977 resultados para Polimorfismo (Genética)


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The present study aimed to develop microsatellite markers (SSR) for Copernicia prunifera; and characterize the demographic pattern and the spatial genetic structure (SGS) in different development stages of C. prunifera in a natural population of Rio Grande do Norte (RN) by using ISSR molecular markers. 17 SSR primers pairs were developed, which were tested by using DNA from samples of different populations. The demographic and genetic spatial structure was assessed in a plot with an area of 0.55 ha, where all individuals were georeferenced. The molecular analyses with the use of microsatellite markers pointed out that all built primers pairs, when submitted to PCR, had amplification. They showed sizes of base pairs ranging between 113 and 250 bp. The demographic analyses showed a clustered standard of spatial distribution in the first distance classes, random between 40 and 50 m and segregated in higher distances. Eight ISSR primers were used, thereby producing a total of 102 loci, with 100 of them being polymorphic. Among the three stages, the young showed the highest Nei’s genetic diversity index (He = 0.37); whilst the lowest index was found in the reproductive adults (He = 0.34). The AMOVA results showed a greater genetic differentiation within the development stages (98.61%) in comparison to the interval among the stages (1.39%). The total population (n = 161) showed a positive and significant relationship of kinship in the first distance class (12.3 m). The young showed a significant kinship up to 10.5 m and negative in the fifth distance class (37.6 m). The non-reproductive adults had a positive relationship of kinship in the first distance class (11.0 m) and random distribution of genotypes in the remaining classes. The reproductive adults showed genotypes spatially distributed in a random way. The values for the genetic bottleneck tests proved that the number of loci with excess observed heterozygosity was greater than expected. The SGS results reflect the restricted dispersion of the species, and the bottleneck tests reflect the reduction genotypes provoked by the anthropization of natural environments of C. prunifera.

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Cryptography is the main form to obtain security in any network. Even in networks with great energy consumption restrictions, processing and memory limitations, as the Wireless Sensors Networks (WSN), this is no different. Aiming to improve the cryptography performance, security and the lifetime of these networks, we propose a new cryptographic algorithm developed through the Genetic Programming (GP) techniques. For the development of the cryptographic algorithm’s fitness criteria, established by the genetic GP, nine new cryptographic algorithms were tested: AES, Blowfish, DES, RC6, Skipjack, Twofish, T-DES, XTEA and XXTEA. Starting from these tests, fitness functions was build taking into account the execution time, occupied memory space, maximum deviation, irregular deviation and correlation coefficient. After obtaining the genetic GP, the CRYSEED and CRYSEED2 was created, algorithms for the 8-bits devices, optimized for WSNs, i.e., with low complexity, few memory consumption and good security for sensing and instrumentation applications.

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Cryptography is the main form to obtain security in any network. Even in networks with great energy consumption restrictions, processing and memory limitations, as the Wireless Sensors Networks (WSN), this is no different. Aiming to improve the cryptography performance, security and the lifetime of these networks, we propose a new cryptographic algorithm developed through the Genetic Programming (GP) techniques. For the development of the cryptographic algorithm’s fitness criteria, established by the genetic GP, nine new cryptographic algorithms were tested: AES, Blowfish, DES, RC6, Skipjack, Twofish, T-DES, XTEA and XXTEA. Starting from these tests, fitness functions was build taking into account the execution time, occupied memory space, maximum deviation, irregular deviation and correlation coefficient. After obtaining the genetic GP, the CRYSEED and CRYSEED2 was created, algorithms for the 8-bits devices, optimized for WSNs, i.e., with low complexity, few memory consumption and good security for sensing and instrumentation applications.

