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Uma abordagem integrativa usando dados de interação proteína-proteína e estudos genéticos para priorizar genes e funções biológicas em transtorno de déficit de atenção e hiperatividade / An integrative approach using protein-protein interaction data and genetic studies to prioritize genes and biological functions in attention-deficit/hyperactivty disorderLeandro de Araujo Lima 22 July 2015 (has links)
O Transtorno de Déficit de Atenção e Hiperatividade (TDAH) é a doença do neurodesenvolvimento mais comum na infância, afetando cerca de 5,8% de crianças e adolescentes no mundo. Muitos estudos vêm tentando investigar a suscetibilidade genética em TDAH, mas sem muito sucesso. Este estudo teve como objetivo analisar variantes raras e comuns contribuindo para a arquitetura genética do TDAH. Foram gerados os primeiros dados de exoma de TDAH de 30 trios brasileiros em que o filho foi diagnosticado com TDAH esporádico. Foram analisados tanto variações de único nucleotídeo (ou SNVs, single-nucleotide variants) quanto variações de número de cópias (ou CNVs, copy-number variants), tanto nesses trios quanto em outros conjuntos de dados, incluindo uma amostra brasileira de 503 crianças/adolescentes controles, bem como resultados previamente publicados em quatro estudos com variação de número de cópias e uma meta-análise de estudos de associação ao longo do genoma. Tanto os trios quanto os controles fazem parte da Coorte de Escolares de Alto Risco para o desenvolvimento de Psicopatologia e Resiliência na Infância do Instituto Nacional de Psiquiatria do Desenvolvimento (INPD). Os resultados de trios brasileiros mostraram três padrões marcantes: casos com variações herdadas e somente SNVs de novo ou CNVs de novo, e casos somente com variações herdadas. Embora o tamanho amostral seja pequeno, pudemos ver que diferentes comorbidades são mais frequentes em casos somente com variações herdadas. Após explorarmos a composição de variações nos probandos brasileiros, foram selecionados genes recorrentes entre amostras do nosso estudo ou em bancos de dados públicos. Além disso, usando somente genes expressos no cérebro (amostras pós-mortem dos projetos Brain Atlas e Genotype-Tissue Expression), construímos uma rede de interação proteína-proteína \"in silico\" com interações físicas confirmadas por pelo menos duas fontes. Análises topológicas e funcionais dos genes da rede mostraram genes relacionados a sinapse, adesão celular, vias glutamatérgicas e serotonérgicas, o que confirma achados de trabalhos independentes na literatura indicando ainda novos genes e variantes genéticas nessas vias. / Attention-Deficit/Hyperactivity Disorder (ADHD) is the most common neuro-developmental disorder in children, affecting 5.8% of children and adolescents in the world. Many studies have attempted to investigate the genetic susceptibility of ADHD without much success. The present study aimed to analyze rare and common variants contributing to the genetic architecture of ADHD. We generated exome data from 30 Brazilian trios where the children were diagnosed with sporadic ADHD. We analyzed both single-nucleotide variants (SNVs) and copy-number variants (CNVs) in these trios and across multiple datasets, including a Brazilian sample of 503 children/adolescent controls from the High Risk Cohort Study for the Development of Childhood Psychiatric Disorders, and also previously published results of four CNV studies of ADHD involving children/adolescent Caucasian samples. The results from the Brazilian trios showed 3 major patterns: cases with inherited variations and de novo SNVs or de novo CNVs and cases with only inherited variations. Although the sample size is small, we could see that various comorbidities are more frequent in cases with only inherited variants. After exploring the rare variant composition in our 30 cases we selected genes with variations (SNVs or located in CNV regions) in our trio analysis that are recurrent in the families analyzed or in public data sets. Moreover, using only genes expressed in brain (post-mortem samples from Brain Atlas and The Genotype-Tissue Expression project), we constructed an in silico protein-protein interaction (PPI) network, with physical interactions confirmed by at least two sources. Topological and functional analyses of genes in this network uncovered genes related to synapse, cell adhesion, glutamatergic and serotoninergic pathways, both confirming findings of previous studies and capturing new genes and genetic variants in these pathways.
