929 resultados para transcript
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Xylella fastidiosa is the etiologic agent of a wide range of plant diseases, including citrus variegated chlorosis (CVC), a major threat to citrus industry. The genomes of several strains of this phytopathogen were completely sequenced, enabling large-scale functional studies. DNA microarrays representing 2,608 (91.6%) coding sequences (CDS) of X. fastidiosa CVC strain 9a5c were used to investigate transcript levels during growth with different iron availabilities. When treated with the iron chelator 2,2`-dipyridyl, 193 CDS were considered up-regulated and 216 were considered down-regulated. Upon incubation with 100 mu M ferric pyrophosphate, 218 and 256 CDS were considered up- and down-regulated, respectively. Differential expression for a subset of 44 CDS was further evaluated by reverse transcription-quantitative PCR. Several CDS involved with regulatory functions, pathogenicity, and cell structure were modulated under both conditions assayed, suggesting that major changes in cell architecture and metabolism occur when X. fastidiosa cells are exposed to extreme variations in iron concentration. Interestingly, the modulated CDS include those related to colicin V-like bacteriocin synthesis and secretion and to functions of pili/fimbriae. We also investigated the contribution of the ferric uptake regulator Fur to the iron stimulon of X. fastidiosa. The promoter regions of the strain 9a5c genome were screened for putative Fur boxes, and candidates were analyzed by electrophoretic mobility shift assays. Taken together, our data support the hypothesis that Fur is not solely responsible for the modulation of the iron stimulon of X fastidiosa, and they present novel evidence for iron regulation of pathogenicity determinants.
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HSP90 proteins are important molecular chaperones involved in multiple cellular processes. This work reports the characterization of cDNAs encoding two distinct HSP90 proteins (named HSP90A and HSP90B) from the chytridiomycete Blastocladiella emersonii. Deduced amino acid sequences of HSP90A and HSP90B exhibit signatures of the cytosolic and endoplasmic reticulum (ER) HSP90 proteins, respectively. A genomic clone encoding HSP90A was also characterized indicating the presence of a single intron of 184 bp interrupting the coding region, located near the amino-terminus of the protein. Expression of both HSP90A and HSP90B genes increases significantly during heat shock at 38 degrees C, with highest induction ratios observed in cells stressed during germination of the fungus. Changes in the amount of HSP90A transcript were also evaluated during B. emersonii life cycle at physiological temperature (27 degrees C), and its levels were found to increase both during germination and sporulation of the fungus. HSP90A protein levels were analyzed during B. emersonii life cycle and significant changes were observed only during sporulation. Furthermore, during heat stress a large increase in the amount of HSP90A protein was observed. Induction of HSP90A and HSP90B genes during heat stress indicates the importance of both genes in the response to high temperature in B. emersonii. (C) 2008 Elsevier B.V. All rights reserved.
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The opportunistic pathogen Pseudomonas aeruginosa PA14 possesses four fimbrial cup clusters, which may confer the ability to adapt to different environments. cupD lies in the pathogenicity island PAPI-1 next to genes coding for a putative phosphorelay system composed of the hybrid histidine kinase RcsC and the response regulator RcsB. The main focus of this work was the regulation of cupD at the mRNA level. It was found that the HN-S-like protein MvaT does not exert a strong influence on cupD transcript levels, as it does for cupA. cupD transcription is higher in cultures grown at 28 degrees C, which agrees with a cupD mutant presenting attenuated virulence only in a plant model, but not in a mouse model of infection. Whereas an rcsC in-frame deletion mutant presented higher levels of cupD mRNA, rcsB deletion had the opposite effect. Accordingly, overexpression of RcsB increased the levels of cupD transcription, and promoted biofilm formation and the appearance of fimbriae. A single transcription start site was determined for cupD and transcription from this site was induced by RcsB. A motif similar to the enterobacterial RcsB/RcsA-binding site was detected adjacent to the -35 region, suggesting that this could be the RcsB-binding site. Comparison of P. aeruginosa and Escherichia coli Rcs may provide insights into how similar systems can be used by different bacteria to control gene expression and to adapt to various environmental conditions.
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We have evaluated RECK (reversion-inducing-cysteine-rich protein with Kazal motifs), MMP-2 (matrix metalloproteinase-2), MMP-3, and MMP-9 involvement during palate development in mice by using various techniques. Immunohistochemical features revealed the distribution of RECK, MMP-2, and MMP-3 in the mesenchymal tissue and in the midline epithelial seam at embryonic day 13 (E13), MMPs-2, -3, and -9 being particularly expressed at E14 and E14.5. In contrast, RECK was weakly immunostained at these times. Involvement of MMPs was validated by measuring not only their protein expression, but also their activity (zymograms). In situ hybridization signal (ISH) for RECK transcript was distributed in mesenchymal and epithelial regions within palatal shelves at all periods evaluated. Importantly, the results from ISH analysis were in accord with those obtained by real-time polymerase chain reaction. The expression of RECK was found to be temporally regulated, which suggested possible roles in palatal ontogeny. Taken together, our results clearly show that remodeling of the extracellular matrix is finely modulated during secondary palate development and occurs in a sequential manner.