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Leishmania infantum is the main etiologic agent of visceral leishmaniasis in the New World. The pattern of distribution of leishmaniasis has changed substantially and has presented an emerging profile within the periphery of the Large Urban Centers. Leishmania infection can compromise skin, mucosa and viscera. Only 10% of the individuals infected develop the disease and 90% of human infection is asymptomatic. The main factors involved in the development of the disease are the host immune response, the vector’s species and the parasite’s genetic content. The sequencing of Leishmania isolated seeks to increase the understanding of the symptoms of individuals. The aim of this study was to evaluate the genetic diversity of circulating Leishmania strains among humans, and symptomatic and asymptomatic, and dogs from endemic areas of Rio Grande do Norte State and analyze sandflies from endemic areas for cutaneous and visceral disease. The genetic variability was evaluated by the use of markers hsp70 , ITS1 and a whole genome sequencing was also carried out. The amplified hsp70 and ITS1 of samples were analyzed and assembled using a Phred / Phrap package. The dendograms were constructed using the same methodology, but adding 500 bootstraps, followed by inferences on the relationships between Leishmania variants. The sequences of the 20 Brazilian isolates were mapped to the reference genome L. infantum JPCM5, using the Bowtie2 program and the identification of 36 contigs. The information of the valid SNPs were used in the PCA. SNPs were visualized by Geneious 7.1 and IGV. The genome annotations were transferred to their respective chromosomes and displayed on Geneious. The matching sequences of all chromosomes were aligned using Mauve. The phylogenetic trees were calculated according to maximum likelihood and JTT models. Sandflies were analyzed by PCR for the identification of Leishmania infection, a blood meal source and GAPDH sand fly. As a result, hsp70 and ITS1 were not capable of identifying genetic variability among human isolates from symptomatic and asymptomatic, and dogs. The complete sequencing of the 20 Brazilian isolates revealed a strong similarity between the circulating Leishmania strains in Rio Grande do Norte. The isolates collected in the city of Natal from humans and canines remained grouped in all analyzes, suggesting that there is genotypic and geographic proximity among the isolates. The isolated samples in the 1990s had a higher genotypic diversity when compared to freshly isolated samples. All isolates presented 36 chromosomes with variable ploidy among them, no correlation was found between the number of amastina genes copies, gp63, A2 and SSG with such clinic forms. In general, we did not find correlation between symptomatic and asymptomatic clinical forms and the gene content of the Brazilian isolates of Leishmania. 34,28% of the sandflies collected in the upper west region were L. longipalpis and the main sources of blood meal were humans, dogs and chickens.

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Leishmania infantum is the main etiologic agent of visceral leishmaniasis in the New World. The pattern of distribution of leishmaniasis has changed substantially and has presented an emerging profile within the periphery of the Large Urban Centers. Leishmania infection can compromise skin, mucosa and viscera. Only 10% of the individuals infected develop the disease and 90% of human infection is asymptomatic. The main factors involved in the development of the disease are the host immune response, the vector’s species and the parasite’s genetic content. The sequencing of Leishmania isolated seeks to increase the understanding of the symptoms of individuals. The aim of this study was to evaluate the genetic diversity of circulating Leishmania strains among humans, and symptomatic and asymptomatic, and dogs from endemic areas of Rio Grande do Norte State and analyze sandflies from endemic areas for cutaneous and visceral disease. The genetic variability was evaluated by the use of markers hsp70 , ITS1 and a whole genome sequencing was also carried out. The amplified hsp70 and ITS1 of samples were analyzed and assembled using a Phred / Phrap package. The dendograms were constructed using the same methodology, but adding 500 bootstraps, followed by inferences on the relationships between Leishmania variants. The sequences of the 20 Brazilian isolates were mapped to the reference genome L. infantum JPCM5, using the Bowtie2 program and the identification of 36 contigs. The information of the valid SNPs were used in the PCA. SNPs were visualized by Geneious 7.1 and IGV. The genome annotations were transferred to their respective chromosomes and displayed on Geneious. The matching sequences of all chromosomes were aligned using Mauve. The phylogenetic trees were calculated according to maximum likelihood and JTT models. Sandflies were analyzed by PCR for the identification of Leishmania infection, a blood meal source and GAPDH sand fly. As a result, hsp70 and ITS1 were not capable of identifying genetic variability among human isolates from symptomatic and asymptomatic, and dogs. The complete sequencing of the 20 Brazilian isolates revealed a strong similarity between the circulating Leishmania strains in Rio Grande do Norte. The isolates collected in the city of Natal from humans and canines remained grouped in all analyzes, suggesting that there is genotypic and geographic proximity among the isolates. The isolated samples in the 1990s had a higher genotypic diversity when compared to freshly isolated samples. All isolates presented 36 chromosomes with variable ploidy among them, no correlation was found between the number of amastina genes copies, gp63, A2 and SSG with such clinic forms. In general, we did not find correlation between symptomatic and asymptomatic clinical forms and the gene content of the Brazilian isolates of Leishmania. 34,28% of the sandflies collected in the upper west region were L. longipalpis and the main sources of blood meal were humans, dogs and chickens.

