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A retrospective analysis of comorbid traits affecting feeding in infants with Down syndromeDuvall, Nichole L. 03 July 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Down syndrome (DS) is the most common aneuploidy to affect humans and occurs in approximately 1 of 750 live births. Individuals with DS present with a wide range of clinical phenotypes. Common craniofacial phenotypic expressions include a small mandible, protruding tongue, and a flattened nasal bridge. These traits may affect the feeding, breathing, and swallowing of individuals with DS. Because some complications may go unnoticed for longer periods of time, we hypothesize that significant cardiac and GI defects may be indicative of feeding and airway difficulties. In order to better understand the secondary phenotypes resulting from DS, we have implemented a retrospective chart review of 137 infants between zero and six months of age who were evaluated through the Down Syndrome Program at Riley Hospital for Children from August 2005 to August 2008. Data regarding cardiac, gastrointestinal, endocrine, airway, auditory, and feeding abnormalities have been collected and incedences and comorbidites of these traits has been examined. Comprehensive results indicate cardiac abnormalities occur in 80% of infants, 60% experience gastrointestinal complications, feeding difficulties occur in 46%, and airway complications occur in 38% of infants. Infants with DS were found to be breastfed less over time, with an increase in tube feeds. Notably, we have found all infants with videofluoroscopic evaluations had some type of dysphagia. The presence of gastrointestinal abnormalities closely correlate with the need for tube feeds, and the comorbidity between GI anomalies and muscle tone appear to indicate the likelihood of feeding difficulties and need for altered feeding strategies. Comorbidities between feeding difficulties were nearly significant with cardiac defects and significant with GI abnormalities. Identification of such associations will help healthcare providers determine the best course of treatment and recommended feeding methodology for infants with DS.
In order to utilize an in vitro model to study the craniofacial dysmorphologies seen in individuals with DS, cranial neural crest cells (NC) have been cultured. With these, we have begun to investigate the mechanisms behind a smaller trisomic mandibular precursor as compared to the euploid. With this in vitro model, we will be able to test proliferation, migration, and senescence of NC in a culture system.
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Family Environment, Social Support, and Psychological Distress of Women Seeking BRCA1 and BRCA2 Genetic Mutation TestingKeenan, Lisa A. 08 1900 (has links)
Shared characteristics and predictors of psychological distress are beginning to be identified in research on women seeking genetic testing for BRCA1 and BRCA2 gene mutations. This study further explored patterns of psychological distress for 51 community women waiting to receive such genetic test results. There was no significant relationship between psychological distress and family cancer history, personal cancer history, social support networks, and family environment. Women in this sample tended to rely more on females and relatives for support than males and friends. Social support satisfaction was not related to gender or number of relatives providing support. Thirty-four of the 36 women classified on the family environment type were from Personal Growth-Oriented families. Comparisons with normal and distressed family means revealed increased cohesion and expressiveness with decreased conflict, indicative of supportive family environments. Limitations and implications are discussed.
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Estudi de les anomalies cromosòmiques detectades prenatalment i postnatalment per mètodes citogenètics i anàlisi de la contribució dels diferents mètodes de cribratge en la detecció de les anomalies prenatals. Hospital Universitari Dr. Josep Trueta, període 1999-2009Alsius Suñer, Mercè 28 September 2012 (has links)
Chromosome abnormalities are one of the most important causes of congenital disorders. The main goal of this research is to give a broad view of the use and evolution of prenatal and postnatal cytogenetic diagnosis in Girona province between 1999 and 2009. It also aims at linking prenatal cytogenetic diagnosis with the existing screening methods.
The main conclusions are the following:
- A rise in the use of cytogenetic diagnosis has been detected. This has been caused by a growing preventive medicine trend.
- Case studies match the literature consulted when the study population is similar in accordance with national health policies.
- The overall sensitivity of obstetric ultrasound scan was 60,8%, and this result matches, and in many cases exceeds, those found in the literature consulted.
- The moving from second-trimester to first-trimester aneuploidy prenatal screening has meant a significant increase in aneuploidy detections.
