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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Aplicação de marcadores urinários no diagnóstico e prognóstico do câncer de próstata / The role of urinary markers in the diagnosis and prognosis of prostate cancer

Luiz Henrique de Andrade Araújo 18 November 2015 (has links)
INTRODUÇÃO: O diagnóstico do câncer de próstata é realizado através da dosagem do PSA sérico e da realização do toque retal. Qualquer alteração dem ambos indicam a necessidade de realização da biópsia de próstata guiado por ultrassom. Contudo, a grande maioria dos pacientes submetidos a biópsia não tem câncer e, portanto, são submetidos a biópsia desnecessariamente. Além disso, muitos casos diagnosticados não precisam ser tratados devido ao comportamento indolente da neoplasia. Portanto, há necessidade de ferramentas mais acuradas no diagnóstico e prognóstico do câncer de próstata e os marcadores urinários são instrumentos promissores na avaliação dessa neoplasia. OBJETIVO: Avaliar o perfil de expressão de 5 genes (MMP9, PSMA, GREB1, hk3, PCA3) na urina de pacientes portadores de câncer de próstata em comparação com pacientes sem a neoplasia e analisar se há relação com os fatores prognósticos pré e pós-tratamento. MATERIAL/MÉTODOS: O estudo constituiu na análise de 46 pacientes portadores de câncer de próstata e 28 pacientes sem suspeita da neoplasia (PSA<2,5ng/ml; TR normal; e sem fatores de risco). A urina dos pacientes foi colhida após massagem prostática, armazenada e analisada posteriormente a expressão gênica através de reação em cadeia da polimerase em tempo real. Além da análise do perfil de expressão gênica em relação aos casos sem neoplasia, foram avaliados os perfis de acordo com os fatores prognósticos, como: escore de Gleason, PSA, densidade do PSA, estadiamento clínico e porcentagem do fragmento envolvido na biópsia. Posteriormente, as expressões dos genes foram avaliadas de acordo com as características patológicas da peça operatória, como estadio patológico, escore de Gleason, volume tumoral, comprometimento de vesículas seminais e de linfonodos. RESULTADOS: Foi demonstrada uma superexpressão da MMP9 em 85,7% das amostras com câncer em relação ao grupo controle, com média de 6,4x maior. Os genes PSMA, GREB1, hK3 e PCA3 apresentaram um padrão mais heterogêneo, com tendência a subexpressão nos casos de câncer. Quando avaliados conjuntamente, pode-se evidenciar que a superexpressão simultânea da MMP9 e PSMA estava presente em 100% dos pacientes com PSA >= 10ng/ml (p=0,007) e a superexpressão da MMP9 e GREb1 estava presente em 66,7% dos pacientes com < 50% dos fragmentos positivos (p=0,036). Após avaliação anátomo-patológica, foi possível identificar superexpressão do GREB1 em casos pT2 em comparação com pT3 (p=0,031) e superexpressão do PCA3 em casos com volume tumoral maior (>= 11% x < 11%) (p=0,006). CONCLUSÕES: O estudo demonstrou que os marcadores urinários podem ser uma ferramenta útil no diagnóstico e prognóstico do câncer de próstata. Foi evidenciada a superexpressão da MMP9 nos casos de câncer em relação ao grupo controle. Além disso, a superexpressão da MMP9 e PSMA em conjunto pode estar relacionada a tumores com PSA mais alto e, portanto, com prognóstico mais desfavorável, enquanto que a superexpressão da MMP9 e GREb1 em conjunto pode estar relacionado a tumores de menor volume. Também foi possível correlacionar os genes urinários com os achados anátomo-patológicos, com GREb1 significativamente mais expresso em tumores confinados a próstata, enquanto PCA3 mais expresso em casos de maior volume tumoral / INTRODUCTION: Currently, prostate cancer diagnosis is performed through the measurement of serum PSA and digital rectal examination. Any alteration in one or both indicates the need for ultrasound-guided prostate biopsy. However, the vast majority of patients undergoing biopsy do not have cancer and therefore undergo unnecessary biopsies. Moreover, many prostate cancer cases do not need to be treated due to the indolent behavior. Therefore, more accurate methods for diagnosis and prognosis of prostate cancer are necessary and urinary markers are promising tools in the evaluation of prostate tumors. OBJECTIVES: To evaluate the expression profile of 5 genes (MMP9, PSMA, GREB1, hk3, PCA3) in urine of patients with prostate cancer compared with patients without cancer and to determine whether there is a relationship with the pre and post treatment prognostic factors. MATERIAL/METHODS: The study consisted of the analysis of 46 patients with prostate cancer and 28 patients without cancer (PSA < 2.5 ng/ml, normal DRE, and no risk factors). The urine of patients was collected after prostatic massage, stored and subsequently gene expression analyzed by real time polymerase chain reaction. Besides the analysis of gene expression compared to cases without cancer, the profiles according to prognostic factors were evaluated, like Gleason score, PSA, PSA density, clinical staging and percentage fragment involved in the biopsy. Subsequently, gene expressions were evaluated according to the pathological features, such as pathologic stage, Gleason score, involvement of lymph nodes and seminal vesicles. RESULTS: An over-expression of urinary MMP9 was demonstrated in 85.7% of the samples with cancer compared to non-cancer, with a mean of 6.4x. The PSMA, GREB1, hK3 and PCA3 genes showed a more heterogeneous pattern, with a tendency to under-expression in cancer. When considered together, it can be evidenced that the simultaneous over-expression of MMP9 and PSMA was present in 100% of patients with PSA >= 10ng/ml (p=0.036) and over-expression of MMP9 and GREb1 was present in 66.7% of patients < 50% positive fragments involved (p=0,036). After pathological evaluation were identified over-expression of GREB1 in pT2 cases compared to pT3 (p = 0.031), and over-expression of PCA3 in cases with greater tumor volume ( >= 11% x <11%) (p=0.006). CONCLUSIONS: The study showed that urinary markers can be a useful tool in the diagnosis and prognosis of prostate cancer. Overexpression of MMP9 was observed in cancer cases compared to control cases and can be helpful to avoid unnecessary prostate biopsies. Furthermore, overexpression of PSMA and MMP9 together may be related to higher PSA tumors and therefore more unfavorable prognosis, whereas overexpression of MMP9 and GREb1 together may be related to lower volume tumors. It was also possible to correlate urinary genes with pathologic findings with GREb1 significantly more expressed in tumors confined to the prostate, while PCA3 most expressed in cases of higher tumor volume
212