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Lo studio del polimorfismo gioca un ruolo fondamentale in diversi ambiti di ricerca, con applicazioni importanti nel campo dei semi conduttori organici e dei farmaci, dovuto al fatto che i diversi polimorfi di una sostanza presentano proprietà chimico-fisiche distinte. Questo lavoro di tesi si è focalizzato sullo studio del polimorfismo del paracetamolo, principio attivo (API) di diversi farmaci molto utilizzati, attraverso l’utilizzo della microscopia Raman. La microscopia Raman è una tecnica efficace per l’indagine del polimorfismo di materiali organici ed inorganici, in quanto permette di monitorare la presenza di diverse fasi solide e le loro trasformazioni su scala micrometrica. Le differenze di struttura cristallina che caratterizzano i polimorfi vengono analizzate attraverso gli spettri Raman nella regione dei modi reticolari (10-150 cm^{-1}), le cui frequenze sondano le interazioni inter-molecolari, molto sensibili anche a lievi differenze di impaccamento molecolare. Con questa tecnica abbiamo caratterizzato le forme I, II, III (quella elusiva) e diverse miscele di fase di paracetamolo su campioni ottenuti con numerose tecniche di crescita dei cristalli. Per questa tesi è stato svolto anche uno studio computazionale, attraverso metodi Density Functional Theory (DFT) per la molecola isolata e metodi di minimizzazione dell’energia e di dinamica reticolare per i sistemi cristallini. Abbiamo inoltre verificato se il modello di potenziale di letteratura scelto (Dreiding [Mayo1990]) fosse adatto per descrivere la molecola di paracetamolo, le strutture dei suoi polimorfi e i relativi spettri vibrazionali.

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Salmonella Enteritidis, S. Typhimurium and S. Infantis are often associated with cases of human infections worldwide and is transmitted through consumption of contaminated food, particularly those of animal origin, especially chicken meat. This thesis was fractionated into three chapters, the first one relating to general considerations about the topics discussed in the following chapters. The second chapter aimed to evaluate virulence characteristics, antimicrobial resistance and the genetic similarity of 51 strains of S. Infantis isolated in samples of poultry origin from an industry located in the state of São Paulo, Brazil, during the 2009 to 2010 period. The third chapter aimed to analyze 111 strains of S. Enteritidis, 45 of Salmonella Typhimurium and 31 of Salmonella Typhimurium monophasic variant I 4, [5], 12:i:- isolated from chicken carcasses in different brazilian slaughterhouses from 2009 to 2011, and to estimate the risk to human health, based on the presence of virulence genes and antimicrobial resistance, correlating to the pathogenicity profiles (antimicrobial resistance and presence of virulence and resistance genes) with the genetic profile (ribogroup) of the isolates. To evaluate the antimicrobial susceptibility was performed the disk diffusion test for all serotypes of Salmonella, and exclusively to S. Enteritidis and S. Typhimurium, was also verified the minimum inhibitory concentration for ciprofloxacin and ceftazidime antibiotics. The presence of virulence genes invA (invasion), lpfA (fimbriae-adhesion), agfA (fimbriae-biofilm) and sefA (fimbriae-adhesion) were evaluated by PCR. The strains that showed resistance to antibiotics of β-lactams class were evaluated for the presence of resistance genes blaTEM, blaSHV, blaCTX-M and blaAmpC. For resistant strains to quinolones and fluoroquinolones antibiotics classes were searched the qnrA and qnrS genes. The phylogenetic relationship among the isolates was determined by RAPD method for S. Infantis strains, and by ribotyping technique to S. Enteritidis and S. Typhimurium.