- Prenatal cytogenetic diagnosis appears as an interdisciplinary field in which the extent of prenatal screening tests, like obstetric ultrasound scans and aneuploidy screening, is crucial. / Les anomalies cromosòmiques són una de les causes més importants dels defectes congènits. L’objectiu d’aquest treball és donar una visió global de l’ús i l’evolució del diagnòstic citogenètic prenatal i postnatal a les comarques de Girona en el període 1999-2009 i relacionar el diagnòstic citogenètic prenatal amb els diferents mètodes de cribratge.
Les conclusions principals són:
- Es constata un augment de l’ús del diagnòstic citogenètic com a resultat d’una tendència creixent en medicina preventiva.
- La casuística coincideix amb la bibliografia consultada quan la població d’estudi és semblant, atenent a la política sanitària del país.
- La sensibilitat global de l’ecografia obstètrica va ser del 60,8%, i és un resultat concordant i en molts casos millor en comparació amb la literatura consultada.
- La substitució del cribratge del segon trimestre pel cribratge del primer trimestre ha suposat un increment important en la detecció d’aneuploïdies.
- El diagnòstic citogenètic prenatal es mostra com a una àrea interdisciplinària en què la contribució de les proves de cribratge prenatal com l’ecografia obstètrica i el cribratge d’aneuploïdies són importants.
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Effect of Epigallocatechin-3-gallate on Skeletal and Cognitive Phenotypes in a Down Syndrome Mouse ModelAbeysekera, Irushi Shamalka January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Down syndrome (DS), a genetic disorder that affects ~1 in 700 live births, is caused by trisomy of human chromosome 21 (Hsa21). Individuals with DS are affected by a wide spectrum of phenotypes which vary in severity and penetrance. However, cognitive and skeletal impairments can be commonly observed in all individuals with DS. To study these phenotypes, we utilized the Ts65Dn mouse model that carries three copies of approximately half the gene orthologs found on Hsa21 and exhibit similar phenotypes as observed in humans with DS. Individuals with DS and Ts65Dn mice have deficits in bone mineral density (BMD), bone architecture, bone strength, learning and memory. Over-expression of DYRK1A, a serine-threonine kinase encoded on Hsa21, has been linked to deficiencies in DS bone homeostasis and cognition. Epigallocatechin-3-gallate (EGCG), an aromatic polyphenol found in high concentrations in green tea, is a selective inhibitor of DYRK1A activity. Normalization of DYRK1A activity by EGCG therefore may have the potential to ameliorate skeletal and cognitive deficits. We hypothesized that supplements containing EGCG obtained from health food stores/ online vendors will not be as effective as EGCG from a chemical company in correcting bone deficits associated
with DS. Our results suggest that EGCG improves the bone mineral density of trisomic femurs significantly better than the supplements while the EGCgNOW supplement from NOW FOODS improves trabecular and cortical bone structure. The results from HPLC analysis of supplements showed the presence of other catechins in EGCgNOW and degradation analysis revealed the rapid degradation of supplements. Therefore we hypothesize that the presence of EGCG degradation products and other green tea catechins in supplements may play a role in the differential skeletal effects we observed. We further hypothesized that a three week treatment of adolescent mice with EGCG will lead to an improvement in the learning and memory deficits that are observed in trisomic animals in comparison to control mice. However, our results indicate that three weeks of low-dose EGCG treatment during adolescence is insufficient to improve hippocampal dependent learning and memory deficits of Ts65Dn mice. The possibility remains that a higher dose of EGCG that begins at three weeks but lasts throughout the behavioral test period may result in improvement in learning and memory deficit of Ts65Dn mice.