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Měření základních parametrů plynových filtrů / Measurement of basic parameters of gas filtersMedek, Pavel January 2010 (has links)
This master’s thesis deals with establishment of parameters of the PPI filter material using methods of image analysis. The first part is aimed at general methods used in practice, an overview of splitting into filter clasification and characterization of the PPI filter material. The second part represents an introduction to problems of machine vision. There are outlined basic methods of image processing. Last parts of the thesis study the method using detection of bright light levels. The measurement and interpretation of results is performed with the PPI material - types 10/6 and 10/12. For image processing is used the MATLAB program, version 7.0.1.
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Comparative analysis of the relationship between the producer and consumer price index of beef and chicken meat in South Africa from 1991to 2018Aphane, Thabang Rasehla January 2022 (has links)
Thesis (M.Sc. Agriculture (Agricultural Economics)) -- University of Limpopo, 2022 / Beef and chicken meat play a very crucial role in providing food to South African consumers. However, the rise of food prices in South Africa is viewed to curtail progress and drives consumers into debt and forgone opportunity to access food. Hence, it is of importance to understand the consumer price index (CPI) of meat and the disaggregate components of beef and chicken meat producer price indexes (PPI) as they give a clear insight into how individual commodities contribute to the general and food price inflation.
The study aimed to comparatively analyse the relationship between PPI beef and CPI meat as well as PPI chicken meat and CPI meat in South Africa from 1991 to 2018. The objectives of the study were to compare the indexes’ variability, correlation, and causality between the different PPI and CPI components. The objectives were analysed using the Coefficient of variation (CV), the Pearson coefficient correlation, the Granger causality test, and the Vector Error Correction model.
The CV findings highlight that PPI beef had high variability (65%) compared to CPI meat (56.7%), whereas PPI chicken meat had low variability (49.2%) compared to CPI meat(56.7%). There was evidence of a positive correlation (0.99) between PPI beef and CPI meat as well as PPI chicken meat and CPI meat using Pearson coefficient correlation. In addition, a long-run relationship was found between PPI beef and CPI meat as well as between PPI chicken meat and CPI meat by using the VEC model. Granger causality results indicated that there was a unidirectional relationship from PPI chicken meat to CPI meat, and independent relationships were found from PPI beef to CPI meat, CPI meat to PPI beef as well as CPI meat to PPI chicken meat.
Based on the findings, the study recommends that policymakers, through evaluation of monetary policies, should continue maintaining a specific inflation target range as that will assist in stabilising meat prices in the economy. At the same time, protect meat producers against input price inflation using instruments such as input subsidies, grants, and the provision of modern technologies. / National Research Foundation (NRF)
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Influência do contra-íon usado na eletrossíntese do polipirrol em sua resposta como biossensor eletroquímico após a imobilização da polifenol oxidase / Influence of counter-ion used in the electrosynthesis of polypyrrole in your response as electrochemical biosensors after polyphenol oxidase immobilizationBarioto, Valquiria da Cruz Rodrigues 16 July 2009 (has links)
Neste trabalho, foram fabricados biossensores amperométricos a partir do uso da polifenol oxidase (PFO), obtida do abacate como fonte enzimática, imobilizada em filmes de polipirrol (PPI) e que foram eletrossintetizados em meio de três diferentes eletrólitos de suporte (NaCl e NaClO4 e NaDDS). O método de imobilização enzimática foi o da adsorção, sendo a solução de enzima adicionada à solução com o pirrol e o eletrólito durante o processo de eletropolimerização. Os filmes de PPI/PFO foram caracterizados por técnicas eletroquímicas, principalmente por voltametria cíclica. A detecção de compostos fenólicos (catecol e pirogalol) foi realizada pela técnica de cronoamperometria após se variar a concentração do analito. A morfologia dos filmes foi estudada por microscopia de força atômica (AFM), sendo observado que a presença da enzima no filme polimérico assim como o uso de diferentes eletrólitos de suporte levou a diferenças na superfície dos filmes. Além disto, verificou-se que o biossensor construído a partir do uso do NaCl, apresentava uma resposta mais eficiente, ou seja, ele foi capaz de detectar catecol e pirogalol em um menor limite de detecção. / In this study amperometric biosensors were manufactured from the use of polyphenol oxidase (PPO) obtained from avocado as a source of enzyme immobilized in polypyrrole (PPY) films that were electrosynthesized with three different support electrolytes (NaCl, NaClO4 and NaDDS). The method of enzyme immobilization was the adsorption. The PPO was added in the solution containing pyrrole and electrolyte during electropolymerization. The PPY/PPO films were characterized by electrochemical techniques mainly by cyclic voltammetry. Detection of phenolic compounds (catechol and pyrogallol) was performed by the technique of chronoamperometry after varying the concentration of the analyte. The morphology of the films was studied by the atomic force microscopy (AFM) and observed that the presence of the enzyme in the polymer film and the use of different electrolytes support led to differences in the surface of films. However it was found that the biosensor constructed from the use of NaCl showed more efficient response and it was able to detect catechol and pyrogallol in a lower limit of detection.
