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Iowa Code section 324A.4, subsection 2, states the Iowa Department of Transportation (DOT) “shall biennially prepare a report to be submitted to the general assembly and the governor prior to December 15 of even-numbered years. The report shall recommend methods to increase transportation coordination and improve the efficiency of federal, state, and local government programs used to finance public transit services and may address other topics as appropriate.” Iowa has long been a leader in transportation coordination, from designated public transit agencies covering all 99 counties with little duplication, to requiring any agency receiving public dollars for the provision of transportation to first coordinate with the local public transit agency before providing the transportation on their own, to the creation of the Iowa Transportation Coordination Council. Coordination allows Iowa to provide much needed transportation services to the citizens of Iowa with the most efficient use of public funds. Coordination has been an important topic in Iowa for many years, but during these times of economic constraint and restraint and Iowa’s changing demographics, coordination of transportation services becomes even more critical.

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La synthèse d’un ARNm eucaryotique dépend d’une suite d’étapes qui inclut notamment l’ajout d’une queue poly(A) à son extrémité 3’. Au noyau, la queue poly(A) des ARNms est liée par PABPN1 (poly(A)-binding protein nuclear 1). PABPN1 fut notamment caractérisée, d’après des études in vitro, pour stimuler la réaction de polyadénylation en plus de contrôler la taille ultime des queues poly(A). Cela dit, la ou les fonction(s) biologique(s) de PABPN1 est/sont cependant largement méconnue(s). Chez Schizosaccharomyces pombe (S. pombe), Pab2 est l’orthologue présumé de PABPN1. Or, mes travaux indiquent que Pab2 est fonctionnellement différente de PABPN1 à l’égard de son rôle sur le processus général de polyadénylation. Ainsi, in vivo, l’absence de Pab2 entraîne l’expression et l’accumulation d’un groupe limité d’ARNs hyperadénylés parmi lesquels se trouvent de nombreux petits ARNs nucléolaires non-codants (snoRNAs) lesquels constituent normalement un groupe abondant d’ARN poly(A)-. Mes résultats supportent ainsi un mécanisme par lequel des snoRNAs immatures poly(A)+, sont convertis en une forme mature poly(A)- par le biais de Pab2 et de l’activité 3’-->5’ exoribonucléase de l’exosome à ARN. Ces observations sont inusitées dans la mesure où elles associent une fonction pour une PABP dans la maturation d'ARNs non-codants, contrairement à la notion que les PABPs travaillent exclusivement au niveau des ARNms, en plus de procurer une nouvelle perspective face au mécanisme de recrutement de l'exosome à ARN à des substrats poly(A)+. La formation de l’extrémité 3’ d’un ARN est un processus étroitement lié à la terminaison de sa transcription. Pour les gènes codants, la terminaison transcriptionnelle est initiée par le clivage endonucléolytique du pré-ARNm. Ce clivage génère une extrémité d’ARN 5’ libre laquelle sera ciblée par une exoribonucléase 5'-->3’ afin de mener à bien l’éviction de l’ARNPII de la matrice d’ADN (terminaison transcriptionnelle de type torpedo). Au contraire, chez Saccharomyces cerevisiae (S. cerevisiae), la majorité des gènes non-codants, incluant les snoRNAs, dépendent plutôt du complexe NNS (Nrd1/Nab3/Sen1) pour la terminaison de leur transcription. Cela dit, il est incertain si le complexe NNS est conservé chez d’autres espèces. À cet égard, mes travaux indiquent que S. pombe est dépourvu d’un mécanisme de terminaison de la transcription de type NNS. Seb1, l’orthologue présumé de Nrd1 chez S. pombe, s’associe plutôt à la machinerie de clivage et de polyadénylation et influence la sélection de site de polyadénylation à l’échelle du génome. Mes résultats supportent ainsi l’utilisation de la machinerie de maturation 3’ des ARNms comme principal vecteur de terminaison transcriptionnelle chez S. pombe et identifient Seb1 comme un facteur clé de ce processus. L’évènement transcriptionnel étant hautement complexe, des erreurs peuvent arriver de manière stochastique menant à l’accumulation d’ARNs aberrants potentiellement néfastes pour la cellule. Or, mes travaux ont mis en lumière un mécanisme de surveillance co-transcriptionnel des ARNs impliquant l’exosome à ARN et lié à la terminaison de la transcription. Pour ce faire, l’exosome à ARN promeut la terminaison transcriptionnelle via la dégradation d’une extrémité 3’ libre d’ARN devenue émergente suite au recul de l’ARNPII le long de la matrice d’ADN (phénomène de backtracking). Mes résultats supportent ainsi une terminaison de la transcription de type torpedo inversé (3'-->5’) réévaluant par la même occasion le concept voulant que la terminaison de la transcription s’effectue uniquement selon une orientation 5’-->3’. Somme toute, mes travaux de doctorat auront permis d’identifier et de caractériser plus en détail les facteurs et mécanismes impliqués dans la maturation 3’ et la terminaison de la transcription des gènes codants et non-codants chez l’organisme modèle S. pombe.

