25 research outputs found
Detection, quantification and genetic variability of Mycoplasma hyopneumoniae from apparently healthy and pneumonic swine
Mycoplasma hyopneumoniae is the causative agent of the Porcine Enzootic Pneumonia. However, this mycoplasma can be detected in healthy and symptomatic pigs, that difficults the conclusion for the etiology of this disease. In the present study we aimed to detect, quantify and do molecular analyses of M. hyopneumoniae strains in respiratory clinical samples recovered from healthy pigs and from those with pneumonia or other respiratory symptoms. The analytical sensitivity and specificity of PCR assays directed to Mollicutes detection and porcine mycoplasmas identification in clinical samples were evaluated. The identification of M. hyopneumoniae in the samples was performed using different molecular approaches, Multiplex PCR, Real Time PCR and Multilocus Variable-Number Tandem-Repeat amplification. Molecular characterization of the strains was achieved by determining and comparing the VNTR copy number directly in the samples. The highest number of samples positive to M. hyopneumoniae was identified by the multilocus VNTR amplification assay using labeled primers, followed by capillary electrophoresis. The highest concentration of M. hyopneumoniae was detected in pneumonic lungs (2, 3 * 108 genome copies /mL). The VNTR copy number analysis demonstrated that despite the high genetic variability of the M. hyopneumoniae strains, predominant strains in the swine farms could be identified by means of the VNTR copy number analysis of P97R1 and P146R3. (English)Molecular differences among Mycoplasma hyopneumoniae strains present in pneumonic lungs of swine have been largely studied. However, no comparative studies concerning the strains present in apparently healthy pigs have been carried out. This study aimed to detect, quantify and perform molecular analysis of M. hyopneumoniae strains in pig lungs with and without pneumonic lesions. The detection of M. hyopneumoniae was performed using multiplex PCR (YAMAGUTI, 2008), real-time PCR (STRAIT et al., 2008) and multiple VNTR amplification (VRANCKX et al., 2011). Molecular characterization of the strains was achieved by analysis of the VNTR copy number in P97R1, P146R3, H2R1 and H4. M. hyopneumoniae was detected in samples from healthy and pneumonic pigs and the amount of M. hyopneumoniae positive samples detected varied with the type of assay. The greater number of positive samples was identified by the multiple VNTR amplification combined with capillary electrophoresis. Using real-time PCR, 4.9*104 M. hyopneumoniae genome copies/mL was detected in apparently healthy lungs. A mean quantity of 3.9*106 M. hyopneumoniae genome copies/mL was detected in pneumonic lungs. The analysis of VNTR copy number demonstrated a high genetic variability of the M. hyopneumoniae strains present in apparently healthy and pneumonic lungs. Strains having 3 VNTR copy number in P97R1, were detected only in pneumonic lungs and strains having 40 and 43 VNTR copy number in P146R3 were detected only in apparently healthy lungs. Despite the genetic variability of M. hyopneumoniae, predominant strains in the swine farms could be identified.As diferenças moleculares entre as estirpes de Mycoplasma hyopneumoniae presentes em pulmões de suĂnos com pneumonia tem sido estudadas. PorĂ©m, estudos comparativos relativos as estirpes presentes nos suĂnos aparentemente saudáveis nĂŁo foram levados a cabo. O objetivo do estudo foi a detecção, quantificação e analise molecular de M. hyopneumoniae nos pulmões suĂnos com e sem lesões pneumĂ´nicas. Para a detecção de M. hyopneumoniae usaramse o PCR Multiplo (YAMAGUTI, 2008), o PCR a Tempo Real (STRAIT et al., 2008) e a amplificação de mĂşltiplo VNTR (VRANCKX et al., 2011). A caracterização molecular das estirpes foi realizada mediante a análise do nĂşmero de copias de VNTR em P97R1, P146R3, H2R1 e H4. O M. hyopneumoniae foi detectado em amostras de suĂnos saudáveis e pneumĂ´nicos e a quantidade de M. hyopneumoniae nas amostras positivas variou com o tipo de ensaio. O maior nĂşmero de amostras positivas foi identificado pela amplificação de mĂşltiplas VNTR combinado com a eletroforese de capilares. Usando o PCR a Tempo Real, 4.9*104 copias de genoma/mL de M. hyopneumoniae foram detectadas em pulmões aparentemente saudáveis. Uma quantidade mĂ©dia de 3.9*106 copias de genoma/mL de M. hyopneumoniae foi detectada em pulmões pneumĂ´nicos. A análise do nĂşmero de copias de VNTR demonstrou uma elevada variabilidade
