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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.
131

Hledání genetických a molekulárních příčin familiární formy SAA amyloidózy / Identification of genetic and molecular underpinnings of familiar form of SAA amyloidosis

Kmochová, Tereza January 2020 (has links)
This work documents the first case of idiopathic AA amyloidosis in humans caused by mutation in the promoter region of SAA1 gene. Knowledge of the mechanism of the disease may be an indication for targeted treatment in the future. Mutations in the SAA1 promoter should be considered in all cases of idiopathic forms of AA amyloidosis in which neither the immune nor the inflammatory component of the disease are clearly present.
132

Värdet av diagnostik vid sällsynta sjukdomar : En hälsoekonomisk undersökning med två fall / The value of diagnostics in rare diseases : A health economic evaluation with two cases

Runheim, Hannes, Appelberg, Kajsa January 2021 (has links)
I denna studie undersöks värdet av diagnostik vid sällsynta sjukdomar hos unga individer. Då området är mångfacetterat studeras två fall med olika karaktär. Det första fallet undersöker värdet av screening för den sällsynta sjukdomen fenylketonuri (PKU) bland nyfödda, denna screening har utförts sedan 1960-talet. Det andra fallet fokuserar på en mer modern teknologisk utveckling och utvärderar värdet av införandet av helgenomsekvensering (WGS) som genetiskt test vid sökandet efter sällsynta sjukdomar.  Båda fallen använder sig av kostnadseffektivitetsanalys som metod där kostnader respektive hälsoeffekter estimeras för de utvärderade insatserna. Fallen skiljer sig åt med avseende på tillgängliga dataunderlag vilket innebär att tillvägagångssättet för att skatta kostnaderna och hälsoeffekterna är olika i de båda fallen. I fallet med PKU-screening används Markovmodellering där data från olika källor syntetiseras i en simuleringsmodell. I fallet med WGS-testning används i större utsträckning ett insamlat empiriskt datamaterial som utgörs av faktiskt uppmätta sjukvårdskostnader.  Resultaten i båda fallen indikerar att de diagnostiska metoderna har en rimlig kostnad i förhållande till hälsoeffekterna. Fall ett åskådliggör att dagens screening för PKU genererar ökade hälsoeffekter till lägre kostnader i jämförelse med att inte screena för PKU. För en kohort på 100 000 nyfödda barn blir den sammanlagda hälsoeffekten en ökning med 73 QALYs och screeningen medför samtidigt en besparing på 53 376 602 kr, sett över ett livstidsperspektiv. Fall två visar att WGS som första genetiskt test i genomsnitt minskar sjukvårdskostnaderna med 15 903 kr per individ jämfört med nuvarande vård och ökar samtidigt chansen till diagnos med 9,5 procentenheter (45,7%). Resultaten bör tolkas med viss försiktighet då de är förknippade med osäkerheter, men kan samtidigt användas som en del av det underlag beslutsfattare behöver för att fatta beslut om hur hälso- och sjukvårdens resurser ska prioriteras. / This study examines the value of diagnostics in rare diseases in young individuals. As the field is varied, two cases with different character are studied. The first case examines the value of screening for the rare disease phenylketonuria (PKU) among newborns, this screening has been performed since the 1960s. The second case focuses on a more modern technological development and evaluates the value of the introduction of whole genome sequencing (WGS) as a genetic test in the search for rare diseases.  Both cases utilize the method of cost-effectiveness analysis where costs and health effects are estimated for the evaluated measures. The cases differ regarding available data, which means that the approach to estimating costs and health effects is different in the two cases. In the case of PKU- screening, Markov modeling is used where data from different sources are synthesized in a simulation model. In the case of WGS-testing, an empirical data material is used to a greater extent, which is based on actually measured healthcare costs.  The results in both cases indicate that the diagnostic methods have a reasonable cost in relation to the health effects. Case one illustrates that today's screening for PKU generates increased health effects at lower costs compared to not screening for PKU. For a cohort of 100 000 newborns, the total health effect will be an increase of 73 QALYs and the screening will also result in cost- savings of SEK 53 376 602, seen from a lifetime perspective. Case two shows that WGS used as an initial genetic test on average reduces healthcare costs by SEK 15 903 per individual compared with current care and at the same time increases the chance of diagnosis by 9.5 percentage points (45.7%). The results should be interpreted with some caution as they are associated with some uncertainties, but can still be used as part of the basis on which decision-makers need to make decisions on how health care resources should be prioritized.
133