Avaliação da relação entre haplogrupo mitocondrial e ancestralidade genômica no desenvolvimento de insuficiência cardíaca em amostra brasileira / Assessment of the relationship between mitochondrial haplogroup and genomic ancestry in the development of heart failure in Brazilian sample

Mari Maki Síria Godoy Cardena 15 August 2013 (has links)
As doenças cardiovasculares lideram as causas de morte em vários países, inclusive no Brasil, sendo a insuficiência cardíaca (IC) uma das enfermidades mais frequentes. Estudos epidemiológicos e de genética têm demonstrado associações entre a origem étnica dos indivíduos e o desenvolvimento de diversas doenças cardiovasculares. O presente estudo teve como objetivo avaliar a relação entre haplogrupos mitocondriais e ancestralidade genômica no desenvolvimento da IC. Foram avaliados 503 pacientes com IC e 188 controles saudáveis. Os haplogrupos mitocondriais foram obtidos pela análise da região controle do DNA mitocondrial (mtDNA) e o estudo de ancestralidade genômica foi realizado pela análise de 48 marcadores autossômicos informativos de ancestralidade (AIMs) tipo INDEL. As análises estatísticas foram realizadas com o uso de regressão logística, construção de curvas de Kaplan-Meier e utilizando o método estatístico de log-rank (Mantel-Cox). Os resultados dos AIMs evidenciaram contribuições semelhantes de ancestralidade genômica entre os grupos de pacientes e controles, evidenciando a não estratificação populacional da amostra. A comparação dos haplogrupos mitocondriais entre os dois grupos revelou uma associação dos haplogrupos africanos com risco aumentado (p=0,015; OR 1,56) para o desenvolvimento da IC, enquanto que os haplogrupos ameríndios foi associado a um menor risco (p=0,043; OR 0,71). As análises realizadas apenas dentro do grupo de pacientes revelaram que 74,6% dos indivíduos se autodeclararam como brancos. As etiologias encontradas com maior frequência na nossa amostra foram a hipertensiva (28,6%) e a isquêmica (28,4%). A análise de mtDNA evidenciou que pacientes pertencentes aos haplogrupos africano apresentaram risco aumentado para o desenvolvimento da IC nas etiologias chagásica (p=0,012; OR 2,32) e hipertensiva (p=0,003; OR 2,05). Evidenciou também que pacientes dos haplogrupos africanos, principalmente da etiologia isquêmica, desenvolveram IC mais cedo que os demais, e que os pacientes com esses haplogrupos da etiologia valvar apresentaram maior sobrevida no período avaliado. A análise dos AIMs demonstrou que, na etiologia hipertensiva, a maior contribuição da ancestralidade genômica africana conferiu risco aumentado (p=0,002; OR 6,07), enquanto que a maior contribuição de ancestralidade genômica europeia conferiu risco diminuído (p=0,001; OR 0,16) para o desenvolvimento da IC; os pacientes com maior contribuição de ancestralidade genômica ameríndia apresentaram maior sobrevida no período de 4 anos. O uso de marcadores autossômicos e do DNA mitocondrial fornece estimativas mais precisas da ancestralidade de um indivíduo e/ou população, enquanto que a autodeclaração de cor de pele fornece indiretamente informações importantes sobre aspectos socioeconômicos e culturais. Assim, seria interessante a utilização, especialmente em populações miscigenadas, de uma construção tridimensional de análise, que poderia fornecer dados mais informativos e complementares em estudos de associação entre etnia e fenótipos e/ou doenças complexas / Cardiovascular diseases are the leading cause of death in many countries, including Brazil, being the heart failure (HF) one of the most common diseases. Epidemiological and genetic studies have shown associations between the ethnic origin of individuals and the development of various cardiovascular diseases. The aim of this study was to evaluate the relationship between mitochondrial haplogroups and genomic ancestry in the development of HF. We evaluated 503 patients with HF and 188 healthy controls. The mitochondrial haplogroups were obtained by analysing the control region of mitochondrial DNA (mtDNA) and the study of genomic ancestry was conducted by the analysis of 48 autosomal ancestry informative markers (AIMs) INDEL type. Statistical analyzes were performed using logistic regression, construction of the Kaplan-Meier and using the log-rank test (Mantel-Cox). The results of AIMs showed similar contributions of genomic ancestry among the patients and controls groups, indicating no population stratification of the sample. Comparing mitochondrial haplogroups between the groups, we observed that african haplogroups show increased risk (p=0.015, OR 1.56) of development of the HF, while ameridian haplogroup was associated with a reduced risk (p=0.043, OR 0.71). The analysis carried out only within the group of patients showed that 74.6% of individuals self-declared as white. The etiologies found with greater frequency in our sample were hypertension (28.6%) and ischemic (28.4%). Analysis of mtDNA showed that patients belonging to african haplogroup have increased risk of the development of HF in chagasic (p=0.012, OR 2.32) and hypertensive etiologies (p=0.003, OR 2.05). It also showed that patients of african haplogroups, specially of ischemic etiology, developed HF earlier than others, and the patients with this haplogroup of valvular etiology had better survival in the study period. AIMs analysis showed that in hypertensive etiology, the major contribution of african genomic ancestry conferred increased risk (p=0.002, OR 6.07), while the major contribution of european genomic ancestry conferred decreased risk (p=0.001, OR 0 16) to the development of HF; patients with higher contribution of amerindian genomic ancestry had better survival within 4 years. The use of autosomal markers and mtDNA provides more accurate estimates of ancestry of an individual and/or population, while the self-declared ethnicity, indirectly provides important information about socioeconomic and cultural aspects. Thus, it would be interesting to use, especially in admixed populations, the construction of a three-dimensional analysis, which could provide more informative and complementary data in studies of association between ethnicity and phenotypes and/or complex diseases
213