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The main objective of this thesis work is to develop communication link between Runrev Revolution (IDE) and JADE (Multi-Agent System) through Socket programming using TCP/IP layer. These two independent platforms are connected using socket programming technique. Socket programming is considered to be newly emerging technology among these two platforms, the work done in this thesis work is considered to be a prototype.A Graphical simulation model is developed by salixphere (Company in Hedemora) to simulate logistic problems using Runrev Revolution (IDE). The simulation software/program is called “BIOSIM”. The logistic problems are complex, and conventional optimization techniques are unlikely very successful. “BIOSIM” can demonstrate the graphical representation of logistic problems depending upon the problem domains. As this simulation model is developed in revolution programming language (Transcript) which is dynamically typed and English-like language, it is quite slow compared to other high level programming languages. The object of this thesis work is to add intelligent behaviour in graphical objects and develop communication link between Runrev revolution (IDE) and JADE (Multi-Agent System) using TCP/IP layers.The test shows the intelligent behaviour in the graphical objects and successful communication between Runrev Revolution (IDE) and JADE (Multi-Agent System).
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The ability to appropriately interact with the environment is crucial to an organism’s survival. The establishment of functional sensory systems, such as the bristles and eyes in Drosophila, is a critical event during the development of the organism. The transcription factor D Pax2 is involved in the differentiation of the shaft and glial cells in the developing bristle (Kavaler et al., Dev, 126:2261-2272, 1999) and of the cone and primary pigment cells in the developing eye (Fu and Noll, Genes Dev, 11:389-405, 1997). How D-Pax2 contributes to distinct differentiative pathways in different cell types is not known. Recent work by Anna Czechowski and Katherine Harmon (personal communication) identified a mutation in the D-Pax2 gene that introduced a stop codon at the end of exon 9, effectively truncating the protein. This mutation affects bristle, but not eye, development. We thus suspected regions after exon 9 are required for D-Pax2 function only in the bristles and may also be associated with alternative splicing of the D Pax2 transcript. We plan to assess the role of the carboxy terminal region of the protein by establishing transgenic lines bearing rescue constructs of D-Pax2 with either the complete coding sequence or with deletions of specific exons. To date, we have generated the first rescue construct bearing the complete coding region of the gene driven by a 3 KB upstream regulatory region of D-Pax2 and are currently generating transgenic fly lines with this construct.
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The xeroderma pigmentosum complementation group B (XPB) protein is involved in both DNA repair and transcription in human cells. It is a component of the transcription factor IIH (TFIIH) and is responsible for DNA helicase activity during nucleotide (nt) excision repair (NER). Its high evolutionary conservation has allowed identification of homologous proteins in different organisms, including plants. In contrast to other organisms, Arabidopsis thaliana harbors a duplication of the XPB orthologue (AtXPB1 and AtXPB2), and the proteins encoded by the duplicated genes are very similar (95% amino acid identity). Complementation assays in yeast rad25 mutant strains suggest the involvement of AtXPB2 in DNA repair, as already shown for AtXPB1, indicating that these proteins may be functionally redundant in the removal of DNA lesions in A. thaliana. Although both genes are expressed in a constitutive manner during the plant life cycle, Northern blot analyses suggest that light modulates the expression level of both XPB copies, and transcript levels increase during early stages of development. Considering the high similarity between AtXPB1 and AtXPB2 and that both of predicted proteins may act in DNA repair, it is possible that this duplication may confer more flexibility and resistance to DNA damaging agents in thale cress. (C) 2004 Elsevier B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Stress response is a universal mechanism developed by all organisms to deal with adverse changes in the environment, which lead to the synthesis of heat shock proteins (Hsps). In this study, the effect of moderate (41degreesC) and severe (44degreesC) heat stress on Hsp70 transcript expression pattern was investigated during chicken embryogenesis. Acute exposure to severe heat stress for one hour resulted in a fifteen-fold increase in Hsp70 mRNA levels. The return of stressed embryos to normal incubation temperature resulted in Hsp70 mRNA levels five-fold higher than control after three hours and normal levels after six hours. Moderate heat stress did not induce enhancements on Hsp70 mRNA levels. The spatial expression of Hsp70 transcripts was detected in embryos under normal incubation conditions. Whole-mount in situ hybridization analysis showed that Hsp70 transcripts were constitutively present in somite and in distinct encephalic domains (predominantly in prosencephalon and mesencephalon areas) of the chicken embryo. These results showed that Hsp70 induction is dependent on incubation temperature conditions, suggesting that early chicken embryos may induce a quick emergence response to cope with severe heat stress by increasing Hsp70 mRNA levels.