Neanderthal genome sequencing : A genetic research study / Neandertal genom sekvensering : En genetisk forskningsstudie

Uhr, Susanna January 2023 (has links)
The aim of this study is to provide information regarding the development of aDNA research. The essay also strives to distinguish eventual impact on previous and contemporary conceptions concerning Neanderthal and modern human genetic divergence and possible interbreeding between the two species. Relatively recent Neanderthal genetic research will provide a glimpse into future explorations. Hominin species, other than Neanderthals, will be excluded from this paper as well as morphological studies and modern human evolution theories. Nature, Cell, Science, American anthropologist are examples of important publications constituting the study’s source material generated through the mandatory literature search. Genetic data results reveal genetic divergence between Neanderthals and modern humans approximately around 270 000 to 440 000 years ago or 550 000 to 765 000 years ago. The estimations for genetic divergence continue to alter with the advent of additional data. Contemporaneous genomic data results show interbreeding between Neanderthals and modern humans which contradict some prior perceptions surrounding the subject. New engendered Neanderthal genomic data indicate further exploration concerning the Neanderthal inherited genes effect on modern day human biology and physiology. / Syftet med denna studie är att delge informativ upplysning kring utvecklingen av aDNA forskning. Uppsatsen strävar även efter att urskilja eventuell påverkan på föregående och nuvarande uppfattningar angående genetisk splittring mellan Neandertalare och moderna människor och möjlig korsning mellan de två arterna. Relativt ny genetisk Neandertal forskning kommer att ge en inblick i framtida utforskningar. Andra homininer, undantagsvis för Neandertalarna, kommer att exkluderad från denna uppsats liksom morfologiska studier och teorier kring den moderna människans evolution. Nature, Cell, Science, American anthropologist är exempel på viktiga publiceringar som utgör studiens källmaterial vilket genererats genom den obligatoriska litteratursökningen. Genetiska data resultat visar genetisk splittring mellan Neandertalare och moderna människor proximalt kring 270 000 till 440 000 år sedan eller 550 000 till 765 000 år sedan. Beräkningarna för genetisk splittring ändras kontinuerligt på grund av ankomsten av nytillkommande data. Nya genomiska data resultat visar korsning mellan Neandertalare och moderna människor vilket motsäger en del föregående föreställningar kring ämnet. Ny framställd Neandertal genomiska data indikerar vidare utforskning av de ärvda Neandertal genernas möjliga påverkan på den moderna människans biologi och fysiologi.
134

A Novel Mutational Approach to Uncover Genetic Determinants of Hybrid Vigor in Maize