Polimorfismos no gene paraoxonase 1 como preditores de eventos cardiovasculares em pacientes com doença coronária estável / Paraoxonase1 gene polymorphisms as predictors of cardiovascular events in stable coronary artery disease

Letícia de Araujo Funari Ferri 15 January 2010 (has links)
Os polimorfismos do gene da paraoxonase 1 (PON1) estão relacionados ao metabolismo lipídico conferindo efeito marginal e modesto nas concentrações séricas das lipropoteínas e sobre o risco de desenvolvimento de doença arterial coronária (DAC). O objetivo primário deste estudo é avaliar se há associação entre os polimorfismos da PON1: R192Q- rs662, R160G: rs13306698, Leu55Met: rs854560, Promoter_161: rs705381 e rs3917464 e eventos cardiovasculares em 5 anos numa sub-população com DAC estável do estudo MASS II (Medical, Angioplasty or Surgery Study II). Como objetivos secundários, investigamos a influência destes polimorfismos nas concentrações lipídicas iniciais e após 5 anos de acompanhamento, e também a sua relação com os desfechos cardiovasculares combinados no grupo randomizado para tratamento clínico exclusivo. Foram randomizados 611 pacientes para o MASS II. A população alvo deste estudo foi constituída por 518 pacientes que tiveram material genético coletado (MASS II Genético). Os polimorfismos avaliados, apesar de estarem associados ao metabolismo do HDL-c, apresentaram baixa associação com os níveis lipídicos e com o seu comportamento ao longo de 5 anos. Houve diferença nas concentrações médias de HDL-c entre os genótipos do Promoter_161, o alelo T associado a concentrações mais baixas de HDL-c (p=0,0369). Análise univariada mostrou que houve associação entre o raro alelo G do polimorfismo R160G (5 pacientes) e aumento da mortalidade, porém quando incluído no modelo ajustado por regressão logística multivariada não se mostrou preditor independente de óbito nesta população. Na análise do grupo randomizado para o tratamento médico, o polimorfismo R192Q está associado de forma independente ao novo infarto agudo do miocárdio, óbito, e eventos combinados. Genótipo GG aumentou o risco de óbito em 7,69 vezes (IC: 1.65- 35.76) e de IAM em 6,58 vezes (IC: 1.39- 30.46) quando comparado ao genótipo AA. Alelo A estava independentemente associado a ocorrência de eventos cardiovasculares combinados com um OR de 3,03 (IC: 1.29- 7.07). Em conclusão, o nosso estudo mostrou associação do alelo G na posição R160G com risco aumentado de óbito em pacientes com DAC estável. Em pacientes mantidos no tratamento clínico a posição R192Q está associada ao maior risco de óbito, IAM e eventos cardiovasculares combinados. / Paraoxonase 1 (PON1) gene polymorphisms have a known relation with lipid metabolism, conferring a marginal and modest effect on serum lipoprotein concentrations and also on development of coronary artery disease (CAD). The primary objective of this study is to investigate the association between PON1 polymorphisms: R192Q- rs662, R160G: rs13306698, Leu55Met: rs854560, Promoter_161: rs705381, and rs3917464 and 5-year follow-up cardiovascular events in a subpopulation with stable CAD from MASS II (Medical, Angioplasty or Surgery Study II). Secondary objectives will be to evaluate the influence of these polymorphisms on baseline and 5-year follow-up lipid concentrations and also its association with combined cardiovascular events in the MASS II group randomized for medical treatment. MASS II had 611 patients randomized. Target population comprises 518 patients who had genetic material sampled. Even though the polymorphisms were linked to HDL-c metabolism, there was a low association with lipid levels and changes over the 5-year follow-up. HDL-c mean concentrations were different in the Promoter_161 genotypes, T-allele was associated with lower levels (p=0.0369). Univariate analysis showed association between the rare G-allele of polymorphism R160G (5 patients) and increased mortality, but when adjusted in the multivariate logistic regression model this variable was not independent predictor of mortality in this population. In the medical treatment group, r192Q is associated with new myocardium infarction (MI), combined events and death. When compared to AA genotype, GG genotype increased the risk of death by 7.69 (CI: 1.65- 35.76) and of MI by 6.58 (CI: 1.39- 30.46). A-allele is independently associated with combined cardiovascular events with a OR of 3.03 (CI: 1.29- 7.07). In conclusion, this study showed association between G-allele on R160G position with increased mortality in patients with stable CAD. R192Q polymorphism is associated with higher risk of death, MI and combined cardiovascular events in patients treated medically.
214

Estudo do polimorfismo genético C242T no gene da p22phox e a incidência de eventos cardiovasculares na doença arterial coronária / Identification of genetic markers with diagnosis and prognosis potential in coronary artery disease