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El presente trabajo tiene su origen en la necesidad de herramientas de apoyo al aprendizaje para los alumnos en las clases de Genética de la Facultad de Biología de la Universidad Complutense de Madrid. En esta asignatura, el equipo docente ha desarrollado aplicaciones para dispositivos móviles destinadas a los alumnos. Las aplicaciones les permiten trabajar con materiales relacionados con aspectos clave de la asignatura. Estas aplicaciones contienen apartados de teoría y ejercicios. Los ejercicios cuentan con asistentes automatizados que guían al alumno para su realización y autocorrección. En su forma actual, las aplicaciones presentan limitaciones tanto desde el punto de vista de su diseño como de la funcionalidad que ofrecen. El actual diseño no aplica las técnicas comunes de Ingeniería del Software respecto a aplicaciones cliente-servidor. Ello las hace difíciles de mantener cuando se plantea abordar nuevas funcionalidades y plataformas, o facilitar la creación de nuevos materiales de la asignatura. Ello ha limitado su expansión para incorporar nuevos tipos de materiales (en particular diferentes tipos de ejercicios), integrarlas con otras herramientas (por ejemplo, el Campus Virtual de la universidad) o permitir un apoyo efectivo a la comunidad de aprendizaje formada por alumnos y docentes (por ejemplo, para que los docentes supervisen la evolución de los alumnos y estos puedan obtener información adicional de los profesores). Para abordar esta situación se propone una aplicación móvil que engobe a todas las aplicaciones anteriores que se habían creado para las clases de Genética. Se utilizará un modelo cliente-servidor para mejorar sus capacidades funcionales, de modo que cumpla con los requisitos establecidos. Entre estos se incluye un control de los usuarios que utilizan la aplicación, y que se optimice la memoria local utilizada por la aplicación, permitiendo así el uso de imágenes más pesadas. Además, este modelo facilitará las tareas de mantenimiento de la aplicación, por ejemplo incluir nuevo material. Por otro lado, también se propone rediseñar la interfaz de la aplicación, de modo que sea más accesible desde el punto de vista de la usabilidad.

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Programa de doctorado: Salud pública: Epidemiología, nutrición y planificación

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Programa de doctorado: Actividad Física, Salud y Rendimiento Deportivo

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Programa de doctorado: Oceanografía, Bienio 2007/09. La fecha de publicación es la fecha de lectura

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Introdução: A parentalidade é um papel muito valorizado socialmente. No entanto, para casais com infertilidade o desempenho deste papel pode implicar tratamentos de fertilidade, alguns deles com recurso a gâmetas de dador. Para os casais que recorrem a gâmetas de dador, surge uma outra preocupação: contar à criança a origem da sua conceção ou manter segredo. Ainda que as motivações que influenciam este processo de decisão tenham sido alvo de estudo, em Portugal a investigação relativa a este tema é escassa. Objetivos: A presente investigação pretendeu desenvolver e estudar a validade facial do Questionário de Motivações para Revelar/Não Revelar a Parentalidade não Genética por Doação de Gâmetas (QMRDG), o qual se destina a avaliar as principais motivações que influenciam o processo de tomada de decisão dos pais que recorrem a gâmetas de dador relativamente a contar ou não contar ao/à seu/sua filho/a a origem da sua conceção. Pretendeu-se ainda explorar a relação entre os sintomas emocionais negativos e o sentido de competência parental nos diferentes grupos em estudo (pais que já contaram à criança, pais que decidiram não contar e pais que ainda não contaram). Metodologia: Estudo exploratório conduzido numa amostra de 21 participantes que recorrem a tratamento de fertilidade com recurso a gâmetas de dador, tendo tido filhos resultantes desse mesmo tratamento, com idades compreendidas entre os 30 e 49 anos. Os participantes preencheram um conjunto de questionários numa plataforma online, tendo o estudo sido divulgado pela Associação Portuguesa de Fertilidade. Resultados: Os dados obtidos indicam que a maioria dos pais ainda não contou ao/à seu/sua filho/a sua origem genética devido ao facto de a criança ser ainda muito pequena, encontrando-se estes com intenção de revelar à criança. Dos pais que já contaram, as motivações que mais influenciaram a decisão basearam-se na falta de motivos para omitir, na importância dada à honestidade, no direito do conhecimento das origens genéticas e na transparência no seio familiar. Face às motivações para não contar, das que mais influenciaram os pais salienta-se a pouca importância dada à genética. O QMRDG revelou possuir validade facial não tendo sido reportada a existência de itens ambíguos ou de difícil compreensão. Discussão: A tendência dos pais no presente estudo foi de contar ao/à seu/sua filho/a a origem da sua conceção, sendo também esta a tendência reportada em estudos mais recentes. Verificou-se a existência de algumas limitações no estudo, nomeadamente o tamanho da amostra. No entanto, o QMRDG mostrou possuir validade facial, podendo constituir-se como um instrumento útil na prática clínica e na investigação com pessoas que estejam a realizar tratamento de fertilidade com recurso a gâmetas de dador. / Introduction: Parenting is a highly valued social role. However, for couples dealing with infertility this role can involve fertility treatments, and for some of them donorassisted reproduction. For couples who use third party reproduction, another concern can emerge: tell the child about the donor conception, or preserve secrecy. Although arguments for decision making have been studied, in Portugal research on this topic is scanty. Objectives: The current study sought out to develop and study the facial validity of Motivations for Disclosing/Not Disclosing Non-genetic Parenthood through Gamete Donation (QMRDG), which is designed to assess motivations that influence the decision-making process of parents who use gamete donation regarding tell or not to tell to his/her son/daughter his/her conception. The existence of differences concerning emotional negative symptoms and parenting sense of competence in three groups (parents that already disclosed, parents that decided not to disclose and parents that did not decide what to do) was also explored. Methods: This exploratory study was conducted in sample of 21 participants who undergone third-party reproduction treatment and became parents. Participants´ age ranged from 30 to 49 years. Participants completed a set of questionnaires through an online platform. The study was advertised by Associação Portuguesa de Fertilidade. Results: Data showed that most parents did not disclose to their child their donor conception due to the fact that the child is still very young, but their intention seems to be to disclose in the future. For parents who have disclosed, core motivations for that decision are based on the lack of reasons for omitting, on the importance of honesty, on the right to know genetic origins and on transparency in the family. Concerning motivations for not disclosing the little importance given to genetics emerges as one of the most important ones. QMRDG revealed good facial validity. The existence of ambiguous or difficult to understand items has not been reported. Discussion: In our study parent’s tendency was to disclose to his/her son/daughter his/her donor conception and this is also the trend reported in recent studies. There are some methodological limitations that should be considered mainly due to the sample size. However, the QMRDG proved to be an instrument showing facial validity, and it can be a useful tool in clinical practice and research with people who are pursuing fertility treatment with gamete donation.

