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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.
41

Applications de l'hybridation in situ en fluorescence et stratégies moléculaires pour le diagnostic des infections bactériennes / Applications of fluorescence in situ hybridization and molecular strategies for the diagnosis of bacterial infections

Prudent, Elsa 05 July 2018 (has links)
Une partie de ce travail de thèse a consisté à appliquer les méthodes de FISH pour l’étude de trois bactéries pathogènes intracellulaires. La viabilité de Bartonella henselae a été évaluée à partir de ganglions de patients atteints de la maladie des griffes du chat (CSD). Le faible taux d’ARN détecté par biologie moléculaire, la stérilité des cultures, l'absence de détection par analyses histologiques et FISH confirment que B. henselae n'est pas ou rarement viable dans les ganglions de patients atteints de CSD. Tropheryma whipplei, l’agent de la maladie de Whipple, a été identifié et localisé par FISH, dans les macrophages d’un ganglion et d’une biopsie pulmonaire, confirmant le diagnostic infectieux. Deux méthodes de FISH ont été testées pour détecter Coxiella burnetii dans des cas d’endocardites et d’infections vasculaires en utilisant des sondes oligonucléotidiques et des sondes PNA. Les résultats ont confirmé une meilleure efficacité des sondes PNA et démontré que les techniques de FISH sont plus sensibles que l’immunohistochimie pour le diagnostic des endocardites et des infections vasculaires à C. burnetii. Nous avons également évalué les stratégies moléculaires mises en place pour le diagnostic syndromique. Bien que la PCR conventionnelle à large spectre permette l'identification de micro-organismes fastidieux et anaérobies, la PCR spécifique en temps réel révèle une supériorité significative dans le diagnostic syndromique. En conclusion, ce travail a permis de démontrer l’efficacité et l’applicabilité de la FISH pour la détection bactérienne. Cette méthode peut être utilisée comme un outil complémentaire afin d'améliorer le diagnostic de microbiologie clinique. / We applied FISH methods to the study of three intracellular pathogenic bacteria. The viability of Bartonella henselae was evaluated in a large series of lymph nodes from patients with cat scratch disease (CSD). The results obtained, associated with sterile cultures and negative histological analyzes and FISH, as well as the low level of RNA detected by molecular biology, provide evidence that B. henselae are not or are rarely viable in the lymph nodes of patients with CSD. Tropheryma whipplei has been identified by FISH in macrophages from one lymph node and for the first time in a pulmonary biopsy, confirming the diagnosis of infection. Two methods of FISH have been tested to detect Coxiella burnetii in cases of endocarditis and vascular infections using oligonucleotide and PNA probes. The results attested to the greater efficiency of PNA probes, and demonstrated that FISH were applicable for the diagnosis of C. burnetii endocarditis. We also evaluated the molecular strategies used for syndrome-driven diagnosis of infectious diseases. Although conventional broad-spectrum PCR allows for the identification of fastidious and anaerobic microorganisms, real-time specific PCR reveals a significant superiority in syndrome-driven diagnosis. The addition of specific PCRs in real time PCR would improve our molecular strategies, for example, in the case of the detection of Staphylococcus aureus for the diagnosis of lymphadenopathy. In conclusion, this work demonstrates the effectiveness and applicability of FISH for the identification of intracellular bacteria. This method can be used as an important complementary tool to the improvement of clinical microbiological diagnosis.
42