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The expression of the MyoD, myogenin, myostatin and Hsp70 genes was estimated in chicken embryos submitted to mild cold (36 +/- 0.5degreesC) or heat (44 +/- 0.5degreesC) for 1 h. 2. Marked decreases in MyoD, myogenin and myostatin transcript levels were observed in embryos exposed to high temperature, contrasting to the higher expression of the Hsp70 mRNA detected in heat-stressed embryos. 3. The exposure of chicken embryos to low temperature significantly affected only the abundance of myogenin mRNA. 4. These findings suggest that myogenic proliferation and differentiation events are compromised by variations in environmental temperature during avian embryogenesis. (C) 2003 Elsevier B.V. Ltd. All rights reserved.
Resumo:
This study aimed to understand the typical ideal of the nursing technician about the systematization of nursing care in the light of the theoretical framework of Alfred Schutz. It is a comprehensive phenomenological research, using the theoretical framework of Alfred Schutz. For the unveiling of the phenomenon (the typical ideal of the nursing technician about the systematization of nursing care), the search process was configured from the proposed guiding principles for a research methodology based on the work itself of Schutz held by Zeferino (2010) in his PhD. For data collection, we used the focus group technique, counting on the collaboration of thirteen practical nurses working in a university hospital in Rio Grande do Norte, who responded positively to the inclusion criteria: working in the study hospital, performing care direct to patients. Forty-four subjects showed interest in participating, being held a draw for selection of the research sample, consisting of 14 professionals, one of whom did not attend the gathering of data collection. The focus group, entitled "What I think about the systematization of nursing care", took place on February 15th, 2013, totaling 101 minutes. It was performed according to the Experiential Education Humanescent using building posters as projective technique, from the key question: "What is the systematization of nursing care for you?". In order to understand some of the biographical situation of the participants, a questionnaire was administered to study participants. From the agreement of the subjects, the focus group was recorded and photographed with the cooperation of one reporter and two other employees. We used Microsoft Word 2010 to perform the transcript of the meeting and Microsoft Excel 2010 for synthesizing the results via a spreadsheet. The study followed the ethical and legal principles that govern scientific research on humans, recommended in Resolution nº 196/96, it was approved by Opinion Embodied Ethics Committee in Research of UFRN (Federal University of Rio Grande do Norte), nº 98 424, of August 31th, 2012, CAAE No. 05906912.0.0000.5537. The analysis of the nursing staff speeches, along with the contemplation of their posters and their written descriptions, allowed from the guiding principles of Zeferino (2010), in light of the reference of Alfred Schutz, unveiling the typical ideal of nursing technicians about the systematization of nursing care, passing four themes: typing of the concept of systematization of nursing care; benefits, which resulted in the reasons to believe in the positivity of this working tool; experienced problems, revealing the world of everyday life of nursing professionals, and possibilities for improvement. It was concluded that the nursing technicians are unaware of the systematization of nursing care. However, they typify a very positive perception about the same, especially with regard to improvements that may foster care
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A collection of 237,954 sugarcane ESTs was examined in search of signal transduction genes. Over 3,500 components involved in several aspects of signal transduction, transcription, development, cell cycle, stress responses and pathogen interaction were compiled into the Sugarcane Signal Transduction (SUCAST) Catalogue. Sequence comparisons and protein domain analysis revealed 477 receptors, 510 protein kinases, 107 protein phosphatases, 75 small GTPases, 17 G-proteins, 114 calcium and inositol metabolism proteins, and over 600 transcription factors. The elements were distributed into 29 main categories subdivided into 409 sub-categories. Genes with no matches in the public databases and of unknown function were also catalogued. A cDNA microarray was constructed to profile individual variation of plants cultivated in the field and transcript abundance in six plant organs (flowers, roots, leaves, lateral buds, and 1(st) and 4(th) internodes). From 1280 distinct elements analyzed, 217 (17%) presented differential expression in two biological samples of at least one of the tissues tested. A total of 153 genes (12%) presented highly similar expression levels in all tissues. A virtual profile matrix was constructed and the expression profiles were validated by real-time PCR. The expression data presented can aid in assigning function for the sugarcane genes and be useful for promoter characterization of this and other economically important grasses.