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Estudos sobre a imobilização da polifenoloxidase em filmes de polipirrol/poli-3-metiltiofeno e uso destes filmes em biossensores amperométricos / Studies on the immobilization of polyphenoloxidase polypyrrole/poly-3-methylthiophene films and their use in amperometric biosensorsSousa, Lívia Maria de Castro 07 June 2013 (has links)
Nesta dissertação, foram estudados os métodos de síntese de filmes poliméricos como matrizes hospedeiras da enzima tirosinase vislumbrando o desenvolvimento de biossensores mais seletivos e duradouros na detecção de compostos fenólicos. Os polímeros utilizados e preparados por cronoamperometria em acetonitrila foram: polipirrol (PPI), polimetiltiofeno (PMET) e copolímero PPI-PMET. Os filmes PPI-PMET apresentaram características intermediárias às dos filmes PPI e PMET, conforme se verificaram em espectros na região do infravermelho (FTIR), voltametria cíclica e microscopia de força atômica (AFM), evidenciando, assim, a formação de uma nova matriz polimérica. O processo de superoxidação do filme PPI-PMET foi estudado visando a uma imobilização mais eficiente da enzima, quando se obteve uma condição na qual a superoxidação ocorre somente nas cadeias de PPI. Biossensores amperométricos foram preparados a partir do uso da tirosinase extraída do abacate como fonte enzimática por imobilização física e realizada de maneiras diferentes em filmes não superoxidados e superoxidados. Foi feita a otimização das respostas dos filmes variando-se o pH, potencial de trabalho, concentração da enzima e tempo de imobilização da enzima para a detecção de catecol. Os resultados indicaram que a superoxidação do PPI nos filmes PPI-PMET favoreceu a imobilização da enzima, embora não fosse tão eficiente quando se comparou aos filmes com o PPI não superoxidado. Contudo, os biossensores, em geral, apresentaram grande sensibilidade ao catecol, com um limite de detecção baixo, da ordem de 0,12 µmol/L. / The synthesis methods of polymer films as host matrices of the enzyme tyrosinase were studied in this dissertation. It was expected the development of selective and everlasting biosensors for the detection of phenolic compounds. The used polymers were prepared by chronoamperometry in acetonitrile as followed: polypyrrole (PPI), polymethylthiophene (PMET) and copolymer PPI-PMET. The PPI-PMET films showed intermediate characteristics as the PPI and PMET films, as observed in the infrared spectra (FTIR), cyclic voltammetry and atomic force microscopy (AFM), thus indicating the formation of a new polymeric matrix . The process of overoxidized of PPI-PMET film was studied in order to achieve a more efficient immobilization of the enzyme, whilst it was achieved a condition in which overoxidized occurs only in the PPI chain. Amperometric biosensors were prepared from the use of tyrosinase extracted from avocado as an enzyme source by physical immobilization and performed in different ways in both overoxidized and non-overoxidized films. It was performed the optimization of the responses of the films by varying pH, operacuonial potential, enzyme concentration and time in the enzyme immobilization for the detection of catechol. The results showed that the overoxidized PPI in the films PPI-PMET favored the immobilization of the enzyme, although not as efficient when compared to the films with nom overoxidized PPI. Neverthless, the catechol biosensors showed a high sensitivity with a low detection limit in the order of 0.12 µmol/L.