Roles of troponin I in heart development and cardiac function

Unknown Date (has links)
Two major troponin I (TnI) genes, fetal TnI (ssTnI) and adult TnI (cTnI), are expressed in the mammalian heart under the control of a developmentally regulated program. In this study, the up-stream domain (~1,800 bp) of mouse fetal TnI gene has been cloned and characterized. There is a high homology of this region among mouse, rat and human. Transfection assays indicated that conserved GA-rich sequences, CREB and a CCAAT box within the first 300 bp upstream of the transcription start site were critical for the gene expression. Electrophoretic mobility shift assays (EMSAs) and chromatin immunoprecipitation (ChIP) assays revealed binding proteins to CREB site in nuclear extracts from myocardial cells. Thyroid hormone (T3) caused a significant inhibitory effect on ssTnI expression in myocardial cells. Cardiac troponin I (cTnI) mutations have been linked to the development of restrictive cardiomyopathy (RCM) in human patients. We modeled one mutation in human cTnI Cv terminus, arginine1 92 histidine (R192H) by cardiac specific expression of the mutated protein (cTnI193His in mouse sequence) in transgenic mice. The main functional alteration detected in cTnI193His mice by ultrasound cardiac imaging examinations was impaired cardiac relaxation manifested by a decreased left ventricular end diastolic dimension (LVEDD) and an increased end diastolic dimension in both atria. Echocardiography revealed a series of changes on the transgenic mice including a reversed E-to-A ratio, increased deceleration time, and prolonged isovolumetric relaxation time. At the age of 12 months, cardiac output in cTnI193His mice was significantly declined, and some transgenic mice showed congestive heart failure. The negative impact of cTnI193His on ventricular contraction and relaxation was further demonstrated in isolated mouse working heart preparations. / Dobutamine stimulation increased heart rate in cTnI193His mice but did not improve CO.The cTnI193His mice had a phenotype similar to that in human RCM patients carrying the cTnI mutation. The results demonstrate a critical role of the COOH-terminal domain of cTnI in the diastolic function of cardiac muscle. This mouse model provides us with a tool to further investigate the pathophysiology and the development of RCM. / by Jianfeng Du. / Thesis (Ph.D.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2008. Mode of access: World Wide Web.
43

Estudo do Papel do Gene SLC26A4 na Surdez Neurossensorial Não-Sindrômica Pré-Lingual em uma Série de Casos no Sudeste Brasileiro / Study of the Role of SLC26A4 Gene in Non-Syndromic Sensorineural Prelingual Deafness in a Series of Cases in Southeastern Brazil