Alexandre da Costa Pereira 09 May 2008 (has links)
O desenvolvimento de uma abordagem de estratificação de risco para a doença arterial coronária é certamente uma ferramenta de grande utilidade para o cardiologista clínico ou clínico geral, assim como para o planejamento de saúde pública e organização de ações de saúde pública mais eficazes. No entanto, esse conhecimento deve ser discutido dentro de um cenário de custo-efetividade e de acordo com seu potencial como objeto de valor econômico. O presente estudo tem como objetivo a identificação de fatores de risco genético de eventos cardiovasculares na população brasileira e o desenvolvimento de um algoritmo preditor que utilize essas informações para o diagnóstico. Esse trabalho encontra-se expositivamente dividido em dois módulos. No primeiro, procuramos exemplificar através de um estudo de associação genética nossa capacidade atual de encontrar e caracterizar variantes genéticas com poder de estratificação populacional com relação ao risco cardiovascular. Utilizamos dados obtidos a partir de pacientes com doença coronária multiarterial, analisando a relevância do polimorfismo C242T do gene da p22phox, subunidade protéica da NADPH oxidase, na predição de mortalidade desta população. Nossos dados permitem não apenas associar esse marcador genético a um risco aumentado de mortalidade nessa população, mas também fornecem informações a respeito do provável mecanismo molecular através do qual esse marcador genético age. No segundo módulo, procuramos detalhar as limitações da abordagem previamente exemplificada, avaliando a informação gerada para o paciente individual. Aqui propomos uma nova abordagem de estratificação de risco desta população, capaz de fornecer de maneira individualizada uma estimativa de risco com maior sensibilidade, especificidade e, conseqüentemente, acurácia. Através de uma abordagem analítica de redução de dimensionalidade obtivemos um algoritmo preditor com acurácia maior do que aquela encontrada utilizando-se apenas os fatores de risco clássicos ou fatores de risco genéticos analisados individualmente. O entendimento das bases genéticas do desenvolvimento de doenças cardiovasculares facilitará não apenas o diagnóstico precoce, possibilitando o surgimento de abordagens terapêuticas mais específicas e desenhadas a atender suscetibilidades individuais, mas também poderá levar à identificação de novas vias eficazes de intervenção. / The development of risk stratification approaches in coronary artery disease is certainly an important tool for the clinical cardiologist or internist. It also helps in the planning of public health policies and in the development of effective disease management algorithms. Nevertheless, these tools necessarily have to be developed in a cost-effective scenario and in close relationship with its intrinsic economic value. The present research project aims at the identification of genetic risk factors for cardiovascular events in the Brazilian population and the development of an algorithm with high predictive value for the diagnosis of these events. This thesis is, didactically, divided into 2 modules. Firstly, we have exemplified the used paradigm through the development of a genetic association study conducted in the Brazilian population. Here, we were able to describe and characterize genetic variants with the capacity of risk stratify populations into high and low risk groups. This section was possible with the use of data derived from patients with multi-vessel coronary artery disease and the analysis of the C242T gene variant of the p22phox gene, a subunit of the NADPH oxidase protein complex. Our data show not only a major signal of association between this genetic variant and overall mortality in this population, but also shed light on the potential molecular mechanism of this finding. Secondly, we have described the potential limitations of this approach analyzing information derived for the individual patient. Here, we propose a new risk stratification algorithm for this population with the capacity to provide individual risk with increased sensitivity and specificity. Through the use of a dimensionality reduction analytical approach we were able to find a predictive algorithm with higher accuracy than the one derived with the use of only classical cardiovascular risk factors and no genetic information. The understanding of the genetic basis for cardiovascular disease will improve not only the early diagnosis of these disorders, facilitating the rise of therapeutic approaches more specific and tailored to ones particular genetic susceptibility, but also lead to the identification of new pathways for effective intervention
215

Evaluation of the genetic diversity of Malawian pigeonpea using simple sequence repeats markers

Michael, Vincent Njung'e 20 August 2014 (has links)
Pigeonpea (Cajanus cajan (L.) Millsp.) is a drought tolerant legume of the Fabaceae family in the order Fabales and the only cultivated species in the genus Cajanus. It is mainly cultivated in the semi-arid tropics of Asia and Oceania, Africa and America. In Malawi, one of the top producers of pigeonpea in Africa, it is grown by small scale farmers as a source of food and income and for soil improvement in intercropping systems. However, varietal contamination due to natural outcrossing causes significant yield losses for farmers. In this study, 48 polymorphic SSR markers were used to assess diversity in all pigeonpea varieties cultivated in Malawi with the aim of developing a genetic fingerprint to distinguish the released varieties. SSR alleles were separated by capillary electrophoresis on an ABI 3700 automated sequencer and allele sizes determined using GeneMapper 4.0 software. Allelic data was analysed with PowerMarker. A total of 212 alleles were revealed averaging 5.58 alleles per marker with a maximum number of 14 alleles produced by CCttc019 (Marker 40). Polymorphic information content (PIC) ranged from 0.03 to 0.89 with an average of 0.30. DARwin software was used to generate a neighbour-joining tree that displayed three major clusters with two sub clusters in Cluster I. The released varieties were scattered across all the clusters observed, indicating that they generally represent the genetic diversity available in Malawi, although it was observed that there is substantial variation that can still be exploited through further breeding. Screening of the allelic data associated with five popular pigeonpea varieties for which a DNA fingerprint was to be developed, revealed 6 markers – CCB1 (Marker 1), CCB7 (Marker 2), Ccac035 (Marker 7), CCttc003 (Marker 15), Ccac026 (Marker 37) and CCttc019 (Marker 40)– which gave unique allelic profiles for each of the five varieties. With further tests needed for its robustness, this genetic fingerprint can be used for seed certification to ensure only genetically pure seeds are delivered to Malawi farmers. / Agriculture and  Animal Health / M. Sc. (Agriculture)
216

Analysis of a TNFRSF11A Gene Polymorphism and External Apical Root Resorption During Orthodontic Treatment

French, Michael 07 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / External Apical Root Resorption (EARR) can be an undesirable side effect of orthodontic treatment. Several studies have already recognized a genetic predisposition to EARR, and some have suggested possible candidate genes that may be involved. The objective of this prospective study was to explore one possible candidate gene that may predispose individuals to EARR during orthodontic treatment. The TNFRSF11A gene encodes the receptor activator of nuclear factor-kappa β (RANK). Together with the RANK ligand, RANK mediates cell signaling that leads to osteoclastogenesis. A diallelic marker was used to investigate the possible relationship between a nonsynonymous TNFRSF11A (RANK) polymorphism and the individuals' development of EARR concurrent with orthodontic treatment. Buccal swab cells of 112 patients who had completed orthodontic treatment were collected for DNA isolation and analysis. EARR of the maxillary central incisors was calculated based on measurements from pre and post treatment occlusal radiographs. Linear regression analysis indicated that length of treatment, overjet, and molar classification are significant predictors of EARR (p=0.05). Other factors, including age, gender, and overbite, were not found to be significantly associated with EARR. An ANOVA was performed to examine the relationship of the genotyped TNFRSF11A marker with the dependent variable EARR. When individuals having at least one copy of allele 2 (1,2 and 2,3 genotypes) were pooled together, a marginally significant association was found between EARR and the marker. Further analysis using logistic regression revealed that individuals with a (1,1) genotype are 4.3 times more likely to be affected by EARR than a person with a (1,2) or (2,2) genotype. From these findings it was concluded that EARR is a complex condition influenced by several treatment variables with the TNFRSF11A gene and its product (RANK) contributing to the individuals' predisposition.
217