Emily A Kuhn (16642218) 07 August 2023 (has links)
<p>Heterosis, or hybrid vigor, is a phenomenon observed in both plant and animal systems where hybrid offspring perform better when compared to their parents. For hybrid plants, this can result in increased biomass, crop yields, and vigor when compared to the inbred parents. Even though heterosis has been used in agriculture for over a century, the molecular mechanisms that result in hybrid vigor remain elusive even after years of investigation. A molecular understanding of heterosis is desirable because it will speed up the process of breeding compatible inbred lines for developing hybrid seeds, and it will provide us with the knowledge to potentially engineer inbred lines that can mimic the beneficial phenotypic effects of heterosis, eliminating the need for farmers to buy new hybrid seeds every year. The goal of this research project is to identify genes that are required for heterotic phenotypes in maize. Our working hypothesis is that a mutation in genes that are essential for heterosis will cause an altered heterotic phenotype in hybrid maize plants. To test this hypothesis, we applied combined approaches of EMS mutagenesis, trait phenotyping in field and controlled conditions, bulk segregant analysis, whole genome sequencing, and bioinformatics analysis. First, we applied a forward genetics approach to identify mutant hybrids with altered heterosis and detected potential causal genes <em>via</em> whole genome sequencing. We identified one mutation occurring in a protein coding gene (gene ID <em>Zm00001eb305590</em>) located in a region of interest on chromosome 7, whose genotypes across various samples assayed fit the observed segregation pattern of hybrid traits. This mutation leads to a moderate or high-level codon change, indicating that this gene may play a role in mediating heterosis in maize. By investigating this gene with further studies, the learned knowledge could speed up the process of hybrid maize breeding by selecting compatible inbred lines through sequencing or by engineering hybrids that have favorable alleles for this gene.</p>
135

Detection of Species-Specific <i>Plasmodium</i> Infection Using Unmapped Reads From Human Whole Genome Sequences

Olvany, Jasmine Marie 26 May 2023 (has links)
No description available.
136

Synergizing Microbial Culturing, Whole Genome Sequencing, Asymmetric Synthesis and Tandem MS for Reconstruction of Polyketide and Alkaloid Natural Product Biosynthesis in Marine Actinomycete Nocardiopsis sp CMB- M0232

Alqahtani, Norah Faihan 03 June 2015 (has links)
No description available.
137

Development of Advanced Molecular Tools for Sequence Typing and Epidemiological Investigation of Avian Mycoplasma in Poultry

Ghanem, Mostafa Ghanem Ahmed 07 September 2017 (has links)
No description available.
138

Étude de la prévalence, de la pathogénicité, de la résistance aux antimicrobiens de Salmonella et de l’impact de certains facteurs de risque sur la présence de Salmonella dans les élevages ovins du Québec.