Carvalho, Simone da Costa e Silva 06 May 2015 (has links)
A audição representa a principal fonte para o aprendizado da fala e linguagem durante a infância e a surdez e a privação de estímulos auditivos pode implicar em dificuldades emocionais e sociais àqueles indivíduos afetados. Aproximadamente 360 milhões de pessoas sofrem de perda auditiva no mundo, o que corresponde a 5,3% da população mundial. A surdez pode se desenvolver em decorrência de causas genéticas (hereditárias), não-genéticas e ambientais. As infecções pré-natais e a exposição a ruídos constituem as causas ambientais mais comuns. Já a surdez hereditária, constitui o transtorno neurossensorial mais comum em humanos, com uma prevalência de 1:1000 nascidos vivos. Mais de 70% dos casos de surdez hereditária constituem casos não-sindrômicos, destes cerca de 70% cursam com surdez congênita ou pré-lingual. Na maioria dos casos, a perda auditiva hereditária é neurossensorial, heterogênea, com diferentes padrões de herança e com uma grande quantidade de genes envolvidos. Estudos têm demonstrado o importante papel dos genes GJB2, GJB6 e SLC26A4 na fisiologia do ouvido interno e alterações nestes genes têm sido relatadas como causa da surdez hereditária. Desta forma, o objetivo deste estudo foi investigar a base genética e o papel do gene SLC26A4 na perda auditiva neurossensorial (PANS) nãosindrômica pré-lingual em pacientes atendidos pelo serviço de Genética Médica do Hospital das Clínicas de Ribeirão Preto. Para isso, uma série de 88 casos foi investigada quanto a características clínicas e moleculares. A amostra abrangeu indivíduos de ambos os sexos, com idade de 2 a 63 anos, provenientes de 88 famílias diferentes, assistidos durante o período de 2003 a 2013. As amostras foram triadas pela técnica de High Resolution Melting (HRM) e em seguida levadas para o seqüenciamento para caracterização das alterações. Na série de casos estudada, 23,9% (21/88) dos pacientes portadores de surdez neurossensorial não-sindrômica pré-lingual evidenciaram alterações nos genes GJB2, GJB6 e SLC26A4 sugeridas como patogênicas. A prevalência de alterações no gene SLC26A4 foi de 28,4% (25/88), não relacionada à Síndrome do Aqueduto Vestibular Alargado (SAVA). Dentre as 11 alterações encontradas neste gene, três constituem mutações não descritas: p.Gly139Arg, p.Ile254Val, p.Asn382Lys. Os genótipos mais freqüentes neste estudo foram a c.35delG/c.35delG no gene GJB2 (5/88), a dupla heterozigose com o gene GJB6 c.35delG/del(GJB6-D13S1854) (3,4%) e chr7:g.107301238C>G/wt no gene SLC26A4 (10,2%). Entretanto, apenas 19,3% dos indivíduos apresentaram genótipos sugeridos como responsáveis pelo fenótipo estudado. Alterações particulares no gene SLC26A4 podem sugerir a explicação para a surdez genética para aproximadamente 9,1% destes casos. Destes, cinco casos de heterozigose preditas como patogênicas (p.Ile300Leu; p.Asn324Tyr e p.Asn382Lys), dois casos de heterozigose composta (chr7:g.107301201T>C/chr7:g.107301238C>G e chr7:g.107301238C>G/p.Gly139Arg) e um caso de dupla heterozigose com GJB2 (chr7:g.107301238C>G/c.35delG). Isto ressalta a importância do gene SLC26A4 para o diagnóstico molecular de surdez hereditária e reforça a sua potencial contribuição para o processo de aconselhamento genético. Entretanto, nossos dados sugerem a necessidade de testes funcionais a fim de elucidar o papel destas alterações para o estabelecimento do fenótipo, como também, a presença de