962 resultados para Splicing Variant


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A general overview of the protein sequence set for the mouse transcriptome produced during the FANTOM2 sequencing project is presented here. We applied different algorithms to characterize protein sequences derived from a nonredundant representative protein set (RPS) and a variant protein set (VPS) of the mouse transcriptome. The functional characterization and assignment of Gene Ontology terms was done by analysis of the proteome using InterPro. The Superfamily database analyses gave a detailed structural classification according to SCOP and provide additional evidence for the functional characterization of the proteome data. The MDS database analysis revealed new domains which are not presented in existing protein domain databases. Thus the transcriptome gives us a unique source of data for the detection of new functional groups. The data obtained for the RPS and VPS sets facilitated the comparison of different patterns of protein expression. A comparison of other existing mouse and human protein sequence sets (e.g., the International Protein Index) demonstrates the common patterns in mammalian proteornes. The analysis of the membrane organization within the transcriptome of multiple eukaryotes provides valuable statistics about the distribution of secretory and transmembrane proteins

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Recent population studies have demonstrated an association with the red-hair and fair-skin phenotype with variant alleles of the melanocortin-1 receptor (MC1R) which result in amino acid substitutions within the coding region leading to an altered receptor activity. In particular, Arg151Cys, Arg160Trp and Asp294His were the most commonly associated variants seen in the south-east Queensland population with at least one of these alleles found in 93% of those with red hair. In order to study the individual effects of these variants on melanocyte biology and melanocytic pigmentation, we established a series of human melanocyte strains genotyped for the MC1R receptor which included wild-type consensus, variant heterozygotes, compound heterozygotes and homozygotes for Arg151Cys, Arg160Trp, Val60Leu and Val92Met alleles. These strains ranged from darkly pigmented to amelanotic, with all strains of consensus sequence having dark pigmentation. UV sensitivity was found not to be associated with either MC1R genotype or the level of pigmentation with a range of sensitivities seen across all genotypes. Ultrastructural analysis demonstrated that while consensus strains contained stage IV melanosomes in their terminal dendrites, Arg151Cys and Arg160Trp homozygote strains contained only stage II melanosomes. This was despite being able to show expression of tyrosinase and tyrosinase-related protein-1 markers, although at reduced levels and an ability to convert exogenous 3,4-dihydroxyphenyl-alanine (DOPA) to melanin in these strains.

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We have studied the expression of the green fluorescent protein (GFP) gene to gain more understanding of the effects of additional nucleotide triplets (codons) downstream from the initiation codon on the translation of the GFP mRNA in CHO and Cos1 cells. A leader sequence of six consecutive identical codons (GUG, CUC, AGU or UCA) was introduced into a humanized GFP (hm gfp) gene downstream from the AUG to produce four GFP gene variants. Northern blot and RT-PCR analysis indicated that mRNA transcription from the GFP gene was not significantly affected by any of the additional sequences. However, immunoblotting and FACS analysis revealed that AGU and UCA GFP variants produced GFP at a mean level per cell 3.5-fold higher than the other two GFP variants and the hm gfp gene. [35S]-Methionine labeling and immunoprecipitation demonstrate that GFP synthesis was very active in UCA variant transfected-cells, but not in GUG variant and hm gfp transfected-cells. Moreover, proteasome inhibitor MG-132 treatment indicated that the GFPs encoded by each of the GFP variants and the hm gfp were equally stable, and this together with the comparable mRNA levels observed for each construct suggested that the different steady-state GFP concentrations observed reflected different translation efficiencies of the various GFP genes. In addition, the CUC GFP variant, when transiently transfected into CHO or COS-1 cells, did not produce any GFP expressing cells (fully green cells), and the GUG variant produced GFP expressing cells less than 10%, while AGU and UCA GFP variants up to 30–35% in a time course study from 8 to 36 h posttransfection. Analysis of the potential secondary structure of the GFP variant mRNAs especially in the translation initiation region suggested that the secondary structure of the GFP mRNAs was unlikely to explain the different translation efficiencies of the GFP variants. The present findings indicate that a change of the initiation context of the GFP gene by addition of extra coding sequence can alter the translation efficiency of GFP mRNA, providing a means of more efficient expression of GFP in eukaryotic cells.