Cenatus, Schlasiva 12 1900 (has links)
Salmonella est un agent pathogène animal et zoonotique d'importance mondiale. Les infections causées par cette bactérie chez les animaux d’élevage peuvent être asymptomatiques ou se traduire par une gastro-entérite ou une maladie invasive. Chez les humains, les maladies d’origines alimentaires associées à Salmonella sont principalement causées par l'ingestion de produits d'origine animale contaminés. Cependant, aucune étude n’a déterminé la prévalence ou caractérisé le profil de virulence et d’antibiorésistance de Salmonella provenant des fermes ovines du Québec, alors que cette province détient le 2ème plus grand cheptel ovin canadien. Ainsi, cette étude visait à estimer la prévalence des fermes ovines positives à Salmonella dans la province du Québec, à identifier les sérotypes circulant dans ces troupeaux, à caractériser le profil de virulence et de résistance aux antimicrobiens de souches de Salmonella isolées dans ces fermes et à évaluer l'influence de certains facteurs de risque (ex. la saisonnalité, la taille des troupeaux et le type de production) sur la prévalence de fermes ovines positives à Salmonella au Québec. Pour cela, 61 fermes ovines du Québec ont été sélectionnées aléatoirement et ont été échantillonnées. Un pool fécal provenant de 10 animaux a été prélevé par ferme. Des milieux sélectifs ont été utilisés pour isoler Salmonella dans chaque échantillon. La confirmation de Salmonella a été faite par des tests biochimiques suivis par la détection du gène invA par PCR et les sous-espèces ont été identifiées par PCR multiplex. Le rapport de prévalence a été calculé pour évaluer l’association entre les facteurs de risque et la présence de Salmonella dans les fermes. Le séquençage du génome complet de 76 isolats a permis d’identifier les sérotypes et de déterminer le profil de virulence et de résistance génotypique de ces isolats. La confirmation de la résistance phénotypique de différentes souches a été effectuée en utilisant la méthode de diffusion en milieu solide (antibiogramme) et la méthode de dilution en milieu liquide. Les résultats indiquent que 83,6% (95% CI 74,3%-92,9%) des troupeaux sont porteurs de Salmonella. Le sérotype Salmonella enterica sous-espèce diarizonae 61 k:1, 5, (7) (Sheep associated Salmonella diarizonae (SASd) a été le seul sérotype identifié dans tous les isolats qui ont été séquencés. Aucun des facteurs de risque évalués n’était associée à la présence de Salmonella. En outre, aucun gène de résistance aux antimicrobiens n’a été identifié à partir de l’analyse des génomes séquencés et toutes les souches ont été révélées comme étant phénotypiquement sensibles aux différents antimicrobiens testés. De plus, des facteurs de virulence, comme les ilots de pathogénicité (SPI-1, SPI-2, SPI-3, SPI-5, SPI-9 et SPI-13) et le plasmide (IncX1), ont été identifiés chez les 84 SASd. Cette étude est la première à rapporter que la prévalence des fermes ovines positives à Salmonella est élevée au Québec (83,6%). Seule la présence du sérotype 61 k:1, 5, (7) a été détectée. Finalement, toutes les souches de Salmonella isolées dans le cadre de cette étude étaient sensibles aux antimicrobiens testés. / Salmonella is a world-known animal and zoonotic pathogen. Infections caused by this bacterium in livestock can be asymptomatic or result in gastroenteritis or an invasive disease. In humans, food-related diseases associated with Salmonella are mainly caused by the ingestion of contaminated products of animal origin. However, no studies have determined the prevalence or characterized the virulence and antimicrobial resistance (AMR) profiles of Salmonella from sheep farms in Quebec, where the province holds the second largest sheep population in Canada. This study aimed to estimate the prevalence of Salmonella-positive sheep farms in the province of Quebec, to identify the serotypes circulating in these flocks, to characterize the virulence and AMR profiles of Salmonella strains isolated from these farms and to assess the influence of some potential risk factors on the prevalence of Salmonella-positive sheep farms in the province of Quebec. For this purpose, 61 sheep farms in Quebec were randomly selected and sampled. A fecal pool including samples from 10 animals was collected per farm. Selective culture media were used to isolate Salmonella in each sample. Salmonella was confirmed by biochemical tests followed by the detection of invA gene by PCR and the subspecies were identified by multiplex PCR. The prevalence ratio was calculated to assess the association between risk factors and the presence of Salmonella in farms. The Whole genome sequencing (WGS) of 76 isolates was used to determine the serotypes, the virulence and the AMR profile of these isolates. The confirmation of the phenotypic AMR of these isolates (n=76) was carried out using the Kirby–Bauer disk diffusion method (antibiogram) or the broth microdilution method. The results indicated that 83.6% (95% CI 74.3%-92.9%) of the flocks are carrier of Salmonella and only the Salmonella enterica subspecies diarizonae serotype 61: k: 1, 5, (7) (sheep associated S. diarizonae, SASd) was identified. None of the tested risk factors was associated with Salmonella positivity at the flock level. In addition, no AMR genes were identified from the WGS data, and all strains were phenotypically sensitive to the various antimicrobials tested. In addition, virulence factors such as pathogenicity islands (SPI-1, SPI-2, SPI-3, SPI-5, SPI-9 and SPI-13) and plasmid (IncX1) have been identified in the sequenced strains. This study was the first to report a high prevalence of Salmonella-positive sheep farms in Quebec (83.6%). Only the presence of serotype 61 k:1, 5, (7) was detected. Interestingly, all Salmonella strains isolated in this study were sensitive to the tested antimicrobials.
139

Characterization of fungicide resistance in grape powdery and downy mildew using field trials, bioassays, genomic, and transcriptomic approaches: quinoxyfen, phosphite, and mandipropamid