outros genes ou regiões envolvidas naqueles casos em que mutações monoalélicas não foram suficientes para justificar o fenótipo. / The hearing is the main source for learning speech and language during childhood and deafness and deprivation of auditory stimuli can result in emotional and social difficulties to those affected individuals. Approximately 360 million people suffer from hearing loss worldwide which corresponds to 5.3% of the world population. Deafness may develop due to genetic (hereditary), non-genetic and environmental causes. Prenatal infections and exposure to noise are the most common environmental causes. Hereditary deafness is the most common sensorineural disorder in humans, with a prevalence of 1:1000 live births. More than 70% of hereditary deafness cases are nonsyndromic, about 70% of these occur with congenital or prelingual deafness. In most cases, inherited sensorineural hearing loss is heterogeneous, with different patterns of inheritance and with a large number of genes involved. Studies have shown the important role of genes GJB2, GJB6 and SLC26A4 in the physiology of the inner ear and changes in these genes have been reported as cause of hereditary hearing loss. Thus, the aim of this study was to investigate the genetic basis and the role of SLC26A4 gene in non-syndromic prelingual sensorineural hearing loss (SNHL) in patients enrolled in the Medical Genetics Service of Hospital das Clínicas de Ribeirão Preto. For this, a series of 88 cases were submitted to a clinical and molecular investigation. The sample consisted of individuals of both sexes, aged 2-63 years from 88 different families, assisted during the period 2003-2013. The samples were screened by the technique of High Resolution Melting (HRM) and then taken for sequencing to characterize the mutations. In the series of cases studied, 23.9% (21/88) of patients with non-syndromic prelingual sensorineural deafness showed variants in genes GJB2, GJB6 and SLC26A4 suggested as pathogenic. The prevalence of mutations in the SLC26A4 gene was 28.4% (25/88), not related to non-syndromic EVA. Among the 11 mutations found in this gene, three are reported as novel mutations: p.Gly139Arg, p.Ile254Val, p.Asn382Lys. The most frequent genotypes found in this study were the c.35delG/c.35delG in GJB2 gene (5/88), the double heterozygosity with GJB6 gene c.35delG/del(GJB6-D13S1854) (3,4%) and chr7:g.107301238C>G/wt in the SLC26A4 gene (10,2%). However, only 19.3% of subjects presented genotypes suggested as responsible for the studied phenotype. Particular mutations in the SLC26A4 gene may suggest the explanation for the genetic deafness to approximately 9.1% of these cases. Of these, five cases of heterozygosity predicted as pathogenic (p.Ile300Leu; p.Asn324Tyr and p.Asn382Lys), two cases of compound heterozygosity (chr7:g.107301201T>C/chr7:g.107301238C>G and chr7:g.107301238C>G/p.Gly139Arg) and one case of double heterozygosity with GJB2 gene (chr7:g.107301238C>G/c.35delG). Those data highlights the importance of the SLC26A4 gene for molecular diagnosis of hereditary hearing loss and give strength to its potential contribution to the genetic counseling process. However, our data suggest the need for functional tests in order to elucidate the role of these changes to the phenotype, as well as the presence of other genes or regions involved in those cases that monoallelic mutations were not sufficient to justify the phenotype.
44