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This article reviews the progress of a personal endeavour to develop chromatography as a quantitative procedure for the determination of reaction stoichiometries and equilibrium constants governing protein interactions. As well as affording insight into an aspect of chromatography with which many protein chemists are unfamiliar, it shows the way in which minor adaptations of conventional chromatographic practices have rendered the technique one of the most powerful methods available for the characterization of interactions. That pathway towards quantification is followed from the introduction of frontal gel filtration for the study of protein self-association to the characterization of ligand binding by the biosensor variant of quantitative affinity chromatography.

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Conventional kinesin is a microtubule-based molecular motor involved in the transport of membranous and non-membranous cargoes. The kinesin holoenzyme exists as a heterotetramer, consisting of two heavy chain and two light chain subunits. It is thought that one function of the light chains is to interact with the cargo. Alternative splicing of kinesin light chain pre-mRNA has been observed in lower organisms, although evidence for alternative splicing of the human gene has not been reported. We have identified 19 variants of the human KNS2 gene (KLC1) that are generated by alternative splicing of downstream exons, but calculate that KNS2 has the potential to produce 285919 spliceforms. Corresponding spliceforms of the mouse KLC1 gene were also identified. The alternative exons are all located 3' of exon 12 and the novel spliceforms produce both alternative carboxy termini and alternative 3' untranslated regions. The observation of multiple light chain isoforms is consistent with their proposed role in specific cargo attachment.

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Background: Gestational trophoblastic disease is a fascinating group of pregnancy disorders characterised by abnormal proliferation of trophoblast, ranging from benign to malignant. Because the disease is uncommon, there is a need to formulate management with the assistance of collective information. Methodology: A review of available information from English written literature was undertaken especially data reported by registries around the world (Charing Cross Hospital in England, the North-western University and the New England area in the USA as well as our own experience in Queensland, Australia). Where possible, collated data from relevant studies were analysed to answer some of the questions posed in clinical practice, with reference to metastatic disease to liver and brain, twinning of molar gestation and coexisting fetus, and placental-site tumour. Results: We found that molar gestation can be classified according to its clinical presentation which influences the time taken to reach human chorionic gonadotropin (HCG) 'negativity' and the risk of persisting disease. Categorisation of risk is the basis for choice of chemotherapy to achieve good outcomes. Metastases to liver and brain remain problems in management; the development of 'new' metastases during chemotherapy is a very poor prognostic factor. In the variant of twinning with molar gestation and coexisting fetus, it is important to elucidate the fetal karyotype in planning management: a 69XXX fetus is not salvageable but a normal 46XX or 46XY fetus faces the prospect of early preterm delivery. The placental-site tumour is very rare; localised disease is curable by surgery; chemotherapy is less effective in disseminated disease. From collated worldwide data, the recurrence rate after one mole is 1.3% and after two or more is 20%. Reproductive outcome in subsequent pregnancies, even after multidrug chemotherapy, is not different from the general population. Because of the increased risk long-term of second tumours after multidrug chemotherapy a closer surveillance of these patients is necessary Conclusion: In general, the disease in its persisting or malignant form is 'a cancer model par excellence' because of an identifiable precursor condition, a reliable HCG marker, and sensitivity of the disease to cytotoxic drugs. With current management, retention of fertility is possible and normal reproductive outcome assured.

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Este artigo relata resultados de uma pesquisa que teve como objetivo investigar as representações sociais da infertilidade feminina, entre mulheres de diferentes estratos sociais. Foram entrevistadas 180 mulheres, com idade variando entre 18 e 40 anos, sendo 90 moradoras de bairros populares, e 90 moradoras de dois bairros considerados de classe-média. Cada grupo foi dividido em 3 subgrupos: a) 30 mulheres casadas, com pelo menos um filho biológico; b) 30 mulheres casadas há pelo menos 1 ano, sem filhos; c) 30 mulheres solteiras, sem filhos. Para a coleta de dados utilizou-se a técnica de associação livre, tendo como expressão geradora "mulher que não pode ter filhos", além de perguntas específicas sobre a temática de interesse. Os dados mostraram como principais elementos do campo representacional tristeza, incompleta, frustração, cobrança dos outros, solidão, pessoa inferior, adoção, busca de soluções e não é problema, confirmando a permanência da concepção da infertilidade como uma condição estigmatizante para a mulher.