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The Molecular Mechanism of Break Induced ReplicationAyyar, Sandeep 14 February 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / DNA double strand break (DSB) is one of the most threatening of all types of DNA damages as it leads to a complete breakage of the chromosome. The cell has evolved several mechanisms to repair DSBs, one of which is break-induced replication (BIR). BIR repair of DSBs occurs through invasion of one end of the broken chromosome into a homologous template followed by processive replication of DNA from the donor molecule. BIR is a key cellular process and is implicated in the restart of collapsed replication forks and several chromosomal instabilities. Recently, our lab demonstrated that the fidelity of DNA synthesis associated with BIR in yeast Saccharomyces Cerevisiae is extremely low. The level of frameshift mutations associated with BIR is 1000-fold higher as compared to normal DNA replication. This work demonstrates that BIR stimulates base substitution mutations, which comprise 90% of all point mutations, making them 400-1400 times more frequent than during S-phase DNA replication. We show that DNA Polymerase δ proofreading corrects many of the base substitutions in BIR. Further, we demonstrate that Pif1, a 5’-3’ DNA helicase, is responsible for making BIR efficient and also highly mutagenic. Pif1p is responsible for the majority of BIR mutagenesis not only close to the DSB site, where BIR is less stable but also at chromosomal regions far away from the DSB break site, where BIR is fast, processive and stable.
This work further reveals that, at positions close to the DSB, BIR mutagenesis in the absence of Pif1 depends on Rev3, the catalytic subunit of translesion DNA Polymerase ζ. We observe that mutations promoted by Pol ζ are often complex and propose that they are generated by a Pol ζ- led template switching mechanism. These complex mutations were also found to be frequently associated with gross chromosomal rearrangements. Finally we demonstrate that BIR is carried out by unusual conservative mode of DNA synthesis. Based on this study, we speculate that the unusual mode of DNA synthesis associated with BIR leads to various kinds of genomic instability including mutations and chromosomal rearrangements.
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Avaliação do risco de malformação congênita em recém-nascidos de mães expostas ao trihalometano / Evaluation of congenital malformation risks in newborn babies whose mothers has been exposed to thihalometanesEstanislao, Marcus Vinicius 24 April 2009 (has links)
Este estudo tratou de avaliar possíveis efeitos a saúde de recémnascidos cujas mães foram expostas ao trihalometanos (THM) contidos nas água de abastecimento público da cidade de São Paulo. O processo de tratamento da água de abastecimento utilizado no Brasil envolve uma etapa de desinfecção cujo objetivo é eliminar microorganismos patogênicos presentes na água. O cloro é um dos principais agentes desinfetantes. Apesar de pesquisas apontarem benefícios para a saúde humana no uso do cloro durante o processo de desinfecção, quando na água de abastecimento há a presença de matéria orgânica ocorrem reações entre essas substâncias que geram como subproduto, os THM. Estudos têm sido conduzidos para avaliar os efeitos da exposição ao THM e a ocorrência de eventos adversos na gravidez. Alguns destes trabalhos têm encontrado excesso de risco; outros não têm encontrado tal associação. Os artigos de revisão publicados sobre o assunto relatam que os resultados destas avaliações ainda são inconclusivos. O presente estudo objetivou avaliar se existe associação entre a exposição ao THM presente na água de abastecimento, utilizando para isso mensurações realizadas nas redes de distribuição da cidade de São Paulo, e a ocorrência de malformações congênitas. Foram considerados os seguintes desfechos: defeitos cardíacos, fenda labial e fenda palatina; anomalias cromossômicas, defeito no sistema nervoso central. Nesta classe, avaliou-se também o defeito do tubo neural. A população estudada foi composta de recém-nascidos de mães residentes na cidade de São Paulo cuja gestação foi única e a termo, no período de janeiro de 2002 a dezembro de 2006. As informações sobre os recém-nascidos foram obtidas do Sistema de Informação sobre Nascidos Vivos (SINASC). As concentrações de THM foram obtidas por meio de mensurações realizadas rotineiramente pela Companhia de Saneamento Básico de São Paulo (SABESP), nas redes de distribuição de água da cidade de São Paulo. A exposição ao THM atribuída a casos e controles foi determinada a partir da associação da medida realizada na rede de distribuição com o endereço residencial da gestante, no período da concepção. Os resultados encontrados apontaram que a exposição ao THM está inversamente associada às ocorrências de malformações avaliadas no estudo. A falta de informação quanto à mobilidade, origem e quantidade de água clorada à qual a gestante foi exposta, bem como a não avaliação de outras vias de exposição, além da ingestão, podem ter conduzido a vieses que subestimaram os riscos do efeito da exposição aos compostos. Este fato fortalece a necessidade de trabalhos