Feng, Xuewen 06 February 2018 (has links)
Development of fungicide resistance in fungal and oomycete pathogens is a serious problem in grape production. Quinoxyfen is a fungicide widely used against grape powdery mildew (Erysiphe necator). In 2013, E. necator isolates with reduced quinoxyfen sensitivity (designated as quinoxyfen lab resistance or QLR) were detected in Virginia. Field trials were conducted in 2014, 2015, and 2016 at the affected vineyard to determine to what extent quinoxyfen might still contribute to disease control. Powdery mildew control by quinoxyfen was good, similar to, or only slightly less, than that provided by myclobutanil and boscalid in all three years. The frequency of QLR in vines not treated with quinoxyfen declined only slowly over the three years, from 65% to 46%. Information about the mode of action of quinoxyfen is limited; previous research suggests that quinoxyfen interferes with the signal transduction process. We profiled the transcriptomes of QLR and sensitive isolates in response to quinoxyfen treatment, providing support for this hypothesis. Additional transcriptional targets of quinoxyfen were revealed to be involved in the positive regulation of the MAPK signaling cascade, pathogenesis, and sporulation activity. Grape downy mildew (Plasmopara viticola), another important grape pathogen, is commonly controlled by phosphite fungicides. A field trial and laboratory bioassays were conducted to determine whether P. viticola isolates from vineyards with suspected control failures showed reduced sensitivity against phosphite fungicides. Prophyt applied at 14-day intervals under high disease pressure provided poor downy mildew control in the field. Next-generation sequencing technologies were utilized to identify 391,930 single nucleotide polymorphisms (SNPs) and generated a draft P. viticola genome assembly at ~130 megabase (Mb). Finally, field isolates of P. viticola collected from a Virginia vineyard with suspected mandipropamid control failure were bioassayed. The EC50 values of the isolates were >240 μg.ml-1 for mandipropamid, well above the field rate. The PvCesA3 gene of two resistant isolates was sequenced revealing that these isolates had a GGC-to-AGC substitution at codon 1105, the same mutation that has been found associated with CAA resistance elsewhere. / PHD / Powdery and downy mildew are two diseases of grapes that can cause large yield losses, and are usually controlled by regular fungicide applications. Development of fungicide resistance has been a growing challenge. Quinoxyfen is a protectant fungicide commonly used against powdery mildews. Unusual grape powdery mildew isolates that grew well on quinoxyfen-treated plants in the laboratory (designated as quinoxyfen lab resistance or QLR) were detected in a Virginia vineyard. In 2014, the first year of this study, 65% of powdery mildew isolates from parts of this vineyard that received no further quinoxyfen treatments had the QLR type of resistance, and this declined only slowly to 46% by the third year. Field trials were conducted in 2014, 2015, and 2016 to determine the efficacy of quinoxyfen in the presence of QLR. Powdery mildew control by quinoxyfen on both grape clusters and leaves was similar to, or only slightly less, than that provided by the standard anti-powdery mildew fungicides myclobutanil and boscalid in all three years. In order to gain a better understanding of the mode(s) of action and resistance mechanism(s) of quinoxyfen, gene expression of QLR and sensitive isolates, both in the presence and absence of quinoxyfen, was analyzed by nucleic acid sequencing. This study confirms previous research suggesting that quinoxyfen interferes with the important biological process signal transduction, and revealed additional gene targets of quinoxyfen. The phosphites are a group of fungicides commonly used to control grape downy mildew. Control failures after phosphite application have occasionally been suspected, and downy mildew isolates from vineyards with and without suspected control failures were tested in laboratory bioassays to determine if any level of resistance could be demonstrated. There was a limited range of sensitivity, and none of the isolates showed a notable loss of sensitivity. A field trial was conducted to determine the efficacy of one phosphite fungicide, Prophyt, applied at 14-day intervals under conditions favorable for disease development. Prophyt provided poor downy mildew control, suggesting that it has to be applied more frequently. Next-generation sequencing technologies were utilized to identify genetic markers for clade identification and generated a draft genome assembly of grape downy mildew, which improves the understanding of grape downy mildew genome. Grape downy mildew isolates collected from a vineyard in Virginia where mandipropamid provided poor control of downy mildew were bioassayed. The isolates tolerated mandipropamid rates well above the field rate, showing that they were indeed resistant. The mutation that confers mandipropamid resistance on other continents was found in the PvCesA3 gene of two resistant isolates.
140