Detecção e quantificação do vírus da hepatite E (HEV) por RT-PCR em tempo real e estudo experimental em primatas neotropicais (Aotus azarai infulatus) infectados pelo genótipo 3 do HEV / Detection and quantification of hepatitis E virus (HEV) by real time RT-PCR and experimental study in neotropical monkeys (Aotus azarai infulatus) infected by HEV genotype 3

Souza, Alex Junior Souza de 15 March 2017 (has links)
O vírus da hepatite E (HEV) é um patógeno emergente de distribuição global, causador de hepatite aguda e crônica em humanos e infecções assintomáticas em animais. No Brasil a prevalência de infecção por HEV em humanos e animais ainda é pouco compreendida, assim como as características de virulência, patogenicidade e de infecção inter-espécies de isolados do genótipo 3, zoonótico, circulantes no país também são desconhecidas. O estudo foi dividido em duas etapas, com os objetivos de 1) contribuir no diagnóstico laboratorial molecular do HEV a partir do desenvolvimento de um protocolo de RT-PCR em tempo real (RT-qPCR) para pesquisa do HEV em amostras biológicas, e 2) contribuir com a compreensão das características moleculares, sorológicas, clínico-laboratoriais, ultrassonográficas e histopatológicas associadas à infecção experimental em macacos-da-noite (Aotus azarai infulatus) por um isolado do genótipo 3 suíno do HEV previamente detectado na Amazônia oriental brasileira. O protocolo de RT-qPCR foi desenvolvido com a caracterização da curva de detecção e aplicado em concomitância com testes sorológicos para avaliação diagnóstica restrospectiva de 318 (n = 318) amostras de soros humanos suspeitos de hepatite E. O HEV-RNA não foi detectado em nenhuma das amostras humanas testadas, mas foi determinada soroprevalência de 3,4% e 5,9% de anti-HEV IgM e IgG, respectivamente, o que indicou baixa prevalência de infecção por HEV, mesmo entre pacientes com suspeita clínica e/ou laboratorial de hepatite E na Amazônia brasileira. O estudo experimental em macacos-da-noite foi desenvolvido durante 12 semanas e os animais infectados, por via intravenosa (n=3) e oral (n=3) (e dois controles), foram avaliados semanalmente para determinação dos parâmetros clínicos, bioquímicos, hematológicos, sorológicos (pesquisa de anti-HEV IgM e IgG por enzimaimunoensaio) e moleculares (HEV-RNA soro e fezes por RT-qPCR). Adicionalmente, os animais também foram submetidos a avaliação hepática mensal por ultrassonografia, histopatologia e pesquisa hepática de antígenos do HEV por imunohistoquímica. Os seis macacos-da-noite infectados apresentaram o HEV-RNA em amostras de soro e/ou fezes, e alguns apresentaram evidências de soroconversão, detecção hepática do antígeno viral por imunohistoquímica associada a alterações clínicas e laboratoriais de hepatite aguda oligossintomática. Assim, o protocolo RT-qPCR demonstrou ser aplicável na pesquisa molecular do HEV em amostras de humanos e animais, representando uma importante ferramenta de diagnóstico laboratorial. O estudo experimental permitiu a primeira validação de um primata neotropical como modelo experimental para estudos de infecção com o genótipo 3 do HEV. / Hepatitis E virus (HEV) is an emerging pathogen with global distribution that causes acute and chronic hepatitis in humans and asymptomatic infections in animals. In Brazil, the prevalence of HEV infection in humans and animals is still poorly understood, and the characteristics of virulence, pathogenicity and inter-species infection of the genotype 3 isolates circulating in the country are unknown. The study was divided in two stages that aimed to 1) contribute to the molecular diagnosis of HEV infection by the development of a real-time RT-PCR protocol (RT-qPCR) for HEV-RNA research in biological samples, and 2) to contribute to understanding of molecular, serological, clinical-laboratory, ultrasonographic and histopathological features of HEV genotype 3 in owl monkeys (Aotus azari infulatus) experimental infected with isolate of swine HEV genotype 3 previously detected in the Eastern Brazilian Amazon. The RT-qPCR protocol was developed with characterization of a quantification standard curve and later applied concurrently with serological tests in the retrospective evaluation of 318 (n = 318) human serum samples of hepatitis E suspected cases. HEV-RNA was not detected in any of human tested samples, but seroprevalence of 3.4% and 5.9% was determined for anti-HEV IgM and IgG, respectively, that indicated a low prevalence of HEV infection, even among patients with clinical and/or laboratory suspicion of hepatitis E in the Brazilian Amazon. The experimental study in owl monkeys was developed during12 weeks and the animals were infected by intravenous (n = 3) and oral (n = 3) routes (and two negative controls) were evaluated for determination of clinical, biochemical, hematological, serological (anti-HEV IgM and IgG by enzyme immunoassay) and molecular (HEV-RNA serum and stool by RT-qPCR) parameters weekly. Additionally, the animals were also evaluated by hepatic ultrasonography, histopathology and immunohistochemistry research of HEV antigens in liver monthly. The six infected owl monkeys presentend HEV-RNA in serum and/or stool, and some monkeys presented with evidence of seroconversion, liver detection of HEV antigens by immunohistochemistry associated with clinical and/or laboratory findings of oligosymptomatic acute hepatitis. Thus, the RT-qPCR protocol demonstrated to be applicable in the molecular investigation of HEV infection in human and animal samples, and it also represented an important laboratory diagnostic tool. The experimental study allowed the validation of the first neotropical primate model for HEV genotype 3 infection studies.
45