mais aprofundados, avaliando mais criteriosamente a exposição materna ao THM e considerando também um melhor aprofundamento da investigação sobre a possibilidade de efeitos interativos de outros compostos clorados contidos na água de abastecimento. / This present application is going to deal about the potential effects related to the newborn babies health whose mothers had been exposed to the trihalomethanes (THM) that the water supply of the city of São Paulo contain. The water treatment process of supply used in Brazil has one stage of disinfection which purpose is eliminate the pathogenic microorganism presents in the water. Chlorine is one of the main disinfectant agents. Although researches indicates the chlorine benefits to human health when used in the disinfection process, when in the water supply has some organic material, some reactions can occur between these substances generating as a sub-product the trihalomethanes. Many studies is being conducted to consider the effects of the trihalomethanes (THM) exposition and the adverse events that can occur during pregnancy. Some of these studies have found excess of risks; others havent. The review articles published about this topic report that the results are still inconclusive. The present study wants to assess whether there is an association between exposures to THM in the water supply by means of measurements taken in the distribution networks of the city of São Paulo and the occurrence of congenital malformations, considering the following outcomes: cardiac defects, cleft lip and cleft palate, chromosomal abnormalities, defects in the central nervous system. It will also assess the neural tubes defect. The studied population was composed by mothers of newborn babies living in São Paulo, between January, 2002 and December, 2006, whose had a normal and single pregnancy. The information about the newborn was obtained from the SINASC (Information System about Live Births). The concentrations of trihalomethanes were obtained by measurements carried out routinely by SABESP (Basic Sanitation Company of the State of São Paulo) in water distribution networks of the city of São Paulo. The exposition to THM related to the cases and controls, was determined to the realized association in the distributed network with the pregnants address, in the period of conception. The results indicate that the exposition to THM is inversely associated with the malformations occurrence evaluated in the study. The lack of information about the mobility, origin and amount of chlorinated water to which the pregnant woman was exposed, as well as the non evaluation of others ways of exposure, instead of ingestion, may have led to bias which under-estimated the risks of the effect of exposure to the compounds. This fact shows that more specific researches must be done, evaluating more carefully the maternal exposure to the THM, and it also has to consider greater depth of research about the possibility of interactive effects of other chlorinated compounds in the water supply.
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Avaliação do risco de malformação congênita em recém-nascidos de mães expostas ao trihalometano / Evaluation of congenital malformation risks in newborn babies whose mothers has been exposed to thihalometanesMarcus Vinicius Estanislao 24 April 2009 (has links)
Este estudo tratou de avaliar possíveis efeitos a saúde de recémnascidos cujas mães foram expostas ao trihalometanos (THM) contidos nas água de abastecimento público da cidade de São Paulo. O processo de tratamento da água de abastecimento utilizado no Brasil envolve uma etapa de desinfecção cujo objetivo é eliminar microorganismos patogênicos presentes na água. O cloro é um dos principais agentes desinfetantes. Apesar de pesquisas apontarem benefícios para a saúde humana no uso do cloro durante o processo de desinfecção, quando na água de abastecimento há a presença de matéria orgânica ocorrem reações entre essas substâncias que geram como subproduto, os THM. Estudos têm sido conduzidos para avaliar os efeitos da exposição ao THM e a ocorrência de eventos adversos na gravidez. Alguns destes trabalhos têm encontrado excesso de risco; outros não têm encontrado tal associação. Os artigos de revisão publicados sobre o assunto relatam que os resultados destas avaliações ainda são inconclusivos. O presente estudo objetivou avaliar se existe associação entre a exposição ao THM presente na água de abastecimento, utilizando para isso mensurações realizadas nas redes de distribuição da cidade de São Paulo, e a ocorrência de malformações congênitas. Foram considerados os seguintes desfechos: defeitos cardíacos, fenda labial e fenda palatina; anomalias cromossômicas, defeito no sistema nervoso central. Nesta classe, avaliou-se também o defeito do tubo neural. A população estudada foi composta de recém-nascidos de mães residentes na cidade de São Paulo cuja gestação foi única e a termo, no período de janeiro de 2002 a dezembro de 2006. As informações sobre os recém-nascidos foram obtidas do Sistema de Informação sobre Nascidos Vivos (SINASC). As concentrações de THM foram obtidas por meio de mensurações realizadas rotineiramente pela Companhia de Saneamento Básico de São Paulo (SABESP), nas redes de distribuição de água da cidade de São Paulo. A exposição ao THM atribuída a casos e controles foi determinada a partir da associação da medida realizada na rede de distribuição com o endereço residencial da gestante, no período da concepção. Os resultados encontrados apontaram que a exposição ao THM está inversamente associada às ocorrências de malformações avaliadas no estudo. A falta de informação quanto à mobilidade, origem e quantidade de água clorada à qual a gestante foi exposta, bem como a não avaliação de outras vias de exposição, além da ingestão, podem ter conduzido a vieses que subestimaram os riscos do efeito da exposição aos compostos. Este fato fortalece a necessidade de trabalhos mais aprofundados, avaliando mais criteriosamente a exposição materna ao THM e considerando também um melhor aprofundamento da investigação sobre a possibilidade de efeitos interativos de outros compostos clorados contidos na água de abastecimento. / This present application is going to deal about the potential effects related to the newborn babies health whose mothers had been exposed to the trihalomethanes (THM) that the water supply of the city of São Paulo contain. The water treatment process of supply used in Brazil has one stage of disinfection which purpose is eliminate the pathogenic microorganism presents in the water. Chlorine is one of the main disinfectant agents. Although researches indicates the chlorine benefits to human health when used in the disinfection process, when in the water supply has some organic material, some reactions can occur between these substances generating as a sub-product the trihalomethanes. Many studies is being conducted to consider the effects of the trihalomethanes (THM) exposition and the adverse events that can occur during pregnancy. Some of these studies have found excess of risks; others havent. The review articles published about this topic report that the results are still inconclusive. The present study wants to assess whether there is an association between exposures to THM in the water supply by means of measurements taken in the distribution networks of the city of São Paulo and the occurrence of congenital malformations, considering the following outcomes: cardiac defects, cleft lip and cleft palate, chromosomal abnormalities, defects in the central nervous system. It will also assess the neural tubes defect. The studied population was composed by mothers of newborn babies living in São Paulo, between January, 2002 and December, 2006, whose had a normal and single pregnancy. The information about the newborn was obtained from the SINASC (Information System about Live Births). The concentrations of trihalomethanes were obtained by measurements carried out routinely by SABESP (Basic Sanitation Company of the State of São Paulo) in water distribution networks of the city of São Paulo. The exposition to THM related to the cases and controls, was determined to the realized association in the distributed network with the pregnants address, in the period of conception. The results indicate that the exposition to THM is inversely associated with the malformations occurrence evaluated in the study. The lack of information about the mobility, origin and amount of chlorinated water to which the pregnant woman was exposed, as well as the non evaluation of others ways of exposure, instead of ingestion, may have led to bias which under-estimated the risks of the effect of exposure to the compounds. This fact shows that more specific researches must be done, evaluating more carefully the maternal exposure to the THM, and it also has to consider greater depth of research about the possibility of interactive effects of other chlorinated compounds in the water supply.
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Cascades of genetic instability resulting from compromised break-induced replicationVasan, Soumini January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Break-induced replication (BIR) is a mechanism to repair double-strand breaks
(DSBs) that possess only a single end that can find homology in the genome. This situation can result from the collapse of replication forks or telomere erosion. BIR frequently produces various genetic instabilities including mutations, loss of heterozygosity, deletions, duplications, and template switching that can result in copy-number variations (CNVs). An important type of genomic rearrangement specifically linked to BIR is half crossovers (HCs), which result from fusions between parts of recombining chromosomes. Because HC formation produces a fused molecule as well as a broken chromosome fragment, these events could be highly destabilizing. Here I demonstrate that HC formation results from the interruption of BIR caused by a defective replisome or premature onset of mitosis. Additionally, I document the existence of half crossover instability cascades (HCC) that resemble cycles of non-reciprocal translocations (NRTs) previously described in human tumors. I postulate that HCs represent a potent source of genetic destabilization with significant consequences that mimic those observed in human diseases, including cancer.
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