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Filmes de polipirrol como matrizes para a imobilização da polifenol oxidase e aplicação como biossensores amperométricos na análise de compostos fenólicos / Polypyrrole film as matrix for the immobilization of polyphenol oxidase and application as amperometric biosensors in the analysis of phenolicFerreira, Elys Raquel Andrade 14 December 2007 (has links)
Nesta dissertação, a polifenol oxidase (PFO) como extrato bruto de abacate (Persea americana) foi imobilizada em filmes de polipirrol (PPI) sintetizados eletroquimicamente utilizando o glutaraldeído (GA) como um agente de ligação entrecruzada. Os filmes PPI e PPI/PFO-GA foram caracterizados por eletroquímica, principalmente voltametria cíclica, sendo avaliadas a eletroatividade e a reversibilidade eletroquímica. A detecção de compostos fenólicos em soluções padrão foi feita por cronoamperometria, tendo um controle sobre a concentração dos compostos. O processo de transferência de massa foi monitorado com uma microbalança de cristal de quartzo eletroquímica. Os resultados indicaram uma boa reprodutibilidade das medidas na detecção dos compostos fenólicos. A estabilidade do biossensor em uma solução tampão manteve-se durante 27 dias, um resultado aceitável já que é encontrado na literatura um tempo de vida estável para sistemas semelhantes em tomo de 30 dias / In this dissertation, polyphenol oxidase (PPO) as crude extract of avocado (Persea americana) was immobilized on electrochemical1y synthesized polypyrrole (PPY) films using glutaraldehyde (GA) as a crosslinking agent. PPY and PPY/PPO-GA films were electrochemical1y characterized, mainly by cyclic voltametry, where electroactivity and electrochemical reversibility were evaluated. The detection of phenolic compounds in standard samples was made by chronoamperometry with a control over the compound concentration. The process of mass transfer was monitored with an electrochemical quartz crystal microbalance (EQCM). Our results indicated a good repeatability of the measurements for the detection of phenolic compounds. The stability of biosensor in a buffer solution has remained for 27 days, a result acceptable since it is found in the literature a time of life stable for similar systems around 30 days
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Sanctuary versus business culture : perspectives of service users and professional staff towards service user involvement at a UK hospiceFindlay, Helen January 2018 (has links)
AIM - To explore the perspectives of service users and professional staff towards service user involvement within the context of a changing cultural environment at a UK hospice. METHOD - Case study and thematic analysis including interviews with 16 staff including the CEO and 6 service users at a UK hospice. FINDINGS - Three overarching themes were identified: involvement and disempowerment in decision-making; belonging and alienation in a period of organisational change; struggle to maintain wellbeing and identity in a changing culture. A key finding is that service users receiving care from the hospice wanted their voices to be heard, valued and respected for their personal care and issues affecting the hospice. Service users did not consider it a burden to be asked for their views. They felt disempowered by a consultation process about organisational changes that appeared not to take their views on board. There is a need to consider whether a reliance on surveys for involving service users is sufficient or can become tokenistic. External social-political-economic pressures plus increasing privatisation of public services could influence the way that hospices operate in future. This could involve moving from a sanctuary to a business culture and potentially towards managerialism by adopting a regulatory rather than rights-based approach with an emphasis on increasing reach, measuring numbers and hitting targets. Service users being viewed as consumers with a focus on reablement/rehabilitation activities and less on psychosocial support could also serve to push hospices to start behaving more like hospitals. CONCLUSION - More qualitative research is needed to ensure the voices of service users living with a life-limiting illness are heard. The contributions they make towards co-production of services and research should also be heard and influence practice and policy. Service users should also be more involved in education and training of staff.