Infecções respiratórias por bocavirus humano: aspectos clínicos e moleculares / Respiratory infections by human bocavirus: molecular and clinical features.

Modena, José Luiz Proença 20 May 2009 (has links)
O bocavirus humano (HBoV) é um parvovirus recentemente identificado em associação com a presença de sintomas de infecção do trato respiratório. Esse vírus possui um genoma de aproximadamente 5217 nucleotídeos que contém 3 open reading frames que codificam 4 proteínas (NS1, NP-1, VP-1 e VP-2). HBoV tem sido detectado em amostras respiratórias de diversas partes do mundo, incluindo Austrália, América do Norte, Europa, Ásia e África, o que sugere uma distribuição global desse vírus. Entretanto, nenhum estudo longitudinal de HBoV em amostras respiratórias foi realizado na América Latina. Dessa forma, nós realizamos um estudo prospectivo de HBoV em lavados nasofaríngeos (LFNs) coletados de pacientes com sintomas de infecção do trato respiratório (IRA) atendidos em um hospital universitário de Ribeirão Preto, SP e em um hospital universitário de Salvador, BA no período entre 2005 a 2007. 1288 LFNs de 1217 pacientes foram encaminhados ao laboratório de virologia e foram testados por PCR para HBoV. Desses pacientes, 962 eram menores de 5 anos e 177 eram maiores de 5 anos. Além disso, também foram analisados 50 LFNs de crianças menores de 5 anos que não tinham sintomas respiratórios. Todas as amostras positivas para HBoV foram testadas para todos os outros vírus respiratórios, incluindo o vírus sincicial respiratório (HRSV), rinovirus humano (HRV), influenza humano (HFLU), metapneumovirus humano (HMPV), parainfluenza humano (HPIV), coronavirus humano (HCoV) e adenovirus humano (HAdV). A carga viral de HBoV foi determinada por PCR em tempo real em todas as amostras positivas e o genoma completo de 19 amostras de HBoV foi seqüenciado. Com intuito, de fazer um levantamento sorológico e determinar sítios replicativos de HBoV, nós ainda clonamos e expressamos em S. cerevisae (Y258) o gene de VP2, que codifica uma das proteínas do capsídeo viral. A prevalência desse vírus foi de 4,8% em crianças menores de cinco anos e de 1% em pacientes maiores de cinco anos. HBoV não foi detectado em crianças sem sintomas. Dos 259 pacientes analisados em 2005, 25 (10%) foram positivos para HBoV. Esse vírus circulou mais frequentemente em abril, mês de maior incidência do HRSV. Em 2006, HBoV foi detectado em apenas 10 LFNs de 334 (3%) amostras testadas, sem qualquer pico de freqüência. Em 2007 HBoV foi detectado em 13 de 552 (2%) amostras, com uma freqüência de detecção um pouco maior em junho e julho. Os sintomas mais comumente observados foram rinorréia, tosse, febre e chiado, que foram observados geralmente em mais de 50% dos casos positivos para HBoV. Não houve uma diferença significativa na prevalência desses sintomas entre as crianças positivas e negativas para HBoV. Entretanto, foi observada uma maior freqüência de diarréia entre as crianças com esse vírus. Nesse estudo também foi documentado uma alta freqüência de co-infecções virais entre os pacientes com HBoV. Os vírus mais frequentemente associados com o bocavirus humano foram: HRSV, HRV e HAdV. Além disso, foi detectado uma maior carga viral media e uma maior freqüência de diarréia nos 15 pacientes com infecção exclusiva por HBoV do que nos pacientes com co-infecção. Esses resultados mostraram que HBoV pode alcançar títulos enormes (tão grandes como1014/mL) em LFNs de pacientes com sintomas respiratórios e que isso é associado a de diarréia. O seqüenciamento do genoma inteiro de HBoV realizado nesse estudo indica que a divergência genômica entre as amostras desse vírus é muito pequena. Como conclusão, nós demonstramos que HBoV circula e é