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A diarreia é a segunda causa de mortalidade em <5 anos e é responsável pela diminuição da produtividade na população economicamente ativa. Dentre os agentes infecciosos envolvidos, seis patotipos diarreiogênicos de Escherichia coli (DEC) merecem destaque: E. coli enteropatogênica (EPEC), E.coli enteroinvasora (EIEC), E. coli enterotoxigênica (ETEC), E. coli enteroemorrágica ou produtora de toxina de Shiga (EHEC/STEC), E. coli enteroagregativa (EAEC) e E. coli de aderência difusa (DAEC). O objetivo deste estudo foi determinar a frequência dos patotipos de DEC e caracterizar fenotípica e genotipicamente EAEC, DAEC, aEPEC e E. coli chain-like adhesion (CLA) isolados de fezes indivíduos de todas as idades atendidos nas Unidades de Saúde do município de Vitória, ES, entre janeiro de 2008 e junho de 2011. Os isolados de E. coli foram submetidos à: (i) PCR para detecção dos genes eae, bfpA, aat, lt, st, ipaH, stx1 e stx2; (ii) hibridização de colônia com as sondas eae, aat e daaC; (iii) adesão em cultura de células HEp-2 para evidenciar padrão de aderência agregativa (AA), difusa (DA) e chain-like adhesion (CLA). PCR para detecção de genes de virulência foi realizado em isolados de EAEC, CLA, DAEC e aEPEC. Isolados de EAEC e CLA, foram submetidos a testes de formação de biofilme e de película. Foram obtidos 328 espécimes fecais e E. coli foi isolada de 85,7%. Os seguintes patotipos foram identificados: EAEC (18,3%), DAEC (11%), aEPEC (2,6%), ETEC (0,7%). CLA foi identificada em 4,9% e EIEC, tEPEC e STEC não foram detectados. Dos 60 isolados de EAEC (AA) (25% aat+ por PCR e 35% por hibridização), fímbrias de aderência agregativa foram evidenciadas em baixa frequência (aggA- 1,7%, aafA- 0%, agg3A- 11,7%, hdA- 8,3%). EAEC típica correspondeu a 31,7% dos isolados de EAEC (aggR+), e foram significantes nestas a formação de biofilme, escore 3+ de produção de película e presença dos genes aat, agg3A, hdA, aap, sat, pet, set1A e iucA. Todos os isolados CLA apresentaram o gene pet, 87,5%, foram aggR-, formaram película e nenhum produziu biofilme. Dentre dos 42 isolados de DAEC (DA), a sonda daaC detectou 52,4%. PCR evidenciou adesinas afa/Dr (daaD e afa) em 59,5% e adesina AIDA-I não foi encontrada, sugerindo que outras adesinas estejam envolvidas na adesão da DAEC. Isolados de DAEC afa/Dr + foram estatisticamente mais isolados de <5 anos. Em aEPEC, os genes da ilha de patogenicidade OI-122 pesquisados, nleE, efa1/lifA e paa foram evidenciados em 30% dos isolados, todos provenientes de <5 anos. Características de virulência de tEAEC e DAEC Afa/Dr sugerem que sejam subpopulações relacionadas com diarreia. CLA não parece ser variante de EAEC.

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In order to obtain evidence on the size of the impact of the Hong Kong/68 variant of influenza A2 virus on the population of São Paulo, Brazil, serum samples taken in 1967 before this variant appeared and during successive years after it appeared were examined for their antibody content. Haemagglutination-inhibition tests performed on a total of 2726 serum samples from adults showed a sharp decrease in 1969 of the proportion of sera without antibody to the Hong Kong/68 variant and a corresponding mercase in the proportion with high titres. It was concluded that about three-quarters of the adult population became infected at some time after the variant appeared, the majority in the first year of prevalence.