Remodeling of three-dimensional organization of the nucleus during terminal keratinocyte differentiation in the epidermis

Gdula, M. R., Poterlowicz, K., Mardaryev, A. N., Sharov, A. A., Peng, Y., Fessing, M. Y., Botchkarev, V. A. January 2013 (has links)
The nucleus of epidermal keratinocytes (KCs) is a complex and highly compartmentalized organelle, whose structure is markedly changed during terminal differentiation and transition of the genome from a transcriptionally active state seen in the basal and spinous epidermal cells to a fully inactive state in the keratinized cells of the cornified layer. Here, using multicolor confocal microscopy, followed by computational image analysis and mathematical modeling, we demonstrate that in normal mouse footpad epidermis, transition of KCs from basal epidermal layer to the granular layer is accompanied by marked differences in nuclear architecture and microenvironment including the following: (i) decrease in the nuclear volume; (ii) decrease in expression of the markers of transcriptionally active chromatin; (iii) internalization and decrease in the number of nucleoli; (iv) increase in the number of pericentromeric heterochromatic clusters; and (v) increase in the frequency of associations between the pericentromeric clusters, chromosomal territory 3, and nucleoli. These data suggest a role for nucleoli and pericentromeric heterochromatin clusters as organizers of nuclear microenvironment required for proper execution of gene expression programs in differentiating KCs, and provide important background information for further analyses of alterations in the topological genome organization seen in pathological skin conditions, including disorders of epidermal differentiation and epidermal tumors.
218

Prenatalni ultrazvučni skrining drugog trimestra trudnoće u predikciji Daunovog sindroma / Prenatal ultrasound screening during second trimester of pregnancy in prediction of Down syndrome