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BACKGROUND: Asthma and rhinitis have a complex etiology, depending on multiple genetic and environmental risk factors. An increasing number of susceptibility genes are currently being identified, but the majority of reported associations have not been consistently replicated across populations of different genetic backgrounds. PURPOSE: To evaluate whether polymorphisms of IL4R (rs1805015), IL13 (rs20541), IL17A (rs2275913) and GSTP1 (rs1695) genes are associated with rhinitis and/or asthma in adults of Portuguese ancestry. METHODS: 192 unrelated healthy individuals and 232 patients, 83 with rhinitis and 149 with asthma, were studied. All polymorphisms were detected by real time polymerase chain reaction (PCR) using TaqMan assays. RESULTS: Comparing to controls, significant association with asthma was observed for GSTP1 rs1695 AA genotype (odds ratio (OR) - 1.96; 95% CI - 1.18 to 3.25; p=0.010). The association sustains for allergic asthma (OR - 2.17; 95% CI - 1.23 to 3.80; p=0.007). IL13 rs20541 GG genotype was associated with less susceptibility to asthma (OR - 0.55, 95% CI - 0.33 to 0.94, p=0.028). Among patients, IL17A rs2275913 AA genotype was less associated with asthma than with rhinitis (OR - 0.20; 95% CI of 0.07 to 0.56; p=0.002). A similar association was found for IL13 rs20541 GG genotype (OR - 0.48; 95% CI of 0.25 to 0.93; p=0.031). There were no significant differences in the distribution of allelic and genotypic frequencies between patients and controls for the IL4R polymorphism' analyzed. CONCLUSION: These results support the existence of a significant association between GSTP1 rs1695 and IL13 rs20541 SNPs, with susceptibility to asthma, in the population studied. Different genotype profiles of IL17A and IL13 genes seem to influence the clinical pattern of disease expression mainly confined to the upper airways, as rhinitis, or including the lower airways, as asthma.

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Ranas clasificadas como ranas pipiens representan a un grupo de especies relacionadas. En este trabajo se compararon cuatro poblaciones de este grupo viviendo en Costa Rica en alturas y en medios ambientes diferentes en cuanto a morfología y compatibilidad reproductiva. No existe una diferencia significativa entre la forma del rostro en las poblaciones estudiadas, pero al tamaño promedio de ambos sexos disminuye a un “cline” (grado) con incremento de altura. Cruces artificiales indican una reducción significativa en la compatibilidad reproductiva entre la población más alta y las más bajas. Se propone que el cambio clinal en tamaño y la incompatibilidad reproductiva de la población alta representa una divergencia genética y posiblemente una especie nueva en proceso de formación. Se propone también que una “especiación” parecida pueda estar ocurriendo en otras montañas y volcanes de América Central en varios grupos de organismos.