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Psychopathy: correlates of the MMPI-2-RF and the three-factor model of psychopathyHall, Katherine Achsah Lisa 01 August 2018 (has links)
Psychopathy is a personality disorder characterized by antisocial deviance in the context of interpersonal and emotional detachment. The study of psychopathy in non-forensic samples is an area of growing interest, but one that is limited by the fact that most large-scale epidemiological studies, which collect a wealth of data that could further elucidate the phenotypic correlates, constructs, assessments, and etiologic mechanisms in psychopathy, typically do not include direct assessment of psychopathy construct or measurements. However, if facets of psychopathy could be predicted from other measures, such as broadband inventories of normal personality that are often administered in large-scale investigations, data from college epidemiological studies could be brought to bear light on the study of psychopathy.
This study is two-fold in the investigation of psychopathy. First, the present study replicated the work of Sellbom and colleagues (2012) three-psychopathy scales derived from the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF). These scales were developed to assess psychopathy as conceptualized in the PPI-R and include Global Psychopathy (Py-T), Impulsive-Antisociality (Py-IA) and Fearless-Dominance (Py-FD). Second, the present study built upon the three-psychopathy scales by investigating psychopathy’s construct in relation to Cooke and Michie’s (2001) three-facto model. A sample of 151 participants from a Midwestern university were administrated the PPI-R and MMPI-2-RF. The MMPI-2-RF three scales and construct of psychopathy were evaluated using bivariate correlations. Results support previous studies, regarding the Py-T, Py-IA, and Py-FD scales and the three-factor model of psychopathy.
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The Development of Intrinsically Cell-Permeable Peptide Libraries Using mRNA DisplayAbrigo, Nicolas A 01 January 2019 (has links)
Peptides are emerging as promising therapeutics due to their inhibitory affinity towards protein-protein interactions (PPI). However, peptides have been limited mainly by their poor bio-stability and lack of cell permeability. Efforts to generate drug-like peptides have led to the development of macrocyclic peptides, which exhibit improved stability. Yet, most macrocyclic peptides still require the assistance of a cell penetrating peptide (CPP) for cellular entry.
High throughput technologies have been exceptional tools for the discovery of peptides to interrupt PPIs. This work details the recent advancements we have made to improve our high throughput technique, mRNA display, to yield more therapeutically relevant peptides to inhibit PPIs. Our advancements are focused on cell permeability, protease stability, and secondary structure for enhanced affinity.
Here we develop and optimize a cyclic CPP that can be included in future mRNA display libraries. We also tested the ability of our CPP to deliver an impermeable peptide cargo into cells. We rationally designed and tested linear and cyclic peptides to improve affinity to the BRCA1 protein. We used computational work to complement our experimental results for our CPPs and BRCA1 inhibitors. We examined peptides that arose from a library containing a mix of linear, monocyclic, and bicyclic peptides constructed using orthogonal cyclization chemistries. We rationally designed cyclic peptides and tested their affinity against Hsp70. We proposed a novel selection strategy to find optimal CPP motifs.
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Accurate and Reliable Cancer Classi cation Based on Pathway-Markers and Subnetwork-MarkersSu, Junjie 2010 December 1900 (has links)
Finding reliable gene markers for accurate disease classification is very challenging due to a number of reasons, including the small sample size of typical clinical data, high noise in gene expression measurements, and the heterogeneity across patients. In fact, gene markers identified in independent studies often do not coincide with each other, suggesting that many of the predicted markers may have no biological significance and may be simply artifacts of the analyzed dataset. To nd more reliable and reproducible diagnostic markers, several studies proposed to analyze the gene expression data at the level of groups of functionally related genes, such as pathways. Given a set of known pathways, these methods estimate the activity level of each pathway by summarizing the expression values of its member genes and using the pathway activities for classification. One practical problem of the pathway-based approach is the limited coverage of genes by currently known pathways. As a result, potentially important genes that play critical roles in cancer development may be excluded. In this thesis, we first propose a probabilistic model to infer pathway/subnetwork activities. After that, we developed a novel method for identifying reliable subnetwork markers in a human protein-protein interaction (PPI) network based on probabilistic inference of subnetwork activities. We tested the proposed methods based on two independent breast cancer datasets. The proposed method can efficiently find reliable subnetwork markers that outperform the gene-based and pathway-based markers in terms of discriminative power, reproducibility and classification performance. The identified subnetwork markers are highly enriched in common GO terms, and they can more accurately classify breast cancer metastasis compared to markers found by a previous method.
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