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Acute physical exercise is associated with increased oxygen consumption, which could result in an increased formation of reactive oxygen species (ROS). ROS can react with several organic structures, namely DNA, causing strand breaks and a variety of modified bases in DNA. Physical exercise training seems to decrease the incidence of oxidative stress-associated diseases, and is considered as a key component of a healthy lifestyle. This is a result of exercise-induced adaptation, which has been associated with the possible increase in antioxidant activity and in oxidative damage repair enzymes, leading to an improved physiological function and enhanced resistance to oxidative stress (Radak et al. 2008). Human 8-oxoguanine DNA glycosylase 1 (hOGG1) is involved in the base excision repair (BER) pathway and encodes an enzyme responsible for removing the most common product of oxidative damage in DNA, 8-hydroxyguanine (8-OH-G). The genetic polymorphism of hOGG1 at codon 326 results in a serine (Ser) to cysteine (Cys) amino acid substitution (Ser326Cys). It has been suggested that the carriers of at least one hOGG1Cys variant allele exhibit lower 8-OH-G excision activity than the wild-type (Wilson et al. 2011). The aim of this study was to investigate the possible influence of hOGG1 Ser326Cys polymorphism on DNA damage and repair activity in response to 16 weeks of combined physical exercise training, in thirty healthy Caucasian men. Comet assay was carried out using peripheral blood lymphocytes and enabled the evaluation of DNA damage, both strand breaks and FPG-sensitive sites, and DNA repair activity. Genotypes were determined by PCR-RFLP analysis. The subjects with Ser/Ser genotype were considered as wild-type group (n=20), Ser/Cys and Cys/Cys genotype were analyzed together as mutant group (n=10). Regarding differences between pre and post-training in the wild-type group, the results showed a significant decrease in DNA strand breaks (DNA SBs) (p=0.002) and also in FPG-sensitive sites (p=0.017). No significant differences were observed in weight (p=0.389) and in lipid peroxidation (MDA) (p=0.102). A significant increase in total antioxidant capacity (evaluated by ABTS) was observed (p=0.010). Regarding mutant group, the results showed a significant decrease in DNA SBs (p=0.008) and in weight (p=0.028). No significant differences were observed in FPG-sensitive sites (p=0.916), in ABTS (p=0.074) and in MDA (p=0.086). No significant changes in DNA repair activity were observed in both genotype groups. This preliminary study suggests the possibility of different responses in DNA damage to physical exercise training, considering the hOGG1 Ser326Cys polymorphism.

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A Hemocromatose Hereditária (HH) é uma doença autossómica recessiva caracterizada pela absorção excessiva de ferro a nível intestinal e sua acumulação em órgãos vitais, podendo originar cardiomiopatia, cirrose e carcinoma hepatocelular. O correspondente diagnóstico molecular é obtido pela associação com genótipos específicos no gene HFE (homozigotia para p.Cys282Tyr ou heterozigotia composta p.Cys282Tyr/p.His63Asp). Contudo, nos países do sul da Europa, cerca de um terço dos doentes com diagnóstico clínico de HH não apresenta os referidos genótipos. Para identificar a base molecular da HH não-clássica em Portugal usaram-se metodologias de pesquisa geral de variantes genéticas (SSCP e dHPLC), Next-Generation Sequencing (NGS) e sequenciação de Sanger, cobrindo seis genes relacionados com o metabolismo do ferro em 303 doentes. Identificaram-se 69 variantes diferentes e de vários tipos, por ex. missense, nonsense, de splicing, que perturbam a transcrição do gene ou a regulação da tradução do mRNA. Seguidamente, realizaram-se estudos in silico e in vitro para esclarecer o significado etiológico de algumas das novas variantes. Concluiu-se que a base molecular desta patologia é bastante heterogénea e que a NGS é uma ferramenta adequada para efetuar a análise simultânea dos vários genes num grande número de amostras. Contudo, o estabelecimento da relevância clínica de algumas variantes requer a realização de estudos funcionais.

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The portfolio generating the iTraxx EUR index is modeled by coupled Markov chains. Each of the industries of the portfolio evolves according to its own Markov transition matrix. Using a variant of the method of moments, the model parameters are estimated from a data set of Standard and Poor's. Swap spreads are evaluated by Monte-Carlo simulations. Along with an actuarially fair spread, at least squares spread is considered.