Caracterização do vĂrus da raiva isolado de uma colĂ´nia de morcegos Eptesicus furinalis, do Brasil
Some bat species have adapted to the expanding human population by acquiring the ability to roost in urban buildings, increasing the exposure risk for people and domestic animals, and consequently, the likelihood of transmitting rabies. Three dead bats were found in the yard of a house in an urban area of JundiaĂ city in the state of SĂŁo Paulo in southeast Brazil. Two of the three bats tested positive for rabies, using Fluorescent Antibody and Mouse Inoculation techniques. A large colony of Eptesicus furinalis was found in the house's attic, and of the 119 bats captured, four more tested positive for rabies. The objectives of this study were to report the rabies diagnosis, characterize the isolated virus antigenically and genetically, and study the epidemiology of the colony.Algumas espĂ©cies de morcegos tĂŞm se adaptado ao uso de abrigos em construções urbanas, aumentando a possibilidade de contato desses morcegos com pessoas e animais domĂ©sticos e conseqĂĽentemente, o potencial risco de transmissĂŁo de raiva. TrĂŞs morcegos foram encontrados no jardim de uma casa na área urbana da cidade de JundiaĂ, Estado de SĂŁo Paulo, Sudeste do Brasil, dois deles foram positivos para raiva pelas tĂ©cnicas de imunofluorescĂŞncia e inoculação em camundongos. Uma grande colĂ´nia de E. furinalis foi identificada, vivendo no sĂłtĂŁo da casa e 119 morcegos foram encaminhados para diagnĂłstico de raiva, com mais quatro morcegos positivos. O objetivo desse estudo Ă© apresentar a caracterização genĂ©tica e antigĂŞnica do vĂrus da raiva isolado desses morcegos e o estudo epidemiolĂłgico da colĂ´nia
Detection, quantification and genetic variability of Mycoplasma hyopneumoniae from apparently healthy and pneumonic swine
Prevalence of bat viruses associated with land-use change in the Atlantic Forest, Brazil
Introduction: Bats are critical to maintaining healthy ecosystems and many species are threatened primarily due to global habitat loss. Bats are also important hosts of a range of viruses, several of which have had significant impacts on global public health. The emergence of these viruses has been associated with land-use change and decreased host species richness. Yet, few studies have assessed how bat communities and the viruses they host alter with land-use change, particularly in highly biodiverse sites.
Methods: In this study, we investigate the effects of deforestation on bat host species richness and diversity, and viral prevalence and richness across five forested sites and three nearby deforested sites in the interior Atlantic Forest of southern Brazil. Nested-PCR and qPCR were used to amplify and detect viral genetic sequence from six viral families (corona-, adeno-, herpes-, hanta-, paramyxo-, and astro-viridae) in 944 blood, saliva and rectal samples collected from 335 bats.
Results: We found that deforested sites had a less diverse bat community than forested sites, but higher viral prevalence and richness after controlling for confounding factors. Viral detection was more likely in juvenile males located in deforested sites. Interestingly, we also found a significant effect of host bat species on viral prevalence indicating that viral taxa were detected more frequently in some species than others. In particular, viruses from the Coronaviridae family were detected more frequently in generalist species compared to specialist species.
Discussion: Our findings suggest that deforestation may drive changes in the ecosystem which reduce bat host diversity while increasing the abundance of generalist species which host a wider range of viruses
Molecular characterization of rabies virus isolated from non-haematophagous bats in Brazil
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
Genetic study from Rabies vĂrus variant maintained by hematophagous bats Desmodus rotundus population.