"Análise molecular das doenças de Gaucher e Tay-Sachs no Brasil" / Molecular analysis of Gaucher and Tay-Sachs disease in Brazil

Rozenberg, Roberto 17 August 2006 (has links)
Este estudo descreve a análise molecular de pacientes da doença de Gaucher (DG) e Tay-Sachs (DTS) no Brasil. Foram estudados nove casos de formas clássicas da DTS que mostraram uma prevalência da mutação IVS7+1g>c, já descrita em pacientes Portugueses e dez casos das variantes de início juvenil e tardio da DTS, mostrando heterogeneidade genética. Nos casos da variante B1, percebeu-se uma maior incidência da mutação R178H, também descrita previamente em pacientes Portugueses. A presença das mesmas mutações nos casos Brasileiros e Portugueses se deve provavelmente à ancestralidade comum. Uma família com quatro pacientes da variante de início tardio da DTS mostrou uma extensa variabilidade clínica intrafamilial e identificou relevantes aspectos do diagnóstico e das implicações dos programas de triagem populacional. A análise por RFLP de nove mutações causadoras da DG, em 262 pacientes permitiu detectar 76% das alterações e mostrou uma prevalência das mutações N370S e L444P, similar à descrita em diversas outras populações. Os pacientes com variantes neuronopáticas da doença apresentaram uma alta freqüência da mutação G377S, que também é encontrada em pacientes Portugueses. Os pacientes apresentando a G377S indicaram a existência de um provável mecanismo de efeito de dose alélica para essa mutação. Foi observada uma alta freqüência de alelos resultantes da recombinação do gene GBA com seu pseudogene. Diversas outras relações genótipo-fenótipo puderam ser verificadas, mostrando uma baixa penetrância do genótipo N370S/N370S e corroborando a importância do diagnóstico molecular da DG, devido a seu valor preditivo. A análise de mutações raras no gene GBA usando as técnicas de RFLP, dHPLC e seqüenciamento de DNA possibilitou detectar mutações em 84% dos alelos de 54 pacientes. Foram identificadas 14 novas mutações causadoras da DG. Diversas relações genótipo-fenótipo puderam ser verificadas, conferindo valor preditivo para a detecção dessas mutações. Por fim, a análise da associação da DG e da DP permitiu encontrar uma freqüência significativamente maior de portadores das principais mutações no gene GBA em pacientes parkinsonianos (2/65=3%), com aparecimento precoce da doença, comparados a um grupo controle de 267 indivíduos. Esse trabalho fornece nova evidência de que mutações no gene GBA são um raro, mas consistente fator de risco para a DP. / This study describes the molecular diagnosis of Gaucher (GD) and Tay-Sachs disease (TSD) patients in Brazil. Nine cases of the classic infantile form of TSD were analyzed disclosing a prevalence of the IVS7+1g>c mutation, described previously in Portuguese patients. Ten cases of juvenile and late-onset TSD forms were diagnosed showing genetic heterogeneity. Among the B1 variant cases, there was a predomenance of mutation R178H that was also associated to Portuguese ancestry. The presence of the same mutations in Brazilian and Portuguese cases are probably due to common ancestry. A family with 4 affected patients of late onset TSD showed and extensive intrafamilial clinical variability, highlighting relevant characteristics of diagnosis and implications of heterozygote screening programs. Among 263 GD patients, the detection of nine mutations by RFLP revealed 76% of the mutant alleles and a preponderance of N370S and L444P, similar to other populations. The type 3 neuronopathic patients presented a high frequency of mutation G377S, that is also described among Portuguese cases. The patients with G377S indicated the possibility of an allele dose effect for this mutation. Recombinant alleles, presenting pseudogene mutations were detected at a high frequency. Several genotype-phenotype correlations could be verified, highlighting a low penetrance of genotype N370S/N370S and corroborating the importance of molecular diagnosis in GD cases, due to its predictive value. The search for rare mutations at the GBA gene, using dHPLC and DNA sequencing after RFLP analysis, allowed the detection of 84% of the alleles among 54 patients. Fourteen new GD causing mutations were described. Several genotype-phenotype correlations could be established, confering prective value to the identification of these mutations. Finally, the study of the association of GD and Parkinson disease (PD) lead to the detection of a significant increase in the frequency of GBA mutations carriers, among 65 PD patients (2/65=3%) with earlier disease onset compared to a control group (n=267 individuals). This work confers further evidence for the fact that GBA mutations are a rare but consistent risk factor for PD.
46

Genes de cisteíno proteases (catepsina L-like) de Leishmania infantum chagasi: caracterização, relações filogenéticas e diagnóstico molecular / Genes of Cysteine proteases (Cathepsin L-like) from Leishmania infantum chagasi: characterization, phylogenetic relations and molecular diagnosis