Kolarski Milenko 26 August 2016 (has links)
<p>UVOD Prenatalna dijagnostika predstavlja skup metoda i postupaka čiji je cilj da potvrde ili isključe postojanje kongenitalnih anomalija ploda. Prenatalni skrining može biti ne invazivni i invazivni. Ne invazivni skrining treba da ima visku senzitivnost i da omogući adekvatnu selekciju trudnica kojima će se predložiti genetsko ispitivanje ploda iz uzoraka dobijenih invazivnim metodama prenatalne dijagnostike. Prenatalni skrining prvog trimestra trudnoće obuhvata ultrazvučni pregled debljine nuhalne translucencije i laboratorijsku analizu dva biohemijska markera od 11 do 14 nedelje trudnoće, Prenatalni skrining drugog trimestra trudnoće koji se zasniva na biohemijskom skriningu i tripl testu iako je jedini koji se primenjuje zbog niske senzitivnosti od 20% do 40%, ne može se smatrati validnim. Integrativni biohemijski test prvog i drugog trimestra imaj veću senzitivnost (od 40 do 60%) ali ni on nije dao očekivane rezultate u adekvatnoj selekciji trudnica za genetsku analizu ploda zbog visoke stope lažno pozitivnih rezultata. Drugi trimestar trudnoće omogućava sonografskim pregledima i biohemijskim analizama dopunski način a u nekim slučajevima i jedini u proceni postojanja rizika Daunovog sindroma ili nekih drugih hromozomskih aberacija ploda Zato je primena integrativnih prenatalnih ne invazivnih metoda prvog i drugog trimestra trudnoće veoma značaja u pobolj&scaron;anju dijagnostičkih vrednosti prenatalnih skrining testova i ima za cilj da smanji procenat invazivnih procedura zbog mogućih komplikacija i ne potrebnih finansijskih tro&scaron;kova. Daunov sindrom(trizomija 21 para hromozoma) je najče&scaron;ća hromozomska numerička aberacija praćena mentalnom retardacijom dece (I.Q&lt;70. ) Deca sa Daunovim sindromom su karakterističnog fenotipskog izgleda i sa čestim kongenitalnim anomailjama koje im onemogućavaju normalan život a često su i uzrok njihove prerane smrtnosti. Kongenitalne anomalije su zastupljene kod 2% do 5% živo rođene dece, predstavljaju 25 % perinatalne smrtnosti, četvrtina su uslovljnene hromozomskim aberacijama ili naslednom osnovom, od čega 0, 2%-0, 4% su sa Daunovim sindromom. CILJEVI Ciljevi četrorogodi&scaron;njeg istraživanja su bili da se pobolj&scaron;a dijagnostička vrednost postojećih prenatalnih testova, da se potvrdi značaj ultrazvučnog skrininga drugog trimestra trudnoće analizom debljine vratne brazde i dužine butne kosti ploda te da se pobolj&scaron;a njegova senzitivnost korporativnom sonografskom analizom cefaličnog indexa, intraorbitalnog rastojanja i dužine fronto-talamične distance. MATERIJAL I METODE Ukupan broj trudnica obuhvaćen četvorogodi&scaron;njim ispitivanjem koje su ultrazvučno pregledane i kojima je savetovano genetsko ispitivanje ploda blio je 4552. Tokom Retrospektivnog dvogodi&scaron;njieg ( 2010.2011)bila je 2169 dok je prospektivnom dvogodi&scaron;njom analizom (2012, 2013)je bilo obuhvaćeno 2383 trudnica. Ispitivana grupa su bile trudnice kod kojih je genetskom analizom otkriven patolo&scaron;ki kariotip ploda, kontrolna grupa je obuhvatila sve ostale trudnice kod je kariotip ploda bio normalan od kojih su 124 trudnice odabrane metodom slučajnog izbora. Retrospektivnom studijom ultrazvučna je pregledana dužina vratne brazde(&gt;6mm i dužina butne kosti&lt;0, 6 od 14 do 22 nedelje trudnoće. Analizirana je cirkulacija fetalne krvi kroz duktus venosus ploda( a talas) i postojanje nosne kosti ploda(+, -). Prospektivnom analizom je ultrazvučnim pregledom ploda dodatno analiziran cefalični index(&gt;85%), i intraorbitalna distanca i duzina fronto-talamične distance(&lt;80%) ploda. Kori&scaron;ćene su metode deskriptivne statističke analize, aritmetička sredina, standardna devijacija, najmanja i najveća vrednost kod parametrijskih obeležja dok su za ne parametrijska postojanje nosne kosti i alfa talasa duktusu venozusu kori&scaron;ćene druge statističke metode, a komparativnim statističkim metodama kod normalnih, patolo&scaron;kih i kariotipova sa Daunovim sindromom ploda. Statistička značajnost je dokazana t testom a definisana nivoom p&lt;0, 05 i p&lt;0, 001 odnosom kod normalnih, patolo&scaron;kih kariotipova i Daunovog sindroma. Multifaktorskom regresivnom logističkom analizom je urađena procena senzitvnosti prenatalnog ultrazvučnog skrininga sa ispitivanim obeležjima drugog trimestra trudnoće REZULTATI I DISKUSIJA Od ukupnog broja ultrazvučno pregledaninh trudnica 4552 kojima je savetovano genetska analiza ploda citogenetskom analizom je otkriveno 66 patolo&scaron;kih kariotipova 1, 49%, sa Dunovim sindromom 31 0, 68%. Deskriptivnom statističkom obradom ultrazvučno ispitivanih obeležja od 14 do 22 nedelje trudnoće, uočeno je odstupanje i potvrđen značaj starije životne dobi trudnica, debljine vratne brazde i dužine frontotalamične distance u odnosu na normalne nalaze katiotipova ploda u predikciji Daunovog sindroma.Vrednosti dužine butne kosti, cefaličnog indeksa i intraorbitalnog rastojanja nisu imala veća odstupanja u poređenju pato&scaron;kokih i normalnih nalaza kariotipova.Studentovim t testom je i dokazano p&lt;0, 001 za debljinu vratne brazde i dužinu fronto-talamične distance, dok je za stariju životnu dob trudnice potvrđeno a;0, 001. Senzitivnost prenatalnog skrininga drugog trimestra analizom debljine vratne brazde i dužine butne kosti je veća u odnosu na standardno primenjivan biohemijski skrining drugog trimestra tripl testa (senzitivnost 40%-60) sa velikom stopom lažno pozitivnih rezultata.Dokazan je značaj pobolj&scaron;anja senzitivnosti prenatalnih skrining testova dopunskom analizom tri ultrazvučna parametra, dužine fronto-talamične distance, cefaličnog indeksa i intraorbitalnog rastojanja u predikciji Daunovog sindroma, ali i kod ostalih hromozomskih aberacija ploda u periodu od 14 do 22 nedelje trudnoće primenomi multifaktorske logističke regresivne analize senzitivnost preko 93% sa 7% lažno pozitivnih rezultata. Postojanje korelacije između debljine vratne brazde i dužine fronto-talamične distance ploda pobolj&scaron;avai senzitivnost prenatalnih ultrazvučnog skrininga. Integrativnim pristupom ultrazvučnog i biohemijskog skrininga drugog trimesra trudnoće, tripl testa očekuje se pobolj&scaron;ati dijagnostičkih vrednosti prenatalnog skrininga senzitivnost ne invazivnog skrininga u predikciji Daunovog sindroma i ostalih hromozomskih aberacija ploda. ZAKLJUČCI 1Potvrđen je značaj starije životne dobi trudnice u povećanju rizika Daunovog sindoma, i ostalih hromozomskih aberacija ploda ( p&lt;0, 001) Potvrđen je značaj zadebljanja vratne brazde ploda &gt;6mm(p&lt;0, 001) i skraćenja butne kosti kod