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A presente dissertação tem como objetivo efetuar a análise comparativa de soluções adotadas de reabilitação de pavimentos flexíveis que integram a rede rodoviária nacional. No âmbito desta análise apresenta-se o estado da arte respeitante à reabilitação de pavimentos flexíveis, nomeadamente: mecanismos de degradação, famílias de degradações, avaliação da capacidade de carga dos pavimentos, metodologia utilizada no dimensionamento do reforço de pavimentos, sendo também efetuada uma análise comparativa de técnicas de reforço de pavimentos e dos tratamentos antifendas. Neste contexto, apresenta-se um caso de estudo no qual é efetuada uma análise de três soluções possíveis para a reabilitação estrutural do pavimento do IC 20 entre Almada e a Costa de Caparica. É feita a descrição da solução projetada pela EP, SA patenteada em concurso público lançado em 2007, a qual é de certa forma inovadora ao nível do tratamento retardador da reflexão de fendas. Aquela solução técnica é constituída pela aplicação de grelhas de fibra de vidro e grelhas de fibra de carbono, seguidas da colocação de uma camada de desgaste em mistura betuminosa rugosa com betume modificado com baixa percentagem de borracha reciclada de pneus usados (BBr - BBB). Complementarmente, é efetuada a análise da solução do projeto de reabilitação do IC 20, patenteado pela Subconcessionária do Baixo Tejo, que contemplou a aplicação de misturas betuminosas rugosas com betume modificado com média percentagem de borracha reciclada de pneus usados (BBr - BBM). Para além da solução patenteada pela subconcessionária, é analisada a solução do projeto de alterações (variante) apresentado pelo agrupamento de empresas construtoras, que foi adotado na execução da obra realizada no IC 20. A intervenção de reabilitação estrutural contemplou a utilização de uma camada de ligação em AC 16 10/20 (MBAM) e uma camada de desgaste em mistura betuminosa rugosa com betume modificado com média percentagem de borracha reciclada de pneus usados (BBr - BBM). Adicionalmente à caracterização de diferentes soluções de reabilitação de pavimentos flexíveis adotados em Portugal, é efetuada uma análise comparativa dos custos de ciclo de vida (construção, manutenção e conservação) de cada tipo de solução de reabilitação.

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This chapter presents some of the issues with holonic manufacturing systems. It starts by presenting the current manufacturing scenario and trends and then provides some background information on the holonic concept and its application to manufacturing. The current limitations and future trends of manufacturing suggest more autonomous and distributed organisations for manufacturing systems; holonic manufacturing systems are proposed as a way to achieve such autonomy and decentralisation. After a brief literature survey a specific research work is presented to handle scheduling in holonic manufacturing systems. This work is based on task and resource holons that cooperate with each other based on a variant of the contract net protocol that allow the propagation of constraints between operations in the execution plan. The chapter ends by presenting some challenges and future opportunities of research.

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Objectives - The aim of this work was to study the interaction between genetic polymorphisms (single-nucleotide polymorphisms, SNPs) of pro- and anti-inflammatory cytokines and fat intake on the risk of developing Crohn's disease (CD) or modifying disease activity. Methods - Seven SNPs in interleukin 1 (IL1), tumor necrosis factor alpha (TNFalpha), lymphotoxin alpha (LTalpha), and IL6 genes were analyzed in 116 controls and 99 patients with CD. The type of fat intake was evaluated, and the interaction between SNPs and dietary fat in modulating disease activity was analyzed. Results - Individuals who were homozygous for the IL6-174G/C polymorphism had a six-fold higher risk for CD (odds ratio (OR)=6.1; 95% confidence interval (95% CI)=1.9-19.4), whereas the TT genotype on the TNFalpha-857C/T polymorphism was associated with more active disease (OR=10.4; 95% CI=1.1-94.1). A high intake of total, saturated, and monounsaturated fats, as well as a higher ratio of n-6/n-3 polyunsaturated fatty acid (PUFA), was associated with a more active phenotype (P<0.05). Furthermore, there was an interaction between dietary fat intake and SNPs, with a high intake of saturated and monounsaturated fats being associated with active disease, mainly in patients carrying the variant alleles of the 857 TNFalpha polymorphism (OR=6.0, 95% CI=1.4-26.2; OR=5.17; 95% CI=1.4-19.2, respectively) and the 174 IL6 polymorphism (OR=2.95; 95% CI=1.0-9.1; OR=3.21; 95% CI=1.0-10.4, respectively). Finally, low intake of n-3 PUFA and high n-6/n-3 PUFA ratio in patients with the TNFalpha 857 polymorphism were associated with higher disease activity (OR=3.6; 95% CI=1.0-13.0; OR=5.92; 95% CI=1.3-26.5, respectively). Conclusions - These results show that different types of fat may interact with cytokine genotype, modulating disease activity.