Silva, Ryan Emiliano da 21 February 2018 (has links)
Os parasitas pertencentes ao gênero Leishmania têm distribuição ubíqua. Este táxon inclui Leishmania infantum chagasi, agente etiológico da leishmaniose visceral nas Américas, uma zoonose negligenciada cujas metodologias diagnósticas acumulam uma série de limitações, requerendo a validação e padronização de metodologias diagnósticas satisfatórias. Vários fatores estão relacionados à patogênese causada por este protozoário, entre eles a catepsina L-like, uma cisteíno protease envolvida em processos regulatórios metabólicos e infecciosos. Portanto, este trabalho teve como objetivo avaliar a eficácia do gene de catepsina L-like isoforma CPA como alvo de diagnóstico molecular e como marcador filogenético que permita a compreensão das variações intraespecíficas e elucidem a história evolutiva de L. infantum chagasi no Brasil. Foram utilizados 44 isolados de L. infantum chagasi de diferentes estados brasileiros. Os fragmentos do gene de catepsina L-like foram amplificados, purificados, sequenciados, alinhados manualmente e analisados por métodos filogenéticos de máxima parcimônia e inferência bayesiana. As sequências geradas foram usadas para pesquisar e sintetizar iniciadores a serem usados em reações específicas para o parasita alvo. O gene de catepsina L-like não mostrou variabilidade intraespecífica entre os isolados analisados, sugerindo um evento recente de introdução do mesmo nas Américas. O par de iniciadores propostos amplificou o DNA alvo de isolados de L. infantum chagasi, sendo efetivo na amplificação de DNA em concentrações de até 10-11g / µl. O marcador proposto não apresentou reações cruzadas com outros hemoparasitas de importância clínica. Quando utilizado para o diagnóstico em um painel de amostras clínicas de cães, obteve-se uma frequência de positividade de 49,03% (102/208), contrastando com o valor de 14,42% (30/208) obtido com o marcador para o gene do espaçador ribossomal interno ITS. Quando testado em amostras de flebotomíneos se obteve um valor de 6,25% e em amostras de pacientes humanos o valor foi de 14,28%. Os marcadores também foram eficazes em amplificar DNA extraído de amostras de urina, de sangue fixado em papel filtro e mesmo em amostras de swab de lesões conjuntivas. Este conjunto de parâmetros permite inferir que o CatLeish- PCR é sensível e específico para o diagnóstico de L. infantum chagasi podendo ser aplicado tanto em pesquisas clínicas quanto em inquéritos epidemiológicos de vigilância. / The parasites belonging to the Leishmania genus have a wide distribution. This taxon includes Leishmania infantum chagasi, the etiologic agent of Visceral Leishmaniasis in the Americas, a neglected zoonosis that requires the validation and standardization of satisfactory diagnostic methodologies. Several factors are related to the pathogenesis caused by this protozoan, as Catepsin L-like, a cysteine protease involved in regulatory and infectious processes. Given this information this work aimed to evaluate the effectiveness of Cathepsin L-like isoform CPA as a target for molecular diagnosis and as a phylogenetic marker that allows understanding the intraspecific variations and the evolutionary history of L. infantum chagasi in Brazil. We used 44 isolates of L. infantum chagasi from different Brazilian states. The cathepsin L-like gene fragments were amplified, purified, sequenced, manually aligned and analyzed by maximum parsimony and Bayesian inference methods. The sequences generated were researched to construction of oligonucleotide primers to be used in reactions specific to the target parasite. The Cathepsin L-like gene did not show intraspecific variability among the isolates analyzed, suggesting a recent event of introduction of the same in the Americas. The pair of proposed primers amplified the target DNA of L. infantum chagasi isolates, being effective in DNA amplification at concentrations of up to 10-11g/µl. The proposed marker did not present cross-reactions with other hemoparasites of clinical importance. When used for the diagnosis in a panel of clinical samples of dogs obtained a positive frequency of 49.03% (102/208), against the 14.42% (30/208) to ribosomal ITS marker. Samples of sandflies obtained a value of 6.25% and in humans the value was 14.28%. The markers were also effective in blood samples fixed on filter paper and even in samples from conjunctival lesion swabs. This set of parameters allows to infer that CatLeish-PCR is a sensitive and specific marker for the diagnosis of L. infantum chagasi in clinical and epidemiological surveys.
47

Assessment of anatomical structures and hemodynamic function of cTnI[193His] transgenic mice with micro-echocardiography

Unknown Date (has links)
Transgenic mice were generated to express a restrictive cardiomyopathy (RCM) human cardiac troponin I (cTnI) R192H mutation in the heart. My study's objective was to assess cardiac function during the development of diastolic dysfunction and to gain insight into the pathophysiological impact of the RCM cTnI mutation. Cardiac function was monitored in cTnI193His mice and wild-type littermates for a period of 12 months. It progressed gradually from abnormal relaxation to diastolic dysfunction characterized with micro- echocardiography by a reversed E/A ratio, increased deceleration time, and prolonged isovolumetric relaxation time. The negative impact of cTnI193His on cardiac function was further demonstrated in isolated mouse working heart preparations. Dobutamine stimulation increased heart rate in cTnI193His mice but did not improve CO. The cTnI193His mice had a phenotype similar to that in human RCM patients carrying the cTnI mutation characterized morphologically by enlarged atria and restricted ventricle and functionally by diastolic dysfunction. / by Nariman Gobara. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
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Cytogenetic of chromosomal synteny evaluation: bioinformatic applications towards screening of chromosomal aberrations/ genetic disorder