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INTRODUCCIÓN. La distrofia muscular de Duchenne es una enfermedad neuromuscular con una herencia recesiva ligada al X que afecta a 1 de cada 3500 niños nacidos vivos. Se produce por mutaciones en el gen DMD que codifica para la distrofina. Se caracteriza por manifestaciones clínicas variables típicas de una distrofia muscular proximal progresiva. OBJETIVO. Realizar el primer registro en Colombia de los pacientes identificados con distrofinopatías, teniendo en cuenta características clínicas y paraclínicas, así como las mutaciones causales de esta patología. METODOLOGÍA Es un estudio descriptivo, transversal, de la revisión de historias clínicas de los pacientes con diagnóstico de DMD atendidos en la consulta de Genética de la Universidad del Rosario durante los años 2006 a 2015. RESULTADOS Se identificaron 99 pacientes, de los cuales 56 (56,56%) corresponden al fenotipo Duchenne y 12 (12,12%) al Becker. No fue posible clasificar a 31 pacientes (31,3%) por falta de datos clínicos. La edad de inicio de los síntomas fue en promedio de 4,41 años. Las mutaciones más frecuentes fueron las deleciones (69%), seguidas por las mutaciones puntuales(14%), las duplicaciones (11%) y por otras mutaciones (4%). CONCLUSIONES Este registro de distrofinopatías es el primero reportado en Colombia y el punto de partida para conocer la incidencia de la enfermedad, caracterización clínica y molecular de los pacientes, garantizando así el acceso oportuno a los nuevos tratamientos de medicina de precisión que permitan mejorar la calidad de vida de los pacientes y sus familias.

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Morocco was the last North African country in which a Pasteur institute was created, nearly two decades later than in Tunisia and Algeria. In fact, two institutes were opened, the first in Tangier in 1913 and the second in Casablanca in 1932. This duplication, far from being a measure of success, was the material expression of the troubles Pastorians had experienced in getting a solid foothold in the country since the late 19th century. These problems partly derived from the pre-existence of a modest Spanish-Moroccan bacteriological tradition, developed since the late 1880s within the framework of the Sanitary Council and Hygiene Commission of Tangier, and partly from the uncoordinated nature of the initiatives launched from Paris and Algiers. Although a Pasteur Institute was finally established, with Paul Remlinger as director, the failure of France to impose its colonial rule over the whole country, symbolized by the establishment of an international regime in Tangier, resulted in the creation of a second centre in Casablanca. While elucidating many hitherto unclear facts about the entangled origins of both institutes, the author points to the solidity of the previously independent Moroccan state as a major factor behind the troubled translation of Pastorianism to Morocco. Systematically dismissed or downplayed by colonial and postcolonial historiography, this solidity disrupted the French takeover of the country and therefore Pastorian expectations.

