improved performance. Additional experimentation is needed to normalize the type distribution and test the strength of the FC and FR effect. This study initiated a clarification in understanding the external component of feedback in the SRL model, which is necessary to harness feedback to create positive change in the self-regulatory processes of learners.
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