Dados da Organização Mundial da SaĂşde (OMS) mostram que a raiva Ă© um problema de saĂşde pĂşblica podendo acarretar sĂ©rios prejuĂzos ambientais e econĂ´micos, a despeito da existĂŞncia de vacinas eficazes de uso humano e veterinário. Segundo seu Ăşltimo informe, estima-se que no mundo em torno de 55.000 pessoas por ano morrem de raiva. O cĂŁo permanece como principal transmissor da raiva para o homem e tambĂ©m como principal vĂtima da doença. Nos paĂses que conseguiram controlar a raiva em animais domĂ©sticos, o vĂrus se mantĂ©m circulante na natureza por meio dos animais silvestres, sendo os morcegos apontados como a segunda espĂ©cie transmissora da raiva a humanos. Os Lyssavirus tĂŞm sido detectados em morcegos, em diversos continentes, sendo identificados como transmissor em dez das onze espĂ©cies de Lyssavirus. FĂłsseis de morcego mostram sua presença há 50 milhões de anos. Mas somente em 1911, Carini relacionou pela primeira vez a raiva aos morcegos, levantando a hipĂłtese destes serem os transmissores da doença a outros animais. Há registros de que o vĂrus da raiva foi isolado em pelo menos 41 das 167 espĂ©cies de morcegos brasileiras, sendo que a maioria dessas espĂ©cies está relacionada a atividades humanas com a presença destes animais prĂłximos ao local de trabalho e moradia das pessoas. Os morcegos hematĂłfagos Desmodus rotundus sĂŁo encontrados do norte do MĂ©xico atĂ© a costa norte do Chile, regiĂŁo central da Argentina e costa do Uruguai e com exceção do Chile. Esta espĂ©cie de morcego tem sido apontada como reservatĂłrio natural do vĂrus da raiva nesta regiĂŁo. Alguns pesquisadores observaram que a raiva em morcegos nĂŁo hematĂłfagos precede a raiva bovina e em animais de estimação, sugerindo que os morcegos nĂŁo hematĂłfagos podem ser o elo entre a raiva silvestre e a raiva urbana e o fato de se detectar a variante mantida por morcegos hematĂłfagos Desmodus rotundus em cĂŁes e gatos mostra que o papel deste morcego no ciclo da raiva nĂŁo está limitado Ă raiva silvestre. As caracterĂsticas dos Lyssavirus adaptados a morcegos tĂŞm mostrado diferenças quando comparadas Ă raiva relacionada aos carnĂvoros, confirmando a necessidade do desenvolvimento de metodologias que permitam estudos complementares mais precisos a respeito da biologia e epidemiologia da raiva em quirĂłpteros. A escassez de dados na literatura, atĂ© o momento, a respeito do genoma completo da variante do vĂrus da raiva mantida por populações de morcegos hematĂłfagos Desmodus rotundus, deixa uma lacuna no entendimento da epidemiologia molecular deste vĂrus. A importância epidemiolĂłgica desta espĂ©cie na transmissĂŁo da raiva Ă© inquestionável. Neste estudo foi sequenciado e analisado, o genoma da variante do vĂrus da raiva mantido por populações de morcego hematĂłfago Desmodus rotundus isolado de um morcego hematĂłfago Desmodus rotundus. A amostra, procedente de área endĂŞmica no Estado de SĂŁo Paulo, foi filogeneticamente comparada com o genoma da amostra padrĂŁo para a espĂ©cie viral 1 - Rabies virus e outras amostras pertencentes ao ciclo aĂ©reo ou terrestre de transmissĂŁo, disponĂveis no GenBank, identificando possĂveis padrões de diferenciação, prĂłprios do ciclo aĂ©reo, e em alguns casos relacionados somente Ă variante estudada.Data from the World Health Organization (WHO) show that rabies is a public health problem which can cause serious environmental and economic damage, despite the existence of effective vaccines for human and veterinary use. According to WHO latest report, estimated that worldwide around 55,000 people per year died of rabies. The dog remains the main transmitter of rabies to humans as well as the main victim of the disease. In countries that were successful in controlling rabies in domestic animals, the virus is still circulating in nature by wild animals and the bats are seen as the second species transmitting rabies to humans. The Lyssavirus have been detected in bats in several continents and is identified as a transmitter in ten of eleven species of Lyssavirus. Bat fossils show their presence for 50 million years. But only in 1911, in the first time Carini related to rabies at bats, raising the possibility of these being the transmitters of the disease to other animals. Reports show that the Rabies virus was isolated in at least 41 of the 167 species of bats in Brazil, with the majority of these species is related to human activities with the animals living near the local job and houses of people. The vampire bat Desmodus rotundus is found from northern Mexico to northern Chile coast, central coast of Argentina and Uruguay and with the exception of Chile. This bat species has been identified as a natural reservoir of the Rabies virus in this region. Some researchers observed that rabies into non-hematophagous bats precedes the bovine rabies and in pets, suggesting that the non-hematophagous bats may be the link between wildlife rabies and urban rabies and the fact that detect the variant maintained by vampire bats Desmodus rotundus in dogs and cats shows that the role of bat rabies in the cycle is not limited to wildlife rabies. The characteristics of Lyssavirus bat adapted have been shown differences when compared to rabies related to the carnivores, confirming the need to develop methods that enable more accurate follow-up studies about the biology and epidemiology of rabies in bats. The paucity of data in the literature to date about the complete genome of the Rabies virus variant maintained by populations of vampire bats Desmodus rotundus leaves a gap in understanding the molecular epidemiology of this virus and the epidemiological importance of this species in the transmission of Rabies virus is unquestionable. In this study we sequenced and analyzed the genome of the Rabies virus variant maintained by populations of bat Desmodus rotundus isolated from a bat Desmodus rotundus. The sample, coming from an endemic area in SĂŁo Paulo, was phylogenetically compared with the genome of the standard sample for spcies 1 - Rabies virus and other samples belonging to the Terrestrial and Aerial cycles of transmission, available in GenBank, to identify possible patterns of differentiating themselves Aerial cycle and in some cases linked only to variant studied