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The duckweed Lemna valdiviana is commonly founded colonizing small shallow waters (lakes on the lowland in south Brazil. This organism may have been affected by herbicide input into lakes from aerial application and/or drainage office paddy fields. Clomazone (2- (2-chlorophenyl) methyl-4.4-dimethyl-3-isoxazolidinone) is one of the herbicides more fiequentely used as post-emergence in rice paddies. For this work assays were carried as EC50(96h) semi-statics with aseptic culture. The sterile fronds were abtained from material harvest on the paddy fields, and the concentration of Clomazone ranged from 14.0 to 229.0 mg/l. two procedures were considered: diluted in water and sprayed applicated Clomazone. The observed phytotoxic effects were evaluated by growth rate (kt), duplication time (Td), frond yield, plant yield, mortality, chlorophyll a and b and protochlorophyll concentration. The EC50 values obtained to sprayed Clomazone (Kt=31.7; Td=31.9) were significantly small than to diluted Clomazone (Kt=46.4; td=47.3). These dadta suggest that aerial route is more hazardous than diluted procedure. Presence of chlorotic, necrotic, abnormal and died frond were common at the 114.0 and 229.0 mg/l treatment. Recuperation test corroborated the evidence that the sprayed procedure were more deleterious and L. valdiviana doesn't recovery his reproductive ability at the 114.0 and 229.0 mg/l treatment.

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MYCN amplification is a genetic hallmark of the childhood tumour neuroblastoma. MYCN-MAX dimers activate the expression of genes promoting cell proliferation. Moreover, MYCN seems to transcriptionally repress cell differentiation even in absence of MAX. We adopted the Drosophila eye as model to investigate the effect of high MYC to MAX expression ratio on cells. We found that dMyc overexpression in eye cell precursors inhibits cell differentiation and induces the ectopic expression of Antennapedia (the wing Hox gene). The further increase of MYC/MAX ratio results in an eye-to-wing homeotic transformation. Notably, dMyc overexpression phenotype is suppressed by low levels of transcriptional co-repressors and MYCN associates to the promoter of Deformed (the eye Hox gene) in proximity to repressive sites. Hence, we envisage that, in presence of high MYC/MAX ratio, the “free MYC” might inhibit Deformed expression, leading in turn to the ectopic expression of Antennapedia. This suggests that MYCN might reinforce its oncogenic role by affecting the physiological homeotic program. Furthermore, poor neuroblastoma outcome associates with a high level of the MRP1 protein, encoded by the ABCC1 gene and known to promote drug efflux in cancer cells. Intriguingly, this correlation persists regardless of chemotherapy and ABCC1 overexpression enhances neuroblastoma cell motility. We found that Drosophila dMRP contributes to the adhesion between the dorsal and ventral epithelia of the wing by inhibiting the function of integrin receptors, well known regulators of cell adhesion and migration. Besides, integrins play a crucial role during synaptogenesis and ABCC1 locus is included in a copy number variable region of the human genome (16p13.11) involved in neuropsychiatric diseases. Interestingly, we found that the altered dMRP/MRP1 level affects nervous system development in Drosophila embryos. These preliminary findings point out novel ABCC1 functions possibly defining ABCC1 contribution to neuroblastoma and to the pathogenicity of 16p13.11 deletion/duplication

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Down syndrome (DS) or trisomy 21 (T21) is the most common genetic cause of intellectual disability (ID). Subjects with DS are characterized by complex and variable clinical features including intellectual disability (ID) and craniofacial dysmorphisms. The aim of the thesis is to uncover genotype-phenotype relationships in DS possibly useful to devise therapies based on molecular and cellular mechanisms. In this work, we have investigated different aspects of DS: - we have collected clinical data of children with DS and we have evaluated the cognitive impairment through specific cognitive tests - we have analysed genomics of DS through the study of partial trisomy (PT21) cases. We have described new PT21 cases confirming the hypothesis of the highly restricted DS critical region (HR-DSCR) recently identified as the minimal region whose duplication is shared by all PT21 subjects diagnosed with DS, while it is absent in all PT21 non-DS subjects. Moreover, we have characterized new transcripts included in the HR-DSCR; - we have studied gene expression through RNAseq in blood cells of children with DS; -metabolic alterations in plasma of children with DS were identified through different methods: Nuclear Magnetic resonance, routine blood exams performed during the follow up of the subjects and enzyme-linked immunosorbent assay (ELISA); - to test possible correlations between specific Hsa21 regions and alterations in transcriptomics and metabolomics, we have used trisomic iPSCs and differentiated them into neuronal derivatives. Significant alterations in gene expression and metabolic profiles have been identified, as well as significant correlations with clinical and cognitive aspects. Specific genes and the HR-DSCR may play a role in these alterations: cell models need to be developed to investigate this role. Neural derivatives from trisomic iPSCs are a promising model to better understand genotype-phenotype correlations in DS.