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The electronic mail service is one of the most Internet services that grow in the corporate environment. This evolution is bringing several problems for the organizations, especially to information that circulates inside of the corporate net. The lack of correct orientation to the people, about the usage and the security importance of these resources, is leaving breaches and causing misusage and overuse of service, for example. In recent literature, it starts to coming out several ideas, which has helped to rganizations how to plain and how to implement the information security system to the electronic mail in computer environment. However, these ideas are still not placed in practice in many companies, public or private. This dissertation tries to demonstrate the results of a research that has like goal, identify the importance that user training has over the information security policy, through a case study inside of private superior education institute in this state. Besides, this work had by basic orientation the ISO/IEC 17799, which talk about People Security. This study was developed over a proposed model to this research, which looked for offer conditions to guide the institution studied, how to plan better a information security policy to the electronic mail. Also, this research has an exploratory and descreptive nature and your type, qualitative. Firstly, it was applied na questionary to the information technology manager, as better way to get some general data and to deepen the contact which still then, it was being kept through e-mail. Thereupon this first contact, eleven interviews were done with the same manager, beside one interview with twenty-four users, among employees e students. After that to collect and transcript the interviews, were review with the manager all informations given, to correct any mistakes and to update that informations, to then, start the data analyze. The research suggests that the institution has a pro attitude about the information security policy and the electronic mail usage. However, it was clear that answers have their perception about information security under a very inexperient way, derived of a planning lack in relation to training program capable to solve the problem
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Research about teacher education, carried out in the area of Applied Linguistics (AL), reveals the importance of reflective practices in the professional development of teachers. With the aim of contributing to this area, we present this case study conducted at a technical school in Natal, RN. The corpus of the study is formed mainly from the teacher‟s discourse, generated during a stimulated recall session and the instruments used to collect the data: an initial questionnaire, a video recording of a class and the text transcript of the stimulated recall session. The central objective is to understand the way in which the reflection-on-action (SCHÖN, 1983, 1987) can contribute to raise the awareness of an English as a Foreign Language teacher (EFL) about her actions in the classroom. With this proposal, we begin our discussion presenting the origins, the presuppositions and characteristics of the concept of reflection according to Schön (1983, 1987), and supported by other authors (PERRENOUD, 2002; GÓMEZ, 1995; IMBERNÓN, 2009, among others); of critical reflection (LISTON e ZEICHNER, 1993; PIMENTA, 2002; DUTRA e MELLO, 2004, among others); and of the process of critical reflection (SMYTH, 1992). To evidence the reflections that emerge in the teacher‟s discourse, we found support in the theories and methods of Systemic Functional Grammar (SFG), which was initially proposed by Halliday (1985, 1994), Halliday and Hasan (1989), Halliday and Matthiessen (2004) and followers, such as, Eggins (1994), Thompson (1996), among others. We focus mainly on the subsystem of Attitude, an integral component of the system of discourse resources, Appraisal, presented by Martin (2000), Martin and Rose (2003, 2007), Martin and White (2005). The results reveal that the actions of the teacher in the classroom reflect not only her professional experiences, but also her values and concepts about teaching/learning languages. The results also show the teacher‟s awareness of the need for changes in her practices. Faced with these findings, we believe that this study reveals important concepts that can direct teacher educators to rethink new ways of approaching teacher training courses. In addition, it also reveals the importance of discourse analysis based on a systemic functional approach.
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The human ZC3H14 gene encodes an evolutionarily conserved Cys(3)His zinc finger protein that binds specifically to polyadenosine RNA and is thus postulated to modulate post-transcriptional gene expression. Expressed sequence tag (EST) data predicts multiple splice variants of both human and mouse ZC3H14. Analysis of ZC3H14 expression in both human cell lines and mouse tissues confirms the presence of multiple alternatively spliced transcripts. Although all of these transcripts encode protein isoforms that contain the conserved C-terminal zinc finger domain, suggesting that they could all bind to polyadenosine RNA, they differ in other functionally important domains. Most of the alternative transcripts encode closely related proteins (termed isoforms 1, 2. 3, and 3short) that differ primarily in the inclusion of three small exons, 9, 10, and 11, resulting in predicted protein isoforms ranging from 82 to 64 kDa. Each of these closely related isoforms contains predicted classical nuclear localization signals (cNLS) within exons 7 and 11. Consistent with the presence of these putative nuclear targeting signals, these ZC3H14 isoforms are all localized to the nucleus. In contrast, an additional transcript encodes a smaller protein (34 kDa) with an alternative first exon (isoform, 4). Consistent with the absence of the predicted cNLS motifs located in exons 7 and 11, ZC3H14 isoform 4 is localized to the cytoplasm. Both EST data and experimental data suggest that this variant is enriched in testes and brain. Using an antibody that detects endogenous ZC3H14 isoforms 1-3 reveals localization of these isoforms to nuclear speckles. These speckles co-localize with the splicing factor, SC35, suggesting a role for nuclear ZC3H14 in mRNA processing. Taken together, these results demonstrate that multiple transcripts encoding several ZC3H14 isoforms exist in vivo. Both nuclear and cytoplasmic ZC3H14 isoforms could have distinct effects on gene expression mediated by the common Cys(3)His zinc finger polyadenosine RNA binding domain. (C) 2009 Elsevier B.V. All rights reserved.