detectado em associação com sintomas de infecção respiratória e diarréia no Brasil. Novos estudos, com um longo acompanhamento em diferentes populações serão necessários para determinar a sazonalidade e o real impacto clínico de HBoV em nosso país. / Human bocavirus (HBoV) is a parvovirus recently identified in association with respiratory tract infections. HBoV 5217 nt genome contains 3 open reading frames encoding four proteins (NS1, NP-1, VP-1 and VP-2). HBoV has been reported in respiratory samples from children in several parts of the world (including Australia, North America, Europe, Asia, and Africa), suggesting that the virus circulates worldwide. However, no longitudinal studies of HBoV in respiratory samples have been reported in Latin America. We report a prospective study of HBoV in nasopharyngeal aspirates (NPAs) collected from patients seen for acute respiratory tract infections (ARI) at the University of Sao Paulo Hospital in Ribeirao Preto, southeast Brazil and at the University Hospital in Salvador, Brazil. 1288 NPAs from 1217 patients was submitted to the virology lab for respiratory virus detection from 2005 to 2007 and were screened for HBoV by polymerase chain reaction (PCR), whom 962 were under 5 years of age and 177 were older than 5 years. In addition, NPAs from 50 children under 12 years without IRA was also tested to HBoV for PCR. All samples positive of HBoV was tested for others respiratory virus, including the human respiratory syncitial virus (HRSV), human rhinovirus (HRV), human influenza (HFLU), human metapneumovirus (HMPV), human parainfluenza virus (HPIV), human coronavirus (HCoV) and human adenovirus (HAdV). These samples had their HBoV viral load determined by real time PCR and the viral entire genome of nineteen HBoV sample was sequenced. We also cloned and expressed in S. cerevisae (Y258) the gene of VP2, one protein of viral capside. The prevalence of this virus was of 4,8% in children under 5 years and 1% in adults, both with IRA. HBoV was not found on the patients without symptoms. In 2005, of the 259 patients tested, 25 (10%) were positive for HBoV. Interestingly, the virus circulated more frequently in April, the month of peak activity of respiratory HRSV. In 2006 HBoV was detected in only 10 NPAs out of 334 samples (3%) tested, without any notable peak of frequency. In 2007 HBoV was detected in 13 out of 552 (2%) tested samples with little higher frequency of detection in June an July. Rhinorrhea, cough, and wheezing were observed in more than 50% of the HBoV-positive children, and no obvious respiratory clinical differences were noted between HBoV-positive and negative children. However, was noted a higher frequency of diarrhea on HBoV-positive patients. In this study was also observed a larger frequency (71%) of viral coinfections between the HBoV-positive patients. The respiratory viruses more frequently associated with human bocavirus were: HRSV, HRV and HAdV. Interestingly, on the 15 HBoV-alone patients was observed a higher viral load and a higher prevalence of diarrhea than HBoV-coinfection patients. These results showed that this virus can reach enormous titles (like 1014) in NPAs from patients with respiratory infection symptoms and this is associated with diahhrea. The entire genome sequencing of HBoV of our study indicates that the genetic divergence between the HBoV lineages is small. In conclusion, we demonstrated that HBoV circulates and is detected in association with respiratory symptoms and diarrhea in Brazil. Long term surveillance will be needed to determine whether or not an HBoV season occurs and what is the real clinical impact of this virus in our country.

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