Daunovog sindroma ploda od 14 do 22 nedelje trudnoće u prenatalnom otkrivanju Dunovog sindroma i ostalih hromozomskih aberacija ploda i selekciji trudnica kojima će se predložiti genetsko ispitivanje ploda.Potvrđena je hipoteza da skraćenje fronto-talamične distance pobolj&scaron;ava senzitivnost ultrasonografskog skrininga, jer če&scaron;će postoji kod Daunovog sindroma ploda ali i ostalih numeričkih hromozomskih aberacija tipa, nego kod normalnih nalaza kariotipa ploda( p&lt;0, 001).Komparativnom analzom ultrazvučnim pregledom fronto-talamična distance debljine vratne brazde i dužine butne kosti ploda od 14 do 22 nedelje trudnoće može se značajno pobolj&scaron;ati vrednost dijagnostičkih prenatalnih testova u predikciji Daunovog sindroma. Postojanje korelacija između fronto-talamične distance i debljine vratne brazde dopunjuje ultrazvučni skrining i povećava njegovu senzitivnost na preko 90%, &scaron;to je multifaktorskom regresivnom logaritamskom analizom i potvrđeno. Značaj multidisciplinarnog pristupa pogotovo je izražen u predikciji Daunovog sindroma, obzirom na različite specijalnosti koje u njemu učestvuju. Cost &ndash; benefit analiza. Visoka senzitivnost ne invazivnog prenatalnog skrininga u predikciji Daunovog sindroma, smanjuje tro&scaron;kove za pojedince i državu jer je njihova cena i do dest puta manja od cene citogenetskih analiza, a i trudnice se ne izlažu riziku mogućih komplikacija prilikom izvođenja invazivnih metoda</p> / <p>INTRODUCTIONS Prenatal diagnostic procedure represent a set of methods and techniques with the aim to afirmate or eliminate the presence of Down&rsquo;s syndrome and other congenital anomalies Can be non-invasive and invasive methods. Non-invasive methods (laboratory or ultrasonographic) have the aim to make possible the most valid assessment of the risk of presence of an affected fetus in the pregnancy, selected pregnancy for invasive diagnostics procedures and citogenetics analisseskariotipingfoeti. Down&rsquo;s syndrome, aneuploidy with trisomy 21 chromosomal, is the most common chromosomal numerical aberration associated with mental retardation of children (IQ&lt; 70). Children with Down&rsquo;s syndrome have characteristic phenotypic appearance with high frequent congenital anomalies that preclude a normal life and are frequently the cause of their earlier death. AIM The aim of the four year long investigation was to confirm the importance of ultrasound screening by the analyses of the basic ultrasound parameters for the second trimester, the thickness of the nuchal fold and the length of the femur of the fetus in the prediction of Down&rsquo;s syndrome and other chromosomal aberrations of the fetus, as well as to improve other existing ultrasonic screenings of the first and second trimester of pregnancy by ultrasonic examination and analyses of the cephalic index and intraorbital space and the length of the fronto-thalamic distance. MATERIAL AND METODS Retrospective investigation (2010. 2011) and prospective investigation (2012.2013) includes 4655 pregnant women. For all pregnant women the genetic investigation of the fetus was performed. A total of 68 were found with chromosomal aberrations, 38 with Down&rsquo;s syndrome. The method of haphazard choice in retrospective study and in prospective study ultrasound markers are examined. In retrospective analyses of the nuchal fold (&lt;6mm and the length of femur &lt;0.6, that represent basic ultrasound screening of the second trimester and are analyzed as parametric signs of the second trimester, and are analyzed as parametric markers, and analyses of the circulation of fetal blood through ductus venosus of the fetus. In the retrospective study the length of the nuchal fold (&gt;6mm in length, that represent a basic ultrasound screening of the second trimester, and are analyzed as parametric markers in the prediction of Down&rsquo;s syndrome and other chromosomal aberrations. RESULTS AND DISCUSION Cytogenetic analyses revealed 66 (1, 49%) pathologic karyotypes and Down syndrome were present in 31 (0, 68%) cases. All pathologic karyotypes were obtained after ultrasound examinations of 4552 pregnant women. Ultrasound markers for period 14th-22nd GW were analyzed with descriptive statistical methods and importance of pregnancy in older women, thickness of nuchal fold and lengths frontal thalamic distance were proofed in case of Down syndrome. Femoral bone lengths, cephalic index and intraorbital distances were similar for both groups, normal and pathologic karyotypes. Student&rsquo;s t test revealed statistical significance with p&lt;0, 001 values for nuchal fold thickness, frontal thalamic distance and older ages.Three additional ultrasound markers (frontal thalamic distance, cephalic index, intraorbital distance) improve prediction of Down syndrome and other chromosomal aberrations between 14th and 22nd GW as well. Multifactorial logistic regressive analyses revealed 93% sensitivity with 7% false positive results. Corelation between nuchal fold thickness and frontal thalamic distance improve prenatal ultrasound screening sensitivity. Using both ultrasound and biochemical screening (triple test) is way to improve sensitivity of non invasive screening in prediction of Down syndrome and other chromosomal aberrations. CONCLUSIONS Importance of pregnant women ages and higher risk for Down syndrome and other chromosomal aberrations was proofed (p&lt;0, 001).Importance of nuchal fold thickness above 6mm (p&lt;0, 001) and shorter femoral bone marker in period from 14th to 22nd GW in prediction of Down syndrome and other chromosomal aberrations are proofed (p&lt;0, 001). Hypothesses that frontal thalamic distance improve ultrasound screening sensitivity was proofed was proofed (p&lt;0, 001) since it is significantly shorter in Down syndrome and other chromosomal aberrations in comparison with fetuses with normal karyotypes. Comparative analyses of frontothalamic distance, nuchal fold thickness and femoral bone length in period from 14th to 22nd GW can signifi cantly improve prenatal diagnostic testing in Down syndrome prediction. Correlation between frontothalamic distance and nuchal fold thickness improve ultrasound screening sensitivity on 93% that is proofed with multifactorial logistic regressive analyses. Significance of multidisciplinary approach is high in Down syndrome prediction. Cost-benefit: High sensitivity of non invasive prenatal screening in Down syndrome prediction reduces costs for families and government since it costs ten time less than cytogenetic analyses and risk with invasive procedures is avoided.</p>
219