Unknown Date (has links)
The research efforts refer to tracking homologus loci in the chromosomes of a pair of a species. The purpose is to infer the extent of maximum syntenic correlation when an exhaustive set of orthologs of the species are searched. Relevant bioinformatic analyses use comparative mapping of conserved synteny via Oxford grid. In medical diagnostic efforts, deducing such synteny correlation can help screening chromosomal aberration in genetic disorder pathology. Objectively, the present study addresses: (i) Cytogenetic framework of syntenic correlation and, (ii) applying information-theoretics to determine entropy-dictated synteny across an exhaustive set of orthologs of the test pairs of species. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
49

Mechanisms of Placental Dysfunction in Pregnancy Malaria

Unknown Date (has links)
The molecular mechanisms by which pregnancy malaria affects the outcome of fetal development are unknown. Megalin, which has been well studied in kidney, has high expression in the placenta from early stages to term, and is proposed to be an important factor in extensive maternofetal exchange during development of the fetus. Pregnancy malaria (PM) is characterized by inflammation in placenta and is associated with low birthweight (LBW), stillborn birth, and other pathologies. It is hypothesized that PM disturbs megalin function/expression/distribution in the brush boarder of syncytiotrophoblast which, in turn, may contribute significantly to pathology of LBW. Our studies show that the presence of infected erythrocytes in placenta at the time of delivery negatively affects protein abundance for megalin and Dab2. This is the first report associating the abundance of placental megalin system proteins with the birth weight of newborn babies, and associating PM with changes in megalin system protein abundance. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
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Amplificação de DNA de Neisseria meningitidis em amostras de líquido cefalorraquidiano pela reação em cadeia da polimerase-multiplex / Multiplex-PCR for the diagnosis of meningococcal meningitis in cerebral spinal fluid

Atobe, Jane Harumi 30 September 1998 (has links)
Padronizou-se a PCR-Multiplex para a detecção do DNA de Neisseria meningitidis. Para tanto os primers escolhidos foram: RW01, DG74 e COR28 baseados na subunidade menor do ribossomo (16S rRNA) que apresenta regiões de seqüências conservadas encontradas em todas as bactérias conhecidas. Os primers RW01 e DG74 amplificaram o fragmento universal bacteriano de 370 bp e, os primers RW01 e COR28, o fragmento específico de N. meningitidis de 279 bp em uma única etapa. Os resultados obtidos nas amostras de LCR de 168 pacientes pelos métodos de cultura e PCR-Multiplex quando comparados à bacterioscopia mostraram que tal técnica apresentou alta sensibilidade (91,3%) no estudo de amostras de LCR de bacterioscopia positiva, enquanto que a cultura apresentou resultados menores (19,7%). Nas amostras de LCR com bacterioscopia negativa a sensibilidade da PCR-Multiplex (57,8%) também foi mais elevada do que da cultura (10%). Estes dados sugerem que a técnica aqui padronizada é altamente promissora para ser utilizada como método diagnóstico da meningite meningocócica, especialmente nos casos de pacientes submetidos à terapia antibiótica prévia. / The PCR-multiplex technique was standardized to detect N.meningitidis DNA. It was used universal primer for all bacteria showing sequence of minor subunit of 16S ribossome regions (RW01, DG74) by amplification of 370bp fragment and another (COR28) for specific sequence of N. meningitidis, amplifying 279bp fragment in one step. The results obtained in CSF samples of 168 patients by culture and PCR-Multiplex technique when compared with microscopy showed high sensitivity (91,3%) in samples with positive microscopy (81) to Gram negative diplococcus, however the culture presented only 19, 7% of positivity in the same samples. In other hand the CSF samples with negative bacterioscopy (67) the PCR-Multiplex sensitivity (57,8%) was higher to culture (10,0%) too. These data indicate a high sensitivity and specificity of PCR as a tool for a rapid diagnosis of meningococcal meningitis, mainly in that patient submitted to previous antibiotic therapy as in case of this work (90% of patients) besides the possibility of a rational practice of specific treatment.

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