Fatores genéticos associados ao clareamento espontâneo e resposta ao tratamento da infecção pelo vírus da hepatite C / Genetic factors associated with spontaneous clearance and response to treatment of hepatitis C infection

Nastri, Ana Catharina de Seixas Santos 17 October 2016 (has links)
O vírus da hepatite C (HCV) é uma importante causa de doença hepática crônica e de complicações associadas, tais como cirrose e hepatocarcinoma (HCC). Fatores virais e do hospedeiro são conhecidos preditores da terapia antiviral. Fatores do hospedeiro preditores da resposta viral sustentada (RVS) foram descobertos por estudos de associação genômica ampla (GWAS), correspondendo a polimorfismos de nucleotídeo único (SNPs) nos genes IFNL3 e IFNL4 (rs8099917, rs12979860 e rs368234815). O objetivo do presente trabalho foi verificar as frequências genotípicas dos SNPs rs8099917, rs12979860 e rs368234815 e avaliar a associação entre estes SNPs e a evolução clínica e a resposta ao tratamento da infecção pelo HCV tendo em conta a ancestralidade genética da população estudada. Neste estudo, foi observada a associação dos três polimorfismos tanto com o desfecho clínico quanto com a resposta ao tratamento com interferon peguilado (PEG-IFN) e ribavirina (RBV). Os polimorfismos rs12979860 e rs368234815 foram associados com aumento da sensibilidade (respectivamente 97,7%, IC 95% 87,2-100, e 93,3%, IC 95% 81,3-98,3) e com um maior valor preditivo de uma resposta positiva ao tratamento. Na análise multivariada ajustada por sexo, idade e ancestralidade genética, o haplótipo G/T/?G foi relacionado com a não-resposta ao tratamento (OR = 21,09, IC 95% 5,33-83,51; p < 0,001) e com uma chance maior de desenvolver infecção crônica (OR = 5,46, IC 95% 2,06-14,46; p=0,001), quando comparado com haplótipo T/C/TT. Estes resultados podem ajudar a ajustar políticas de tratamento para a infecção por HCV em populações com tais características genéticas, assim como nos permitem conhecer o perfil genético da nossa população em relação a esses polimorfismos / Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and associated complications such as liver cirrhosis and hepatocellular carcinoma (HCC). Viral and host factors are known to be predictors for anti-viral therapy. Host factors predictors of sustained viral response (SVR) were discovered by Genome-Wide Association Studies (GWAS), including single nucleotide polymorphisms (SNPs) near or on genes IFNL3 and IFNL4 (rs8099917, rs12979860 and rs368234815). The aim of the present work was verify the genotype frequencies of SNPs rs8099917, rs12979860 and rs368234815, and evaluate the association between these SNPs and HCV infection outcome taking into account the genetic ancestry of the population. In this study, there was an association of the three polymorphisms with both clinical outcome and response to treatment with pegylated interferon (PEG-IFN) and ribavirin (RBV). The polymorphisms rs12979860 and rs368234815 showed increased sensitivity (97.7%, 95% CI 87.2-100, and 93.3%, 95% CI 81.3-98.3 respectively) and greater predictive value of a positive response to treatment. In multivariable analysis adjusted by gender, age and genetic ancestry, the haplotype G/T/?G was related to non-response to treatment (OR = 21.09, 95% CI 5.33-83.51; p < 0.001) and to a higher chance to develop chronic infection (OR = 5.46, 95% CI 2.06-14.46; p=0.001) when compared to haplotype T/C/TT. These findings may help to adjust our treatment policies for HCV infection in populations with such genetic characteristics, as well as allowing us to get to know the genetic profile of our population for these polymorphisms
220

DNA strand breaks in crustaceans as an indicator of marine pollution.

January 2005 (has links)
Chan Kwan-ling. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 91-105). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.v / Contents --- p.vi / List of figures and tables --- p.ix / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Literature review --- p.1 / Chapter 1.1.1 --- The effect of pollutants on the genetic materials of aquatic organisms --- p.1 / Chapter 1.1.1.1 --- Response of individual to genotoxicants --- p.1 / Chapter 1.1.1.2 --- Effects of genotoxicants on population structure --- p.3 / Chapter 1.1.2 --- Application of genetic markers in monitoring water pollution --- p.3 / Chapter 1.1.2.1 --- DNA adduct --- p.4 / Chapter 1.1.2.2 --- Sister chromatid exchange (SCE) test --- p.5 / Chapter 1.1.2.3 --- Micronucleus --- p.6 / Chapter 1.1.2.4 --- DNA strand breaks --- p.7 / Chapter 1.1.3 --- Single-cell gel electrophoresis (comet) assay --- p.9 / Chapter 1.1.4 --- Test organisms for comet assay --- p.12 / Chapter 1.2 --- Objective of the present study --- p.13 / Chapter Chapter 2 --- Genotoxicity of pollutants on Hyale crassicornis / Chapter 2.1 --- Introduction --- p.22 / Chapter 2.2 --- Materials and methods --- p.24 / Chapter 2.2.1 --- Sampling of amphipods --- p.24 / Chapter 2.2.2 --- Acclimation --- p.24 / Chapter 2.2.3 --- Acute toxicity test --- p.26 / Chapter 2.2.4 --- The effect of test duration on DNA damage --- p.27 / Chapter 2.2.5 --- Effect of toxicants on DNA damage --- p.28 / Chapter 2.2.6 --- Comet assay --- p.29 / Chapter 2.2.7 --- Chemicals --- p.34 / Chapter 2.2.8 --- Data analysis --- p.34 / Chapter 2.3 --- Results --- p.34 / Chapter 2.4 --- Discussion --- p.47 / Chapter Chapter 3 --- Genotoxicity of hydrogen peroxide on different tissue types of Metapenaeus ensis / Chapter 3.1 --- Introduction --- p.54 / Chapter 3.2 --- Materials and Methods --- p.57 / Chapter 3.2.1 --- Collection and acclimation of shrimps --- p.57 / Chapter 3.2.2 --- Incubation --- p.59 / Chapter 3.2.3 --- Comet Assay --- p.60 / Chapter 3.2.4 --- Chemicals --- p.61 / Chapter 3.2.5 --- Data analysis --- p.61 / Chapter 3.3 --- Results --- p.61 / Chapter 3.4 --- Discussion --- p.67 / Chapter Chapter 4 --- Genotoxicity of wastewater on Hyale crassicornis / Chapter 4.1 --- Introduction --- p.71 / Chapter 4.2 --- Materials and Methods --- p.72 / Chapter 4.2.1 --- Collection of wastewater samples --- p.72 / Chapter 4.2.2 --- Metal content analysis --- p.73 / Chapter 4.2.3 --- Genotoxic effect of wastewater samples on Hyale crassicornis --- p.74 / Chapter 4.2.4 --- Chemicals --- p.76 / Chapter 4.2.5 --- Statistical analysis --- p.77 / Chapter 4.3 --- Results --- p.77 / Chapter 4.3.1 --- Metals content in water samples --- p.77 / Chapter 4.3.2 --- DNA damage --- p.79 / Chapter 4.4 --- Discussion --- p.79 / Chapter Chapter 5 --- Conclusions --- p.89 / References --- p.91

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